publicdata/nist-gov
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions
nist-gov/www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies
Scott Williams 4063bef310 Initital commit.
2025-03-05 18:59:57 +00:00

1644 lines
120 KiB
Text
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

<!DOCTYPE html>
<html lang="en" dir="ltr" prefix="content: http://purl.org/rss/1.0/modules/content/ dc: http://purl.org/dc/terms/ foaf: http://xmlns.com/foaf/0.1/ og: http://ogp.me/ns# rdfs: http://www.w3.org/2000/01/rdf-schema# schema: http://schema.org/ sioc: http://rdfs.org/sioc/ns# sioct: http://rdfs.org/sioc/types# skos: http://www.w3.org/2004/02/skos/core# xsd: http://www.w3.org/2001/XMLSchema# ">
<head>
<meta charset="utf-8" /><script type="text/javascript">(window.NREUM||(NREUM={})).init={ajax:{deny_list:["bam.nr-data.net"]}};(window.NREUM||(NREUM={})).loader_config={licenseKey:"37b7ccb661",applicationID:"1089704227"};;/*! For license information please see nr-loader-rum-1.283.2.min.js.LICENSE.txt */
(()=>{var e,t,r={122:(e,t,r)=>{"use strict";r.d(t,{a:()=>i});var n=r(944);function i(e,t){try{if(!e||"object"!=typeof e)return(0,n.R)(3);if(!t||"object"!=typeof t)return(0,n.R)(4);const r=Object.create(Object.getPrototypeOf(t),Object.getOwnPropertyDescriptors(t)),o=0===Object.keys(r).length?e:r;for(let a in o)if(void 0!==e[a])try{if(null===e[a]){r[a]=null;continue}Array.isArray(e[a])&&Array.isArray(t[a])?r[a]=Array.from(new Set([...e[a],...t[a]])):"object"==typeof e[a]&&"object"==typeof t[a]?r[a]=i(e[a],t[a]):r[a]=e[a]}catch(e){(0,n.R)(1,e)}return r}catch(e){(0,n.R)(2,e)}}},555:(e,t,r)=>{"use strict";r.d(t,{Vp:()=>c,fn:()=>s,x1:()=>u});var n=r(384),i=r(122);const o={beacon:n.NT.beacon,errorBeacon:n.NT.errorBeacon,licenseKey:void 0,applicationID:void 0,sa:void 0,queueTime:void 0,applicationTime:void 0,ttGuid:void 0,user:void 0,account:void 0,product:void 0,extra:void 0,jsAttributes:{},userAttributes:void 0,atts:void 0,transactionName:void 0,tNamePlain:void 0},a={};function s(e){try{const t=c(e);return!!t.licenseKey&&!!t.errorBeacon&&!!t.applicationID}catch(e){return!1}}function c(e){if(!e)throw new Error("All info objects require an agent identifier!");if(!a[e])throw new Error("Info for ".concat(e," was never set"));return a[e]}function u(e,t){if(!e)throw new Error("All info objects require an agent identifier!");a[e]=(0,i.a)(t,o);const r=(0,n.nY)(e);r&&(r.info=a[e])}},217:(e,t,r)=>{"use strict";r.d(t,{D0:()=>m,gD:()=>v,xN:()=>h});r(860).K7.genericEvents;const n="experimental.marks",i="experimental.measures",o="experimental.resources",a=e=>{if(!e||"string"!=typeof e)return!1;try{document.createDocumentFragment().querySelector(e)}catch{return!1}return!0};var s=r(614),c=r(944),u=r(384),l=r(122);const d="[data-nr-mask]",f=()=>{const e={feature_flags:[],experimental:{marks:!1,measures:!1,resources:!1},mask_selector:"*",block_selector:"[data-nr-block]",mask_input_options:{color:!1,date:!1,"datetime-local":!1,email:!1,month:!1,number:!1,range:!1,search:!1,tel:!1,text:!1,time:!1,url:!1,week:!1,textarea:!1,select:!1,password:!0}};return{ajax:{deny_list:void 0,block_internal:!0,enabled:!0,autoStart:!0},distributed_tracing:{enabled:void 0,exclude_newrelic_header:void 0,cors_use_newrelic_header:void 0,cors_use_tracecontext_headers:void 0,allowed_origins:void 0},get feature_flags(){return e.feature_flags},set feature_flags(t){e.feature_flags=t},generic_events:{enabled:!0,autoStart:!0},harvest:{interval:30},jserrors:{enabled:!0,autoStart:!0},logging:{enabled:!0,autoStart:!0},metrics:{enabled:!0,autoStart:!0},obfuscate:void 0,page_action:{enabled:!0},page_view_event:{enabled:!0,autoStart:!0},page_view_timing:{enabled:!0,autoStart:!0},performance:{get capture_marks(){return e.feature_flags.includes(n)||e.experimental.marks},set capture_marks(t){e.experimental.marks=t},get capture_measures(){return e.feature_flags.includes(i)||e.experimental.measures},set capture_measures(t){e.experimental.measures=t},capture_detail:!0,resources:{get enabled(){return e.feature_flags.includes(o)||e.experimental.resources},set enabled(t){e.experimental.resources=t},asset_types:[],first_party_domains:[],ignore_newrelic:!0}},privacy:{cookies_enabled:!0},proxy:{assets:void 0,beacon:void 0},session:{expiresMs:s.wk,inactiveMs:s.BB},session_replay:{autoStart:!0,enabled:!1,preload:!1,sampling_rate:10,error_sampling_rate:100,collect_fonts:!1,inline_images:!1,fix_stylesheets:!0,mask_all_inputs:!0,get mask_text_selector(){return e.mask_selector},set mask_text_selector(t){a(t)?e.mask_selector="".concat(t,",").concat(d):""===t||null===t?e.mask_selector=d:(0,c.R)(5,t)},get block_class(){return"nr-block"},get ignore_class(){return"nr-ignore"},get mask_text_class(){return"nr-mask"},get block_selector(){return e.block_selector},set block_selector(t){a(t)?e.block_selector+=",".concat(t):""!==t&&(0,c.R)(6,t)},get mask_input_options(){return e.mask_input_options},set mask_input_options(t){t&&"object"==typeof t?e.mask_input_options={...t,password:!0}:(0,c.R)(7,t)}},session_trace:{enabled:!0,autoStart:!0},soft_navigations:{enabled:!0,autoStart:!0},spa:{enabled:!0,autoStart:!0},ssl:void 0,user_actions:{enabled:!0,elementAttributes:["id","className","tagName","type"]}}},g={},p="All configuration objects require an agent identifier!";function m(e){if(!e)throw new Error(p);if(!g[e])throw new Error("Configuration for ".concat(e," was never set"));return g[e]}function h(e,t){if(!e)throw new Error(p);g[e]=(0,l.a)(t,f());const r=(0,u.nY)(e);r&&(r.init=g[e])}function v(e,t){if(!e)throw new Error(p);var r=m(e);if(r){for(var n=t.split("."),i=0;i<n.length-1;i++)if("object"!=typeof(r=r[n[i]]))return;r=r[n[n.length-1]]}return r}},371:(e,t,r)=>{"use strict";r.d(t,{V:()=>f,f:()=>d});var n=r(122),i=r(384),o=r(154),a=r(324);let s=0;const c={buildEnv:a.F3,distMethod:a.Xs,version:a.xv,originTime:o.WN},u={customTransaction:void 0,disabled:!1,isolatedBacklog:!1,loaderType:void 0,maxBytes:3e4,onerror:void 0,ptid:void 0,releaseIds:{},appMetadata:{},session:void 0,denyList:void 0,timeKeeper:void 0,obfuscator:void 0,harvester:void 0},l={};function d(e){if(!e)throw new Error("All runtime objects require an agent identifier!");if(!l[e])throw new Error("Runtime for ".concat(e," was never set"));return l[e]}function f(e,t){if(!e)throw new Error("All runtime objects require an agent identifier!");l[e]={...(0,n.a)(t,u),...c},Object.hasOwnProperty.call(l[e],"harvestCount")||Object.defineProperty(l[e],"harvestCount",{get:()=>++s});const r=(0,i.nY)(e);r&&(r.runtime=l[e])}},324:(e,t,r)=>{"use strict";r.d(t,{F3:()=>i,Xs:()=>o,xv:()=>n});const n="1.283.2",i="PROD",o="CDN"},154:(e,t,r)=>{"use strict";r.d(t,{OF:()=>c,RI:()=>i,WN:()=>l,bv:()=>o,gm:()=>a,mw:()=>s,sb:()=>u});var n=r(863);const i="undefined"!=typeof window&&!!window.document,o="undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self.navigator instanceof WorkerNavigator||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis.navigator instanceof WorkerNavigator),a=i?window:"undefined"!=typeof WorkerGlobalScope&&("undefined"!=typeof self&&self instanceof WorkerGlobalScope&&self||"undefined"!=typeof globalThis&&globalThis instanceof WorkerGlobalScope&&globalThis),s=Boolean("hidden"===a?.document?.visibilityState),c=/iPad|iPhone|iPod/.test(a.navigator?.userAgent),u=c&&"undefined"==typeof SharedWorker,l=((()=>{const e=a.navigator?.userAgent?.match(/Firefox[/\s](\d+\.\d+)/);Array.isArray(e)&&e.length>=2&&e[1]})(),Date.now()-(0,n.t)())},687:(e,t,r)=>{"use strict";r.d(t,{Ak:()=>c,Ze:()=>d,x3:()=>u});var n=r(836),i=r(606),o=r(860),a=r(646);const s={};function c(e,t){const r={staged:!1,priority:o.P3[t]||0};l(e),s[e].get(t)||s[e].set(t,r)}function u(e,t){e&&s[e]&&(s[e].get(t)&&s[e].delete(t),g(e,t,!1),s[e].size&&f(e))}function l(e){if(!e)throw new Error("agentIdentifier required");s[e]||(s[e]=new Map)}function d(e="",t="feature",r=!1){if(l(e),!e||!s[e].get(t)||r)return g(e,t);s[e].get(t).staged=!0,f(e)}function f(e){const t=Array.from(s[e]);t.every((([e,t])=>t.staged))&&(t.sort(((e,t)=>e[1].priority-t[1].priority)),t.forEach((([t])=>{s[e].delete(t),g(e,t)})))}function g(e,t,r=!0){const o=e?n.ee.get(e):n.ee,s=i.i.handlers;if(!o.aborted&&o.backlog&&s){if(r){const e=o.backlog[t],r=s[t];if(r){for(let t=0;e&&t<e.length;++t)p(e[t],r);Object.entries(r).forEach((([e,t])=>{Object.values(t||{}).forEach((t=>{t[0]?.on&&t[0]?.context()instanceof a.y&&t[0].on(e,t[1])}))}))}}o.isolatedBacklog||delete s[t],o.backlog[t]=null,o.emit("drain-"+t,[])}}function p(e,t){var r=e[1];Object.values(t[r]||{}).forEach((t=>{var r=e[0];if(t[0]===r){var n=t[1],i=e[3],o=e[2];n.apply(i,o)}}))}},836:(e,t,r)=>{"use strict";r.d(t,{P:()=>c,ee:()=>u});var n=r(384),i=r(990),o=r(371),a=r(646),s=r(607);const c="nr@context:".concat(s.W),u=function e(t,r){var n={},s={},l={},d=!1;try{d=16===r.length&&(0,o.f)(r).isolatedBacklog}catch(e){}var f={on:p,addEventListener:p,removeEventListener:function(e,t){var r=n[e];if(!r)return;for(var i=0;i<r.length;i++)r[i]===t&&r.splice(i,1)},emit:function(e,r,n,i,o){!1!==o&&(o=!0);if(u.aborted&&!i)return;t&&o&&t.emit(e,r,n);for(var a=g(n),c=m(e),l=c.length,d=0;d<l;d++)c[d].apply(a,r);var p=v()[s[e]];p&&p.push([f,e,r,a]);return a},get:h,listeners:m,context:g,buffer:function(e,t){const r=v();if(t=t||"feature",f.aborted)return;Object.entries(e||{}).forEach((([e,n])=>{s[n]=t,t in r||(r[t]=[])}))},abort:function(){f._aborted=!0,Object.keys(f.backlog).forEach((e=>{delete f.backlog[e]}))},isBuffering:function(e){return!!v()[s[e]]},debugId:r,backlog:d?{}:t&&"object"==typeof t.backlog?t.backlog:{},isolatedBacklog:d};return Object.defineProperty(f,"aborted",{get:()=>{let e=f._aborted||!1;return e||(t&&(e=t.aborted),e)}}),f;function g(e){return e&&e instanceof a.y?e:e?(0,i.I)(e,c,(()=>new a.y(c))):new a.y(c)}function p(e,t){n[e]=m(e).concat(t)}function m(e){return n[e]||[]}function h(t){return l[t]=l[t]||e(f,t)}function v(){return f.backlog}}(void 0,"globalEE"),l=(0,n.Zm)();l.ee||(l.ee=u)},646:(e,t,r)=>{"use strict";r.d(t,{y:()=>n});class n{constructor(e){this.contextId=e}}},908:(e,t,r)=>{"use strict";r.d(t,{d:()=>n,p:()=>i});var n=r(836).ee.get("handle");function i(e,t,r,i,o){o?(o.buffer([e],i),o.emit(e,t,r)):(n.buffer([e],i),n.emit(e,t,r))}},606:(e,t,r)=>{"use strict";r.d(t,{i:()=>o});var n=r(908);o.on=a;var i=o.handlers={};function o(e,t,r,o){a(o||n.d,i,e,t,r)}function a(e,t,r,i,o){o||(o="feature"),e||(e=n.d);var a=t[o]=t[o]||{};(a[r]=a[r]||[]).push([e,i])}},878:(e,t,r)=>{"use strict";function n(e,t){return{capture:e,passive:!1,signal:t}}function i(e,t,r=!1,i){window.addEventListener(e,t,n(r,i))}function o(e,t,r=!1,i){document.addEventListener(e,t,n(r,i))}r.d(t,{DD:()=>o,jT:()=>n,sp:()=>i})},607:(e,t,r)=>{"use strict";r.d(t,{W:()=>n});const n=(0,r(566).bz)()},566:(e,t,r)=>{"use strict";r.d(t,{LA:()=>s,bz:()=>a});var n=r(154);const i="xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx";function o(e,t){return e?15&e[t]:16*Math.random()|0}function a(){const e=n.gm?.crypto||n.gm?.msCrypto;let t,r=0;return e&&e.getRandomValues&&(t=e.getRandomValues(new Uint8Array(30))),i.split("").map((e=>"x"===e?o(t,r++).toString(16):"y"===e?(3&o()|8).toString(16):e)).join("")}function s(e){const t=n.gm?.crypto||n.gm?.msCrypto;let r,i=0;t&&t.getRandomValues&&(r=t.getRandomValues(new Uint8Array(e)));const a=[];for(var s=0;s<e;s++)a.push(o(r,i++).toString(16));return a.join("")}},614:(e,t,r)=>{"use strict";r.d(t,{BB:()=>a,H3:()=>n,g:()=>u,iL:()=>c,tS:()=>s,uh:()=>i,wk:()=>o});const n="NRBA",i="SESSION",o=144e5,a=18e5,s={STARTED:"session-started",PAUSE:"session-pause",RESET:"session-reset",RESUME:"session-resume",UPDATE:"session-update"},c={SAME_TAB:"same-tab",CROSS_TAB:"cross-tab"},u={OFF:0,FULL:1,ERROR:2}},863:(e,t,r)=>{"use strict";function n(){return Math.floor(performance.now())}r.d(t,{t:()=>n})},944:(e,t,r)=>{"use strict";function n(e,t){"function"==typeof console.debug&&console.debug("New Relic Warning: https://github.com/newrelic/newrelic-browser-agent/blob/main/docs/warning-codes.md#".concat(e),t)}r.d(t,{R:()=>n})},284:(e,t,r)=>{"use strict";r.d(t,{t:()=>c,B:()=>s});var n=r(836),i=r(154);const o="newrelic";const a=new Set,s={};function c(e,t){const r=n.ee.get(t);s[t]??={},e&&"object"==typeof e&&(a.has(t)||(r.emit("rumresp",[e]),s[t]=e,a.add(t),function(e={}){try{i.gm.dispatchEvent(new CustomEvent(o,{detail:e}))}catch(e){}}({loaded:!0})))}},990:(e,t,r)=>{"use strict";r.d(t,{I:()=>i});var n=Object.prototype.hasOwnProperty;function i(e,t,r){if(n.call(e,t))return e[t];var i=r();if(Object.defineProperty&&Object.keys)try{return Object.defineProperty(e,t,{value:i,writable:!0,enumerable:!1}),i}catch(e){}return e[t]=i,i}},389:(e,t,r)=>{"use strict";function n(e,t=500,r={}){const n=r?.leading||!1;let i;return(...r)=>{n&&void 0===i&&(e.apply(this,r),i=setTimeout((()=>{i=clearTimeout(i)}),t)),n||(clearTimeout(i),i=setTimeout((()=>{e.apply(this,r)}),t))}}function i(e){let t=!1;return(...r)=>{t||(t=!0,e.apply(this,r))}}r.d(t,{J:()=>i,s:()=>n})},289:(e,t,r)=>{"use strict";r.d(t,{GG:()=>o,sB:()=>a});var n=r(878);function i(){return"undefined"==typeof document||"complete"===document.readyState}function o(e,t){if(i())return e();(0,n.sp)("load",e,t)}function a(e){if(i())return e();(0,n.DD)("DOMContentLoaded",e)}},384:(e,t,r)=>{"use strict";r.d(t,{NT:()=>o,US:()=>l,Zm:()=>a,bQ:()=>c,dV:()=>s,nY:()=>u,pV:()=>d});var n=r(154),i=r(863);const o={beacon:"bam.nr-data.net",errorBeacon:"bam.nr-data.net"};function a(){return n.gm.NREUM||(n.gm.NREUM={}),void 0===n.gm.newrelic&&(n.gm.newrelic=n.gm.NREUM),n.gm.NREUM}function s(){let e=a();return e.o||(e.o={ST:n.gm.setTimeout,SI:n.gm.setImmediate,CT:n.gm.clearTimeout,XHR:n.gm.XMLHttpRequest,REQ:n.gm.Request,EV:n.gm.Event,PR:n.gm.Promise,MO:n.gm.MutationObserver,FETCH:n.gm.fetch,WS:n.gm.WebSocket}),e}function c(e,t){let r=a();r.initializedAgents??={},t.initializedAt={ms:(0,i.t)(),date:new Date},r.initializedAgents[e]=t}function u(e){let t=a();return t.initializedAgents?.[e]}function l(e,t){a()[e]=t}function d(){return function(){let e=a();const t=e.info||{};e.info={beacon:o.beacon,errorBeacon:o.errorBeacon,...t}}(),function(){let e=a();const t=e.init||{};e.init={...t}}(),s(),function(){let e=a();const t=e.loader_config||{};e.loader_config={...t}}(),a()}},843:(e,t,r)=>{"use strict";r.d(t,{u:()=>i});var n=r(878);function i(e,t=!1,r,i){(0,n.DD)("visibilitychange",(function(){if(t)return void("hidden"===document.visibilityState&&e());e(document.visibilityState)}),r,i)}},434:(e,t,r)=>{"use strict";r.d(t,{Jt:()=>o,YM:()=>c});var n=r(836),i=r(607);const o="nr@original:".concat(i.W);var a=Object.prototype.hasOwnProperty,s=!1;function c(e,t){return e||(e=n.ee),r.inPlace=function(e,t,n,i,o){n||(n="");const a="-"===n.charAt(0);for(let s=0;s<t.length;s++){const c=t[s],u=e[c];l(u)||(e[c]=r(u,a?c+n:n,i,c,o))}},r.flag=o,r;function r(t,r,n,s,c){return l(t)?t:(r||(r=""),nrWrapper[o]=t,function(e,t,r){if(Object.defineProperty&&Object.keys)try{return Object.keys(e).forEach((function(r){Object.defineProperty(t,r,{get:function(){return e[r]},set:function(t){return e[r]=t,t}})})),t}catch(e){u([e],r)}for(var n in e)a.call(e,n)&&(t[n]=e[n])}(t,nrWrapper,e),nrWrapper);function nrWrapper(){var o,a,l,d;try{a=this,o=[...arguments],l="function"==typeof n?n(o,a):n||{}}catch(t){u([t,"",[o,a,s],l],e)}i(r+"start",[o,a,s],l,c);try{return d=t.apply(a,o)}catch(e){throw i(r+"err",[o,a,e],l,c),e}finally{i(r+"end",[o,a,d],l,c)}}}function i(r,n,i,o){if(!s||t){var a=s;s=!0;try{e.emit(r,n,i,t,o)}catch(t){u([t,r,n,i],e)}s=a}}}function u(e,t){t||(t=n.ee);try{t.emit("internal-error",e)}catch(e){}}function l(e){return!(e&&"function"==typeof e&&e.apply&&!e[o])}},993:(e,t,r)=>{"use strict";r.d(t,{A$:()=>o,ET:()=>a,p_:()=>i});var n=r(860);const i={ERROR:"ERROR",WARN:"WARN",INFO:"INFO",DEBUG:"DEBUG",TRACE:"TRACE"},o={OFF:0,ERROR:1,WARN:2,INFO:3,DEBUG:4,TRACE:5},a="log";n.K7.logging},773:(e,t,r)=>{"use strict";r.d(t,{z_:()=>o,XG:()=>s,TZ:()=>n,rs:()=>i,xV:()=>a});r(154),r(566),r(384);const n=r(860).K7.metrics,i="sm",o="cm",a="storeSupportabilityMetrics",s="storeEventMetrics"},630:(e,t,r)=>{"use strict";r.d(t,{T:()=>n});const n=r(860).K7.pageViewEvent},782:(e,t,r)=>{"use strict";r.d(t,{T:()=>n});const n=r(860).K7.pageViewTiming},344:(e,t,r)=>{"use strict";r.d(t,{G4:()=>i});var n=r(614);r(860).K7.sessionReplay;const i={RECORD:"recordReplay",PAUSE:"pauseReplay",REPLAY_RUNNING:"replayRunning",ERROR_DURING_REPLAY:"errorDuringReplay"};n.g.ERROR,n.g.FULL,n.g.OFF},234:(e,t,r)=>{"use strict";r.d(t,{W:()=>o});var n=r(836),i=r(687);class o{constructor(e,t){this.agentIdentifier=e,this.ee=n.ee.get(e),this.featureName=t,this.blocked=!1}deregisterDrain(){(0,i.x3)(this.agentIdentifier,this.featureName)}}},603:(e,t,r)=>{"use strict";r.d(t,{j:()=>K});var n=r(860),i=r(555),o=r(371),a=r(908),s=r(836),c=r(687),u=r(289),l=r(154),d=r(944),f=r(773),g=r(384),p=r(344);const m=["setErrorHandler","finished","addToTrace","addRelease","recordCustomEvent","addPageAction","setCurrentRouteName","setPageViewName","setCustomAttribute","interaction","noticeError","setUserId","setApplicationVersion","start",p.G4.RECORD,p.G4.PAUSE,"log","wrapLogger"],h=["setErrorHandler","finished","addToTrace","addRelease"];var v=r(863),b=r(614),y=r(993);var w=r(646),R=r(434);const A=new Map;function E(e,t,r,n){if("object"!=typeof t||!t||"string"!=typeof r||!r||"function"!=typeof t[r])return(0,d.R)(29);const i=function(e){return(e||s.ee).get("logger")}(e),o=(0,R.YM)(i),a=new w.y(s.P);a.level=n.level,a.customAttributes=n.customAttributes;const c=t[r]?.[R.Jt]||t[r];return A.set(c,a),o.inPlace(t,[r],"wrap-logger-",(()=>A.get(c))),i}function _(){const e=(0,g.pV)();m.forEach((t=>{e[t]=(...r)=>function(t,...r){let n=[];return Object.values(e.initializedAgents).forEach((e=>{e&&e.api?e.exposed&&e.api[t]&&n.push(e.api[t](...r)):(0,d.R)(38,t)})),n.length>1?n:n[0]}(t,...r)}))}const x={};function N(e,t,g=!1){t||(0,c.Ak)(e,"api");const m={};var w=s.ee.get(e),R=w.get("tracer");x[e]=b.g.OFF,w.on(p.G4.REPLAY_RUNNING,(t=>{x[e]=t}));var A="api-",_=A+"ixn-";function N(t,r,n,o){const a=(0,i.Vp)(e);return null===r?delete a.jsAttributes[t]:(0,i.x1)(e,{...a,jsAttributes:{...a.jsAttributes,[t]:r}}),j(A,n,!0,o||null===r?"session":void 0)(t,r)}function k(){}m.log=function(e,{customAttributes:t={},level:r=y.p_.INFO}={}){(0,a.p)(f.xV,["API/log/called"],void 0,n.K7.metrics,w),function(e,t,r={},i=y.p_.INFO){(0,a.p)(f.xV,["API/logging/".concat(i.toLowerCase(),"/called")],void 0,n.K7.metrics,e),(0,a.p)(y.ET,[(0,v.t)(),t,r,i],void 0,n.K7.logging,e)}(w,e,t,r)},m.wrapLogger=(e,t,{customAttributes:r={},level:i=y.p_.INFO}={})=>{(0,a.p)(f.xV,["API/wrapLogger/called"],void 0,n.K7.metrics,w),E(w,e,t,{customAttributes:r,level:i})},h.forEach((e=>{m[e]=j(A,e,!0,"api")})),m.addPageAction=j(A,"addPageAction",!0,n.K7.genericEvents),m.recordCustomEvent=j(A,"recordCustomEvent",!0,n.K7.genericEvents),m.setPageViewName=function(t,r){if("string"==typeof t)return"/"!==t.charAt(0)&&(t="/"+t),(0,o.f)(e).customTransaction=(r||"http://custom.transaction")+t,j(A,"setPageViewName",!0)()},m.setCustomAttribute=function(e,t,r=!1){if("string"==typeof e){if(["string","number","boolean"].includes(typeof t)||null===t)return N(e,t,"setCustomAttribute",r);(0,d.R)(40,typeof t)}else(0,d.R)(39,typeof e)},m.setUserId=function(e){if("string"==typeof e||null===e)return N("enduser.id",e,"setUserId",!0);(0,d.R)(41,typeof e)},m.setApplicationVersion=function(e){if("string"==typeof e||null===e)return N("application.version",e,"setApplicationVersion",!1);(0,d.R)(42,typeof e)},m.start=()=>{try{(0,a.p)(f.xV,["API/start/called"],void 0,n.K7.metrics,w),w.emit("manual-start-all")}catch(e){(0,d.R)(23,e)}},m[p.G4.RECORD]=function(){(0,a.p)(f.xV,["API/recordReplay/called"],void 0,n.K7.metrics,w),(0,a.p)(p.G4.RECORD,[],void 0,n.K7.sessionReplay,w)},m[p.G4.PAUSE]=function(){(0,a.p)(f.xV,["API/pauseReplay/called"],void 0,n.K7.metrics,w),(0,a.p)(p.G4.PAUSE,[],void 0,n.K7.sessionReplay,w)},m.interaction=function(e){return(new k).get("object"==typeof e?e:{})};const T=k.prototype={createTracer:function(e,t){var r={},i=this,o="function"==typeof t;return(0,a.p)(f.xV,["API/createTracer/called"],void 0,n.K7.metrics,w),g||(0,a.p)(_+"tracer",[(0,v.t)(),e,r],i,n.K7.spa,w),function(){if(R.emit((o?"":"no-")+"fn-start",[(0,v.t)(),i,o],r),o)try{return t.apply(this,arguments)}catch(e){const t="string"==typeof e?new Error(e):e;throw R.emit("fn-err",[arguments,this,t],r),t}finally{R.emit("fn-end",[(0,v.t)()],r)}}}};function j(e,t,r,i){return function(){return(0,a.p)(f.xV,["API/"+t+"/called"],void 0,n.K7.metrics,w),i&&(0,a.p)(e+t,[r?(0,v.t)():performance.now(),...arguments],r?null:this,i,w),r?void 0:this}}function I(){r.e(296).then(r.bind(r,778)).then((({setAPI:t})=>{t(e),(0,c.Ze)(e,"api")})).catch((e=>{(0,d.R)(27,e),w.abort()}))}return["actionText","setName","setAttribute","save","ignore","onEnd","getContext","end","get"].forEach((e=>{T[e]=j(_,e,void 0,g?n.K7.softNav:n.K7.spa)})),m.setCurrentRouteName=g?j(_,"routeName",void 0,n.K7.softNav):j(A,"routeName",!0,n.K7.spa),m.noticeError=function(t,r){"string"==typeof t&&(t=new Error(t)),(0,a.p)(f.xV,["API/noticeError/called"],void 0,n.K7.metrics,w),(0,a.p)("err",[t,(0,v.t)(),!1,r,!!x[e]],void 0,n.K7.jserrors,w)},l.RI?(0,u.GG)((()=>I()),!0):I(),m}var k=r(217),T=r(122);const j={accountID:void 0,trustKey:void 0,agentID:void 0,licenseKey:void 0,applicationID:void 0,xpid:void 0},I={};var O=r(284);const S=e=>{const t=e.startsWith("http");e+="/",r.p=t?e:"https://"+e};let P=!1;function K(e,t={},r,n){let{init:a,info:c,loader_config:u,runtime:d={},exposed:f=!0}=t;d.loaderType=r;const p=(0,g.pV)();c||(a=p.init,c=p.info,u=p.loader_config),(0,k.xN)(e.agentIdentifier,a||{}),function(e,t){if(!e)throw new Error("All loader-config objects require an agent identifier!");I[e]=(0,T.a)(t,j);const r=(0,g.nY)(e);r&&(r.loader_config=I[e])}(e.agentIdentifier,u||{}),c.jsAttributes??={},l.bv&&(c.jsAttributes.isWorker=!0),(0,i.x1)(e.agentIdentifier,c);const m=(0,k.D0)(e.agentIdentifier),h=[c.beacon,c.errorBeacon];P||(m.proxy.assets&&(S(m.proxy.assets),h.push(m.proxy.assets)),m.proxy.beacon&&h.push(m.proxy.beacon),_(),(0,g.US)("activatedFeatures",O.B),e.runSoftNavOverSpa&&=!0===m.soft_navigations.enabled&&m.feature_flags.includes("soft_nav")),d.denyList=[...m.ajax.deny_list||[],...m.ajax.block_internal?h:[]],d.ptid=e.agentIdentifier,(0,o.V)(e.agentIdentifier,d),e.ee=s.ee.get(e.agentIdentifier),void 0===e.api&&(e.api=N(e.agentIdentifier,n,e.runSoftNavOverSpa)),void 0===e.exposed&&(e.exposed=f),P=!0}},374:(e,t,r)=>{r.nc=(()=>{try{return document?.currentScript?.nonce}catch(e){}return""})()},860:(e,t,r)=>{"use strict";r.d(t,{$J:()=>u,K7:()=>s,P3:()=>c,XX:()=>i,qY:()=>n,v4:()=>a});const n="events",i="jserrors",o="browser/blobs",a="rum",s={ajax:"ajax",genericEvents:"generic_events",jserrors:i,logging:"logging",metrics:"metrics",pageAction:"page_action",pageViewEvent:"page_view_event",pageViewTiming:"page_view_timing",sessionReplay:"session_replay",sessionTrace:"session_trace",softNav:"soft_navigations",spa:"spa"},c={[s.pageViewEvent]:1,[s.pageViewTiming]:2,[s.metrics]:3,[s.jserrors]:4,[s.spa]:5,[s.ajax]:6,[s.sessionTrace]:7,[s.softNav]:8,[s.sessionReplay]:9,[s.logging]:10,[s.genericEvents]:11},u={[s.pageViewEvent]:a,[s.pageViewTiming]:n,[s.ajax]:n,[s.spa]:n,[s.softNav]:n,[s.metrics]:i,[s.jserrors]:i,[s.sessionTrace]:o,[s.sessionReplay]:o,[s.logging]:"browser/logs",[s.genericEvents]:"ins"}}},n={};function i(e){var t=n[e];if(void 0!==t)return t.exports;var o=n[e]={exports:{}};return r[e](o,o.exports,i),o.exports}i.m=r,i.d=(e,t)=>{for(var r in t)i.o(t,r)&&!i.o(e,r)&&Object.defineProperty(e,r,{enumerable:!0,get:t[r]})},i.f={},i.e=e=>Promise.all(Object.keys(i.f).reduce(((t,r)=>(i.f[r](e,t),t)),[])),i.u=e=>"nr-rum-1.283.2.min.js",i.o=(e,t)=>Object.prototype.hasOwnProperty.call(e,t),e={},t="NRBA-1.283.2.PROD:",i.l=(r,n,o,a)=>{if(e[r])e[r].push(n);else{var s,c;if(void 0!==o)for(var u=document.getElementsByTagName("script"),l=0;l<u.length;l++){var d=u[l];if(d.getAttribute("src")==r||d.getAttribute("data-webpack")==t+o){s=d;break}}if(!s){c=!0;var f={296:"sha512-2Y8GMAOGF658KnXzOZ/v+DlLch8TBFvV0tTNnOy9wrpvtDa1t5CdZMyX+LubTymBlzPp6NUjllBghMCZqXBPmg=="};(s=document.createElement("script")).charset="utf-8",s.timeout=120,i.nc&&s.setAttribute("nonce",i.nc),s.setAttribute("data-webpack",t+o),s.src=r,0!==s.src.indexOf(window.location.origin+"/")&&(s.crossOrigin="anonymous"),f[a]&&(s.integrity=f[a])}e[r]=[n];var g=(t,n)=>{s.onerror=s.onload=null,clearTimeout(p);var i=e[r];if(delete e[r],s.parentNode&&s.parentNode.removeChild(s),i&&i.forEach((e=>e(n))),t)return t(n)},p=setTimeout(g.bind(null,void 0,{type:"timeout",target:s}),12e4);s.onerror=g.bind(null,s.onerror),s.onload=g.bind(null,s.onload),c&&document.head.appendChild(s)}},i.r=e=>{"undefined"!=typeof Symbol&&Symbol.toStringTag&&Object.defineProperty(e,Symbol.toStringTag,{value:"Module"}),Object.defineProperty(e,"__esModule",{value:!0})},i.p="https://js-agent.newrelic.com/",(()=>{var e={374:0,840:0};i.f.j=(t,r)=>{var n=i.o(e,t)?e[t]:void 0;if(0!==n)if(n)r.push(n[2]);else{var o=new Promise(((r,i)=>n=e[t]=[r,i]));r.push(n[2]=o);var a=i.p+i.u(t),s=new Error;i.l(a,(r=>{if(i.o(e,t)&&(0!==(n=e[t])&&(e[t]=void 0),n)){var o=r&&("load"===r.type?"missing":r.type),a=r&&r.target&&r.target.src;s.message="Loading chunk "+t+" failed.\n("+o+": "+a+")",s.name="ChunkLoadError",s.type=o,s.request=a,n[1](s)}}),"chunk-"+t,t)}};var t=(t,r)=>{var n,o,[a,s,c]=r,u=0;if(a.some((t=>0!==e[t]))){for(n in s)i.o(s,n)&&(i.m[n]=s[n]);if(c)c(i)}for(t&&t(r);u<a.length;u++)o=a[u],i.o(e,o)&&e[o]&&e[o][0](),e[o]=0},r=self["webpackChunk:NRBA-1.283.2.PROD"]=self["webpackChunk:NRBA-1.283.2.PROD"]||[];r.forEach(t.bind(null,0)),r.push=t.bind(null,r.push.bind(r))})(),(()=>{"use strict";i(374);var e=i(944),t=i(344),r=i(566);class n{agentIdentifier;constructor(){this.agentIdentifier=(0,r.LA)(16)}#e(t,...r){if("function"==typeof this.api?.[t])return this.api[t](...r);(0,e.R)(35,t)}addPageAction(e,t){return this.#e("addPageAction",e,t)}recordCustomEvent(e,t){return this.#e("recordCustomEvent",e,t)}setPageViewName(e,t){return this.#e("setPageViewName",e,t)}setCustomAttribute(e,t,r){return this.#e("setCustomAttribute",e,t,r)}noticeError(e,t){return this.#e("noticeError",e,t)}setUserId(e){return this.#e("setUserId",e)}setApplicationVersion(e){return this.#e("setApplicationVersion",e)}setErrorHandler(e){return this.#e("setErrorHandler",e)}addRelease(e,t){return this.#e("addRelease",e,t)}log(e,t){return this.#e("log",e,t)}}class o extends n{#e(t,...r){if("function"==typeof this.api?.[t])return this.api[t](...r);(0,e.R)(35,t)}start(){return this.#e("start")}finished(e){return this.#e("finished",e)}recordReplay(){return this.#e(t.G4.RECORD)}pauseReplay(){return this.#e(t.G4.PAUSE)}addToTrace(e){return this.#e("addToTrace",e)}setCurrentRouteName(e){return this.#e("setCurrentRouteName",e)}interaction(){return this.#e("interaction")}wrapLogger(e,t,r){return this.#e("wrapLogger",e,t,r)}}var a=i(860),s=i(217);const c=Object.values(a.K7);function u(e){const t={};return c.forEach((r=>{t[r]=function(e,t){return!0===(0,s.gD)(t,"".concat(e,".enabled"))}(r,e)})),t}var l=i(603);var d=i(687),f=i(234),g=i(289),p=i(154),m=i(384);const h=e=>p.RI&&!0===(0,s.gD)(e,"privacy.cookies_enabled");function v(e){return!!(0,m.dV)().o.MO&&h(e)&&!0===(0,s.gD)(e,"session_trace.enabled")}var b=i(389);class y extends f.W{constructor(e,t,r=!0){super(e.agentIdentifier,t),this.auto=r,this.abortHandler=void 0,this.featAggregate=void 0,this.onAggregateImported=void 0,!1===e.init[this.featureName].autoStart&&(this.auto=!1),this.auto?(0,d.Ak)(e.agentIdentifier,t):this.ee.on("manual-start-all",(0,b.J)((()=>{(0,d.Ak)(e.agentIdentifier,this.featureName),this.auto=!0,this.importAggregator(e)})))}importAggregator(t,r={}){if(this.featAggregate||!this.auto)return;let n;this.onAggregateImported=new Promise((e=>{n=e}));const o=async()=>{let o;try{if(h(this.agentIdentifier)){const{setupAgentSession:e}=await i.e(296).then(i.bind(i,861));o=e(t)}}catch(t){(0,e.R)(20,t),this.ee.emit("internal-error",[t]),this.featureName===a.K7.sessionReplay&&this.abortHandler?.()}try{if(!this.#t(this.featureName,o))return(0,d.Ze)(this.agentIdentifier,this.featureName),void n(!1);const{lazyFeatureLoader:e}=await i.e(296).then(i.bind(i,103)),{Aggregate:a}=await e(this.featureName,"aggregate");this.featAggregate=new a(t,r),t.runtime.harvester.initializedAggregates.push(this.featAggregate),n(!0)}catch(t){(0,e.R)(34,t),this.abortHandler?.(),(0,d.Ze)(this.agentIdentifier,this.featureName,!0),n(!1),this.ee&&this.ee.abort()}};p.RI?(0,g.GG)((()=>o()),!0):o()}#t(e,t){switch(e){case a.K7.sessionReplay:return v(this.agentIdentifier)&&!!t;case a.K7.sessionTrace:return!!t;default:return!0}}}var w=i(630);class R extends y{static featureName=w.T;constructor(e,t=!0){super(e,w.T,t),this.importAggregator(e)}}var A=i(908),E=i(843),_=i(878),x=i(782),N=i(863);class k extends y{static featureName=x.T;constructor(e,t=!0){super(e,x.T,t),p.RI&&((0,E.u)((()=>(0,A.p)("docHidden",[(0,N.t)()],void 0,x.T,this.ee)),!0),(0,_.sp)("pagehide",(()=>(0,A.p)("winPagehide",[(0,N.t)()],void 0,x.T,this.ee))),this.importAggregator(e))}}var T=i(773);class j extends y{static featureName=T.TZ;constructor(e,t=!0){super(e,T.TZ,t),this.importAggregator(e)}}new class extends o{constructor(t){super(),p.gm?(this.features={},(0,m.bQ)(this.agentIdentifier,this),this.desiredFeatures=new Set(t.features||[]),this.desiredFeatures.add(R),this.runSoftNavOverSpa=[...this.desiredFeatures].some((e=>e.featureName===a.K7.softNav)),(0,l.j)(this,t,t.loaderType||"agent"),this.run()):(0,e.R)(21)}get config(){return{info:this.info,init:this.init,loader_config:this.loader_config,runtime:this.runtime}}run(){try{const t=u(this.agentIdentifier),r=[...this.desiredFeatures];r.sort(((e,t)=>a.P3[e.featureName]-a.P3[t.featureName])),r.forEach((r=>{if(!t[r.featureName]&&r.featureName!==a.K7.pageViewEvent)return;if(this.runSoftNavOverSpa&&r.featureName===a.K7.spa)return;if(!this.runSoftNavOverSpa&&r.featureName===a.K7.softNav)return;const n=function(e){switch(e){case a.K7.ajax:return[a.K7.jserrors];case a.K7.sessionTrace:return[a.K7.ajax,a.K7.pageViewEvent];case a.K7.sessionReplay:return[a.K7.sessionTrace];case a.K7.pageViewTiming:return[a.K7.pageViewEvent];default:return[]}}(r.featureName).filter((e=>!(e in this.features)));n.length>0&&(0,e.R)(36,{targetFeature:r.featureName,missingDependencies:n}),this.features[r.featureName]=new r(this)}))}catch(t){(0,e.R)(22,t);for(const e in this.features)this.features[e].abortHandler?.();const r=(0,m.Zm)();delete r.initializedAgents[this.agentIdentifier]?.api,delete r.initializedAgents[this.agentIdentifier]?.features,delete this.sharedAggregator;return r.ee.get(this.agentIdentifier).abort(),!1}}}({features:[R,k,j],loaderType:"lite"})})()})();</script>
<noscript><style>form.antibot * :not(.antibot-message) { display: none !important; }</style>
</noscript><script async src="https://www.googletagmanager.com/gtag/js?id=G-HEQ0YF2VYL"></script>
<script>window.dataLayer = window.dataLayer || [];function gtag(){dataLayer.push(arguments)};gtag("js", new Date());gtag("set", "developer_id.dMDhkMT", true);gtag('set', {'cookie_flags': 'SameSite=None;Secure', 'cookie_domain': 'www.nist.gov'});gtag("config", "G-HEQ0YF2VYL", {"groups":"default","page_placeholder":"PLACEHOLDER_page_location","link_attribution":true,"allow_ad_personalization_signals":false});gtag("config", "G-CSLL4ZEK4L", {"groups":"default","page_placeholder":"PLACEHOLDER_page_location","link_attribution":true,"allow_ad_personalization_signals":false});gtag("event", "custom", {"node_title":"NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies","node_id":"1652361","blog_author":"Denis Bergeron","content_type":"Blog entry"});</script>
<meta name="description" content="From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots" />
<link rel="canonical" href="https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies" />
<link rel="shortlink" href="https://www.nist.gov/node/1652361" />
<meta name="citation_title" content="NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies | NIST" />
<meta property="og:site_name" content="NIST" />
<meta property="og:type" content="Article" />
<meta property="og:url" content="https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies" />
<meta property="og:title" content="NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies" />
<meta property="og:description" content="From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots" />
<meta property="og:image" content="https://www.nist.gov/sites/default/files/styles/social/public/images/2021/02/16/Bergeron%20l-shield.jpg?itok=Fm4N1lNP" />
<meta property="og:image" content="https://www.nist.gov/themes/custom/nist_www/img/homepage/nist_mark.png" />
<meta property="og:image:width" content="1073" />
<meta property="og:image:height" content="671" />
<meta property="og:image:alt" content="Denis Bergeron working behind an L-shield with a syringe containing a radiopharmaceutical." />
<meta property="article:author" content="Denis Bergeron" />
<meta property="article:tag" content="radioactivity" />
<meta property="article:published_time" content="2021-02-18T07:00-05:00" />
<meta property="article:modified_time" content="2025-02-14T11:01-05:00" />
<meta name="dcterms.title" content="NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies" />
<meta name="dcterms.creator" content="Denis Bergeron" />
<meta name="dcterms.description" content="From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots" />
<meta name="dcterms.publisher" content="Denis Bergeron" />
<meta name="dcterms.contributor" content="NIST" />
<meta name="dcterms.date" content="2021-02-18T07:00-05:00" />
<meta name="dcterms.type" content="text" />
<meta name="dcterms.format" content="text/html" />
<meta name="dcterms.identifier" content="https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies" />
<meta name="dcterms.source" content="NIST" />
<meta name="dcterms.created" content="2021-02-18T07:00-05:00" />
<meta name="dcterms.modified" content="2025-02-14T11:01-05:00" />
<meta name="twitter:card" content="summary_large_image" />
<meta name="twitter:description" content="From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots" />
<meta name="twitter:site" content="NIST" />
<meta name="twitter:title" content="NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies" />
<meta name="google-site-verification" content="QMu0ODkER3rN5hLcMLqNVf7e3bkjYsNLTuhqfH48jCA" />
<meta name="Generator" content="Drupal 10 (https://www.drupal.org)" />
<meta name="MobileOptimized" content="width" />
<meta name="HandheldFriendly" content="true" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<meta name="nist_search_modified" class="elastic" content="2025-02-14T11:01:00-05:00" />
<script type="application/ld+json">{
"@context": "https://schema.org",
"@graph": [
{
"@type": "Article",
"@id": "https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies",
"headline": "NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies",
"name": "NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies",
"description": "From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots.",
"image": {
"@type": "ImageObject",
"url": "https://www.nist.gov/sites/default/files/styles/social/public/images/2021/02/16/Bergeron%20l-shield.jpg?itok=Fm4N1lNP",
"width": "1073",
"height": "671"
},
"datePublished": "2021-02-18T07:00-05:00",
"dateModified": "2025-02-14T11:01-05:00",
"author": {
"@type": "Person",
"@id": "https://www.nist.gov/blogs/taking-measure/authors/denis-bergeron-0",
"name": "Denis Bergeron",
"url": "https://www.nist.gov/blogs/taking-measure/authors/denis-bergeron-0"
},
"publisher": {
"@type": "GovernmentOrganization",
"@id": "https://www.nist.gov/",
"name": "National Institute of Standards and Technology",
"url": "https://www.nist.gov/"
}
}
]
}</script>
<meta name="nist_search_bundle" class="elastic" content="blog" />
<link rel="icon" href="/themes/custom/nist_www/favicon.ico" type="image/vnd.microsoft.icon" />
<title>NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies | NIST</title>
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_hKAD9a0878O1Pdb6alKtCmESLiUtQmrBX15rQUvSgOA.css?delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKotCNFaYTW9fazW5ctIYRH3i9CWoPJmM3H3x0oSXWV1II9sOD4CUdooUj2mRQiY2Cqq9NTDcvQKr75fmGJwB9t7_2L8WkX3-e2b8DTDd1B2NW_9zS8d75dCiyVZkpuJjZsPsFmNCqpJAIOBTPBFToYDKfsFkarJAe200vFJH8NCqUmSoYvWkVdRQ" />
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_kGS0ApDpFo-_3JI4Ijxg4RCWlTqsImK3lqH7bCv5v2U.css?delta=1&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKotCNFaYTW9fazW5ctIYRH3i9CWoPJmM3H3x0oSXWV1II9sOD4CUdooUj2mRQiY2Cqq9NTDcvQKr75fmGJwB9t7_2L8WkX3-e2b8DTDd1B2NW_9zS8d75dCiyVZkpuJjZsPsFmNCqpJAIOBTPBFToYDKfsFkarJAe200vFJH8NCqUmSoYvWkVdRQ" />
<link rel="stylesheet" media="print" href="/sites/default/files/css/css_-IXwLuTUdm8IGHxib8GX8wWKw3LjKsNWSYYskZ5fEGg.css?delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKotCNFaYTW9fazW5ctIYRH3i9CWoPJmM3H3x0oSXWV1II9sOD4CUdooUj2mRQiY2Cqq9NTDcvQKr75fmGJwB9t7_2L8WkX3-e2b8DTDd1B2NW_9zS8d75dCiyVZkpuJjZsPsFmNCqpJAIOBTPBFToYDKfsFkarJAe200vFJH8NCqUmSoYvWkVdRQ" />
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_RS8YGnRq2Xi5aD-GQC3GKwBe6bOWBBmEmXrb2xB5FMM.css?delta=3&amp;language=en&amp;theme=nist_www&amp;include=eJxNTgsOwyAIvZCpRzKotCNFaYTW9fazW5ctIYRH3i9CWoPJmM3H3x0oSXWV1II9sOD4CUdooUj2mRQiY2Cqq9NTDcvQKr75fmGJwB9t7_2L8WkX3-e2b8DTDd1B2NW_9zS8d75dCiyVZkpuJjZsPsFmNCqpJAIOBTPBFToYDKfsFkarJAe200vFJH8NCqUmSoYvWkVdRQ" />
<script src="/sites/default/files/js/js_GM8kl6wk698qKTTwusj83bCoGHHtOZ1UinjY1sE_Qbk.js?scope=header&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxdjdEOwiAMRX9o2E9qyqhYBboAE_17YW7RLOGBc3p7a2l-YNX-FrC_P97L5FV9YKRE4V1lLnAWU5JS8SrdOW0pKDmsuZdI8uDpOy5SWeKS9clwFuPK5uqNI_e7GixljOrASSHbi4Okx5YBH9RSMPsK3Jgc5wOxtfaX4Fcdi-DyulC47DjNGiOneugdjX2bp3Dj_G2O5JNcZZ6GLHhf44I9t8LGZrAZ_AFBzXxL"></script>
</head>
<body class="node-1652361">
<a href="#main-content" class="visually-hidden focusable" data-elastic-exclude>
Skip to main content
</a>
<div class="dialog-off-canvas-main-canvas" data-off-canvas-main-canvas>
<!-- nist-index-ignore-start -->
<section data-elastic-exclude class="usa-banner" aria-label="Official government website">
<div class="usa-accordion">
<header class="usa-banner__header">
<div class="usa-banner__inner">
<div class="grid-col-auto">
<img class="usa-banner__header-flag" src="/libraries/nist-component-library/dist/img/us_flag_small.png" alt="U.S. flag">
</div>
<div class="grid-col-fill tablet:grid-col-auto">
<p class="usa-banner__header-text">An official website of the United States government</p>
<p class="usa-banner__header-action" aria-hidden="true">Here’s how you know</p>
</div>
<button class="usa-accordion__button usa-banner__button" aria-expanded="false" aria-controls="gov-banner-default">
<span class="usa-banner__button-text">Here’s how you know</span>
</button>
</div>
</header>
<div class="usa-banner__content usa-accordion__content" id="gov-banner-default">
<div class="grid-row grid-gap-lg">
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="/libraries/nist-component-library/dist/img/icon-dot-gov.svg" role="img" alt="" aria-hidden="true">
<div class="usa-media-block__body">
<p>
<strong>Official websites use .gov</strong>
<br/>
A <strong>.gov</strong> website belongs to an official government organization in the United States.
</p>
</div>
</div>
<div class="usa-banner__guidance tablet:grid-col-6">
<img class="usa-banner__icon usa-media-block__img" src="/libraries/nist-component-library/dist/img/icon-https.svg" role="img" alt="" aria-hidden="true">
<div class="usa-media-block__body">
<p>
<strong>Secure .gov websites use HTTPS</strong>
<br/>
A <strong>lock</strong> ( <span class="icon-lock">
<svg xmlns="http://www.w3.org/2000/svg" width="52" height="64" viewbox="0 0 52 64" class="usa-banner__lock-image" role="img" aria-labelledby="banner-lock-title banner-lock-description" focusable="false">
<title id="banner-lock-title">Lock</title>
<desc id="banner-lock-description">A locked padlock</desc><path fill="#000000" fill-rule="evenodd" d="M26 0c10.493 0 19 8.507 19 19v9h3a4 4 0 0 1 4 4v28a4 4 0 0 1-4 4H4a4 4 0 0 1-4-4V32a4 4 0 0 1 4-4h3v-9C7 8.507 15.507 0 26 0zm0 8c-5.979 0-10.843 4.77-10.996 10.712L15 19v9h22v-9c0-6.075-4.925-11-11-11z"/></svg>
</span>
) or <strong>https://</strong> means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
</p>
</div>
</div>
</div>
</div>
</div>
</section>
<!-- nist-index-ignore-end -->
<div data-elastic-exclude>
<!-- nist-index-ignore-start -->
<div class="nist-print-header" style="display:none;">
<p class="nist-print-header__url">https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies</p>
<img class="nist-print-header__logo" width="289" height="38" src="/libraries/nist-component-library/dist/img/logo/nist_logo_sidestack.svg" alt="National Institute of Standards and Technology" />
</div>
<div class="usa-overlay"></div>
<header class="usa-header nist-header--www nist-header--minimal" role="banner">
<div class="usa-navbar">
<div class="usa-logo flex-fill">
<a href="/" title="National Institute of Standards and Technology" aria-label="Home">
<img src="/libraries/nist-component-library/dist/img/logo/logo.svg" alt="National Institute of Standards and Technology" width="300px" height="80px" />
</a>
</div>
<div class="usa-header__right grid-row flex-auto">
<div class="grid-col-fill nist-header__search-group">
<form class="usa-search usa-search--small"
accept-charset="UTF-8"
action="/search"
id="search_form"
method="get">
<div role="search">
<label class="usa-sr-only" for="search-form">Search NIST</label>
<input class="usa-input" id="search-form" type="search" name="s" placeholder="Search NIST" required="" maxlength="128">
<button class="usa-button" type="submit"><img src="/libraries/nist-component-library/dist/img/usa-icons-bg/search--white.svg" class="usa-search__submit-icon" alt="Search"></button>
</div>
</form>
</div>
<div class="grid-col-auto padding-left-1">
<button class="usa-menu-btn">Menu</button>
</div>
</div>
</div>
<nav aria-label="Primary navigation" class="usa-nav">
<div class="usa-nav__inner">
<button class="usa-nav__close">Close</button>
<ul class="usa-nav__primary usa-accordion">
<li class="usa-nav__primary-item">
<a class="usa-nav__link" href="/publications">Publications</a>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-2"><span>What We Do</span></button>
<div id="primary_menu-2" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/topics" class="usa-nav__link">All Topics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/advanced-communications" class="usa-nav__link">Advanced communications</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/artificial-intelligence" class="usa-nav__link">Artificial intelligence</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/bioscience" class="usa-nav__link">Bioscience</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/buildings-construction" class="usa-nav__link">Buildings and construction</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/chemistry" class="usa-nav__link">Chemistry</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/cybersecurity" class="usa-nav__link">Cybersecurity</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/electronics" class="usa-nav__link">Electronics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/energy" class="usa-nav__link">Energy</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/environment" class="usa-nav__link">Environment</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/fire" class="usa-nav__link">Fire</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/forensic-science" class="usa-nav__link">Forensic science</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/health" class="usa-nav__link">Health</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/information-technology" class="usa-nav__link">Information technology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/infrastructure" class="usa-nav__link">Infrastructure</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/manufacturing" class="usa-nav__link">Manufacturing</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/materials" class="usa-nav__link">Materials</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/mathematics-statistics" class="usa-nav__link">Mathematics and statistics</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/metrology" class="usa-nav__link">Metrology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/nanotechnology" class="usa-nav__link">Nanotechnology</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/neutron-research" class="usa-nav__link">Neutron research</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/performance-excellence" class="usa-nav__link">Performance excellence</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/physics" class="usa-nav__link">Physics</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/public-safety" class="usa-nav__link">Public safety</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/quantum-information-science" class="usa-nav__link">Quantum information science</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/resilience" class="usa-nav__link">Resilience</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/standards" class="usa-nav__link">Standards</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/transportation" class="usa-nav__link">Transportation</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-3"><span>Labs &amp; Major Programs</span></button>
<div id="primary_menu-3" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/adlp" class="usa-nav__link">Assoc Director of Laboratory Programs</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories" class="usa-nav__link">Laboratories</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/ctl" class="usa-nav__link">Communications Technology Laboratory</a>
</li>
<li>
<a href="/el" class="usa-nav__link">Engineering Laboratory</a>
</li>
<li>
<a href="/itl" class="usa-nav__link">Information Technology Laboratory</a>
</li>
<li>
<a href="/mml" class="usa-nav__link">Material Measurement Laboratory</a>
</li>
<li>
<a href="/pml" class="usa-nav__link">Physical Measurement Laboratory</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/user-facilities" class="usa-nav__link">User Facilities</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/ncnr" class="usa-nav__link">NIST Center for Neutron Research</a>
</li>
<li>
<a href="/cnst" class="usa-nav__link">CNST NanoFab</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/labs-major-programs/research-test-beds" class="usa-nav__link">Research Test Beds</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories/projects-programs" class="usa-nav__link">Research Projects</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/laboratories/tools-instruments" class="usa-nav__link">Tools &amp; Instruments</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/major-programs" class="usa-nav__link">Major Programs</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/baldrige" class="usa-nav__link">Baldrige Performance Excellence Program</a>
</li>
<li>
<a href="/chips" class="usa-nav__link">CHIPS for America Initiative</a>
</li>
<li>
<a href="/mep" class="usa-nav__link">Manufacturing Extension Partnership (MEP)</a>
</li>
<li>
<a href="/oam" class="usa-nav__link">Office of Advanced Manufacturing</a>
</li>
<li>
<a href="/spo" class="usa-nav__link">Special Programs Office</a>
</li>
<li>
<a href="/tpo" class="usa-nav__link">Technology Partnerships Office</a>
</li>
</ul>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-4"><span>Services &amp; Resources</span></button>
<div id="primary_menu-4" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/content/standards-measurements" class="usa-nav__link">Standards and Measurements</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/calibrations" class="usa-nav__link">Calibration Services</a>
</li>
<li>
<a href="/nvlap" class="usa-nav__link">Laboratory Accreditation (NVLAP)</a>
</li>
<li>
<a href="/nist-quality-system" class="usa-nav__link">Quality System</a>
</li>
<li>
<a href="/srm" class="usa-nav__link">Standard Reference Materials (SRMs)</a>
</li>
<li>
<a href="/sri" class="usa-nav__link">Standard Reference Instruments (SRIs)</a>
</li>
<li>
<a href="/standardsgov" class="usa-nav__link">Standards.gov</a>
</li>
<li>
<a href="/pml/time-and-frequency-division/time-services" class="usa-nav__link">Time Services</a>
</li>
<li>
<a href="/pml/owm" class="usa-nav__link">Office of Weights and Measures</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/services-resources/software" class="usa-nav__link">Software</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/data" class="usa-nav__link">Data</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="https://webbook.nist.gov/chemistry/" class="usa-nav__link">Chemistry WebBook</a>
</li>
<li>
<a href="https://nvd.nist.gov/" class="usa-nav__link">National Vulnerability Database</a>
</li>
<li>
<a href="/pml/productsservices/physical-reference-data" class="usa-nav__link">Physical Reference Data</a>
</li>
<li>
<a href="/srd" class="usa-nav__link">Standard Reference Data (SRD)</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="https://shop.nist.gov/" class="usa-nav__link">Storefront</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/tpo" class="usa-nav__link">License &amp; Patents</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="https://csrc.nist.gov/" class="usa-nav__link">Computer Security Resource Center (CSRC)</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/nist-research-library" class="usa-nav__link">NIST Research Library</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-5"><span>News &amp; Events</span></button>
<div id="primary_menu-5" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/news-events/news" class="usa-nav__link">News</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/news-events/events" class="usa-nav__link">Events</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/blogs" class="usa-nav__link">Blogs</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/feature-stories" class="usa-nav__link">Feature Stories</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/awards" class="usa-nav__link">Awards</a>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/video-gallery" class="usa-nav__link">Video Gallery</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/image-gallery" class="usa-nav__link">Image Gallery</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/pao/media-contacts" class="usa-nav__link">Media Contacts</a>
</li>
</ul>
</div>
</div>
</div>
</li>
<li class="usa-nav__primary-item">
<button class="usa-accordion__button usa-nav__link" aria-expanded="false" aria-controls="primary_menu-6"><span>About NIST</span></button>
<div id="primary_menu-6" class="usa-nav__submenu usa-megamenu">
<div class="grid-row">
<div class="tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/about-nist" class="usa-nav__link">About Us</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/director/leadership" class="usa-nav__link">Leadership</a>
</li>
<li>
<a href="/director/nist-organization-structure" class="usa-nav__link">Organization Structure</a>
</li>
<li>
<a href="/about-nist/budget-planning" class="usa-nav__link">Budget &amp; Planning</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/about-nist/contact-us" class="usa-nav__link">Contact Us</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/about-nist/visit" class="usa-nav__link">Visit</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/careers" class="usa-nav__link">Careers</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="/iaao/academic-affairs-office" class="usa-nav__link">Student programs</a>
</li>
</ul>
</li>
</ul></div><div class="column-break tablet:grid-col-fill"><ul class="usa-nav__submenu-list">
<li class="usa-nav__submenu-item">
<a href="/about-nist/work-nist" class="usa-nav__link">Work with NIST</a>
</li>
<li class="usa-nav__submenu-item">
<a href="/history" class="usa-nav__link">History</a>
<ul class="usa-nav__submenu-list">
<li>
<a href="http://nistdigitalarchives.contentdm.oclc.org/" class="usa-nav__link">NIST Digital Archives</a>
</li>
<li>
<a href="/nist-museum" class="usa-nav__link">NIST Museum</a>
</li>
<li>
<a href="/nist-and-nobel" class="usa-nav__link">NIST and the Nobel</a>
</li>
</ul>
</li>
<li class="usa-nav__submenu-item">
<a href="/education" class="usa-nav__link">Educational Resources</a>
</li>
</ul>
</div>
</div>
</div>
</li>
</ul>
</div>
</nav>
</header>
<!-- nist-index-ignore-end -->
</div>
<div class="grid-container">
</div>
<div
id="block-nist-www-content" class="nist-block"
>
<section
class="nist-page__content usa-section clearfix"
>
<a id="main-content" tabindex="-1"></a>
<div
class="nist-page__region nist-page__region--content-top-full"
>
<div
class="nist-block"
>
<div class="entity-reference">
<div class="nist-blog-header nist-blog-header--purple nist-blog-header--inner">
<div class="nist-blog-header__bkgrd">
<div class="nist-blog-header__main grid-container">
<div class="grid-row">
<h2 class="nist-blog-header__title">
<a href="/blogs/taking-measure"> Taking Measure
</a>
</h2>
<div class="nist-blog-header__tagline">
<p class="text">Just a Standard Blog</p>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
<div class="grid-container margin-top-4">
<div
class="nist-page__region nist-page__region--content-top"
>
<div
class="nist-block"
>
<h1 class="nist-page__title">NIST Radioactivity Measurements Get the Ball Rolling for New Cancer Therapies</h1>
</div>
<div
class="font-body-md"
>
<div class="daterange"><time datetime="2021-02-18T12:00:00Z">February 18, 2021</time>
</div>
</div>
<div
class="nist-block"
>
<span>By: </span>
<a href="/blogs/taking-measure/authors/denis-bergeron-0" hreflang="en">Denis Bergeron</a>
</div>
<div
class="nist-block"
>
<!-- nist-index-ignore-start -->
<div data-elastic-exclude class="nist-block nist-social__wrapper">
<h2 class="nist-social__title">Share</h2>
<div class="social-media-sharing">
<div class="nist-social__wrapper--share">
<div>
<a target="_blank" rel="noopener" href="https://www.facebook.com/share.php?u=https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies"
title="Facebook" class="nist-social nist-social--facebook-gray">
<span>Facebook</span>
</a>
</div>
<div>
<a target="_blank" rel="noopener" href="https://www.linkedin.com/shareArticle?mini=true&amp;url=https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies&amp;source=https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies"
title="Linkedin" class="nist-social nist-social--linkedin-gray">
<span>Linkedin</span>
</a>
</div>
<div>
<a target="_blank" rel="noopener" href="https://x.com/intent/tweet?url=https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies&amp;status=https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies"
title="X.com" class="nist-social nist-social--x-gray">
<span>X.com</span>
</a>
</div>
<div>
<a href="mailto:?subject=NIST.gov&amp;body=Check out this site https://www.nist.gov/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies"
title="Email" class="nist-social nist-social--envelope-gray">
<span>Email</span>
</a>
</div>
</div>
</div>
</div>
<!-- nist-index-ignore-end -->
</div>
</div>
</div>
<div class="grid-container margin-top-4">
<div class="grid-row grid-gap-6">
<div
class="nist-page__region nist-page__region--content tablet-lg:grid-col-8"
>
<div
class="nist-block"
>
<div class="text-with-summary">
<figure class="nist-image--lightbox nist-image" data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2021/02/16/Bergeron%20l-shield.jpg?itok=3IZu0pHA" data-media-id="601916">
<img loading="lazy" src="/sites/default/files/styles/960_x_960_limit/public/images/2021/02/16/Bergeron%20l-shield.jpg?itok=GJSlCg8T" width="960" height="600" alt="Denis Bergeron working behind an L-shield with a syringe containing a radiopharmaceutical." title="Bergeron l-shield" typeof="foaf:Image" />
<figcaption class="nist-image__caption">
<div data-caption-editable="true" class="nist-image__caption-content">
<p><em>Working behind an L-shield with a syringe containing a radiopharmaceutical.</em></p>
</div>
<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
M. Mille
</div>
</figcaption>
</figure>
<p>From the earliest days of radioactivity research, radiation and cancer therapy have gone together like peas and carrots. But <a href="/blogs/taking-measure/minding-your-peas-and-carrots-please-try-home" data-entity-type="node" data-entity-uuid="37adb37f-cb18-4ed1-bb81-f67a80f9e91e" data-entity-substitution="canonical" title="Minding your Peas and Carrots: Please Try This at Home">Zach Levine covered peas and carrots in an earlier blog post</a>, so I will focus on radiation and cancer therapy.</p><p>Shortly after <a href="https://en.wikipedia.org/wiki/Wilhelm_R%C3%B6ntgen">Wilhelm Röntgen</a> discovered the high-energy electromagnetic radiation he called “X-rays” in 1895, their cell-killing power was recognized and harnessed to treat cancer. Similarly, within a few years of the Curies’ discovery of the radioactive element radium, doctors were deploying the energetic particles it emitted to treat skin cancers. By the 1910s, more powerful X-ray tubes were producing beams that could penetrate deeper into the body to treat all sorts of tumors. This “external beam therapy” was on its way to becoming the standard for radiotherapy, largely supplanting radium-based therapies.</p><p>Today, with creative chemistry, radium isotopes (along with radioactive isotopes of other atoms) are making a comeback. Modern external beam approaches are pretty good at limiting damage to healthy neighboring tissue, but it’s a struggle. Emerging alternative therapies use the heaviest of the particles emitted by radioactive isotopes, called alpha particles, which deliver lethal amounts of energy to precisely targeted tissue over very short ranges.</p><p>Before diving too deep into how “alpha therapy” works, I should probably step back to define “alpha particle.” It’s not something most people — even most scientists — think about regularly. In fact, I vividly recall a feeling of panic in 2008 when, on my way to my new office in the Radiation Physics Building at the National Institute of Standards and Technology (NIST), I realized I wasn’t 100% confident I correctly remembered which were the alphas, the betas and the gammas! Which were the big ones? How did I get here?</p><p>The answer to that last question was “bowling,” by the way. You see, I came to NIST in 2006 as a <a href="/iaao/academic-affairs-office/postdoctoral-students-nrc-postdocs" data-entity-type="node" data-entity-uuid="eac2a2fb-45be-4202-9df2-8094fd1c45a2" data-entity-substitution="canonical" title="Postdoctoral Students (NRC Postdocs)">National Research Council (NRC) fellow</a> to study how gold nanoparticles form. I joined the NIST bowling league within a week of arriving, while my wife and I were still living in a hotel room. As my fellowship was ending two years later, I was in the thick of a job hunt, and I was still bowling. So was (now retired) Radioactivity Group leader <a href="/people/michael-p-unterweger" data-entity-type="node" data-entity-uuid="aab29078-5489-49ce-a1c1-1323c56eb4cb" data-entity-substitution="canonical" title="Michael P. Unterweger">Mike Unterweger</a>, who asked me, “Are you afraid of radioactivity?” I answered “No … ,” sent Mike my CV, and soon found myself intrigued by an opportunity to dive into a totally new (to me) field.</p>
<figure class=" align-right nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2021/02/16/Lucy%20Bergeron.jpg?itok=UVeUMLHV" data-media-id="601921">
<img alt="Lucy Bergeron about to bowl" height="480" loading="lazy" src="/sites/default/files/styles/480_x_480_limit/public/images/2021/02/16/Lucy%20Bergeron.jpg?itok=QSfVd-GJ" title="Lucy Bergeron about to bowl" typeof="foaf:Image" width="360">
</div>
<figcaption class="nist-image__caption">Lucy Bergeron, rocking the 6-pound ball at her 6th birthday party. It hit some pins and a couple fell down.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
D. Bergeron/NIST
</div></figcaption>
</figure>
<p>By this time, you’re thinking I’ve digressed, gone off the rails, and there’s no coming back. But wait! I’ll use bowling to help illustrate an important concept. It’s called “linear energy transfer,” and it matters a lot in targeted radiotherapy. Until a few years ago, radioactive drugs used in cancer therapy (“therapeutic radiopharmaceuticals,” usually molecules or particles tagged with a radioactive payload and designed to target cancer in different areas of the body) were mostly based on beta emitters. Beta particles are high-energy electrons given off when a neutron in an atomic nucleus decays into a proton. In cancer therapy, a beta particle bounces around in tissue, losing energy as it scatters. It will typically travel a centimeter or so before losing all its energy. Along the way, chemical bonds are broken, meaning some cells can be killed. Let’s picture a 6-pound bowling ball rattling around as it knocks down a few pins. Cute.</p><p>But what if you can put a 16-pound ball right in the pocket? (Strike!!) That’s targeted alpha therapy. Instead of a lightweight electron, an alpha particle is a highly charged helium nucleus (two protons and two neutrons), about 8,000 times as massive and delivering all its considerable kinetic energy over a few micrometers. An alpha particle will utterly destroy everything in its short path. That’s high linear energy transfer.</p>
<figure class=" align-right nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2021/02/16/Unterweger%20retirement.jpg?itok=Nk05nHA7" data-media-id="601926">
<img alt="Group of people at the Harry S. Truman Bowling Alley" height="360" loading="lazy" src="/sites/default/files/styles/480_x_480_limit/public/images/2021/02/16/Unterweger%20retirement.jpg?itok=fGx0hPCT" title="Unterweger retirement at Harry S. Truman Bowling Alley" typeof="foaf:Image" width="480">
</div>
<figcaption class="nist-image__caption">Here’s me (second from left) delivering a lecture on linear energy transfer to fellow NIST scientists at the White House’s Truman Bowling Alley. We celebrated Mike Unterweger’s retirement with a memorable outing.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
M. Unterweger
</div></figcaption>
</figure>
<p>Smart chemists have been figuring out ways to deliver alpha-particle-emitting radiopharmaceuticals directly to the cells they wish to kill. If everything goes to plan, this approach means killing all the tumor cells without causing any damage to neighboring healthy tissue. This is a step toward the dream of side-effect-free cancer therapy.</p><p>Where does NIST come in? To administer an optimal therapeutic dose, you need to establish a dose-response relationship. While we leave the “response” part to our colleagues in the clinic, the “dose” part comes back to us. And while “dose” is defined in terms of absorbed energy per kilogram (measured in <a href="https://www.nrc.gov/reading-rm/basic-ref/glossary/gray-gy.html">grays</a>), the amount of dose-delivering radioactivity administered to a patient is measured in <a href="https://www.nrc.gov/reading-rm/basic-ref/glossary/becquerel-bq.html">becquerels</a>.</p><p>The becquerel is the SI unit for activity, defined as the number of decays of a particular radionuclide per second. Every radionuclide disintegrates via its own unique decay scheme, meaning that every radionuclide effectively has its own becquerel. And, of course, since our radioactive samples are always decaying away (i.e., they’re radioactive), a measurement of the becquerel is only meaningful when it’s accompanied by a reference time. Along with the activity of my sample right now, I have to tell you what I mean by “right now” and I have to tell you the half-life (the amount of time it takes for half of the atoms to decay) of the particular radionuclide in my sample. Only then can you figure out what activity to expect of my sample when it matters to you. The becquerel is a tricky, ethereal beast. It’s our job at NIST to define that beast as precisely as possible to support all sorts of applications, including therapeutic nuclear medicine.</p>
<figure class=" align-right nist-image--lightbox nist-image" role="group">
<div data-lightbox="https://www.nist.gov/sites/default/files/styles/2800_x_2800_limit/public/images/2021/02/16/radium-224.jpg?itok=IYXIcwTF" data-media-id="601941">
<img alt="a pair of translucent gloved hands hold a small vial containing radium-224 adsorbed on calcium carbonate microparticles. " height="480" loading="lazy" src="/sites/default/files/styles/480_x_480_limit/public/images/2021/02/16/radium-224.jpg?itok=UBc6Fjri" title="radium 224" typeof="foaf:Image" width="360">
</div>
<figcaption class="nist-image__caption">NIST recently developed activity measurement standards for radium-224 adsorbed on calcium carbonate microparticles. A similar formulation is being developed for the targeted treatment of cavitary micrometastases.<div class="nist-image__credit">
<span class="nist-image__credit-label">Credit:</span>
D. Bergeron/NIST
</div></figcaption>
</figure>
<p>As I said, alphas deliver their energy over a very short range, making them “easy” to measure with certain techniques. But don’t worry! There’s enough physics and chemistry here to really keep us on our toes. Some of our biggest challenges come from the complex decay chains we’re encountering. Alpha-emitting isotopes such as radium-223, radium-224 and actinium-211 don’t just spit out an alpha particle and become stable. They decay into atoms that then decay into other atoms that then … you get the idea. They stay radioactive. We have to account for all of the radionuclides in a series of decays in order to measure the activity of the first one. And we do. Using a scheme referred to as the “Bateman equation,” we predict the relative activities of every member in a decay chain (often called the “parent” and its “progeny”) at any given time. With that, and good knowledge of the characteristic radiation of all the progeny, we can make very precise activity measurements.</p><p>Increasingly, NIST is asked to set the standards that will support clinical activity measurements for alpha-emitters. Our measurements will power a new age of precision medicine, making sure that just the right amount of radiation gets just where it needs to be to kill every cancer cell.</p><p>A few years back, at a meeting of the Society of Nuclear Medicine and Molecular Imaging, I sat in on a patient education session that focused on a drug product our group at NIST had worked on. During the Q&amp;A part of the session, a couple of cancer survivors shared their stories, explaining how joining a particular clinical trial had radically changed their lives. I work in a lab, trying to figure out how to solve measurement problems, thinking about some chemistry and some nuclear physics — I had never really given much thought to the individuals on the other end. A year ago, they’d suffered crippling pain and a hopeless prognosis. But here they were, alive and traveling across the country to share their stories at this meeting. The impact NIST measurements can have on people’s lives is … striking.</p>
</div>
</div>
<div
class="nist-block"
>
<div class="nist-tags">
<a href="/blogs/taking-measure/categories/248321">Bioscience</a>,
<a href="/blogs/taking-measure/categories/248416">Chemistry</a>,
<a href="/blogs/taking-measure/categories/248441">Theoretical chemistry and modeling</a>,
<a href="/blogs/taking-measure/categories/248651">Health</a>,
<a href="/blogs/taking-measure/categories/248686">Precision medicine</a>,
<a href="/blogs/taking-measure/categories/248656">Regenerative medicine and advanced therapy</a>,
<a href="/blogs/taking-measure/categories/249241">Physics</a> and
<a href="/blogs/taking-measure/categories/249286">Radiation</a></div>
</div>
<div
class="nist-block"
>
<h2
class="nist-block__title"
>About the author</h2>
<div class="nist-field nist-field--label-hidden entity-reference">
<div class="nist-field__items">
<div class="nist-field__item">
<article
about="/blogs/taking-measure/authors/denis-bergeron-0" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/authors/denis-bergeron-0" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2021/02/05/Denis%20Bergeron.jpg?itok=j6G5gq-1" width="100" height="100" alt="Denis Bergeron" typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/authors/denis-bergeron-0"><span>Denis Bergeron</span>
</a></h3>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"><p><span><span><span>Denis </span></span></span><span><span><span>Bergeron <span>received a B.S. in chemistry from Loyola University New Orleans and a Ph.D. in physical chemistry from the Pennsylvania State University. Following a postdoctoral fellowship at the University of Nottingham, he came to NIST as a National Research Council (NRC) Fellow in 2006 and joined the Radioactivity Group as a research chemist in 2008. His two daughters think a bowling analogy for targeted alpha therapy seems like a stretch.</span></span></span></span></p></div>
</div>
</div>
</article>
</div>
</div>
</div>
</div>
<div
class="views-element-container nist-block no-print"
>
<h2
class="nist-block__title"
>Related posts</h2>
<div><div class="js-view-dom-id-561dde866112903bc727a6ca62db0d718ad1e62fb5177fe0f282403bb91c0cf6">
<div>
<article
about="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2025/01/23/ephraim_gau_tes_balloon_in_air_012125.JPG?itok=vkGGerAo" width="75" height="100" alt="A rectangular box coated with reflective foil hangs from cables over a parking lot." typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/high-flying-science-how-and-why-we-sent-refrigerator-halfway-space"><span>High-Flying Science: How and Why We Sent a Refrigerator Halfway to Space</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-02-12T12:00:00Z">February 12, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> NIST-developed tools can study the remnants of the Big Bang and more, and now researchers are working to launch these tools high above the Earth’s atmosphere —
</div>
</div>
</div>
</article>
</div>
<div>
<article
about="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2023/10/16/tara_fortier_working_in_lab_october_2023.jpg?itok=RkM9HePP" width="100" height="67" alt="A researcher wearing safety glasses reaches into a box of circuitry and other equipment, which emits a green glow. " typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/5-concepts-can-help-you-understand-quantum-mechanics-and-technology-without"><span>5 Concepts Can Help You Understand Quantum Mechanics and Technology — Without Math!</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-02-05T12:00:00Z">February 5, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> Quantum is everywhere, and you can understand the basic quirks of life at the quantum level … no math required.
</div>
</div>
</div>
</article>
</div>
<div>
<article
about="/blogs/taking-measure/robots-and-ai-are-working-together-bring-you-better-medicines-shampoo-and-more" class="nist-teaser"
>
<div class="nist-teaser__image">
<div class="entity-reference"> <a href="/blogs/taking-measure/robots-and-ai-are-working-together-bring-you-better-medicines-shampoo-and-more" hreflang="en"><img loading="lazy" src="/sites/default/files/styles/thumbnail/public/images/2024/12/18/peter_beaucage_afl_equipment_121024.jpg?itok=CdxapNjs" width="100" height="67" alt="Peter Beaucage wears safety glasses as he stands in the lab, holding a piece of equipment on display. " typeof="foaf:Image" />
</a>
</div>
</div>
<div class="nist-teaser__content-wrapper">
<header>
<h3 class="nist-teaser__title"><a href="/blogs/taking-measure/robots-and-ai-are-working-together-bring-you-better-medicines-shampoo-and-more"><span>Robots and AI Are Working Together to Bring You Better Medicines, Shampoo and More</span>
</a></h3>
<div class="nist-teaser__date">
<div class="daterange"><time datetime="2025-01-15T12:00:00Z">January 15, 2025</time>
</div>
</div>
</header>
<div class="nist-teaser__content">
<div class="text-with-summary"> Products you use every day are carefully formulated in a lab. Experts at NIST are now working to revolutionize how those products are made.
</div>
</div>
</div>
</article>
</div>
</div>
</div>
</div>
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Comments</h2>
<section>
<article data-comment-user-id="0" id="comment-98366" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Sharlene</span></span>
on
<span class="nist-comment__date">February 18, 2021 11:52 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1613667263"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-98366">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thank you for your work! Hoping my radiation therapy will be done before your research is complete, but really hoping that if I should have a recurrence in the future your work will be done and ready to go! It is so encouraging to know that there are scientists working on this area of treatment. There are so many of us that have needed it!</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98366">Reply</a></li></ul>
</div>
</article>
<div class="indented">
<article data-comment-user-id="0" id="comment-98371" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Denis Bergeron</span></span>
on
<span class="nist-comment__date">February 18, 2021 2:15 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1613675793"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/98366#comment-98366" class="permalink" rel="bookmark" hreflang="en">Thank you for your work! …</a></span>
</p>
<div class="nist-comment__permalink"><a href="#comment-98371">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thanks for writing, Sharlene, and best wishes for success with your therapy.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98371">Reply</a></li></ul>
</div>
</article>
</div>
<article data-comment-user-id="0" id="comment-98376" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">John</span></span>
on
<span class="nist-comment__date">February 18, 2021 2:51 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1639776307"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-98376">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thank you sincerely for your dedication and work. I have just been diagnosed with angiosarcoma, a more cellular rather then a tumor cancer. Your research sounds promising towards a novel treatment of this rare cancer. I&#039;m hopefully your success will lead to procedures that can save lives.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98376">Reply</a></li></ul>
</div>
</article>
<article data-comment-user-id="0" id="comment-98381" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">John</span></span>
on
<span class="nist-comment__date">February 18, 2021 3:02 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1613678644"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-98381">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thankyou, seriously, for your dedication and work. I have been diagnosed recently with angiosarcoma, a more cellular rather then tumor cancer. Your research looks promising in developing protocol and procedures in treating this type of cancer. Hopefully your research will someday provide hope to people experiencing this type of aggressive and terminal cancer. Keep up the dedication.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98381">Reply</a></li></ul>
</div>
</article>
<div class="indented">
<article data-comment-user-id="0" id="comment-98386" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Denis Bergeron</span></span>
on
<span class="nist-comment__date">February 18, 2021 3:16 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1613679456"></mark>
<span class="nist-comment__parent">| Replied to <a href="/comment/98381#comment-98381" class="permalink" rel="bookmark" hreflang="en">Thankyou, seriously, for…</a></span>
</p>
<div class="nist-comment__permalink"><a href="#comment-98386">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thanks, John. I can only share your hope that molecular targeting will lead to effective therapies for this type of cancer.</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98386">Reply</a></li></ul>
</div>
</article>
</div>
<article data-comment-user-id="0" id="comment-98391" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Ray Razavi</span></span>
on
<span class="nist-comment__date">February 19, 2021 10:54 AM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1639776317"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-98391">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thank you for your hard work, Denis! Brilliant scientists like you are the future of our country. Please know that we appreciate your hard work and dedication for making a better world for us!</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98391">Reply</a></li></ul>
</div>
</article>
<article data-comment-user-id="0" id="comment-98401" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Richard Mckeever</span></span>
on
<span class="nist-comment__date">February 19, 2021 10:54 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1613999619"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-98401">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>Thanks!</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/98401">Reply</a></li></ul>
</div>
</article>
<article data-comment-user-id="0" id="comment-104646" class="nist-comment js-comment">
<footer class="nist-comment__info">
<p class="submitted">
<span class="nist-comment__author"><span lang="" typeof="schema:Person" property="schema:name" datatype="">Denise F</span></span>
on
<span class="nist-comment__date">December 17, 2021 1:30 PM</span>
<mark class="hidden nist-comment__new" data-comment-timestamp="1639776284"></mark>
</p>
<div class="nist-comment__permalink"><a href="#comment-104646">Permalink</a></div>
</footer>
<div class="nist-comment__content">
<div class="text-long"><p>I did not directly benefit from your research, and I pray I don&#039;t have to, but your work will help many people immeasurably. Because of dedicated people just like yourself, that saw me through a battle with breast cancer, I was able to see my son graduate middle school and high school. He was able to have his mom hug him each time and everyday ever since. We thank you, immeasurably!</p>
</div>
<ul class="links inline nist-comment__links">
<li class="comment-reply nist-comment__link">
<a href="/comment/reply/node/1652361/comment_node_blog/104646">Reply</a></li></ul>
</div>
</article>
<h2>Add new comment</h2>
<link rel="stylesheet" media="all" href="/sites/default/files/css/css_Lx5yvw0vUi4TN7C0L-5Rdrp4Q049mXEKn-dXREWOtBs.css?delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxLzCvJTMov0U-E0Hpp-UW5OsmJBSXJGYn6SYnFqTppmTklqUX6KUWlBYk5ehAeAD47FNs&amp;exclude=eJx1UAuuwyAMuxAdR0IBsi5bIBWfdb39QrunVZOeRFDsWI7BQ3i4JnoW67-9u1fj_xlRkGxmkZnRQQbeGoVqfwmTqTZ3JeWirJkFomtFbSjPdoZjXKkhpaXIE-0vMSLsXLthQt0s7KG4JNFGquDVmCk_TN1qw6QJK-56O7N44HM_fazsDSFi-YNuXdez-oSHBF9tLLCx9AX48oHmSbhWu98XDdMZTV0gaWUr_tprgKaUBAJ2CSPByEbBMGzSm9PwQZ9XNisZg_Bh6O49LSrP_bCeBp4G_kZLFIqMH3oD_KWsjg" />
<form class="comment-comment-node-blog-form comment-form usa-form antibot" novalidate="novalidate" data-drupal-selector="comment-form" data-action="/comment/reply/node/1652361/comment_node_blog" action="/antibot" method="post" id="comment-form" accept-charset="UTF-8">
<noscript>
<div class="antibot-no-js antibot-message antibot-message-warning">You must have JavaScript enabled to use this form.</div>
</noscript>
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-name js-form-item-name">
<label for="edit-name" class="usa-label">
Your name
</label>
<input data-drupal-default-value="Anonymous" data-drupal-selector="edit-name" type="text" id="edit-name" name="name" value="" size="30" maxlength="60" class="form-text usa-input" />
</div>
<input data-drupal-selector="form-xyidjffcidw261y7jntpsaeprgvyzengvnyfppwvrf8" type="hidden" name="form_build_id" value="form-xYIdjFFCIdW261y7jnTPSaEpRGvYzENgvnyFPPWVrF8" class="usa-input" /><input data-drupal-selector="edit-comment-comment-node-blog-form" type="hidden" name="form_id" value="comment_comment_node_blog_form" class="usa-input" /><input data-drupal-selector="edit-antibot-key" type="hidden" name="antibot_key" value="" class="usa-input" /><div class="field--type-text-long field--name-comment-body field--widget-text-textarea js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-wrapper" id="edit-comment-body-wrapper"> <div class="js-text-format-wrapper js-form-item form-item">
<div class="form-item js-form-item form-type-textarea js-form-type-textarea form-item-comment-body-0-value js-form-item-comment-body-0-value">
<label for="edit-comment-body-0-value" class="usa-label form-required">
Comment
<span class="usa-label--required"> <span class="usa-sr-only">Required</span>*</span></label>
<div class="form-textarea-wrapper">
<textarea class="js-text-full text-full form-textarea required usa-textarea resize-vertical" data-entity_embed-host-entity-langcode="en" data-media-embed-host-entity-langcode="en" data-drupal-selector="edit-comment-body-0-value" id="edit-comment-body-0-value" name="comment_body[0][value]" rows="5" cols="60" placeholder="" required="required" aria-required="true"></textarea>
</div>
</div>
<div class="js-filter-wrapper filter-wrapper hidden js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-0-format" id="edit-comment-body-0-format"><div class="js-filter-guidelines filter-guidelines js-form-wrapper form-wrapper" data-drupal-selector="edit-comment-body-0-format-guidelines" id="edit-comment-body-0-format-guidelines"><div data-drupal-format-id="plain_text">
<h4>Plain text</h4>
<ul>
<li>No HTML tags allowed.</li>
<li>Web page addresses and email addresses turn into links automatically.</li>
<li>Lines and paragraphs break automatically.</li>
</ul>
</div>
</div>
</div>
</div>
</div>
<fieldset data-drupal-selector="edit-captcha" class="captcha captcha-type-challenge--image">
<legend class="captcha__title js-form-required form-required">
CAPTCHA
</legend>
<div class="captcha__element">
<input data-drupal-selector="edit-captcha-sid" type="hidden" name="captcha_sid" value="652142371" class="usa-input" /><input data-drupal-selector="edit-captcha-token" type="hidden" name="captcha_token" value="e08fnm03A8BXnrfZBCvUyvQeXdakwO8jRzIFXiwWBP8" class="usa-input" /><div class="captcha__image-wrapper js-form-wrapper form-wrapper" data-drupal-selector="edit-captcha-image-wrapper" id="edit-captcha-image-wrapper"><img data-drupal-selector="edit-captcha-image" src="/image-captcha-generate/652142371/1741077791" width="180" height="60" alt="Image CAPTCHA" title="Image CAPTCHA" loading="lazy" typeof="foaf:Image" />
</div>
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-captcha-response js-form-item-captcha-response">
<label for="edit-captcha-response" class="usa-label form-required">
What code is in the image?
<span class="usa-label--required"> <span class="usa-sr-only">Required</span>*</span></label>
<input autocomplete="off" data-drupal-selector="edit-captcha-response" aria-describedby="edit-captcha-response--description" type="text" id="edit-captcha-response" name="captcha_response" value="" size="15" maxlength="128" class="form-text required usa-input" required="required" aria-required="true" />
<div id="edit-captcha-response--description" class="description help-block">
Enter the characters shown in the image.
</div>
</div>
</div>
<div class="captcha__description description">This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.</div>
</fieldset>
<div data-drupal-selector="edit-actions" class="form-actions js-form-wrapper form-wrapper" id="edit-actions--2"><input data-drupal-selector="edit-submit" type="submit" id="edit-submit" name="op" value="Save" class="button button--primary js-form-submit form-submit usa-button" /></div>
<div class="comments__disclaimer padding-top-2">
<em>Please be respectful when posting comments. We will post all comments without editing as long as they are appropriate for a public, family friendly website, are on topic and do not contain profanity, personal attacks, misleading or false information/accusations or promote specific commercial products, services or organizations. Comments that violate our comment policy or include links to non-government organizations/web pages will not be posted.</em>
</div>
</form>
</section>
</div>
</div>
<aside class="nist-page__region nist-page__region--sidebar-second tablet-lg:grid-col-4">
<div>
<div
class="nist-block"
>
<div>
<div about="/blogs/taking-measure">
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Our Science in Your Inbox</h2>
<div class="text-long"><p>Subscribe to our weekly emails.</p>
<form action="https://public.govdelivery.com/accounts/USNIST/subscribers/qualify" accept-charset="UTF-8" method="post">
<input name="utf8" type="hidden" value="&#x2713;">
<input type="hidden" name="authenticity_token" value="GleKn0r3EFkuIRsIWsyLN6Mrqim4qc3U7eIUCWGqBFz2ziQ/qv0gnQTJUhVbKHMSlmrsC7UHIm6S8IfK6qk9EQ==">
<input type="hidden" name="topic_id" id="topic_id" value="USNIST_309">
<div class="grid-row grid-gap-1">
<div class="tablet:grid-col-8">
<label class="usa-sr-only" for="email">Enter Email Address</label>
<input class="usa-input" type="text" name="email" id="email" title="email" placeholder="Your Email Address">
</div>
<div class="tablet:grid-col-4">
<input type="submit" name="commit" value="Sign Up" class="usa-button margin-top-1">
</div>
</div>
</form>
</div>
</div>
<div
class="views-exposed-form usa-form filters nist-block" novalidate="novalidate" data-drupal-selector="views-exposed-form-search-blog-taking-measure-search-page"
>
<h2
class="nist-block__title"
>Search</h2>
<form action="/blogs/taking-measure/search" method="get" id="views-exposed-form-search-blog-taking-measure-search-page" accept-charset="UTF-8" class="usa-form">
<div class="form-item js-form-item form-type-textfield js-form-type-textfield form-item-k js-form-item-k form-no-label">
<input placeholder="Search this blog" data-drupal-selector="edit-k" type="text" id="edit-k" name="k" value="" size="30" maxlength="128" class="form-text usa-input" />
<div id="edit-k--description" class="description help-block">
Put exact phrase in quotes (e.g., "artificial intelligence")
</div>
</div>
<div class="grid-col-12 form-actions js-form-wrapper form-wrapper" data-drupal-selector="edit-actions" id="edit-actions"><input data-drupal-selector="edit-submit-search-blog" type="submit" id="edit-submit-search-blog" value="Search" class="button js-form-submit form-submit usa-button" /></div>
</form>
</div>
<div
class="nist-block no-print"
>
<h2
class="nist-block__title"
>Stay connected</h2>
<div><a href="https://www.facebook.com/nist" class="nist-social nist-social--facebook" title="Facebook" ><span>Facebook</span></a><a href="https://www.linkedin.com/company/nist" class="nist-social nist-social--linkedin" title="LinkedIn" ><span>LinkedIn</span></a><a href="https://www.x.com/nist" class="nist-social nist-social--x" title="X (Twitter)" ><span>X (Twitter)</span></a><a href="https://www.youtube.com/nist" class="nist-social nist-social--youtube" title="Youtube" ><span>Youtube</span></a><a href="https://www.instagram.com/nist/" class="nist-social nist-social--instagram" title="Instagram" ><span>Instagram</span></a><a href="https://public.govdelivery.com/accounts/USNIST/subscriber/new?topic_id=USNIST_309" class="nist-social nist-social--envelope" title="GovDelivery" ><span>GovDelivery</span></a></div>
</div>
<div
class="views-element-container nist-block"
>
<h2
class="nist-block__title"
>Categories</h2>
<div><div class="js-view-dom-id-b54b123cac39f02e192b26d48179b63fe2f3d0a307943dbf68c260b3b9fdd5db">
<div>
<select class="usa-select ViewsJumpMenu js-viewsJumpMenu" title="-- Choose --" id="blog-categories-takingm-jump-menu">
<option>-- Choose --</option>
<option data-url="/blogs/taking-measure/categories/249466">Advanced communications</option>
<option data-url="/blogs/taking-measure/categories/248321">Bioscience</option>
<option data-url="/blogs/taking-measure/categories/248371">Buildings and Construction</option>
<option data-url="/blogs/taking-measure/categories/248416">Chemistry</option>
<option data-url="/blogs/taking-measure/categories/248486">Electronics</option>
<option data-url="/blogs/taking-measure/categories/248531">Energy</option>
<option data-url="/blogs/taking-measure/categories/248561">Environment</option>
<option data-url="/blogs/taking-measure/categories/248586">Fire</option>
<option data-url="/blogs/taking-measure/categories/248616">Forensic Science</option>
<option data-url="/blogs/taking-measure/categories/248651">Health</option>
<option data-url="/blogs/taking-measure/categories/249421">Information technology</option>
<option data-url="/blogs/taking-measure/categories/2748236">Infrastructure</option>
<option data-url="/blogs/taking-measure/categories/248866">Manufacturing</option>
<option data-url="/blogs/taking-measure/categories/248946">Materials</option>
<option data-url="/blogs/taking-measure/categories/249011">Mathematics and statistics</option>
<option data-url="/blogs/taking-measure/categories/249051">Metrology</option>
<option data-url="/blogs/taking-measure/categories/249126">Nanotechnology</option>
<option data-url="/blogs/taking-measure/categories/249451">Neutron research</option>
<option data-url="/blogs/taking-measure/categories/249426">Performance excellence</option>
<option data-url="/blogs/taking-measure/categories/249241">Physics</option>
<option data-url="/blogs/taking-measure/categories/249461">Public safety</option>
<option data-url="/blogs/taking-measure/categories/249456">Resilience</option>
<option data-url="/blogs/taking-measure/categories/249341">Standards</option>
<option data-url="/blogs/taking-measure/categories/2813456">Technology transfer</option>
<option data-url="/blogs/taking-measure/categories/249396">Transportation</option>
</select>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</aside>
</div>
</div>
<div class="grid-container">
</div>
</section>
</div>
<div data-elastic-exclude>
<!-- nist-index-ignore-start -->
<footer class="nist-footer padding-bottom-4">
<div class="grid-container nist-footer__info">
<div class="grid-row">
<div class="tablet:grid-col-6">
<div class="nist-footer__logo">
<a href="/" title="National Institute of Standards and Technology" rel="home">
<img class="nist-footer__logo-img" src="/libraries/nist-component-library/dist/img/logo/NIST-Logo-Brand-White.svg" alt="National Institute of Standards and Technology logo" width="300px" height="42px" />
</a>
</div>
<div class="nist-footer__contact">
<h3 class="nist-footer__contact-heading">HEADQUARTERS</h3>
<address>
100 Bureau Drive<br>
Gaithersburg, MD 20899<br>
<a href="tel:301-975-2000">301-975-2000</a>
</address>
<p>
<a href="mailto:do-webmaster@nist.gov">Webmaster</a> | <a href="https://www.nist.gov/about-nist/contact-us">Contact Us</a> | <a href="https://www.nist.gov/visit">Our Other Offices</a>
</p>
</div>
</div>
<div class="tablet:grid-col-6">
<div class="nist-footer__social-links">
<a class="nist-social nist-social--x-white" href=" https://x.com/NIST">
<span>X.com</span>
</a>
<a class="nist-social nist-social--facebook-white" href=" https://www.facebook.com/NIST">
<span>Facebook</span>
</a>
<a class="nist-social nist-social--linkedin-white" href=" https://www.linkedin.com/company/nist">
<span>LinkedIn</span>
</a>
<a class="nist-social nist-social--instagram-white" href=" https://www.instagram.com/nist/">
<span>Instagram</span>
</a>
<a class="nist-social nist-social--youtube-white" href=" https://www.youtube.com/NIST">
<span>YouTube</span>
</a>
<a class="nist-social nist-social--giphy-white" href=" https://giphy.com/nist">
<span>Giphy</span>
</a>
<a class="nist-social nist-social--rss-white" href=" https://www.nist.gov/news-events/nist-rss-feeds">
<span>RSS Feed</span>
</a>
<a class="nist-social nist-social--envelope-white" href=" https://public.govdelivery.com/accounts/USNIST/subscriber/new">
<span>Mailing List</span>
</a>
</div>
<div class="nist-footer__feedback">
How are we doing? <a class="usa-button" rel="nofollow" href="/form/nist-gov-feedback?destination=/blogs/taking-measure/nist-radioactivity-measurements-get-ball-rolling-new-cancer-therapies" title="Provide feedback">Feedback</a>
</div>
</div>
</div>
</div>
<div class="grid-container">
<div class="nist-footer__nav" role="navigation">
<ul>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/privacy-policy">Site Privacy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/oism/accessibility">Accessibility</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/privacy">Privacy Program</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/oism/copyrights">Copyrights</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.commerce.gov/vulnerability-disclosure-policy">Vulnerability Disclosure</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/no-fear-act-policy">No Fear Act Policy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/office-director/freedom-information-act">FOIA</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/environmental-policy-statement">Environmental Policy</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/summary-report-scientific-integrity">Scientific Integrity</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.nist.gov/nist-information-quality-standards">Information Quality Standards</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://www.commerce.gov/">Commerce.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="http://www.science.gov/">Science.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="http://www.usa.gov/">USA.gov</a>
</li>
<li class="nist-footer__menu-item">
<a href="https://vote.gov/">Vote.gov</a>
</li>
</ul>
</div>
</div>
</footer>
<!-- nist-index-ignore-end -->
</div>
</div>
<script type="application/json" data-drupal-selector="drupal-settings-json">{"path":{"baseUrl":"\/","pathPrefix":"","currentPath":"node\/1652361","currentPathIsAdmin":false,"isFront":false,"currentLanguage":"en"},"pluralDelimiter":"\u0003","suppressDeprecationErrors":true,"back_to_top":{"back_to_top_button_trigger":100,"back_to_top_speed":1200,"back_to_top_prevent_on_mobile":false,"back_to_top_prevent_in_admin":true,"back_to_top_button_type":"image","back_to_top_button_text":"Back to top"},"google_analytics":{"account":"G-HEQ0YF2VYL","trackOutbound":true,"trackMailto":true,"trackTel":true,"trackDownload":true,"trackDownloadExtensions":"7z|aac|arc|arj|asf|asx|avi|bin|bsh|c|csv|doc(x|m)?|dot(x|m)?|dw(fx|g|gd)|dxf|eps|epub|exe|f(90)|flv|gif|gz|gzip|hqx|jar|jpe?g|js|m1v|mp(2|3|4|e?g)|mobi|mov(ie)?|msi|msp|pdf|phps|pl|png|ppt(x|m)?|pot(x|m)?|pps(x|m)?|ppam|sld(x|m)?|thmx|qtm?|ra(m|r)?|rfa|rtf|rvt|sch|sea|sit|swf|tar|tgz|tif|txt|txz|wav|wma|wmv|wpd|wrl|xls(x|m|b)?|xlt(x|m)|xlam|xml|xsd|z|zip"},"nist_search":{"clickTracking":"search-report-click","isDebug":false,"clickTrackEnabled":true,"message":"NIST Search in debug mode. Check the browsers network inspector for Click Track reporting results..."},"data":{"extlink":{"extTarget":false,"extTargetNoOverride":false,"extNofollow":false,"extNoreferrer":false,"extFollowNoOverride":false,"extClass":"ext","extLabel":"(link is external)","extImgClass":false,"extSubdomains":true,"extExclude":"\\.gov\\\/|\\.mil\\\/|\\manufacturingusa\\.com\\\/","extInclude":"","extCssExclude":".ck-editor, .nist-video-thumbnail__lightbox-trigger, a.nist-icon--mail-blue","extCssExplicit":"","extAlert":true,"extAlertText":"Thank you for visiting NIST. We hope your visit was informative. We have provided a link to this site because it has information that may be of interest to our users. NIST does not necessarily endorse the views expressed or the facts presented on this site. Further, NIST does not endorse any commercial products that may be advertised or available on this site. Click OK to be directed to your link.","mailtoClass":"0","mailtoLabel":"(link sends email)","extUseFontAwesome":false,"extIconPlacement":"after","extFaLinkClasses":"fa fa-external-link","extFaMailtoClasses":"fa fa-envelope-o","whitelistedDomains":[]}},"viewsJumpMenu":{"blog-categories-takingm-jump-menu":{"new_window":false}},"ajaxTrustedUrl":{"\/blogs\/taking-measure\/search":true,"\/comment\/reply\/node\/1652361\/comment_node_blog":true},"user":{"uid":0,"permissionsHash":"bd6a443844dbe99b4e6942f3b1397526e760137efd2b1ee6b2d588fc414dff20"},"antibot":{"forms":{"comment-form":{"id":"comment-form","key":"8s3HerPNUiBWAup-NU0eICdfN5XSJ1VRGAW7gyEytXD"}}}}</script>
<script src="/sites/default/files/js/js_jDaFaXhHm6gPUKstNYX9eIyoQXghVs3g7rbR0QoqpYY.js?scope=footer&amp;delta=0&amp;language=en&amp;theme=nist_www&amp;include=eJxdkAuOwyAMRC8E9ZGQCQ51CzgCp2lvX8hHu6qEBG8Yz0j2OD2dSj8L-L-3ezQTRWIihwXTR3lq8CuYwk3dzF0LspUkGJzWHsIlQsTju7ES56XKi-BXGC27pnfK1HsleawuS4DADX0PTlyeuwdiEo_JniNwJwxUL3Tbtv1z0FvHIIS6LphuJ5pJcqail3yi9R_7YtqoHskZY-GZJzPE5h5rXlz3rbCzHWwHGyzKXhTO-zZLzaavQ6leFQd9AQAFjIc"></script>
<script src="https://siteimproveanalytics.com/js/siteanalyze_6017546.js" async></script>
<script src="/sites/default/files/js/js_phYs2jDctfdGpas0b2o3STtb7Y4B0bPDz-8rro3OgSg.js?scope=footer&amp;delta=2&amp;language=en&amp;theme=nist_www&amp;include=eJxdkAuOwyAMRC8E9ZGQCQ51CzgCp2lvX8hHu6qEBG8Yz0j2OD2dSj8L-L-3ezQTRWIihwXTR3lq8CuYwk3dzF0LspUkGJzWHsIlQsTju7ES56XKi-BXGC27pnfK1HsleawuS4DADX0PTlyeuwdiEo_JniNwJwxUL3Tbtv1z0FvHIIS6LphuJ5pJcqail3yi9R_7YtqoHskZY-GZJzPE5h5rXlz3rbCzHWwHGyzKXhTO-zZLzaavQ6leFQd9AQAFjIc"></script>
<script type="text/javascript">window.NREUM||(NREUM={});NREUM.info={"beacon":"bam.nr-data.net","licenseKey":"37b7ccb661","applicationID":"1089704227","transactionName":"YFxUN0sADEdYVkBaClkWdwBNCA1aFnFGRhVWVWoNVgUHaHpaWkcXWFVaBks9LFtdUGJaAEB6WQ1NEw1YVVBGHltBUFMU","queueTime":5,"applicationTime":1443,"atts":"TBtXQQMaH0k=","errorBeacon":"bam.nr-data.net","agent":""}</script></body>
</html>
Reference in a new issue View git blame Copy permalink