Updated Nucleosynthesis Constraints on Unstable Relic Particles

We revisit the upper limits on the abundance of unstable massive relic particles provided by the success of Big-Bang Nucleosynthesis calculations. We use the cosmic microwave background data to constrain the baryon-to-photon ratio, and incorporate an extensively updated compilation of cross sections into a new calculation of the network of reactions induced by electromagnetic showers that create and destroy the light elements deuterium, he3, he4, li6 and li7. We derive analytic approximations that complement and check the full numerical calculations. Considerations of the abundances of he4 and li6 exclude exceptional regions of parameter space that would otherwise have been permitted by deuterium alone. We illustrate our results by applying them to massive gravitinos. If they weigh ~100 GeV, their primordial abundance should have been below about 10^{-13} of the total entropy. This would imply an upper limit on the reheating temperature of a few times 10^7 GeV, which could be a potential difficulty for some models of inflation. We discuss possible ways of evading this problem.Comment: 40 pages LaTeX, 18 eps figure

Muon fluence measurements at the site boundary for 1985

Muon fluence (muons cm/sup -2/) was measured downstream of the experimental area beamlines, just beyond the Fermilab site boundary at Route 38. The purpose of these measurements was to obtain an estimate of the yearly off-site radiation exposure to the general population due to accelerator-produced muons during the 1985 800 GeV run

Personal dosimetry in a mixed field of high energy muons and neutrons

High energy accelerators quite often emit muons. These particles behave in matter as would heavy electrons and are thus difficult to attenuate with shielding in many situations. Hence, these muons can be a source of radiation exposure to personnel and suitable methods of measuring the absorbed dose received to these people is obviously required. In practical situations, such muon radiation fields are often mixed with neutrons, well-known to be an even more troublesome particle species with respect to dosimetry. In this paper, we report on fluence measurements made in such a mixed radiation field and a comparison of dosimeter responses. We conclude that commercial self-reading dosimeters and film badges provided an adequate measure of the absorbed dose due to muons

Muon fluence measurements at 800 GeV

Muon fluence (muons-cm/sup -2/) was measured downstream of enclosure PW8 at three locations along the extension of the PW beamline during the 1984 800-GeV accelerator run. The main goal of these measurements was to determine muon dose-equivalent at various Fermilab locations, and to obtain an estimate of the yearly off-site radiation exposure to the general population due to accelerator-produced muons. The contribution from the PW beamline was investigated because the targeted primary proton beam intensity was consistently higher than for other beamlines. More extensive but similar measurements have been reported by Cossairt for 350 and 400 GeV operation

GEOMETRICAL CONSIDERATIONS IN THE MEASUREMENT OF THE RATIO L/R IN THE SCATTERING OF POLARIZED NUCLEONS

A FORTRAN II program is described which is used to evaluate the effect of a spatially extended analyzer and detector on the measurement of the left- right asymmetry in the scattering of polarized particles. The initial scatterer is assumed to be a point source and the analyzer, second scatterer, and detector are treated as planes whose dimensions are adjustable as input data in the program. The calculation allows for any glven angular distribution of particle flux from the source if this distribution can be represented as a finite power series in the cosine of the angle of emission. A similar representation is used to describe the scattering properties of the analyzer. The integrals over the finite dimensions of the analyzer and detector are evaluated by a standard Newton- Cotes quadrature approximation for multidimensional integration. A discussion of this approximation as well as a listing of the FORTRAN program are included. (auth

Routine patient-reported experience measurement of shared decision-making in the USA: a qualitative study of the current state according to frontrunners

Contains fulltext : 221003.pdf (publisher's version ) (Open Access)OBJECTIVES: To identify and describe instances of routine patient-reported shared decision-making (SDM) measurement in the USA, and to explore barriers and facilitators of routine patient-reported SDM measurement for quality improvement. SETTING: Payer and provider healthcare organisations in the USA. PARTICIPANTS: Current or former adult employees of healthcare organisations with prior SDM activity and that may be conducting routine SDM measurement (n=21). OUTCOMES: Qualitative interview and survey data collected through snowball sampling recruitment strategy to inform barriers and facilitators of routine patient-reported SDM measurement. RESULTS: Three participating sites routinely measured SDM from patients' perspectives, including one payer organisation and two provider organisations-with the largest measurement effort taking place in the payer organisation. Facilitators of SDM measurement included SDM as a core organisational value or strategic priority, trialability of SDM measurement programmes, flexibility in how measures can be administered and existing momentum from payer-mandated measurement programmes. Barriers included competing organisational priorities with regard to patient-reported measurement and lack of perceived comparative advantage of patient-reported SDM measurement. CONCLUSIONS: Payers have a unique opportunity to encourage emphasis on SDM within healthcare organisations, including routine patient-reported measurement of SDM; however, provider organisations are currently best placed to make effective use of this type of data

Cycling as a novel approach to resistance training increases muscle strength, power, and selected functional abilities in healthy older women

OBJECTIVES: Observer OPTION(5) was designed as a more efficient version of OPTION(12), the most commonly used measure of shared decision making (SDM). The current paper assesses the psychometric properties of OPTION(5). METHODS: Two raters used OPTION(5) to rate recordings of clinical encounters from two previous patient decision aid (PDA) trials (n=201; n=110). A subsample was re-rated two weeks later. We assessed discriminative validity, inter-rater reliability, intra-rater reliability, and concurrent validity. RESULTS: OPTION(5) demonstrated discriminative validity, with increases in SDM between usual care and PDA arms. OPTION(5) also demonstrated concurrent validity with OPTION(12), r=0.61 (95%CI 0.54, 0.68) and intra-rater reliability, r=0.93 (0.83, 0.97). The mean difference in rater score was 8.89 (95% Credibility Interval, 7.5, 10.3), with intraclass correlation (ICC) of 0.67 (95% Credibility Interval, 0.51, 0.91) for the accuracy of rater scores and 0.70 (95% Credibility Interval, 0.56, 0.94) for the consistency of rater scores across encounters, indicating good inter-rater reliability. Raters reported lower cognitive burden when using OPTION(5) compared to OPTION(12). CONCLUSIONS: OPTION(5) is a brief, theoretically grounded observer measure of SDM with promising psychometric properties in this sample and low burden on raters. PRACTICE IMPLICATIONS: OPTION(5) has potential to provide reliable, valid assessment of SDM in clinical encounters

Comparing the impact of an icon array versus a bar graph on preference and understanding of risk information: Results from an online, randomized study.

Few studies have examined the best way to convey the probability of serious events occurring in the future (i.e., risk of stroke or death) to persons with low numeracy or graph literacy proficiency. To address this gap, we developed and user-tested a bar graph and compared it to icon arrays to assess its impact on understanding and preference for viewing risk information. To determine the: (i) formats' impact on participants' understanding of risk information; (ii) formats' impact on understanding and format preference across numeracy and graph literacy subgroups; (iii) rationale supporting participants' preference for each graphical display format. An online sample (evenly made up of participants with high and low objective numeracy and graph literacy) was randomized to view either the icon array or the bar graph. Each format conveyed the risk of major stroke and death five years after choosing surgery, a stent, or medication to treat carotid artery stenosis. Participants answered questions to assess their understanding of the risk information. Lastly, both formats were presented in parallel, and participants were asked to identify their preferred format to view risk information and explain their preference. Of the 407 participants, 197 were assigned the icon array and 210 the bar graph. Understanding of risk information and format preference did not differ significantly between the two trial arms, irrespective of numeracy and graph literacy proficiency. High numeracy and graph literacy proficiency was associated with high understanding (p<0.01) and a preference for the bar graph (p = 0.01). We found no evidence to demonstrate the superiority of one format over another on understanding. The majority of participants preferred viewing the risk information using the bar graph format