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Heat in U.S. Prisons and Jails
This white paper addresses three important but largely neglected questions: • How will increased temperatures and heat waves caused by climate change affect prisons, jails, and their staff and inmate populations? • What can correctional departments do to prepare for greater heat and minimize the dangers it poses? • What are the legal implications of excessive heat in prisons and jails
Three dimensional generalization of the - Heisenberg model on a square lattice and role of the interlayer coupling
A possibility to describe magnetism in the iron pnictide parent compounds in
terms of the two-dimensional frustrated Heisenberg - model has been
actively discussed recently. However, recent neutron scattering data has shown
that the pnictides have a relatively large spin wave dispersion in the
direction perpendicular to the planes. This indicates that the third dimension
is very important. Motivated by this observation we study the --
model that is the three dimensional generalization of the -
Heisenberg model for and S = 1. Using self-consistent spin wave
theory we present a detailed description of the staggered magnetization and
magnetic excitations in the collinear state. We find that the introduction of
the interlayer coupling suppresses the quantum fluctuations and
strengthens the long range ordering. In the -- model, we find
two qualitatively distinct scenarios for how the collinear phase becomes
unstable upon increasing . Either the magnetization or one of the spin
wave velocities vanishes. For renormalization due to quantum
fluctuations is significantly stronger than for S=1, in particular close to the
quantum phase transition. Our findings for the -- model are of
general theoretical interest, however, the results show that it is unlikely
that the model is relevant to undoped pnictides.Comment: 11 pages, 10 figures. Updated version, several references adde
Performance assessment of a NaI(Tl) gamma counter for PET applications with methods for improved quantitative accuracy and greater standardization
BACKGROUND: Although NaI(Tl) gamma counters play an important role in many quantitative positron emission tomography (PET) protocols, their calibration for positron-emitting samples has not been standardized across imaging sites. In this study, we characterized the operational range of a gamma counter specifically for positron-emitting radionuclides, and we assessed the role of traceable (68)Ge/(68)Ga sources for standardizing system calibration. METHODS: A NaI(Tl) gamma counter was characterized with respect to count rate performance, adequacy of detector shielding, system stability, and sample volume effects using positron-emitting radionuclides (409- to 613-keV energy window). System efficiency was measured using (18)F and compared with corresponding data obtained using a long-lived (68)Ge/(68)Ga source that was implicitly traceable to a national standard. RESULTS: One percent count loss was measured at 450 × 10(3) counts per minute. Penetration of the detector shielding by 511-keV photons gave rise to a negligible background count rate. System stability tests showed a coefficient of variation of 0.13% over 100 days. For a sample volume of 4 mL, the efficiencies relative to those at 0.1 mL were 0.96, 0.94, 0.91, 0.78, and 0.72 for (11)C, (18)F, (125)I, (99m)Tc, and (51)Cr, respectively. The efficiency of a traceable (68)Ge/(68)Ga source was 30.1% ± 0.07% and was found to be in close agreement with the efficiency for (18)F after consideration of the different positron fractions. CONCLUSIONS: Long-lived (68)Ge/(68)Ga reference sources, implicitly traceable to a national metrology institute, can aid standardization of gamma counter calibration for (18)F. A characteristic feature of positron emitters meant that accurate calibration could be maintained over a wide range of sample volumes by using a narrow energy window centered on the 511-keV peak
Estimating Risk from Ambient Concentrations of Acrolein across the United States
BACKGROUND: Estimated ambient concentrations of acrolein, a hazardous air pollutant, are greater than the U.S. Environmental Protection Agency (EPA) reference concentration throughout the United States, making it a concern for human health. However, there is no method for assessing the extent of risk under the U.S. EPA noncancer risk assessment framework. OBJECTIVES: We estimated excess risks from ambient concentrations of acrolein based on dose–response modeling of a study in rats with a relationship between acrolein and residual volume/total lung capacity ratio (RV/TLC) and specific compliance (sC(L)), markers for altered lung function. METHODS: Based on existing literature, we defined values above the 90th percentile for controls as “adverse.” We estimated the increase over baseline response that would occur in the human population from estimated ambient concentrations of acrolein, taken from the U.S. EPA’s National-Scale Air Toxics Assessment for 1999, after standard animal-to-human conversions and extrapolating to doses below the experimental data. RESULTS: The estimated median additional number of adverse sC(L) outcomes across the United States was approximately 2.5 cases per 1,000 people. The estimated range of additional outcomes from the 5th to the 95th percentile of acrolein concentration levels across census tracts was 0.28–14 cases per 1,000. For RV/TLC, the median additional outcome was 0.002 per 1,000, and the additional outcome at the 95th percentile was 0.13 per 1,000. CONCLUSIONS: Although there are uncertainties in estimating human risks from animal data, this analysis demonstrates a method for estimating health risks for noncancer effects and suggests that acrolein could be associated with decreased respiratory function in the United States
The Douglas-Fir Genome Sequence Reveals Specialization of the Photosynthetic Apparatus in Pinaceae.
A reference genome sequence for Pseudotsuga menziesii var. menziesii (Mirb.) Franco (Coastal Douglas-fir) is reported, thus providing a reference sequence for a third genus of the family Pinaceae. The contiguity and quality of the genome assembly far exceeds that of other conifer reference genome sequences (contig N50 = 44,136 bp and scaffold N50 = 340,704 bp). Incremental improvements in sequencing and assembly technologies are in part responsible for the higher quality reference genome, but it may also be due to a slightly lower exact repeat content in Douglas-fir vs. pine and spruce. Comparative genome annotation with angiosperm species reveals gene-family expansion and contraction in Douglas-fir and other conifers which may account for some of the major morphological and physiological differences between the two major plant groups. Notable differences in the size of the NDH-complex gene family and genes underlying the functional basis of shade tolerance/intolerance were observed. This reference genome sequence not only provides an important resource for Douglas-fir breeders and geneticists but also sheds additional light on the evolutionary processes that have led to the divergence of modern angiosperms from the more ancient gymnosperms
Negative Effect of Smoking on the Performance of the QuantiFERON TB Gold in Tube Test.
False negative and indeterminate Interferon Gamma Release Assay (IGRA) results are a well documented problem. Cigarette smoking is known to increase the risk of tuberculosis (TB) and to impair Interferon-gamma (IFN-γ) responses to antigenic challenge, but the impact of smoking on IGRA performance is not known. The aim of this study was to evaluate the effect of smoking on IGRA performance in TB patients in a low and high TB prevalence setting respectively. Patients with confirmed TB from Denmark (DK, n = 34; 20 smokers) and Tanzania (TZ, n = 172; 23 smokers) were tested with the QuantiFERON-TB Gold In tube (QFT). Median IFN-γ level in smokers and non smokers were compared and smoking was analysed as a risk factor for false negative and indeterminate QFT results. Smokers from both DK and TZ had lower IFN-γ antigen responses (median 0.9 vs. 4.2 IU/ml, p = 0.04 and 0.4 vs. 1.6, p < 0.01), less positive (50 vs. 86%, p = 0.03 and 48 vs. 75%, p < 0.01) and more false negative (45 vs. 0%, p < 0.01 and 26 vs. 11%, p = 0.04) QFT results. In Tanzanian patients, logistic regression analysis adjusted for sex, age, HIV and alcohol consumption showed an association of smoking with false negative (OR 17.1, CI: 3.0-99.1, p < 0.01) and indeterminate QFT results (OR 5.1, CI: 1.2-21.3, p = 0.02). Cigarette smoking was associated with false negative and indeterminate IGRA results in both a high and a low TB endemic setting independent of HIV status
Bostonia: The Boston University Alumni Magazine. Volume 9
Founded in 1900, Bostonia magazine is Boston University's main alumni publication, which covers alumni and student life, as well as university activities, events, and programs
Social preferences, accountability, and wage bargaining
We assess the extent of preferences for employment in a collective wage bargaining situation with heterogeneous workers. We vary the size of the union and introduce a treatment mechanism transforming the voting game into an individual allocation task. Our results show that highly productive workers do not take employment of low productive workers into account when making wage proposals, regardless of whether insiders determine the wage or all workers. The level of pro-social preferences is small in the voting game, while it increases as the game is transformed into an individual allocation task. We interpret this as an accountability effect
Scaling of the F_2 structure function in nuclei and quark distributions at x>1
We present new data on electron scattering from a range of nuclei taken in
Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the
cross section for , which is sensitive to short range contributions to the
nuclear wave-function, and in deep inelastic scattering corresponds to probing
extremely high momentum quarks. This result agrees with higher energy muon
scattering measurements, but is in sharp contrast to neutrino scattering
measurements which suggested a dramatic enhancement in the distribution of the
`super-fast' quarks probed at x>1. The falloff at x>1 is noticeably stronger in
^2H and ^3He, but nearly identical for all heavier nuclei.Comment: 5 pages, 4 figures, to be submitted to physical revie
New measurements of high-momentum nucleons and short-range structures in nuclei
We present new measurements of electron scattering from high-momentum
nucleons in nuclei. These data allow an improved determination of the strength
of two-nucleon correlations for several nuclei, including light nuclei where
clustering effects can, for the first time, be examined. The data also include
the kinematic region where three-nucleon correlations are expected to dominate.Comment: 5 pages, 3 figures. Results from JLab E02-01
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