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Despite a number of compelling entrapment claims in post-9/11 US terrorism cases, these claims have nearly always failed. While previous research suggests possible reasons for this almost complete failure of the entrapment defense, no research has yet systematically examined the mechanisms responsible for this result. Drawing on thirty-seven interviews with individuals with in-depth knowledge of particular cases, as well as textual analysis of court decisions and quantitative analysis of a terrorism database, this article identifies several factors contributing to the entrapment defense’s failure. These include strategic choices by defendants to plead guilty or use other defenses, prosecutorial misconduct, evidence manipulation by informants and police, deficient entrapment doctrines, and procedural irregularities. Consistent with the general trend of counterterrorism law enhancing government power while reducing accountability, the multiple opportunities for authorities to manipulate the legal process leave defendants with little realistic chance of acquittal on entrapment grounds.
Growth in early life is associated with various individual health outcomes in adulthood, but limited research has been done on associations with a more comprehensive measure of health. Combining information from multiple biological systems, allostatic load (AL) provides such a quantitative measure of overall physiological health. We used longitudinal data from the Birth to Twenty Plus cohort in South Africa to calculate an AL score at age 22 years and examined associations with birth weight and linear growth and weight gain from age 0 to 2 years and 2 to 5 years, as attenuated by trajectories of body mass index and pubertal development in later childhood and adolescence. Differences in total AL score between males and females were small, though levels of individual biological factors contributing to AL differed by sex. Increased weight gain from age 2 to 5 years among males was associated with an increased risk of high AL, but no other early-life measures were associated with AL. Increased adiposity through childhood and adolescence in females was associated with higher AL in early adulthood. These results illustrate that patterns of early-life growth are not consistently associated with higher AL. While more research is needed to link AL in young adulthood to later health outcomes, these results also suggest increased adiposity during childhood and adolescence represents a potential early sign of later physiological risk.
We have observed the G23 field of the Galaxy AndMass Assembly (GAMA) survey using the Australian Square Kilometre Array Pathfinder (ASKAP) in its commissioning phase to validate the performance of the telescope and to characterise the detected galaxy populations. This observation covers ~48 deg2 with synthesised beam of 32.7 arcsec by 17.8 arcsec at 936MHz, and ~39 deg2 with synthesised beam of 15.8 arcsec by 12.0 arcsec at 1320MHz. At both frequencies, the root-mean-square (r.m.s.) noise is ~0.1 mJy/beam. We combine these radio observations with the GAMA galaxy data, which includes spectroscopy of galaxies that are i-band selected with a magnitude limit of 19.2. Wide-field Infrared Survey Explorer (WISE) infrared (IR) photometry is used to determine which galaxies host an active galactic nucleus (AGN). In properties including source counts, mass distributions, and IR versus radio luminosity relation, the ASKAP-detected radio sources behave as expected. Radio galaxies have higher stellar mass and luminosity in IR, optical, and UV than other galaxies. We apply optical and IR AGN diagnostics and find that they disagree for ~30% of the galaxies in our sample. We suggest possible causes for the disagreement. Some cases can be explained by optical extinction of the AGN, but for more than half of the cases we do not find a clear explanation. Radio sources aremore likely (~6%) to have an AGN than radio quiet galaxies (~1%), but the majority of AGN are not detected in radio at this sensitivity.
Carbon-14 (radiocarbon, 14C) is an important radionuclide in the inventory of radioactive waste in many disposal programs due to its significant dose contributions in safety assessments for geological repositories. Activated steels from nuclear reactors are one of the major sources of 14C. Knowledge of 14C release from steel wastes and its chemical form (speciation) is limited giving rise to uncertainty regarding the fate of 14C and a conservative treatment in assessment calculations. In this work, we summarize and make a synthesis of selected results from Work Package 2 of the EU CAST project aiming to improve understanding of 14C release related to steel corrosion under repository-relevant conditions. The outcome of the experiments is discussed in the context of the long-term evolution of a repository and its potential consequences for safety assessment.
The radiocarbon (14C) content of irradiated graphite is the most important problem for the management of Spanish irradiated graphite (Vandellós I NPP) as L&ILW, due to this material exceeding the maximum 14C inventory for the C.A. El Cabril repository. Therefore, the encapsulation of graphite in an impermeable matrix and making an appropriate waste form are indicated as potential management options to be studied. The conversion of the graphite to a long-term stable glass matrix, called IGM (impermeable graphite matrix), uses a long-term stable inorganic binder which additionally encloses the graphite pore system. The world’s first IGM samples made with irradiated graphite have been manufactured in CIEMAT facilities. The durability of the matrix is investigated in leaching experiments in deionized water and granitic bentonite water. The results show that ∼0.05% of 14C is leached. A species of organic carbon was found as formate and oxalate (∼10–1 mg/L). CO was detected as volatile specie in both media in the first leaching steps; for deionized water (∼3.101 mg/L) and in granitic bentonite water (ranging 1.101–3.101 mg/L). These low values demonstrated the durability of the IGM glass matrix for final disposal.
Carbon-14 (radiocarbon, 14C) is a long-lived radionuclide (5730 yr) of interest regarding the safety for the management of intermediate level wastes (ILW). The present study gives an overview of the release of 14C from irradiated Zircaloy cladding in alkaline media. 14C is found either in the alloy part of Zircaloy cladding due to the neutron activation of 14N impurities by 14N(n,p)14C reaction, or in the oxide layer (ZrO2) formed at the metal surface by the neutron activation of 17O from UO2 or (U-Pu)O2 fuel and water from the primary circuit in the reactor by 17O(n,α)14C reaction. Various irradiated and unirradiated Zircaloys have been studied. The total 14C inventory has been determined both experimentally and by calculations. The results seem to be in good agreement. Leaching experiments were conducted in alkaline media for several time durations. 14C was mainly released as carboxylic acids. Further, corrosion measurements were performed by using both hydrogen measurements and electrochemical measurements. The corrosion rate (CR) ranges from a few nm/yr to 100 nm/yr depending on the surface conditions and the method used for measurement. From a safety assessment point of view, the instant release fraction (IRF) was determined on irradiated Zircaloy-2. The results showed that the 14C inventory in the oxide was significantly below the 20% commonly used in safety case assessments.
Radiocarbon (14C or carbon-14, half-life 5730 yr) is a key radionuclide in the assessment of the safety of a geological disposal facility (GDF) for radioactive waste. In particular, the radiological impact of gaseous carbon-14 bearing species has been recognized as a potential issue. Irradiated steels are one of the main sources of carbon-14 in the United Kingdom’s radioactive waste inventory. However, there is considerable uncertainty about the chemical form(s) in which the carbon-14 will be released. The objective of the work was to measure the rate and speciation of carbon-14 release from irradiated 316L(N) stainless steel on leaching under high-pH anoxic conditions, representative of a cement-based near field for low-heat generating wastes. Periodic measurements of carbon-14 releases to both the gas phase and to solution were made in duplicate experiments over a period of up to 417 days. An initial fast release of carbon-14 from the surface of the steel is observed during the first week of leaching, followed by a drop in the rate of release at longer times. Carbon-14 is released primarily to the solution phase with differing fractions released to the gas phase in the two experiments: about 1% of the total release in one and 6% in the other. The predominant dissolved carbon-14 releases are in inorganic form (as 14C-carbonate) but also include organic species. The predominant gas-phase species are hydrocarbons with a smaller fraction of 14CO (which may include some volatile oxygen-containing carbon-species). The experiments are continuing, with final sampling and termination planned after leaching for a total of two years.
Radiocarbon (14C) is a key radionuclide in the assessment of the safety of underground geological disposal facilities for radioactive wastes, and the understanding of the 14C behavior in stainless steel may lead to a re-evaluation of the near-surface repository for the disposal of wastes containing this radionuclide in high concentrations. To achieve this objective, leaching experiments were planned for two different scenarios. The first is where the leaching solution, NaOH solution of pH ca. 12 in aerobic conditions, simulates the expected conditions in a cement-based near-surface repository over long time periods. The other one uses an acid solution of 1M H3PO4, which has been proved as a high efficiency chemical removal agent of 14C in graphite. The development of both analytical methods and protocols to measure the release of 14C from the activated steel samples and the speciation in the aqueous and gaseous phase has been undertaken as part of the EC CAST (CArbon-14 Source Term) project. Analytical methods, suitable for identifying and quantifying low molecular weight organic molecules, comprise ion chromatography (IC) and gas chromatography coupled to mass spectrometry (GC-MS); they are described for aqueous and gaseous samples, respectively. In this paper the preparation of leaching experiments to measure the release of 14C and the results obtained are described.
Introduction: Safe and efficient handovers between emergency medical services (EMS) practitioners and emergency nurses are vital as poor transitions may lead to loss of information and place patients at risk for adverse events. We conducted a mixed methods systematic review to a) examine factors that disrupt or improve handovers from EMS practitioners to emergency department nurses, and b) investigate the effectiveness of interventional strategies that lead to improvements in communication and fewer adverse events. Methods: We searched electronic databases (DARE, MEDLINE, EMBASE, Cochrane, CINAHL, Joanna Briggs Institute EBP; Communication Abstracts); grey literature (grey literature databases, organization websites, querying experts in emergency medicine); and reference lists of the included studies. Citation tracking was conducted for the included studies. Two reviewers independently screened titles/abstracts and full-texts for inclusion and methodological quality using the Effective Public Health Practice Project Quality Assessment Tool for quantitative studies and the Joanna Briggs Institute Critic Appraisal Checklist for Qualitative Research. Narrative and thematic synthesis were conducted to integrate and explore relationships within the data. Results: Twenty-two studies were included in this review from the 6150 records initially retrieved. Our analysis suggests that qualitative, quantitative, and mixed methods research approaches have been utilized to explore handovers. Studies (n=11) have predominantly explored existing patterns of handovers focusing on barriers and facilitators. Interventions (e.g. multimedia transmission of pre-hospital information, tailored e-learning program) were investigated in five studies. Results suggest that lack of formal handover training, workflow interruptions, workload, and strained working relationships between EMS and nursing are perceived threats to optimal handovers. Conclusion: The findings from this review can inform the development of handover interventions and contribute to a more rigorous approach to researching handovers between EMS practitioners and emergency nurses. Furthermore, there is a need for studies in which specific interventions to optimize handovers are examined.
Synthesis maps of stellar OH maser emission have revealed that the OH lies in expanding spherical shells typically about 1016 cm in diameter. From the maps and the expansion velocity, derived from the OH spectrum, stellar mass loss rates may be determined. Typical values are 10−5 M⊙/yr. An important application of the stellar OH masers is in the estimation of stellar distances.
A prompt radio burst has been observed from the supernova 1987a in the Large Magellanic Cloud. Observations were made at 0.843, 1.415, 2.29, and 8.41 GHz. At frequencies around 1 GHz, the peak flux density reached about 150 mJy and occurred within four days of the supernova. This event may be a weak precursor to a major radio outburst of the type previously observed in other extragalactic supernovae. Radio monitoring of the supernova is continuing at each of the above frequencies, and coordination is underway of a southern hemisphere VLBI array to map the radio outburst region as it expands. Differential astrometry carried out on prime-focus plates taken with the Anglo-Australian telescope indicates that the component, star 1, of Sanduleak's star SK-69202 is within 0.05 ± 0.13 arcsec of the supernova.
The Parkes - Tidbinbilla Interferometer is a radio-linked interferometer using the 64-m telescope at Parkes together with one of the NASA antennas (34-m or 64-m) at Tidbinbilla. With a baseline of 275km, it is currently the world's longest real-time interferometer, and is usable at frequencies of 1.6, 2.3, and 8.4 GHz to give angular resolutions of 0.13, 0.09, and 0.03 arcsec respectively, with a sensitivity of 1–2 mJy rms in 5 minutes at a bandwidth of up to 10MHz.
A study was conducted to estimate the genetic relationship between weaning weight and milk yield in Nguni cattle. Milk yield data (n=125) were collected from 116 Nguni cows from Mara Research Station located in Limpopo Province and Loskop South Farm located in Mpumalanga Province using the weigh-suckle-weigh technique. Weaning weight data (n=19 065) were obtained from stud Nguni cattle from 146 herds distributed throughout South Africa. Estimates of (co)variance components for milk yield and weaning weight were calculated using PEST and VCE softwares. The average weaning weight, age of the calf at weaning and 24-h milk yield was 158.94 kg, 210 days and 5.25 kg/day, respectively. Heritability estimates for milk yield, direct and maternal weaning weight were 0.22±0.238, 0.47±0.039 and 0.25±0.029, respectively. Estimates of genetic correlations for milk yield and maternal weaning weight, milk yield and direct weaning weight, direct and maternal weaning weight were 0.97±0.063, −0.71±0.416 and −0.56±0.247, respectively. The results indicate that maternal weaning weight is genetically highly predictive of milk yield in Nguni cattle. Maternal breeding values for weaning weight could therefore be used as a selection criterion to improve milk yield in Nguni cattle.
The Resource Centers for Minority Aging Research (RCMAR) program was launched in 1997. Its goal is to build infrastructure to improve the well-being of older racial/ethnic minorities by identifying mechanisms to reduce health disparities.
Its primary objectives are to mentor faculty in research addressing the health of minority elders and to enhance the diversity of the workforce that conducts elder health research by prioritizing the mentorship of underrepresented diverse scholars.
Through 2015, 12 centers received RCMAR awards and provided pilot research funding and mentorship to 361 scholars, 70% of whom were from underrepresented racial/ethnic groups. A large majority (85%) of RCMAR scholars from longstanding centers continue in academic research. Another 5% address aging and other health disparities through nonacademic research and leadership roles in public health agencies.
Longitudinal, team-based mentoring, cross-center scholar engagement, and community involvement in scholar development are important contributors to RCMAR’s success.
The prenatal environment is now recognized as a key driver of non-communicable disease risk later in life. Within the developmental origins of health and disease (DOHaD) paradigm, studies are increasingly identifying links between maternal morbidity during pregnancy and disease later in life for offspring. Nutrient restriction, metabolic disorders during gestation, such as diabetes or obesity, and maternal immune activation provoked by infection have been linked to adverse health outcomes for offspring later in life. These factors frequently co-occur, but the potential for compounding effects of multiple morbidities on DOHaD-related outcomes has not received adequate attention. This is of particular importance in low- or middle-income countries (LMICs), which have ongoing high rates of infectious diseases and are now experiencing transitions from undernutrition to excess adiposity. The purpose of this scoping review is to summarize studies examining the effect and interaction of co-occurring metabolic or nutritional stressors and infectious diseases during gestation on DOHaD-related health outcomes. We identified nine studies in humans – four performed in the United States and five in LMICs. The most common outcome, also in seven of nine studies, was premature birth or low birth weight. We identified nine animal studies, six in mice, two in rats and one in sheep. The interaction between metabolic/nutritional exposures and infectious exposures had varying effects including synergism, inhibition and independent actions. No human studies were specifically designed to assess the interaction of metabolic/nutritional exposures and infectious diseases. Future studies of neonatal outcomes should measure these exposures and explicitly examine their concerted effect.
Imaging bundles provide a convenient way to translate a spatially coherent image, yet conventional imaging bundles made from silica fibre optics typically remain expensive with large losses due to poor filling factors (~40%). We present the characterisation of a novel polymer imaging bundle made from poly(methyl methacrylate) (PMMA) that is considerably cheaper and a better alternative to silica imaging bundles over short distances (~1 m; from the middle to the edge of a telescope’s focal plane). The large increase in filling factor (92% for the polymer imaging bundle) outweighs the large increase in optical attenuation from using PMMA (1 dB/m) instead of silica (10−3 dB/m). We present and discuss current and possible future multi-object applications of the polymer imaging bundle in the context of astronomical instrumentation including: field acquisition, guiding, wavefront sensing, narrow-band imaging, aperture masking, and speckle imaging. The use of PMMA limits its use in low-light applications (e.g., imaging of galaxies); however, it is possible to fabricate polymer imaging bundles from a range of polymers that are better suited to the desired science.
Africa is experiencing a rapid increase in adult obesity and associated cardiometabolic diseases (CMDs). The H3Africa AWI-Gen Collaborative Centre was established to examine genomic and environmental factors that influence body composition, body fat distribution and CMD risk, with the aim to provide insights towards effective treatment and intervention strategies. It provides a research platform of over 10 500 participants, 40–60 years old, from Burkina Faso, Ghana, Kenya and South Africa. Following a process that involved community engagement, training of project staff and participant informed consent, participants were administered detailed questionnaires, anthropometric measurements were taken and biospecimens collected. This generated a wealth of demographic, health history, environmental, behavioural and biomarker data. The H3Africa SNP array will be used for genome-wide association studies. AWI-Gen is building capacity to perform large epidemiological, genomic and epigenomic studies across several African counties and strives to become a valuable resource for research collaborations in Africa.
Arctic sea ice is melting, slowly but inexorably. As the ice disappears, mankind will be afforded access to regions and activities, including commercial fishing, that have been inaccessible for our entire recorded history. There is currently no regulatory body or mechanism in the high seas Arctic (also referred to as the central Arctic Ocean) to conserve and manage fish stocks, the distribution and concentration of which are poorly understood, and that might be the target of commercial fisheries. This article examines the extent and nature of ice recession in the Arctic, and its likely effect on the accessibility of central Arctic ocean fisheries to commercial exploitation. It then discusses what is known of Arctic fish stocks, both those already extant, and those that might become established or enhanced as a result of changing environmental conditions. It examines international regimes for managing fish stocks that exist either in whole or in part in global maritime commons, and existing fisheries governance mechanisms in the Arctic, and finds them to be lacking. Finally, using the Bering Sea Arctic pollock stock collapse case study as a historical analogue, this article contends that the time is now for putting in place a regional fisheries management organisation to manage and conserve central Arctic Ocean fish stocks.