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To understand the relationship between drug use, food insecurity (FI) and mental health among men who have sex with men (MSM).
Cohort study (2014–2019) with at least one follow-up.
Visits at 6-month intervals included self-assessment for FI and depressive symptoms. Urine testing results confirmed drug use. Factors associated with FI were assessed using multiple logistic regression with random effects for repeated measures. General structural equation modelling tested whether FI mediates the relationship between drug use and depressive symptoms.
Data were from HIV-positive and high-risk HIV-negative MSM in Los Angeles, CA (n 431; 1192 visits).
At baseline, FI was reported by 50·8 % of participants, depressive symptoms in 36·7 % and 52·7 % of urine screening tests were positive for drugs (i.e. marijuana, opioids, methamphetamine, cocaine and ecstasy). A positive drug test was associated with a 96 % increase in the odds of being food insecure (95 % CI 1·26, 3·07). Compared to those with high food security, individuals with very low food security have a nearly sevenfold increase in the odds of reporting depressive symptoms (95 % CI 3·71, 11·92). Findings showed 14·9 % of the association between drug use (exposure) and depressive symptoms (outcome) can be explained by FI (mediator).
The prevalence of FI among this cohort of HIV-positive and high-risk HIV-negative MSM was high; the association between drug use and depressive symptoms was partially mediated by FI. Findings suggest that enhancing access to food and nutrition may improve mood in the context of drug use, especially among MSM at risk for HIV transmission.
Conservation tillage adoption continues to be threatened by glyphosate and acetolactate synthase–resistant Palmer amaranth and other troublesome weeds. Field experiments were conducted from autumn 2010 through crop harvest in 2013 at two locations in Alabama to evaluate the effect of integrated management practices on weed control and seed cotton yield in glyphosate-resistant cotton. The effects of a cereal rye cover crop using high- or low-biomass residue, followed by wide or narrow within-row strip tillage and three PRE herbicide regimens were evaluated. The three PRE regimens were (1) pendimethalin at 0.84 kg ae ha−1 plus fomesafen at 0.28 kg ai ha−1 applied broadcast, (2) pendimethalin plus fomesafen applied banded on the row, or (3) no PRE. Each PRE treatment was followed by (fb) glyphosate (1.12 kg ae ha−1) applied POST fb layby applications of diuron (1.12 kg ai ha−1) plus monosodium methanearsonate (2.24 kg ai ha−1). Low-residue plots ranged in biomass from 85 to 464 kg ha−1, and high-biomass residue plots ranged from 3,119 to 6,929 kg ha−1. In most comparisons, surface disturbance width, residue amount, and soil-applied herbicide placement did not influence within-row weed control; however, broadcast PRE resulted in increased carpetweed, large crabgrass, Palmer amaranth, tall morning-glory, and yellow nutsedge weed control in row middles compared with plots receiving banded PRE. In addition, high-residue plots had increased carpetweed, common purslane, large crabgrass, Palmer amaranth, sicklepod, and tall morning-glory weed control between rows. Use of banded PRE herbicides resulted in equivalent yield and revenue in four of six comparisons compared with those with broadcast PRE herbicide application; however, this would likely result in many between-row weed escapes. Thus, conservation tillage cotton would benefit from broadcast soil-applied herbicide applications regardless of residue amount and tillage width when infested with Palmer amaranth and other troublesome weed species.
The first demonstration of laser action in ruby was made in 1960 by T. H. Maiman of Hughes Research Laboratories, USA. Many laboratories worldwide began the search for lasers using different materials, operating at different wavelengths. In the UK, academia, industry and the central laboratories took up the challenge from the earliest days to develop these systems for a broad range of applications. This historical review looks at the contribution the UK has made to the advancement of the technology, the development of systems and components and their exploitation over the last 60 years.
Traditionally, Roman temples and shrines in Britain have been contextualised in relation to wider ‘Roman’ religious practices. Until recently, considerations of architectural form and named deities have dominated discussions. The wider turn in archaeological discourse recognising ritual in everyday contexts has highlighted the importance of lived experience and landscape practice in shaping belief. Here we reflect on the implications of such ideas when approaching ritual practice at Roman temples, using a recently excavated example from Wiltshire, southern Britain, as a case study. The exceptional artefactual assemblages from the site demonstrate the importance of local and regional landscape practices and belief in shaping ritual practice in a sacred space. In addition, geophysical survey and analysis of Portable Antiquities Scheme (PAS) finds suggests that those occupying the landscape had long-term access to wealth. Deposition in the temple itself indicates the continuing importance attached to prehistoric objects in the Roman period, but also to the adoption of new votive practices of miniaturisation, mutilation and sacrifice. These rituals, although part of wider grammars of religious behaviour, had their roots in specific local contexts. Our detailed analyses provide a picture of a temple dedicated to a previously unknown local god, Bregneus, framed against that of an active community involved in farming, iron processing, quarrying, hunting and woodland management.
Many studies document cognitive decline following specific types of acute illness hospitalizations (AIH) such as surgery, critical care, or those complicated by delirium. However, cognitive decline may be a complication following all types of AIH. This systematic review will summarize longitudinal observational studies documenting cognitive changes following AIH in the majority admitted population and conduct meta-analysis (MA) to assess the quantitative effect of AIH on post-hospitalization cognitive decline (PHCD).
We followed Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Selection criteria were defined to identify studies of older age adults exposed to AIH with cognitive measures. 6566 titles were screened. 46 reports were reviewed qualitatively, of which seven contributed data to the MA. Risk of bias was assessed using the Newcastle–Ottawa Scale.
The qualitative review suggested increased cognitive decline following AIH, but several reports were particularly vulnerable to bias. Domain-specific outcomes following AIH included declines in memory and processing speed. Increasing age and the severity of illness were the most consistent risk factors for PHCD. PHCD was supported by MA of seven eligible studies with 41,453 participants (Cohen’s d = −0.25, 95% CI [−0.02, −0.49] I2 35%).
There is preliminary evidence that AIH exposure accelerates or triggers cognitive decline in the elderly patient. PHCD reported in specific contexts could be subsets of a larger phenomenon and caused by overlapping mechanisms. Future research must clarify the trajectory, clinical significance, and etiology of PHCD: a priority in the face of an aging population with increasing rates of both cognitive impairment and hospitalization.
It is traditionally taught that the location to place an ultrasound probe to detect a pneumothorax with point-of-care ultrasound (POCUS) is the anterior chest, given the theory that air will collect at the least dependent area in the supine patient. There is a wide variety of scanning protocols with varying accuracy and completeness. We sought to assess the optimal area to scan for diagnosing pneumothorax by mapping the location of traumatic pneumothorax on computed tomography (CT).
Patients were selected after a retrospective cohort of adult patients who presented to a regional trauma center with a pneumothorax diagnosed on CT. Data were extracted using a standardized data collection tool, and 20% of charts were reviewed by two reviewers. Predefined zones were used to map the areas of pneumothoraces. Theoretical sensitivity and 95% confidence intervals (CIs) are reported.
A total of 203 traumatic pneumothoraces were reviewed from 2006 to 2016. The majority of the pneumothoraces were found in an area defined by the para-sternal border and the mid-clavicular line from the inferior aspect of the clavicle to the physiologic lung point (liver on the right, heart on the left). The theoretical sensitivity for pneumothorax of scanning this area was 91.6% (95% CI, 86.9–95%).
This study suggests any POCUS scanning protocol for traumatic pneumothorax should include an area from the inferior border of the clavicle at the parasternal border down to the liver or cardiac lung points and then the mid clavicular line down to the liver or cardiac lung points.
Archaeologists have long subjected Clovis megafauna kill/scavenge sites to the highest level of scrutiny. In 1987, a Columbian mammoth (Mammuthus columbi) was found in spatial association with a small artifact assemblage in Converse County, Wyoming. However, due to the small tool assemblage, limited nature of the excavations, and questions about the security of the association between the artifacts and mammoth remains, the site was never included in summaries of human-killed/scavenged megafauna in North America. Here we present the results of four field seasons of new excavations at the La Prele Mammoth site that confirm the presence of an associated cultural occupation based on geologic context, artifact attributes, spatial distributions, protein residue analysis, and lithic microwear analysis. This new work identified a more extensive cultural occupation including the presence of multiple discrete artifact clusters in close proximity to the mammoth bone bed. This study confirms the presence of a second Clovis mammoth kill/scavenge site in Wyoming and shows the value in revisiting proposed terminal Pleistocene kill/scavenge sites.
Computational modeling is an important aspect of the research on nuclear waste materials. In particular, atomistic simulations, when used complementary to experimental efforts, contribute to the scientific basis of safety case for nuclear waste repositories. Here we discuss the state-of-the-art and perspectives of atomistic modeling for nuclear waste management on a few cases of successful synergy of atomistic simulations and experiments. In particular, we discuss here: (1) the potential of atomistic simulations to investigate the uranium oxidation state in mixed-valence uranium oxides and (2) the ability of cementitious barrier materials to retain radionuclides such as 226Ra and 90Sr, and of studtite/metastudtite secondary peroxide phases to incorporate actinides such as Np and Am. The new contribution we make here is the computation of the incorporation of Sr by C-S-H (calcium silicate hydrate) phases.
Radnor Lake State Natural Area in Nashville, TN, has cedar glades that contain the endangered perennial herb wild dill [Perideridia americana (Nutt. ex DC.) Rchb.] and the invasive shrub Amur honeysuckle [Lonicera maackii (Rupr.) Herder]. This research examined whether L. maackii treatment in the Radnor Lake State Natural Area cedar glades is followed by an increase in P. americana plants. A grid of 60 adjacent 2 m by 4 m plots was placed in five cedar glades to encompass the P. americana population. With great care to protect P. americana, the annual treatment for L. maackii was to pull plants ≤1-m tall from the ground; and to cut stems >1-m tall and then treat the stumps with glyphosate. The t-tests of means for the log natural of the number of plants in the 60 plots (significance level of P-value = 0.05) were used to compare pretreatment L. maackii and P. americana counts with posttreatment counts in 2018 and P. americana counts at leaf out and flowering in 2018. The L. maackii population was significantly smaller (P-value < 0.001) in 2018 than pretreatment at all five sites. When pretreatment in 2014 and 2015 was compared with posttreatment in 2018 for the P. americana populations, the increases were significant at the Cheek, Harris 2, Hideaway, and Norfleet sites, but the increase at East Hall Farm was not significant. White-tailed deer (Odocoileus virginianus Zimmermann) trampling was the explanation given for the decreases in P. americana from leaf out to flowering at all five sites in 2018. Browsing was evident only at Hideaway, which had a greater loss for P. americana from leaf out to flowering in 2018 than the combined losses for the Cheek, East Hall Farm, Harris 2, and Norfleet sites. The research informed the creation of adaptive management decisions regarding monitoring and treatment of the invasive species L. maackii for an endangered species.
The expanding range of disease modifying therapies (DMT) for relapsing-remitting multiple sclerosis (RRMS) has led to increased interest in the relative effects of different DMTs. Previous mixed treatment comparisons (MTCs) have used different methods to address similar questions highlighting the need for a consistent approach to the assessment of treatments in RRMS.
We compared the methodology of six published MTCs of DMTs for RRMS identified by a systematic search of the literature. We assessed sources of evidence, DMTs included, outcomes reported and methods of data synthesis.
All six MTCs were based on systematic reviews that included randomized controlled trials (RCTs). MS relapse was reported as the rate ratio based on annualised relapse rates (four MTCs) and as odds ratios or relative risk (one MTC each) based on the proportion with relapse. The analysis of relapse included between sixteen and twenty-seven RCTs and seven to twenty DMTs in different MTCs. One MTC reported both disability progression confirmed after three months (CDP3M) and disability progression confirmed after six months (CDP6M) as hazard ratios. One MTC combined CDP3M and CDP6M as a single outcome. One MTC reported only CDP3M based on hazard ratios. Two MTCs reported only CDP6M as either odds ratios or risk ratios (one MTC each). In one MTC the definition of disability progression was not reported. The analysis of disability included between seven and twenty-six RCTs and between six and nineteen DMTs in different MTCs. All six MTCs fitted a random effects MTC model using either Bayesian (four MTCs) or frequentist (two MTCs) methods.
There is substantial heterogeneity between published MTCs in RRMS with regard to inclusion criteria, outcome definitions, effect measures and statistical methods. There is a clear requirement for a consistent approach to health technology assessment of DMTs for RRMS.
We apply n- and p-type polycrystalline silicon (poly-Si) films on tunneling SiOx to form passivated contacts to n-type Si wafers. The resulting induced emitter and n+/n back surface field junctions of high carrier selectivity and low contact resistivity enable high efficiency Si solar cells. This work addresses the materials science of their performance governed by the properties of the individual layers (poly-Si, tunneling oxide) and more importantly, by the process history of the cell as a whole. Tunneling SiOx layers (<2 nm) are grown thermally or chemically, followed by a plasma enhanced chemical vapor deposition growth of p+ or n+ doped a-Si:H. The latter is thermally crystallized into poly-Si, resulting in grain nucleation and growth as well as dopant diffusion within the poly-Si and penetration through the tunneling oxide into the Si base wafer. The cell process is designed to improve the passivation of both oxide interfaces and tunneling transport through the oxide. A novel passivation technique involves coating of the passivated contact and whole cell with atomic layer deposited Al2O3 and activating them at 400 °C. The resulting excellent passivation persists after subsequent chemical removal of the Al2O3. The preceding cell process steps must be carefully tailored to avoid structural and morphological defects, as well as to maintain or improve passivation, and carrier selective transport. Furthermore, passivated contact metallization presents significant challenges, often resulting in passivation loss. Suggested remedies include improved Si cell wafer surface morphology (without micropyramids) and postdeposited a-Si:H capping layers over the poly-Si.
We demonstrated the fabrication of 10 emitters InGaN laser diode array of the
maximum output power of 9 W at 420 nm. The device as a whole has the
differential efficiency of above 1 W/A. The maximum output power is limited to 9
W (pulse operation) by catastrophic mirror damage or to around 5 W in CW
operation by thermal roll-over. Larger arrays with stripes width of around 15
µm and numbers of emitters up to 20 should enable reaching 20 W, which
is suitable for light engine of desktop projectors and a building block of
cinema theater projectors.
This triennium has seen progress in a number of directions related to Commission 20 objectives. Foremost, the growth in the number of astrometric observations of small solar system bodies continues to accelerate and the total number of measurements recorded by the Minor Planet Center now exceeds 135 million. Currently the Pan-STARRS project and the Catalina Sky Survey (CSS) dominate detection and discovery efforts, while the NEO-WISE space mission contributes infrared detections valuable for understanding the size distribution of populations. Looking forward, the Large Synoptic Survey Telescope (LSST) is now funded and in construction on Cerro Pachon in Chile. LSST has the potential to revolutionize the field by conducting a multi-color, ten-year, all-sky survey with a limiting magnitude ~24.5 in the r-band. Survey operations are set to begin in 2022.