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Signal detection limit (SDL), limit of detection (LOD), and limit of quantitation of a portable Raman spectrometer were measured for smokeless gunpowder stabilizers, diphenylamine (DPA) and ethyl centralite (EC), in acetone, acetonitrile, ethanol, and methanol. Acetone yielded the lowest LOD for three of four DPA peaks, and acetonitrile yielded the lowest LOD for two of three EC peaks and the remaining DPA peak. When gold nanoparticles were added to the DPA solutions in acetone and acetonitrile, statistically significant changes were observed (DPA peak position, full width at half maximum, and/or total area) and SDL was improved for the majority of all peaks in both solvents.
This study investigates suicide risk in late childhood and early adolescence in relation to a family-centered intervention, the Family Check-Up, for problem behavior delivered in early childhood. At age 2, 731 low-income families receiving nutritional services from Women, Infants, and Children programs were randomized to the Family Check-Up intervention or to a control group. Trend-level main effects were observed on endorsement of suicide risk by parents or teachers from ages 7.5 to 14, with higher rates of suicide risk endorsement in youth in the control versus intervention condition. A significant indirect effect of intervention was also observed, with treatment-related improvements in inhibitory control across childhood predicting reductions in suicide-related risk both at age 10.5, assessed via diagnostic interviews with parents and youth, and at age 14, assessed via parent and teacher reports. Results add to the emerging body of work demonstrating long-term reductions in suicide risk related to family-focused preventive interventions, and highlight improvements in youth self-regulatory skills as an important mechanism of such reductions in risk.
The main risk factor for acquisition of antimicrobial-resistant bacteria (ARB) is antimicrobial exposure, although acquisition can occur in their absence. The aim of this study was to quantify the proportion of patients who acquire ARB without antimicrobial exposure.
We searched Medline, Embase, and the Cochrane library for publications between January 1, 2000, and July 24, 2017, to identify studies of ARB acquisition in endemic settings. Studies required collection of serial surveillance cultures with acquisition defined as a negative baseline culture and a subsequent positive culture for an ARB, including either multidrug-resistant gram-negative bacteria or antimicrobial-resistant enterococci. Intervention studies were excluded. For each study, the proportion of patients who acquired an ARB but were not exposed to antimicrobials during the study period was quantified.
A total of 4,233 citations were identified; 147 underwent full-text review. Of these, 10 studies met inclusion criteria; 7 studies were considered to be at low risk of bias; and 6 studies were conducted in the intensive care unit (ICU) setting. The overall summary estimate for the proportion of patients who were not exposed to antimicrobials among those who acquired an ARB was 16.6% (95% CI, 7.8%–31.8%; P < .001), ranging from 0% to 57.1%. We observed no heterogeneity in the ICU studies but high heterogeneity among the non-ICU studies.
In most included studies, a subset of patients acquired an ARB but were not exposed to antimicrobials. Future studies need to address transmission dynamics of ARB acquisition in the absence of antimicrobials.
People with cerebral palsy (CP) are less physically active than the general population and, consequently, are at increased risk of preventable disease. Evidence indicates that low-moderate doses of physical activity can reduce disease risk and improve fitness and function in people with CP. Para athletes with CP typically engage in ‘performance-focused’ sports training, which is undertaken for the sole purpose of enhancing sports performance. Anecdotally, many Para athletes report that participation in performance-focused sports training confers meaningful clinical benefits which exceed those reported in the literature; however, supporting scientific evidence is lacking. The aim of this paper is to describe the protocol for an 18-month study evaluating the clinical effects of a performance-focused swimming training programme for people with CP who have high support needs.
This study will use a concurrent multiple-baseline, single-case experimental design across three participants with CP who have high support needs. Each participant will complete a five-phase trial comprising: baseline (A1); training phase 1 (B1); maintenance phase 1 (A2); training phase 2 (B2); and maintenance phase 2 (A3). For each participant, measurement of swim velocity, health-related quality of life and gross motor functioning will be carried out a minimum of five times in each of the five phases.
The study described will produce Level II evidence regarding the effects of performance-focused swimming training on clinical outcomes in people with CP who have high support needs. Findings are expected to provide an indication of the potential for sport to augment outcomes in neurological rehabilitation.
Kochia is one of the most problematic weeds in the United States. Field studies were conducted in five states (Wyoming, Colorado, Kansas, Nebraska, and South Dakota) over 2 yr (2010 and 2011) to evaluate kochia control with selected herbicides registered in five common crop scenarios: winter wheat, fallow, corn, soybean, and sugar beet to provide insight for diversifying kochia management in crop rotations. Kochia control varied by experimental site such that more variation in kochia control and biomass production was explained by experimental site than herbicide choice within a crop. Kochia control with herbicides currently labeled for use in sugar beet averaged 32% across locations. Kochia control was greatest and most consistent from corn herbicide programs (99%), followed by soybean (96%) and fallow (97%) herbicide programs. Kochia control from wheat herbicide programs was 93%. With respect to the availability of effective herbicide options, glyphosate-resistant kochia control was easiest in corn, soybean, and fallow, followed by wheat; and difficult to manage with herbicides in sugar beet.
Starting in 2016, we initiated a pilot tele-antibiotic stewardship program at 2 rural Veterans Affairs medical centers (VAMCs). Antibiotic days of therapy decreased significantly (P < .05) in the acute and long-term care units at both intervention sites, suggesting that tele-stewardship can effectively support antibiotic stewardship practices in rural VAMCs.
Though theory suggests that individual differences in neuroticism (a tendency to experience negative emotions) would be associated with altered functioning of the amygdala (which has been linked with emotionality and emotion dysregulation in childhood, adolescence, and adulthood), results of functional neuroimaging studies have been contradictory and inconclusive. We aimed to clarify the relationship between neuroticism and three hypothesized neural markers derived from functional magnetic resonance imaging during negative emotion face processing: amygdala activation, amygdala habituation, and amygdala-prefrontal connectivity, each of which plays an important role in the experience and regulation of emotions. We used general linear models to examine the relationship between trait neuroticism and the hypothesized neural markers in a large sample of over 500 young adults. Although neuroticism was not significantly associated with magnitude of amygdala activation or amygdala habituation, it was associated with amygdala–ventromedial prefrontal cortex connectivity, which has been implicated in emotion regulation. Results suggest that trait neuroticism may represent a failure in top-down control and regulation of emotional reactions, rather than overactive emotion generation processes, per se. These findings suggest that neuroticism, which has been associated with increased rates of transdiagnostic psychopathology, may represent a failure in the inhibitory neurocircuitry associated with emotion regulation.
Background: Cervical sponylotic myelopathy (CSM) may present with neck and arm pain. This study investiagtes the change in neck/arm pain post-operatively in CSM. Methods: This ambispective study llocated 402 patients through the Canadian Spine Outcomes and Research Network. Outcome measures were the visual analogue scales for neck and arm pain (VAS-NP and VAS-AP) and the neck disability index (NDI). The thresholds for minimum clinically important differences (MCIDs) for VAS-NP and VAS-AP were determined to be 2.6 and 4.1. Results: VAS-NP improved from mean of 5.6±2.9 to 3.8±2.7 at 12 months (P<0.001). VAS-AP improved from 5.8±2.9 to 3.5±3.0 at 12 months (P<0.001). The MCIDs for VAS-NP and VAS-AP were also reached at 12 months. Based on the NDI, patients were grouped into those with mild pain/no pain (33%) versus moderate/severe pain (67%). At 3 months, a significantly high proportion of patients with moderate/severe pain (45.8%) demonstrated an improvement into mild/no pain, whereas 27.2% with mild/no pain demonstrated worsening into moderate/severe pain (P <0.001). At 12 months, 17.4% with mild/no pain experienced worsening of their NDI (P<0.001). Conclusions: This study suggests that neck and arm pain responds to surgical decompression in patients with CSM and reaches the MCIDs for VAS-AP and VAS-NP at 12 months.
After Mexican sugar producers gained unlimited, tariff-free access to the U.S. market in 2008, U.S. and Mexican governments bilaterally agreed to constrain Mexico’s sugar exports to the United States because of dumping allegations by U.S. producers in December 2014. This analysis employs a dynamic partial equilibrium model to estimate the price and welfare impacts of the U.S.-Mexico agreement by simulating the reimplementation of North American Free Trade Agreement sugar policies. Estimates suggest liberalizing the market would decrease U.S. sugar prices, translating to an average annual decrease in producer surplus of approximately $660 million and increase in consumer surplus of $1.67 billion across the simulation.
Geophysical survey and excavations from 2010–2016 at Lawrenz Gun Club (11CS4), a late pre-Columbian village located in the central Illinois River valley in Illinois, identified 10 mounds, a central plaza, and dozens of structures enclosed within a stout 10 hectare bastioned palisade. Nineteen radiocarbon (14C) measurements were taken from single entities of wood charcoal, short-lived plants, and animal bones. A site chronology has been constructed using a Bayesian approach that considers the stratigraphic contexts and feature formation processes. The village was host to hundreds of years of continuous human activity during the Mississippi Period. Mississippian activity at the site is estimated to have begun in cal AD 990–1165 (95% probability), ended in cal AD 1295–1450 (95% probability), and lasted 150–420 yr (95% probability) in the primary Bayesian model with similar results obtained in two alternative models. The palisade is estimated to have been constructed in cal AD 1150–1230 (95% probability) and was continuously repaired and rebuilt for 15–125 yr (95% probability), probably for 40–85 yr (68% probability). Comparison to other studies demonstrates that the bastioned palisade at Lawrenz was one of the earliest constructed in the midcontinental United States.
Content analysis is the process of turning text into data, with either automated or manual techniques, and it provides a feasible and attractive option for undergraduate students to develop and utilize original data. This article presents a cohesive framework for teaching computerized content analysis in undergraduate political science courses. The article discusses examples of how we have taught the techniques in our own classrooms and provides a framework for a content-analysis research assignment. We describe coding, sources of text data available to students, software recommendations appropriate for students, and write-up issues. In the process, we also discuss various learning opportunities that arise from both the strengths and weaknesses of computerized content analysis as a methodological strategy.
The majority of paediatric Clostridioides difficile infections (CDI) are community-associated (CA), but few data exist regarding associated risk factors. We conducted a case–control study to evaluate CA-CDI risk factors in young children. Participants were enrolled from eight US sites during October 2014–February 2016. Case-patients were defined as children aged 1–5 years with a positive C. difficile specimen collected as an outpatient or ⩽3 days of hospital admission, who had no healthcare facility admission in the prior 12 weeks and no history of CDI. Each case-patient was matched to one control. Caregivers were interviewed regarding relevant exposures. Multivariable conditional logistic regression was performed. Of 68 pairs, 44.1% were female. More case-patients than controls had a comorbidity (33.3% vs. 12.1%; P = 0.01); recent higher-risk outpatient exposures (34.9% vs. 17.7%; P = 0.03); recent antibiotic use (54.4% vs. 19.4%; P < 0.0001); or recent exposure to a household member with diarrhoea (41.3% vs. 21.5%; P = 0.04). In multivariable analysis, antibiotic exposure in the preceding 12 weeks was significantly associated with CA-CDI (adjusted matched odds ratio, 6.25; 95% CI 2.18–17.96). Improved antibiotic prescribing might reduce CA-CDI in this population. Further evaluation of the potential role of outpatient healthcare and household exposures in C. difficile transmission is needed.
Costa Rica and Colombia, two of the earliest Latin American countries to protect many LGBT rights, attempted to amplify those rights and litigate same-sex marriage (SSM) in mid-2000s; however, these attempts sparked a major anti-LGBT backlash by religious and conservative organizations. Yet a decade later, Colombia legalized SSM while Costa Rica still lacks the right to SSM. Using a most-similar systems comparative case study, this study engages the judicial politics literature to explain this divergent outcome. It details how courts, while staying receptive to many individual LGBT rights claims, deferred SSM legalization to popularly elected branches. In spite of the lack of legislative success in both countries, in Colombia a new litigation strategy harnessed that deference to craft a litigated route to legalized SSM. In Costa Rica, the courts’ lack of conditions or deadlines has left SSM foundering in the congress.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
Total reflection X-ray fluorescence (TXRF) analysis of “low Z” elements, Ti, Fe, Ni, Cu, Zn and “high Z” elements, Zr, W, Au, Pb, are required for micro scale semiconductor device production processes. In the past, the W–Lβ X-rays have been used for the analysis of S to Zn.
This paper describes a new three crystal monochromator coupled with a gold direct-drive rotating anode target. This development has produced significant improvements in the sensitivities and LLD's for all measured elements. The monochromator makes the Au Lα (9.71 keV), Au Lβ (11.44 keV) and Au Lγ (13.33 keV) available for routine use in TXRF analyses. The Au Lα X-ray is best used for the lower Z elements, Na to Cu. The best result for W, Cu and Zn are obtained with the Au Lβ X-ray. This is the result of both increased peak intensity and lower background. For the heavier elements, such as Au and Pb, the Au L X-ray yields intensities 100 times higher than what has been achieved in the past.
Over the past few years there has been substantial progress in the TXRF analysis of heavy element surface contamination on silicon wafers. Further advances and improvements are desired in the analytical performance and hardware. Extension of the analytical range to include the light elements is particularly desirable.
In the case of light element analysis, sodium and aluminum impurities have been monitored in the IC production process. The increase of the sodium impurity in a silicon wafer gives rise to a decrease in the insulation in IC devices and the growth of the SiO2 film is disturbed by the prsence of aluminum impurity on the silicon wafer surface.
The Morgantown Energy Research Center of ERDA is studying fouling and slagging of pulverized coal fired boiler tubes resulting from mineral matter contained in the coal. The research is dependent on the development and application of reliable analytical techniques which can be applied to the coal and ash products to determine the mineral interactions responsible for fouling and slagging. X-ray powder diffraction is one of the techniques used to characterize the feed coals and their combustion products. A summary of the methods and techniques applied at MERC is the subject of this paper.