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Enterococcus causes clinically significant bloodstream infections (BSIs). In centers with a higher prevalence of vancomycin resistant enterococcus (VRE) colonization, a common clinical question is whether empiric treatment directed against VRE should be initiated in the setting of a suspected enterococcal BSI. Unfortunately, VRE treatment options are limited, and relatively expensive, and subject patients to the risk of adverse reactions. We hypothesized that the results of VRE colonization screening could predict vancomycin resistance in enterococcal BSI.
We reviewed 370 consecutive cases of enterococcal BSI over a 7-year period at 2 tertiary-care hospitals to determine whether vancomycin-resistant BSIs could be predicted based on known colonization status (ie, patients with swabs performed within 30 days, more remotely, or never tested). We calculated sensitivity and specificity, and we plotted negative predictives values (NPVs) and positive predictive values (PPVs) as a function of prevalence.
A negative screening swab within 30 days of infection yielded NPVs of 90% and 95% in settings where <27.0% and 15.0% of enterococcal BSI are resistant to vancomycin, respectively. In patients with known VRE colonization, the PPV for VRE in enterococcal BSI was >50% at any prevalence exceeding 25%.
The results of a negative VRE screening test result performed within 30 days can help eliminate unnecessary empiric therapy in patients with suspected enterococcal BSI. Conversely, patients with positive VRE screening swabs require careful consideration of empiric VRE-directed therapy when enterococcal BSI appears likely.
This paper summarizes a multi-state, multi-year study assessing the potential for local agriculture in northern New England. While largely rural, this region's agricultural sector differs greatly from the rest of the United States, and demand for locally produced food has been increasing. To assess this unique economic landscape, researchers and Cooperative Extension at the Universities of Maine, New Hampshire, and Vermont investigated four key areas: (1) local food capacities, (2) constraints to agricultural expansion, (3) consumer preferences for local and organic produce, and (4) the role of intermediaries as alternative local food outlets. The project included input from local farmers, Extension members, restaurants, and the general public. We present the four research areas in a sequential, overlapping fashion. The timing of our research was such that each step in the process informed the next and can be used as a template for assessing a region's potential for local agricultural production.
Forty years ago, Knut Fladmark (1979) argued that the Pacific Coast offered a viable alternative to the ice-free corridor model for the initial peopling of the Americas—one of the first to support a “coastal migration theory” that remained marginal for decades. Today, the pre-Clovis occupation at the Monte Verde site is widely accepted, several other pre-Clovis sites are well documented, investigations of terminal Pleistocene subaerial and submerged Pacific Coast landscapes have increased, and multiple lines of evidence are helping decode the nature of early human dispersals into the Americas. Misconceptions remain, however, about the state of knowledge, productivity, and deglaciation chronology of Pleistocene coastlines and possible technological connections around the Pacific Rim. We review current evidence for several significant clusters of early Pacific Coast archaeological sites in North and South America that include sites as old or older than Clovis. We argue that stemmed points, foliate points, and crescents (lunates) found around the Pacific Rim may corroborate genomic studies that support an early Pacific Coast dispersal route into the Americas. Still, much remains to be learned about the Pleistocene colonization of the Americas, and multiple working hypotheses are warranted.
The purpose of this study was to assess the associations of comorbid opioid use disorders and psychiatric disorders with suicide attempts among veterans seeking pain care.
The cohort (N = 226 444) was selected by identifying pain care initiation from 2012 to 2014 using national Veterans Health Administration (VHA) data. Data on opioid use disorders (OUD), psychiatric disorders, medical comorbidity, demographics at baseline, and suicide attempts in the year following the initiation of pain care were extracted from VHA databases. Relative excess risk due to interaction (RERI) was used to assess departure from additivity of effects.
Adjusted models indicated that both comorbid OUD and depression (RERI = 1.07) and comorbid OUD and AUD (RERI = 1.23) were significantly associated with additive risk of suicide attempt. In adjusted multiplicative interaction models, only comorbid OUD and bipolar disorder was significantly associated with suicide attempts; however, this association was protective (HR = 0.54).
The current findings highlight the importance of addressing opioid use disorders and alcohol use disorders and depression together to mitigate the risk of suicidal behavior.
Biological invasions are one of the grand challenges facing society, as exotic species introductions continue to rise and can result in dramatic changes to native ecosystems and economies. The scale of the “biological invasions crisis” spans from hyperlocal to international, involving a myriad of actors focused on mitigating and preventing biological invasions. However, the level of engagement among stakeholders and opportunities to collaboratively solve invasives issues in transdisciplinary ways is poorly understood. The Biological Invasions: Confronting a Crisis workshop engaged a broad group of actors working on various aspects of biological invasions in Virginia, USA—researchers, Extension personnel, educators, local, state, and federal agencies, nongovernmental organizations, and land managers—to discuss their respective roles and how they interact with other groups. Through a series of activities, it became clear that despite shared goals, most groups are not engaging with one another, and that enhanced communication and collaboration among groups is key to designing effective solutions. There is strong support for a multistakeholder coalition to affect change in policy, public education/engagement, and solution design. Confronting the biological invasions crisis will increasingly require engagement among stakeholders.
Silver nanowire (AgNW) diameters are typically characterized by manual measurement from high magnification electron microscope images. Measurement is monotonous and has potential ergonomic hazards. Because of this, statistics regarding wire diameter distribution can be poor, costly, and low-throughput. In addition, manual measurements are of unknown uncertainty and operator bias. In this paper we report an improved microscopy method for diameter and yield measurement of nanowires in terms of speed/automation and reduction of analyst variability. Each step in the process to generate these measurements was analyzed and optimized: microscope imaging conditions, sample preparation for imaging, image acquisition, image analysis, and data processing. With the resulting method, average diameter differences between samples of just a few nanometers can be confidently and statistically distinguished, allowing the identification of subtle incremental improvements in reactor processing conditions, and insight into nucleation and growth kinetics of AgNWs.
Temporal and spatial scarcity of water in semi-arid and seasonal ecosystems often leads to changes in movements and behaviour of large vertebrates, and in the neotropics this dynamic is poorly understood due to logistical and methodological limitations. Here we used camera trapping to elucidate variation in patterns of seasonal use of waterholes and pathways by 10 large-mammal and four large-bird species in the dry forest of north-western Costa Rica. From 2011 to 2015, we deployed trail cameras at 50 locations, including waterholes and three types of pathway (roads, human trails and animal paths). We used Generalized Linear Models to evaluate the effect of location and seasonality on the rates at which independent photographs were taken. We found interacting effects of location and seasonality for the capuchin monkey (Cebus capucinus), the tiger heron (Trigrisoma mexicanum), the white-tailed deer (Odocoileus virginianus) and the tapir (Tapirus bairdii) suggesting that these species were the most influenced by waterholes during the dry season. Comparison of waterhole sites and specific types of pathways (roads, animal paths and human trails) showed that location influenced photo-capture rates of almost all species, suggesting a useful insight to avoid and account for bias in camera trap studies. Furthering our ecological understanding of seasonal water regimes and large vertebrates’ behaviours allow for better understanding of the consequences of climate change on them.
Jaswal & Akhtar provide several quotes ostensibly from people with autism but obtained via the discredited techniques of Facilitated Communication and the Rapid Prompting Method, and they do not acknowledge the use of these techniques. As a result, their argument is substantially less convincing than they assert, and the article lacks transparency.
All herbicides will move off-target to sensitive crops when not applied correctly. Therefore, low-dose applications of flumioxazin and metribuzin were evaluated in soybean at the unifoliate, V2, and V4 growth stages. Rates evaluated were 12.5%, 25%, and 50% of the labeled use rates of 72 and 316 g ai ha−1 of flumioxazin and metribuzin, respectively. Flumioxazin injury was characterized by necrosis and visible height and width reduction. Injury increased with rate 3 d after treatment (DAT), with unifoliate, V2, and V4 soybean injured 15% to 30%, 18% to 27%, and 5% to 8%, respectively. Unifoliate and V4 soybean were injured more than V4 soybean 3 to 14 DAT, but injury decreased to <5% by 42 DAT. Soybean yields in the flumioxazin study were 92% to 96% of the nontreated, resulting in a yield loss of 196 to 393 kg ha−1 and a revenue loss of 71 to 141 US$ ha−1. Metribuzin injury was primarily chlorosis with necrosis and a visible reduction in soybean height and width. Soybean at the V2 growth stage was injured 14% more than V4 soybean 3 DAT, regardless of metribuzin rate. Injury to V2 and V4 soybean was similar 14 DAT, with injury of 21% to 40% across rates. Soybean injury when treated at the V2 and V4 growth stages was 6% to 29% 42 DAT compared to unifoliate soybean at 0 to 17%. Soybean yields in the metribuzin study yields were 96% to 98% of the nontreated. However, a 2% to 4% reduction equates to a loss of 90 to 180 kg ha−1 and a revenue loss of 32 to 65 US$ ha−1. Unifoliate and V2 soybean are more sensitive to a low dose of flumioxazin POST, and V2 and V4 soybean are more sensitive to a low dose of metribuzin POST. Injury and the impact on soybean growth could potentially cause economic loss for a soybean producer.
Due to concerns over increasing fluoroquinolone (FQ) resistance among gram-negative organisms, our stewardship program implemented a preauthorization use policy. The goal of this study was to assess the relationship between hospital FQ use and antibiotic resistance.
Large academic medical center.
We performed a retrospective analysis of FQ susceptibility of hospital isolates for 5 common gram-negative bacteria: Acinetobacter spp., Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa. Primary endpoint was the change of FQ susceptibility. A Poisson regression model was used to calculate the rate of change between the preintervention period (1998–2005) and the postimplementation period (2006–2016).
Large rates of decline of FQ susceptibility began in 1998, particularly among P. aeruginosa, Acinetobacter spp., and E. cloacae. Our FQ restriction policy improved FQ use from 173 days of therapy (DOT) per 1,000 patient days to <60 DOT per 1,000 patient days. Fluoroquinolone susceptibility increased for Acinetobacter spp. (rate ratio [RR], 1.038; 95% confidence interval [CI], 1.005–1.072), E. cloacae (RR, 1.028; 95% CI, 1.013–1.044), and P. aeruginosa (RR, 1.013; 95% CI, 1.006–1.020). No significant change in susceptibility was detected for K. pneumoniae (RR, 1.002; 95% CI, 0.996–1.008), and the susceptibility for E. coli continued to decline, although the decline was not as steep (RR, 0.981; 95% CI, 0.975–0.987).
A stewardship-driven FQ restriction program stopped overall declining FQ susceptibility rates for all species except E. coli. For 3 species (ie, Acinetobacter spp, E. cloacae, and P. aeruginosa), susceptibility rates improved after implementation, and this improvement has been sustained over a 10-year period.
Why do armies sometimes surrender to the enemy and sometimes fight to the bitter end? Existing research has highlighted the importance of battlefield resolve for the onset, conduct, and outcome of war, but has left these life-and-death decisions mostly unexplained. We know little about why battle-level surrender occurs, and why it stops. In this paper, we argue that surrender emerges from a collective-action problem: success in battle requires that soldiers choose to fight as a unit rather than flee, but individual decisions to fight depend on whether soldiers expect their comrades to do the same. Surrender becomes contagious across battles because soldiers take cues from what other soldiers did when they were in a similar position. Where no recent precedent exists, mass surrender is unlikely. We find empirical support for this claim using a new data set of conventional battles in all interstate wars from 1939 to 2011. These findings advance our understanding of battlefield resolve, with broader implications for the design of political-military institutions and decisions to initiate, continue, and terminate war.
This article focuses on the finite element modeling of toroidal microinductors, employing first-of-its-kind nanocomposite magnetic core material and superparamagnetic iron nanoparticles covalently cross-linked in an epoxy network. Energy loss mechanisms in existing inductor core materials are covered as well as discussions on how this novel core material eliminates them providing a path toward realizing these low form factor devices. Designs for both a 2 μH output and a 500 nH input microinductor are created via the model for a high-performance buck converter. Both modeled inductors have 50 wire turns, less than 1 cm3 form factors, less than 1 Ω AC resistance, and quality factors, Q’s, of 27 at 1 MHz. In addition, the output microinductor is calculated to have an average output power of 7 W and a power density of 3.9 kW/in3 by modeling with the 1st generation iron nanocomposite core material.
Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88) presented a critique of our recently published paper in Cell Reports entitled ‘Large-Scale Cognitive GWAS Meta-Analysis Reveals Tissue-Specific Neural Expression and Potential Nootropic Drug Targets’ (Lam et al., Cell Reports, Vol. 21, 2017, 2597–2613). Specifically, Hill offered several interrelated comments suggesting potential problems with our use of a new analytic method called Multi-Trait Analysis of GWAS (MTAG) (Turley et al., Nature Genetics, Vol. 50, 2018, 229–237). In this brief article, we respond to each of these concerns. Using empirical data, we conclude that our MTAG results do not suffer from ‘inflation in the FDR [false discovery rate]’, as suggested by Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88), and are not ‘more relevant to the genetic contributions to education than they are to the genetic contributions to intelligence’.
OBJECTIVES/SPECIFIC AIMS: Traditional clinical trials typically enroll a homogenous population to test the efficacy of an intervention. Pragmatic trials deliberately enroll a more diverse population to enhance generalizability, but doing so may increase heterogeneity of treatment effect among subpopulations. For example, the effect of a treatment on an outcome may vary based on patients’ sex, comorbidities, or baseline risk of experiencing the outcome. We hypothesized that heterogeneity of treatment effect by baseline risk for the outcome could be demonstrated in a large pragmatic clinical trial. METHODS/STUDY POPULATION: We performed a prespecified secondary analysis of a recent pragmatic trial comparing balanced crystalloids Versus 0.9% saline among critically ill adults. The primary endpoint of the trial was major adverse kidney events within 30 days of ICU admission, censored at hospital discharge (MAKE30). MAKE30 is a composite outcome of all-cause mortality, new renal replacement therapy, or persistent renal dysfunction. Using a previously published model with high predictive accuracy for MAKE30 (area under the curve=0.903), we calculated the baseline risk of MAKE30 for all trial participants. We then developed a logistic regression model for MAKE30 with independent covariates of fluid group assignment, baseline risk of MAKE30 as a nonlinear continuous variable, and the interaction between group assignment and MAKE30 baseline risk. RESULTS/ANTICIPATED RESULTS: Among 15,802 patients from 5 intensive care units enrolled in the original trial, 126 had missing variables for predicted risk of MAKE30. Mean predicted risk of MAKE30 among all patients was 15.4%; median was 4.4% (interquartile range 2.2%–17.1%). Predicted risk of MAKE30 did not significantly differ between groups (p=0.61 by Mann-Whitney U-test). The incidence of MAKE30 in the trial was 14.9%, and the prediction model was well-calibrated overall (AUC=0.891). In a logistic regression model examining the interaction between group assignment and predicted risk of MAKE30, group assignment significantly affected MAKE30 (odds ratio saline:balanced 1.13, 95% CI: 1.02–1.27, p=0.02), but we observed no interaction between the effect of group assignment on MAKE30 and patients’ predicted risk of MAKE30 at baseline (p=0.66 for interaction term). DISCUSSION/SIGNIFICANCE OF IMPACT: In a large pragmatic trial demonstrating a significant difference in the primary outcome of MAKE30 between balanced crystalloids and saline, a previously published model accurately predicted MAKE30 using baseline factors. However, contrary to our hypothesis, the baseline risk of MAKE30 did not modify the effect of fluid group on the observed incidence of MAKE30. Our analysis could not account for unmeasured confounders and may be underpowered to detect a significant interaction. Our findings suggest that the impact of balanced crystalloids versus normal saline on renal outcomes in critically patients is consistent across all levels of risk.
The influence of heat treatment (homogenization) on the microstructure, mechanical behavior, and soft magnetic properties of a face-centered cubic (fcc)-based high-entropy alloy (HEA), Fe29Co28Ni29Cu7Ti7, fabricated by casting, was investigated in detail. The as-cast Fe29Co28Ni29Cu7Ti7 HEA was composed of a primary fcc phase containing coherent dispersed L12 nanoprecipitates and trace amounts of a needle-like phase. The tensile yield strength (σ0.2), ultimate strength, and total elongation of the as-cast alloy are 917 MPa, 1060 MPa, and 1.8%, respectively. Following homogenization, the alloy having a single fcc phase shows a decrease of ∼ 55% in yield strength and a decrease of ∼ 36% in ultimate strength; however, the total elongation is increased from 1.8 to 52%. Saturation magnetization (Msat) is decreased from 111.54 to 110.34 Am2/kg, by contrast, coercivity (Hc) is increased from 266.65 to 966.89 A/m. The dissolution of precipitates and grain growth are mainly responsible for the changes in magnetic properties and mechanical behavior.
Significant reductions recently seen in the size of wide-bandgap power electronics have not been accompanied by a relative decrease in the size of the corresponding magnetic components. To achieve this, a new generation of materials with high magnetic saturation and permeability are needed. Here, we develop gram-scale syntheses of superparamagnetic Fe/FexOy core–shell nanoparticles and incorporate them as the magnetic component in a strongly magnetic nanocomposite. Nanocomposites are typically formed by the organization of nanoparticles within a polymeric matrix. However, this approach can lead to high organic fractions and phase separation; reducing the performance of the resulting material. Here, we form aminated nanoparticles that are then cross-linked using epoxy chemistry. The result is a magnetic nanoparticle component that is covalently linked and well separated. By using this ‘matrix-free’ approach, we can substantially increase the magnetic nanoparticle fraction, while still maintaining good separation, leading to a superparamagnetic nanocomposite with strong magnetic properties.
A large body of research has explored opportunities to mitigate climate change in agricultural systems; however, less research has explored opportunities across the food system. Here we expand the existing research with a review of potential mitigation opportunities across the entire food system, including in pre-production, production, processing, transport, consumption and loss and waste. We detail and synthesize recent research on the topic, and explore the applicability of different climate mitigation strategies in varying country contexts with different economic and agricultural systems. Further, we highlight some potential adaptation co-benefits of food system mitigation strategies and explore the potential implications of such strategies on food systems as a whole. We suggest that a food systems research approach is greatly needed to capture such potential synergies, and highlight key areas of additional research including a greater focus on low- and middle-income countries in particular. We conclude by discussing the policy and finance opportunities needed to advance mitigation strategies in food systems.
To identify predominant dietary patterns in four African populations and examine their association with obesity.
We used data from the Africa/Harvard School of Public Health Partnership for Cohort Research and Training (PaCT) pilot study established to investigate the feasibility of a multi-country longitudinal study of non-communicable chronic disease in sub-Saharan Africa. We applied principal component analysis to dietary intake data collected from an FFQ developed for PaCT to ascertain dietary patterns in Tanzania, South Africa, and peri-urban and rural Uganda. The sample consisted of 444 women and 294 men.
We identified two dietary patterns: the Mixed Diet pattern characterized by high intakes of unprocessed foods such as vegetables and fresh fish, but also cold cuts and refined grains; and the Processed Diet pattern characterized by high intakes of salad dressing, cold cuts and sweets. Women in the highest tertile of the Processed Diet pattern score were 3·00 times more likely to be overweight (95 % CI 1·66, 5·45; prevalence=74 %) and 4·24 times more likely to be obese (95 % CI 2·23, 8·05; prevalence=44 %) than women in this pattern’s lowest tertile (both P<0·0001; prevalence=47 and 14 %, respectively). We found similarly strong associations in men. There was no association between the Mixed Diet pattern and overweight or obesity.
We identified two major dietary patterns in several African populations, a Mixed Diet pattern and a Processed Diet pattern. The Processed Diet pattern was associated with obesity.
Despite lessons learned from the recent Ebola epidemic, attempts to survey and determine non-health care worker, industry-specific needs to address highly infectious diseases have been minimal. The aircraft rescue and fire fighting (ARFF) industry is often overlooked in highly infectious disease training and education, even though it is critical to their field due to elevated occupational exposure risk during their operations.
Supervisors perceived Frontline respondents to be more willing and comfortable to encounter potential highly infectious disease scenarios than the Frontline indicated. More than one-third of respondents incorrectly marked transmission routes of viral hemorrhagic fevers. There were discrepancies in self-reports on the existence of highly infectious disease orientation and skills demonstration, employee resources, and personal protective equipment policies, with a range of 7.5%-24.0% more Supervisors than Frontline respondents marking activities as conducted.
There are deficits in highly infectious disease knowledge, skills, and abilities among ARFF members that must be addressed to enhance member safety, health, and well-being. (Disaster Med Public Health Preparedness. 2018;12:675-679)