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Extensive research demonstrates unequivocally that nutrition plays a fundamental role in maintaining health and preventing disease. In parallel nutrition research provides evidence that the risks and benefits of diet and lifestyle choices do not affect people equally, as people are inherently variable in their responses to nutrition and associated interventions to maintain health and prevent disease. To simplify the inherent complexity of human subjects and their nutrition, with the aim of managing expectations for dietary guidance required to ensure healthy populations and individuals, nutrition researchers often seek to group individuals based on commonly used criteria. This strategy relies on demonstrating meaningful conclusions based on comparison of group mean responses of assigned groups. Such studies are often confounded by the heterogeneous nutrition response. Commonly used criteria applied in grouping study populations and individuals to identify mechanisms and determinants of responses to nutrition often contribute to the problem of interpreting the results of group comparisons. Challenges of interpreting the group mean using diverse populations will be discussed with respect to studies in human subjects, in vivo and in vitro model systems. Future advances in nutrition research to tackle inter-individual variation require a coordinated approach from funders, learned societies, nutrition scientists, publishers and reviewers of the scientific literature. This will be essential to develop and implement improved study design, data recording, analysis and reporting to facilitate more insightful interpretation of the group mean with respect to population diversity and the heterogeneous nutrition response.
Rush skeletonweed is emerging as a regionally important weed of winter wheat production in eastern Washington. Field studies were conducted during the 2016 and 2017 crop years to evaluate several auxin herbicides applied at two seasonal timings (fall or spring) for control of rush skeletonweed in winter wheat. Clopyralid (210 g ae ha-1) provided>90% visual control of rush skeletonweed in both years of the study and aminopyralid (10 g ae ha-1) provided>80% visual control. Aminocyclopyrachlor, dicamba, and 2,4-D provided<55% control of rush skeletonweed. Season of application did not meaningfully affect efficacy of any herbicide tested. Wheat yields were reduced by 39 to 69% compared to the non-treated check when aminocyclopyrachlor was applied in the spring. Clopyralid is an effective option for control of rush skeletonweed in Pacific Northwest winter wheat.
Puumala virus (PUUV) causes many human infections in large parts of Europe and can lead to mild to moderate disease. The bank vole (Myodes glareolus) is the only reservoir of PUUV in Central Europe. A commercial PUUV rapid field test for rodents was validated for bank-vole blood samples collected in two PUUV-endemic regions in Germany (North Rhine-Westphalia and Baden-Württemberg). A comparison of the results of the rapid field test and standard ELISAs indicated a test efficacy of 93–95%, largely independent of the origin of the antigens used in the ELISA. In ELISAs, reactivity for the German PUUV strain was higher compared to the Swedish strain but not compared to the Finnish strain, which was used for the rapid field test. In conclusion, the use of the rapid field test can facilitate short-term estimation of PUUV seroprevalence in bank-vole populations in Germany and can aid in assessing human PUUV infection risk.
Empirical social science often relies on data that are not observed in the field, but are transformed into quantitative variables by expert researchers who analyze and interpret qualitative raw sources. While generally considered the most valid way to produce data, this expert-driven process is inherently difficult to replicate or to assess on grounds of reliability. Using crowd-sourcing to distribute text for reading and interpretation by massive numbers of nonexperts, we generate results comparable to those using experts to read and interpret the same texts, but do so far more quickly and flexibly. Crucially, the data we collect can be reproduced and extended transparently, making crowd-sourced datasets intrinsically reproducible. This focuses researchers’ attention on the fundamental scientific objective of specifying reliable and replicable methods for collecting the data needed, rather than on the content of any particular dataset. We also show that our approach works straightforwardly with different types of political text, written in different languages. While findings reported here concern text analysis, they have far-reaching implications for expert-generated data in the social sciences.
The main question that Firestone & Scholl (F&S) pose is whether “what and how we see is functionally independent from what and how we think, know, desire, act, and so forth” (sect. 2, para. 1). We synthesize a collection of concerns from an interdisciplinary set of coauthors regarding F&S's assumptions and appeals to intuition, resulting in their treatment of visual perception as context-free.
Adherence engineering applies human factors principles to examine non-adherence within a specific task and to guide the development of materials or equipment to increase protocol adherence and reduce human error. Central line maintenance (CLM) for intensive care unit (ICU) patients is a task through which error or non-adherence to protocols can cause central line-associated bloodstream infections (CLABSIs). We conducted an economic analysis of an adherence engineering CLM kit designed to improve the CLM task and reduce the risk of CLABSI.
We constructed a Markov model to compare the cost-effectiveness of the CLM kit, which contains each of the 27 items necessary for performing the CLM procedure, compared with the standard care procedure for CLM, in which each item for dressing maintenance is gathered separately. We estimated the model using the cost of CLABSI overall ($45,685) as well as the excess LOS (6.9 excess ICU days, 3.5 excess general ward days).
Assuming the CLM kit reduces the risk of CLABSI by 100% and 50%, this strategy was less costly (cost savings between $306 and $860) and more effective (between 0.05 and 0.13 more quality-adjusted life-years) compared with not using the pre-packaged kit. We identified threshold values for the effectiveness of the kit in reducing CLABSI for which the kit strategy was no longer less costly.
An adherence engineering–based intervention to streamline the CLM process can improve patient outcomes and lower costs. Patient safety can be improved by adopting new approaches that are based on human factors principles.
The addition of a CdMgTe (CMT) layer at the back of a CdTe solar cell should improve its performance by reflecting both photoelectrons and forward-current electrons away from the rear surface. Higher collection of photoelectrons will increase the cell’s current, and reduction of forward current will increase its voltage. To achieve electron reflection, conformal CMT layers were deposited at the back of CdTe cells, and a variety of measurements including performance curves, transmission electron microscopy, x-ray photoelectron spectroscopy, and energy-dispersive x-ray spectroscopy were performed. Oxidation of magnesium in the CMT layer was addressed by adding a CdTe capping layer. MgCl2 passivation was substituted for CdCl2 in some cases, but little difference was seen.
In August 2012, an explosive outbreak of severe lower respiratory tract infection (LRTI) due to Streptococcus pneumoniae serotype-8 occurred in a highly vaccinated elderly institutionalized population in England. Fifteen of 23 residents developed LRTI over 4 days (attack rate 65%); 11 had confirmed S. pneumoniae serotype-8 disease, and two died. Following amoxicillin chemoprophylaxis and pneumococcal polysaccharide vaccine (PPV) re-vaccination no further cases occurred in the following 2 months. No association was found between being an outbreak-associated case and age (P = 0·36), underlying comorbidities [relative risk (RR) 0·84 95% confidence interval (CI) 0·34–2·09], or prior receipt of PPV (RR 1·4, 95% CI 0·60–3·33). However, the median number of years since PPV was significantly higher for cases (n = 15, 10·2 years, range 7·3–17·9 years) than non-cases (n = 8, 7·2 years, range 6·8–12·8 years) (P = 0·045), provided evidence of waning immunity. Alternative vaccination strategies should be considered to prevent future S. pneumoniae outbreaks in institutionalized elderly populations.
Hedging against tail events in equity markets has been forcefully advocated in the aftermath of recent global financial crisis. Whether this is beneficial to long horizon investors like employees enrolled in defined contribution (DC) plans, however, has been subject to criticism. We conduct historical simulation since 1928 to examine the effectiveness of active and passive tail risk hedging using out of money put options for hypothetical equity portfolios of DC plan participants with 20 years to retirement. Our findings show that the cost of tail hedging exceeds the benefits for a majority of the plan participants during the sample period. However, for a significant number of simulations, hedging result in superior outcomes relative to an unhedged position. Active tail hedging is more effective when employees confront several panic-driven periods characterized by short and sharp market swings in the equity markets over the investment horizon. Passive hedging, on the other hand, proves beneficial when they encounter an extremely rare event like the Great Depression as equity markets go into deep and prolonged decline.
There is increasing demand for the implementation of effects-based monitoring and surveillance (EBMS) approaches in the Great Lakes Basin to complement traditional chemical monitoring. Herein, we describe an ongoing multiagency effort to develop and implement EBMS tools, particularly with regard to monitoring potentially toxic chemicals and assessing Areas of Concern (AOCs), as envisioned by the Great Lakes Restoration Initiative (GLRI). Our strategy includes use of both targeted and open-ended/discovery techniques, as appropriate to the amount of information available, to guide a priori end point and/or assay selection. Specifically, a combination of in vivo and in vitro tools is employed by using both wild and caged fish (in vivo), and a variety of receptor- and cell-based assays (in vitro). We employ a work flow that progressively emphasizes in vitro tools for long-term or high-intensity monitoring because of their greater practicality (e.g., lower cost, labor) and relying on in vivo assays for initial surveillance and verification. Our strategy takes advantage of the strengths of a diversity of tools, balancing the depth, breadth, and specificity of information they provide against their costs, transferability, and practicality. Finally, a series of illustrative scenarios is examined that align EBMS options with management goals to illustrate the adaptability and scaling of EBMS approaches and how they can be used in management decisions.
This study aimed to determine the feasibility of using likelihood of inadequate therapy (LIT), a parameter calculated by using pathogen frequency and in vitro susceptibility for determination of appropriate empiric antibiotic therapy for primary bloodstream infections. Our study demonstrates that LIT may reveal differences in traditional antibiograms.
A 2010 Report to the President from the Council of Advisors on Science and Technology calls for “research and development to create “well-designed and validated examples of comprehensive, integrated instructional materials” for K-12 education. The Center for Functional Nanoscale Materials (CFNM) at Clark Atlanta University (CAU) and the Center for Science Education at Emory University have partnered in a program that provides a collaborative experience between CAU graduate students and Atlanta area high school and middle school teachers. The partnership expands Emory’s PRISM (Problems and Research to Integrate Science and Mathematics) program, a NSF Graduate Teaching Fellows in K-12 Education (GK-12) program. We believe that personal and experiential collaboration between these stakeholders in materials education provides even more substantial and tangible benefits.
PRISM aims to stimulate reflection, by providing teachers and graduate students (PRISM Fellows) with an opportunity to lead in producing knowledge about pedagogical practice in STEM areas. By direct linkage with pedagogic theory, teaching practice can be subjected to continuous improvement, and it is anticipated that participants will catalyze change in both the educational and research communities.
CFNM/PRISM Program ensures that both categories of Fellows participate in professional development activities designed to propagate active learning pedagogies and reflective practice during an annual Summer Institute. Teachers are immersed in a content-rich nano- and materials science research environment, while the graduate fellows have the opportunity during the subsequent academic year to assist with instruction in local schools. Thirteen graduate students and seventeen teachers have participated in the CFNM/PRISM Program over the course of five years. Teams were formed that comprised a teacher, a CAU faculty researcher and a graduate student. Each team tackled a nanoscience research problem during a summer project, developed problem-based learning (PBL) and investigative case-based learning strategies that integrate grade-appropriate science and math content, and implemented the cases in middle school and high school classrooms.
The program has been preliminarily evaluated using online written attitudinal surveys and interviews with participants. Most striking among our observations is that teachers report an enhancement of their science process skills, including an increased ability to design and implement experiments for their students. Correspondingly, graduate students report a better understanding of the importance and practice of mentoring, as well as improved ability to articulate complex scientific concepts to lay audiences. Finally, since the student body at CAU and in these Atlanta area school systems is predominantly of African American heritage, the project also contributes to diversification of the Nation’s scientific enterprise.