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The study examined (a) whether alcohol use subgroups could be identified among African Americans assessed from adolescence through early adulthood, and (b) whether subgroup membership was associated with the interaction between internalizing symptoms and antisocial behavior polygenic risk scores (PRSs) and environmental characteristics (i.e., parental monitoring, community disadvantage). Participants (N = 436) were initially recruited for an elementary school-based prevention trial in a Mid-Atlantic city. Youths reported on the frequency of their past year alcohol use from ages 14–26. DNA was obtained from participants at age 21. Internalizing symptoms and antisocial behavior PRSs were created based on a genome-wide association study (GWAS) conducted by Benke et al. (2014) and Tielbeek et al. (2017), respectively. Parental monitoring and community disadvantage were assessed at age 12. Four classes of past year alcohol use were identified: (a) early-onset, increasing; (b) late-onset, moderate use; (c) low steady; and (d) early-onset, decreasing. In high community disadvantaged settings, participants with a higher internalizing symptoms PRS were more likely to be in the early-onset, decreasing class than the low steady class. When exposed to elevated community disadvantage, participants with a higher antisocial behavior PRS were more likely to be in the early-onset, increasing class than the early-onset, decreasing and late-onset, moderate use classes.
A national need is to prepare for and respond to accidental or intentional disasters categorized as chemical, biological, radiological, nuclear, or explosive (CBRNE). These incidents require specific subject-matter expertise, yet have commonalities. We identify 7 core elements comprising CBRNE science that require integration for effective preparedness planning and public health and medical response and recovery. These core elements are (1) basic and clinical sciences, (2) modeling and systems management, (3) planning, (4) response and incident management, (5) recovery and resilience, (6) lessons learned, and (7) continuous improvement. A key feature is the ability of relevant subject matter experts to integrate information into response operations. We propose the CBRNE medical operations science support expert as a professional who (1) understands that CBRNE incidents require an integrated systems approach, (2) understands the key functions and contributions of CBRNE science practitioners, (3) helps direct strategic and tactical CBRNE planning and responses through first-hand experience, and (4) provides advice to senior decision-makers managing response activities. Recognition of both CBRNE science as a distinct competency and the establishment of the CBRNE medical operations science support expert informs the public of the enormous progress made, broadcasts opportunities for new talent, and enhances the sophistication and analytic expertise of senior managers planning for and responding to CBRNE incidents.
Astrophysics Telescope for Large Area Spectroscopy Probe is a concept for a National Aeronautics and Space Administration probe-class space mission that will achieve ground-breaking science in the fields of galaxy evolution, cosmology, Milky Way, and the Solar System. It is the follow-up space mission to Wide Field Infrared Survey Telescope (WFIRST), boosting its scientific return by obtaining deep 1–4 μm slit spectroscopy for ∼70% of all galaxies imaged by the ∼2 000 deg2 WFIRST High Latitude Survey at z > 0.5. Astrophysics Telescope for Large Area Spectroscopy will measure accurate and precise redshifts for ∼200 M galaxies out to z < 7, and deliver spectra that enable a wide range of diagnostic studies of the physical properties of galaxies over most of cosmic history. Astrophysics Telescope for Large Area Spectroscopy Probe and WFIRST together will produce a 3D map of the Universe over 2 000 deg2, the definitive data sets for studying galaxy evolution, probing dark matter, dark energy and modifications of General Relativity, and quantifying the 3D structure and stellar content of the Milky Way. Astrophysics Telescope for Large Area Spectroscopy Probe science spans four broad categories: (1) Revolutionising galaxy evolution studies by tracing the relation between galaxies and dark matter from galaxy groups to cosmic voids and filaments, from the epoch of reionisation through the peak era of galaxy assembly; (2) Opening a new window into the dark Universe by weighing the dark matter filaments using 3D weak lensing with spectroscopic redshifts, and obtaining definitive measurements of dark energy and modification of General Relativity using galaxy clustering; (3) Probing the Milky Way’s dust-enshrouded regions, reaching the far side of our Galaxy; and (4) Exploring the formation history of the outer Solar System by characterising Kuiper Belt Objects. Astrophysics Telescope for Large Area Spectroscopy Probe is a 1.5 m telescope with a field of view of 0.4 deg2, and uses digital micro-mirror devices as slit selectors. It has a spectroscopic resolution of R = 1 000, and a wavelength range of 1–4 μm. The lack of slit spectroscopy from space over a wide field of view is the obvious gap in current and planned future space missions; Astrophysics Telescope for Large Area Spectroscopy fills this big gap with an unprecedented spectroscopic capability based on digital micro-mirror devices (with an estimated spectroscopic multiplex factor greater than 5 000). Astrophysics Telescope for Large Area Spectroscopy is designed to fit within the National Aeronautics and Space Administration probe-class space mission cost envelope; it has a single instrument, a telescope aperture that allows for a lighter launch vehicle, and mature technology (we have identified a path for digital micro-mirror devices to reach Technology Readiness Level 6 within 2 yr). Astrophysics Telescope for Large Area Spectroscopy Probe will lead to transformative science over the entire range of astrophysics: from galaxy evolution to the dark Universe, from Solar System objects to the dusty regions of the Milky Way.
A lasting legacy of the International Polar Year (IPY) 2007–2008 was the promotion of the Permafrost Young Researchers Network (PYRN), initially an IPY outreach and education activity by the International Permafrost Association (IPA). With the momentum of IPY, PYRN developed into a thriving network that still connects young permafrost scientists, engineers, and researchers from other disciplines. This research note summarises (1) PYRN’s development since 2005 and the IPY’s role, (2) the first 2015 PYRN census and survey results, and (3) PYRN’s future plans to improve international and interdisciplinary exchange between young researchers. The review concludes that PYRN is an established network within the polar research community that has continually developed since 2005. PYRN’s successful activities were largely fostered by IPY. With >200 of the 1200 registered members active and engaged, PYRN is capitalising on the availability of social media tools and rising to meet environmental challenges while maintaining its role as a successful network honouring the legacy of IPY.
The aim of this study was to perform a systematic review and meta-analysis of the diagnostic accuracy of a point-of-care ultrasound exam for undifferentiated shock in patients presenting to the emergency department.
Ovid MEDLINE, Scopus, Cochrane Central Register of Controlled Trials, and research meeting abstracts were searched from 1966 to June 2018 for relevant studies. QUADAS-2 was used to assess study quality, and meta-analysis was conducted to pool performance data of individual categories of shock.
A total of 5,097 non-duplicated studies were identified, of which 58 underwent full-text review; 4 were included for analysis. Study quality by QUADAS-2 was considered overall a low risk of bias. Pooled positive likelihood ratio values ranged from 8.25 (95% CI 3.29 to 20.69) for hypovolemic shock to 40.54 (95% CI 12.06 to 136.28) for obstructive shock. Pooled negative likelihood ratio values ranged from 0.13 (95% CI 0.04 to 0.48) for obstructive shock to 0.32 (95% CI 0.16 to 0.62) for mixed-etiology shock.
The rapid ultrasound for shock and hypotension (RUSH) exam performs better when used to rule in causes of shock, rather than to definitively exclude specific etiologies. The negative likelihood ratios of the exam by subtype suggest that it most accurately rules out obstructive shock.
The fact that HTA is a value-laden process is recognized in the literature. This is one of the reasons for promoting a better integration of ethics in HTA processes. Although what is meant by value-judgment (VJ) and how it can be used in HTA is not clear for some authors; others have proposed the elicitation of implicit VJs, to make them more explicit, as one way for clarifying the role ethics may play in HTA. In order to clarify what a VJ is, a conceptual analysis is needed to distinguish it from a factual-judgment and see how they diverge on certain aspects and converge on others.
The distinction between VJs and factual-judgments was debated in the fifties. At the core of the philosophy of language was a distinction between factual-scientific assertions about facts, considered objective, and VJs on what is right/wrong-good/bad, considered subjective. In speech-act theory these distinctions were treated as two different operations: assertive and evaluative. A conceptual analysis of VJs, considering them as specific speech-acts, was used for clarifying/deciphering the role of VJs in HTA.
VJs are intrinsically embedded in decision-making since they are the reasons justifying decisions. This is why implicit VJs can be identified at every decision-step in the HTA process. Assessment is usually considered objective while appraisal seems subjective. Since VJs are entrenched in the decisions taken throughout the assessment process, the results are not completely objective. Ethical analysis also distinguishes two types of VJs, those based on normative criteria and those based on various degrees of value actualization. Furthermore, since evaluation requires criteria based on a rational process, VJs are not totally subjective.
Elicitation of VJs in HTA is one way of integrating ethics in HTA and offers decision-makers a more thorough picture of the ethical issues involved in their decision.
Eliciting implicit value-judgments (VJs) in the HTA process is one way of integrating ethics in HTA since the latter is recognized as a value-laden process. An analysis of the diversity of opinions on implicit VJs in HTA and of their role, highlights the connection there exists between VJs and the different decisions involved in the whole HTA process. Such a link is corroborated by a conceptual analysis of VJ using a speech-act philosophical approach grounded in the philosophy of language, since VJs are linked with normative speech-acts such as commands, recommendations and advices.
We propose an analysis of the published citations mentioning VJs, extracted from our systematic review on the challenges of integrating ethics in HTA. In order to do so, those quotes were categorized in a chart, the latter of which presents: (i) the different steps of decision-making in the HTA process, (ii) the description of the implicit VJ(s) and (iii) the criteria involved. This chart was elaborated with the participation of the HTA local evaluators involved as co-investigators in our research group. The final version was discussed, debated and validated by the entire research group.
The chart shows 18 decision-making steps in the HTA process in which twenty-three implicit VJs can be observed. The range of such VJs encompasses the whole HTA process from the initial mandate to the agency presenting the decisional issues, to the dissemination of the final report. The published citations gathered for each category compile different expectations on the elicitation of the implicit VJs, thus making the latter VJs more explicit.
This chart allows a better understanding of the expectations that are at the core of the appeal for more transparency in the HTA process, since stakeholders need to understand which value-judgments the final conclusion of a report is relying on.
We maintain that political institutions’ policy objectives are best met under conditions when they are unified, and also when their administrative leadership is effective. We apply this argument to the understanding of how unified Democratic and Republican governments in the American states have influenced the incomes of affluent citizens. We find that affluent income gains occur under unified Republican state governments when compensation to executive agency heads is sufficiently high. These income gains are notable relative to both divided and unified partisan control of state governments. The evidence highlights the asymmetric role that bureaucratic leadership plays in attaining policy outcomes consistent with political institutions’ policy preferences, while underscoring the limits of electoral institutions to shape policy outcomes of their own accord. Efforts to lower the capacity of the administrative leadership constrain unified political institutions from converting their policy objectives into policy outcomes.
Increasing evidence indicates that gut microbiota may influence colorectal cancer risk. Diet, particularly fibre intake, may modify gut microbiota composition, which may affect cancer risk. We investigated the relationship between dietary fibre intake and gut microbiota in adults. Using 16S rRNA gene sequencing, we assessed gut microbiota in faecal samples from 151 adults in two independent study populations: National Cancer Institute (NCI), n 75, and New York University (NYU), n 76. We calculated energy-adjusted fibre intake based on FFQ. For each study population with adjustment for age, sex, race, BMI and smoking, we evaluated the relationship between fibre intake and gut microbiota community composition and taxon abundance. Total fibre intake was significantly associated with overall microbial community composition in NYU (P=0·008) but not in NCI (P=0·81). In a meta-analysis of both study populations, higher fibre intake tended to be associated with genera of class Clostridia, including higher abundance of SMB53 (fold change (FC)=1·04, P=0·04), Lachnospira (FC=1·03, P=0·05) and Faecalibacterium (FC=1·03, P=0·06), and lower abundance of Actinomyces (FC=0·95, P=0·002), Odoribacter (FC=0·95, P=0·03) and Oscillospira (FC=0·96, P=0·06). A species-level meta-analysis showed that higher fibre intake was marginally associated with greater abundance of Faecalibacterium prausnitzii (FC=1·03, P=0·07) and lower abundance of Eubacterium dolichum (FC=0·96, P=0·04) and Bacteroides uniformis (FC=0·97, P=0·05). Thus, dietary fibre intake may impact gut microbiota composition, particularly class Clostridia, and may favour putatively beneficial bacteria such as F. prausnitzii. These findings warrant further understanding of diet–microbiota relationships for future development of colorectal cancer prevention strategies.
Integration of ethics into health technology assessment (HTA) remains challenging for HTA practitioners. We conducted a systematic review on social and methodological issues related to ethical analysis in HTA. We examined: (1) reasons for integrating ethics (social needs); (2) obstacles to ethical integration; (3) concepts and processes deployed in ethical evaluation (more specifically value judgments) and critical analyses of formal experimentations of ethical evaluation in HTA.
Search criteria included “ethic,” “technology assessment,” and “HTA”. The literature search was done in Medline/Ovid, SCOPUS, CINAHL, PsycINFO, and the international HTA Database. Screening of citations, full-text screening, and data extraction were performed by two subgroups of two independent reviewers. Data extracted from articles were grouped into categories using a general inductive method.
A list of 1,646 citations remained after the removal of duplicates. Of these, 132 were fully reviewed, yielding 67 eligible articles for analysis. The social need most often reported was to inform policy decision making. The absence of shared standard models for ethical analysis was the obstacle to integration most often mentioned. Fairness and Equity and values embedded in Principlism were the values most often mentioned in relation to ethical evaluation.
Compared with the scientific experimental paradigm, there are no settled proceedings for ethics in HTA nor consensus on the role of ethical theory and ethical expertise hindering its integration. Our findings enable us to hypothesize that there exists interdependence between the three issues studied in this work and that value judgments could be their linking concept.
To investigate which populations of patients are considered ‘vulnerable’ across varying clinical sites, and to identify the barriers encountered by these patient populations limiting optimal health.
Vulnerable patient populations encounter diverse barriers that limit their ability to successfully navigate the health system, potentially resulting in poor health outcomes. Little current-day work has described types of barriers encountered by vulnerable patient populations across numerous clinical sites and settings, which is necessary to ensure health systems can begin to improve quality and disparities for all patient populations.
An inductive content analysis was performed based on field-site notes and digitally recorded telephone interviews with providers/leadership at clinics/programs related to patient- and clinic-needs from January 2014 through May 2015. Using thematic analysis with grounded theory techniques, authors identified categories and themes. In total, 30 diverse clinical sites/programs including inpatient- and outpatient-based clinics providing medicine and surgery-based services were assessed through both site visits and follow-up telephone interviews. Follow-up interviews were conducted with one individual in various positions within sites/programs, including physicians (n=15), registered nurses (n=8), clinic managers/coordinators (n=2), clinical program coordinator (n=1), and care coordinator (n=1); one participant represented three clinical sites.
In total, 30 sites/programs (n=30) received both a site visit and follow-up interview. Commonly reported vulnerable patient populations included those with multiple chronic conditions, lower socioeconomic status, patients in a specific stage in the continuum of care, and patients with over- and under-utilization of resources without a clear etiology. Themes related to barriers included systems barriers (eg, insufficiencies of care processes), clinic barriers (eg, lack of resources), patient-related barriers (eg, housing, transportation), and provider-related barriers (eg, inadequate time and knowledge).
These results provide a framework to identify systems- and clinic-related barriers that can be used in population health management strategies aimed at improving health disparities within clinically diverse sites.
This work is part of the interlaboratory collaboration to study the stability of organic solar cells containing PCDTBT polymer as a donor material. The varieties of the OPV devices with different device architectures, electrode materials, encapsulation, and device dimensions were prepared by seven research laboratories. Sets of identical devices were aged according to four different protocols: shelf lifetime, laboratory weathering under simulated illumination at ambient temperature, laboratory weathering under simulated illumination, and elevated temperature (65 °C) and daylight outdoor weathering under sunlight. The results generated in this study allow us to outline several general conclusions related to PCDTBT-based bulk heterojunction (BHJ) solar cells. The results herein reported can be considered as practical guidance for the realization of stabilization approaches in BHJ solar cells containing PCDTBT.
In this contribution, a design methodology for octave-bandwidth power amplifiers (PA) for 5G communication systems using surface mount dual-flat-no-lead packaged gallium-nitride high-electron-mobility transistor devices is presented. Systematic source- and load-pull simulations have been used to find the optimum impedances across 75% fractional bandwidth for S- (1.9–4.2 GHz) and C-band (3.8–8.4 GHz) PAs. The harmonic impact is considered to improve the output power and efficiency of the PAs. Utilizing the characteristic behavior of the transistors leads to modified optimum fundamental load impedances for the low-frequency range, which have higher gain compared with high-frequency range, and minimize the influence of the higher harmonics. Continuous wave large-signal measurements of the realized S-Band PA show a power added efficiency (PAE) of more than 40% from 1.9–4.2 GHz and a flat power gain of 11 dB while achieving a saturated output power of 10 W. The measured performance of the C-Band PA demonstrates a delivered power between 3.5 and 5 W across the frequency range of 3.8–8.4 GHz. A flat power gain of around 9 ± 0.5 dB with 26–40% PAE is achieved.
Objectives: The aim of this study was to investigate the relationship of psychological variables to cognitive performance validity test (PVT) results in mixed forensic and nonforensic clinical samples. Methods: Participants included 183 adults who underwent comprehensive neuropsychological examination. Criterion groups were formed, that is, Credible Group or Noncredible Group, based upon their performance on the Word Memory Test and other stand-alone and embedded PVT measures. Results: Multivariate logistic regression analysis identified three significant predictors of cognitive performance validity. These included two psychological constructs, for example, Cogniphobia (perception that cognitive effort will exacerbate neurological symptoms), and Symptom Identity (perception that current symptoms are the result of illness or injury), and one contextual factor (forensic). While there was no interaction between these factors, elevated scores were most often observed in the forensic sample, suggesting that these independently contributing intrinsic psychological factors are more likely to occur in a forensic environment. Conclusions: Illness perceptions were significant predictors of cognitive performance validity particularly when they reached very elevated levels. Extreme elevations were more common among participants in the forensic sample, and potential reasons for this pattern are explored. (JINS, 2018, 24, 1–11)
There is strong evidence that people born in winter and in spring have a small increased risk of schizophrenia. As this ‘season of birth’ effect underpins some of the most influential hypotheses concerning potentially modifiable risk exposures, it is important to exclude other possible explanations for the phenomenon.
Here we sought to determine whether the season of birth effect reflects gene-environment confounding rather than a pathogenic process indexing environmental exposure. We directly measured, in 136 538 participants from the UK Biobank (UKBB), the burdens of common schizophrenia risk alleles and of copy number variants known to increase the risk for the disorder, and tested whether these were correlated with a season of birth.
Neither genetic measure was associated with season or month of birth within the UKBB sample.
As our study was highly powered to detect small effects, we conclude that the season of birth effect in schizophrenia reflects a true pathogenic effect of environmental exposure.
Materials science is arguably the most important discipline in the physical sciences that should be developed in Africa given its rich resources of minerals, energy and biological diversity. Developing materials science should therefore be an important goal for Africa with important opportunities for economic benefits and quality people development. There are already many successful materials science activities that are underway in Africa. This needs to gain wider international attention and should become contact points for international collaborations. The African School for Electronic Structure Methods and Applications (ASESMA)[1,2,3,4] is one such successful initiative that has been in existence for the past decade. ASESMA has shown that it is possible to build a network across sub-Saharan Africa with world-class research with a relatively low budget. The greatest asset is the commitment of the lecturers and mentors, the team-work of the local organisers and the idealism of the participants who rank amongst the brightest of young minds from Africa, many of whom come from impoverished backgrounds but still dare to reach for the stars.