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Frascati international research criteria for HIV-associated neurocognitive disorders (HAND) are controversial; some investigators have argued that Frascati criteria are too liberal, resulting in a high false positive rate. Meyer et al. recommended more conservative revisions to HAND criteria, including exploring other commonly used methodologies for neurocognitive impairment (NCI) in HIV including the global deficit score (GDS). This study compares NCI classifications by Frascati, Meyer, and GDS methods, in relation to neuroimaging markers of brain integrity in HIV.
Two hundred forty-one people living with HIV (PLWH) without current substance use disorder or severe (confounding) comorbid conditions underwent comprehensive neurocognitive testing and brain structural magnetic resonance imaging and magnetic resonance spectroscopy. Participants were classified using Frascati criteria versus Meyer criteria: concordant unimpaired [Frascati(Un)/Meyer(Un)], concordant impaired [Frascati(Imp)/Meyer(Imp)], or discordant [Frascati(Imp)/Meyer(Un)] which were impaired via Frascati criteria but unimpaired via Meyer criteria. To investigate the GDS versus Meyer criteria, the same groupings were utilized using GDS criteria instead of Frascati criteria.
When examining Frascati versus Meyer criteria, discordant Frascati(Imp)/Meyer(Un) individuals had less cortical gray matter, greater sulcal cerebrospinal fluid volume, and greater evidence of neuroinflammation (i.e., choline) than concordant Frascati(Un)/Meyer(Un) individuals. GDS versus Meyer comparisons indicated that discordant GDS(Imp)/Meyer(Un) individuals had less cortical gray matter and lower levels of energy metabolism (i.e., creatine) than concordant GDS(Un)/Meyer(Un) individuals. In both sets of analyses, the discordant group did not differ from the concordant impaired group on any neuroimaging measure.
The Meyer criteria failed to capture a substantial portion of PLWH with brain abnormalities. These findings support continued use of Frascati or GDS criteria to detect HIV-associated CNS dysfunction.
Biochar has received attention due to its potential for mitigating climate change through carbon sequestration in soil and improving soil quality and crop productivity. This study evaluated the effects of rice straw biochar (RSB) and rice husk ash (RHA) each applied at 5 Mg ha−1 and four N levels (0, 40, 80, and 120 kg ha−1) on soil fertility, growth, and yield of rice and wheat for three consecutive rice–wheat rotations. RSB significantly increased electrical conductivity, dehydrogenase activity, and P and K contents when compared to control (no amendment) up to 7.5 cm soil depth. Both RSB and RHA did not influence shoot N concentration in wheat plant but significantly increased P and K concentrations at 60 days after sowing. Grain yields of both rice and wheat were significantly higher in RSB as compared to control (no amendment) and RHA treatments. While the highest grain yields of rice and wheat were observed at 120 kg N ha−1 in RHA and no biochar-treated plots, a significant increase in grain yields was observed at 80 kg N ha−1 in RSB treatment, thereby saving 40 kg N ha−1 in each crop. Both agronomic and recovery N efficiencies in rice and wheat were significantly higher in RSB-amended soil compared to control. Significant positive correlations were observed between soil N, P, and K concentrations and total N, P, and K concentrations in aboveground biomass of wheat at 60 days after sowing. This study showed the potential benefits of applying RSB for improving soil fertility and yields of rice and wheat in a rice–wheat system.
When patients feel spiritually supported by staff, we find increased use of hospice and reduced use of aggressive treatments at end of life, yet substantial barriers to staff spiritual care provision still exist. We aimed to study these barriers in a new cultural context and analyzed a new subgroup with “unrealized potential” for improved spiritual care provision: those who are positively inclined toward spiritual care yet do not themselves provide it.
We distributed the Religion and Spirituality in Cancer Care Study via the Middle East Cancer Consortium to physicians and nurses caring for advanced cancer patients. Survey items included how often spiritual care should be provided, how often respondents themselves provide it, and perceived barriers to spiritual care provision.
We had 770 respondents (40% physicians, 60% nurses) from 14 Middle Eastern countries. The results showed that 82% of respondents think staff should provide spiritual care at least occasionally, but 44% provide spiritual care less often than they think they should. In multivariable analysis of respondents who valued spiritual care yet did not themselves provide it to their most recent patients, predictors included low personal sense of being spiritual (p < 0.001) and not having received training (p = 0.02; only 22% received training). How “developed” a country is negatively predicted spiritual care provision (p < 0.001). Self-perceived barriers were quite similar across cultures.
Significance of results
Despite relatively high levels of spiritual care provision, we see a gap between desirability and actual provision. Seeing oneself as not spiritual or only slightly spiritual is a key factor demonstrably associated with not providing spiritual care. Efforts to increase spiritual care provision should target those in favor of spiritual care provision, promoting training that helps participants consider their own spirituality and the role that it plays in their personal and professional lives.
Collision between two identical counterflowing gravity currents was studied in the laboratory with the goal of understanding the fundamental turbulent mixing physics of flow collisions in nature, for example katabatic flows and thunderstorm outflows. The ensuing turbulent mixing is a subgrid process in mesoscale forecasting models, and needs to be parameterized using eddy diffusivity. Laboratory gravity currents were generated by simultaneously removing two identical locks, located at both ends of a long rectangular tank, which separated dense and lighter water columns with free surfaces of the same depth
. The frontal velocity
and the velocity and density fields of the gravity currents were monitored using time-resolved particle image velocimetry and planar laser-induced fluorescence imaging. Ensemble averaging of identical experimental realizations was used to compute turbulence statistics, after removing inherent jitter via phase alignment of successive data realizations by iteratively maximizing the cross-correlation of each realization with the ensemble average. Four stages of flow evolution were identified: initial (independent) propagation of gravity currents, their approach while influencing one another, collision and resulting updraughts, and postcollision slumping of collided fluid. The collision stage, in turn, involved three phases, and produced the strongest turbulent mixing as quantified by the rate of change of density. Phase I spanned
, where collision produced a rising density front (interface) with strong shear and intense turbulent kinetic energy production (
is a suitably defined time coordinate such that gravity currents make the initial contact at
). In Phase II (
), the interface was flat and calm with negligible vertical velocity. Phase III (
) was characterized by slumping which led to hydraulic bores propagating away from the collision area. The measurements included root mean square turbulent velocities and their decay rates, interfacial velocity, rate of change of fluid-parcel density, and eddy diffusivity. These measures depended on the Reynolds number
, but appeared to achieve Reynolds number similarity for
. The eddy diffusivity
, space–time averaged over the spatial extent (
) and the lifetime (
) of collision, was
, with the area
of active mixing being
Using high-precision photometry from the Kepler mission, we investigate patterns of spot activity on the K1-type subgiant component of KIC 11560447, a short-period late-type eclipsing binary. We tested the validity of maximum entropy reconstructions of starspots by numerical simulations. Our procedure successfully captures up to three large spot clusters migrating in longitude. We suggest a way to measure a lower limit for stellar differential rotation, using slopes of spot patterns in the reconstructed time-longitude diagram. We find solar-like differential rotation and recurrent spot activity with a long-term trend towards a dominant axisymmetric spot distribution during the period of observations.
Ternary lead chalcogenides, such as PbSxSe1-x, offer the possibility of room-temperature infrared detection with engineered cut-off wavelengths within the important 3-5 micron mid-wave infrared (MWIR) wavelength range. We present growth and characterization of aqueous spray-deposited thin films of PbSSe. Complexing agents in the aqueous medium suppress unwanted homogeneous reactions so that growth occurs only by the heterogeneous reaction on the hydrophilic substrate. The strongly-adherent films are smooth with a mirror-like finish. The films comprise densely packed grains with tens of nm dimensions and a total film thickness of ∼400-500 nm. Measured optical constants reveal absorption out to at least 4.5 μm wavelength and a ∼0.3 eV bandgap intermediate between those of PbS and PbSe. The semiconducting films are p-type with resistivity ∼1 and 85 Ohm-cm at 300 and 80 K, respectively. Sharp x-ray diffraction peaks identify the films as Clausthalite-Galena solid-state solution with a lattice constant that indicates an even mixture of PbS and PbSe. The photoconductive response is observed at both nitrogen and room temperature up to at least 2 kHz chopping frequency.
Detrimental effects of ultraviolet (UV) light on living organisms are well understood, little is known about the effects of blue light irradiation. Although a recent study revealed that blue light caused more harmful effects on insects than UV light and blue light irradiation killed insect pests of various orders including Diptera, the effects of blue light on physiology of insects are still largely unknown. Here we studied the effects of blue light irradiation on cuticular melanin in larval and the immune response in adult stage of Bactrocera dorsalis. We also evaluated the effects of blue light exposure in larval stage on various age and mass at metamorphosis and the mediatory role of cuticular melanin in carryover effects of larval stressors across metamorphosis. We found that larvae exposed to blue light decreased melanin contents in their exoskeleton with smaller mass and delayed metamorphosis than insects reared without blue light exposure. Across metamorphosis, lower melanotic encapsulation response and higher susceptibility to Beauveria bassiana was detected in adults that had been exposed to blue light at their larval stage, thereby constituting the first evidence that blue light impaired adult immune function in B. dorsalis as a carryover effect of larval exposure.
This study describes findings from an assessment conducted to identify perceived knowledge gaps, information needs, and research priorities among state, territorial, and local public health preparedness directors and coordinators related to public health emergency preparedness and response (PHPR). The goal of the study was to gather information that would be useful for ensuring that future funding for research and evaluation targets areas most critical for advancing public health practice.
We implemented a mixed-methods approach to identify and prioritize PHPR research questions. A web survey was sent to all state, city, and territorial health agencies funded through the Public Health Emergency Preparedness (PHEP) Cooperative Agreement program and a sample of local health departments (LHDs). Three focus groups of state and local practitioners and subject matter experts from the Centers for Disease Control and Prevention (CDC) were subsequently conducted, followed by 3 meetings of an expert panel of PHPR practitioners and CDC experts to prioritize and refine the research questions.
We identified a final list of 44 research questions that were deemed by study participants as priority topics where future research can inform PHPR programs and practice. We identified differences in perceived research priorities between PHEP awardees and LHD survey respondents; the number of research questions rated as important was greater among LHDs than among PHEP awardees (75%, n=33, compared to 24%, n=15).
The research questions identified provide insight into public health practitioners’ perceived knowledge gaps and the types of information that would be most useful for informing and advancing PHPR practice. The study also points to a higher level of information need among LHDs than among PHEP awardees. These findings are important for CDC and the PHPR research community to ensure that future research studies are responsive to practitioners’ needs and provide the information required to enhance their capacity to meet the needs of the communities and jurisdictions they serve. (Disaster Med Public Health Preparedness. 2017;11:552–561)
We extend the full wavefield modeling with forward scattering theory and Volterra Renormalization to a vertically varying two-parameter (velocity and density) acoustic medium. The forward scattering series, derived by applying Born-Neumann iterative procedure to the Lippmann-Schwinger equation (LSE), is a well known tool for modeling and imaging. However, it has limited convergence properties depending on the strength of contrast between the actual and reference medium or the angle of incidence of a plane wave component. Here, we introduce the Volterra renormalization technique to the LSE. The renormalized LSE and related Neumann series are absolutely convergent for any strength of perturbation and any incidence angle. The renormalized LSE can further be separated into two sub-Volterra type integral equations, which are then solved noniteratively. We apply the approach to velocity-only, density-only, and both velocity and density perturbations. We demonstrate that this Volterra Renormalization modeling is a promising and efficient method. In addition, it can also provide insight for developing a scattering theory-based direct inversion method.
Introduction / Innovation Concept: There are numerous research studies in the medical literature, which demonstrate how the experience of a medical residency can contribute towards burnout. The escalating performance pressures and expectations during residency training have the potential to negatively impact upon physician health and clinical performance. The purpose of this prospective cohort study was to test the effectiveness of the High Performance Physician (HPP) program among General Surgery residents at the University of Manitoba with regard to burnout and clinical performance. Methods: This program was delivered over a 9-week period. All 26 residents were asked to complete the Maslach Burnout Inventory - Human Services Survey (MBI-HSS). Each resident then participated as the team leader for a 15-minute trauma resuscitation simulation. Three attending physicians from Surgery & Emergency Medicine assessed resident performance and ability to manage work-based stressors. Following the simulation, each resident received a debrief interview. Once the HPP curriculum had been completed, residents took part in a second high fidelity simulation session and again completed the MBI-HSS. Curriculum, Tool, or Material: The HPP program offered through the Department of Emergency Medicine (EM), is a performance enhancement based curriculum. It is designed to equip physicians with mental skills to help optimize focus, arousal control, stress management, communication, and teamwork. Further, to utilize these skills to cope and respond more effectively to the inherent performance pressures that may present within one’s area of specialization. Conclusion: The Emotional Exhaustion domain of the MBI-HSS demonstrated a statistically significant decrease. The other domain scores were not statistically significant. Simulation domain scores did not demonstrate a statistically significant difference in performance between the pre- and post-HPP curriculum simulation sessions. A summative content analysis of the interview data demonstrated that residents believed internal barriers to situational awareness were the most significant impact on performance. Further study is required to determine if differences are seen in long-term follow-up.
In this study, a new centrifugal instability mode, which dominates within the boundary-layer flow over a slender rotating cone in still fluid, is used for the first time to model the problem within an enforced oncoming axial flow. The resulting problem necessitates an updated similarity solution to represent the basic flow more accurately than previous studies in the literature. The new mean flow field is subsequently perturbed, leading to disturbance equations that are solved via numerical and short-wavelength asymptotic approaches, yielding favourable comparisons with existing experiments. Essentially, the boundary-layer flow undergoes competition between the streamwise flow component, due to the oncoming flow, and the rotational flow component, due to effect of the spinning cone surface, which can be described mathematically in terms of a control parameter, namely the ratio of streamwise to axial flow. For a slender cone rotating in a sufficiently strong axial flow, the instability mode breaks down into Görtler-type counter-rotating spiral vortices, governed by an underlying centrifugal mechanism, which is consistent with experimental and theoretical studies for a slender rotating cone in otherwise still fluid.
The poultry sector is an important and vibrant segment of agriculture in Pakistan with a significant contribution to the national GDP (1.3%). Commercial poultry production in Pakistan started in the 1960's and has been providing a significant portion of daily proteins to the Pakistani population ever since. During its evolution the industry enjoyed promotional policies of the Government, but has faced several challenges such as disease outbreaks and retail price fluctuations. Despite its important role in the country's economy, not a single scientific study is available on its evolutionary history. The data available in this regard are scattered and lack reliability. This review is an effort to encompass the history of the overall growth of the poultry industry in Pakistan, its present status (2012 statistics) and future directions and challenges. This article may serve as the basic source of information on Pakistan's poultry industry achievements. It will also guide poultry experts and policy makers for developing strategic planning for further growth of the industry.
Composting is the enhanced biological decomposition of organic materials in a primarily aerobic environment. During the process, microorganisms break down organic materials to stable, usable organic substances in a process which consumes oxygen and releases heat, water, and CO2. Under controlled conditions, the composting process is described in two phases, primary and secondary. Chemical and physical properties of the raw wastes affect the rate of composting. Particle size and surface area of the waste material influence the type of microorganisms involved and the degree of biological activity in the composting process. Composting allows safe disposal of birds and manure and reduces environmental degradation. Composting of poultry manure and dead birds is still a debatable topic, however, with some scientists in favour of composting due to its overwhelming advantages while others are against composting due to certain disadvantages/environmental hazards. The present article is an effort to encompass the overall composting process, its applications as well as troubleshooting various associated issues.
This paper, a report by the Clinical Governance and Audit Committee of the Scottish Otolaryngological Society, presents a consensus view of the minimal requirements for ENT clinics in National Health Service hospitals.
Results and conclusion:
The provision of adequate equipment and staff has gained increasing importance as the vast majority of ENT procedures can be safely performed in the out-patient or office setting.
Thermoelectric (TE) materials have gained renewed interests in last decades for both power generation and energy conservation from waste-heat harvesting. Research in the discovery of best TE materials such as, bulk materials, complex structures, and low dimensional play crucial role to achieve high efficiency TE materials. Wide bandgap materials like ZnO can be promising candidate for high efficiency TE power generation owing to its low-cost, nontoxicity, and stability at high temperatures. In this paper, room temperature TE properties of thin film ZnO grown by metal organic vapor deposition (MOCVD) are reported. TE properties of thin film GaN are also studied as reference to that of thin film ZnO. Moreover, high resolution x-ray diffraction (HRXRD), room temperature photoluminescence (PL) with deep ultraviolet (DUV) spectroscopy (excitation at 248nm), hall effect, and thermal gradient methods have been employed to investigate the effect of structural, optical, electrical, and thermal properties of the samples, respectively. The effect of doping concentrations and structural defects on Seebeck coefficients of thin film ZnO are systematically studied and discussed in this work.
GaN and its alloys are promising candidates for high temperature thermoelectric (TE) materials due to their high Seebeck coefficient and high thermal and mechanical stability. Moreover, these materials can overcome the toxicity concern of current Te-based TE materials, such as Bi2Te3 and PbTe. These materials have recently shown a higher Seebeck coefficient than that of SiGe in high temperature region because their large bandgap characteristic eliminates the bipolar conduction. In this study, we report the room temperature thermoelectric properties of p-type Mg doped GaN, grown by metalorganic chemical vapor deposition (MOCVD) on sapphire substrate with various carrier concentrations. Undoped and n-type GaN are also incorporated with p-type GaN films to make comparison. The structural, optical, electrical, and thermal properties of the samples were examined by X-ray diffraction, photoluminescence, van der Pauw hall-effect, and thermal gradient methods, respectively. The Seebeck coefficient ranging from 710-900µV/K at room temperature of Mg: GaN were observed, which further indicated their potential TE applications.
We present the results of a numerical simulation of the corona and wind structure of the Sun-like exoplanet-host GJ 3021 using a global magnetohydrodynamic (MHD) model. The simulation is driven by the radial component of the surface magnetic field recovered with the Zeeman Doppler Imaging (ZDI) technique. We consider two different ZDI input maps, which have similar large-scale structures but different spatial resolutions and field strengths. These maps arise from different but comparable models used to fit the observed circularly polarised spectra of the star. Our simulations show that the structure of the inner corona is consistent among the considered cases. Larger discrepancies are found in the wind structure, in particular in the radial wind speed and the Alfvén surface topology. These elements can have a significant impact on the mass loss and angular momentum loss predicted for this system and in other studies based on this numerical data-driven approach.