Using a novel iterative structure factor retrieval algorithm, here I show that electron density can be directly calculated from solution scattering data without modeling. The algorithm was validated ...with experimental data from 12 different biological macromolecules. This approach avoids many of the assumptions limiting the resolution and accuracy of modeling algorithms by explicitly calculating electron density. This algorithm can be applied to a wide variety of molecular systems.
The emergence of a pandemic affecting the respiratory system can result in a significant demand for face masks. This includes the use of cloth masks by large sections of the public, as can be seen ...during the current global spread of COVID-19. However, there is limited knowledge available on the performance of various commonly available fabrics used in cloth masks. Importantly, there is a need to evaluate filtration efficiencies as a function of aerosol particulate sizes in the 10 nm to 10 μm range, which is particularly relevant for respiratory virus transmission. We have carried out these studies for several common fabrics including cotton, silk, chiffon, flannel, various synthetics, and their combinations. Although the filtration efficiencies for various fabrics when a single layer was used ranged from 5 to 80% and 5 to 95% for particle sizes of <300 nm and >300 nm, respectively, the efficiencies improved when multiple layers were used and when using a specific combination of different fabrics. Filtration efficiencies of the hybrids (such as cotton–silk, cotton–chiffon, cotton–flannel) was >80% (for particles <300 nm) and >90% (for particles >300 nm). We speculate that the enhanced performance of the hybrids is likely due to the combined effect of mechanical and electrostatic-based filtration. Cotton, the most widely used material for cloth masks performs better at higher weave densities (i.e., thread count) and can make a significant difference in filtration efficiencies. Our studies also imply that gaps (as caused by an improper fit of the mask) can result in over a 60% decrease in the filtration efficiency, implying the need for future cloth mask design studies to take into account issues of “fit” and leakage, while allowing the exhaled air to vent efficiently. Overall, we find that combinations of various commonly available fabrics used in cloth masks can potentially provide significant protection against the transmission of aerosol particles.
Grant D. Stentiford, Kallaya Sritunyalucksana, Timothy W. Flegel, Bryony A. P. Williams, Boonsirm Withyachumnarnkul, Orn Itsathitphaisarn, David Bass Affiliations Pathology and Molecular Systematics ...Team, Centre for Environment, Fisheries and Aquaculture Science (Cefas), Weymouth, United Kingdom, Life Sciences, Natural History Museum, London, United KingdomCitation: Stentiford GD, Sritunyalucksana K, Flegel TW, Williams BAP, Withyachumnarnkul B, Itsathitphaisarn O, et al. ...funding support is acknowledged from the European Commission (EC) and the UK Department for Environment, Food and Rural Affairs (Defra) under contracts C6928 and FB002 (to GDS and DB); from the Royal Society under a University Research Fellowship (to BAPW); and to the Agricultural Research Development Agency (ARDA) and National Research Council of Thailand (NRCT) (to KS, TWF, and OI).
Purpose
Following curative treatment for localised renal cell carcinoma (RCC), up to 30% of patients develop tumour recurrence. Prognostic scores are essential to guide individualised surveillance ...protocols, patient counselling and potentially in the future to guide adjuvant therapy. In metastatic RCC, prognostic scores are routinely used for treatment selection in clinical practice as well as in all major trials.
Methods
We performed a literature review on the current evidence based on prognostic factors and models for localised and metastatic RCC.
Results
A number of prognostic factors have been identified, of which tumour node metastasis classification remains the most important. Multiple prognostic models and nomograms have been developed for localised disease, based on a combination of tumour stage, grade, subtype, clinical features, and performance status. However, there is poor level of evidence for their routine use. Prognostic scores for patients with metastatic RCC receiving targeted treatments are used routinely, but have limited accuracy. Molecular markers can improve the accuracy of established prognostic models, but frequently lack external, independent validation.
Conclusion
Several factors and models predict prognosis of localised and metastatic RCC. They represent valuable tools to provide estimates of clinically important endpoints, but their accuracy should be improved further. Validation of molecular markers is a future research priority.
To determine the efficacy and safety of low carbohydrate diets (LCDs) and very low carbohydrate diets (VLCDs) for people with type 2 diabetes.
Systematic review and meta-analysis.
Searches of ...CENTRAL, Medline, Embase, CINAHL, CAB, and grey literature sources from inception to 25 August 2020.
Randomized clinical trials evaluating LCDs (<130 g/day or <26% of a 2000 kcal/day diet) and VLCDs (<10% calories from carbohydrates) for at least 12 weeks in adults with type 2 diabetes were eligible.
Primary outcomes were remission of diabetes (HbA
<6.5% or fasting glucose <7.0 mmol/L, with or without the use of diabetes medication), weight loss, HbA
, fasting glucose, and adverse events. Secondary outcomes included health related quality of life and biochemical laboratory data. All articles and outcomes were independently screened, extracted, and assessed for risk of bias and GRADE certainty of evidence at six and 12 month follow-up. Risk estimates and 95% confidence intervals were calculated using random effects meta-analysis. Outcomes were assessed according to a priori determined minimal important differences to determine clinical importance, and heterogeneity was investigated on the basis of risk of bias and seven a priori subgroups. Any subgroup effects with a statistically significant test of interaction were subjected to a five point credibility checklist.
Searches identified 14 759 citations yielding 23 trials (1357 participants), and 40.6% of outcomes were judged to be at low risk of bias. At six months, compared with control diets, LCDs achieved higher rates of diabetes remission (defined as HbA
<6.5%) (76/133 (57%)
41/131 (31%); risk difference 0.32, 95% confidence interval 0.17 to 0.47; 8 studies, n=264, I
=58%). Conversely, smaller, non-significant effect sizes occurred when a remission definition of HbA
<6.5% without medication was used. Subgroup assessments determined as meeting credibility criteria indicated that remission with LCDs markedly decreased in studies that included patients using insulin. At 12 months, data on remission were sparse, ranging from a small effect to a trivial increased risk of diabetes. Large clinically important improvements were seen in weight loss, triglycerides, and insulin sensitivity at six months, which diminished at 12 months. On the basis of subgroup assessments deemed credible, VLCDs were less effective than less restrictive LCDs for weight loss at six months. However, this effect was explained by diet adherence. That is, among highly adherent patients on VLCDs, a clinically important reduction in weight was seen compared with studies with less adherent patients on VLCDs. Participants experienced no significant difference in quality of life at six months but did experience clinically important, but not statistically significant, worsening of quality of life and low density lipoprotein cholesterol at 12 months. Otherwise, no significant or clinically important between group differences were found in terms of adverse events or blood lipids at six and 12 months.
On the basis of moderate to low certainty evidence, patients adhering to an LCD for six months may experience remission of diabetes without adverse consequences. Limitations include continued debate around what constitutes remission of diabetes, as well as the efficacy, safety, and dietary satisfaction of longer term LCDs.
PROSPERO CRD42020161795.
This paper examines the distribution of energy efficiency incentives by race and ethnicity among residential American households based on data from the Residential Energy Consumption Survey. Across a ...variety of types of incentives, non-Hispanic White households are the mostly likely to have received an incentive relative to American Indian or Alaskan Native; Asian; Black or African American; Hispanic White; Native Hawaiian or Other Pacific Islander; or multi-racial households. I compute concentration indices to compare the degree of inequality by type of incentive. Tax credits, utility rebates, and subsidies for home energy audits have similar levels of inequality by race and ethnicity. Subsidies for efficient light bulbs have a more equal rate of uptake. The driving mechanism for these disparities appears to be that non-Hispanic White households are more likely to be homeowners, as the differences in uptake disappear in models that control for homeowner/renter status.
•Investigates relationship between race/ethnicity and energy efficiency incentives.•Analysis is based on the 2015 Residential Energy Consumption Survey.•Non-Hispanic White households are the most likely to receive an incentive.•Similar concentration indexes for tax credits, utility rebates, energy audits.•Higher non-Hispanic White homeownership rate is mechanism driving the disparities.
Molecular dynamics simulation studies of the structure and the differential capacitance (DC) for the ionic liquid (IL) N-methyl-N-propylpyrrolidinium bis(trifluoromethane)sulfonyl imide (pyr13TFSI) ...near a graphite electrode have been performed as a function temperature and electrode potential. The IL exhibits a multilayer structure that extends 20−30 Å from the electrode surface. The composition and ion orientation in the innermost layer were found to be strongly dependent on the electrode potential. While at potentials near the potential of zero charge (PZC), both cations and anions adjacent to the surface are oriented primarily perpendicular to the surface, the counterions in first layer orient increasingly parallel to the surface with increasing electrode potential. A minimum in DC observed around −1 VRPZC (potential relative to the PZC) corresponds to the point of highest density of perpendicularly aligned TFSI near the electrode. Maxima in the DC observed around +1.5 and −2.5 VRPZC are associated with the onset of “saturation”, or crowding, of the interfacial layer. The asymmetry of DC versus electrode polarity is the result of strong interactions between the fluorine of TFSI and the surface, the relatively large footprint of TFSI compared to pyr13, and the tendency of the propyl tails of pyr13 to remain adsorbed on the surface even at high positive potentials. Finally, an observed decreased DC and the disappearance of the minimum in DC near the PZC with increasing temperature are likely due to the increasing importance of entropic/excluded volume effects (interfacial crowding) with increasing temperature.
Pathways and mechanisms of endocytic recycling Grant, Barth D; Donaldson, Julie G
Nature reviews. Molecular cell biology,
200909, 2009-Sep, 2009-09-00, 20090901, Letnik:
10, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Endocytic recycling is coordinated with endocytic uptake to control the composition of the plasma membrane. Although much of our understanding of endocytic recycling has come from studies on the ...transferrin receptor, a protein internalized through clathrin-dependent endocytosis, increased interest in clathrin-independent endocytosis has led to the discovery of new endocytic recycling systems. Recent insights into the regulatory mechanisms that control endocytic recycling have focused on recycling through tubular carriers and the return to the cell surface of cargoes that enter cells through clathrin-independent mechanisms. Recent work emphasizes the importance of regulated recycling in processes as diverse as cytokinesis, cell adhesion, morphogenesis, cell fusion, learning and memory.
Research into remote sensing tools for monitoring physiological stress caused by biotic and abiotic factors is critical for maintaining healthy and highly-productive plantation forests. Significant ...research has focussed on assessing forest health using remotely sensed data from satellites and manned aircraft. Unmanned aerial vehicles (UAVs) may provide new tools for improved forest health monitoring by providing data with very high temporal and spatial resolutions. These platforms also pose unique challenges and methods for health assessments must be validated before use. In this research, we simulated a disease outbreak in mature Pinus radiata D. Don trees using targeted application of herbicide. The objective was to acquire a time-series simulated disease expression dataset to develop methods for monitoring physiological stress from a UAV platform. Time-series multi-spectral imagery was acquired using a UAV flown over a trial at regular intervals. Traditional field-based health assessments of crown health (density) and needle health (discolouration) were carried out simultaneously by experienced forest health experts. Our results showed that multi-spectral imagery collected from a UAV is useful for identifying physiological stress in mature plantation trees even during the early stages of tree stress. We found that physiological stress could be detected earliest in data from the red edge and near infra-red bands. In contrast to previous findings, red edge data did not offer earlier detection of physiological stress than the near infra-red data. A non-parametric approach was used to model physiological stress based on spectral indices and was found to provide good classification accuracy (weighted kappa=0.694). This model can be used to map physiological stress based on high-resolution multi-spectral data.
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