Background and aims The Alcohol Use Disorders Identification Test-consumption (AUDIT-c) questionnaire screens for harmful drinking using a 12-month timeframe. A score of 0 is assigned to individuals who report abstain...
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Background and aims The Alcohol Use Disorders Identification Test-consumption (AUDIT-c) questionnaire screens for harmful drinking using a 12-month timeframe. A score of 0 is assigned to individuals who report abstaining from alcohol in the past year. However, many middle-age individuals reporting current abstinence are former drinkers (FDs). Because FDs may be more genetically prone to harmful alcohol use than lifelong abstainers (LAs) and are often combined with LAs, we evaluated the impact of differentiating them on the identification of genetic association. Design and Setting The United Kingdom Biobank (UKBB) includes AUDIT-c and alcohol drinker status. Participants 131 510 Europeans, including 5135 FDs. Measurements We compared three genome-wide association (GWAS) analyses to explore the effects of removing FDs: the full AUDIT-c data, AUDIT-c data without FDs, and data from a random sample numerically matched to the data without FDs. Because prior studies show a consistent association of the ADH1B polymorphism rs1229984 with both alcohol consumption and alcohol use disorder, we compared allele frequencies for rs1229984 stratified by AUDIT-c value and FD versus LA status. Additionally, we calculated polygenic risk scores (PRS) of related diseases. Findings The rs1229984 allele frequencies among FDs were numerically comparable to those with high AUDIT-c scores and very different from those of LAs. Removing FDs from GWAS yielded a stronger association with rs1229984 (P value after removal: 1.9 x 10(-70) vs 1.7 x 10(-65) and 2.5 x 10(-62)), more statistically significant single nucleotide polymorphisms (SNPs) (after removal: 11 vs 9 and 8), and genomic loci (after removal: 11 vs 9 and 7). Additional independent SNPs were identified after removal of FDs: rs2817866 (PTGER3), rs7105867 (ANO3), and rs17601612 (DRD2). For PRS of alcohol use disorder and major depressive disorder, there are statistically significant differences between FDs and LAs. conclusions Differenti
c/Siccomposites prepared by polymer infiltration and pyrolysis (PIP) are among the most promising materials for application in ultrahigh-temperature conditions. However, the mechan-ical properties and damage mechanis...
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c/Siccomposites prepared by polymer infiltration and pyrolysis (PIP) are among the most promising materials for application in ultrahigh-temperature conditions. However, the mechan-ical properties and damage mechanisms of PIP-c/Siccomposites at different loading velocities and temperatures have not been systematically studied. In this study, in-plane compression, bending, and in-plane shear experiments were systematically performed at different loading ve-locities and temperatures in an inert atmosphere. The ultimate strengths of the PIP-c/Siccom-posite were determined under different conditions, and the failure modes were revealed. In addition, in-situ X-ray microtomography tension experiments were conducted to study the failure mechanism of the PIP-c/Siccomposite. The results showed that the ultimate strengths were considerably affected by the temperature and loading velocity, and the failure modes were dependent on experimental types. The fracture location of the PIP-c/Siccomposite is affected by the defect. And the direction of crack propagation is toward the existing cracks and voids.
Background There is paucity in the literature to predict the occurrence of Ventilator Associated Pneumonia (VAP) in patients with Traumatic Brain Injury (TBI). We aimed to build a c.5. Decision Tree (c.5 DT) machine l...
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Background There is paucity in the literature to predict the occurrence of Ventilator Associated Pneumonia (VAP) in patients with Traumatic Brain Injury (TBI). We aimed to build a c.5. Decision Tree (c.5 DT) machine learning model to predict VAP in patients with moderate to severe TBI. Methods This was a retrospective study including all adult patients who were hospitalized with TBI plus head abbreviated injury scale (AIS) >= 3 and were mechanically ventilated in a level 1 trauma center between 2014 and 2019. Results A total of 772 eligible patients were enrolled, of them 169 had VAP (22%). The c.5 DT model achieved moderate performance with 83.5% accuracy, 80.5% area under the curve, 71% precision, 86% negative predictive value, 43% sensitivity, 95% specificity and 54% F-score. Out of 24 predictors, c.5 DT identified 5 variables predicting occurrence of VAP post-moderate to severe TBI (Time from injury to emergency department arrival, blood transfusion during resuscitation, comorbidities, Injury Severity Score and pneumothorax). conclusions This study could serve as baseline for the quest of predicting VAP in patients with TBI through the utilization of c.5. DT machine learning approach. This model helps provide timely decision support to caregivers to improve patient's outcomes.
The development of low-cost single-atom electrocatalysts for oxygen reduction reaction (ORR) is highly desired but remains a grand challenge. Superior to the conventional techniques, a microwave-assisted strategy is r...
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The development of low-cost single-atom electrocatalysts for oxygen reduction reaction (ORR) is highly desired but remains a grand challenge. Superior to the conventional techniques, a microwave-assisted strategy is reported for rapid production of high-quality Fe/N/c single-atom catalysts (SAcs) with profoundly enhanced reaction rate and remarkably reduced energy consumption. The as-synthesized catalysts exhibit an excellent ORR performance with a positive half-wave potential up to 0.90 V, a high turnover frequency of 0.76 s(-1), as well as a satisfied stability with a lost half-wave potential of just 27 mV over 9000 cycles (much better than that of Pt/c with 107 mV lost) and good methanol resistance. The open-circuit voltages of as-constructed aqueous and flexible all-solid-state Zn-air batteries (ZABs) are 1.56 and 1.52 V, respectively, higher than those of 20% Pt/c-based ones (i.e., 1.43 and 1.38 V, respectively). Impressively, they afford a peak power density of 235 mW cm(-2), which exceeds that of Pt/c (i.e., 186 mW cm(-2)), and is comparable to the best ones of Fe/N/c-based ZABs ever reported.
Tuning reactive oxygen species in peroxymonosulfate (PMS) activation by the structure of catalysts has been extensively studied. But in photocatalysis, the photothermal effect is lack of attention on the alteration of...
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Tuning reactive oxygen species in peroxymonosulfate (PMS) activation by the structure of catalysts has been extensively studied. But in photocatalysis, the photothermal effect is lack of attention on the alteration of reactive species produced by PMS activation. In this work, ZnFe2O4/c photocatalyst with oxygen vacancy (ZFOv/ c) was synthesized via the calcination of bimetallic Zn/Fe-metal-organic framework. The photocatalytic per-formance of the catalyst had been studied under several conditions, and the experimental results demonstrated that the photocatalytic reaction rate constant of ZFOv/c photocatalyst without temperature control was 21.3 % higher than that under temperature control. Reactive species quenching experiments and electron paramagnetic resonance indicated that 1O2 and h+ are the primary reactive species without temperature control, while only 1O2 are the dominant reactive species under temperature control conditions. The possible activation site was speculated by in-situ Raman spectroscopy, XPS spectra and cycling experiment. This paper analyzes the reasons for photocatalysis to improve the degradation rate of pollutant from the perspective of the change of reactive species generated by photothermal effect on PMS activation, which may open up opportunities to explore the maximum utilization of sunlight in PMS activation.
Understanding the processing of limiting nutrients among organisms is an important goal of community ecology. Less known is how human disturbances may alter the stoichiometric patterns among organisms from different t...
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Understanding the processing of limiting nutrients among organisms is an important goal of community ecology. Less known is how human disturbances may alter the stoichiometric patterns among organisms from different trophic levels within communities. Here, we investigated how livestock grazing affects the c:N:P ecological stoichiometry of soils, plants (Leymus chinensis), and grasshoppers (Euchorthippus spp.) in a semi-arid grassland in northeastern china. We found that grazing significantly enhanced soil available N and leaf N content of the dominant L. chinensis grass by 15% and 20%, respectively. Grazing also reduced (soluble) c:N of L. chinensis leaves by 22%. However, grazing did not affect total c, N, or P contents nor their ratios in Euchorthippus grasshoppers. Our results reveal that the effects of grazing disturbances on elemental composition attenuated from lower to higher trophic levels. These findings support the theory that organisms from higher trophic levels have relatively stronger stoichiometric homeostasis compared to those from lower trophic levels. Moreover, grasshopper abundance dropped by 66% in the grazed areas, and they reduced the feeding time on their host L. chinensis grass by 43%, presumably to limit the intake of excess nitrogen from host plants. The energeticcosts associated with the maintenance of elemental homeostasis likely reduced grasshopper individual performance and population abundance in the grazed areas. A comprehensive investigation of stoichiometric properties of organisms across trophic levels may enable a better understanding of the nature of species interactions, and facilitate predictions of the consequences of future environmental changes for a community organization.
Ecological stoichiometry is useful for revealing the biogeochemical characteristics of flows of nutrients and energy between plant and soil, as well as the important implications behind these ecological phenomena. How...
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Ecological stoichiometry is useful for revealing the biogeochemical characteristics of flows of nutrients and energy between plant and soil, as well as the important implications behind these ecological phenomena. However, the ecological stoichiometric linkages among leaf, litter, soil, and enzymes in the natural forests of the Loess Plateau remain largely unknown. Here, leaf, litter, and soil samples were collected from four age classes of natural Pinus tabuliformis carr. (P. tabuliformis) to explore the deep linkages among these components. We measured the total carbon (c), total nitrogen (N), and total phosphorus (P) concentrations of leaf and litter, as well as the concentrations of soil organicc, total N, total P, nitrate N, ammonium N, available P, and the activities of beta-1,4-glucosidase (a c-acquiring enzyme), beta-1,4-N-acetylglucosidase (an N-acquiring enzyme), and alkaline phosphatase (a P-acquiring enzyme) in the topsoil (0-20 cm). The average leaf N:P was 6.9 indicated the growth of P. tabuliformis was constrained by N according to the relative resorption theory of nutrient limitation. The c:N, c:P, and N:P ratios in leaf, litter, and soil and the enzyme activity were not significantly different among age classes (p > 0.05). Litter c:N (43.3) was closer to the ratio of leaf c:N (48.8), whereas the litter c:P (257.7) was obviously lower than the ratio of leaf c:P (338.15). We calculated the stoichiometric homeostasis index (1/H) of leaf responses to soil elements and enzyme activities and found that the relationship between leaf c:P and soil c:P was homeostatic (p < 0.05), whereas the remaining indices showed the leaf stoichiometries were strictly homeostatic (p > 0.05). correlation analysis showed both litter c:P and N:P were positively correlated with leaf and soil c:P, while the stoichiometric ratios of soil elements and enzymes were obviously irrelevant with leaf stoichiometries (p > 0.05). Partial least squares path modeling indicated that litter
c/SiBcN composites are expected to be widely used in aerospace applications because of their excellent high-temperature stability. However, the interfacial reactions have significantly limited their practical applicat...
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c/SiBcN composites are expected to be widely used in aerospace applications because of their excellent high-temperature stability. However, the interfacial reactions have significantly limited their practical application. A pyrocarbon (Pyc) interphase can improve the interfacial reactions of c/SiBcN composites. In this study, Pyc interphases of different thicknesses (0.1 mu m, 0.25 mu m, and 0.5 mu m) were introduced via chemical vapor deposition (cVD) process. The interface bonding of c/SiBcN composites with 0.1 mu m and 0.25 mu m thick interphases was relatively weak and the composites with 0.5 mu m interphase exhibited strong interface bonding. After heat treatment at 1600 degrees c, the mechanical properties of the c/SiBcN composites with the 0.5 mu m thick interphase was maintained at 131 MPa, and it was maintained at 105 MPa even after heat treatment at 1900 degrees c, indicating their excellent high-temperature mechanical properties. In short, 0.5 mu m thick Pyc interphase can effectively improve the interfacial reaction of the c/SiBcN composites, facilitating their application in high-temperature environments.
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