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Electrochemical saline water electrolysis using renewable energy as input is a highly desirable and sustainable method for the mass production of green hydrogen1-7; however, its practical viability is seriously challenged by insufficient durability because of the electrode side reactions and corrosion issues arising from the complex components of seawater. Although catalyst engineering using polyanion coatings to suppress corrosion by chloride ions or creating highly selective electrocatalysts has been extensively exploited with modest success, it is still far from satisfactory for practical applications8-14. Indirect seawater splitting by using a pre-desalination process can avoid side-reaction and corrosion problems15-21, but it requires additional energy input, making it economically less attractive. In addition, the independent bulky desalination system makes seawater electrolysis systems less flexible in terms of size. Here we propose a direct seawater electrolysis method for hydrogen production that radically addresses the side-reaction and corrosion problems. A demonstration system was stably operated at a current density of 250 milliamperes per square centimetre for over 3,200 hours under practical application conditions without failure. This strategy realizes efficient, size-flexible and scalable direct seawater electrolysis in a way similar to freshwater splitting without a notable increase in operation cost, and has high potential for practical application. Importantly, this configuration and mechanism promises further applications in simultaneous water-based effluent treatment and resource recovery and hydrogen generation in one step.
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The key challenge of spin-orbit torque applications lies in exploring an excellent spin source capable of generating out-of-plane spins while exhibiting high spin Hall conductivity. Here we combine PtTe2 for high spin conductivity and WTe2 for low crystal symmetry to satisfy the above requirements. The PtTe2/WTe2 bilayers exhibit a high in-plane spin Hall conductivity σs,y ≈ 2.32 × 105 × h/2e Ω-1 m-1 and out-of-plane spin Hall conductivity σs,z ≈ 0.25 × 105 × h/2e Ω-1 m-1, where h is the reduced Planck's constant and e is the value of the elementary charge. The out-of-plane spins in PtTe2/WTe2 bilayers enable the deterministic switching of perpendicular magnetization at room temperature without magnetic fields, and the power consumption is 67 times smaller than that of the Pt control case. The high out-of-plane spin Hall conductivity is attributed to the conversion from in-plane spin to out-of-plane spin, induced by the crystal asymmetry of WTe2. Our work establishes a low-power perpendicular magnetization manipulation based on wafer-scale two-dimensional van der Waals heterostructures.
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Electrical manipulation of magnetic states in two-dimensional ferromagnetic systems is crucial in information storage and low-dimensional spintronics. Spin-orbit torque presents a rapid and energy-efficient method for electrical control of the magnetization. In this letter, we demonstrate a wafer-scale spin-orbit torque switching of two-dimensional ferromagnetic states. Using molecular beam epitaxy, we fabricate two-dimensional heterostructures composed of low crystal-symmetry WTe2 and ferromagnet CrTe2 with perpendicular anisotropy. By utilizing out-of-plane spins generated from WTe2, we achieve field-free switching of the CrTe2 perpendicular magnetization. The threshold switching current density in CrTe2/WTe2 is 1.2 × 106 A/cm2, 20 times smaller than that of the CrTe2/Pt control sample even with an external magnetic field. In addition, the switching behavior can be modulated by external magnetic fields and crystal symmetry. Our findings demonstrate a controllable and all-electric manipulation of perpendicular magnetization in a two-dimensional ferromagnet, representing a significant advancement toward the practical implementation of low-dimensional spintronic devices.
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BACKGROUND: China's transition into an aging society is accelerated by the simultaneous decline in fertility rates and the prolonged life expectancy of older adults. The impact of widowhood, a significant stressor in old age, has emerged as a crucial factor affecting the quality of life among the elderly. METHODS: This study is based on data from the 2018 China Health and Aging Tracking Survey. Multiple linear regression models were employed to investigate the influence of widowhood on the quality of life of older adults in China. Additionally, Bootstrap mediation effects were utilized to assess the mediating role of intergenerational support, considering both financial and emotional support from children. RESULTS: The findings indicate a substantial reduction in the quality of life index among older adults following widowhood. Moreover, the impact is more pronounced among older men compared to older women. Rural older adults experience a significant decline in quality of life post-widowhood, while the effect on urban counterparts is not statistically significant. CONCLUSIONS: Intergenerational financial support was identified as a partial mediator between widowhood and the quality of life among older adults. This underscores the importance of familial financial assistance in mitigating the adverse effects of widowhood on the well-being of the elderly. These results offer valuable insights into the nuanced impact of widowhood on the quality of life among older adults in China, emphasizing the need for targeted interventions, especially in rural areas. CLINICAL TRIAL: Not applicable.
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Relação entre Gerações , Qualidade de Vida , Viuvez , Humanos , Qualidade de Vida/psicologia , Masculino , Feminino , Viuvez/psicologia , Idoso , China/epidemiologia , Idoso de 80 Anos ou mais , Apoio Social , Pessoa de Meia-IdadeRESUMO
In this paper we investigated lipid and metabolite changes in diabetic neuropathy, using untargeted lipidomics and metabolomics analyses of the spinal cords from streptozotocin-treated diabetic rats.170 metabolites and 45 lipids were dysregulated in the painful diabetic neuropathy (PDN) phase. Pathway enrichment analysis revealed perturbations in starch and sucrose, tryptophan, pyrimidine, cysteine and methionine, thiamine, tyrosine, and nucleotides. The disturbance of tyrosine, tryptophan, methionine, triacylglycerol, and phosphatidylethanolamine metabolism indicated that pathological mechanisms in the PDN involved energy metabolism, oxidative stress, and neural reparative regeneration. These revelations offered potential biomarkers for PDN and enriched the comprehension of the complex molecular mechanisms characterizing PDN, establishing a solid foundation for subsequent inquiries into neural convalescence and recovery after PDN.
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OBJECTIVE: Lactobacillus salivarius is a probiotic bacteria strain in human and animal diets. The administration of probiotics to weaned piglets may improve their growth by optimizing the gastrointestinal bacterial composition. To further investigate the effect of bacterial communication between the gastrointestinal tract and lungs on bodily immunity, we reared weaned piglets in a low-ammonia gas environment. L. salivarius was supplemented to explore its effects on pulmonary immunity and its potential for bacterial translocation. RESULTS: One hundred sixty weaned piglets were allocated to four groups: L. salivarius-supplemented, L. reuteri-supplemented, control, and antibiotic drug (aureomycin)-supplemented. The feeding duration was 28 d. The body weights of piglets administered a strain of Lactobacillus were better than those of the control (P < 0.01). The transcription level of immune factors interleukin 2 (IL-2), IL-4, interferon α (IFN-α), and tumor necrosis factor α (TNF-α) in cells of the ileum and lung was significantly higher (P < 0.01). Lung and ileal mucus tissues were isolated to sequence the bacterial composition, which suggested a higher richness in the lungs at the phylum level, which was not significant in the ileum. Functional bacteria were more abundant in the ileum and lungs. The proportion of the genera of Lactobacillus, Prevotella, Actinobacillus, and Prevotellaceae_ NK3B31_group increased in two tissues, and a lower ratio of Streptococcus, Escherichia-Shigella, and mycoplasma was detected. The correlation between the microbial genus composition and the levels of immune factors suggests that the abundance of Lactobacillus plays the same positive role in the lungs and ileum. Mycoplasmas play a negative role in ileal and pulmonary immunity. More Lactobacillus reuteri and anaerobic probiotic bacteria were detected in the lungs. CONCLUSION: The colonization of Lactobacillus salivarius and Lactobacillus reuteri in the membrane of the ileum optimized the ileal microbial composition, enrolled other probiotic bacteria translating to the lung, improved the abundance of pulmonary microbiota, and enhanced immunity after exposure to low concentrations of ammonia.
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The bird's-eye view (BEV) method, which is a vision-centric representation-based perception task, is essential and promising for future Autonomous Vehicle perception. It has advantages of fusion-friendly, intuitive, end-to-end optimization and is cheaper than LiDAR. The performance of existing BEV methods, however, would be deteriorated under the situation of a tire blow-out. This is because they quite rely on accurate camera calibration which may be disabled by noisy camera parameters during blow-out. Therefore, it is extremely unsafe to use existing BEV methods in the tire blow-out situation. In this paper, we propose a geometry-guided auto-resizable kernel transformer (GARKT) method, which is designed especially for vehicles with tire blow-out. Specifically, we establish a camera deviation model for vehicles with tire blow-out. Then we use the geometric priors to attain the prior position in perspective view with auto-resizable kernels. The resizable perception areas are encoded and flattened to generate BEV representation. GARKT predicts the nuScenes detection score (NDS) with a value of 0.439 on a newly created blow-out dataset based on nuScenes. NDS can still obtain 0.431 when the tire is completely flat, which is much more robust compared to other transformer-based BEV methods. Moreover, the GARKT method has almost real-time computing speed, with about 20.5 fps on one GPU.
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Severe acute respiratory syndrome coronavirus (SARS-CoV-1) and SARS-CoV-2 are highly pathogenic to humans and have caused pandemics in 2003 and 2019, respectively. Genetically diverse SARS-related coronaviruses (SARSr-CoVs) have been detected or isolated from bats, and some of these viruses have been demonstrated to utilize human angiotensin-converting enzyme 2 (ACE2) as a receptor and to have the potential to spill over to humans. A pan-sarbecovirus vaccine that provides protection against SARSr-CoV infection is urgently needed. In this study, we evaluated the protective efficacy of an inactivated SARS-CoV-2 vaccine against recombinant SARSr-CoVs carrying two different spike proteins (named rWIV1 and rRsSHC014S, respectively). Although serum neutralizing assays showed limited cross-reactivity between the three viruses, the inactivated SARS-CoV-2 vaccine provided full protection against SARS-CoV-2 and rWIV1 and partial protection against rRsSHC014S infection in human ACE2 transgenic mice. Passive transfer of SARS-CoV-2-vaccinated mouse sera provided low protection for rWIV1 but not for rRsSHC014S infection in human ACE2 mice. A specific cellular immune response induced by WIV1 membrane protein peptides was detected in the vaccinated animals, which may explain the cross-protection of the inactivated vaccine. This study shows the possibility of developing a pan-sarbecovirus vaccine against SARSr-CoVs for future preparedness. IMPORTANCE The genetic diversity of SARSr-CoVs in wildlife and their potential risk of cross-species infection highlight the necessity of developing wide-spectrum vaccines against infection of various SARSr-CoVs. In this study, we tested the protective efficacy of the SARS-CoV-2 inactivated vaccine (IAV) against two SARSr-CoVs with different spike proteins in human ACE2 transgenic mice. We demonstrate that the SARS-CoV-2 IAV provides full protection against rWIV1 and partial protection against rRsSHC014S. The T-cell response stimulated by the M protein may account for the cross protection against heterogeneous SARSr-CoVs. Our findings suggest the feasibility of the development of pan-sarbecovirus vaccines, which can be a strategy of preparedness for future outbreaks caused by novel SARSr-CoVs from wildlife.
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Vacinas contra COVID-19 , Infecções por Coronavirus , Proteção Cruzada , Glicoproteína da Espícula de Coronavírus , Vacinas de Produtos Inativados , Enzima de Conversão de Angiotensina 2/genética , Animais , COVID-19/prevenção & controle , Vacinas contra COVID-19/imunologia , Quirópteros , Infecções por Coronavirus/imunologia , Infecções por Coronavirus/prevenção & controle , Proteção Cruzada/imunologia , Humanos , Camundongos , Camundongos Transgênicos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/metabolismo , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinas de Produtos Inativados/imunologia , Zoonoses Virais/prevenção & controleRESUMO
Co-pyrolysis biomass and alkaline metals can effectively improve the adsorption performance of heavy metals (HM). Nevertheless, the researchers have ignored the relationship between the change of alkaline metal morphology and adsorption during pyrolysis. In this article, according to control the pyrolysis time (30, 60, and 180 min) synthesized Magnesium (Mg) modified biochar (MBCX) by using MgCl2·6H2O and soybean straw under 400 °C. The sorption capacities of MBC60 and MBC180 for Pb2+/Cd2+ increased by 38.65%/213.29%, 44.57%/230.36%, and the selectivity coefficient of Pb2+/Cd2+ increased by 113.28%/209.49%, 213.58%/253.62%, respectively, compared with MBC30. Additionally, the characterization results demonstrated that MgO dominated the surface phases of MBC60 and MBC180, whereas MgCl2 dominated the surface phases of MBC30. Moreover, according to the results of DFT calculation, the adsorption energy (Eads) of MgO for Pb2+ (-0.537 eV) and Cd2+ (-0.347 eV) was lower than that of MgCl2 (Pb2+: 0.37 eV, Cd2+: -0.185 eV), so that, MBC60 and MBC180 had higher sorption capacities for Pb2+ and Cd2+ than MBC30. Therefore, this work provides a new sight to clear the mechanism for modified biochar by alkali metal oxide and practical and theoretical guidance for adsorbent preparation with high adsorption ability for HMs.
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Cádmio , Magnésio , Chumbo , Óxido de Magnésio , Adsorção , Pirólise , Carvão VegetalRESUMO
Although it plays a critical role in the photophysics and catalysis of lanthanides, spin-orbit coupling of electrons on individual lanthanide atoms in small clusters is not well understood. The major objective of this work is to probe such coupling of the praseodymium (Pr) 4f and 6s electrons in Pr2O2 and Pr2O2+. The approach combines mass-analyzed threshold ionization spectroscopy and spin-orbit multiconfiguration second-order quasi-degenerate perturbation theory. The energies of six ionization transitions are precisely measured; the adiabatic ionization energy of the neutral cluster is 38 045 (5) cm-1. Most of the electronic states involved in these transitions are identified as spin-orbit coupled states consisting of two or more electron spins. The electron configurations of these states are 4f46s2 for the neutral cluster and 4f46s for the singly charged cation, both in planar rhombus-type structures. The spin-orbit splitting due to the coupling of the electrons on the separate Pr atoms is on the order of hundreds of wavenumbers.
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This study aimed to develop a film-forming gel containing three Chinese herbal extracts, an extracted mixture of Corydalis yanhusuo, Cynanchum paniculatum and Armadillidium vulgare (Latreille) (MCCA) and evaluate its analgesic and anti-inflammatory activities. Using the Box Behnken Design, the optimal prescription for the MCCA gel was determined. The analgesic effects were tested through acid writhing and formalin pain models. while the rheumatoid arthritis model assessed the pain and anti-inflammatory effects. For the evaluation of the effect of MCCA gels on pro-inflammatory cytokines, as well, Elisa was used. Results showed that the MCCA Gel with 2% mint oil had the highest transdermal volume of 32.57±0.92µg/cm2. High doses of MCCA gel were effective in suppressing pain, with a pain inhibition rate of 54.37% during the acetic acid peristaltic test that showed pronounced inhibition in the second phase of the formalin-induced analgesia test. In the rheumatoid arthritis model, the MCCA gel reduced inflammation scores in rat feet and decreased the expressions of four inflammatory factors in serum. Generally, The MCCA gel exhibits noticeable pain-relieving and anti-inflammatory properties with high penetration with the skin.
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Analgésicos , Artrite Reumatoide , Animais , Ratos , Analgésicos/farmacologia , Analgésicos/uso terapêutico , Dor/tratamento farmacológico , Formaldeído , GéisRESUMO
OBJECTIVES: The occurrence and zoonotic potential of antimicrobial resistance (AMR) in pigs and broilers has been studied intensively in past decades. Here, we describe AMR levels of European pig and broiler farms and determine the potential risk factors. METHODS: We collected faeces from 181 pig farms and 181 broiler farms in nine European countries. Real-time quantitative PCR (qPCR) was used to quantify the relative abundance of four antimicrobial resistance genes (ARGs) [aph(3')-III, erm(B), sul2 and tet(W)] in these faeces samples. Information on antimicrobial use (AMU) and other farm characteristics was collected through a questionnaire. A mixed model using country and farm as random effects was performed to evaluate the relationship of AMR with AMU and other farm characteristics. The correlation between individual qPCR data and previously published pooled metagenomic data was evaluated. Variance component analysis was conducted to assess the variance contribution of all factors. RESULTS: The highest abundance of ARG was for tet(W) in pig faeces and erm(B) in broiler faeces. In addition to the significant positive association between corresponding ARG and AMU levels, we also found on-farm biosecurity measures were associated with relative ARG abundance in both pigs and broilers. Between-country and between-farm variation can partially be explained by AMU. Different ARG targets may have different sample size requirements to represent the overall farm level precisely. CONCLUSIONS: qPCR is an efficient tool for targeted assessment of AMR in livestock-related samples. The AMR variation between samples was mainly contributed to by between-country, between-farm and within-farm differences, and then by on-farm AMU.
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Antibacterianos , Anti-Infecciosos , Animais , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Galinhas , Farmacorresistência Bacteriana , Fazendas , Fezes , Fatores de Risco , SuínosRESUMO
BACKGROUND: Real-time quantitative PCR (qPCR) is an affordable method to quantify antimicrobial resistance gene (ARG) targets, allowing comparisons of ARG abundance along animal production chains. OBJECTIVES: We present a comparison of ARG abundance across various animal species, production environments and humans in Europe. AMR variation sources were quantified. The correlation of ARG abundance between qPCR data and previously published metagenomic data was assessed. METHODS: A cross-sectional study was conducted in nine European countries, comprising 9572 samples. qPCR was used to quantify abundance of ARGs [aph(3')-III, erm(B), sul2, tet(W)] and 16S rRNA. Variance component analysis was conducted to explore AMR variation sources. Spearman's rank correlation of ARG abundance values was evaluated between pooled qPCR data and earlier published pooled metagenomic data. RESULTS: ARG abundance varied strongly among animal species, environments and humans. This variation was dominated by between-farm variation (pigs) or within-farm variation (broilers, veal calves and turkeys). A decrease in ARG abundance along pig and broiler production chains ('farm to fork') was observed. ARG abundance was higher in farmers than in slaughterhouse workers, and lowest in control subjects. ARG abundance showed a high correlation (Spearman's ρâ>â0.7) between qPCR data and metagenomic data of pooled samples. CONCLUSIONS: qPCR analysis is a valuable tool to assess ARG abundance in a large collection of livestock-associated samples. The between-country and between-farm variation of ARG abundance could partially be explained by antimicrobial use and farm biosecurity levels. ARG abundance in human faeces was related to livestock antimicrobial resistance exposure.
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Antibacterianos , Anti-Infecciosos , Animais , Antibacterianos/farmacologia , Bovinos , Galinhas , Estudos Transversais , Farmacorresistência Bacteriana , Fezes , Genes Bacterianos , Humanos , Gado , Carne , RNA Ribossômico 16S/genética , SuínosRESUMO
BACKGROUND: Age- and sex-specific reference nomograms for intraoperative blood pressure have been published, but they do not identify harm thresholds. The authors therefore assessed the relationship between various absolute and relative characterizations of hypotension and acute kidney injury in children having noncardiac surgery. METHODS: The authors conducted a retrospective cohort study using electronic data from two tertiary care centers. They included inpatients 18 yr or younger who had noncardiac surgery with general anesthesia. Postoperative renal injury was defined using the Kidney Disease Improving Global Outcomes definitions, based on serum creatinine concentrations. The authors evaluated potential renal harm thresholds for absolute lowest intraoperative mean arterial pressure (MAP) or largest MAP reduction from baseline maintained for a cumulative period of 5 min. Separate analyses were performed in children aged 2 yr or younger, 2 to 6 yr, 6 to 12 yr, and 12 to 18 yr. RESULTS: Among 64,412 children who had noncardiac surgery, 4,506 had creatinine assessed preoperatively and postoperatively. The incidence of acute kidney injury in this population was 11% (499 of 4,506): 17% in children under 6 yr old, 11% in children 6 to 12 yr old, and 6% in adolescents, which is similar to the incidence reported in adults. There was no association between lowest cumulative MAP sustained for 5 min and postoperative kidney injury. Similarly, there was no association between largest cumulative percentage MAP reduction and postoperative kidney injury. The adjusted estimated odds for kidney injury was 0.99 (95% CI, 0.94 to 1.05) for each 5-mmHg decrease in lowest MAP and 1.00 (95% CI, 0.97 to 1.03) for each 5% decrease in largest MAP reduction from baseline. CONCLUSIONS: In distinct contrast to adults, the authors did not find any association between intraoperative hypotension and postoperative renal injury. Avoiding short periods of hypotension should not be the clinician's primary concern when trying to prevent intraoperative renal injury in pediatric patients.
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Injúria Renal Aguda/fisiopatologia , Pressão Sanguínea/fisiologia , Hipotensão/fisiopatologia , Complicações Intraoperatórias/fisiopatologia , Monitorização Intraoperatória/métodos , Injúria Renal Aguda/diagnóstico , Adolescente , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Hipotensão/diagnóstico , Lactente , Complicações Intraoperatórias/diagnóstico , Masculino , Estudos RetrospectivosRESUMO
Beer is the most widely consumed alcoholic drink in the world, but it is not suitable for patients who suffer from celiac disease (CD) because its main ingresdients, barley or wheat, contain gluten. Approximately 1% of the world's population is affected by CD, and the development of gluten-free beer is imperative. Gluten-free beers produced using alternative materials, such as rice, sorghum, maize, millet, oats, and pseudocereals (e.g., buckwheat, quinoa and Amaranth), are studied in this review that examines the effects of specific substitutions on the different characteristics of the final beer to ensure the appropriateness of their use. The use of alternatives to malt may affect the quality of gluten-free beer and result in some negative consequences. Accordingly, the influential factors are discussed in terms of the total substitution of malt with other grains in the production of beer. Research results have provided some new alternative solutions for the production of gluten-free beer, such as the use of malted grains to improve hydrolytic enzyme activity, the application of nonconventional mashing procedures involving the decoction method and extrusion cooking techniques to increase the extract yield, the use of exogenous enzymes and nitrogen supplements to improve the sugar and amino acid spectra necessary for yeast fermentation, and the application of combinations of alternative grains to improve the flavor, body and foam stability of gluten-free beers.
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Cerveja , Fagopyrum , Cerveja/análise , Fagopyrum/química , Fermentação , Glutens/análise , Plântula/químicaRESUMO
The purpose of this study was to study the genetic mechanism of low hydrocyanic acid (HCN) content. The segregation of HCN content trait in fresh stems and leaves was determined in the sorghum (Sorghum bicolor (L.) Moench)-sudangrass (Sorghum sudanense (Piper) Stapf) hybrid F2 population (N = 1200), also used to detect a quantitative trait locus (QTL) for HCN content. Our hypothesis was that the additive effect of QTL was negative, showing that QTL was associated with low HCN. In the present research, a total of 11 simple sequence repeats (SSR) polymorphic primers were screened, and four SSR markers associated with low HCN content were developed based on the bulked segregant analysis method. A high-resolution genetic linkage group of the previously known qPA7-1 locus of the low HCN trait was constructed by analyzing different populations, families, and recombinants. Then, the QTL qPA7-1 of sorghum-sudangrass hybrid was fine-mapped to a 203.6 kb region between markers SORBI4G4-120 and SORBI4G4-680, and seven candidate genes for low HCN were predicted in this region based on sequence comparison with the sorghum reference genome. According to gene annotation, the candidate genes related to low HCN content may be different from those involved in the known regulation mode of sorghum dhurrin biosynthesis and metabolism.
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Locos de Características Quantitativas , Sorghum , Grão Comestível/genética , Ligação Genética , Marcadores Genéticos , Cianeto de Hidrogênio , Sorghum/genéticaRESUMO
A dl-alanine covalently bonded giant arsenotungstate, namely, Na3Ba11H16[(AsW9O33)6{W2O5(H2O)(dl-Ala)}2{W3O6(H2O)(dl-Ala)}2{W2O5(dl-Ala)}] (1; dl-Ala = dl-alanine), has been synthesized and is composed of six [AsW9O33]9- fragments fused together via two [W2O5(H2O)(dl-Ala)]+ segments, two [W3O6(H2O)(dl-Ala)]5+ segments, and a [W2O5(dl-Ala)]+ segment. This complex represents the first carboxylate-based hybrid polyoxotungstate without the introduction of lanthanide ions. Besides, compound 1 demonstrates not only fast photochromic properties but also interesting proton conductivity properties, with an achieved conductivity of 2.830 × 10-4 S·cm-1 (65 °C, 75% relative humidity).
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Alanina , Prótons , Ácidos CarboxílicosRESUMO
Dehydrogenation and C-C bond cleavage of 1-butyne by the excited states of La and Ce atoms are investigated in laser-ablation metal molecular beams. The excited states of the metal atoms are prepared by resonant excitation, detected by resonant two-photon ionization spectroscopy, and the reaction products are monitored by photoionization time-of-flight mass spectrometry. The reactivities of La* [5d2(3F)6p (4G5/2°)] and Ce* [4f5d(3F°)6s6p(3P°) (5H5)] excited states are observed to be higher than those of the initial states of the corresponding metal atoms. The higher reactivities of the excited states are attributed to their higher energies and favorable electron configurations to form two covalent bonds of the metal-insertion intermediates. Although both excited La and Ce atoms show increased reactivities, the enhancement for Ce is much more pronounced than that of La, which cannot be explained by electron configurations alone. The larger reactivity enhancement from the initial states to the excited state of the Ce atom than that of La is due to the longer lifetime of the Ce excited state.
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BACKGROUND: The risk of myocardial injury progressively increases at intraoperative mean arterial pressures (MAPs) ≤65 mm Hg. Higher pressures might be required in chronically hypertensive patients. We aimed to test the hypothesis that the harm threshold is higher in patients with chronic hypertension than in normotensive patients. METHODS: We conducted a single-center retrospective cohort analysis of adults >45 years old who had noncardiac surgery between 2010 and 2018 and scheduled, rather than symptom-driven, postoperative troponin measurements. The MAP thresholds under which risk started to increase were compared between patients with chronic hypertension (baseline MAP ≥110 mm Hg) and normotensive patients (baseline MAP <110 mm Hg). The primary outcome was a composite of in-hospital mortality and myocardial injury within 30 days, defined by any postoperative 4th-generation troponin T measurement ≥0.03 ng/mL apparently due to cardiac ischemia. Multivariable logistic regression and moving average smoothing methods were used to evaluate confounder-adjusted associations between the composite outcome and the lowest intraoperative MAP sustained for either 5 or 10 cumulative minutes, and whether the relationship depended on baseline pressure (normotensive versus hypertensive). RESULTS: Among 4576 eligible surgeries, 2066 were assigned to the normotensive group with mean (standard deviation [SD]) baseline MAP of 100 (7) mm Hg, and 2510 were assigned to the hypertensive group with mean baseline MAP of 122 (10) mm Hg. The overall incidence of the composite outcome was 5.6% in normotensive and 6.0% in hypertensive patients ( P = .55). The relationship between intraoperative hypotension and the composite outcome was not found to depend on baseline MAP in a multivariable mixed effects logistic regression model. Furthermore, no statistical change points were found for either baseline MAP group. CONCLUSIONS: Baseline blood pressure of the hypertensive patients was only moderately increased on average, and the event rate was low. Nonetheless, we were not able to demonstrate a difference in the harm threshold between normotensive and chronically hypertensive patients. Our results do not support the theory that hypertensive patients should be kept at higher intraoperative pressures than normotensive patients.
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Traumatismos Cardíacos , Hipertensão , Hipotensão , Adulto , Estudos de Coortes , Humanos , Hipertensão/complicações , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Hipotensão/diagnóstico , Hipotensão/epidemiologia , Hipotensão/etiologia , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos RetrospectivosRESUMO
BACKGROUND: Sugammadex and neostigmine given to reverse residual neuromuscular blockade can cause side effects including bradycardia, anaphylaxis, bronchospasm, and even cardiac arrest. We tested the hypothesis that sugammadex is noninferior to neostigmine on a composite of clinically meaningful side effects, or vice versa. METHODS: We analyzed medical records of patients who had general, cardiothoracic, or pediatric surgery and were given neostigmine or sugammadex from June 2016 to December 2019. Our primary outcome was a collapsed composite of bradycardia, anaphylaxis, bronchospasm, and cardiac arrest occurring between administration of the reversal agent and departure from the operation room. We a priori restricted our analysis to side effects requiring pharmacologic treatment that were therefore presumably clinically meaningful. Sugammadex would be considered noninferior to neostigmine (or vice versa) if the odds ratio for composite of side effects did not exceed 1.2. RESULTS: Among 89,753 surgeries in 70,690 patients, 16,480 (18%) were given sugammadex and 73,273 (82%) were given neostigmine. The incidence of composite outcome was 3.4% in patients given sugammadex and 3.0% in patients given neostigmine. The most common individual side effect was bradycardia (2.4% in the sugammadex group versus 2.2% neostigmine). Noninferiority was not found, with an estimated odds ratio of 1.21 (sugammadex versus neostigmine; 95% confidence interval [CI], 1.09-1.34; noninferiority P = .57), and neostigmine was superior to sugammadex with an estimated odds ratio of 0.83 (0.74-0.92), 1-side superiority P < .001. CONCLUSIONS: The composite incidence was less with neostigmine than with sugammadex, but only by 0.4% (a negligible clinical effect). Since 250 patients would need to be given neostigmine rather than sugammadex to avoid 1 episode of a minor complication such as bradycardia or bronchospasm, we conclude that sugammadex and neostigmine are comparably safe.