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Different no-till grain production systems with Urochloa *** soil microbial community structure,biomass and activity in a tropical Ultisol

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Soil Ecology Letters 2024年第1期6卷 119-129页

作者： Matheus Emannuel Oliveira Vieira Lucas dantas Lopes France Mario Costa Viviane Talamini Edson Patto Pacheco Marcelo Ferreira Fernandes PPGAGrI Universidade Federal de SergipeAv.Marechal Rondons/n-49100-000-Sao CristovaoSEBrazil Embrapa Coastal Tablelands Av Govemador Paulo Barreto de Menezesn°3250-49025-040-AracajuSEBrazil

Integrated grain cropping systems promote soil health(SH)and *** biomass and activity(MBA)and community structure(MCS)are key to *** of maize with Urochloa pastures strongly impacts MBA and *** is more sensitive than MCS to shifts in grain cropping *** under continuous Urochloa increased microbial activity and AMF *** soils are prone to *** of conservation agricultural practices is essential to improve soil health,which is influenced by soil *** this study we analyzed shifts in microbial biomass and activity(MBA)and microbial community structure(MCS)based on fatty acid methyl esthers(FAMEs)between five no-till agricultural practices:maize monoculture(MM);maize annualy intercropped with Urochloa decumbens(M/Ud);M/Ud with soybean rotation every other year(M/Ud-S);M/Ud keeping the pasture for the next two years(M/Ud-Ud-Ud);and maize intercropped with *** keeping the pasture for the next two years(M/Ur-Ur-Ur).results indicated that MBA was affected by the inclusion of Urochloa intercropping and by rotation with *** under a longer residence time with Urochloa in the field had higherβ-glucosidase activity and soil basal respiration,indicating a greater microbial *** was less affected than MBA by the investigated cropping *** changed only in the continuous pasture systems,which were enriched in arbuscular mycorrhyzal fungi(AMF).Additionally,the continuous pasture systems had lower microbial stress ratios than the other agricultural *** sum,our study showed that utilization of Urochloa *** longer periods in no-till agricultural practices contributes to increase microbial activity,AMF abundance and decrease microbial stress *** changes are primarily beneficial for soil health.

关键词： crop-pasture integration crop rotation no-tillage soil health microbial ecology

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观察冠状动脉疾病病人心肌灌注:320-MDCT与82rb PET的比较

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国际医学放射学杂志 2018年第4期 500-500页

作者： r.n.jr dantas A.n.jr Assuncao I.A.Marques M.G.Fahel C.H.nomura L.F.r.Avila 吴迪 Computed Tomography Department Heart InstituteIn-CorUniversity of Sao Paulo Medical School

目的尽管CT多期相MPI在无创性心肌灌注成像（MPI）评估方面取得了进展,但其方案尚未与高度精确的82rb PET MPI进行比较。故本研究旨在评估82rb PET和320层CT（320-CT）MPI在疑似CAD病人中使用多期相方案的一致性。方法前瞻性纳入44例参... 详细信息

目的尽管CT多期相MPI在无创性心肌灌注成像（MPI）评估方面取得了进展,但其方案尚未与高度精确的82rb PET MPI进行比较。故本研究旨在评估82rb PET和320层CT（320-CT）MPI在疑似CAD病人中使用多期相方案的一致性。方法前瞻性纳入44例参加MPI评估并接受双嘧达莫应激82rb PET和多期相320-CT MPI（压力期间连续5次容积采集）的病人。统计分析使用r软件进行。结果总和压力评分≥4（κ=0.77,95%CI:0.55～0.98,Prb PET MPI对于评估中度危险性的可疑CAD病人,两者间存在一致性,多期相320-CT MPI方案是可行的,可诊断并且具有相对较低的辐射照射量。

关键词： PET MPI CAD rb PET

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Localized-states quantum confinement induced by roughness in CdMnTe/CdTe heterostructures grown on Si(111) substrates

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Journal of Semiconductors 2024年第9期45卷 28-35页

作者： Leonarde n.rodrigues Wesley F.Inoch Marcos L.F.Gomes Odilon D.D.Couto jr. Bráulio S.Archanjo Sukarno O.Ferreira Physics Department Federal University of ViçosaViçosa36570-900Minas GeraisBrazil Instituto de Física Gleb Wataghin Universidade Estadual de CampinasCampinas13083-859São PauloBrazil national Institute of Metrology Quality and Technology(Inmetro) Materials Metrology Division(DIMAT)Xerém2525-020Rio de JaneiroBrazil

This work shows that despite a lattice mismatch of almost 20%, CdMnTe/CdTe/CdMnTe heterostructures grown directly on Si(111) have surprisingly good optical emission properties. The investigated structures were grown by molecular beam epitaxy and characterized by scanning transmission electron microscopy, macro-and micro-photoluminescence. Low temperature macro-photoluminescence experiments indicate three emission bands which depend on the CdTe layer thickness and have different confinement characteristics. Temperature measurements reveal that the lower energy emission band (at 1.48 eV)is associated to defects and bound exciton states, while the main emission at 1.61 eV has a weak 2D character and the higher energy one at 1.71 eV has a well-defined (zero-dimensional, 0D) 0D nature. Micro-photoluminescence measurements show the existence of sharp and strongly circularly polarized (up to 40%) emission lines which can be related to the presence of Mn in the heterostructure. This result opens the possibility of producing photon sources with the typical spin control of the diluted magnetic semiconductors using the low-cost silicon technology.

关键词： CdMnTe/CdTe/CdMnTe heterostructure CdTe/CdMnTe quantum emitters quantum dot-like emission silicon(111)substrate

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Enhancement of mechanical properties of GTAW joints for ZC63 magnesium alloy by post-weld heat treatment

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Journal of Materials Science & Technology 2024年第2期169卷 251-263页

作者： Weiyang Zhou Qichi Le Ye Shi Qiyu Liao Tong Wang Qi Zou Clodualdo Aranas jr Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang 110819China Key Laboratory of Lightweight Structural Materials Liaoning ProvinceNortheastern UniversityShenyang 110819China School of Materials Science and Engineering Northeastern UniversityShenyang 110819China Department of Mechanical Engineering University of New BrunswickFrederictonE3B 5A3New BrunswickCanada

To further improve the microstructure and mechanical properties of gas tungsten arc welded(GTAW)welded joints for ZC63 magnesium alloy,post-weld heat treatment is carried *** is found that the majority of the MgZnCu phase in the fusion zone(FZ)is dissolved in theα-Mg matrix under suitable heat treatment *** remainder is diffusely distributed as rods or granules at the grain *** excessive heat treatment temperature(460℃)leads to abnormal grain growth(AGG)in the *** substructure gradient between the abnormally grown grains and the surrounding small grains pro-vides the driving force for ***,the dissolution of the MgZnCu phase weakens the hindering effect of the second phase on grain boundary migration,setting the stage for *** addition,the detri-mental impact of the continuous MgZnCu phase on the mechanical properties of the welded joint is also lessened by its *** ultimate tensile strength(UTS),yield strength(YS)and elongation(EL)of the welded joints are 255 MPa,119 MPa and 27.0%,respectively,under the post-weld heat treatment process of 440℃×12 *** welding coefficient of the welded joint reaches 97.0%,satisfying the service criteria set forth by the mechanical properties of the welded joints.

关键词： GTAW FZ Heat treatment AGG Mechanical properties

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Influence of Omega 3 Fatty Acid Supplementation on Phase Angle Values of People Living with HIV/AIDS with Lipodystrophy Secondary to Antiretroviral Therapy: A randomized Clinical Trial

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Food and nutrition Sciences 2024年第1期15卷 58-70页

作者： Thalita Bandeira dantas Alline Peralta Castro Fernando de Souza Flexa ribeiro Filho rosana Maria Feio Libonati núcleo de Medicina Tropical do Pará Programa de Pós gradua&ccedil&atildeo em Patologia das Doen&ccedilas Tropicais Universidade Federal do Pará Pará Brasil Instituto de Ciências Biológicas e da Saúde Faculdade de Medicina Universidade Federal do Pará Pará Brasil Centro de Ciências Biológicas e da Saúde Universidade Estadual do Pará Pará Brasil

Objective: The measurement of phase angles is an important monitoring parameter and supplementation with omega-3 could promote benefits by modulating the electrical potential of membranes and increasing body cell mass. This study aimed to evaluate the effectiveness of omega-3 fatty acid supplementation on the phase angle of people living with HIV/AIDS. Methods: In this study, 63 individuals of all genders who were undergoing outpatient follow-up and showed lipodystrophy due to highly active antiretroviral therapy were analyzed. Our sample consisted of two groups, one that received supplementation containing 2550 mg of omega-3/day (1080 mg of eicosapentaenoic acid and 720 mg of docosahexaenoic acid) for three months (n = 32) and another that underwent nutrition guidance (n = 31). Phase angle and body cell mass were assessed for both groups and compared at the beginning of research (T0) and after our intervention (T1) for each group separately. results: Phase angle averaged 6.45° ± 1.06 SD. The comparison between T0 and T1 showed a significant increase in phase angle and body cell mass, whereas the guidance group showed a decrease in body cell mass at T1 in relation to T0, with a significant p-value. Variance in phase angle between moments showed significant values between T0 and T1 in the supplementation group for all genders. Conclusion: Omega-3 positively modulated patients phase angle and body cell mass, but we emphasize the need for other studies that can solidify knowledge about supplementation dosage and intervention time.

关键词： HIV Lipodystrophy Omega-3 Phase Angle

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Between Quantum Mechanics and General relativity

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Journal of Modern Physics 2024年第8期15卷 1199-1228页

作者： Walter James Christensen jr. Department of Physics and Astronomy Cal Poly Pomona University Pomona USA

The origin of elementary particle mass is considered as a function of n-valued graviton quanta. To develop this concept we begin in a cold region of “empty space” comprised of only microscopic gravitons oscillating at angular frequency ω. From opposite directions enters a pair of stray protons. Upon colliding, heat and energy are released. Customarily, this phase and what follows afterward would be described by Quantum Chromodynamics (QCD). Instead, we argue for an intermediary step. One in which neighboring gravitons absorb discrete amounts of plane-wave energy. Captured by the graviton, the planewave becomes a standing wave, whereupon its electromagnetic energy densities are converted into gravitational quanta. Immediately thereafter an elementary particle is formed and emitted, having both mass and spin. From absorption to conversion to emission occurs in less than 3.7 × 10−16 s. During this basic unit of hybrid time, general relativity and quantum physics unite into a common set of physical laws. As additional stray protons collide the process continues. Over eons, vast regions of spacetime become populated with low-mass particles. These we recognize to be dark matter by its effects on large scale structures in the universe. Its counterpart, dark energy, arises when the conversion of gravitational quanta to particle emission is interrupted. This causes the gravitational quanta to be ejected. It is recognized by its large scale effects on the universe.

关键词： Dark Matter and Energy Gravitational Quanta Graviton Standing Wave Schwarzschild Metric General relativity Quantum Physics Unified Field Theory Blackholes

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Development,validation,and transportability of several machine-learned,non-exercise-based VO_(2max)prediction models for older adults

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Journal of Sport and Health Science 2024年第5期13卷 611-620页

作者： Benjamin T.Schumacher Michael J.LaMonte Andrea Z.LaCroix Eleanor M.Simonsick Steven P.Hooker Humberto Parada jr. John Bellettiere Arun Kumar Herbert Wertheim School of Public Health and Human Longevity Science University of California San DiegoLa JollaCA 92093USA Department of Epidemiology and Environmental Health School of Public Health and Health ProfessionsUniversity at BuffaloState University of New YorkBuffaloNY 14214USA Translational Gerontology Branch Intramural Research ProgramNational Institute on AgingNational Institutes of HealthBaltimoreMD 21225USA College of Health and Human Services San Diego State UniversitySan DiegoCA 92182USA Division of Epidemiology and Biostatistics School of Public HealthSan Diego State UniversitySan DiegoCA 92182USA University of California San Diego Moores Cancer Center La JollaCA 92093USA Computer Science and Engineering and Halicioglu Data Science Institute University of California San DiegoLa JollaCA 92093USA

Background:There exist few maximal oxygen uptake(VO_(2max))non-exercise-based prediction equations,fewer using machine learning(ML),and none specifically for older *** direct measurement of VO_(2max)is infeasible in large epidemiologic cohort studies,we sought to develop,validate,compare,and assess the transportability of several ML VO_(2max)prediction ***:The Baltimore Longitudinal Study of Aging(BLSA)participants with valid VO2_(max)tests were included(n=1080).Least absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine(SVM)algorithms were trained to predict VO_(2max)*** developed these algorithms for:(a)the overall BLSA,(b)by sex,(c)using all BLSA variables,and(d)variables common in aging ***,we quantified the associations between measured and predicted VO_(2max)and ***:The age was 69.0±10.4 years(mean±SD)and the measured VO_(2max)was 21.6±5.9 mL/kg/*** absolute shrinkage and selection operator,linear-and tree-boosted extreme gradient boosting,random forest,and support vector machine yielded root mean squared errors of 3.4 mL/kg/min,3.6 mL/kg/min,3.4 mL/kg/min,3.6 mL/kg/min,and 3.5 mL/kg/min,*** quartiles of measured VO_(2max)showed an inverse gradient in mortality *** VO_(2max)variables yielded similar effect estimates but were not robust to ***:Measured VO_(2max)is a strong predictor of *** ML can improve the accuracy of prediction as compared to simpler approaches but estimates of association with mortality remain sensitive to *** studies should seek to reproduce these results so that VO_(2max),an important vital sign,can be more broadly studied as a modifiable target for promoting functional resiliency and healthy aging.

关键词： Cardiorespiratory fitness Prediction algorithms Epidemiology Mortality

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Extreme drought triggers parallel shifts in wood anatomical and physiological traits in upper treeline of the Mediterranean Andes

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Ecological Processes 2024年第1期13卷 132-143页

作者： Luiz Santini jr. Dylan Craven Daigard ricardo Ortega rodriguez Manolo Trindade Quintilhan Stephanie Gibson-Carpintero Cristina Aravena Torres Fidel A.roig Ariel A.Mu?oz Alejandro Venegas-Gonzalez Hémera Centro de Observación de la Tierra Universidad Mayor GEMA Center for Genomics Ecology and Environment Universidad Mayor Data Observatory Foundation ANID Technology Center Depart-ment of Forest Sciences ESALQ-University of Sao Paulo Department of Plant Biology Institute of Biology University of Campinas Instituto de Geografía Universidad Nacional Autónoma de México (UNAM) Argentine Institute of nivology Glaciology and Environmental Sciences(IANIGLA CONICET ) Institute of Geography Pontificia Universidad Católica de Valparaíso Instituto de Ciencias Agroalimentarias Animales y Ambientales (ICA3) Universidad de O'Higgins

Background Treeline ecotones of Mediterranean ecoregions have been affected by the increasing intensity and severity of droughts. Even though the effect of droughts on forest dynamics has been widely documented, knowledge is relatively scarce of how extreme climate episodes affect the hydraulic structure and, therefore, the phys-iology of woody plants. The Mediterranean Andes have experienced an uninterrupted period of drought since 2010, including an extremely dry year in 2019 with approximately 80% rainfall deficit. Here, we investigated shifts in wood anatomical and physiological traits of Kageneckia angustifolia, an endemic treeline species, in response to this drought *** We evaluated the xylem plasticity of three K. angustifolia populations across their natural distribution(31–35° SL) based on anatomical(vessel structure and distribution) and physiological(intrinsic water-use efficiency) variables in the tree rings. We focused on the period 2000–2020 that corresponds to before the megadrought(2000–2007),(ii) megadrought(2008–2018) and(iii) hyperdrought(2019–2020). The variables were annualized and analyzed by linear mixed-effects *** Our results provide insights to the anatomical and physiological mechanisms underlying the resilience of treeline forests to persistent droughts in central Chile. We found that the extreme drought in 2019–2020 triggered shifts in vessel size and frequency that increased hydraulic safety. These significant shifts in vessel traits occurred in parallel with a decrease in pit aperture area and an increase in water-use efficiency, further increasing the resilience of K. angustifolia to extreme drought *** Our results revealed coordinated shifts in vessel size and frequency and water-use efficiency in response to the megadrought, thereby reducing vulnerability to hydraulic failure. The apparent resilience of K. angustifolia to extreme droughts suggests that this adaptation to drought stress may incre

关键词： Dendro-anatomy Kageneckia angustifolia Xylem vulnerability Drought Climate change

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Impact on Soil Organic C and Total Soil n from Cool- and Warm-Season Legumes Used in a Green Manure-Forage Cropping System

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Agricultural Sciences 2024年第3期15卷 333-357页

作者： Clark B. neely Francis M. rouquette jr. Cristine L.S. Morgan Frank M. Hons William L. rooney Gerald r. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife research Overton TX USA Chief Scientific Officer Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern US. Forage legumes contribute nitrogen (n) to cropping systems through biological n fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool-season annual forage legumes as green manure for biomass, n content, ability to enhance soil organic carbon (SOC) and soil n, and impact on post season forage grass crops. nine warm-season forage legumes (WSL) were spring planted and incorporated as green manure in the fall. Forage rye (Secale cereale L.) was planted following the incorporation of WSL treatments. Eight cool-season forage legumes (CSL) were fall planted in previously fallow plots and incorporated as green manure in late spring. Sorghum-sudangrass (Sorghum bicolor x Sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of CSL treatments. Sorghum-sudangrass was harvested in June, August and September, and treatments were evaluated for dry matter and n concentration. Soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and n were measured using combustion analysis. nylon mesh bags containing plant samples were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and n concentrations. Mungbean (Vigna radiata L. [Wilczek]) had the highest shoot biomass yield (6.24 t DM ha-1) and contributed the most total n (167 kg∙ha-1) and total C (3043 kg∙ha-1) of the WSL tested. Decomposition rate of WSL biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum L. spp. sativum), arrow leaf clover (Trifolium vesiculosum Savi.), and crimson clover (Trifolium incarnatum L.) were the most productive CSL in this trial. Austrian winter pea

关键词： Annual Legumes Soil n Soil Organic C Green Manure Deer Browse Forage Cropping Systems

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Legume Green Manure and Intercropping for High Biomass Sorghum Production

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Agricultural Sciences 2024年第6期15卷 605-621页

作者： Clark B. neely Francis M. rouquette jr. Cristine L. S. Morgan Frank M. Hons William L. rooney Gerald r. Smith Department of Soil and Crop Science Washington State University Pullman WA USA Texas A&M AgriLife research Overton TX USA Soil Health Institute Morrisville NC USA Department of Soil and Crop Science Texas A&M University College Station TX USA

Before the advent of cheap, synthetic fertilizers, legumes were commonly used as green manure crops for their ability to fix atmospheric nitrogen (n). A three-year study at Overton, TX examined legume integration into high-biomass sorghum (Sorghum bicolor L.) production systems on a Lilbert loamy fine sand recently cultivated after a fertilized bermudagrass [Cynodon dactylon (L.) Pers.] pasture. In this split-split plot design, ‘Dixie’ crimson clover (Trifolium incarnatum L.) and ‘Iron and Clay’ cowpea (Vigna unguiculata L.) were integrated into a high-biomass sorghum production system to evaluate impacts on n concentration, C concentration, and yield of high-biomass sorghum and their impacts on soil total n and soil organic carbon (SOC). Main plots were split into crimson clover green manure (CLGM) and winter fallow (FALL) followed by three sub-plots split into warm-season crop rotations: cowpea green manure (CPGM), cowpea-sorghum intercrop (CPSr), and sorghum monocrop (SOrG). Three n fertilizer treatments (0, 45, 90 kg n∙ha−1) were randomized and applied as sub-sub plots. The CLGM increased (P sorghum biomass yield (16.5 t DM∙ha−1) 28% in year three but had no effect in the first two years. The CPSr treatment reduced sorghum yield up to 62% compared to SOrG;whereas CPGM increased sorghum yield 56% and 18% the two years following cowpea incorporation. rate of n fertilizer had no effect on sorghum biomass yield. Decrease in SOC and soil n over time indicated mineralization of organic n and may explain why no n fertilizer response was observed in sorghum biomass yield. Cowpea showed strong potential as a green manure crop but proved to be too competitive for successful intercropping in high-biomass sorghum production systems.

关键词： High-Biomass Sorghum Legumes Green Manure Intercrop Cowpea Crimson Clover Soil Organic Carbon Soil nitrogen

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