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Taxonomic dependency and spatial heterogeneity in assembly mechanisms of bacteria across complex coastal waters

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Ecological Processes 2024年第1期13卷 80-97页

作者： Huizhen Yan Dandan Lin Gaoke Gu Yuj.e Huang Xuya Hu Zhenhao Yu Dandi Hou Demin Zhang Barbara j.campbell Kai Wang State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products School of Marine SciencesNingbo University Key Laboratory of Marine Biotechnology of Zhej.ang Province School of Marine Sciences Ningbo University Department of Biological Sciences Clemson University

Background Understanding community assembly mechanisms across taxa and space is fundamental for microbial ecology. However, the variability and determinants of assembly processes over taxa and space remain unclear. Here, we investigated taxonomic dependency and spatial heterogeneity in bacterial assembly mechanisms across coastal waters in the East China Sea using neutral and null models with customized visualization *** Overall, bacterial assembly mechanisms varied across broad taxonomic groups(phyla and proteobacterial classes) and space at the regional scale. A determinism–stochasticity balanced mechanism governed total bacterial assembly, while taxonomic dependency existed in assembly mechanisms and ecological processes. Among community ecological features, niche breadth and negative-to-positive cohesion ratio were strongly associated with the determinism-to-stochasticity ratio of bacterial groups. Bacterial assembly mechanisms commonly exhibited spatial heterogeneity, the extent and determinants of which varied across taxonomic groups. Spatial assembly of total bacteria was directly driven by many environmental factors and potential interactions between taxa, but not directly by geographic factors. Overall, the bacterial groups with higher spatial heterogeneity in assembly mechanisms were more related to environmental and/or geographic factors(except Bacteroidetes), while those with lower heterogeneity were more related to ecological *** Our results confirm the pervasiveness of taxonomic dependency and spatial heterogeneity in bacterial assembly, providing a finer understanding about regulation across complex coastal waters.

关键词： Bacterioplankton Assembly mechanism Niche breadth Null model Environmental gradient Biogeography

Editorial for the Special Issue on Emerging Technology and Advanced Application of Nondestructive Detection for Power Equipment

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Chinese j.urnal of Electrical Engineering 2024年第1期10卷 1-2页

作者： Li j. Mei H. Li S. Tianj.n University China Tsinghua Shenzhen International Graduate School China Lanzhou j.aotong University China

The rapid development of clean and renewable energy technologies represented by wind and solar energy,as well as the continuous growth of load demand,have put forward higher requirements for the safe operation of the power *** performance of power equipment based on traditional dielectric materials is often limited by various defects generated during molding,transportation,assembly,and operation,which cannot meet the reliability requirements of power systems in the new *** detection is an essential technical method in industrial development,which can detect and evaluate the defect and damage status of in-service equipment,key components,and materials without damaging the obj.ct.

关键词： service Application operation

Error field penetration in j.TEXT tokamak based on two-fluid drift-MHD model

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Chinese Physics B 2024年第4期33卷 545-551页

作者：王文徐涛张仪 the j.TEXT team State Key Laboratory of Advanced Electromagnetic Technology International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma PhysicsSchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074China

An externally generated resonant magnetic perturbation can induce complex non-ideal MHD responses in their resonant *** have studied the plasma responses using Fitzpatrick's improved two-fluid model and program *** calculated the error field penetration threshold for *** addition,we find that the island width increases slightly as the error field amplitude increases when the error field amplitude is below the critical penetration ***,the island width suddenly j.mps to a large value because the shielding effect of the plasma against the error field disappears after the *** scanning the natural mode frequency,we find that the shielding effect of the plasma decreases as the natural mode frequency ***,we obtain the m/n=2/1 penetration threshold scaling on density and temperature.

关键词： plasma responses drift-MHD model error field penetration

Otolaryngology residency program factors associated with female resident representation

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World j.urnal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 7-11页

作者： j.lia E.Canick j.mes C.campbell Charles R.Woodard Lars j.Grimm Alissa M.Collins Duke University School of Medicine DurhamNorth CarolinaUSA Department of Head and Neck Surgery&Communication Sciences Duke University School of MedicineDurhamNorth CarolinaUSA Department of Radiology Duke University School of MedicineDurhamNorth CarolinaUSA

Obj.ctive:Female representation in the field of otolaryngology is *** is the first point at which medical school graduates specialize in a chosen field and thus represents an opportunity to recruit and train more female *** study sought to identify program factors associated with greater female representation among resident ***:Departmental websites of all 124 otolaryngology residency programs in the United States and Puerto Rico were examined for a list of *** programs with a resident roster available,the genders of residents,faculty,program directors,and chairpersons were *** and city population for each program was also recorded,as was female resident *** were compared using Pearson Chi‐squared univariate ***:1,632 residents and 2,605 faculty were included in the analysis of 109 *** median female resident representation was 40%.Programs with larger faculty sizes,more female faculty,and urban location were associated with an above‐median female resident *** with a larger residency cohort approached significance regarding above‐median female resident *** female faculty representation,program director gender,chairperson gender,and US region were not associated with variation in female resident ***:Greater female otolaryngology residency representation was associated with programs having an urban location and greater numbers of female and total *** was also likely that a larger resident cohort size may affect female resident *** proportions of female faculty,program director,and chairperson gender,as well as the US region,were not associated with variation in female resident gender representation.

关键词： gender program director recruitment residency training

Evaluating the Effects of Graviton Redshift upon Spiral Galaxy Rotation Curves, Surface Brightness Magnitudes and Gravitational Lensing

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j.urnal of High Energy Physics, Gravitation and Cosmology 2024年第3期10卷 967-985页

作者： Firmin j. Oliveira East Asian Observatory James Clerk Maxwell Submillimetre Telescope Hilo USA

The effects of the gravitational redshift of gravitons upon spiral galaxy rotation energy are compared to the standard mass to light analyses in obtaining rotation curves. The derivation of the total baryonic matter compares well with the standard theory and the rotation velocity is matched to a high precision. The stellar mass distributions obtained from the fit with graviton energy loss are used to derive the surface brightness magnitudes for the galaxies, which agree well with the observed measurements. In a new field of investigation, the graviton theory is applied to the observations of gravitational lenses. The results of these applications of the theory suggest that it can augment the standard methods and may eliminate the need for dark matter.

关键词： Gravitons Gravitational Redshift Surface Brightness Gravitational Lens Lens Mass

The Regional Economic Impacts of Coal Mining: A Case Study of Signal Peak Energy

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Natural Resources 2024年第8期15卷 211-223页

作者： Timothy j. Considine School of Energy Resources University of Wyoming Laramie USA

This paper quantifies the regional economic contributions of coal exports from the US using a case study of Signal Peak Energy in Montana. Two methods of estimating economic contributions are compared, contribution and impact analysis. The latter is adopted because the industry impact analysis is more accurate, especially since it is based upon accounting records from Signal Peak. Our estimates of regional economic and fiscal impacts do not vary significantly with the price of coal because we explicitly account for swings in royalty income. Our analysis finds that Signal Peak Energy supports 678 j.bs, over $55 million in tax revenues, more than $90 million in royalties, $111.7 million in value added, and $62.3 million in labor income. Curtailing or halting Signal Peak’s coal production for environmental reasons as some environmental groups have argued would eliminate these economic contributions.

关键词： Coal Regional Economic Exports Fiscal

An Analysis of Specific Categories of Birth Defects and Developmental Disabilities for Children of Participants of the Air Force Health Study

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Open j.urnal of Epidemiology 2024年第2期14卷 312-330页

作者： George j. Knafl School of Nursing University of North Carolina at Chapel Hill Chapel Hill NC USA

Background: The Air Force Health Study collected reproductive outcomes for live-born children of male Air Force veterans of the Vietnam War. Methods: Dioxin values for participants were obtained from blood samples. Analyses were conducted of occurrence of 16 specific categories of birth defects and developmental disabilities. Children were categorized as conceived before and after the start of participants’ Vietnam War service. Children conceived before the start of Vietnam War service were treated as being conceived when their fathers had unquantifiable dioxin values. Children conceived after the start of Vietnam War service for participants with missing dioxin values were excluded from primary analyses, but were used to assess the impact of their exclusion on conclusions. Correlation between values for specific categories for multiple children fathered by the same participant was accounted for. The dose-response relationship was treated as a step function increasing for dioxin values larger than adaptively identified individual thresholds changing with the specific category. Results: For 15 of 16 specific categories, the probability of occurrence increased substantially for a sufficiently high dioxin level above identified thresholds. Exclusion of children due to missing dioxin likely did not affect these results. Conclusions: Results supported the conclusion of substantial adverse effects on a wide variety of specific categories of birth defects and developmental disabilities due to sufficiently high exposures to dioxin, a toxic contaminant of Agent Orange used for herbicide spraying in the Vietnam War. Results may hold more generally, but might also have been affected by a variety of limitations.

关键词： Agent Orange Air Force Health Study Birth Defects Developmental Disabilities Dioxin Dose-Response Relationship Vietnam War

Experimental and Analytical Study of a Single Effect Distillation Using Electrical Evaporator Powered by Solar Energy

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j.urnal of Power and Energy Engineering 2024年第8期12卷 20-29页

作者： Saeed j. Almalowi Mechanical & Manufacturing Engineering Department Jubail Industrial College The Royal Commission for Jubail and Yanbu Jubail Saudi Arabia

The experimental and analytical investigation was conducted on a solar-powered single-effect distillation (SED). The evaporator was designed to be an electrical evaporator as opposed to the steam evaporator that existed previously. Using sun-tracking solar panels, the electrical evaporator in the designed distillation unit was powered by solar energy. Approximately 20 kWh was utilized by the small-scale distillation apparatus. This type of design is mobile, so remote areas and countries with fragile economies can utilize it on a small or large scale. Utilizing the principles of energy and mass conservation, the amount of distillate water and power required for a single unit was determined, at the low salinity (2200 PPM) with fixed boiling point temperature (Tb = 75˚C), the unit performance is approx. 98.4%. The experimental results and those derived from a mathematical model were compared, and both showed strong accord. Using engineering equation solver (EES) software, a computer program was developed for this research scenario.

关键词： Distillation Single Effect Solar Potable Salt

Development of Multilayer Models of Globular Star Clusters and Study of Their Evolution

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j.urnal of Modern Physics 2024年第8期15卷 1246-1299页

作者： j.seph j. Smulsky Institute of Earths Cryosphere Tyum. SC of SB RAS Federal Research Center Tyumen Russia

Usually, models of globular star clusters are created by analyzing their luminosity and other observation parameters. The goal of this work is to create stable models of globular clusters based on the laws of mechanics. It is necessary to set the coordinates, velocities and masses of the stars so that as a result of their gravitational interaction the globular cluster is not destroyed. This is not an easy task, and it has been solved in this paper. Using an exact solution of the axisymmetric gravitational interaction of N-bodies, single-layer spherical structures were created. They are combined into multilayer models of globular clusters. An algorithm and a program for their creation is described. As a result of solving the problem of gravitational interaction of N bodies, evolution of 5-, 10-, and 15-layer structures was studied. During the inter-body interaction, there proceeds a transition from the initial specially organized structure to a structure with bodies, uniformly distributed in space. The number of inter-body collisions decreases, and the globular cluster model passes into the stable form of its existence. The collisions of bodies and the acquisition of rotational motion and thermal energy by them are considered. As a result of the passage to scaled dimensions, the results were recalculated to the conditions of globular star clusters. The periods of rotation and the temperatures of merged stars are calculated. Attention is paid to a decreased central-body mass in the analyzed models of globular star clusters.

关键词： N-Body Problem Solution Globular Star Clusters Properties