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Landau damping in a dipolar Bose–Fermi mixture in the Bose–einstein condensation(BeC) limit

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Chinese Physics B 2016年第12期25卷 367-376页

作者： S M Moniri h Yavari e Darsheshdar Department of Physics University of Isfahan

By using a mean-field approximation which describes the coupled oscillations of condensate and noncondensate atoms in the collisionless regime, Landau damping in a dilute dipolar Bose-Fermi mixture in the BeC limit where Fermi superfluid is treated as tightly bounded molecules, is investigated. In the case of a uniform quasi-two-dimensional （2D） case, the results for the Landau damping due to the Bose-Fermi interaction are obtained at low and high temperatures. It is shown that at low temperatures, the Landau damping rate is exponentially suppressed. By increasing the strength of dipolar interaction, and the energy of boson quasiparticles, Landau damping is suppressed over a broader temperature range.

关键词： Landau damping mixtures of Bose and Fermi superfluids dipole-dipole interaction

Combining slow-release fertilizer and plastic film mulching reduced the carbon footprint and enhanced maize yield on the Loess Plateau

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Journal of environmental Sciences 2025年第1期147卷 359-369页

作者： Xiaoqing han Pengfei Dang Lechen Liao Fangqi Song Miaomiao Zhang Maoxue Zhang Guoqing Li Shuyue Wen Ning Yang Xiping Pan Xiaofan Wang WenWang Xiaoliang Qin Charles O.Joseph Kadambot h.M.Siddique College of Agronomy Key Laboratory of Crop Physi-ecology and Tillage Science in Northwestern Loess PlateauNorthwest A&F UniversityYanglingShaanxi 712100China Department of Crop Sciences and Beekeeping Technology College of Agricultural Sciences and Food Technology University of Dar es SalaamMwalimu Julius Nyerere Mlimani CampusP.O.Box 35091Dar es SalaamTanzania College of Life Science Yulin UniversityChongwen Road No.4YulinShaanxi719000China The UWA Institute of Agriculture and School of Agriculture&environment The University of Western AustraliaPerth WA 6001Australia

Agricultural practices significantly contribute to greenhouse gas(GhG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize *** film mulching is commonly used in the Loess Plateau *** slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop *** these techniques represents a novel agricultural approach in semi-arid ***,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research ***,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental *** results revealed that nitrogen fertilizer was the primary contributor to total GhG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.

关键词： Plastic film mulching Slow-release fertilizer Maize grain yield Carbon footprint economic benefits

Therapeutic potential of exercise-hormone irisin in Alzheimer's disease

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Neural Regeneration Research 2025年第6期20卷 1555-1564页

作者： eunhee Kim Rudolph eTanzi Se hoon Choi Genetics and Aging Research Unit MassGeneral Institute for Neurodegenerative DiseaseDepartment of NeurologyMassachusetts General HospitalHarvard Medical SchoolCharlestownMAUSA McCance Center for Brain health Massachusetts General HospitalBostonMAUSA

Irisin is a myokine that is generated by cleavage of the membrane protein fibronectin type Ⅲ domain-containing protein 5(FNDC5) in response to physical exercise. Studies reveal that irisin/FNDC5 has neuroprotective functions against Alzheimer's disease, the most common form of dementia in the elderly, by improving cognitive function and reducing amyloid-β and tau pathologies as well as neuroinflammation in cell culture or animal models of Alzheimer's disease. Although current and ongoing studies on irisin/FNDC5 show promising results, further mechanistic studies are required to clarify its potential as a meaningful therapeutic target for alleviating Alzheimer's disease. We recently found that irisin treatment reduces amyloid-β pathology by increasing the activity/levels of amyloid-β-degrading enzyme neprilysin secreted from astrocytes. herein, we present an overview of irisin/FNDC5's protective roles and mechanisms against Alzheimer's disease.

关键词： Alzheimer's disease exercise fibronectin typeⅢdomain-containing protein 5(FNDC5) irisin

Fundamental solutions for axi-symmetric translational motionof a microstretch fluid

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Acta Mechanica Sinica 2012年第3期28卷 605-611页

作者： h.h.Sherief M.S.Faltas e.A.Ashmawy Department of Mathematics Faculty of ScienceAlexandria University

The fundamental solution for the axi-symmetric translational motion of a microstretch fluid due to a concen- trated point body force is obtained. A general formula for the drag force exerted by the fluid on an axi-symmetric rigid par- ticle translating in it is then deduced. As an application to the obtained drag formula, this paper has discussed the problem of creeping translational motion of a rigid sphere in a mi- crostretch fluid. The slip boundary condition on the surface of the spherical particle is applied. The drag force and the other physical quantities are obtained and represented graph- ically for various values of the micropolarity and slip param- eters.

关键词： Drag force Fundamental solution Mi-crostretch fluid Slip condition

exact solution for the unsteady flow of a semi-infinite micropolar fluid

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Acta Mechanica Sinica 2011年第3期27卷 354-359页

作者： h.h. Sherief M.S. Faltas e.A. Ashmawy Department of Mathematics Faculty of ScienceAlexandria University

The unsteady motion of an incompressible micropolar fluid filling a half-space bounded by a horizontal infinite plate that started to move suddenly is considered. Laplace transform techniques are used. The solution in the Laplace transform domain is obtained by using a direct approach. The inverse Laplace transforms are obtained in an exact manner using the complex inversion formula of the transform together with contour integration techniques. The solution in the case of classical viscous fluids is recovered as a special case of this work when the micropolarity coecient is assumed to be zero. Numerical computations are carried out and represented graphically.

关键词： Unsteady motion . Laplace transform . Microp-olar fluid

Identifying suitable areas for plenter forest management

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Forest ecosystems 2025年第01期 83-92页

作者： Mathias Leiter Christoph Pucher Michael Kessler Ferdinand h?nigsberger Manfred J.Lexer harald Vacik hubert hasenauer Institute of Silviculture University of Natural Resources and Life Sciences (BOKU) Institute of Forest engineering University of Natural Resources and Life Sciences (BOKU)

Plenter forests, also known as uneven-aged or continuous cover forests enhance forest resilience and resistance against disturbances compared to even-aged forests. They are considered as an adaptation option to mitigate climate change effects. In this study, we present a conceptual approach to determine the potentially suitable area for plenter forest management within central european mixed species forests and apply our approach to the case study area in Styria, the south-eastern Province of Austria. The concept is based on ecological and technicaleconomic constraints and considers expected future climate conditions and its impact on plenter forest management. For each 1 ha forest pixel, we assess the ecological conditions for plenter forest management according to the autecological growth conditions of silver fir, and at least one additional shade tolerant tree species. The technical-economic constraints are defined by slope(≤30%) and distance to the next forest road(≤100 m) to ensure cost-efficient harvesting. The results show that under current climate conditions 28.1% or 305,349 ha of the forests in Styria are potentially suitable for plenter forest management. For the years 2071–2100 and under the climate change scenario RCP 4.5, the potential area decreases to 286,098 ha(26.3% of the total forest area)and for the scenario RCP 8.5 to 208,421 ha(19.1% of the total forest area). The main reason for these changes is the unfavourable growing conditions for silver fir in the lowlands, while in the higher elevations silver fir is likely to expand. Our results may serve forest managers to identify areas suitable for plenter forests and assist in the transformation of even-aged pure forests to uneven-aged forests to increase resistance, resilience, and biodiversity under climate change.

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Statistical research on the motion properties of the magnetotail current sheet:Cluster observations

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Science China(Technological Sciences) 2010年第6期53卷 1732-1738页

作者： h.ReMe e.LUCeK Centre D'etude Spatiale des Rayonnements University Paul SabatierUniversity of ToulouseToulouseFrance UMR 5187 CNRSToulouseFrance Space and Atmospheric Physics Group Blackett LaboratoryImperialCollegeLondonUK

The origin of the flapping motion of the earth’s magnetotail current sheet is one of the most important problems in the magnetotail *** Cluster data,we make a statistical research on the motion properties of the magnetotail current sheet of 2001 and *** calculate the velocities of the magnetotail current sheet using new methods and obtain the distribution of the magnetotail current sheet velocities in the X-Y plane in GSe coordinate *** results show that although most of the current sheets were propagating toward the tail flanks and those of the exceptions lay in dusk side,which is consistent with previous studies,the proportions of the current sheet which were propagating toward midnight (where |YGSe|=0) were higher than those in previous *** of the current sheet in the middle area (|YGSe|e) of the magnetotail are *** high value of the Z component of the velocity further confirms that the middle area of the magnetotail might be a source region for the motion of the current sheets which were propagating towards the tail *** to our case studies,the way the current sheets propagated toward midnight area differs significantly from that toward dusk and dawn side,from which we infer that there might be two different kinds of current sheet motions originated from different *** statistical results of this paper may give some clues for further studies on the origin of the flapping motion of the magnetotail current sheet.

关键词： magnetotail current sheet flapping motion source

国际矿物学协会新矿物及矿物命名委员会关于矿物命名的程序和原则(1997年)

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矿物学报 2000年第4期20卷 415-424页

作者： ernest h.nickel Joel D.Grice 联邦科学与工业研究组织勘查及采矿部澳大利亚文布利加拿大自然博物馆加拿大渥太华

Use of virtual reality in underground roof fall hazard assessment and risk mitigation

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International Journal of Mining Science and Technology 2019年第4期29卷 603-607页

作者： e.Isleyen h.S.Duzgun Department of Mining engineering Colorado School of Mines

Virtual reality(VR)simulations are some of the alternative practice environments for safety *** gain experience under the most realistic conditions without being exposed to any real *** reality also serves as a tool to expedite the decision-making process where quick decisions and actions are necessities for a safe *** example of such a situation in underground mines is the failure risks in a tunnel face after *** support systems must be installed based on the stand-up time to ensure the safe access of personnel and equipment to the working ***,a competent person inspects the area to identify risks and determines the required support ***,training of a competent person requires large amount of time and *** study presents virtual reality simulations developed for improving the assessment of the roof fall hazards and taking necessary measures for mitigating the risk related to roof *** virtual reality simulation involves decision-making tasks for a particular scenario in which participants can experience creating a safe working environment in a timely ***,they are asked to identify the potential hazard in a tunnel after blasting,namely,rock fall,wedge failure or groundwater *** the hazard identification is successful,participants are requested to install rock bolts as a safety measure by selecting the bolt pattern(*** length and spacing).Finally,participants evaluate the roof fall hazard by viewing displacements around the opening,before and after the support *** study illustrates the benefits of VR in safety training as well as enhancing the decision-making process to enhance safety.

关键词： Virtual reality hazard assessment Tunneling