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河海科技进展 1992年第4期12卷 108-116页

作者： f.k.ewert 章杨松

1—2.3 (略)2.4 与水库和大坝有关的地下水2.4.1 (略)2.4.2 水库的不透水性如果邻近存在一沟谷,且水库和邻近沟谷间的岩体非常透水,则水库的不透水性就会受到威胁。此时地下水位通常很低,不超过库水位。如在图4(略)中形成渗过山体的渗... 详细信息

1—2.3 (略)2.4 与水库和大坝有关的地下水2.4.1 (略)2.4.2 水库的不透水性如果邻近存在一沟谷,且水库和邻近沟谷间的岩体非常透水,则水库的不透水性就会受到威胁。此时地下水位通常很低,不超过库水位。如在图4(略)中形成渗过山体的渗流流线,水流渗向邻近的沟谷。在极端不利情况下这会妨碍水库的蓄水。

关键词：地下水渗流控制工程地质渗流

Commentary on“Incidence of urinary incontinence following endoscopic laser enucleation of the prostate by en-bloc and non-en-bloc techniques:a multicenter,real-world experience of 5068 patients”

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Asian Journal of Andrology 2024年第3期26卷 333-334页

作者： James f Jiang Narmina k Onder Akhil k Das Department of Urology University of California Irvine Orange CA 92868 USA.

Laser enucleation of the prostate is a proven and effectivesize-independent method for the surgical management of symptomaticbenign prostatic hyperplasia(BPH)and is considered as the“goldstandard”by many *** major hurdles that stand in theway of this becoming a universally used procedure for BPH are thesteep learning curve associated with mastering the procedure andpossibility of perioperative transient *** advances inteaching methodologies have helped tackle the difficulty in learning itand increased the number of urologists utilizing the *** forthe second hurdle,transient incontinence rates postlaser enucleationof the prostate have improved with the advent of newer techniques *** et al.1 assesses the incidence of stress,urge,andmixed urinary incontinence following laser enucleation of the prostateby comparing en-bloc and non-en-bloc techniques in a multicenterseries of 5068 men with BPH.

关键词： urinary incontinence transient

New evidence for the epigenetic regulation of skeletal stem cells

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Science Bulletin 2024年第13期69卷 2004-2006页

作者： Liming Zhao Jun Xiao Charles k.f.Chan Institute for Stem Cell Biology and Regenerative Medicine Stanford University School of MedicineStanford CA 94305USA Department of Surgery Division of Plastic and Reconstructive SurgeryStanford University School of MedicineStanford CA 94305USA Department of Orthopaedic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Skeletal stem cells(SSCs)are crucial for skeletal development and regeneration,yet the epigenetic regulation of these cells remains poorly *** studies have delineated the epigenetic landscape across the developmental trajectory of SSCs,highlighting the involvement of Ptip in regulating SSC *** skeletal system undergoes dynamic remodeling throughout *** stem cells(SSCs),residing within the skeleton and lineage-restricted,serve as a cellular reserve to foster development and maintain skeletal *** categorized within the broader mesenchymal stromal/stem cells(MSCs).

关键词： skeletal involvement maintain

Tuning the optoelectronic properties for small organic compounds as organic solar cell applications

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Optoelectronics Letters 2024年第7期20卷 412-417页

作者： Hussein k.Mejbel Lafy f.Al-Badry Department of Physics College of Education for Pure ScienceUniversity of Thi-QarNassiriya 64001Iraq Department of Physics College of ScienceUniversity of Thi-QarNassiriya 64001Iraq1

Recently,organic solar cells have attracted the attention of many researchers owing to flexibility,low cost,light weight and large-area applications,and significant improvement in the power conversion efficiency(PCE).In this work,we designed chains from organic compounds as donors and replaced the core unit in each series with a variety of acceptors in order to enhance their optical and electronic characterization and performance for power conversion efficiencies in organic solar *** utilized density functional theory(DfT)and time-dependent density functional theory(TD-DfT)to investigate the geometry optimization by using the Gaussian 09 *** electronic and optical properties were determined,which involve the lowest unoccupied molecular orbital(LUMO)and the highest occupied molecular orbital(HOMO)levels,the band gap energy,maximum absorption wavelength(λmax),open circuit voltage(Voc),and light harvesting efficiency(LHE).Our evaluation denotes that the small compounds suggested are predicted to exhibit the best performance compared to the first series(SC1),like a lower band gap energy,a lower HOMO energy level,a greater absorption range,and a larger PCE.

关键词： orbital occupied compounds

finite element analysis and experimental validation of polymer-metal contacts in block-on-ring configuration

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friction 2024年第3期12卷 554-568页

作者： k.Y.Eayal AWWAD khosro fALLAHNEZHAD B.f.YOUSIf Ahmad MOSTAfA Omar ALAJARMEH A.SHALWAN Xuesen ZENG Mechanical Engineering Department Faculty of EngineeringTafila Technical UniversityTafila 66110Jordan Medical Device Research Institute College of Science and EngineeringFlinders UniversitySouth Australia 5042Australia Centre for future Materials University of Southern QueenslandToowoomba 4350Australia Department of Manufacturing Engineering Technology Public Authority for Applied Education and TrainingKuwait 13092Kuwait

The wear profile analysis,obtained by different tribometers,is essential to characterise the wear ***,most of the available methods did not take the stress distribution over the wear profile in consideration,which causes inaccurate *** this study,the wear profile of polymer–metal contact,obtained by block-on-ring configuration under dry sliding conditions,was analysed using finite element modelling(fEM)and experimental ***’s wear equation was integrated into a developed fORTRAN-UMESHMOTION code linked with Abaqus software.A varying wear coefficient(k)values covering both running-in and steady state regions,and a range of applied loads involving both mild and severe wear regions were measured and implemented in the *** fEM was in good agreement with the *** model reproduced the stress distribution profiles under variable testing conditions,while their values were affected by the sliding direction and maximum wear depth(hmax).The largest area of the wear profile,exposed to the average contact stresses,is defined as the normal *** the critical zones were characterized by high stress concentrations reaching up to 10 times of that at the normal *** wear profile was mapped to identify the critical zone where the stress concentration is the key point in this *** surface features were examined in different regions using scanning electron microscope(SEM).Ultimately,SEM analysis showed severer damage features in the critical zone than that in the normal zone as proven by ***,the literature data presented and considered the wear features the same at any point of the wear *** this study,the normal zone was determined at a stress value of about 0.5 MPa,whereas the critical zone was at about 5.5 *** wear behaviour of these two zones showed totally different features from one another.

关键词： polymer-to-metal contact block-on-ring wear profile wear model

Analysis of the Impact of the Blazhko Effect Both on the Van Hoof Effect and Radial Velocity Amplitude in the Star RR Lyr

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Research in Astronomy and Astrophysics 2024年第6期24卷 253-272页

作者： Y.El jariri f.L.Sefyani A.Benhida Z.Benkhaldoun k.kolenberg k.Chafouai A.Habib M.Sabil Observatoire de l'Oukaimeden LPHEAFSSMUniversitéCadi AyyadMarrakech2390Morocco Observatoire de l'Oukaimeden LPHEAFSTGUniversitéCadi AyyadMarrakech549Morocco Département de physique Universitéd'Anvers Avenue Groenenborger 171Anvers2020Belgium LICPM ENSA-BMUniversitéSultan Moulay SlimaneBeni-Mellal23020Morocco

The Van Hoof effect is a phase shift existing between the radial velocity curves of hydrogen and metallic lines within the atmosphere of pulsating *** this article,we present a study of this phenomenon through the spectra of the brightest pulsating star RR Lyr of RR Lyrae stars recorded for 22 *** based ourselves,on the one hand,on 1268 spectra(41 nights of observation)recorded between the years 1994 and 1997 at the Observatory of Haute Provence(OHP,france)previously observed by Chadid and Gillet,and on the other hand on 1569 spectra(46nights of observation)recorded at our Oukaimeden Observatory(Morocco)between 2015 and *** this study,we have detected information on atmospheric dynamics that had not previously been ***,the Van Hoof effect which results in a clear correlation between the radial velocities of hydrogen and those of the metallic lines has been observed and analyzed at different Blazhko phases.A correlation between the radial velocities of different metallic lines located in the lower atmosphere has been observed as *** the first time,we were able to show that the amplitude of the radial velocity curves deduced from the lines of hydrogen and that of feⅡ(λ4923.921?)increases toward the minimum of the Blazhko cycle and decreases toward the maximum of the same Blazhko ***,we found that the Van Hoof effect is also modulated by the Blazhko ***,toward the minimum of the Blazhko cycle the Van Hoof effect is more visible and at the maximum of the Blazhko cycle,this effect is *** also observed the temporal evolution of the amplitudes of the radial velocities of the lower and upper *** observed over a long time,we can interpret it as a function of the Blazhko phases.

关键词： stars:atmospheres stars:variables:RR Lyrae shock waves techniques:spectroscopic techniques:radial velocities stars:individual(RR Lyr)

The magnetosheath at high spectral resolution

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Earth and Planetary Physics 2024年第1期8卷 234-246页

作者： k.D.küntz D.koutroumpa W.R.Dunn A.foster f.S.Porter D.G.Sibeck B.Walsh The Henry A.Rowland Department of Physics and Astronomy Johns Hopkins University3701 San Martin DriveBaltimoreMD21218USA NASA Goddard Space flight Center 8800 Greenbelt RoadGreenbeltMD 20771USA LATMOS-OVSQ CNRSUVSQ Paris-SaclaySorbonne Université11 Boulevard d’Alembert78280GuyancourtFrance Department of Physics and Astronomy University College LondonLondonUK The Centre for Planetary Science at UCL/Birkbeck Gower StreetLondon WC1E 6BTUK Center for Astrophysics Harvard University&Smithsonian Institution60 Garden StreetCambridgeMA 02138USA Center for Space Physics Boston University110 Cummington MallBostonMAUSA

While we eagerly anticipate SMILE’s(Solar wind Magnetosphere Ionosphere Link Explorer)unprecedented X-ray observations of the Earth’s magnetosheath and the initiation of a new era of magnetospheric research,it seems appropriate to look ahead to the abilities of the next generation of astrophysics *** these,the Line Emission Mapper(LEM),a large aperture micro-calorimeter based mission,is currently planned to be able to observe the magnetosheath at high spectral resolution(~2 eV).With a field of view of~30′,LEM will allow higher spatial resolution and higher cadence measurement of the motion of a very small portion of the magnetopause over relatively short periods of time(multiple hours),complementing SMILE’s global ***’s strength is its spectral *** will be able to measure the abundance of a broad range of elements and ionization states,many of which are inaccessible to current in situ instruments,and will be able to separate the emission from the magnetosheath from the emission from the cosmic X-ray background using the difference in their relative velocities.

关键词： magnetosheath charge exchange solar wind abundances

Numerical Analysis of the Magnetic Dipole Effect on a Radiative ferromagnetic Liquid flowing over a Porous Stretched Sheet

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fluid Dynamics & Materials Processing 2024年第2期20卷 293-310页

作者： G.Dharmaiah f.Mebarek-Oudina k.S.Balamurugan N.Vedavathi Department of Mathematics Narasaraopeta Engineering CollegeNarasaraopetIndia Department of Physics Faculty of SciencesUniversity of 20 Août 1955-SkikdaSkikdaAlgeria Department of Mathematics RVR&JC College of EngineeringGunturIndia Department of Mathematics Koneru Lakshmaiah Education FoundationVaddeswaramIndia

The effects of a magnetic dipole on a nonlinear thermally radiative ferromagnetic liquidﬂowing over a stretched surface in the presence of Brownian motion and thermophoresis are *** means of a similarity transformation,ordinary differential equations are derived and solved afterwards using a numerical(the BVP4C)*** impact of various parameters,namely the velocity,temperature,concentration,is presented *** is shown that the nanoparticles properties,in conjunction with the magnetic dipole effect,can increase the thermal conductivity of the engineered nanoﬂuid and,consequently,the heat *** with earlier studies indicates high accuracy and effectiveness of the numerical *** increase in the Brow-nian motion parameter and thermophoresis parameter enhances the concentration and the related boundary *** skin-friction rises when the viscosity parameter is increased.A larger value of the ferromagnetic para-meter results in a higher skin-friction and,vice versa,in a smaller Nusselt number.

关键词： Brownian motion thermo-phoresis radiation magnetic dipole BVP4C non-linear

Applying Earth Observation Technologies to Economic Consequence Modeling:A Case Study of COVID‑19 in Los Angeles County,California

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International Journal of Disaster Risk Science 2024年第1期15卷 18-31页

作者： fynnwin Prager Marina T.Mendoza Charles k.Huyck Adam Rose Paul Amyx Gregory Yetman kristy f.Tiampo California State University Dominguez HillsCarsonCA 90747USA ImageCat Inc.Long BeachCA 90802USA University of Southern California Los AngelesCA 90015USA CIESIN–Center for International Earth Science Information Network Columbia UniversityPalisadesNY 10964USA Cooperative Institute for Research in Environmental Sciences(CIRES) University of Colorado BoulderBoulderCO 80309USA

Earth observation(EO) technologies,such as very high-resolution optical satellite data available from Maxar,can enhance economic consequence modeling of disasters by capturing the fine-grained and real-time behavioral responses of businesses and the *** investigated this unique approach to economic consequence modeling to determine whether crowd-sourced interpretations of EO data can be used to illuminate key economic behavioral responses that could be used for computable general equilibrium modeling of supply chain repercussions and resilience *** applied our methodology to the COVID-19 pandemic experience in Los Angeles County,California as a case *** also proposed a dynamic adjustment approach to account for the changing character of EO through longer-term disasters in the economic modeling *** found that despite limitations,EO data can increase sectoral and temporal resolution,which leads to significant differences from other data sources in terms of direct and total impact *** findings from this analytical approach have important implications for economic consequence modeling of disasters,as well as providing useful information to policymakers and emergency managers,whose goal is to reduce disaster costs and to improve economic resilience.

关键词： Computable general equilibrium models COVID-19 Disaster economic impacts Earth observation Economic consequence analysis Los Angeles County