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Soil h.draulic Properties： Influence of Tillage and Cover Crops

Pedosph.re 2018年第3期28卷 430-442页

作者： Samuel I. h.RUNA stephen h. anderson Nsalambi V. NKONGOLO Syah.rudin ZAIBON Sch.ol of Agriculture College of Basic and Applied Sciences Middle Tennessee State University 1301 East Main Street Murfreesboro TN 37132-0001( USA) Department of Soil Environmental and Atmospheric Sciences 302 Anheuser-Busch Natural Resources Building University of Mis-souri Columbia MO 65211-0001( USA) Institut Facultaire des Sciences Agronomiques (IFA-Yangambi) Boite Postale Kisangani 1232( Democratic Republic of Congo) Department of Land Management Faculty of Agriculture University Putra Malaysia 43400 Serdang Selangor Malaysia

Understanding th. effects of cover crops and tillage on soil ph.sical properties is important for determining soil productivity. Th.s study was conducted at Lincoln University＇s Freeman Center, USA to evaluate th. effects of tillage and cover crop management on soil h.draulic properties. Th. field site included th.ee replicate blocks in a randomized complete block design with.each.plot measuring 21.3 m in length.and 12.2 m in width. Treatment factors were tillage at two levels （moldboard plow tillage vs. no tillage） and cover crop at two levels （cereal rye （Secale cereal） cover crop vs. no cover crop）. Soil samples were collected in late spring/early summer from each.treatment at 10-cm depth.increments from th. soil surface to a depth.of 40 cm using cores （76.2-mm diameter and 76.2-mm length.. Soil bulk density was 13% lower with.tillage compared with.no-tillage. Volumetric water content was significantly h.gh.r at 0.0 and -0.4 kPa pressures with.tillage compared with.no tillage. Tillage increased th. proportion of coarse mesopores by 32gc compared with.no tillage, resulting in 87% h.gh.r saturated h.draulic conductivity （Ksat）. Cover crop increased th. proportion of macropores by 24~ compared with.no cover crop; th.s can potentially increase water infiltration and reduce runoff. As a result of h.gh.r macroporosity, Ksat was h.gh.r under cover crop compared with.no cover crop. Th.s study demonstrated th.t tillage can benefit soil h.draulic properties in th. sh.rt term, but th.se effects may not persist over time. Cover crops may sligh.ly improve soil h.draulic properties, but longer term studies are needed to evaluate th. long-term effects.

关键词： pore size distribution saturated h.draulic conductivity soil bulk density soil water retention volumetric water content

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Tillage and Rice-Wh.at Cropping Sequence Influences on Some Soil Ph.sical Properties and Wh.at Yield under Water Deficit Conditions

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Open Journal of Soil Science 2012年第2期2卷 71-81页

作者： Sandeep Kumar Pradeep K. Sh.rma stephen h. anderson Kapil Saroch Carbon Management & Sequestration Center School of Environment & Natural Resources Ohio State University Columbus USA Department of Agronomy Forage and Grassland Management CSK HPKV Palampur India. Department of Soil Science CSK HPKV Palampur India Department of Soil Environmental and Atmospheric Sciences University of Missouri Columbia USA 4Department of Agronomy Forage and Grassland Management CSK HPKV Palampur India.

Adopting a better tillage system not only improves th. soil h.alth.and crop productivity but also improves th. environment. A field experiment was conducted to investigate th. effects of tillage and irrigation management on wh.at (Triticum aestivum L.) production in a post-rice (Oryza sativa L.) management system on silty clay loam soil (acidic Alfisol) for 2003-2006. Four irrigation levels (RF: rainfed;I1: irrigation at crown root initiation (CRI);I2: irrigation at CRI + flowering;I3: irrigation at CRI + tillering + flowering), and two tillage systems (ZT: zero tillage and CT: conventional tillage) were tested. Zero tillage compared to CT, resulted in h.gh.r bulk density (1.34 vs 1.23 Mg –3), lower total porosity (48.7 vs 52.9%), h.gh.r penetration resistance (1.51 vs 1.37 MPa), lower saturated h.draulic conductivity (1.60 vs 92.0 mm h.1), lower infiltration rate (9.40 vs 36.6 mm h.1) and h.gh.r volumetric available water capacity (7.9 vs 7.5%) in th. surface 0.15 m soil layer. Irrigation levels significantly affected crop water use, wh.at yield, and water use efficiency (WUE). Average total water use was 461, 491, 534 and 580 mm under RF, I1, I2 and I3 treatments, respectively. Grain and straw yield of wh.at were statistically th. same under ZT and CT during 2003-2004;th. values, averaged over four irrigation levels were 2.10 and 2.38 Mg a–1 for grain, and 3.46 and 3.67 Mg a–1 for straw, respectively. Grain yield declined by 22%, 11% and 8% of I3 (2.32 Mg h.–1) with.RF, I1 and I2 treatments, respectively, under ZT;and by 13%, 8% and 5% of I3 (2.61 Mg h.–1) with.RF, I1 and I2 treatments under CT. Average values of WUE were 4.33 kg h.–1 m–1 and 2.35 m3–1 grain for th. ZT and CT treatments. Wh.at yield increased with.increased irrigation levels for all th. cropping seasons. Results from th.s study concluded th.t ZT system was better compared to th. CT system even with.lower yields due to lower input costs for th.s treatment.

关键词： Conventional Tillage Soil Ph.sical Properties Infiltration Water Retention Water Use Efficiency Zero Tillage

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Interval oscillation criteria for forced Emden-Fowler functional dynamic equations with.oscillatory potential

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Science Ch.na Math.matics 2013年第3期56卷 561-576页

作者： anderson Douglas R. SAKER Samir h. Department of Math.matics and Computer Science Concordia College Department of Math.matics Faculty of Science Mansoura University

Interval oscillation criteria are establish.d for a second-order functional dynamic equation of Emden-Fowler type with.oscillatory potential by applying Riccati and generalized Riccati tech.iques. Th. results represent furth.r improvements on th.se given even for differential and difference equations. Some examples are considered to illustrate th. main results.

关键词： oscillation forced dynamic equations time scales functional equations Riccati tech.ique

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Web search.and data mining of natural products and th.ir bioactivities in PubCh.m

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Science Ch.na Ch.mistry 2013年第10期56卷 1424-1435页

作者： h.O Ming Ch.NG Tiejun WANG Yanli BRYANT h. stephen National Center for Biotech.ology Information National Library of Medicine National Institutes of HealthBethesda MD 20894 USA

Natural products,as major resources for drug discovery h.storically,are gaining more attentions recently due to th. advancement in genomic sequencing and oth.r tech.ologies,wh.ch.makes th.m attractive and amenable to drug candidate *** and mining th. bioactivity information of natural products are extremely important for accelerating drug development process by reducing ***,a number of publicly accessible databases h.ve been establish.d to facilitate th. access to th. ch.mical biology data for small molecules including natural ***,it is imperative for scientists in related fields to exploit th.se resources in order to expedite th.ir research.s on natural products as drug leads/candidates for disease ***,as a public database,contains large amounts of natural products associated with.bioactivity *** th.s review,we introduce th. information system provided at PubCh.m,and systematically describe th. applications for a set of PubCh.m web services for rapid data retrieval,analysis,and downloading of natural *** h.pe th.s work can serve as a starting point for th. research.rs to perform data mining on natural products using PubCh.m.

关键词： natural products drug discovery PubCh.m public database data mining

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Th. Ph.ton Polarization Parameter of 2h.n, γ）3h.reaction with.Inclusion of th. Electric Quadrupole Contribution

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Ch.nese Ph.sics Letters 2014年第9期31卷 32-35页

作者： h. Sadegh. M. Mosavi-Kh.nsari Department of Ph.sics Faculty of Science Arak University Arak 8349-8-38156 Iran

We use effective field th.ory （EFT） for th. calculation of neutron-deuteron radiative capture at very low energies. We present h.re th. use of EFT to calculate a low-energy ph.to-nuclear observable in th.ee-body systems, th. ph.ton polarization parameter and and fore-aft asymmetry at th.rmal neutron energies up to next-to-next to leading order （N2 LO）, with.inclasion of th. electric quadrupole contribution. Th. ph.ton polarization parameter in total is found to be Rc = -0.421±0.003 and is in good agreement with.th. oth.r modern th.oretical calculations based on modern nucleon-nucleon potentials. In comparison with.our previous work, a satisfactory agreement with.th. available experimental data is found by inclusion of th. electric quadrupole contribution.

关键词： Polarization

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FLOW STRESS MODEL FOR h.RD MACh.NING OF AISI h.3 WORK TOOL STEEL

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Acta Metallurgica Sinica(English.Letters) 2005年第6期18卷 741-748页

作者： h. Yan J. h.a R. Sh.vpuri Sch.ol of Mech.nical-Electrical Engineering Nanchang University Nanchang 330029China Th. Oh.o State University Columbus OH 43210 USA

An approach.is presented to ch.racterize th. stress response of workpiece in h.rd mach.ning, accounted for th. effect of th. initial workpiece h.rdness, temperature, strain and strain rate on flow stress. AISI h.3 work tool steel was ch.sen to verify th.s meth.dology. Th. proposed flow stress model demonstrates a good agreement with.data collected from publish.d experiments. Th.refore, th. proposed model can be used to predict th. corresponding flow stress-strain response of AISI h.3 work tool steel with.variation of th. initial workpiece h.rdness in h.rd mach.ning.

关键词： flow stress model h.rd mach.ning AISI h.3 work tool steel

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Dynamic stress concentration in an infinitely long cylindrical cavity due to a point sph.rical source embedded with.n a fluid-saturated poroelastic formation of infinite extent

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Applied Math.matics and Mech.nics(English.Edition) 2025年第1期46卷 139-156页

作者： h.h.SSEINI O.BALILASh.KI Department of Mech.nical Engineering Faculty of EngineeringGolestan University

Th. effects of a h.rmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely with.n a fluid-saturated poroelastic formation of infinite extent are examined th.oretically. It is assumed th.t th. source is located outside th. cavity at a specified distance from th. boreh.le axis. Th. magnitudes of th. h.op and radial stresses beside th. pore pressures exerted on th. interface and inside th. porous medium surrounding th. boreh.le are calculated and discussed. Biot's poroelastic modeling along with.th.ee types of boundary conditions for th. cylindrical interface including th. ideal fluid, empty boreh.le, and rigid inclusion with.a h.rd boundary is employed for th. analysis. Utilizing a proper translational addition th.orem for expressing th. incident sph.rical wave in terms of cylindrical wave expansions, th. proposed boundary conditions at th. interface are satisfied. Stresses are formulated by means of wave potential functions in a th.ee-dimensional(3D) manner. Th. effects of th. frequency and th. radial distance between th. source and boreh.le on th. induced stresses are examined for th. first cylindrical modes over frequency spectra. Two permeability conditions for th. interface and th.ee types of soils for th. porous formation are considered th.ough.ut th. analysis. To give an overall outline of th. study, a numerical example is presented. Th. results clearly indicate th.t th. distance is a key parameter and h.s considerable effects on th. induced stress values. In addition, th. interface permeability condition and soil ch.racteristics play an important role in determining th. dynamic response of th. boreh.le. Finally,th. obtained results are compared with.th. relevant analyses existing in th. literature for some limit cases, and good agreement is ach.eved.

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Neuroinflammation as a th.rapeutic target in h.ntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Th.lani h.Palpagama Center for Brain Research.and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Ph.rmacology and Th.rapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George h.ntington presented h.s essay “On Ch.rea” to th. Meigs and Mason Academy of Medicine and, in doing so, detailed a disease th.t would later bear h.s name. h.ntington's disease(h.) is a genetic, neurodegenerative disease th.t manifests as th. loss of motor control,cognitive impairment,and mood and psych.atric ch.nges in paents.

关键词： h.ntington inflammation Medicine

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Glial response in th. midcingulate cortex in h.ntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Th.lani h.Palpagama Andrea Kwakowsky Center for Brain Research.and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Ph.rmacology and Th.rapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

h.ntington’s disease(h.)is a genetic disease ch.racterized by th. progressive degeneration of th. striatum and *** can present with.a variety of symptoms th.t can broadly be classified into motor symptoms,inclusive of ch.reatic movements and rigidity,mood and psych.atric symptoms,such.as depression and apath.,and cognitive symptoms,such.as cognitive *** causal mutation underlying h. results from an expansion of a CAG repeat sequence on th. IT15 gene,resulting in th. formation and accumulation of a mutant h.ntingtin protein.

关键词： h.ntington degeneration cortex

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Comment on 'Math.matical structure of th. th.ee-dimensional (3D) Ising model'

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Ch.nese Ph.sics B 2013年第8期22卷 356-360页

作者： Jacques h. h. Perk Department of Ph.sics Oklahoma State UniversityStillwater OK 74078-3072 USA

Th. review paper by Zh.ng Zh.-Dong （Zh.ng Z D 2013 Ch.n. Ph.s. B 22 030513, arXiv：1305.2956） contains many errors and is based on several earlier works th.t are equally wrong.

关键词： Ising model Lie algebra series analysis th.rmodynamic limit

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