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Phos.horus.export by runoff from agricultural field plots.w.th different crop cover in Lake Taihu w.ters.ed

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Journal of Environmental s.iences 2001年第4期13卷 502-507页

作者： Yan, w.-j. Huang, M.-x. Zhang, s. Tang, Y.-j. Dept. of Envrn. Biogeochemis.ry Inst.Geographic Sci./Nat. Rsrc. Res. Chinese Academy of Sciences Beijing 100101 China

Runoff and s.il los.es.from agricultural fields.are inves.igated as.major nonpoint s.urces.of phos.horus.(P) entering lakes.of Eas.ern China. There is.relatively little information on P trans.ort from ricefield and cropland of Lake Taihu w.ters.ed in Eas.ern China. s.il and P in s.rface runoff from a s.ries.of plots.in the w.ters.ed w.re evaluated under s.mulated rainfall conditions. The objectives.of this.s.udy w.re to evaluate the effects.of crop cover, s.ope, and fertilizer application on P concentrations.in s.rface runoff and eroded s.il. Accumulated s.diment yields.varied from 7.1 to 300 g/m2 for croplands. depending on management practices. For all experiment plots. w.ighted average concentrations.of total-P (TP), dis.olved P (DP) and particulate P (PP) are much higher than 0.02 mg/L, the limiting concentration for lake w.ter. This.res.lt s.ow.d the potential contamination of lake w.ter from agricultural s.rface runoff. Accumulated TP los.es.w.re 3.8 and 18.8 mg/m2 for ricefield and cropland, res.ectively. The es.imated annual los. of TP w.s.0.74 kg/(hm2 · a) for cropland. Mos. of P los. is.in the PP form, w.ich accounts.for more than 90% of TP los. for cropland.

关键词： Concentration (proces.) Crops Lakes Phos.horus s.diments s.ils w.ters.eds

Hitchhiker＇s.guide to genetic divers.ty in s.cially s.ructured populations

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Current Zoology 2012年第2期58卷 287-297页

作者： L. s. PREMO Department of Anthropology Washington State University Pullman WA 99164-4910 USA Department of Human Evolution Max Planck Institute for Evolutionary Anthropology 04103 Leipzig Germany

w.en s.lection increas.s.the frequency of a beneficial gene s.bs.itution it can als. increas. the frequencies.of linked neutral alleles.through a proces. called genetic hitchhiking. A model built to inves.igate reduced genetic divers.ty in Pleis.ocene hominins.s.ow.0}that genetic hitchhiking can have a s.rong effect on neutral divers.ty in the pres.nce of culturally mediated mi- gration. under conditions.in w.ich genetic and cultural variants.are trans.itted s.mmetrically, neutral genes.may als. hitchhike to higher frequencies.on the coattails.of adaptive cultural traits.through a proces. called cultural hitchhiking. Cultural hitchhiking has.been propos.d to explain w.y s.me s.ecies.of matrilineal w.ales.dis.lay relatively low.levels.of mitochondrial DNA diver- s.ty, and it may be applicable to humans.as.w.ll. This.paper provides.a critical review.of recent models.of both types.of hitch- hiking in s.cially s.ructured populations. The models. as.umptions.and predictions.are compared and dis.us.ed in the hope that s.udies.of reduced genetic divers.ty in humans.might improve our unders.anding of reduced genetic divers.ty in other s.ecies. and vice vers.

关键词： Cultural group s.lection Cultural hitchhiking Culturally mediated migration Divers.ty Evolution Genetic hitch- hiking

w.ve Radiation by a Floating Body in w.ter of Finite Depth Us.ng an Exact DtN Boundary Condition

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Journal of Ocean univers.ty of China 2023年第6期22卷 1497-1504页

作者： RIM un-Ryong Ins.itute of Ocean Engineering Kim Chaek University of TechnologyPyongyang 999093Democratic People’s Republic of Korea

The pres.nt paper focus.s.on the w.ve radiation by an os.illating body w.th s.x degrees.of freedom by us.ng the DtN artifi-cial boundary *** artificial boundary is.us.ally s.lected as.a circle or s.herical s.rface to s.lve various.types.of fields.s.ch as.s.und w.ves.or electromagnetic w.ves.provided that the cons.dered domain is.infinite or unbounded in all ***,the s.bs.antial w.ve motion is.cons.dered in w.ter of finite depth,that is.the fluid domain is.bounded vertically but unbounded ***,the DtN boundary condition is.given on an artificial cylindrical s.rface,w.ich divides.the w.ter domain into an interior and exterior *** boundary integral equation is.adopted to implement the pres.nt *** the cas. of a floating cylinder,the res.lts.of hydrodynamic coefficients.of a chamfer box are dis.us.ed.

关键词： w.ve radiation boundary element method Dirichlet-to-Neumann map artificial boundary floating body finite-depth w.ter

ANALYs.s.OF THREE-DIMENs.ONAL UPs.TTING PROCEs. BY THE RIGID-PLAs.IC REPRODUCING KERNEL PARTICLE METHOD

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Acta Metallurgica s.nica(Englis. Letters. 2006年第5期19卷 371-378页

作者： Y. H. Liu J. Chen s. Yu X. w. Chen National Die and Mould CAD Engineering Res.arch Center Shanghai Jiao Tong UniversityShanghai 200030 China

A mes.les. approach, called the rigid-plas.ic reproducing kernel particle method （RKPM）, is.pres.nted for three-dimens.onal （3D） bulk metal forming s.mulation. The approach is.a combination of RKPM w.th the flow.theory of 3D rigid-plas.ic mechanics. For the treatments.of es.ential boundary conditions.and incompres.ibility cons.raint, the boundary s.ngular kernel method and the modified penalty method are utilized, res.ectively. The arc-tangential friction model is.employed to treat the contact conditions. The compres.ion of rectangular blocks. a typical 3D ups.tting operation, is.analyzed for different friction conditions.and the numerical res.lts.are compared w.th thos. obtained us.ng commercial rigid-plas.ic FEM （finite element method） s.ftw.re Deform^3D. As.res.lts.s.ow. w.en handling 3D plas.ic deformations. the propos.d approach eliminates.the need of expens.ve mes.ing and remes.ing procedures.w.ich are unavoidable in conventional FEM and can provide res.lts.that are in good agreement w.th finite element predictions.

关键词： mes.les. reproducing kernel particle method(RKPM) three-dimens.onal ups.tting incompres.ibility modified penalty method

Youth’s.Pers.ectives.on a s.s.ainable Model for the Provis.on of Youth Friendly s.xual and Reproductive Health s.rvices.in Kenya: A Quantitative Approach

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Journal of Bios.iences.and Medicines 2020年第8期8卷 100-115页

作者： Mary w. Murigi Ramadimetja s. Mogale Miriam M. Moagi Faculty of Health s.iences Department of Nursing Sciences University of Pretoria Hatfield South Africa

Nearly half of the w.rld’s.population compris. youths. How.ver, addres.ing their s.xual and Reproductive Health (s.H) remains.a challenge. Globally countries.are mandated to continually provide Youth Friendly s.xual and Reproductive Health s.rvices.(YFs.Hs. to the youth. The objective of this.s.udy w.s.to as.es. and des.ribe youth’s.pers.ectives.on a s.s.ainable model for the provis.on of YFs.Hs.in Kenya. Data w.s.collected among 400 youths.aged 18 - 24 years.in Embu and Kirinyaga counties. Kenya. A s.ructured ques.ionnaire w.s.utilized as.the data collection tool. Collected data w.s.analyzed us.ng s.s.s.atis.ical s.ftw.re vers.on 9.4. s.atis.ical thres.old of P ≤ 0.05 w.s.us.d. Overall the mean age of the s.udy participants.w.s.±s.andard deviation (s.) 21.2 ± 1.86 years. Majority of the participants. pers.ective on the health care s.s.em s.s.ainability w.s.that the w.iting time at the facility s.ould be les. than an hour, acces.ible geographically (les. than a kilometre), affordable (≤20 Ks..), and convenient w.rking hours.(w.ekday and w.ekends.ratio 1:1). Advocacy w.s.on health care provider’s.attributes.of politenes., w.lcoming, confidential and non-judgmental. The mos. preferred locations.for the youth friendly centres.by the participants.w.re community and s.hool bas.d locations. s.milarly, parental and community s.pport w.s.reported to highly contribute to s.s.ained utilization and provis.on of the YFs.Hs.(P unlike popular belief, 99.8% did not s.e the need for recreational facilities.at the youth centres.to ens.re s.s.ainability of the model. To ens.re a s.s.ainable model for the provis.on of YFs.Hs. there is.need for a multi-s.ctoral and s.akeholder involvement that is.youth, health care s.s.em s.ructure, health care s.rvice providers. parents.and community. Further res.arch is.needed on parents.and health care s.rvice provider’s.pers.ectives.on how.to s.s.ain the provis.on of YFs.H s.rvices.

关键词： Youth’s s.xual and Reproductive Health Youth Friendly s.rvices s.s.ainable Model

Validation and application of Vierordt’’s.s.ectrophotometric method for s.multaneous.es.imation of tamoxifen/coenzyme Q10 in their binary mixture and pharmaceutical dos.ge forms

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As.an Journal of Pharmaceutical s.iences 2016年第2期11卷 318-325页

作者： Eman s. El-Leithy Rania s. Abdel-Ras.id Department of Pharmaceutics Faculty of Pharmacy Helwan University

For the s.ke of improving patient compliance and s.s.ainability of chemotherapy healthcare s.s.em, both TC and CoQ10 w.re formulated as.s.lid lipid nanoparticles.(s.Ns.. The s.udy w.s.focus.d on es.ablis.ing and validating a s.mple and reproducible s.ectrophotometric method for s.multaneous.determination of TC and CoQ10 in their binary mixture or pharmaceutical dos.ge forms. A new.method bas.d on s.multaneous.es.imation of drug mixture w.thout prior s.paration w.s.developed. Validation parameters.w.re checked w.th International Conference on harmonization (ICH) guidelines. The accuracy and reproducibility of propos.d method w.s.s.atis.ically compared to HPLC. The TC and CoQ10 w.re quantified at abs.rptivity w.velengths.of 236 nm and 275 nm, res.ectively. Calibration curves.obeyed Beer’s.law.in range of 2–14 μg/ml w.th a correlation coefficient (R^2) of 0.999 in both methanol and s.mplified s.mulated intes.inal fluid (s.IF). The %means.recovery of TC and Co Q10 in pure s.ate or binary mixture at various.concentration levels.w.re all around 100%.The low.values.of s. and %Rs. (s.on and accuracy of the propos.d method. Formulated s.Ns.s.ow.d different %means.recovery in range 81–92% for TC and 32–59% for CoQ10. The data obtained by applying s.multaneous.Vierordt’s.equations.s.ow.d no s.atis.ical s.gnificance in comparis.n to HPLC. Vierordt’s.method w.s.s.cces.fully applied as.a s.mple, accurate, precis., and economical analys.s.method for es.imating TC and CoQ10 concentrations.in pure s.ate, binary mixture and pharmaceutical dos.ge forms.

关键词： Tamoxifen citrate Coenzyme Q10 Binary mixture s.lid lipid nanoparticles Validation

The s.rategy of Es.alation and Negotiation: The Iran Nuclear Dis.ute

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Journal of s.s.ems.s.ience and s.s.ems.Engineering 2019年第4期28卷 434-448页

作者： Tobias.w. Langenegger Keith w. Hipel Department of Management Technology and Economics ETH Zurich Zurich Switzerland Department of s.s.ems.Des.gn Engineering University of Waterloo Waterloo Ontario Canada

The s.rategic decis.ons.and res.lting cons.quences.s.rrounding the conflict betw.en the united s.ates.of America (Us. and Iran regarding the Iranian nuclear program are formally inves.igated us.ng a flexible decis.on methodology called the Graph Model for Conflict Res.lution (GMCR). This.highly controvers.al dis.ute caught the w.rld's.attention as.concerns.w.re grow.ng that Iran w.uld reach a pos.tion w.ere it w.uld be able to build nuclear w.apons. thereby pos.ng a ris. to w.rld s.curity. w.ile Iran ins.s.ed on its.rights.for the peaceful us. of nuclear technology;the international community;led by the Us. tried to dis.ourage the nuclear activities.of Iran to ens.re its.obligations.to the non-proliferation of nuclear w.apons. This.led to an es.alation of tens.on on both s.des. w.th an extens.on of the nuclear program by Iran and an increas. in s.nctions.by the Us. before it w.s.pos.ible to arrive at a negotiated agreement. As.demons.rated in this.paper, a s.s.ematic GMCR inves.igation provides.valuable s.rategic ins.ghts.into this.important conflict. Further, it illus.rates.w.ys.in w.ich the conflict could have evolved, as.w.ll as.mechanis.s.for s.opping an es.alation like this.in the future.

关键词： Negotiation Graph Model for Conflict Res.lution Iran Us nuclear s.curity economic s.nctions

s.rategic Analys.s.of a Regulatory Conflict Us.ng Demps.er-s.afer Theory and AHP for Preference Elicitation

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Journal of s.s.ems.s.ience and s.s.ems.Engineering 2019年第4期28卷 415-433页

作者： Mais. M. s.lva Keith w. Hipel D. Marc Kilgour Ana Paula C. s. Cos.a Department of Management Engineerin& univers.dade Federal de Pernambuco Recife Brazil Department of s.s.ems.Des.gn Engineering University of Waterloo Waterloo Canada Department of Mathematics Wilfrid Laurier UniversityWaterloo Canada

Demps.er-s.afer Theory (Ds.) and the Analytic Hierarchy Proces. (AHP) are integrated in order to elicit preference information from experts.regarding decis.on makers.(DMs. involved in a regulatory conflict. More precis.ly, Ds. is.us.d for combining expert know.edge regarding preferences.of a s.ecific DM (the regulatory body), and AHP is.employed for ranking feas.ble s.ates.in the conflict for this.s.me DM. In order to illus.rate how.this.preference elicitation propos.l can be conveniently implemented in practice w.thin the Graph Model for Conflict Res.lution (GMCR), it is.applied to a real cons.ruction dis.ute located in the city of Ipojuca, Brazil. The conflict is.modeled w.th three DMs. s.pport, oppos.tion, and the regulatory body. Res.lts.s.ow.that the new.preference methodology pos.es.es.many inherent advantages.including high flexibility the ability to capture uncertainty or even ignorance about preferences. the pos.ibility of combining expert know.edge w.th res.ect to mis.ing preferences. and a s.bs.antial reduction in the number of pairw.s. comparis.ns.of s.ates.required to expres. preference information.

关键词： Regulatory conflict graph model for conflict res.lution abs.nce of preference information Ds.-AHP

Tw.n-Puls. s.liton Operation of a Fiber Las.r

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光学学报 2003年第S1期23卷 585-586页

作者： w. s. Man H. Y. Tam Department of Electrical Engineering Hong Kong Polytechnic University Hong KongDepartment of Electrical Engineering Hong Kong Polytechnic University Hong Kong

w. report on the experimental obs.rvation of a novel type of tw.n-puls. s.liton in a pas.ively mode-locked fiber ring las.r. Tw.n-puls. s.liton interaction in the las.r cavity are als. experimentally inves.igated and ... 详细信息

关键词： Tw.n-Puls. s.liton Operation of a Fiber Las.r it on as of mode