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利用模拟和分析历史资料的方法根据《欧洲水框架指令》评价参考条件:以丹麦兰讷斯峡湾为例

AMBIO－人类环境杂志 2003年第4期32卷 287-294页

作者： Kurt Nielsen bent sφmod Christina Ellegaard Dorte Krause-Jensen 林宝法国家环境研究所研究部

《欧洲水框架指令》(WFD)要求确定所有地表水的参考条件,即原始条件。鉴于丹麦沿岸水域的目前状态不能被称为是原始的,因此,必须通过分析历史资料或利用模型来评价参考条件。以兰讷斯峡湾为例,本文的目的是:①论证通过历史资料和模拟评... 详细信息

《欧洲水框架指令》(WFD)要求确定所有地表水的参考条件,即原始条件。鉴于丹麦沿岸水域的目前状态不能被称为是原始的,因此,必须通过分析历史资料或利用模型来评价参考条件。以兰讷斯峡湾为例,本文的目的是:①论证通过历史资料和模拟评价参考条件的可能性和限制因素;②论证生态条件是如何随着富营养化而改变的,来自兰讷斯峡湾的充分历史资料使我们能够评价与底栖大型植物和底栖动物有关的参考条件。具有不同复杂性的模型使我们能够评价营养物质、叶绿素α、透明度板深度以及大叶藻等的参考条件。我们断定,模型是评价参考条件的有益补充,尽管它们目前由于缺乏富营养化和物种组成之间的定量联系而受到限制。

关键词：模拟评价历史资料《欧洲水框架指令》丹麦兰讷斯峡湾生态条件富营养化物种

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Verdier quotients of homotopy categories of rings and Gorenstein-projective precovers

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science China Mathematics 2024年

作者： Manuel Cortés-Izurdiaga Departamento de Matemática Aplicada Universidad de Málaga

Let R be a ring, Proj be the class of all the projective right R-modules, K be the full subcategory of the homotopy category K(Proj) whose class of objects consists of all the totally acyclic complexes, and MorK be the class of all the morphisms in K(Proj) whose cones belong to K. We prove that if K(Proj) has enough MorK-injective objects, then the Verdier quotient K(Proj)/K has small Hom-sets, and this last condition implies the existence of Gorenstein-projective precovers in mod-R and of totally acyclic precovers in C(mod-R).

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Recovery of bird communities following the construction of a large-scale hydroelectric dam

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Ecological Processes 2021年第1期10卷 408-417页

作者： Affan Nasruddin-Roshidi Mohammad saiful Mansor Nor Adibah Ismail Ehwan Ngadi Mohd Izzat-Husna shahril mod Husin Farah shafawati Mohd-Taib Rahmah Illias shukor Md Nor Department of Biological sciences and Biotechnology Faculty of Science and TechnologyUniversiti Kebangsaan Malaysia43600 BangiSelangorMalaysia Kolej GENIUs Insan Universiti Sains Islam MalaysiaBandar Baru Nilai71800 NilaiNegeri SembilanMalaysia TNB Research sdn Bhd No.1Kawasan Institusi PenyelidikanJalan Ayer Itam43000 KajangSelangorMalaysia Department of Wildlife and National Parks(PERHILITAN) Km.10Jln Cheras56100 Kuala LumpurWilayah PersekutuanMalaysia.

Background:Habitat degradation is known to have a major impact on the composition of bird communities,yet how these communities recover following such disturbance is less *** study examined bird community changes from pre-logging to recovery over the course of habitat disturbance caused by the development of the Hulu Terengganu Hydroelectric Dam Project in Peninsular Malaysia,between 2007 and *** surveys were conducted using point count observations and mist netting in the dam area from the prelogging phase until the operation ***:It was observed that while bird species significantly declined after large-scale habitat clearance between the pre-logging and construction phases,they showed positive signs of recovery from the inundation to operation *** findings indicate that the bird community is still recovering,and the permanent loss of habitat required by most of the original species has not occurred,as evidenced by *** species composition differed across phases due to varying habitat *** turnover rate and immigration rate(recolonisation and newly recorded species)were higher between the construction and operation *** was also observed that insectivorous birds were more heavily affected than others by changes to the landscape,which highlights the versatility,survivability and tolerance of certain species to extreme disturbance and habitat ***:Although the operation phase showed an incremental change in bird species richness due to recolonisation and newly recorded species,this value remains far from that of the pre-logging *** predict that bird species recovery will continue to increase for some time before reaching a plateau among the newly created islands,reservoir and catchment area of the dam.

关键词： Dam construction Extinction Habitat recovery Recolonisation Turnover

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TYPE I REPREsENTATIONs OF (QUANTUM ALGEBRA H_q(4) FOR q-OsCILLATORs sYsTEM

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Acta Mathematica scientia 1993年第4期13卷 406-412页

作者：李康 Zhejiang Inst. of mod. Phys. Zhejiang Univ Hangzhou 310027 Dept. of Phys. Yana'n Univ. Yan'an 716000 China

After giving a brief review of H(4) and sU(2) quantum algebras and their relationship, Ⅰ work out the type Ⅰ representations of H(4) quantum algebra for the case q being a root of unity, these representations are re... 详细信息

关键词： Q-ANALOGs HARMONIC-OsCILLATOR

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High birth weight is a risk factor of dental caries increment during adolescence in sweden

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Open Journal of stomatology 2013年第9期3卷 42-51页

作者： Annika Julihn Ulrika Molund Emma Drevsater Thomas modéer Division of Pediatric Dentistry Department of Dental MedicineKarolinska InstituteHuddingeSweden specialist Clinic of Pediatric Dentistry Specialist Dental Care in Vastra GotalandGoteborgSweden

This study aimed to assess whether birth weight is associated with dental caries during the teenage period. In this register-based cohort study, all children of 13 yrs of age (n = 18,142) who resided in the county of stockholm, sweden, in 2000 were included. The cohort was followed until individuals were 19 yrs of age. Information regarding dental caries was collected from the Public Health Care Administration in stockholm. Data concerning prenatal and perinatal factors and parental socio-demographic determinants were collected from the swedish Medical Birth Register and National Registers at statistics sweden. The final logistic regression model showed that birth weight (≥4000 g), adjusted for potential confounders, was significantly associated with caries increment (DMFT ≥ 1) between 13 and 19 yrs of age (OR: 1.29, 95% CI = 1.13 - 1.48). The relatively enhanced risk OR was further increased from 1.29 to 1.52 in sub- jects with birth weight (≥4600 g). On the contrary, subjects with birth weight (sig- nificantly lower risk (OR: 0.67, 95% CI = 0.50 - 0.89) for exhibiting caries experience (DMFT ≥4) at 19 yrs of age. In conclusion, birth weight can be regarded as a predictor for dental caries and birth weight (≥4000 g) is especially a risk factor for caries increment during adolescence.