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Science China Mathematics 2011年第8期54卷 1533-1545页

作者： BrIDSON Martin r. reeves Lawrence Mathematical Institute University of Oxford Department of Mathematics and Statistics University of Melbourne

We show that the isomorphism problem is solvable in the class of central extensions of word-hyperbolic groups,and that the isomorphism problem for biautomatic groups reduces to that for biautomatic groups with finite *** describe an algorithm that,given an arbitr.r. finite presentation of an automatic group Γ,will construct explicit finite models for the skeleta of K(Γ,1) and hence compute the integral homology and cohomology of Γ.

关键词： geometric group theory automatic groups isomorphism problem

Long—term sustainability of groundwater.r.sources： an approach using integrated hydrogeological and economic models

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Episodes 2003年第2期26卷 119-123页

作者： byP.A.White Y-S.Hong r.r.reeves InstituteofGeological&NuclearSciences PrivateBag2000TaupoNewZealand

Groundwater is an important but under-utilised water.r.source. Its use is growing. Approaches to the management of groundwater are evolving, with sustainability as the current approach in New Zealand, and other countries. Models of aquifer geometry, geology, groundwater flow, and groundwater quality are developed from observed data. These models are integrated using an economic model of groundwater use and groundwater quality to predict the total economic value of groundwater. This approach to modelling the sustainability of groundwater is demonstrated for the Delta Zone of the groundwater system in the Waimea Plains, Nelson, New Zealand. Four scenarios of use are investigated;actual, allocated, two-times allocated and five-times allocated. It is predicted that the economic value of irrigation from groundwater in the zone is $2 million with actual and allocated water usage. With use of two-times allocated, the economic value of irrigation from groundwater is $3.5 million. The Waimea river is predicted to be dry for at least one week in a dry year with this scenario. The economic value of irrigation from groundwater is -$1.3 million with water use of five times irrigation. This economic loss is due to land being taken out of production because of saltwater intrusion, and the costs of moving a water supply system caused by predicted saltwater intrusion. This research provides key information to assist the water management agency in setting allocation limits for groundwater.r.sources.

关键词：地下水水源成因长期持续性水文地质学经济模型水质

reports of a Possible Causal Link between Brain,Head,and Neck Tumors and radiation Exposure during Coronary Interventional Procedures:A Sobering Look at the Data

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Cardiovascular Innovations and Applications 2016年第B5期1卷 245-252页

作者： ryan r.reeves Ehtisham Mahmud Division of Cardiovascular Medicine Sulpizio Cardiovascular CenterUniversity of CaliforniaSan DiegoLa JollaCAUSA

radiation exposure is a hazard for patients and physicians during fluoroscopically-guided *** cardiologists are exposed to high levels of scatter.r.diation and both increasing procedural complexity and higher operator volumes contribute to exposure above recommended *** shielding does not offer suffi cient protection to the head and neck region and the potential for negative biological,subclinical,and clinical effects *** population studies suggest that cranial exposure to low dose radiation increases the risks of tumor *** addition,modest doses of therapeutic cranial radiation have been linked with the development of brain *** a causal association between scatter.r.diation in the cath lab and brain cancer does not currently exist,given the known detrimental effects of radiation exposure to the head and neck region support a focus on potential methods of protection for both the patient and the operator.

关键词： cardiac catheterization percutaneous coronary intervention invasive cardiology radiation exposure brain cancer

rabies in a postpandemic world:resilient reservoirs,redoubtable riposte,recurrent roadblocks,and resolute recidivism

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Animal Diseases 2023年第2期3卷 63-89页

作者： Charles E.rupprecht Philip P.Mshelbwala r.Guy reeves Ivan V.Kuzmin College of Forestry Wildlife&EnvironmentCollege of Veterinary MedicineAuburn UniversityAuburnAL 36849USA School of Veterinary Science University of QueenslandGattonAustralia Department of Veterinary Medicine Faculty of Veterinary MedicineUniversity of AbujaAbujaNigeria Max Planck Institut Fur Evolutionsbiologie 24306 PlonGermany Department of Pathology University of Texas Medical BranchGalvestonTX 77555USA

rabies is an ancient *** centuries since Pasteur,fundamental progress occurred in virology,vaccinology,and diagnostics—and an understanding of pathobiology and epizootiology of rabies in testament to One Health—before common terminological ***,control,selective elimination,and even the unthinkable—occasional treatment—of this zoonosis dawned by the twenty-first ***,in contrast to smallpox and rinderpest,eradication is a wishful misnomer applied to rabies,particularly post-COVID-19 *** are *** encompasses bats and mesocarnivores,but other mammals represent a diverse spectrum of potential *** rabies virus is the classical member of the genus,other species of lyssaviruses also cause the *** reservoirs remain *** global,this viral encephalitis is untreatable and often *** with other neglected diseases,laboratory-based surveillance falls short of the notifiable ideal,especially in lower-and middleincome *** of actual burden defaults to a flux within broad health economic *** priorities,lack of defined,long-term international donors,and shrinking local champions challenge human prophylaxis and mass dog vaccination toward targets of 2030 for even canine rabies *** prevention,all licensed vaccines are delivered to the individual,whether parenteral or oral–essentially‘one and done’.Exploiting mammalian social behaviors,future‘spreadable vaccines’might increase the proportion of immunized hosts per unit ***,the release of replication-competent,genetically modified organisms selectively engineered to spread intentionally throughout a population raises significant biological,ethical,and regulatory issues in need of broader,transdisciplinary *** this rather curious idea will evolve toward actual unconventional prevention,control,or elimination in the near term remains *** the interim,more precise terminology an

关键词： Diagnosis Epidemiology Lyssavirus Neglected Tropical Diseases Pathogenesis Prophylaxis rabies Surveillance Vaccination Zoonosis

Some insights into how barnacles survive as sessile organisms

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Integrative Zoology 2009年第4期4卷 395-401页

作者： John S.BUCKErIDGE Jessica M.reeves Earth and Oceanic Systems research Group RMIT UniversityMelbourneAustralia

During routine chemical analyses of the stalked ibliform barnacle Chaetolepas calcitergum Buckeridge&Newman 2006,peaks of more than 7%(by dry mass)of bromine were *** bromine ions occur in seawater(up to 66 ppm),this level of accumulation,in the soft tissue of the barnacle,is *** concentration of bromine compounds occurs in a number of invertebrates,such as algae and sponges,but this is the first record of elevated bromine in goose *** high accumulation of bromine compound(s)is most likely a defense *** present paper includes a review of the mechanisms deployed by barnacles to repel predators.

关键词： bromine Chaetolepas calcitergum Cirripedia defense mechanisms Ibliformes.

低交通量的国家——新西兰公路沿线土壤和植物中的铅污染

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环境科学动态 1989年第3期 14-18页

作者： N.I. Ward r.D. reeves r.r. Brooks 岳巍

已调查了经新西兰无人居住区的部份国家公路沿线的土壤和植物中的铅含量。研究地区距最北边的城镇20公里,其间横穿唯一的平均每天1200辆汽车的公路 (1973) 。植物样品的分析说明了,在距公路边100米内出现高的铅浓度,其近似地以距离的指... 详细信息

已调查了经新西兰无人居住区的部份国家公路沿线的土壤和植物中的铅含量。研究地区距最北边的城镇20公里,其间横穿唯一的平均每天1200辆汽车的公路 (1973) 。植物样品的分析说明了,在距公路边100米内出现高的铅浓度,其近似地以距离的指数函数的形式减少铅浓度。也在公路的100米内发现土壤中的高浓度的铅,而且其仅在5厘米的深度。铅含量超过土壤背景值的范围限于离公路250米和表土6厘米内,它由于汽油中加入四烷基铅,全部过往车辆排放铅的大部分。

关键词：土壤植物铅污染新西兰公路

Fractionation of platinum group elements in upper mantle: evidence from peridotite xenoliths from Wangqing

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Science China Earth Sciences 1998年第4期41卷 354-361页

作者：徐义刚 B.Orberger S.J.reeves Guangzhou Institute of Geochemistry Chinese Academy of Sciences Wushan China Laboratoire de Geochronologie Universite Paris 7 Paris France School of Earth Sciences University of Melbourne Parkville Victoria Australia

The peridotite xenoliths from Wangqing display a downward\|concave PGE pattern with Pt at maximum due to Pt-Pd fractionation, which is different from the flat or negatively sloped patterns commonly observed for worldwide peridotite xenoliths and massifs. Taking into account the difference in partition coefficients of Pt and Pd between alloy and sulfide melt, it is suggested that some of the Wangqing peridotites must have been equilibrated with a melt in which alloy and sulfide coexisted. Segregation of Pt-rich alloy from Pd-sulfide melts due to density contrast and extraction of residual melts without sulfide saturation resulted in the fractionation of Pt from Pd.

关键词： PGE geochemistry peridotite xenolith upper mantle Wangqing Jilin.

Thinning and in-stream wood recruitment in riparian second growth forests in coastal Oregon and the use of buffers and tree tipping as mitigation

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Journal of Forestry research 2016年第4期27卷 821-836页

作者： Lee E.Benda S.E.Litschert Gordon reeves robert Pabst TerrainWorks Mt. Shasta CA 96067 USA BLM National Operations Center Denver CO 80225-0047USA Pacific Northwest research Station U.S. Forest ServiceCorvallis OR 97331 USA Oregon State University Corvallis OR 97331 USA

Many aquatic habitats in coastal Oregon have been impacted by historic land use practices that led to losses of in-stream wood and associated degraded fish habitats. Many of these streams are now bordered by stands of dense second growth forests（30–80 years） that are incorporated into riparian buffer zones with low wood recruitment and storage. Thinning in riparian zones is one management option to increase the rate of large tree growth and eventually larger in-stream wood, however, it raises concern about impacts on current wood recruitment, among other issues. Using a forest growth simulation model coupled to a model of in-stream wood recruitment, we explore riparian management alternatives in a Douglas-fir plantation in coastal Oregon. Alternatives included：（1） no treatment,（2） single and double entry thinning, without and with a 10-m buffer, and（3） thinning combined with mechanical introduction of some portion of the thinned trees into the stream（tree tipping）. Compared to no treatment, single and double entry thinning on one side of a channel, without a 10-m buffer, reduce cumulative instream wood volume by 33 and 42 %, respectively, after100 years（includes decay）. Maintaining a 10-m buffer.r.duces the in-stream wood loss to 7 %（single entry thin）and 11 %（double entry）. To completely offset the losses of in-stream wood in a single entry thin（on one or both sides of the stream）, in the absence or presence of a 10-m buffer.r.quires a 12–14 % rate of tree tipping. relative to the notreatment alternative, cumulative in-stream wood storage can be increased up to 24 % in a double-entry thin with no buffer by tipping 15–20 % of the thinned trees（increased to 48 % if thinning and tipping simultaneously on both sides of the stream）. The predicted increases in in-stream wood that can occur during a thin with tree tipping may be effective for.r.storing fish habitat, particularly in aquatic systems that have poor habitat conditions and low levels of in-stream wood due to h

关键词： thinning mitigation coastal Oregon forests habitat piece plantation stands cumulative

Direct numerical simulation of matrix diffusion across fracture/matrix interface

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Water Science and Engineering 2013年第4期6卷 365-379页

作者： Yong ZHANG Eric M.LABOLLE Donald M.reeves Charles rUSSELL Division of Hydrologic Sciences Desert Research Institute Department of Land Airand Water ResourcesUniversity of California

Accurate descriptions of matrix diffusion across the fracture/matrix interface are critical to assessing contaminant migration in fractured media. The classical transfer probability method is only applicable for.r.latively large diffusion coefficients and small fracture spacings, due to an intrinsic assumption of an equilibrium concentration profile in the matrix blocks. Motivated and required by practical applications, we propose a direct numerical simulation （DNS） approach without any empirical assumptions. A three-step Lagrangian algorithm was developed and validated to directly track the particle dynamics across the fracture/matrix interface, where particle＇s diffusive displacement across the discontinuity is controlled by an analytical, one-side reflection probability. Numerical experiments show that the DNS approach is especially efficient for small diffusion coefficients and large fracture spacings, alleviating limitations of the classical modeling approach.

关键词： Key words: fracture matrix interface direct numerical simulation transfer probability Lagrangian algorithm