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A weak formulation of heterogenous viscoacoustic wave propagation in infinite domain

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earthquake engineering and engineering Vibration 2025年第1期24卷 31-51页

作者： Xie Zhinan Zheng Yonglu paul Cristini Alexis Bottero Shan Zhendong Lu Jianqi Zhang Xubin Key Laboratory of earthquake engineering and engineering Vibration Institute of Engineering MechanicsChina Earthquake AdministrationKey Laboratory of Earthquake Disaster MitigationMinistry of Emergency ManagementHarbin 150080China Laboratoire de Mecanique et d’Acoustique du CNRS Aix Marseille Univ.CNRSMarseille F-13353France Marine Physical Laboratory Scripps Institution of OceanographyUniversity of CaliforniaSan Diego 92093USA

The accurate simulation of wave propagation in real media requires properly taking the attenuation into account,which leads to wave dissipation together with its causal companion,wave *** this study,to obtain a weak formulation of heterogenous viscoacoustic wave propagation in an infinite domain,the viscoacoustic medium is first characterized by its frequency-dependent complex bulk compliance instead of the classically used complex bulk ***,a mechanical model using serially connected standard linear solids(SSLS)is built to obtain the rational approximation of the complex bulk compliance whose parameters are calculated via an adapted nonlinear optimization *** the obtained bulk compliance-based constitutive relation,a novel second-order viscoacoustic wave equation in the frequency domain is derived,of which the weak formulation can be physically explained as the virtual work equation and can thus be discretized using a continuous spectral element method in ***,a new method is introduced to address the convolution terms involved in the inverse Fourier transform,whose accurate time integration can then be achieved using an explicit time scheme,which avoids the transient growth that exists in the classical *** resulting full time-space decoupling scheme can handle wave propagation in arbitrary heterogeneous ***,to treat the wave propagation in an infinite domain,a perfectly matched layer in weak formulation is derived for the truncation of the infinite domain via complex coordinate stretching of the virtual work *** only minor modification,the resulting perfectly matched layer can be implemented using the same time scheme as for the wave equation inside the truncated *** accuracy,numerical stability,and versatility of the new proposed scheme are demonstrated with numerical examples.

关键词： viscoacoustic wave standard linear solid complex bulk compliance heterogenous media perfectly matched layer Legendre spectral element method

Assessing habitat quality of the mountain nyala Tragelaphus buxtoni in the Bale Mountains, ethiopia

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Current Zoology 2012年第4期58卷 525-535页

作者： paul H. eVANGeLISTA John norman III paul SWARTZINKI3,paul SWARTZINKI3,paul SWARTZINKI Nicholas e. YOUNG Natural Resource ecology Laboratory Colorado State University Fort Collins CO 80524-1499 USA Natural Resource Conservation Service Shepardson Bldg. Colorado State University Fort Collins CO 80524 USA AeCOM 1601 Prospect Pkwy Fort Collins CO 80303 USA

Populations of the endangered mountain nyala Tragelaphus buxtoni are significantly threatened by the loss of critical habitat. Population estimates are tentative, and information on the species＇ distribution and available habitat is required for for-mulating immediate management and conservation strategies. To support management decisions and conservation priorities, we integrated information from a number of small-scale observational studies, interviews and reports from multiple sources to define habitat parameters and create a habitat quality model for mountain nyala in the Bale Mountains. For our analysis, we used the FunConn model, an expertise-based model that considers spatial relationships （i.e., patch size, distance） between the species and vegetation type, topography and disturbance to create a habitat quality surface. The habitat quality model showed that approxi- mately 18,610 km^2 （82.7% of our study area） is unsuitable or poor habitat for the mountain nyala, while 2,857 km^2 （12.7%） and 1,026 km^2 （4.6%） was ranked as good or optimal habitat, respectively. Our results not only reflected human induced habitat deg-radation, but also revealed an extensive area of intact habitat on the remote slopes of the Bale Mountain＇s southern and southeast- ern escarpments. This study provides an example of the roles that expert knowledge can still play in modem geospatial modeling of wildlife habitat. New geospatial tools, such as the FunConn model, are readily available to wildlife managers and allow them to perform spatial analyses with minimal software, data and training requirements. This approach may be especially useful for species that are obscure to science or when field surveys are not practical .

关键词： expert knowledge FunConn model Habitat mapping Land cover Mountain nyala Wildlife conservation

Prognostic Factors for Operated Traumatic Brain Injury at the Yaounde emergency Center

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Open Journal of Modern Neurosurgery 2025年第1期15卷 88-95页

作者： ernestine Renée Bikono Atangana Alain Jibia Serge Rawlings Ngouatna Reid Achu Darius Kenzo Temgoua Herve Mfouapon ewane Casimir Fankem Vincent de paul Djientcheu Faculty of Medicine and Biomedical Sciences University of Yaounde I Yaounde Cameroon Neurosurgery Department Yaounde Central Hospital Yaounde Cameroon Faculty of Medicine and Biomedical Sciences University of Garoua Garoua Cameroon Yaounde emergency Center Yaounde Cameroon

Introduction: Head injuries constitute a public health problem in Cameroon and everywhere else in the world. They represent 23% of admissions to the Yaounde emergency center (CURY), which is a center exclusively dedicated, since 2014, to emergency care in Yaounde. In the management of trauma brain injuries at CURY, several are operated on. However, to date, no evaluation of these operated patients has yet been made. Goals: The objective of this study was to highlight the prognostic factors in patients operated for TBI at CURY. Methodology: We conducted a descriptive study whose data collection was done retrospectively over 2 years (01 January 2021 to 31 December 2022) at CURY. Data was collected from the registers of operative reports. Results: We enrolled 105 medical reports of patients who were victims of TBI operated on. The male gender predominated with a sex ratio of 3/1. The average age of the patients was 37.5 ± 18.83 years. Public road accidents were the leading cause of TBI in 75.2% of cases. The means of transport of the victims were mostly non-medical 97.1%. 45.7% of patients were admitted in less than 6 hours following injury. The initial clinical evaluation found 45.8% of patients with a Glasgow Coma Score (GCS) between [14, 15], and 13.2% of patients had a GCS 8. The indications for surgery were extradural hematoma (30%), followed by acute subdural hematoma (24%). The major complication was postoperative infection (25%). The mortality rate of the series was 7.9%. Poor prognostic factors were the depth of the coma on admission, advanced age and postoperative complications. Conclusion: The results of this study suggest that most patients operated on for TBI at CURY had a favorable outcome. The poor prognostic factors were the depth of the coma on admission, advanced age, postoperative complications and comorbidities.

关键词： Operated TBI Prognosis Yaounde emergency Center

A Framework for Assessing Import Costs of Medical Supplies and Results for a Tuberculosis Program in Karakalpakstan,Uzbekistan

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Health Data Science 2021年第1期2021卷 120-132页

作者： Stefan Kohler norman Sitali Nicolas paul Heidelberg Institute of Global Health Faculty of Medicine and University HospitalHeidelberg UniversityHeidelbergGermany Médecins Sans Frontières BerlinGermany Institute of Social Medicine Epidemiology and Health EconomicsCharité–Universitätsmedizin Berlincorporate member of Freie Universität Berlin and Humboldt-Universität zu BerlinBerlinGermany

*** of medical supplies is common,but limited knowledge about import costs and their structure introduces uncertainty to budget planning,cost management,and cost-effectiveness analysis of health *** aimed to estimate the import costs of a tuberculosis(TB)program in Uzbekistan,including the import costs of specific imported *** developed a framework that applies costing and cost accounting to import ***,transport costs,customs-related costs,cargo weight,unit weights,and quantities ordered were gathered for a major shipment of medical supplies from the Médecins Sans Frontières(MSF)Procurement Unit in Amsterdam,the Netherlands,to a TB program in Karakalpakstan,Uzbekistan,in ***,air freight,land freight,and customs clearance cost totals were ***,total import costs were allocated to different cargos(standard,cool,and frozen),items(e.g.,TB drugs),and units(e.g.,one tablet)based on imported weight and *** sources were order invoices,waybills,the local MSF logistics department,and an MSF standard product *** shipment contained 1.8 million units of 85 medical items of standard,cool,and frozen *** average import cost for the TB program was 9.0%of the shipment *** cost varied substantially between cargos(8.9–28%of the cargo value)and items(interquartile range 4.5–35%of the item value).The largest portion of the total import cost was caused by transport(82–99%of the cargo import cost)and allocated based on imported ***(14%)of the 69 items imported as standard cargo were associated with 85%of the standard cargo import *** cargo items could be grouped based on contributing to import costs predominantly through unit weight(e.g.,fluids),imported quantity(e.g.,tablets),or the combination of unit weight and imported quantity(e.g.,items in powder form).*** cost of importing medical supplies to a TB program in Karakalpakstan,Uzbekistan,was sizable,variable,an

关键词： imported items cargo

Heterogeneous occurrence of evergreen broad-leaved forests in east Asia:evidence from plant fossils

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Plant Diversity 2025年第1期47卷 1-12页

作者： Jiagang Zhao Shufeng Li Jian Huang Wenna Ding Mengxiao Wu Tao Su Alexander Farnsworth paul J.Valdes Linlin Chen Yaowu Xing Zhekun Zhou CAS Key Laboratory of Tropical Forest ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China University of Chinese Academy of Sciences Beijing 100049China Swiss Federal Institute for Forest Snow and Landscape Research WSL8903 BirmensdorfSwitzerland Senckenberg Natural History Collections Dresden Koonigsbrücker Landstraße 15901109 DresdenGermany State Key Laboratory of Oil and Gas Reservoir Geology and exploitation&Institute of Sedimentary Geology Chengdu University of TechnologyChengdu 610059China School of Geographical Sciences University of BristolBristol BS81SSUK State Key Laboratory of Tibetan Plateau earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

evergreen broad-leaved forests(eBLFs) are widely distributed in east Asia and play a vital role in ecosystem stability. The occurrence of these forests in east Asia has been a subject of debate across various disciplines. In this study, we explored the occurrence of east Asian eBLFs from a paleobotanical perspective. By collecting plant fossils from four regions in east Asia, we have established the evolutionary history of eBLFs. Through floral similarity analysis and paleoclimatic reconstruction, we have revealed a diverse spatio-temporal pattern for the occurrence of eBLFs in east Asia. The earliest occurrence of eBLFs in southern China can be traced back to the middle eocene, followed by southwestern China during the late eocene-early Oligocene. Subsequently, eBLFs emerged in Japan during the early Oligocene and eventually appeared in central-eastern China around the Miocene. Paleoclimate simulation results suggest that the precipitation of wettest quarter(PWet Q, mm) exceeding 600 mm is crucial for the occurrence of eBLFs. Furthermore, the heterogeneous occurrence of eBLFs in east Asia is closely associated with the evolution of the Asian Monsoon. This study provides new insights into the occurrence of eBLFs in east Asia.

关键词： evergreen broad-leaved forests(eBLFs) Plant fossils east Asia Paleoclimate Paleovegetation Asian monsoon

Transitioning from paternalism to empowerment of farmers in lowincome countries: Farming components to systems

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Journal of Integrative Agriculture 2015年第8期14卷 1490-1499页

作者： David norman Agricultural economics Department Kansas State University

Reasons for the initiation of farming systems/participatory approaches in non-Green Revolution（i.e., in more heterogeneous and less favourable production environments） areas in low-income countries is followed by a discussion of their *** phases are described along, with a brief description of some of the significant methods in which farmer participation has been sought, accessed and *** enabled/facilitated the evolutionary ***, over the last 40 years there has been a progress in making small-scale farmers much more visible in driving the agricultural research/development agenda through using the four basic stages embodied in the farming systems approach（i.e., descriptive, diagnosis, testing/evaluation and finally dissemination）, much still needs to be *** leads on to a discussion as to some of the barriers still inhibiting true farmer empowerment and why further, such empowerment is imperative, if the agricultural challenges of this century are to be addressed successfully, namely substantially increasing agricultural productivity in an ecologically sustainable *** the heterogeneity of the production environments and that many identified improvements are likely to be incremental rather than revolutionary in nature, this will require farmers＇ intimate involvement in their identification, evaluation and *** in the paper recognizes that there is increasing globalization/commercialization of agriculture and is predicated on the need to consider the whole farmer-research-development continuum involving multiple stakeholders（i.e., farmers, scientists, extension workers, input/output service providers and policymakers）.Such a continuum has been explicitly recognized in the operational plans for the recently reformed international agricultural research（i.e., CGIAR） *** paper concludes with a short discussion on the potential role of formal modelling.

关键词： farming systems research farmer empowerment farmer participatory approaches/techniques globalisation commercialisation conservat

筛查腹主动脉瘤死亡率的作用:基于人群的随机对照试验

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英国医学杂志中文版 2005年第2期8卷 131-131页

作者： paul e norman Konrad Jamrozik Michael M Lawrence-Brown Max T Q Le Carole A Spencer Raywin J Tuohy Richard W Parsons James A Dickinson 王世贤

目的：评价筛查男性腹主动脉瘤能否减少其死亡率。设计：基于人群的随机对照试验，行超声检查，分析患者年龄标化死亡率。地点：澳洲西部，基于社区的筛查项目。参加者：65-83岁的男性41000人，随机分为干预组和对照组。

关键词：随机对照试验腹主动脉瘤筛查人群标化死亡率超声检查患者年龄对照组男性

evolving landscape and novel treatments in, metastatic castrate-resistant prostate cancer

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Asian Journal of Andrology 2013年第3期15卷 342-349页

作者： paul J Toren Martin e Gleave Department of Urologic Sciences Faculty of Medicine University of British Columbia Vancouver BC V5Z 1M9 Canada

Treatment options for castrate-resistant prostate cancer （CRPC） have advanced in recent years and significantly improved the Outlook for patients with this aggressive and lethal disease. Further understanding of the biology＇of CRPC has led to several new targeted therapies and continues to emphasize the importance of androgen receptor （AR） directed therapy. The treatment landscape is rapidly changing and further biologically rationale, biomarker-based ongoing clinical trials are needed. We review the recent results of major clinical trials in CRPC. New and investigational agents now in clinical evaluation are reviewed including inhibitors of angiogenesis, microtubules, chaperones, AR and intracellular kinases, as well as immunotherapy, radiopharmaceuticals and bone-targeted agents. The recent improvement in prognosis for CRPC brings continued optimism for further improvements. Thoughtful planning of clinical trials and further understanding of the mechanisms of resistance to therapies will allow for continued progress in patient care.

关键词： prostate cancer treatment resistance androgen receptor antagonists molecular targets

AN ANALYSIS oF THe SHeAR FAILURe OF RIGID-LINeAR HARDeNING BeAMS UNDeR IMPULSIVe LOADING

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Acta Mechanica Sinica 1996年第4期12卷 338-348页

作者：王礼立 norman Jones Ningbo University Ningbo 315211China and also University of Science and Technology of ChinaHefei 230026China Impact Research Centre Department of Mechanical EngineeringUniversity of Liverpool.P.O.Box 147Liverpool L69 3BXU.K.

A theoretical rigid-plastic analysis for the dynamic shear failure of beams under impulsive loading is presented when using a travelling plastic shear hinge model which tabes into account material strain hardening. The maximum dynamic shear strain and shear strain-rate can be predicted in addition to the permanent transverse deflections and other parameters. The conditions for the three modes of shear failure, i.e., excess deflection failure, excess shear strain failure and adiabatic shear failure are analyzed. The special case of an infinitesimally small plastic zone is discussed and compared with Nonaka's solution for a rigid, perfectly plastic material. The results can also be generalized to examine the dynamic response of fibre-reinforced beams.

关键词： shear failure rigid-linear hardening plastic beam dynamic response impulsive loading adiabatic shear