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Selected AbstractsEffect of soil interaction on the performance of liquid column dampers for seismic applicationsEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 11 2005Aparna Ghosh Abstract The effects of soil,structure interaction (SSI) while designing the liquid column damper (LCD) for seismic vibration control of structures have been presented in this study. The formulation for the input,output relation of a flexible-base structure with attached LCD has been presented. The superstructure has been modelled by a single-degree-of-freedom (SDOF) system. The non-linearity in the orifice damping of the LCD has been replaced by equivalent linear viscous damping by using equivalent linearization technique. The force,deformation relationships and damping characteristics of the foundation have been described by complex valued impedance functions. Through a numerical stochastic study in the frequency domain, the various aspects of SSI on the functioning of the LCD have been illustrated. A simpler approach for studying the LCD performance considering SSI, using an equivalent SDOF model for the soil,structure system available in literature by Wolf (Dynamic Soil,Structure Interaction. International Series in Civil Engineering and Engineering Mechanics. Prentice-Hall: Englewood Cliffs, NJ, 1985) has also been presented. Copyright © 2005 John Wiley & Sons, Ltd. [source] MHC studies in nonmodel vertebrates: what have we learned about natural selection in 15 years?JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2003L. Bernatchez Abstract Elucidating how natural selection promotes local adaptation in interaction with migration, genetic drift and mutation is a central aim of evolutionary biology. While several conceptual and practical limitations are still restraining our ability to study these processes at the DNA level, genes of the major histocompatibility complex (MHC) offer several assets that make them unique candidates for this purpose. Yet, it is unclear what general conclusions can be drawn after 15 years of empirical research that documented MHC diversity in the wild. The general objective of this review is to complement earlier literature syntheses on this topic by focusing on MHC studies other than humans and mice. This review first revealed a strong taxonomic bias, whereby many more studies of MHC diversity in natural populations have dealt with mammals than all other vertebrate classes combined. Secondly, it confirmed that positive selection has a determinant role in shaping patterns of nucleotide diversity in MHC genes in all vertebrates studied. Yet, future tests of positive selection would greatly benefit from making better use of the increasing number of models potentially offering more statistical rigour and higher resolution in detecting the effect and form of selection. Thirdly, studies that compared patterns of MHC diversity within and among natural populations with neutral expectations have reported higher population differentiation at MHC than expected either under neutrality or simple models of balancing selection. Fourthly, several studies showed that MHC-dependent mate preference and kin recognition may provide selective factors maintaining polymorphism in wild outbred populations. However, they also showed that such reproductive mechanisms are complex and context-based. Fifthly, several studies provided evidence that MHC may significantly influence fitness, either by affecting reproductive success or progeny survival to pathogens infections. Overall, the evidence is compelling that the MHC currently represents the best system available in vertebrates to investigate how natural selection can promote local adaptation at the gene level despite the counteracting actions of migration and genetic drift. We conclude this review by proposing several directions where future research is needed. [source] Benzodiazepines and injury: a risk adjusted model,,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 1 2005Dustin D. French MA Abstract Background Benzodiazepines (BZD) are one class of medications that are generally acknowledged to be a risk factor for injuries. Objective Our objective was to link outpatient prescription data with clinical data in order to develop a risk adjusted binary model that associates BZD usage with the risk for a healthcare encounter for an injury. Methods In total, 3 years of outpatient BZD prescription data, totaling 133,872 outpatient BZD prescriptions for 13,745 patients for a VA medical center, were combined with data from inpatient and outpatient administrative databases. The model incorporated Elixhauser comorbidity measures with 1-year look back period, along with hospital discharges, marital status, age, mean arterial pressure and body mass index. The model also included the dose of the drug, converted to valium equivalents and its duration. The model was analyzed using generalized estimation equations (GEE). Results Dose, duration, discharges and various comorbidities were associated with an increased risk for injury, while being married reduced the risk. Increased body mass was associated with increased injury risk. Increased mean arterial pressure was associated with decreased risk. Conclusions These findings offer guidance on how specific combinations of risk factors and potential protective effects may impact accidental injury risk. Clinicians prescribing or adjusting BZDs can use these results to more accurately tailor medication regimens for a patient. Our findings suggest that clinicians should also consider the nature of the social support system available to the patient in assessing total injury risk. Copyright © 2004 John Wiley & Sons, Ltd. [source] Execution models for reconfigurable embedded real-time systems,ASIAN JOURNAL OF CONTROL, Issue 3 2009Mohamed Khalgui Abstract This paper deals with the verification and assignment into the execution environment of Reconfigurable Control Applications following the Component-based International Industrial Standard IEC61499. According to this Standard, a Function Block (FB) is an event-triggered component and an application is an FB network that has to meet temporal properties according to user requirements. If a reconfiguration scenario is applied at run-time, then the FB network implementing the application is totally changed or modified. To cover all possible cases, we classify such scenarios into three classes and we define an agent-based architecture designed with nested state machines to automatically handle all possible reconfigurations. To verify and assign Function Blocks corresponding to each reconfiguration scenario into the execution environment, we define an approach based on the exploration of reachability graphs to verify temporal properties. This approach constructs feasible Operating System tasks encoding the FB network that corresponds to each scenario. Therefore, the application is considered as sets of Operating System (OS) tasks where each set is to load in memory when the corresponding reconfiguration scenario is applied by the agent. We developed the tool X - Assign supporting these contributions that we apply on the FESTO production system available in our research laboratory. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source] Supply of inpatient geriatric medical services in AustraliaINTERNAL MEDICINE JOURNAL, Issue 4 2007L. Gray Abstract This study summarizes the findings of a national survey of inpatient geriatric services in Australia conducted in 2001. These data are unique as there are no uniform administrative data systems available to provide this information. Eight hundred and eighty-eight hospitals were surveyed and full responses were received from 690, representing 78% of hospitals and 85% of all hospital beds. The results illustrated wide variation in the style and level of provision of services among hospitals and across regional and state jurisdictions. [source] Are primary cultures realistic models of prostate cancer?JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 1 2004Donna M. Peehl Abstract Primary cultures fill a unique niche among the repertoire of in vitro model systems available to investigate the biology of the normal and malignant human prostate. This review summarizes some of the properties of primary cultures, with special emphasis on two questions: are primary cultures from adenocarcinomas really comprised of cancer rather than normal cells, and do primary cultures faithfully retain characteristics of cells of origin? © 2003 Wiley-Liss, Inc. [source] A computer-assisted test design and diagnosis system for use by classroom teachersJOURNAL OF COMPUTER ASSISTED LEARNING, Issue 6 2005Q. He Abstract Computer-assisted assessment (CAA) has become increasingly important in education in recent years. A variety of computer software systems have been developed to help assess the performance of students at various levels. However, such systems are primarily designed to provide objective assessment of students and analysis of test items, and focus has been mainly placed on higher and further education. Although there are commercial professional systems available for use by primary and secondary educational institutions, such systems are generally expensive and require skilled expertise to operate. In view of the rapid progress made in the use of computer-based assessment for primary and secondary students by education authorities here in the UK and elsewhere, there is a need to develop systems which are economic and easy to use and can provide the necessary information that can help teachers improve students' performance. This paper presents the development of a software system that provides a range of functions including generating items and building item banks, designing tests, conducting tests on computers and analysing test results. Specifically, the system can generate information on the performance of students and test items that can be easily used to identify curriculum areas where students are under performing. A case study based on data collected from five secondary schools in Hong Kong involved in the Curriculum, Evaluation and Management Centre's Middle Years Information System Project, Durham University, UK, has been undertaken to demonstrate the use of the system for diagnostic and performance analysis. [source] Fabrication of Direct Fiber-Reinforced Posts: A Structural Design ConceptJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 4 2001DOUGLAS A. TERRY DDS ABSTRACT As the clinician continues the quest for optimal functional and esthetic success of a tooth-restorative complex, the current selection of restorative materials and techniques may prove overwhelming. Although no single system provides the ideal restorative solution for every clinical circumstance, understanding of general design criteria and the components for the various post and core systems available allow the clinician to appropriately select the method and materials compatible with the existing tooth structure and desired result. This article provides a discussion of the various post and core systems, the methods and materials inherent in these systems, and general design principles. Using that basic information and clinical experience, the authors offer an alternative procedure for the rehabilitation of the intraradicular anatomy of the post-endodontic channel with a direct composite resin,the fiber-reinforced post and core system. CLINICAL SIGNIFICANCE Using improved restorative materials that simulate the physical properties and other characteristics of natural teeth in combination with the proper design principles, the clinician can develop a tooth-restorative complex with optimal functional and esthetic results. [source] A national survey of computerized decision support systems available to nurses in EnglandJOURNAL OF NURSING MANAGEMENT, Issue 7 2009NATASHA MITCHELL PhD Aim, To examine the characteristics of computerized decision support systems (CDSS) currently available to nurses working in the National Health Service (NHS) in England. Method, A questionnaire survey sent to a stratified random sample of 50% of all NHS care providers (Trusts) in England, asking respondents to provide information on CDSS currently used by nurses. Results, Responses were received from 108 of the 277 Trusts included in the sample. Electronic patient record systems were the most common type of CDSS reported by Trusts (n = 61) but they were least likely to have features that have been associated with improved clinical outcomes. Conclusions, The availability of CDSS with features that have been associated with improved patient outcomes for nurses in the NHS in England is limited. There is some evidence that the nature of the Trust affects whether or not nurses have access to CDSS to assist their decision making. Implications for nursing management, The implementation of CDSS is increasing throughout the NHS. Many CDSS are introduced without adequate evidence to support its introduction and there is little evaluation of the benefits once they are implemented. Policy makers and nursing management should consider whether the introduction of CDSS aids nurse decision making and benefits patient outcomes. [source] Regulation of tumor dormancy as a function of tumor-mediated paracrine regulation of stromal Tsp-1 and VEGF expression,APMIS, Issue 7-8 2008SOO-YOUNG KANG Tumor dormancy is a critical yet poorly understood phenomenon affecting both the diagnosis and treatment of human cancers. This is due in large part to the lack of model systems available to study dormant tumor cells and the length of time needed to adequately examine the models that do exist. It has been demonstrated in several types of human cancer that tumor dormancy is a function of an impairment in angiogenesis. The intracellular signaling pathways regulating the expression of several pro- and anti-angiogenic proteins have been well characterized in human cancer cells. The intercellular signaling that takes place between tumor cells and the surrounding tumor-associated stroma has not been as extensively studied with regard to the regulation of angiogenesis, and as a result dormancy. In this review we define the key players in the regulation of angiogenesis and examine how their expression is regulated in the tumor-associated stroma. The resulting analysis is often seemingly paradoxical, underscoring the complexity of intercellular signaling within tumors and the need to better understand the environmental context underlying these signaling mechanisms. [source] An evaluation of the role of a store-and-forward teledermatology system in skin cancer diagnosis and managementCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 3 2005R. Mahendran Summary There is currently much interest in the potential role of telemedicine in improving the delivery of dermatological care in the UK. The two teledermatology systems available at present are divided into live video and store-and-forward technology. We investigated the value of a store-and-forward teledermatology system in the diagnosis and management of lesions suspicious of skin cancer. A total of 163 store-and-forward referrals of patients with one lesion each were assessed independently by a Consultant and a third-year trainee dermatologist. The accuracy of diagnosis and appropriateness of management from these assessments was compared to a subsequent face-to-face consultation with the Consultant. Analysis of the Consultants' diagnoses showed that 48% were identical for teledermatology and conventional face-to-face consultations. A further 17% of teledermatology diagnoses included the actual clinical diagnosis as a possibility but 20% were either incorrect or a diagnosis could not be made. In the remaining 15% of cases the digital image was of insufficient quality for assessment. Of the trainee's reports, 44% were identical to the clinical diagnoses and another 20% included the clinical diagnosis as a possibility. The management plan was appropriate in 55% of the total teledermatology referrals assessed by the Consultants and in 52% assessed by the trainee when compared with the conventional consultation. This study illustrates that the store-and forward type telemedicine system has limited diagnostic accuracy for skin lesions. However, our results suggest that store-and-forward teledermatology may be suitable and safe for screening out clearly benign lesions but the study casts doubt on its efficiency. [source] | ||||||||||||||||