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Selected AbstractsManagement Strategies and Improvement of Performance of Sewer NetworksCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 7 2007Denys Breysse Even when they are conscious about the needs of maintenance to keep the system in a good condition, they lack efficient methods and tools that may help them in taking appropriate decisions. One can say that no really satisfactory and efficient tool exists, enabling the optimization of Inspection, Maintenance, or Rehabilitation (IMR) strategies on such systems. Sewer managers and researchers have been involved for many years in the French National Research Project for Renewal of Non Man Entry Sewer System (RERAU,Réhabilitation des Réseaux d'Assainissement Urbains, in French) to improve their knowledge of these systems and the management policies. During the RERAU project, a specific action has been dedicated to the modeling of asset ageing and maintenance. A special attention has been dedicated to the description of defects and dysfunctions, to the evaluation of performances and its modeling, accounting for its various dimensions (from the point of view of the manager, of the user, of the environment,). After having defined an Index of Technical Performance (ITp), we will introduce the Index of Technical and Economic Performance (ITEp) that is a combined measure of performance (including social costs) and technical costs. This index provides an objective standard tool for managers to compare different alternatives. It is used in the article to compare some simple IMR strategies. It sets the basis of a new method for no-man entry sewer system management, enabling us to analyze the profitableness of investment in terms of both technical and economic performance. [source] Captures of the olive fruit fly Bactrocera oleae on spheres of different coloursENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 2 2001Byron I. Katsoyannos Abstract Alighting and capture of wild olive fruit flies, Bactrocera oleae (Rossi) (Diptera, Tephritidae), on spheres of seven different colours was studied on Chios island, Greece. The 70-mm-diam plastic spheres, coated with adhesive, were suspended on olive trees. Yellow and orange spheres trapped the greatest number of males while red and black spheres trapped the greatest number of females. White and blue spheres were the least effective for both sexes. Peak captures occurred in the late afternoon and especially around sunset. Since mating takes place in the last hours of the photophase, the increased captures during that period may be related to the sexual behaviour of the fly. When red spheres were assessed against glass McPhail traps baited with 2% ammonium sulphate, which consist a standard tool for monitoring the olive fruit fly in Greece, there were no significant differences in male captures. However, spheres trapped almost three times as many females as McPhail traps. The possible mechanisms underlying colour discrimination, the motivation of alighting flies and the possible use of red spheres for monitoring and controlling B. oleae are discussed. [source] Partial regression method to fit a generalized additive modelENVIRONMETRICS, Issue 6 2007Shui He Abstract Generalized additive models (GAMs) have been used as a standard analytic tool in studies of air pollution and health during the last decade. The air pollution measure is usually assumed to be linearly related to the health indicator and the effects of other covariates are modeled through smooth functions. A major statistical concern is the appropriateness of fitting GAMs in the presence of concurvity. Generalized linear models (GLM) with natural cubic splines as smoothers (GLM,+,NS) have been shown to perform better than GAM with smoothing splines (GAM,+,S), in regard to the bias and variance estimates using standard model fitting methods. As nonparametric smoothers are attractive for their flexibility and easy implementation, search for alternative methods to fit GAM,+,S is warranted. In this article, we propose a method using partial residuals to fit GAM,+,S and call it the "partial regression" method. Simulation results indicate better performance of the proposed method compared to gam.exact function in S-plus, the standard tool in air pollution studies, in regard to bias and variance estimates. In addition, the proposed method is less sensitive to the degree of smoothing and accommodates asymmetric smoothers. Copyright © 2007 John Wiley & Sons, Ltd. [source] Power quality state estimationEUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 1 2010Neville R. Watson Abstract Due to the size and complexity of modern electrical power networks and the cost of monitoring and telecommunication equipment, it is unfeasible to fully monitor the system state. For this reason state estimation techniques are used. With strategically placed measurements, estimation techniques can determine the parameters at unmonitored locations. Fundamental frequency state estimation is now a standard tool in modern power systems. The emission and immunity levels of modern electrical equipment are different to that of the past, and this has resulted in power quality issues have become important. Knowledge of the source and location of the disturbances is desirable so that remedial action can be taken promptly. Recent contributions have extended the concept to: harmonic state estimation (HSE) and identification of harmonic sources, transient state estimation (TSE) and voltage sag state estimation (VSSE), which are all types of power quality state estimation (PQSE). This paper provides an overview of the state-of-the-art techniques currently available for PQSE in a large electrical power system. Copyright © 2009 John Wiley & Sons, Ltd. [source] Automated Evaluation of Kikuchi Patterns by Means of Radon and Fast Fourier Transformation, and Verification by an Artificial Neural Network,ADVANCED ENGINEERING MATERIALS, Issue 8 2003R.A. Schwarzer Automated crystal orientation measurement (ACOM) in the SEM by interpreting backscatter Kikuchi patterns (see Figure) has become a standard tool of quantitative texture analysis in materials science during the last decade. A Radon transformation of the diffraction pattern, in combination with a 1D fast Fourier transformation, enables the fast extraction of the positions of Kikuchi bands. The high-frequency coefficients of the 1D FFT are used to define pattern quality as a measure of lattice imperfection and residual stress of the real crystal structure. [source] The effectiveness of Cognitive,Behavioural Therapy with hopeful elements to prevent the development of depression in young people: a systematic reviewINTERNATIONAL JOURNAL OF EVIDENCE BASED HEALTHCARE, Issue 1 2009Anthony Venning B Hth Sci (Hons), B Soc Abstract Background, The onset of depression during adolescence can adversely impact future functioning. Cognitive,Behavioural Therapy (CBT) has been suggested to prevent depression in adolescence by providing an individual with the ability to interpret and the tools to deal with the impact of negative life events. Objective, Examine the best available evidence to determine the effectiveness of CBT to prevent the onset of depression in young people, and assess whether the incorporation of hopeful elements makes CBT more effective. Search strategy, A comprehensive three-step search strategy was developed to find both published and unpublished studies in English from 1987 to March 2007. Papers selected for retrieval were then assessed for methodological validity by two independent reviewers. Selection criteria, Papers that used a randomised controlled design and investigated the efficacy of CBT to prevent the onset of depression in young people between the age of 10 years and 16 years were included. Papers were included if the CBT involved between four and 15 sessions, a follow-up period of between 3 and 24 months and included typical strategies, such as the identification of negative and irrational beliefs, the establishment of links between thoughts, feelings and behaviours, and provided tools so participants could self-monitor these. Data analysis, Data were extracted using the standard tool from the Joanna Briggs Institute, pooled in a meta-analysis, and then grouped and analysed according to the amount of hopeful elements the CBT was judged to contain. Results and conclusion, Limited evidence was found to indicate that CBT, regardless of its content (i.e. with or without hopeful elements), is effective at preventing the onset of clinical levels of depression in young people on a sustained basis. Nonetheless, given the devastating impact that depression can have on young people's future functioning, further research is needed to develop effective interventions to equip young people with the cognitive skills to buffer its onset on a more sustained basis and to enable them to reach and sustain mental health. [source] Enabling a compact model to simulate the RF behavior of MOSFETs in SPICEINTERNATIONAL JOURNAL OF RF AND MICROWAVE COMPUTER-AIDED ENGINEERING, Issue 3 2005Reydezel Torres-Torres Abstract A detailed methodology for implementing a MOSFET model valid to perform RF simulations is described in this article. Since the SPICE-like simulation programs are used as a standard tool for integrated circuit (IC) design, the resulting model is oriented for its application under the SPICE environment. The core of the proposed model is the popular BSIM3v3, but in this model the RF effects are taken into account by means of extrinsic lumped elements. Good agreement between the simulated and measured small-signal S -parameter data is achieved for a 0.18-,m channel-length MOSFET, thus validating the proposed model. © 2005 Wiley Periodicals, Inc. Int J RF and Microwave CAE 15, 2005. [source] Using individual-based simulations to test the Levins metapopulation paradigmJOURNAL OF ANIMAL ECOLOGY, Issue 2 2002Matt J. Keeling Summary 1,Levins metapopulations have become a standard tool for modelling spatially heterogeneous populations. The acceptance of these models by ecologists may be attributed to their simple structure and their use of presence,absence data. 2,Using structured-metapopulations, which possess stochastic dynamics at the local subpopulation level, the extinction and subsequent recolonization rates can be calculated and compared to those of the classical Levins model. 3,Single-species metapopulations conform to the Levins ideal, validating the widespread use of this conceptual model. However, multispecies systems are shown to deviate in a consistent manner. This deviation, which is explained in terms of a correlation between patch occupancy and average population levels of the species, can be used to identify the signature of enemy,victim interactions. [source] Multivariate methods in pharmaceutical applicationsJOURNAL OF CHEMOMETRICS, Issue 3 2002Jon Gabrielsson Abstract This review covers material published within the field of pharmacy in the last five years. Articles concerning experimental design, optimization and applications of multivariate techniques have been published, from factorial designs to multivariate data analysis, and the combination of the two in multivariate design. The number of publications on this topic testifies to the good results obtained in the studies. Much of the published material highlights the usefulness of experimental design, with many articles dealing with optimization, where much effort is spent on getting useful results. Examples of multivariate data analysis are comparatively few, but these methods are gaining in use. The employment of multivariate techniques in different applications has been reviewed. The examples in this review represent just a few of the possible applications with different aims within pharmaceutical applications. A number of companies are using experimental design as a standard tool in preformulation and in combination with response surface modeling. The properties of e.g. a tablet can be optimized to fulfill a well-specified aim such as a specific release profile, hardness, disintegration time etc. However, none of the companies apply multivariate methods in all steps of the drug development process. As this is still very much a growing field, it is only a question of time before experimental design, optimization and multivariate data analysis are implemented throughout the entire formulation process, from performulation to multivariate process control. Copyright ©,2002 John Wiley & Sons, Ltd. [source] MELD and prediction of post,liver transplantation survivalLIVER TRANSPLANTATION, Issue 3 2006Shahid Habib The model for end-stage liver disease (MELD) was developed to predict short-term mortality in patients with cirrhosis. It has since become the standard tool to prioritize patients for liver transplantation. We assessed the value of pretransplant MELD in the prediction of posttransplant survival. We identified adult patients who underwent liver transplantation at our institution during 1991,2002. Among 2,009 recipients, 1,472 met the inclusion criteria. Based on pretransplant MELD scores, recipients were stratified as low risk (,15), medium risk (16,25), and high risk (>25). The primary endpoints were patient and graft survival. Mean posttransplant follow-up was 5.5 years. One-, 5- and 10-year patient survival was 83%, 72%, and 58%, respectively, and graft survival was 76%, 65%, and 53%, respectively. In univariable analysis, patient and donor age, patient sex, MELD score, disease etiology, and retransplantation were associated with posttransplantation patient and graft survival. In multivariable analysis adjusted for year of transplantation, patient age >65 years, donor age >50 years, male sex, and retransplantation and pretransplant MELD scores >25 were associated with poor patient and graft survival. The impact of MELD score >25 was maximal during the first year posttransplant. In conclusion, older patient and donor age, male sex of recipient, retransplantation, and high pretransplant MELD score are associated with poor posttransplant outcome. Pretransplant MELD scores correlate inversely with posttransplant survival. However, better prognostic models are needed that would provide an overall assessment of transplant benefit relative to the severity of hepatic dysfunction. Liver Transpl 12:440,447, 2006. © 2006 AASLD. [source] Quantifying spatial heterogeneity in dynamic contrast-enhanced MRI parameter mapsMAGNETIC RESONANCE IN MEDICINE, Issue 2 2009Chris J. Rose Abstract Dynamic contrast-enhanced MRI is becoming a standard tool for imaging-based trials of anti-vascular/angiogenic agents in cancer. So far, however, biomarkers derived from DCE-MRI parameter maps have largely neglected the fact that the maps have spatial structure and instead focussed on distributional summary statistics. Such statistics,e.g., biomarkers based on median values,neglect the spatial arrangement of parameters, which may carry important diagnostic and prognostic information. This article describes two types of heterogeneity biomarker that are sensitive to both parameter values and their spatial arrangement. Methods based on Rényi fractal dimensions and geometrical properties are developed, both of which attempt to describe the complexity of DCE-MRI parameter maps. Experiments using simulated data show that the proposed biomarkers are sensitive to changes that distribution-based summary statistics cannot detect and demonstrate that heterogeneity biomarkers could be applied in the drug trial setting. An experiment using 23 DCE-MRI parameter maps of gliomas,a class of tumour that is graded on the basis of heterogeneity,shows that the proposed heterogeneity biomarkers are able to differentiate between low- and high-grade tumours. Magn Reson Med, 2009. © 2009 Wiley-Liss, Inc. [source] The generalized spectral kurtosis estimatorMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY: LETTERS (ELECTRONIC), Issue 1 2010G. M. Nita ABSTRACT Due to its conceptual simplicity and its proven effectiveness in real-time detection and removal of radio frequency interference (RFI) from radio astronomy data, the spectral kurtosis (SK) estimator is likely to become a standard tool of a new generation of radio telescopes. However, the SK estimator in its original form must be developed from instantaneous power spectral density estimates, and hence cannot be employed as an RFI excision tool downstream of the data pipeline in existing instruments where any time averaging is performed. In this Letter, we develop a generalized estimator with wider applicability for both instantaneous and averaged spectral data, which extends its practical use to a much larger pool of radio instruments. [source] Measuring human energy expenditure: What have we learned from the flex-heart rate method?AMERICAN JOURNAL OF HUMAN BIOLOGY, Issue 4 2003William R. Leonard The measurement of daily energy expenditure is an important aspect of research on human health and nutrition. Over the last 30 years, G.B. Spurr has been a leader in developing and implementing methods for more effectively assessing energy expenditure and physical activity in traditional and modernizing populations. One of his most notable contributions has been the development of the "Flex Heart Rate" (flex-HR) method. Since its inception in the late 1980s, the flex-HR method has become a standard tool for measuring daily energy expenditure in free-living human populations. This article reviews the initial development and validation of the flex-HR technique, and examines recent refinements of the method and its application to research in biomedicine and human population biology. The review and analyses highlight how the flex-HR technique has improved on earlier methods of assessing energy expenditure and greatly advanced our understanding of variability in human energy requirements. Am. J. Hum. Biol. 15:479,489, 2003. © 2003 Wiley-Liss, Inc. [source] Assessment of demographic risk factors and management priorities: impacts on juveniles substantially affect population viability of a long-lived seabirdANIMAL CONSERVATION, Issue 2 2010M. E. Finkelstein Abstract Predicting population-level effects from changes in demographic rates of different life stages is critical to prioritize conservation efforts. Demographic modeling and sensitivity analysis in particular, has become a standard tool to evaluate how management actions influence species' survival. Demographic analyses have resulted in the robust generalization that, for long-lived species with delayed reproduction, population growth rates will be most sensitive to changes in survivorship of older-aged individuals. Although useful in guiding management, this simple maxim may limit options for conservation by causing managers to overlook actions that, although possibly not the most effective in terms of increasing a population's growth rate in an ideal world, can nonetheless more feasibly and rapidly slow a population's decline. We examine the population-level benefits of increasing chick survival in a long-lived seabird, the Laysan albatross Phoebastria immutabilis. Specifically, we use a simple deterministic modeling approach to evaluate the impact of chick mortality (from ingestion of lead-based paint) on the population growth rate (,) for Laysan albatross that breed on Sand Island, Midway Atoll (part of the Hawaiian Archipelago). We estimate that up to 7% of chicks on Sand Island fail to fledge as a result of lead poisoning, which will create a 16% reduction in the Laysan albatross population size (,190 000 less birds) at 50 years into the future. We demonstrate how straightforward management actions that increase juvenile survivorship (e.g. removal of lead-based paint) can help slow population declines while efforts are underway to reduce politically and logistically challenging threats to adult survivorship (e.g. mortality from international fisheries bycatch). Our work exemplifies a situation where overgeneralizations about demography can stifle useful conservation actions and highlights the need to consider the population-level benefits from multiple management strategies. [source] Hair diagnoses and signs: the use of dermatoscopyCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 1 2010M. P. Wallace Summary Background., Hair-shaft examination is diagnostically useful in a range of adult and paediatric conditions. Objective., To evaluate the usefulness of dermatoscopy in hair-shaft microscopy. Methods., Typical examples of selected conditions from an extensive collection of scalp hair were examined using a dermatoscope and a light microscope with paired cross-polarizing filters. Hair-shaft characteristics were photographed using a digital camera. Results., Dermatoscopy was helpful in detecting tapered hairs, weathering, monilethrix, pediculosis capitis, peripilar casts, ,exclamation-mark' hairs of alopecia areata, bubble hair and pili torti. It was less helpful in pili annulati and unhelpful in detecting ,tiger-tail' banding in trichothiodystrophy. Light microscopy provided greater detail in almost all cases; it was necessary for detection of cuticle changes and added significant information in detecting characteristic features of trichothiodystrophy, pili annulati, bubble hair and pili torti. Conclusions., Dermatoscopy is most revealing in conditions resulting in gross changes in shaft outline and colour, where reflected light is valuable. It is unhelpful for detection of features within the shaft or at higher levels of resolution. When added to its ability to aid evaluation of scalp surface characteristics, dermatoscopy provides an excellent first-line method of assessment in clinics. In vivo it may aid screening and selection of hairs of greatest diagnostic yield for further assessment. In some instances, it may obviate the need for obtaining hair specimens and have implications for public health screening. Where detailed or cortical hair-shaft features need assessment, transmitted light microscopy remains the standard tool. [source] Type 2 diabetes and cardiovascular disease in polycystic ovary syndrome: what are the risks and can they be reduced?DIABETIC MEDICINE, Issue 5 2010J. Tomlinson Diabet. Med. 27, 498,515 (2010) Abstract Polycystic ovary syndrome (PCOS) is a risk factor for Type 2 diabetes mellitus (T2DM) and cardiovascular disease (CVD), but these risks are poorly defined. This study aimed to evaluate the evidence for these risks and whether screening and risk reduction are feasible. Medline reviews and data quality analysis were used using standard tools. Results showed that (i) polycystic ovary syndrome is a risk factor forT2DM but the magnitude of risk is uncertain, (ii) fasting plasma glucose is an inadequate screening test forT2DM in this population and the oral glucose tolerance test is superior, (iii) the identification of women with PCOS for diabetes screening is constrained by current diagnostic criteria for PCOS; however, women with oligomenorrhoea and those with diagnosed PCOS and obesity or a family history of T2DM are at highest risk, (iv) risk factors for T2DM are improved by weight loss interventions and by metformin. However, no studies have determined whether T2DM incidence is reduced, (v) polycystic ovary syndrome is associated with cardiovascular disease (CVD) risk factors but data on CVD incidence are weak, (vi) risk factors for CVD are improved by the same interventions and statins and (vi) no studies have evaluated whether CVD incidence is reduced. While PCOS has important metabolic associations, and short-term interventions reduce risk factors for T2DM and CVD, data on prevalence and incidence of T2DM and particularly CVD are poor. There is a need for a clear definition of PCOS, for diabetes screening protocols and for long-term studies to determine whether risks can be reduced. [source] On the trail of the global green bean: methodological considerations in multi-site ethnographyGLOBAL NETWORKS, Issue 4 2001Susanne Freidberg The need to demystify and ,ground' globalization has spurred many calls for multi-site fieldwork. This article discusses how such fieldwork was used to examine the contemporary restructuring of fresh food commodity chains between Africa and Europe, at a time of increasing European concerns about food safety and quality. Drawing on convention theory and actor-network theory for conceptual guidance, qualitative fieldwork was conducted at sites of production, import and export in ,anglophone' (Zambia,London) and ,francophone' (Burkina Faso,Paris) commodity chains. The article also discusses the challenges posed by multi-site research, especially in realms where secrecy and deception are standard tools of the trade. [source] Assessing the economic impact of wind farms on tourism in Scotland: GIS, surveys and policy outcomesINTERNATIONAL JOURNAL OF TOURISM RESEARCH, Issue 3 2010Geoff Riddington Abstract The impact of wind farms on the environment and subsequently on tourism is the subject of much heated debate. The research was concerned with making a robust quantitative assessment of the economic impact, to help resolve the debate and inform government policy on planning for renewable energy. In addition to a broad description of the intercept surveys and the advanced local economic models used to ascertain impact, the research details two novel elements; a Geographic Information Systems (GIS) model for the analysis of the number of tourists and bed spaces exposed to wind farms and a large internet-based survey of the willingness to pay for landscape. The research found a very small but significant negative economic impact and, on the basis of the survey information, suggests ways of minimising this impact. Both GIS modelling and internet surveying were found to be extremely useful and, it is suggested, both should become standard tools for the tourism researcher. Copyright © 2009 John Wiley & Sons, Ltd. [source] Anatomics: the intersection of anatomy and bioinformaticsJOURNAL OF ANATOMY, Issue 1 2005Jonathan B. L. Bard Abstract Computational resources are now using the tissue names of the major model organisms so that tissue-associated data can be archived in and retrieved from databases on the basis of developing and adult anatomy. For this to be done, the set of tissues in that organism (its anatome) has to be organized in a way that is computer-comprehensible. Indeed, such formalization is a necessary part of what is becoming known as systems biology, in which explanations of high-level biological phenomena are not only sought in terms of lower-level events, but are articulated within a computational framework. Lists of tissue names alone, however, turn out to be inadequate for this formalization because tissue organization is essentially hierarchical and thus cannot easily be put into tables, the natural format of relational databases. The solution now adopted is to organize the anatomy of each organism as a hierarchy of tissue names and linking relationships (e.g. the tibia is PART OF the leg, the tibia IS-A bone) within what are known as ontologies. In these, a unique ID is assigned to each tissue and this can be used within, for example, gene-expression databases to link data to tissue organization, and also used to query other data sources (interoperability), while inferences about the anatomy can be made within the ontology on the basis of the relationships. There are now about 15 such anatomical ontologies, many of which are linked to organism databases; these ontologies are now publicly available at the Open Biological Ontologies website (http://obo.sourceforge.net) from where they can be freely downloaded and viewed using standard tools. This review considers how anatomy is formalized within ontologies, together with the problems that have had to be solved for this to be done. It is suggested that the appropriate term for the analysis, computer formulation and use of the anatome is anatomics. [source] MRI in fetal necropsyJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2006FRCR, Jocelyn S. Brookes MB Abstract The fetal autopsy involves a series of investigations of the corpse, most of which are noninvasive and acceptable to the majority of parents and their physicians. The value of the perinatal autopsy is manyfold and well established, and the results can provide a basis for parental and family counseling, inform future obstetric management, and provide audit for prenatal care. Many techniques originally developed for diagnosis, such as histology, biochemical tests, photography, x-rays, and cytogenetic karyotyping, have become standard tools in perinatal autopsies. However, there has been an inexorable decline in the autopsy consent rate over the last 30 years due to social and cultural factors, and perhaps ignorance of the benefits to be derived from the examination. Growing evidence suggests that postmortem fetal MRI can assist the pathologist at autopsy, and in many cases can obviate the need for dissection or at least minimize and focus it. For the majority of cases in which no consent for surgical autopsy is given, MRI together with other noninvasive postmortem tests can provide a great deal of the information that was previously available only from autopsy. J. Magn. Reson. Imaging 2006. © 2006 Wiley-Liss, Inc. [source] Averages of characteristic polynomials in random matrix theoryCOMMUNICATIONS ON PURE & APPLIED MATHEMATICS, Issue 2 2006A. Borodin We compute averages of products and ratios of characteristic polynomials associated with orthogonal, unitary, and symplectic ensembles of random matrix theory. The Pfaffian/determinantal formulae for these averages are obtained, and the bulk scaling asymptotic limits are found for ensembles with Gaussian weights. Classical results for the correlation functions of the random matrix ensembles and their bulk scaling limits are deduced from these formulae by a simple computation. We employ a discrete approximation method: the problem is solved for discrete analogues of random matrix ensembles originating from representation theory, and then a limit transition is performed. Exact Pfaffian/determinantal formulae for the discrete averages are proven using standard tools of linear algebra; no application of orthogonal or skew-orthogonal polynomials is needed. © 2005 Wiley Periodicals, Inc. [source] | ||||||||||||||||||||||