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Selected AbstractsToward a New Sexual Selection Paradigm: Polyandry, Conflict and Incompatibility (Invited Article)ETHOLOGY, Issue 12 2003Jeanne A. Zeh Darwin's recognition that male,male competition and female choice could favor the evolution of exaggerated male traits detrimental to survival set the stage for more than a century of theoretical and empirical work on sexual selection. While this Darwinian paradigm represents one of the most profound insights in biology, its preoccupation with sexual selection as a directional evolutionary force acting on males has diverted attention away from the selective processes acting on females. Our understanding of female reproduction has been further confounded by discreet female mating tactics that have perpetuated the illusion of the monogamous female and masked the potential for conflict between the sexes. With advances in molecular techniques leading to the discovery that polyandry is a pervasive mating strategy, recognition of these shortcomings has brought the study of sexual selection to its current state of flux. In this paper, we suggest that progress in two key areas is critical to formulation of a more inclusive, sexual selection paradigm that adequately incorporates selection from the female perspective. First, we need to develop a better understanding of male × female and maternal × paternal genome interactions and the role that polyandry plays in providing females with non-additive genetic benefits such as incompatibility avoidance. Consideration of these interaction effects influencing natural selection on females is important because they can complicate and even undermine directional sexual selection on males. Secondly, because antagonistic coevolution maintains a balance between opposing sides that obscures the conflict itself, many more experimental evolution studies and interventionist investigations (e.g. gene knockouts) are needed to tease apart male manipulative adaptations and female counter-adaptations. It seems evident that the divisiveness and controversy that has plagued sexual selection theory since Darwin first proposed the idea has often stalled progress in this important field of evolutionary biology. What is now needed is a more pluralistic and integrative approach that considers natural as well as sexual selection acting on females, incorporates multiple sexual selection mechanisms, and exploits advances in physiology and molecular biology to understand the mechanisms through which males and females achieve reproductive success. [source] Autoantibodies to coagulation factorsHAEMOPHILIA, Issue 102 2010J.-M. R. SAINT-REMY Summary., Tolerance to autoantigens such as coagulation factors is the result of censoring mechanisms occurring at the level of the thymus and bone marrow for autoreactive T and B cells, respectively. In addition, peripheral mechanisms, both intrinsic and extrinsic further control activation of autoreactive cells that have escaped central deletion. Emergence of autoimmunity can occur from disturbances of these control mechanisms by a number of events, many of which are incompletely understood. Insight into this clinically important field is expected from exploitation of recent animal models. [source] Quality Audit in Financial Investment ServicesINTERNATIONAL JOURNAL OF AUDITING, Issue 2 2000Stanislav Karapetrovic This paper discusses the following two questions: What is a ,Quality Audit'? Why and how does it apply to financial investment services? ,Quality' in this important field of service is understood as the perception of the investor about achieving satisfactory returns, under generally accepted risks, within a planned time. The service provider normally assures this quality with due care mostly in information gathering, communication and investment decision-making. Once this quality assurance is adequately formalized and documented, a ,quality audit' can be performed. The ISO 9000 international standards and guidelines describe a quality system that can be applied to provide meaningful quality assurance in investment services. Respective quality audits are described in the ISO 10011 Quality Audit Guideline. The development of quality assurance systems and quality audits for compliance and improved performance presents benefits to both the client and the investment service provider. [source] Computer-based morphometry of brainINTERNATIONAL JOURNAL OF IMAGING SYSTEMS AND TECHNOLOGY, Issue 2 2010Bang-Bon Koo Abstract Over the past decade, the importance of probing the anatomy of the brain has reemerged as an important field of neuroscience. In combination with functional imaging techniques, the rapid advancement of neuroimaging techniques,such as magnetic resonance imaging,and their growing applicability in studying brain morphometry has led to great advances in neuroscience research. Considering the requirements of the diverse technologies,from image processing to statistics,in performing morphometry of the brain, it is critical to have an overall understanding of this subject. The major objective of this review is to provide a practical introduction to this field. The review starts by covering basic concepts and techniques that are commonly used in morphometry of structural magnetic resonance imaging and then extends to further technical perspectives. © 2010 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 20, 117,125, 2010 [source] Performance measurement: a critical analysis of the literature with respect to total quality managementINTERNATIONAL JOURNAL OF MANAGEMENT REVIEWS, Issue 2 2000David Sinclair This paper represents a comprehensive review of the literature on performance measurement. The roadmap used for this analysis is from the evolution of performance measurement, to the way it is currently defined and how it is applied from a corporate-wide perspective. One useful contribution of this review is a special focus on performance measurement in a non-financial, non-traditional sense. This discussion was further amplified by referring to newly developed tools and techniques and by highlighting critical factors of success in the application of performance measurement. The key factors from this literature review reveal that, although interest in the area of measurement is growing significantly, this is not reflected by the tangible and credible experiences in the organizations concerned. There is a concurrent view amongst various writers that there are both hard and soft issues reflecting, for instance, the lack of strategic thinking and goal clarity, putting measurement systems in the driving seat and therefore trusting unreliable designs and not focusing on the true ethos of modern measurement towards continuous improvement and thereby not engaging employees and neglecting the culture change aspects. The paper concludes by highlighting the dearth in research in the important field of performance measurement and, in particular, the design and implementation of performance measurement systems that cover all the essential aspects through an integrated perspective. [source] Understanding participation in e-learning in organizations: a large-scale empirical study of employeesINTERNATIONAL JOURNAL OF TRAINING AND DEVELOPMENT, Issue 3 2010Thomas N. Garavan Much remains unknown in the increasingly important field of e-learning in organizations. Drawing on a large-scale survey of employees (N = 557) who had opportunities to participate in voluntary e-learning activities, the factors influencing participation in e-learning are explored in this empirical paper. It is hypothesized that key variables derived from the theories of planned behaviour and instructional design , general-person characteristics, motivation to learn, general and task-specific self-efficacy, situational barriers and enablers, and instructional design characteristics , will predict participation in e-learning. Using structural equation modelling, we find statistical support for the overall theoretical model proposed. We discuss the implications for practice. [source] Heterotachy and Functional Shift in Protein EvolutionIUBMB LIFE, Issue 4-5 2003Hervé Philippe Abstract Study of structure/function relationships constitutes an important field of research, especially for modification of protein function and drug design. However, the fact that rational design (i.e. the modification of amino acid sequences by means of directed mutagenesis, based on knowledge of the three-dimensional structure) appears to be much less efficient than irrational design (i.e. random mutagenesis followed by in vitro selection) clearly indicates that we understand little about the relationships between primary sequence, three-dimensional structure and function. The use of evolutionary approaches and concepts will bring insights to this difficult question. The increasing availability of multigene family sequences that has resulted from genome projects has inspired the creation of novel in silico evolutionary methods to predict details of protein function in duplicated (paralogous) proteins. The underlying principle of all such approaches is to compare the evolutionary properties of homologous sequence positions in paralogs. It has been proposed that the positions that show switches in substitution rate over time--i.e., 'heterotachous sites'--are good indicators of functional divergence. However, it appears that heterotachy is a much more general process, since most variable sites of homologous proteins with no evidence of functional shift are heterotachous. Similarly, it appears that switches in substitution rate are as frequent when paralogous sequences are compared as when orthologous sequences are compared. Heterotachy, instead of being indicative of functional shift, may more generally reflect a less specific process related to the many intra- and inter-molecular interactions compatible with a range of more or less equally viable protein conformations. These interactions will lead to different constraints on the nature of the primary sequences, consistently with theories suggesting the non-independence of substitutions in proteins. However, a specific type of amino acid variation might constitute a good indicator of functional divergence: substitutions occurring at positions that are generally slowly evolving. Such substitutions at constrained sites are indeed much more frequent soon after gene duplication. The identification and analysis of these sites by complementing structural information with evolutionary data may represent a promising direction to future studies dealing with the functional characterization of an ever increasing number of multi-gene families identified by complete genome analysis. IUBMB Life, 55: 257-265, 2003 [source] The aging male , diagnosis and therapy of late-onset hypogonadismJOURNAL DER DEUTSCHEN DERMATOLOGISCHEN GESELLSCHAFT, Issue 4 2008Gerhard Schreiber Summary Managing the clinical features of hormone insufficiency in aging men is an important field of activity for dermatologists and in particular for dermatologists specialized in andrology. Potential consequences of age-associated decrease in plasma testosterone levels include long-term changes in diverse organ systems including changes of bone architecture, body composition, muscular strength, cognitive functions, and mood as well as negative effects on skin and hair. Indications and contraindications for a hormone replacement therapy as well as therapy monitoring are well-defined. Replacement of testosterone in the case of late-onset hypogonadism is not a standardized therapy. Previous studies suggest that testosterone replacement therapy has positive clinical effects. Dermatologic effects of testosterone replacement therapy have not yet been investigated. Further research is required to identify potential benefits and risks of hormone replacement therapy in aging men. [source] Future eating and country keeping: what role has environmental history in the management of biodiversity?JOURNAL OF BIOGEOGRAPHY, Issue 5 2001D.M.J.S. Bowman In order to understand and moderate the effects of the accelerating rate of global environmental change land managers and ecologists must not only think beyond their local environment but also put their problems into a historical context. It is intuitively obvious that historians should be natural allies of ecologists and land managers as they struggle to maintain biodiversity and landscape health. Indeed, ,environmental history' is an emerging field where the previously disparate intellectual traditions of ecology and history intersect to create a new and fundamentally interdisciplinary field of inquiry. Environmental history is rapidly becoming an important field displacing many older environmentally focused academic disciplines as well as capturing the public imagination. By drawing on Australian experience I explore the role of ,environmental history' in managing biodiversity. First I consider some of the similarities and differences of the ecological and historical approaches to the history of the environment. Then I review two central questions in Australian environment history: landscape-scale changes in woody vegetation cover since European settlement and the extinction of the marsupials in both historical and pre-historical time. These case studies demonstrate that environmental historians can reach conflicting interpretations despite using essentially the same data. The popular success of some environmental histories hinges on the fact that they narrate a compelling story concerning human relationships and human value judgements about landscape change. Ecologists must learn to harness the power of environmental history narratives to bolster land management practices designed to conserve biological heritage. They can do this by using various currently popular environmental histories as a point of departure for future research, for instance by testing the veracity of competing interpretations of landscape-scale change in woody vegetation cover. They also need to learn how to write parables that communicate their research findings to land managers and the general public. However, no matter how sociologically or psychologically satisfying a particular environmental historical narrative might be, it must be willing to be superseded with new stories that incorporate the latest research discoveries and that reflects changing social values of nature. It is contrary to a rational and publicly acceptable approach to land management to read a particular story as revealing the absolute truth. [source] Label free optical sensor for Avidin based on single gold nanoparticles functionalized with aptamersJOURNAL OF BIOPHOTONICS, Issue 4 2009Frank Jeyson Hernandez Abstract Optical spectroscopy of a single gold nanoparticle, functionalized with an aptamer, is used to sense the specific binding of avidin. Herewith, the field of single noble metal nanoparticle biosensors is extended to the important field of aptamer based assays. The sensitivity of this initial, but not yet optimized apta-nano-sensor is in the range of 20 nM. Due to its nanoscopic size, this single nanoparticle based apta-sensor may be used in nanoscopic volumes such as in array type assays or even inside cells. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] German welfare organizations and the process of European integrationNONPROFIT MANAGEMENT & LEADERSHIP, Issue 3 2003Chris Lange The process of European integration affects an increasing number of areas of life. The influence of the European single market on the social sector, including organizations providing human services, can no longer be denied. This article looks at the activities of the European Commission toward these organizations and argues that European regulations are relevant to the German system of social service delivery due to the introduction of market-like features in the national context. Within this context, German welfare organizations have discovered an important field of interest representation and lobbying. [source] When is a maternal effect adaptive?OIKOS, Issue 12 2007Dustin J. Marshall Maternal effects have become an important field of study in evolutionary ecology and there is an ongoing debate regarding their adaptive significance. Some maternal effects can act to increase offspring fitness and are called ,adaptive maternal effects'. However, other maternal effects decrease offspring fitness and there is confusion regarding whether certain maternal effects are indeed adaptive or merely physiological inevitabilities. Here we suggest that the focus on the consequences of maternal effects for offspring fitness only and the use of ,snapshot' estimates of fitness have misdirected our effort to understand the evolution of maternal effects. We suggest that selection typically acts on maternal effects to maximise maternal rather than (or in addition to) offspring fitness. We highlight the importance of considering how maternal effects influence maternal fitness across a mother's lifetime and describe four broad types of maternal effects using an outcome-based approach. Overall, we suggest that many maternal effects will have an adaptive basis for mothers, regardless of whether these effects increase or decrease survival or reproductive success of individual offspring. [source] Preface: phys. stat. sol. (c) 1/9PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 9 2004Andrew Leitch The Conference on Photo-responsive Materials took place at the Kariega Game Reserve in the Eastern Cape, South Africa from 25,29 February 2004. More than 60 delegates from 12 different countries participated in the four-day event. The purpose of the conference was to bring together scientists working on various aspects of photo-responsive materials, so as to stimulate this important field of solid state physics in Southern Africa. As may be seen from the list of papers appearing in these proceedings, there was much interest in copper indium diselenide as a thin film material for photovoltaic applications. Also worth mentioning were the valuable contributions on ZnO, GaN and other materials that are currently attracting attention worldwide. The conference program allowed sufficient time for interaction and exchanging of views. Being in a game reserve in the heart of the beautiful Eastern Cape, delegates were also taken on game drives and had the opportunity of taking a river cruise up the Kariega River to view the majestic fish eagle. The members of the academic program committee were: Vivian Alberts (Rand Afrikaans University), Danie Auret (University of Pretoria), Darrell Comins (University of the Witwatersrand), and Reinhardt Botha and Andrew Leitch (University of Port Elizabeth). All papers appearing in these proceedings underwent a strict reviewing process separate from the conference. We express our appreciation to the referees for their diligence in this important task. The conference was organized by the Department of Physics at the University of Port Elizabeth, under the auspices of the Condensed Matter Physics and Materials Science (CMPMS) subgroup of the South African Institute of Physics. It was sponsored by EMF Limited (UK), Sensors Unlimited Inc. (USA), and Carl Zeiss (Pty) Ltd. Special thanks must go to Dr Eunete van Wyk for her professional assistance in the preparation of these proceedings. [source] Mass spectrometry in clinical proteomics , from the present to the futurePROTEOMICS - CLINICAL APPLICATIONS, Issue 1 2009Magnus Palmblad Abstract MS is an important analytical tool in clinical proteomics, primarily in the disease-specific discovery, identification and characterisation of proteomic biomarkers and patterns. MS-based proteomics is increasingly used in clinical validation and diagnostic method development. The latter departs from the typical application of MS-based proteomics by exchanging some of the high performance of analysis for the throughput, robustness and simplicity required for clinical diagnostics. Although conventional MS-based proteomics has become an important field in clinical applications, some of the most recent MS technologies have not yet been extensively applied in clinical proteomics. In this review, we will describe the current state of MS in clinical proteomics and look to the future of this field. [source] A perspective of metabolic engineering strategies: moving up the systems hierarchyBIOTECHNOLOGY & BIOENGINEERING, Issue 7 2003Thomas Bulter Abstract Metabolic engineering has been established as an important field in biotechnology. It involves the analysis, design, and alteration of the stoichiometric network using sophisticated mathematical and molecular biology techniques. It allows for improvement of pathway kinetics by removing flux bottlenecks, balancing precursors, and recycling cofactors used to increase product formation. The next step in the systems hierarchy is the constructive manipulation of regulatory networks. As our understanding of regulation continues to expand rapidly, engineering of intracellular regulation will become an integral aspect of metabolic engineering. © 2003 Wiley Periodicals, Inc. [source] ,-Herpesviruses and cellular signaling in AIDS-associated malignanciesCANCER SCIENCE, Issue 9 2007Kohji Noguchi ,-Herpesviruses, Epstein,Barr virus (EBV/HHV-4) and Kaposi's sarcoma-associated herpesvirus (KSHV/HHV-8), are involved in human carcinogenesis, particularly in immunocompromised patients. Virus-associated malignancies are becoming of significant concern for the mortality of long-lived immunocompromised patients, and therefore, research of advanced strategies for AIDS-related malignancies is an important field in cancer chemotherapy. Detailed understanding of the EBV and KSHV lifecycle and related cancers at the molecular level is required for novel strategies of molecular-targeted cancer chemotherapy. The present review gives a simple outline of the functional interactions between KSHV- and EBV-viral gene products and host cell deregulated signaling pathways as possible targets of chemotherapy against AIDS-related malignancies. (Cancer Sci 2007; 98: 1288,1296) [source] Nichtlineare stochastische Optimierung unter UnsicherheitenCHEMIE-INGENIEUR-TECHNIK (CIT), Issue 7 2003H. Arellano-Garcia Dipl.-Ing. Abstract Das Treffen von Entscheidungen unter Berücksichtigung von Unsicherheiten wird in zahlreichen Fachrichtungen und Anwendungsgebieten als grundlegend wichtig erachtet. In dynamischen chemischen Prozessen existieren insbesondere Parameter, die üblicherweise unsicher sind und große Auswirkungen auf die Auslegung von Anlagen, die Betriebsdurchführung sowie auf die wirtschaftliche Analyse haben. Daher ist die Einbeziehung der Stochastik der unsicheren Variablen in die Formulierung eines Optimierungsproblems in Hinblick auf ein optimales Prozessdesign sowie auf eine robuste Prozessführung notwendig. Infolgedessen ist die effiziente Optimierung unter Wahrscheinlichkeitsrestriktionen zu einem wichtigen Forschungsgebiet in der Prozesssystemtechnik geworden. Ein neuer Lösungsansatz für die stochastische Optimierung dynamischer Systeme wird am Beispiel eines diskontinuierlichen Prozesses mit einem rigorosen Modell vorgestellt und angewandt. Nonlinear Stochastic Optimization under Uncertainty Robust decision making under uncertainty is considered to be of fundamental importance in numerous disciplines and application areas. In dynamic chemical processes in particular there are parameters which are usually uncertain, but may have a large impact on equipment decisions, plant operability, and economic analysis. Thus the consideration of the stochastic property of the uncertainties in the optimization approach is necessary for robust process design and operation. As a part of it, efficient chance constrained programming has become an important field of research in process systems engineering. A new approach is presented and applied for stochastic optimization problems of batch distillation with a detailed dynamic process model. [source] Colloidal-Crystal-Assisted Patterning of Crystalline MaterialsADVANCED MATERIALS, Issue 13 2010Cheng Li Abstract Colloidal crystals have shown great potential as versatile templates for the fabrication of patterned micro- and nanostructures with complex architectures and novel properties. The patterning of functional crystalline materials in two and three dimensions is essential to the realization of their applications in many technologically important fields. This article highlights some recent progress in the fabrication of 2D and 3D patterned crystalline materials with the assistance of colloidal crystals. By combining a bioinspired synthetic strategy based on a transient amorphous phase with a colloidal-crystal templating method, unique 3D ordered macroporous (3DOM) calcite single crystals can be created. Moreover, patterned arrays of regular ZnO nanopillars with controlled size, shape, and orientation can be fabricated via a facile wet chemical approach by using masks derived from monolayer colloidal crystals (MCC). [source] Chemischer Apparatebau im Aufbruch?CHEMIE-INGENIEUR-TECHNIK (CIT), Issue 5 2003E. Weiß Prof. Dr.-Ing. Abstract Die ACHEMA stellt eine eindrucksvolle Leistungsschau des Apparatebaus dar, die im engen Zusammenhang mit den epochalen Entwicklungen der Verfahrens- und Prozesstechnik steht. Dies ist ein günstiger Zeitpunkt, um über die Entwicklungschancen nachzudenken. Der Großanlagenbau hat in den letzten Jahrzehnten eine beträchtliche Korrektur erfahren, was sich besonders auf den deutschen Apparatebau ausgewirkt hat. Wirtschaftliche Zwänge lieferten einen zusätzlichen Anstoß für einen beachtlichen Schrumpfungsprozess. Der Apparatebau muss sich in der Zukunft auf zwei Standbeine konzentrieren: Hochqualifizierte Standardapparate und neuartige Produkte, die im engen Zusammenwirken mit der Verfahrenstechnik entwickelt werden müssen, um für neue Technologien und Prozessstrategien die erforderliche Hardware auf den Markt zu bringen. Der Beitrag nennt Gebiete, in denen sich der allgemeine technische Fortschritt manifestiert, aber auch aus der apparatetechnischen Sicht werden Anstöße vermittelt, wie ein gehobenes Qualitätsniveau der Produkte erreicht werden kann. Hierbei handelt es sich durchaus um Eigenschaften, die sich letztlich im wirtschaftlichen Ergebnis niederschlagen. Chemical Apparatus Engineering at a Turning Point? The ACHEMA conference is the leading international exhibition on chemical-apparatus engineering, closely connected with the epochal developments of chemical and process engineering. At the moment it is most timely to think about new opportunities of development. Large-scale plant engineering and general plant construction has experienced considerable improvement over the past decades, and the effects of these changes are particularly perceptible in the economic sector of German apparatus engineering. Economic pressures have given an additional impetus to a considerable shrinking process. Chemical apparatus engineering will have to focus on two main pillars in the near future: highly qualified standard and innovative products. Especially the latter must be developed in close interaction with chemical engineering in order to put the hardware required for new technologies and process strategies on the market. This article names the important fields of current general technical progress, showing that the main thrust is directed toward an elevated level of product quality that can be achieved through apparatus engineering. Such superior product properties are one important means to achieve higher profitability. [source] Ferrocenyl-Ended Thieno,Vinylene Oligomers: Donor,Acceptor Polarization and Mixed-Valence Properties with Emphasis on the Raman Mapping of Localized-to-Delocalized TransitionsCHEMISTRY - A EUROPEAN JOURNAL, Issue 11 2009Juan Casado Dr. Abstract What's your role? New oligothiophene,vinylene compounds have been synthesized to study the role of the conjugated chain in two different cases (see scheme; MV=mixed valence). The electronic and molecular structures were analyzed by means of electronic, X-ray photoelectron, and Raman spectroscopy, together with thermo spectroscopy, electrochemistry, and DFT calculations. New oligothiophene,vinylene compounds have been synthesized in order to study the role of the conjugated chain in two different cases: 1),when push,pull action operates between an electron-donor and an electron-acceptor group at the ends of the thiophene,vinylene conjugated chain, and 2),when mixed-valence action is induced by single oxidation of the same chain functionalized at both terminal positions with ferrocene groups leading to competition between the donor groups. The electronic and molecular structures are analyzed by means of electronic, X-ray photoelectron and Raman spectroscopies, together with thermospectroscopy, electrochemistry and density functional theory calculations. The cyclic voltammetry processes have been followed by spectrochemistry. It is shown that the radical cation of the diferrocenyl derivative is a class,III mixed-valence system (i.e., fully delocalized) according to its Raman spectrum. Moreover, by Raman thermo-spectroscopy the thermal transition of this radical cation from a delocalized (class,III, room temperature) to a localized (class,II, ,160,°C) state is scanned. In all cases the Raman study is paralleled by an electronic absorption spectroscopic analysis. Structure,property relationships are proposed for molecules of two important fields of very active research as that of the non-linear optics (i.e., organic optoelectronic) and that of the mixed-valence systems (i.e., charge-transfer processes). [source] Preparation of Nearly Monodisperse Nanoscale Inorganic PigmentsCHEMISTRY - AN ASIAN JOURNAL, Issue 1-2 2006Dingsheng Wang Abstract Many different important commercial pigments have been synthesized based on the liquid,solid,solution (LSS) phase-transfer and separation process. Transmission electron microscopy (TEM) measurement results show that they are very small in size and have a narrow size distribution. Visible absorption spectra were taken to examine the very pure and brilliant colors of the pigments. They can be well-dispersed in cyclohexane and remain non-agglomerated, even over several months. These nearly monodisperse nanoscale inorganic pigments may have wide applications in many important fields and could bring about new developments in the pigment industry. [source] | ||||||||||||||||||||||