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Selected AbstractsCorporate Governance and Competitive Advantage in Family-Controlled FirmsENTREPRENEURSHIP THEORY AND PRACTICE, Issue 3 2005Michael Carney Recent attempts to identify the basis of family-controlled firms' competitive advantage have drawn upon the resource-based view of the firm. This article supplements these efforts and advances the argument that family-controlled firms' competitive advantage arises from their system of corporate governance. Systems of corporate governance embody incentives, authority patterns, and norms of legitimation that generate particular organizational propensities to create competitive advantages and disadvantages. For comparative purposes, the characteristics of managerial, alliance, and family governance are reviewed. The impact of a family's control rights over a firm's assets generates three dominant propensities (parsimony, personalism, and particularism). These propensities give advantages in scarce environments, facilitate the creation and utilization of social capital, and engender opportunistic investment processes. The experience of family-controlled firms in emerging markets is drawn upon to illustrate the argument. [source] THE CLASSROOM AS THE FIELD FOR STUDYING GEOGRAPHICAL EDUCATIONGEOGRAPHICAL REVIEW, Issue 4 2001L. JEAN PALMER-MOLONEY ABSTRACT. Recent attempts by U.S. politicians to reform the nation'sschools have shifted the goal of education to school accountability as assessed in standardized testing. Such an emphasis undermines geographical education in schools because of geography'ssuperficial representation in tests and in the social studies curriculum. Fieldwork done in the classroom can point to means of circumventing this dilemma. Collaborative fieldwork between college faculty members and public-school teachers has the potential for adding geography to the social studies curriculum in a substantive way. Work conducted jointly by Hartwick College and the Oneonta (New York) Middle School exemplifies such a partnership. [source] Use and misuse of the IUCN Red List Criteria in projecting climate change impacts on biodiversityGLOBAL CHANGE BIOLOGY, Issue 11 2006H. RESIT AKÇAKAYA Abstract Recent attempts at projecting climate change impacts on biodiversity have used the IUCN Red List Criteria to obtain estimates of extinction rates based on projected range shifts. In these studies, the Criteria are often misapplied, potentially introducing substantial bias and uncertainty. These misapplications include arbitrary changes to temporal and spatial scales; confusion of the spatial variables; and assume a linear relationship between abundance and range area. Using the IUCN Red List Criteria to identify which species are threatened by climate change presents special problems and uncertainties, especially for shorter-lived species. Responses of most species to future climate change are not understood well enough to estimate extinction risks based solely on climate change scenarios and projections of shifts and/or reductions in range areas. One way to further such understanding would be to analyze the interactions among habitat shifts, landscape structure and demography for a number of species, using a combination of models. Evaluating the patterns in the results might allow the development of guidelines for assigning species to threat categories, based on a combination of life history parameters, characteristics of the landscapes in which they live, and projected range changes. [source] The Marriage of Marx and Darwin?HISTORY AND THEORY, Issue 1 2002Doyne Dawson Recent attempts to develop scientific research strategies for cultural evolution have mostly drawn upon evolutionary biology, but within anthropology there is also an influential tradition of non-biological evolutionary thought whose basic principle is adaptation to the environment. This article is mainly concerned with the "cultural materialist" school of Marvin Harris, but also treats the recent attempt of Jared Diamond to create a more radical model of evolutionary ecology. I argue that the ecological tradition does not represent a real alternative to neo-Darwinism and is in fact a pseudo-Darwinist theory. I also suggest that the bias in favor of materialistic explanation in cultural evolution may not be justified. [source] Conceptualization of mild cognitive impairment: a reviewINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 4 2004Heather S. Davis Abstract Background Several factors have prompted renewed interest in the concept of declines in cognitive function that occur in association with aging, in particular the area between normal cognition and dementia. We review the changing conceptualization of what has come to be known as mild cognitive impairment (MCI) in an effort to identify recent developments and highlight areas of controversy. Methods Standard MEDLINE search for relevant English-language publications on mild cognitive impairment and its associated terms, supplemented by hand searches of pertinent reference lists. Results Many conditions cause cognitive impairment which does not meet current criteria for dementia. Within this heterogenous group, termed ,Cognitive Impairment, No Dementia' (CIND), there are disorders associated with an increased risk of progression to dementia. Still, the conceptualization of these latter disorders remains in flux, with variability around assumptions about aging, the relationship between impairment and disease, and how concomitant functional impairment is classified. Amongst patients with MCI, especially its amnestic form, many will progress to Alzheimer's disease (AD). In contrast with clinic-based studies, where progression is more uniform, population-based studies suggest that the MCI classification is unstable in that context. In addition to Amnestic Mild Cognitive Impairment (AMCI), other syndromes exist and can progress to dementia. For example, an identifiable group with vascular cognitive impairment without dementia shows a higher risk of progression to vascular dementia, Alzheimer's disease and mixed dementia. Conclusions Recent attempts to profile patients at an increased risk of dementia suggest that this can be done in skilled hands, especially in people whose symptoms prompt them to seek medical attention. Whether these people actually have early AD remains to be determined. The more narrowly defined MCI profiles need to be understood in a population context of CIND. Copyright © 2004 John Wiley & Sons, Ltd. [source] Using participatory methods and geographic information systems (GIS) to prepare for an hiv community-based trial in Vulindlela, South Africa (Project Accept,HPTN 043),,JOURNAL OF COMMUNITY PSYCHOLOGY, Issue 1 2009Admire Chirowodza Recent attempts to integrate geographic information systems (GIS) and participatory techniques, have given rise to terminologies such as participatory GIS and community-integrated GIS. Although GIS was initially developed for physical geographic application, it can be used for the management and analysis of health and health care data. Geographic information systems, combined with participatory methodology, have facilitated the analysis of access to health facilities and disease risk in different populations. Little has been published about the usefulness of combining participatory methodologies and GIS technology in an effort to understand and inform community-based intervention studies, especially in the context of HIV. This article attempts to address this perceived gap in the literature. The authors describe the application of participatory research methods with GIS in the formative phase of a multisite community-based social mobilization trial, using voluntary counseling and testing and post-test support as the intervention. © 2008 Wiley Periodicals, Inc. [source] Prisoners' Adjustment, Correctional Officers, and Context: The Foreground and Background of Punishment in Late ModernityLAW & SOCIETY REVIEW, Issue 2 2008Mike Vuolo Past research indicates that front-line criminal justice workers are the critical players in determining whether innovations in penal policy are realized. Recent attempts to understand the diversity in the application of the penal harm movement have, however, sidestepped the primary audience of these policies, the population of convicted offenders. This article uses data from two prisons to examine the effects of correctional officers on women prisoners' adjustment to prison life. Using regression models and interview data, we find that correctional officer behavior has a profound impact on women's ability to adjust to prison, and this effect is largely independent of the prisoners' characteristics and the institutions in which they are housed. On a theoretical level, the findings speak to recent calls to examine the background and foreground of penal culture. On a practical level, they highlight the need to understand the environments from which women are emerging, not just the communities into which they are released. [source] Privacy protection, health care and quality controlQUALITY ASSURANCE JOURNAL, Issue 3 2002Rudolf Bruppacher Abstract In the past three decades, patient rights on the one hand, and health care and research activities in health services on the other hand, have experienced unprecedented development. Requirements of privacy protection, particularly the restrictions on ,secondary analysis' of health data, have become a problem in an increasingly complex health care environment and have become a hindrance to research. Legal regulations have developed differently in different countries. Recent attempts, such as the European Community directive on privacy protection promise effective harmonization, at least for developed countries. However, many questions regarding their interpretation remain and they are discussed in this article. Copyright © 2002 John Wiley & Sons, Ltd. [source] Nutritional Response to the 1998 Bangladesh Flood Disaster: Sphere Minimum Standards in Disaster ResponseDISASTERS, Issue 3 2002Max R. O'Donnell In this study we use a cross,sectional survey to evaluate the nutritional response to the 1998 Bangladesh Flood Disaster by 15 relief agencies using standards developed by the Sphere Project. The Sphere Project is a recent attempt by agencies around the world to establish universal minimum standards for the purpose of ensuring quality and accountability in disaster response. The main outcomes measured were resources allocated to disaster relief, types of relief activities and percentage of agencies meeting selected Sphere food aid and nutrition indicators. Although the process of nutritional response was measured, specific nutritional and health outcomes were not assessed. This review found that self,reported disaster and nutritional resources varied widely between implementing agencies, ranging from US$58,947 to $15,908,712. The percentage of resources these agencies allocated to food aid and nutritional response also varied, ranging from approximately 6 to 99 per cent of total resources. Agencies met between 8 and 83 per cent of the specific Sphere indicators which were assessed. Areas in which performance was poor included preliminary nutritional analysis; beneficiary participation and feedback; disaster preparedness during non,emergency times; monitoring of local markets and impact assessment. Agencies were generally successful in areas of core humanitarian response, such as targeting the vulnerable (83 per cent) and monitoring and evaluating the process of disaster response (75 per cent). The results here identify both strengths and gaps in the quality of humanitarian response in developing nations such as Bangladesh. However, they also raise the question of implementing a rights,based approach to disaster response in nations without a commitment to meeting positive human rights in non,disaster times. [source] Landscape issues in plant ecologyECOGRAPHY, Issue 2 2002Sylvie De Blois In the last decade, we have seen the emergence and consolidation of a conceptual framework that recognizes the landscape as an ecological unit of interest. Plant ecologists have long emphasized landscape-scale issues, but there has been no recent attempt to define how landscape concepts are now integrated in vegetation studies. To help define common research paradigms in both landscape and plant ecology, we discuss issues related to three main landscape concepts in vegetation researches, reviewing theoretical influences and emphasizing recent developments. We first focus on environmental relationships, documenting how vegetation patterns emerge from the influence of local abiotic conditions. The landscape is the physical environment. Disturbances are then considered, with a particular attention to human-driven processes that often overrule natural dynamics. The landscape is a dynamic space. As environmental and historical processes generate heterogeneous patterns, we finally move on to stress current evidence relating spatial structure and vegetation dynamics. This relates to the concept of a landscape as a patch-corridor-matrix mosaic. Future challenges involve: 1) the capacity to evaluate the relative importance of multiple controlling processes at broad spatial scale; 2) better assessment of the real importance of the spatial configuration of landscape elements for plant species and finally; 3) the integration of natural and cultural processes and the recognition of their interdependence in relation to vegetation management issues in human landscapes. [source] Unplanned attempts to quit smoking: a qualitative explorationADDICTION, Issue 7 2010Rachael L. Murray ABSTRACT Aims To gain a greater understanding of the process of unplanned attempts to quit smoking and the use of support in such attempts. Design Qualitative study using semi-structured interviews with 20 smokers and ex-smokers. Setting Twenty-four general practices in Nottinghamshire, UK. Participants Smokers and ex-smokers who reported that their most recent attempt to quit smoking was unplanned. Measurements Descriptions of the unplanned quit attempts and reported use of support within these. Findings Smokers who report making ,unplanned' quit attempts exhibit substantial variation in what they mean by this; many quit attempts reported as ,unplanned' were actually delayed and involved some planning and use of cessation support. Conclusions Reported ,unplanned' quit attempts often involve elements of planning and delay for quitters to access to cessation support. It is important, therefore, that smoking cessation services offer flexible and adaptable support which can be used readily by potential quitters. [source] The Marriage of Marx and Darwin?HISTORY AND THEORY, Issue 1 2002Doyne Dawson Recent attempts to develop scientific research strategies for cultural evolution have mostly drawn upon evolutionary biology, but within anthropology there is also an influential tradition of non-biological evolutionary thought whose basic principle is adaptation to the environment. This article is mainly concerned with the "cultural materialist" school of Marvin Harris, but also treats the recent attempt of Jared Diamond to create a more radical model of evolutionary ecology. I argue that the ecological tradition does not represent a real alternative to neo-Darwinism and is in fact a pseudo-Darwinist theory. I also suggest that the bias in favor of materialistic explanation in cultural evolution may not be justified. [source] Dementia, cognitive impairment and mortality in persons aged 65 and over living in the community: a systematic review of the literatureINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 8 2001Michael E. Dewey Abstract Background No recent attempt has been made to synthesise information on mortality and dementia despite the theoretical and practical interest in the topic. Our objective was to estimate the influence on mortality of cognitive impairment and dementia. Methods Data sources were Medline, Embase, personal files and colleagues' records. Studies were considered if they included a majority of persons aged 65 and over at baseline either drawn from a total community sample or drawn from a random sample from the community. Samples from health care facilities were excluded. The search located 68 community studies. Effect sizes were extracted from the studies and if they were not included in the published studies, effect sizes were calculated where possible: this was possible for 23 studies of cognitive impairment and 32 of dementia. No attempt was made to contact authors for missing data. Results For the studies of cognitive impairment Fisher's method (a vote counting method), gave a p -value (from eight studies) of 0.00001. For studies of dementia, age-adjusted confidence intervals (CI) were pooled (odds ratio (OR) 2.63 with 95% CI 2.17 to 3.21 from six studies). Conclusions Levels of cognitive impairment commonly found in community studies give rise to an increased risk of mortality, and this appears to be true even for quite mild levels of impairment. The analysis confirms the increased risk of mortality for dementia, but reveals a dearth of information on the causes of the excess mortality and on possible effect modification by age, dementia subtype or other variables. Copyright © 2001 John Wiley & Sons, Ltd. [source] Depression, depressive symptoms and mortality in persons aged 65 and over living in the community: a systematic review of the literatureINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 6 2001Pedro Saz Abstract Background No recent attempt has been made to synthesize information on mortality and depression despite the theoretical and practical interest in the topic. Our objective was to estimate in the older population the influence on mortality of depression and depressive symptoms. Methods Data sources were: Medline, Embase, personal files and colleagues' records. Studies were considered if they included a majority of persons aged ,,65 years at baseline either drawn from a total community sample or drawn from a random sample from the community. Samples from healthcare facilities were excluded. Effect sizes were extracted from the papers; if they were not included in the published papers, effect sizes were calculated if possible. No attempt was made to contact authors for missing data. Results We found 21 reports on 23 cohorts using depression diagnosis. For 15 of these, odds ratios were pooled using the Greenland method based on confidence intervals (CIs), giving an estimated odds ratio for mortality with depression of 1.73 (95% CI 1.53 to 1.95). A fixed effects meta-regression of these studies suggested that longer follow-up predicted smaller effect sizes (log odds ratios ,0.096 per year (95% CI ,0.179 to ,0.014)). There is a weak suggestion of a reduced effect of depression on mortality for women. We were unable to pool effect sizes from the 17 studies using symptom totals and scales, or from eight studies of specific symptoms. Conclusions The studies show that diagnosed depression in community-resident older people is associated with increased mortality. The picture for sex differences is still unclear. Copyright © 2001 John Wiley & Sons, Ltd. [source] There is No Puzzle about ChangeDIALECTICA, Issue 1 2009Pablo Rychter This paper argues against the common practice of presenting perdurantism, endurantism, and other views about persistence and time as solutions to an alleged puzzle about change. Various recent attempts to generate a puzzle about change are examined and found unsuccessful. This does not mean, however, that the relevant views about persistence and time are not well motivated, but rather that their interest and purpose is independent of their suitability for solving the alleged puzzle. [source] Knowledge and Varieties of Epistemic LuckDIALECTICA, Issue 4 2001Hamid Vahi It is generally thought that knowledge is incompatible with epistemic luck as the post-Gettier literature makes it abundantly clear. Examples are produced where although a belief is true and justified, it nevertheless falls short of being an instance of knowledge because of the intrusion of luck. Knowledge is regarded as being distinct from lucky guesses. It is, nevertheless, acknowledged by a number of epistemologists that some kind of luck is in fact an inevitable component of the process of knowledge acquisition. In this paper I wish to delineate varieties of epistemic luck in the light of the Gettier literature, and specify the kind that should be tolerated in the process of acquiring knowledge. To do this, it would be best to start by examining some of the recent attempts at analyzing the concept of luck and its bearing on the concept of knowledge. [source] Evolution of invertebrate nervous systems: the Chaetognatha as a case studyACTA ZOOLOGICA, Issue 1 2010Steffen Harzsch Abstract Harzsch, S. and Wanninger, A. 2010. Evolution of invertebrate nervous systems: the Chaetognatha as a case study. ,Acta Zoologica (Stockholm) 91: 35,43 Although recent molecular studies indicate that Chaetognatha may be one of the earliest Bilaterian offshoots, the phylogenetic position of this taxon still is a matter of ongoing debate. In this contribution, we review recent attempts to contribute phylogenetic information on the Chaetognatha by analysing structure and development of their nervous system (neurophylogeny). Analysing this group of organisms also has a major impact on our understanding of nervous system evolution in Bilateria. We review recent evidence from this field and suggest that Urbilateria already was equipped with the genetic toolkit required to build a complex, concentrated central nervous system (CNS), although this was not expressed phenotypically so that Urbilateria was equipped with a nerve plexus and not a CNS. This implies that in the deep metazoan nodes, concentration of the ancestral plexus occurred twice independently, namely once after the protostome,deuterostome split on the branch leading to the protostomes (resulting in a ventrally positioned nerve cord) and once along the chordate line (with a dorsal nerve cord). [source] Phylogenetic beta diversity: linking ecological and evolutionary processes across space in timeECOLOGY LETTERS, Issue 12 2008Catherine H. Graham Abstract A key challenge in ecological research is to integrate data from different scales to evaluate the ecological and evolutionary mechanisms that influence current patterns of biological diversity. We build on recent attempts to incorporate phylogenetic information into traditional diversity analyses and on existing research on beta diversity and phylogenetic community ecology. Phylogenetic beta diversity (phylobetadiversity) measures the phylogenetic distance among communities and as such allows us to connect local processes, such as biotic interactions and environmental filtering, with more regional processes including trait evolution and speciation. When combined with traditional measures of beta diversity, environmental gradient analyses or ecological niche modelling, phylobetadiversity can provide significant and novel insights into the mechanisms underlying current patterns of biological diversity. [source] Is there more assimilation in Catalonia than in the Basque Country?EUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 6 2008Analysing dynamics of assimilation in nationalist contexts This article builds on recent attempts in political science to illuminate the ,micro-level' mechanisms of identity formation. It analyses the dynamics of assimilation in two similar contexts with extremely salient regional-nationalist movements: Catalonia and the Basque Country. It poses the question: In which of the two regions has there been more assimilation of demographically significant, internal-immigrant segments of the population? It tests whether there has been more assimilation in Catalonia , a result expected from the allegedly more ,civic' nature of the nationalist movement there. To do so, it draws on and goes beyond the tools provided by David Laitin for operationalising assimilation. It uses existing public opinion surveys to construct and present assimilation indices for both regions. The authors show that though rates of ,linguistic adaptation' are higher in Catalonia, such adaptation correlates weakly with assimilation into feelings of subjective identification and the espousal of nationalist views and aspirations more generally. The article goes on to demonstrate that rates of assimilation, when measured using several more robust proxies for the feeling of national identity, are actually lower in Catalonia. The authors then proceed to provide a theoretical explanation for their surprising empirical results. The explanation stresses the causal role of institutional pressures , themselves the product of nationalist coalition-building strategies , in accounting for patterns of linguistic adaptation and of cultural assimilation. Furthermore, it emphasises the relevance of ,cultural demography', particularly among natives/insiders, in accounting for the different nationalist strategies and the different intensity as well as different types of institutional pressures faced by immigrants/outsiders in the two regions. [source] Power, norms and institutional change in the European Union: The protection of the free movement of goodsEUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 2 2003Dionyssis G. Dimitrakopoulos How do European Union (EU) institutions change? Using an institutionalist approach, this article highlights the interplay between power, cognitive limits and the normative order that underpins institutional settings and assesses their impact upon the process of institutional change. Empirical evidence from recent attempts to reinforce the protection of the free movement of goods in the EU suggests that, under conditions of uncertainty, actors with ambiguous preferences assess attempts at institutional change on the basis of the historically defined normative order which holds a given institutional structure together. Hence, path dependent and incremental change occurs even when more ambitious and functionally superior proposals are on offer. [source] Current status of Kluyveromyces systematicsFEMS YEAST RESEARCH, Issue 5 2007Marc-André Lachance Abstract A brief outline of the current taxonomic status of the genus Kluyveromyces is presented. Noteworthy are the transfer of several former Kluyveromyces species to other genera, the retention of the name Kluyveromyces for K. lactis, K. marxianus, and four related species, and some recent attempts to clarify the variety status of strains assigned to K. lactis. [source] String and supergravity motivated cosmologyFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 7-8 2005Article first published online: 30 JUN 200, R. Kallosh In this pedagogical lecture we explain some basic part of the standard cosmological model which is most relevant for the fundamental theoretical physics. We stress the common features and differences between early universe inflation and late-time acceleration. We than proceed with some recent attempts to address the issues of cosmology in string theory and higher dimensional supergravity with the emphasis on successes and still unsolved problems. [source] Decolonising, Multiplicities and Mining in the Eastern Goldfields, Western AustraliaGEOGRAPHICAL RESEARCH, Issue 1 2003Leah M. Gibbs In this ,postcolonial' era, peoples and places around the globe continue to face ongoing colonisation. Indigenous peoples in particular experience colonisation in numerous forms. Despite recent attempts to ,decolonise' indigenous spaces, hegemonic systems of production, governance and thinking often perpetuate colonial structures and relationships, resulting in further entrenched colonisation or ,deep colonising' (Rose, 1999). The interface between indigenous communities and the mining industry provides fertile ground for the tensions emerging between decolonising and deep colonising. Gold mining operations at Placer Dome's Granny Smith mine in the Eastern Goldfields of Western Australia present a valuable case study for examining this tension. Changes taking place at the mine site are decolonising in intent, though outcomes may be deep colonising in effect. Recent discussions among cultural geographers over meanings of place, Ollman's (1993) notion of vantage point and a broadly postcolonial literature inform consideration of this tension. Acknowledgment and incorporation of multiple vantage points into new resource management systems allows current hegemonic approaches to be rethought, and provides insights for the shift towards genuinely decolonising processes. [source] The role of the intestine in the pathophysiology and management of severe acute pancreatitisHPB, Issue 2 2003RS Flint Background The outcome of severe acute pancreatitis has scarcely improved in 10 years. Further impact will require new paradigms in pathophysiology and treatment. There is accumulating evidence to support the concept that the intestine has a key role in the pathophysiology of severe acute pancreatitis which goes beyond the notion of secondary pancreatic infection. Intestinal ischaemia and reperfusion and barrier failure are implicated in the development of multiple organ failure. Discussion Conventional management of severe acute pancreatitis has tended to ignore the intestine. More recent attempts to rectify this problem have included 1) resuscitation aimed at restoring intestinal blood flow through the use of appropriate fluids and splanchnic-sparing vasoconstrictors or inotropes; 2) enteral nutrition to help maintain the integrity of the intestinal barrier; 3) selective gut decontamination and prophylactic antibiotics to reduce bacterial translocation and secondary infection. Novel therapies are being developed to limit intestinal injury, and these include antioxidants and anti-cytokine agents. This paper focuses on the role of the intestine in the pathogenesis of severe acute pancreatitis and reviews the implications for management. [source] Application of possibility theory in the life-cycle inventory assessment of biofuelsINTERNATIONAL JOURNAL OF ENERGY RESEARCH, Issue 8 2002Raymond R. Tan Abstract Data uncertainty issues have constrained the widespread acceptance of life-cycle analysis (LCA) and related methods. This is particularly important in the LCA of fuels due to the wide range of available feedstocks and processing options. Despite recent attempts at standardization, there remain persistent doubts about the general validity of LCA results, often due to uncertainties about data quality. This paper demonstrates the application of possibility theory as a tool for handling life-cycle inventory data imprecision for the case of the net energy balance of coconut methyl ester (CME) as a biodiesel transport fuel. Results derived using a possibililistic computation are contrasted with those arrived at by probabilistic (Monte Carlo) simulation. The two approaches yield comparable results but possibilistic modelling offers significant advantages with respect to computational efficiency. The net energy balance of CME is estimated to be approximately 36 MJ kg,1, significantly higher than the 28 MJ kg,1 net energy typical of rapeseed oil methyl ester (RME) relevant to the U.K. Copyright © 2002 John Wiley & Sons, Ltd. [source] Linkage Disequilibrium Mapping of Disease Susceptibility Genes in Human PopulationsINTERNATIONAL STATISTICAL REVIEW, Issue 1 2000David Clayton Summary The paper reviews recent work on statistical methods for using linkage disequilibrium to locate disease susceptibility genes, given a set of marker genes at known positions in the genome. The paper starts by considering a simple deterministic model for linkage disequilibrium and discusses recent attempts to elaborate it to include the effects of stochastic influences, of "drift", by the use of either Writht-Fisher models or by approaches based on the coalescence of the genealogy of the sample of disease chromosomes. Most of this first part of the paper concerns a series of diallelic markers and, in this case, the models so far proposed are hierarchical probability models for multivariate binary data. Likelihoods are intractable and most approaches to linkage disequilibrium mapping amount to marginal models for pairwise associations between individual markers and the disease susceptibility locus. Approaches to evalutation of a full likelihood require Monte Carlo methods in order to integrate over the large number of unknowns. The fact that the initial state of the stochastic process which has led to present-day allele frequencies is unknown is noted and its implications for the hierarchical probability model is discussed. Difficulties and opportunities arising as a result of more polymorphic markers and extended marker haplotypes are indicated. Connections between the hierarchical modelling approach and methods based upon identity by descent and haplotype sharing by seemingly unrelated case are explored. Finally problems resulting from unknown modes of inheritance, incomplete penetrance, and "phenocopies" are briefly reviewed. Résumé Ce papier est une revue des travaux récents, protant sur les méthodes statistiques qui utilisent I'étude, des liaisons désé, quilib rées, pour identifer les génes, de susceptibilité des maladies,ápartir d'une série, de marqueurs de géncs á des positions définies du génome,. Le papier commence par considérer, un modéle, détéministe, simple pour liaisons déséquilibr,ées, puis nous discutons les améliorations, ré centes proposées, de ce modéle, dans but de tenir compte des effects des influences stochastiques soit en utilisant les modéles, de wright-fisher, soit par des approches basées, sur la coalescence de la géné alogic de I'échantillon, des chromosomes malades. La plupart de cette premiére, partie porte sur une série, de marqueurs dialléliques et, dans ce cas, les modéles, proposés, sont des modéles, hiérerchiques, probabilistes pour dinnées, binaires multivariées. Les viaisemblances n'ont pas de forme analytique et la plupart des approches pour la cartographie des liaisons déséquilibrées, sont équivalentes aux modéles, marginaux pour dinnées, appariées, entre des marqueurs individuels et le géne, de susceptibilité de la maladie.Pour évaluer, la vriausemblance compléte, des méthodes de Monte carlo sont nécessaires, afin d'intégrer, le large nombre d; inconnues. Le fait que l'état, initial du process stochastique qui a conduit éla fré, quence, allélique, actuel soit inconnu est á noter et ses implications pour le modéle, hiérarchique, probabiliste sont discutées.Les difficultés, et implications issues de marqueurs polumorphiques et de marquers haplotypes sont dévéloppées.Les liens entire l'approche de modélisation, hiérerchique, et les méthodes, d'analyse d'identite pardescendance et les haplotypes partagés, par des cas apparement non apparentés, sont explorés. Enfin les problémes, relatifs à des modes de transmission inconnus,à des pénétrances, incomplé, tes, et aux "phénocopies" sont briévenment evoqués. [source] Time-dependent density functional theory for nonadiabatic processesISRAEL JOURNAL OF CHEMISTRY, Issue 1-2 2005Roi Baer Time-dependent density functional theory (TDDFT) is a general and robust method allowing the study of electron dynamics whether induced by nuclear motion or by external fields. We give a brief overview of the theory and some numerical methods together with recent applications stressing the generality and wide applicability of the method. We also discuss recent attempts to extend the present TDDFT by incorporating memory terms into the exchange correlation potentials. [source] Partially Hydrogenated 1,1,-Binaphthyl as Ligand Scaffold in Metal-Catalyzed Asymmetric SynthesisADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 5 2003T.-L., Terry Abstract Although chiral binaphthyl-type ligands are already known to be effective over a broad spectrum of reactions, they sometimes fail in providing high enantioselectivities in some catalytic asymmetric reactions. This article summarizes recent attempts to elevate their performance by partly hydrogenating the naphthyl components of the binaphthyl. The synthetic routes to some of these ligands are briefly outlined. Positive results are observed in asymmetric hydrogenation, alkylation, borane reduction, epoxidation and hetero-Diels,Alder reactions. The function of the partially reduced binaphthyl skeleton, however, can sometimes be disadvantageous or ambiguous as illustrated in reactions such as asymmetric ring-closing metathesis, 1,4-conjugate addition, epoxidation, allylic alkylation, trimethylsilylcyanation, epoxide ring-opening and hydroformylation. [source] Assessing the distortionary impact of state trading in ChinaAGRICULTURAL ECONOMICS, Issue 3-4 2010Steve McCorriston Trade policy; State trading enterprises; China Abstract State trading is a common feature in the management of imports and exports of agricultural products and it has been a long-standing feature of China's agricultural trade regime. While the use of state trading was modified by China's accession to the WTO, it remains a dominant feature for some commodities, even though there have been recent attempts to diminish its importance. In this article, we review the role that the state trading enterprise (STE), China National Cereals, Oils and Foodstuffs Import and Export Company (COFCO), continues to play in the importing and exporting of some agricultural commodities. We then review the economic theory that has been developed to measure the tariff equivalent of importing STEs. Finally, we apply that theory through a calibration exercise to measure the tariff equivalent of COFCO in China's import market for wheat. The distortionary impact of COFCO depends on the bias in government policy toward agriculture, the competitiveness of the domestic procurement market, and also the number of firms that are allocated licenses to import alongside COFCO. [source] Molecular imprinting science and technology: a survey of the literature for the years up to and including 2003JOURNAL OF MOLECULAR RECOGNITION, Issue 2 2006Cameron Alexander Abstract Over 1450 references to original papers, reviews and monographs have herein been collected to document the development of molecular imprinting science and technology from the serendipitous discovery of Polyakov in 1931 to recent attempts to implement and understand the principles underlying the technique and its use in a range of application areas. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by papers dealing with fundamental aspects of molecular imprinting and the development of novel polymer formats. Thereafter, literature describing attempts to apply these polymeric materials to a range of application areas is presented. Copyright © 2006 John Wiley & Sons, Ltd. 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