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Selected AbstractsNational Adoption of International Accounting Standards: An Institutional PerspectiveCORPORATE GOVERNANCE, Issue 3 2010William Judge ABSTRACT Manuscript Type: Empirical Research Question/Issue: Effective corporate governance requires accurate and reliable financial information. Historically, each nation has developed and pursued its own financial standards; however, as financial markets consolidate into a global market, there is a need for a common set of financial standards. As a result, there is a movement towards harmonization of international financial reporting standards (IFRS) throughout the global economy. While there has been considerable research on the effects of IFRS adoption, there has been relatively little systematic study as to the antecedents of IFRS adoption. Consequently, this study seeks to understand why some economies have quickly embraced IFRS standards while others partially adopt IFRS and still others continue to resist. Research Findings/Results: After controlling for market capitalization and GDP growth, we find that foreign aid, import penetration, and level of education achieved within a national economy are all predictive of the degree to which IFRS standards are adopted across 132 developing, transitional and developed economies. Theoretical/Academic Implications: We found that all three forms of isomorphic pressures (i.e., coercive, mimetic, and normative) are predictive of IFRS adoption. Consequently, institutional theory with its emphasis on legitimacy-seeking by social actors was relatively well supported by our data. This suggests that the IFRS adoption process is driven more by social legitimization pressures, than it is by economic logic. Practitioner/Policy Implications: For policy makers, our findings suggest that the institutional pressures within an economy are the key drivers of IFRS adoption. Consequently, policy makers should seek to influence institutional pressures that thwart and/or enhance adoption of IFRS. For executives of multinational firms, our findings provide insights that can help to explain and predict future IFRS adoption within economies where their foreign subsidiaries operate. This ability could be useful for creating competitive advantages for foreign subsidiaries where IFRS adoption was resisted, or avoiding competitive disadvantages for foreign subsidiaries unfamiliar with IFRS standards. [source] Mechanisms of Epileptogenesis in Tuberous Sclerosis Complex and Related Malformations of Cortical Development with Abnormal Glioneuronal ProliferationEPILEPSIA, Issue 1 2008Michael Wong Summary Malformations of cortical development (MCDs) are increasingly recognized as causes of medically intractable epilepsy. In order to develop more effective, rational therapies for refractory epilepsy related to MCDs, it is important to achieve a better understanding of the underlying mechanisms of epileptogenesis, but this is complicated by the wide variety of different radiographic, histopathological, and molecular features of these disorders. A subset of MCDs share a number of characteristic cellular and molecular abnormalities due to early defects in neuronal and glial proliferation and differentiation and have a particularly high incidence of epilepsy, suggesting that this category of MCDs with abnormal glioneuronal proliferation may also share a common set of primary mechanisms of epileptogenesis. This review critically analyzes both clinical and basic science evidence for overlapping mechanisms of epileptogenesis in this group of disorders, focusing on tuberous sclerosis complex, focal cortical dysplasia with balloon cells, and gangliogliomas. Specifically, the role of lesional versus perilesional regions, circuit versus cellular/molecular defects, and nonneuronal factors, such as astrocytes, in contributing to epileptogenesis in these MCDs is examined. An improved understanding of these various factors involved in epileptogenesis has direct clinical implications for optimizing current treatments or developing novel therapeutic approaches for epilepsy in these disorders. [source] Cocaine Rapid Efficacy Screening Trials (CREST): lessons learnedADDICTION, Issue 2005Kyle M. Kampman ABSTRACT Aims The Cocaine Rapid Efficacy Screening Trials (CREST) were designed by the National Institute on Drug Abuse Division of Treatment Research and Development (NIDA, DT R&D) to rapidly screen a number of medications potentially useful for the treatment of cocaine dependence. Design Each CREST trial was designed to compare several medications in a single trial against an unmatched placebo. The placebo group was included in each trial to avoid the nearly universal positive response to medications seen in open-label trials. In addition, a common set of procedures and outcome measures were employed throughout to increase comparability of results obtained from different trials and from different times. Participants In all, 18 medications were screened in seven different trials, conducted in four different sites throughout the United States involving 398 cocaine-dependent patients. Findings Three medications were found to be promising enough to include in subsequent larger trials. Common statistical procedures for evaluating medications were developed to facilitate comparisons across sites and across time. A portion of the data were pooled and analyzed, which yielded some useful insights into cocaine dependence and its treatment. Finally, a review of individual trials together with the pooled analysis revealed several potential improvements for future screening trials. Conclusions Overall, the CREST trials proved to be useful for rapidly screening medications for treatment of cocaine dependence, but several modifications in design should be made before this framework is applied further. [source] Unconventional Spin Crossover in Dinuclear and Trinuclear Iron(III) Complexes with Cyanido and Metallacyanido BridgesEUROPEAN JOURNAL OF INORGANIC CHEMISTRY, Issue 21 2009alitro Abstract A nonsymmetrical triamine, 1,6-diamino-4-azahexane, was Schiff-condensed with (X-substituted) o -salicylaldehyde to yield pentadentate ligands X-L5: salpet and MeBu-salpet. These ligands form mononuclear, dinuclear, and trinuclear FeIII complexes, whose structures were determined by single-crystal X-ray analysis. Of the mononuclear complexes, [FeIII(salpet)Cl] and [FeIII(MeBu-salpet)Cl] are high spin (S = 5/2), whereas [FeIII(salpet)CN]·MeOH is low spin (S = 1/2). The dinuclear and trinuclear complexes show a kind ofthermally induced spin crossover. The dinuclear complex [L5FeIII(CN)FeIIIL5](ClO4)·2H2O (L5 = salpet) is a mixed-spin assembly: the C -coordinated FeIII center is low spin (L) and the N -coordinated FeIII center is high spin (H) at low temperature; an antiferromagnetic interaction occurs between them. This LH reference state is mixed with the LL one. Upon heating, the system shows an increasing content of the HH state. Also, the dinuclear complex [L5FeIII(CN)FeIIIL5](BPh4)·2MeCN (L5 = MeBu-salpet) exhibits a spin transition between LH and HH spin pairs. The mixed-valence trinuclear complex [L5FeIII{FeII(CN)5(NO)}FeIIIL5]·0.5MeOH·3.75H2O (L5 = salpet) shows spin crossover with a residual high-spin fraction at liquid He temperature owing to the LL + LH ground state. The metallacyanido-bridged complex [L5FeIII{Ni(CN)4}FeIIIL5]·2MeOH (L5 = MeBu-salpet) contains a high-spin pair, HH, over the whole temperature interval with a ferromagnetic exchange interaction. A theoretical model was outlined that allows simultaneous fitting of all available experimental data (magnetic susceptibility, magnetization, high-spin mole fraction obtained from the Mössbauer spectra) on a common set of parameters. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Identification and characterization of cytochrome bc1 subcomplexes in mitochondria from yeast with single and double deletions of genes encoding cytochrome bc1 subunitsFEBS JOURNAL, Issue 17 2007Vincenzo Zara We have examined the status of the cytochrome bc1 complex in mitochondrial membranes from yeast mutants in which genes for one or more of the cytochrome bc1 complex subunits were deleted. When membranes from wild-type yeast were resolved by native gel electrophoresis and analyzed by immunodecoration, the cytochrome bc1 complex was detected as a mixed population of enzymes, consisting of cytochrome bc1 dimers, and ternary complexes of cytochrome bc1 dimers associated with one and two copies of the cytochrome c oxidase complex. When membranes from the deletion mutants were resolved and analyzed, the cytochrome bc1 dimer was not associated with the cytochrome c oxidase complex in many of the mutant membranes, and membranes from some of the mutants contained a common set of cytochrome bc1 subcomplexes. When these subcomplexes were fractionated by SDS/PAGE and analyzed with subunit-specific antibodies, it was possible to recognize a subcomplex consisting of cytochrome b, subunit 7 and subunit 8 that is apparently associated with cytochrome c oxidase early in the assembly process, prior to acquisition of the remaining cytochrome bc1 subunits. It was also possible to identify a subcomplex consisting of subunit 9 and the Rieske protein, and two subcomplexes containing cytochrome c1 associated with core protein 1 and core protein 2, respectively. The analysis of all the cytochrome bc1 subcomplexes with monospecific antibodies directed against Bcs1p revealed that this chaperone protein is involved in a late stage of cytochrome bc1 complex assembly. [source] Genetic association tests in the presence of epistasis or gene-environment interactionGENETIC EPIDEMIOLOGY, Issue 7 2008Kai WangArticle first published online: 24 APR 200 Abstract A genetic variant is very likely to manifest its effect on disease through its main effect as well as through its interaction with other genetic variants or environmental factors. Power to detect genetic variants can be greatly improved by modeling their main effects and their interaction effects through a common set of parameters or "generalized association parameters" (Chatterjee et al. [2006] Am. J. Hum. Genet. 79:1002,1016) because of the reduced number of degrees of freedom. Following this idea, I propose two models that extend the work by Chatterjee and colleagues. Particularly, I consider not only the case of relatively weak interaction effect compared to the main effect but also the case of relatively weak main effect. This latter case is perhaps more relevant to genetic association studies. The proposed methods are invariant to the choice of the allele for scoring genotypes or the choice of the reference genotype score. For each model, the asymptotic distribution of the likelihood ratio statistic is derived. Simulation studies suggest that the proposed methods are more powerful than existing ones under certain circumstances. Genet. Epidemiol. 2008. © 2008 Wiley-Liss, Inc. [source] Contextual Determinants of Reward Systems' Success: An Exploratory StudyHUMAN RESOURCE MANAGEMENT, Issue 3 2001Charles H. Fay Data were collected on successful and unsuccessful reward initiatives. The initiatives included new and modified base pay, short- and long-term incentive, benefits, and perquisite/lifestyle rewards. Initiative success was measured on seven factors, and ten conditions were measured for initiative success. Follow-up telephone calls to most respondents provided more detail for examples. Analysis suggests that a common set of criteria can be used to judge the success of different kinds of programs. Surprisingly, success in plan design was not a significant explanatory variable in reaching success on any criterion of rewards initiative success. © 2001 John Wiley & Sons, Inc. [source] The early promotion and intervention research consortium (E-PIRC): Five approaches to improving infant/toddler mental health in Early Head StartINFANT MENTAL HEALTH JOURNAL, Issue 2 2007Linda S. Beeber One planned consequence of the national Infant Mental Health Forum held in the United States in 2000 was the funding of five research projects conducted in Early Head Start (EHS) programs. Each project strengthened existing programs by integrating infant/toddler mental health approaches and testing the outcomes on infant/toddler development, behavior, and parent-child interactions. In two of the projects, the effect of offering enrichment for EHS staff was tested. The other three projects tested the effect of services offered directly to parents and children. This article describes the five projects and the theories, methods, and outcome measures used. In order to understand more fully the elevated risk factors in these families and the consequences for mental health in their infants and toddlers, a common set of measures was developed. Data have been used to explore the common threats to mental health and the factors that moderate the impact on infants and toddlers. [source] Email Flaming Behaviors and Organizational ConflictJOURNAL OF COMPUTER-MEDIATED COMMUNICATION, Issue 1 2008Anna K. Turnage This study explores whether the attributes listed in the literature on flaming in email are considered characteristic of flaming by actual email users. Through the creation of a semantic differential scale,called the Message Invectives Scale,the study took eight concepts found in more than 20 research articles on flaming and examined email users' responses to a set of 20 messages in relation to those eight characteristics. Findings indicate that in each of the 20 cases, six of the original eight concepts relate to each other to form a common set, which also correlates positively with perceptions of flaming. Some of the messages that scored high for flaming contained profanity, all capital letters, excessive exclamation points or question marks, indicating that these attributes also relate to flaming. Based on these findings, recommendations are advanced as to how email should be used to avoid negative attributes that can lead to organizational conflict. [source] OPTIMIZATION CRITERIA FOR BATCH RETORT BATTERY DESIGN AND OPERATION IN FOOD CANNING-PLANTSJOURNAL OF FOOD PROCESS ENGINEERING, Issue 6 2003R. SIMPSON ABSTRACT Optimization of thermal processing in the commercial sterilization of canned foods is of great interest because the canning industry plays an important role within the economy of the food processing sector. Many food canning plants operate in a batch mode with a battery of individual batch retorts. The aim of this study was to propose and analyze several criteria and methodologies for optimum design and operation of such retort systems. Two criteria were proposed in the case of choosing the optimum number of retorts to be installed when designing a new batch-operated canning line. The third criterion dealt with seeking optimum process conditions for maximizing output from a fixed number of retorts when processing small batches of different products and container sizes. In the case of new plant design optimization, one objective was to determine the optimum number of retorts that would minimize on-going processing costs related to labor and energy. Retort scheduling (programming) was studied from which a simple mathematical expression was derived for this purpose. A second objective was to determine the optimum number of retorts that would maximize the net present value of initial investment. Approaches based upon engineering economics were studied from which to develop a mathematical procedure for this purpose. In the case of maximizing output from a fixed number of retorts for different products and container sizes, isolethal processes were identified for various product/containers from which a common set of process conditions could be chosen for simultaneous processing of different product lots in the same retort. [source] Segregated targeting for multiple resource networks using decomposition algorithmAICHE JOURNAL, Issue 5 2010Santanu Bandyopadhyay Abstract A generalized decomposition technique is presented for determining optimal resource usage in segregated targeting problems with single quality index (e.g., concentration, temperature, etc.) through pinch analysis. The latter problems are concerned with determining minimal resource requirements of process networks characterized by the existence of multiple zones, each consisting of a set of demands and using a unique external resource. However, all the zones share a common set of internal sources. The decomposition algorithm allows the problem to be decomposed into a sequence of subproblems, each of which can in turn be solved using any established graphical or algebraic targeting methodology to determine the minimum requirement of respective resource. This article presents a rigorous mathematical proof of the decomposition algorithm, and then demonstrates its potential applications with case studies on carbon-constrained energy sector planning, interplant water integration, and emergy-based multisector fuel allocation. © 2009 American Institute of Chemical Engineers AIChE J, 2010 [source] Future Prospects for Biomarkers of Alcohol Consumption and Alcohol-Induced DisordersALCOHOLISM, Issue 6 2010Willard M. Freeman The lack of reliable measures of alcohol intake is a major obstacle to the diagnosis, treatment, and research of alcohol abuse and alcoholism. Successful development of a biomarker that allows for accurate assessment of alcohol intake and drinking patterns would not only be a major advance in clinical care but also a valuable research tool. A number of advances have been made in testing the validity of proposed biomarkers as well as in identifying potential new biomarkers through systems biology approaches. This commentary will examine the definition of a biomarker of heavy drinking, the types of potential biomarkers, the steps in biomarker development, the current state of biomarker development, and critical obstacles for the field. The challenges in developing biomarkers for alcohol treatment and research are similar to those found in other fields. However, the alcohol research field must reach a competitive level of rigor and organization. We recommend that NIAAA consider taking a leadership role in organizing investigators in the field and providing a common set of clinical specimens for biomarker validation studies. [source] Evaluating Acute Musculoskeletal ComplaintsJOURNAL OF THE AMERICAN ACADEMY OF NURSE PRACTITIONERS, Issue 5 2001Mary Jo Goolsby EdD Clinical practice guidelines (CPG) are now widely available summarizing large amounts of scientific evidence and providing specific recommendations for the evaluation, diagnosis, and management of varied health problems. In order to take advantage of the available CPGs in clinical practice, providers must be aware of their existence and be able to critique them for scientific merit and relevance to specific clinical settings. This ongoing series is designed to provide a brief review of a different CPG each month. This month, the CPG reviewed addresses the evaluation of an extremely common set of complaints: musculoskeletal symptoms. The document emphasizes the importance of a thorough history and physical for these presentations and indicates when specific diagnostic studies and/or consultations are warranted. [source] Quality of Reporting of Clinical Trials of Dogs and Cats and Associations with Treatment EffectsJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2010J.M. Sargeant Background: To address concerns about the quality of reporting of randomized controlled trials, and the potential for biased treatment effects in poorly reported trials, medical journals have adopted a common set of reporting guidelines, the Consolidated Standards of Reporting Trials (CONSORT) statement, to improve the reporting of randomized controlled trials. Hypothesis: The reporting of clinical trials involving dogs and cats might not be ideal, and this might be associated with biased treatment effects. Animals: Dogs and cats used in 100 randomly selected reports of clinical trials. Methods: Data related to methodological quality and completeness of reporting were extracted from each trial. Associations between reporting of trial features and the proportion of positive treatment effects within trials were evaluated by generalized linear models. Results: There were substantive deficiencies in reporting of key trial features. An increased proportion of positive treatment effects within a trial was associated with not reporting: the method used to generate the random allocation sequence (P < .001), the use of double blinding (P < .001), the inclusion criteria for study subjects (P= .003), baseline differences between treatment groups (P= .006), the measurement used for all outcomes (P= .002), and possible study limitations (P= .03). Conclusions and Clinical Importance: Many clinical trials involving dogs and cats in the literature do not report details related to methodological quality and aspects necessary to evaluate external validity. There is some evidence that these deficiencies are associated with treatment effects. There is a need to improve reporting of clinical trials, and guidelines, such as the CONSORT statement, can provide a valuable tool for meeting this need. [source] Characterization of TetD as a transcriptional activator of a subset of genes of the Escherichia coli SoxS/MarA/Rob regulonMOLECULAR MICROBIOLOGY, Issue 4 2005Kevin L. Griffith Summary In Escherichia coli, SoxS, MarA and Rob form a closely related subset of the AraC/XylS family of positive regulators, sharing ,42% amino acid sequence identity over the length of SoxS and the ability to activate transcription of a common set of target genes that provide resistance to redox-cycling compounds and antibiotics. On the basis of its ,43% amino acid sequence identity with SoxS, MarA and Rob, TetD, encoded by transposon Tn10, appears to be a fourth member of the subset. However, although its expression has been shown to be negatively regulated by TetC and not inducible by tetracycline, the physiological function of TetD is unknown. Accordingly, in the work presented here, we initiate a molecular characterization of TetD. We show that expression of TetD activates transcription of a subset of the SoxS/MarA/Rob regulon genes and confers resistance to redox-cycling compounds and antibiotics. We show that mutations in the putative TetD binding site of a TetD-activatable promoter and a mutation in the protein's N-terminal DNA recognition helix interfere with transcription activation, thereby indicating that TetD directly activates target gene transcription. Finally, we show that TetD, like SoxS and MarA, is intrinsically unstable; however, unlike SoxS and MarA, TetD is not degraded by Lon or any of the cell's known cytoplasmic ATP-dependent proteases. Thus, we conclude that TetD is a bona fide member of the SoxS/MarA/Rob subfamily of positive regulators. [source] Allocation of quality improvement targets based on investments in learningNAVAL RESEARCH LOGISTICS: AN INTERNATIONAL JOURNAL, Issue 8 2001Herbert Moskowitz Abstract Purchased materials often account for more than 50% of a manufacturer's product nonconformance cost. A common strategy for reducing such costs is to allocate periodic quality improvement targets to suppliers of such materials. Improvement target allocations are often accomplished via ad hoc methods such as prescribing a fixed, across-the-board percentage improvement for all suppliers, which, however, may not be the most effective or efficient approach for allocating improvement targets. We propose a formal modeling and optimization approach for assessing quality improvement targets for suppliers, based on process variance reduction. In our models, a manufacturer has multiple product performance measures that are linear functions of a common set of design variables (factors), each of which is an output from an independent supplier's process. We assume that a manufacturer's quality improvement is a result of reductions in supplier process variances, obtained through learning and experience, which require appropriate investments by both the manufacturer and suppliers. Three learning investment (cost) models for achieving a given learning rate are used to determine the allocations that minimize expected costs for both the supplier and manufacturer and to assess the sensitivity of investment in learning on the allocation of quality improvement targets. Solutions for determining optimal learning rates, and concomitant quality improvement targets are derived for each learning investment function. We also account for the risk that a supplier may not achieve a targeted learning rate for quality improvements. An extensive computational study is conducted to investigate the differences between optimal variance allocations and a fixed percentage allocation. These differences are examined with respect to (i) variance improvement targets and (ii) total expected cost. For certain types of learning investment models, the results suggest that orders of magnitude differences in variance allocations and expected total costs occur between optimal allocations and those arrived at via the commonly used rule of fixed percentage allocations. However, for learning investments characterized by a quadratic function, there is surprisingly close agreement with an "across-the-board" allocation of 20% quality improvement targets. © John Wiley & Sons, Inc. Naval Research Logistics 48: 684,709, 2001 [source] Proteomic profiling of exosomes: Current perspectivesPROTEINS: STRUCTURE, FUNCTION AND BIOINFORMATICS, Issue 19 2008Richard J. Simpson Professor Abstract Exosomes are 40,100,nm membrane vesicles of endocytic origin secreted by most cell types in vitro. Recent studies have shown that exosomes are also found in vivo in body fluids such as blood, urine, amniotic fluid, malignant ascites, bronchoalveolar lavage fluid, synovial fluid, and breast milk. While the biological function of exosomes is still unclear, they can mediate communication between cells, facilitating processes such as antigen presentation and in trans signaling to neighboring cells. Exosome-like vesicles identified in Drosophila (referred to as argosomes) may be potential vehicles for the spread of morphogens in epithelia. The advent of current MS-based proteomic technologies has contributed significantly to our understanding of the molecular composition of exosomes. In addition to a common set of membrane and cytosolic proteins, it is becoming increasingly apparent that exosomes harbor distinct subsets of proteins that may be linked to cell-type associated functions. The secretion of exosomes by tumor cells and their implication in the transport and propagation of infectious cargo such as prions and retroviruses such as HIV suggest their participation in pathological situations. Interestingly, the recent observation that exosomes contain both mRNA and microRNA, which can be transferred to another cell, and be functional in that new environment, is an exciting new development in the unraveling exosome saga. The present review aims to summarize the physical properties that define exosomes as specific cell-type secreted membrane vesicles. [source] Interlocal Service Cooperation in U.S. Cities: A Social Network ExplanationPUBLIC ADMINISTRATION REVIEW, Issue 2 2010Kelly LeRoux Local governments increasingly confront policy problems that span the boundaries of individual political jurisdictions. Institutional theories of local governance and intergovernmental relations emphasize the importance of networks for fostering service cooperation among local governments. Yet empirical research fails to examine systematically the effects of social networks on interlocal service cooperation. Do the individual networks of local government actors increase their jurisdiction's level of interlocal service delivery? Drawing data from the National Administrative Studies Project IV (NASP-IV), multivariate analysis is applied to examine this question among 919 municipal managers and department heads across the United States. The findings indicate that interlocal service cooperation increases when jurisdictional actors network frequently through a regional association or council of government and when they are united by a common set of professional norms and disciplinary values. Manager participation in professional associations, however, does not increase interjurisdictional cooperation. The key conclusion for local government practitioners searching for ways to increase collaboration: networks that afford opportunities for more face-to-face interaction yield better results for effective service partnerships. [source] The prevalence of autistic spectrum disorders in adolescents with a history of specific language impairment (SLI)THE JOURNAL OF CHILD PSYCHOLOGY AND PSYCHIATRY AND ALLIED DISCIPLINES, Issue 6 2006Gina Conti-Ramsden Background:, Traditionally, autism and specific language impairment (SLI) have been regarded as distinct disorders but, more recently, evidence has been put forward for a closer link between them: a common set of language problems, in particular receptive language difficulties and the existence of intermediate cases including pragmatic language impairment. The present study aimed to examine the prevalence of autism spectrum disorders in a large sample of adolescents with a history of SLI. Method:, The presence of autism spectrum disorders was examined in seventy-six 14-year-olds with a confirmed history of SLI. A variety of instruments were employed, including the Autism Diagnostic Interview-Revised (ADI-R), the Autism Diagnostic Observation Schedule (ADOS) and the Family History Interview (FHI). Results:, The prevalence of autism spectrum disorders in young people with SLI was found to be 3.9%, about 10 times what would be expected from the general population. In addition, a much larger number of young people with a history of SLI showed only some autism spectrum symptoms or showed them in a mild form. Conclusions:, Young people with SLI have an increased risk of autism. The magnitude of this risk is considerable. In addition, a larger proportion (a quarter of individuals) present with a number of behaviours consistent with autism spectrum disorders. [source] Joining the Pillars of Hercules: mtDNA Sequences Show Multidirectional Gene Flow in the Western MediterraneanANNALS OF HUMAN GENETICS, Issue 4 2003S. Plaza Summary Phylogenetic analysis of mitochondrial DNA (mtDNA) performed in Western Mediterranean populations has shown that both shores share a common set of mtDNA haplogroups already found in Europe and the Middle East. Principal co-ordinates of genetic distances and principal components analyses based on the haplotype frequencies show that the main genetic difference is attributed to the higher frequency of sub-Saharan L haplogroups in NW Africa, showing some gene flow across the Sahara desert, with a major impact in the southern populations of NW Africa. The AMOVA demonstrates that SW European populations are highly homogeneous whereas NW African populations display a more heterogeneous genetic pattern, due to an east-west differentiation as a result of gene flow coming from the East. Despite the shared haplogroups found in both areas, the European V and the NW African U6 haplogroups reveal the traces of the Mediterranean Sea permeability to female migrations, and allowed for determination and quantification of the genetic contribution of both shores to the genetic landscape of the geographic area. Comparison of mtDNA data with autosomal markers and Y-chromosome lineages, analysed in the same populations, shows a congruent pattern, although female-mediated gene flow seems to have been more intense than male-mediated gene flow. [source] Maternal variation in juvenile survival and growth of triploid hybrids between female rainbow trout and male brown trout and brook charrAQUACULTURE RESEARCH, Issue 2 2005J M Blanc Abstract Related sib-groups of rainbow trout × brown trout and rainbow trout × brook charr triploid hybrids and monospecific diploid and triploid rainbow trout controls were obtained from a common set of rainbow trout dams. On the basis of hybrid juvenile performances, 10 sib-groups were selected and the corresponding diploid rainbow trouts were raised up to adult stage. Females from each group of rainbow trout were used to produce a second generation of hybrid progeny, the performances of which were analysed for grandmaternal variation and relation with first-generation relatives. Results showed that hybrid traits (alevin yield and weight, survival and growth of fingerlings) were strongly influenced by maternal origin, and could be correlated to those of rainbow trout controls, but that maternal abilities had a low rate of inheritance. It was concluded that little improvement can be expected through selective breeding within parental populations. [source] Paternal variation in juvenile survival and growth of the triploid hybrid between female rainbow trout (Oncorhynchus mykiss Walbaum) and male brown trout (Salmo trutta L.)AQUACULTURE RESEARCH, Issue 3 2003J M Blanc Abstract Related sib-groups of rainbow trout × brown trout triploid hybrid and monospecific brown trout controls were obtained from a common set of brown trout sires. On the basis of hybrid juvenile survival and growth, 10 sib-groups were selected and the corresponding brown trouts were raised up to adult stage. Males from each group of brown trout were used to produce a second generation of hybrid progeny, the performances of which were analysed for grandpaternal variation and relation with first generation relatives. Results showed that hybrid traits were influenced by paternal and grandpaternal origin, but that there was little relation between hybrids and brown trouts, or between successive generations of hybrids. [source] Recombinant protein expression and solubility screening in Escherichia coli: a comparative studyACTA CRYSTALLOGRAPHICA SECTION D, Issue 10 2006Nick S. Berrow Producing soluble proteins in Escherichia coli is still a major bottleneck for structural proteomics. Therefore, screening for soluble expression on a small scale is an attractive way of identifying constructs that are likely to be amenable to structural analysis. A variety of expression-screening methods have been developed within the Structural Proteomics In Europe (SPINE) consortium and to assist the further refinement of such approaches, eight laboratories participating in the network have benchmarked their protocols. For this study, the solubility profiles of a common set of 96 His6 -tagged proteins were assessed by expression screening in E. coli. The level of soluble expression for each target was scored according to estimated protein yield. By reference to a subset of the proteins, it is demonstrated that the small-scale result can provide a useful indicator of the amount of soluble protein likely to be produced on a large scale (i.e. sufficient for structural studies). In general, there was agreement between the different groups as to which targets were not soluble and which were the most soluble. However, for a large number of the targets there were wide discrepancies in the results reported from the different screening methods, which is correlated with variations in the procedures and the range of parameters explored. Given finite resources, it appears that the question of how to most effectively explore `expression space' is similar to several other multi-parameter problems faced by crystallographers, such as crystallization. [source] Design efficiency for non-market valuation with choice modelling: how to measure it, what to report and why,AUSTRALIAN JOURNAL OF AGRICULTURAL & RESOURCE ECONOMICS, Issue 3 2008Riccardo Scarpa We review the basic principles for the evaluation of design efficiency in discrete choice modelling with a focus on efficiency of WTP estimates from the multinomial logit model. The discussion is developed under the realistic assumption that researchers can plausibly define a prior belief on the range of values for the utility coefficients. D -, A- , B- , S- and C- errors are compared as measures of design performance in applied studies and their rationale is discussed. An empirical example based on the generation and comparison of fifteen separate designs from a common set of assumptions illustrates the relevant considerations to the context of non-market valuation, with particular emphasis placed on C- efficiency. Conclusions are drawn for the practice of reporting in non-market valuation and for future work on design research. [source] Animal performance and stress: responses and tolerance limits at different levels of biological organisationBIOLOGICAL REVIEWS, Issue 2 2009Karin S. Kassahn ABSTRACT Recent advances in molecular biology and the use of DNA microarrays for gene expression profiling are providing new insights into the animal stress response, particularly the effects of stress on gene regulation. However, interpretation of the complex transcriptional changes that occur during stress still poses many challenges because the relationship between changes at the transcriptional level and other levels of biological organisation is not well understood. To confront these challenges, a conceptual model linking physiological and transcriptional responses to stress would be helpful. Here, we provide the basis for one such model by synthesising data from organismal, endocrine, cellular, molecular, and genomic studies. We show using available examples from ectothermic vertebrates that reduced oxygen levels and oxidative stress are common to many stress conditions and that the responses to different types of stress, such as environmental, handling and confinement stress, often converge at the challenge of dealing with oxygen imbalance and oxidative stress. As a result, a common set of stress responses exists that is largely independent of the type of stressor applied. These common responses include the repair of DNA and protein damage, cell cycle arrest or apoptosis, changes in cellular metabolism that reflect the transition from a state of cellular growth to one of cellular repair, the release of stress hormones, changes in mitochondrial densities and properties, changes in oxygen transport capacities and changes in cardio-respiratory function. Changes at the transcriptional level recapitulate these common responses, with many stress-responsive genes functioning in cell cycle control, regulation of transcription, protein turnover, metabolism, and cellular repair. These common transcriptional responses to stress appear coordinated by only a limited number of stress-inducible and redox-sensitive transcription factors and signal transduction pathways, such as the immediate early genes c-fos and c-jun, the transcription factors NF,B and HIF - 1,, and the JNK and p38 kinase signalling pathways. As an example of environmental stress responses, we present temperature response curves at organismal, cellular and molecular levels. Acclimation and physiological adjustments that can shift the threshold temperatures for the onset of these responses are discussed and include, for example, adjustments of the oxygen delivery system, the heat shock response, cellular repair system, and transcriptome. Ultimately, however, an organism's ability to cope with environmental change is largely determined by its ability to maintain aerobic scope and to prevent loss in performance. These systemic constraints can determine an organism's long-term survival well before cellular and molecular functions are disturbed. The conceptual model we propose here discusses some of the crosslinks between responses at different levels of biological organisation and the central role of oxygen balance and oxidative stress in eliciting these responses with the aim to help the interpretation of environmental genomic data in the context of organismal function and performance. [source] Differential Expression and Network Inferences through Functional Data ModelingBIOMETRICS, Issue 3 2009Donatello Telesca Summary Time course microarray data consist of mRNA expression from a common set of genes collected at different time points. Such data are thought to reflect underlying biological processes developing over time. In this article, we propose a model that allows us to examine differential expression and gene network relationships using time course microarray data. We model each gene-expression profile as a random functional transformation of the scale, amplitude, and phase of a common curve. Inferences about the gene-specific amplitude parameters allow us to examine differential gene expression. Inferences about measures of functional similarity based on estimated time-transformation functions allow us to examine gene networks while accounting for features of the gene-expression profiles. We discuss applications to simulated data as well as to microarray data on prostate cancer progression. [source] Common gene expression signatures in t(8;21)- and inv(16)-acute myeloid leukaemiaBRITISH JOURNAL OF HAEMATOLOGY, Issue 3 2006Hitoshi Ichikawa Summary Human acute myeloid leukaemia (AML) involving a core-binding factor (CBF) transcription factor is called CBF leukaemia. In these leukaemias, AML1 (RUNX1, PEBP2,B, CBF,2)-MTG8 (ETO) and CBF, (PEBP2,)-MYH11 chimaeric proteins are generated by t(8;21) and inv(16) respectively. We analysed gene expression profiles of leukaemic cells by microarray, and selected genes whose expression appeared to be modulated in association with t(8;21) and inv(16). In a pair-wise comparison, 15% of t(8;21)-associated transcripts exhibited high or low expression in inv(16)-AML, and 26% of inv(16)-associated transcripts did so equivalently in t(8;21)-AML. These common elements in gene expression profiles between t(8;21)- and inv(16)-AML probably reflect the situation that AML1-MTG8 and CBF, -MYH11 chimaeric proteins affect a common set of target genes in CBF leukaemic cells. On the other hand, 38% of t(8;21)-associated and 24% of inv(16)-associated transcripts were regulated in t(8;21)- and inv(16)-specific manners. These distinct features of t(8;21)- and inv(16)-associated genes correlate with the bimodular structures of the chimaeric proteins (CBF-related AML1 and CBF, portions, and CBF-unrelated MTG8 and MYH11 portions). [source] Managing the "hollow state": procedural policy instruments and modern governanceCANADIAN PUBLIC ADMINISTRATION/ADMINISTRATION PUBLIQUE DU CANADA, Issue 4 2000Michael Howlett Recent works by Canadian, Dutch, American, British and French scholars have begun to describe a common set of policy instruments contemporary governments now use to indirectly steer social actors towards their preferred policy options. Unlike traditional "substantive" instruments, which directly affect the delivery of goods and services in society, these "procedural" policy instruments are intended to manage state-societal interactions in order to assure general support for government aims and initiatives. Used on an ad hoc basis in the past, these tools have become an essential feature of modern governance. This article advances the study of these procedural policy instruments by developing a taxonomy and outlining the rationale for choosing between particular instrument types. Sommaire: Les gouvernements se trouvent aujourd'hui face à un paradoxe: d'une part, leur pouvoir d'intervention est en principe important au niveau des connais-sances, de I'expertise, des budgets et du personnel; d'autre part, les phénomènes tels que la mondialisation et la démocratisation ont fortement sapé leur capacité d'influer directement sur les résultats sociaux. Des travaux récents d'auteurs canadiens, néer-landais, américains, britanniques et français amorcent la description d'un ensemble commun d'instruments directifs dont se servent actuellement les gouvernements pour orienter indirectement les intervenants sociaux vers les options politiques que les gouvernements préfèrent. À I'encontre des instruments classiques « substantifs » influant directement sur la prestation de biens et services au sein de la société, ces instruments « procéduraux » visent é gkrer l'interaction État-société de manière à ce que les initiatives et objectifs gouvernementaux reçoivent l'appui de tous. Utilisés de manière ponctuelle dans le passé, ces outils sont devenus un éléments essentiel de la gouvemance moderne. Cet article fait progresser l'étude de ces instruments de procédure pour l'élaboration des politiques, en définissant une taxonomie et en pré-cisant les raisons pour lesquelles un type d'instrument particulier serait préférable à un autre. [source] ESE-3, an Ets family transcription factor, is up-regulated in cellular senescenceCANCER SCIENCE, Issue 9 2007Makoto Fujikawa Normal cells irreversibly stop dividing after being exposed to a variety of stresses. This state, called cellular senescence, has recently been demonstrated to act as a tumor-suppressing mechanism in vivo. A common set of features are exhibited by senescent cells, but the molecular mechanism leading to the state is poorly understood. It has been shown that p38, a stress-induced mitogen-activated protein kinase (MAPK), plays a pivotal role in inducing cellular senescence in diverse settings. To better understand the senescence-inducing pathway, microarray analyses of normal human fibroblasts that ectopically activated p38 were performed. It was found that five genes encoding ESE-3, inhibin ,A, RGS5, SSAT and DIO2 were up-regulated in senescent cells induced by RasV12, H2O2 and telomere shortening, but not in quiescent or actively growing cells, suggesting that these genes serve as molecular markers for various types of cellular senescence. The ectopic expression of ESE-3 resulted in retarded growth, up-regulation of p16INK4a but not of p21, and increased levels of SA-,-gal activity. In contrast, RGS5, SSAT and the constitutive active form of the inhibin ,A receptor gene did not induce such senescence phenotypes when ectopically expressed. ESE-3 expression increased the activity of the p16INK4a promoter in a reporter assay, and recombinant ESE-3 protein bound to the Ets-binding sequences present in the promoter. These results suggest that ESE-3 plays a role in the induction of cellular senescence as a downstream molecule of p38. (Cancer Sci 2007; 98: 1468,1475) [source] Computation and analysis of 19F substituent chemical shifts of some bridgehead-substituted polycyclic alkyl fluoridesMAGNETIC RESONANCE IN CHEMISTRY, Issue 7 2003William Adcock Abstract The 19F NMR shieldings for several remotely substituted rigid polycyclic alkyl fluorides with common sets of substituents covering a wide range of electronic effects were calculated using the DFT-GIAO theoretical model. The level of theory, B3LYP/6,311+G(2d,p), was chosen based on trial calculations which gave good agreement with experimental values where known. The optimized geometries were used to obtain various molecular parameters (fluorine natural charges, electron occupancies on fluorine of lone pairs and of the CF bond, and hybridization states) by means of natural bond orbital (NBO) analysis which could help in understanding electronic transmission mechanisms underlying 19F substituent chemical shifts (SCS) in these systems. Linear regression analysis was employed to explore the relationship between the calculated 19F SCS and polar substituent constants and also the NBO derived molecular parameters. The 19F SCS are best described by an electronegativity parameter. The most pertinent molecular parameters appear to be the occupation number of the NBO p-type fluorine lone pair and the occupation number of the CF antibonding orbital. This trend suggests that in these types of rigid saturated systems hyperconjugative interactions play a key role in determining the 19F SCS. Electrostatic field effects appear to be relatively unimportant. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||