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Ample Opportunity (ample + opportunity)
Selected AbstractsMultistage designs in the genomic era: Providing balance in complex disease studiesGENETIC EPIDEMIOLOGY, Issue S1 2007Marie-Pierre Dubé Abstract In this summary paper, we describe the contributions included in the Multistage Design group (Group 14) at the Genetic Analysis Workshop 15, which was held during November 12,14, 2006. Our group contrasted and compared different approaches to reducing complexity in a genetic study through implementation of staged designs. Most groups used the simulated dataset (problem 3), which provided ample opportunities for evaluating various staged designs. A wide range of multistage designs that targeted different aspects of complexity were explored. We categorized these approaches as reducing phenotypic complexity, model complexity, analytic complexity or genetic complexity. In general we learned that: (1) when staged designs are carefully planned and implemented, the power loss compared to a single-stage analysis can be minimized and study cost is greatly reduced; (2) a joint analysis of the results from each stage is generally more powerful than treating the second stage as a replication analysis. Genet. Epidemiol. 31 (Suppl. 1):S118,S123, 2007. © 2007 Wiley-Liss, Inc. [source] Front Cover (Phys. Status Solidi B 6/2010)PHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 6 2010M. Grundmann A Special Section in this issue (pp. 1257,1392) is devoted to research conducted in the research group FOR 522 headed by Prof. Marius Grundmann (University of Leipzig, Germany). The group designed and realized various nanostructures with three-dimensionally controlled geometry. Nanowires based on III,V and II,VI semiconductors as well as thermoelectric materials have been investigated. Curved structures , screws, spirals, tubes, and scrolls , have been fabricated using internal strains and specially designed growth processes. Out of the various explored structures promising routes for the study of fundamental effects have been identified which provide ample opportunities for further research. [source] Speciation on the Azores islands: congruent patterns in shell morphology, genital anatomy, and molecular markers in endemic land snails (Gastropoda, Leptaxinae)BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009KURT JORDAENS Morphological data, in combination with molecular data, may provide invaluable insights into speciation processes on archipelagos. Land snails offer ample opportunities to evalutate adaptive and non-adaptive speciation scenarios. However, studies investigating processes of differentiation and speciation on the Azores are scarce. The present study comprises a morphometrical analysis of shell and genital characters in a group of Azorean land snails (Pulmonata, Leptaxinae). Geographical isolation appears to be an important mechanism underlying morphological and molecular differentiation in the Azorean Leptaxini, instead of adaptive radiation through ecological differentiation. Nevertheless, we could not exclude the occurrence of ecological speciation on the oldest island (Santa Maria) where two species that markedly differ in shell-shape co-occur. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 166,176. [source] Discovery and Design of Novel HSP90 Inhibitors Using Multiple Fragment-based Design StrategiesCHEMICAL BIOLOGY & DRUG DESIGN, Issue 1 2007Jeffrey R. Huth The molecular chaperone HSP90 has been shown to facilitate cancer cell survival by stabilizing key proteins responsible for a malignant phenotype. We report here the results of parallel fragment-based drug design approaches in the design of novel HSP90 inhibitors. Initial aminopyrimidine leads were elaborated using high-throughput organic synthesis to yield nanomolar inhibitors of the enzyme. Second site leads were also identified which bound to HSP90 in two distinct conformations, an ,open' and ,closed' form. Intriguingly, linked fragment approaches targeting both of these conformations were successful in producing novel, micromolar inhibitors. Overall, this study shows that, with only a few fragment hits, multiple lead series can be generated for HSP90 due to the inherent flexibility of the active site. Thus, ample opportunities exist to use these lead series in the development of clinically useful HSP90 inhibitors for the treatment of cancers. [source] MUSEUM SPECIMENS AND PHYLOGENIES ELUCIDATE ECOLOGY'S ROLE IN COEVOLUTIONARY ASSOCIATIONS BETWEEN MITES AND THEIR BEE HOSTSEVOLUTION, Issue 6 2007Pavel B. Klimov Coevolutionary associations between hosts and symbionts (or parasites) are often reflected in correlated patterns of divergence as a consequence of limitations on dispersal and establishment on new hosts. Here we show that a phylogenetic correlation is observed between chaetodactylid mites and their hosts, the long-tongued bees; however, this association manifests itself in an atypical fashion. Recently derived mites tend to be associated with basal bee lineages, and vice versa, ruling out a process of cospeciation, and the existence of mites on multiple hosts also suggests ample opportunity for host shifts. An extensive survey of museum collections reveals a pattern of infrequent host shifts at a higher taxonomic level, and yet, frequent shifts at a lower level, which suggests that ecological constraints structure the coevolutionary history of the mites and bees. Certain bee traits, particularly aspects of their nesting behavior, provide a highly predictive framework for the observed pattern of host use, with 82.1% of taxa correctly classified. Thus, the museum survey and phylogenetic analyses provide a unique window into the central role ecology plays in this coevolutionary association. This role is apparent from two different perspectives,as (a) a constraining force evident in the historical processes underlying the significant correlation between the mite and bee phylogenies, as well as (b) by the highly nonrandom composition of bee taxa that serve as hosts to chaetodactylid mites. [source] Levels of inbreeding depression over seven generations of selfing in the androdioecious clam shrimp, Eulimnadia texanaJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 3 2004S. C. Weeks Abstract Androdioecy (mixtures of males and hermaphrodites) is a rare mating system in both plants and animals. Theory suggests that high levels of inbreeding depression can maintain males in androdioecious populations if hermaphrodites commonly self-fertilize. However, if inbreeding depression (,) can be ,purged' from selfing populations, maintaining males is more difficult. In the androdioecious clam shrimp, Eulimnadia texana, , is estimated to be as high as 0.7. Previous work suggests that this high level is maintained in the face of high levels of inbreeding due to an associative overdominance of fitness-related loci with the sex-determining locus. Such associative overdominance would make purging of inbreeding depression difficult to impossible. The current experiment was designed to determine if , can be purged in these shrimp by tracking fitness across seven generations in selfing and outcrossing treatments. Evidence of purging was found in one of four populations, but the remaining populations demonstrated a consistent pattern of , across generations. Although the experimental design allowed ample opportunity for purging, the majority of populations were unable to purge their genetic load. Therefore, , in this species is likely due to associative overdominance caused by deleterious recessive alleles linked to the sex determining locus. [source] A possible CD1a Langerhans cell,mast cell interaction in chronic hyperplastic candidosisJOURNAL OF ORAL PATHOLOGY & MEDICINE, Issue 6 2007Ahmed Ali Aims:, T lymphocyte,antigen-presenting cell (APC) interaction plays a central role in T lymphocyte activation and APC maturation. We therefore studied the CD1a-positive Langerhans cells with respect to receptor activator of nuclear factor kappa B ligand (RANKL)-positive cells in chronic hyperplastic candidosis (CHC). Materials and methods:, Tissue sections of CHC were compared with leukoplakia and healthy oral mucosa using RANKL and CD1a monoclonal antibodies in an avidin,biotin peroxidase complex protocol. Two different antigen-retrieval protocols, pepsin preincubation and Tris,EDTA heat treatment, were used. Results:, CD1a-positive Langerhans cells were in healthy and leukoplakia epithelium found in the middle layer, but in CHC in all layers of the epithelium, at the basement membrane and as mononuclear round cells in the lamina propria. Use of pepsin digestion enabled studies of mast cells and their activation in the form of degranulation of RANKL. Conclusions:, The numerical, morphological and topographical versatility of the CD1a-positive Langerhans cells in CHC can be clarified by dendritic cell (DC) recruitment into the epithelium. RANK-positive and RANKL-sensitive DCs have ample opportunity to interact with local T lymphocytes. Use of an optimized antigen-retrieval protocol enabled demonstration of an active engagement (degranulation) of mast cells, which represent a rapidly available source of soluble RANKL. [source] The Role of Process Evaluation in the Training of Facilitators for an Adolescent Health Education ProgramJOURNAL OF SCHOOL HEALTH, Issue 4 2000Deborah Helitzer ABSTRACT: This article reports on the process evaluation of the training of facilitators for the Adolescent Social Action Program, a health education program in Albuquerque, New Mexico that trained college students and adult volunteers to work with middle school students. From the process evaluation data collected throughout a four-year period (1995,1998), data relevant to training are described: facilitator characteristics, facilitator training, curriculum implementation, and use of the program's model designed to promote critical thinking and dialogue. Results indicated that, though most facilitators reported the training was sufficient to enable them to implement the curriculum, they did not completely do so, especially as groups reached their final sessions. Facilitators covered the core curriculum content, but often failed to follow through with the more abstract activities. The need to perform and report the process evaluation in time to provide ample opportunity for trainers and curriculum designers to make appropriate adjustments is discussed. [source] Policies of Extinction: The Life and Death of Canada's Endangered Species LegislationPOLICY STUDIES JOURNAL, Issue 1 2000Raymond A. Rogers This article examines the attempt by the Canadian Federal Government to pass endangered species legislation (1995). It focuses on the constraints which confront the creation of environmental policy in Canada and identifies jurisdictional overlap and stakeholder conflict as the prime source of difficulties which confronted the Federal Government as it moved through the policy process for creating endangered species legislation. The wide-ranging consultation process leading up to the creation of the legislation provided ample opportunity for powerful interests to undermine the protection of endangered species. The article concludes with a discussion of endangered species legislation as an example of the failure of the "crisis management" approach to conservation and sustainability. [source] Sexual limitations in people living with Parkinson's diseaseAUSTRALASIAN JOURNAL ON AGEING, Issue 4 2005Sarah Mott Objectives:,To explore disease sequelae and usage of support services in people living with Parkinson's disease (PD). Methods:,A 31-item survey was administered to a convenience sample of people with PD recruited through Parkinson's NSW Inc. and its support groups. Results:,Four hundred and forty-four responses were received. Sexual limitations were reported by 73.5% of people with PD. Additionally, respondents indicated that health professionals did not necessarily understand what it is like to live with the disease. Conclusions:,Movement problems are most often presented as the major sequelae of PD. This study shows that for a large proportion of sufferers, sexual limitations are an issue. Additionally, it is important for health professionals to provide ample opportunity for the discussion of these difficulties. [source] Acoustical Properties of Binary Mixtures of Heptane with Ethyl Acetate or Butyl AcetateCHINESE JOURNAL OF CHEMISTRY, Issue 3 2010Divya Shukla Abstract Mixed solvents rather than single pure liquids are of utmost practical importance in chemical and industrial processes as they provide an ample opportunity for the continuous adjustment of desired properties of the medium. Therefore, ultrasonic velocity (u) and density (,) were measured for the binary mixtures formed by heptane with ethyl acetate or butyl acetate at temperatures 293, 298 and 303 K over the entire composition range. Deviation in ultrasonic velocity (,u), deviation in isentropic compressibility (,,s), and excess intermolecular free length (LEf) have been evaluated using the ultrasonic velocity data and the computed results were fitted to the Redlich-Kister polynomial equation. The values of ,u, ,,s and LEf were plotted against the molar fraction of heptane. The observed positive and negative values of excess parameters were discussed in terms of molecular interaction between the components of the mixtures. Experimental values of ultrasonic velocity and density were compared with the results obtained by theoretical estimation procedures. The results were discussed in terms of average absolute deviation (AAD). [source] | |||||||||||||