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Weak Support (weak + support)
Selected AbstractsRelationship of cranial robusticity to cranial form, geography and climate in Homo sapiensAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 1 2010Karen L. Baab Abstract Variation in cranial robusticity among modern human populations is widely acknowledged but not well-understood. While the use of "robust" cranial traits in hominin systematics and phylogeny suggests that these characters are strongly heritable, this hypothesis has not been tested. Alternatively, cranial robusticity may be a response to differences in diet/mastication or it may be an adaptation to cold, harsh environments. This study quantifies the distribution of cranial robusticity in 14 geographically widespread human populations, and correlates this variation with climatic variables, neutral genetic distances, cranial size, and cranial shape. With the exception of the occipital torus region, all traits were positively correlated with each other, suggesting that they should not be treated as individual characters. While males are more robust than females within each of the populations, among the independent variables (cranial shape, size, climate, and neutral genetic distances), only shape is significantly correlated with inter-population differences in robusticity. Two-block partial least-squares analysis was used to explore the relationship between cranial shape (captured by three-dimensional landmark data) and robusticity across individuals. Weak support was found for the hypothesis that robusticity was related to mastication as the shape associated with greater robusticity was similar to that described for groups that ate harder-to-process diets. Specifically, crania with more prognathic faces, expanded glabellar and occipital regions, and (slightly) longer skulls were more robust than those with rounder vaults and more orthognathic faces. However, groups with more mechanically demanding diets (hunter-gatherers) were not always more robust than groups practicing some form of agriculture. Am J Phys Anthropol, 2010. © 2009 Wiley-Liss, Inc. [source] Developing indicators for measuring Research Capacity Development in primary care organizations: a consensus approach using a nominal group techniqueHEALTH & SOCIAL CARE IN THE COMMUNITY, Issue 3 2009Gill Sarre LCST Abstract Research Capacity Development (RCD) in the National Health Service supports the production of evidence for decision-making in policy and practice. This study aimed to establish a level of consensus on a range of indicators to measure research capacity in primary care organizations. Indicators were developed in a two-stage process using workshops and modified nominal group technique. In 2005, workshops were used to generate possible indicators from a wide range of research active and research-interested people. A theoretical framework of six principles of RCD was used to explore and identify indicators. Data were thematically coded, and a 129-item, 9-point Likert scale questionnaire was developed. A purposive sample of nine experts in developing research capacity in primary care agreed to take part in a nominal group in April 2006. The questionnaire was circulated prior to the meeting, and analysis of the responses formed the basis for structured discussion. Participants were then asked to rescore the questionnaire. Only seven participants were able to take part in the discussion and rescore stages. Data were analysed in two ways: level of relevance attributed to each indicator as a measure of organizational RCD, represented by median responses (medians of 7,9 defined strong support, 4,6 indicated moderate support and 1,3 indicated weak support), and level of consensus reached by the group. Consensus was reached if 85% of the group rated an indicator within the same band. Eighty-nine (68%) indicators were ranked as strongly relevant, and for seventy-three of these indicators, a consensus was reached. The study was successful in generating a set of agreed indicators considered relevant for measuring RCD in primary care organizations. These will form the basis of a pilot tool kit to assist primary care organizations to develop research capacity. Further work will explore the applicability of the indicators in practice. [source] The effect of diet on the expression of lipase genes in the midgut of the lightbrown apple moth (Epiphyas postvittana Walker; Tortricidae)INSECT MOLECULAR BIOLOGY, Issue 1 2010J. T. Christeller Abstract We have identified lipase-like genes from an Epiphyas postvittana larval midgut EST library. Of the 10 pancreatic lipase family genes, six appear to encode active lipases and four encode inactive lipases, based on the presence/absence of essential catalytic residues. The four gastric lipase family genes appear to encode active proteins. Phylogenetic analysis of 54 lepidopteran pancreatic lipase proteins resolved the clade into five groups of midgut origin and a sixth of non-midgut lipases. The inactive proteins formed two separate groups with highly conserved mutations. The lepidopteran midgut lipases formed a ninth subfamily of pancreatic lipases. Eighteen insect and human gastric lipases were analysed phylogenetically with only very weak support for any groupings. Gene expression was measured in the larval midgut following feeding on five artificial diets and on apple leaves. The artificial diets contained different levels of triacylglycerol, linoleic acid and cholesterol. Significant changes in gene expression (more than 100-fold for active pancreatic lipases) were observed. All the inactive lipases were also highly expressed. The gastric lipase genes were expressed at lower levels and suppressed in larvae feeding on leaves. Together, protein motif analysis and the gene expression data suggest that, in phytophagous lepidopteran larvae, the pancreatic lipases may function in vivo as galactolipases and phospholipases whereas the gastric lipases may function as triacylglycerol hydrolases. [source] Explaining the global pattern of protected area coverage: relative importance of vertebrate biodiversity, human activities and agricultural suitabilityJOURNAL OF BIOGEOGRAPHY, Issue 8 2008Colby Loucks Abstract Aim, Twelve per cent of the Earth's terrestrial surface is covered by protected areas, but neither these areas nor the biodiversity they contain are evenly distributed spatially. To guide future establishment of protected areas, it is important to understand the factors that have shaped the spatial arrangement of the current protected area system. We used an information-theoretic approach to assess the ability of vertebrate biodiversity measures, resource consumption and agricultural potential to explain the global coverage pattern of protected areas. Location, Global. Methods, For each of 762 World Wildlife Fund terrestrial ecoregions of the world, we measured protected area coverage, resource consumption, terrestrial vertebrate species richness, number of endemic species, number of threatened species, net primary production, elevation and topographic heterogeneity. We combined these variables into 39 a priori models to describe protected area coverage at the global scale, and for six biogeographical realms. Using the Akaike information criterion and Akaike weights, we identified the relative importance and influence of each variable in describing protected area coverage. Results, Globally, the number of endemic species was the best variable describing protected area coverage, followed by the number of threatened species. Species richness and resource consumption were of moderate importance and agricultural potential had weak support for describing protected area coverage at a global scale. Yet, the relative importance of these factors varied among biogeographical realms. Measures of vertebrate biodiversity (species richness, endemism and threatened species) were among the most important variables in all realms, except the Indo-Malayan, but had a wide range of relative importance and influence. Resource consumption was inversely related to protected area coverage across all but one realm (the Palearctic), most strongly in the Nearctic realm. Agricultural potential, despite having little support in describing protected area coverage globally, was strongly and positively related to protection in the Palearctic and Neotropical realms, as well as in the Indo-Malayan realm. The Afrotropical, Indo-Malayan and Australasian realms showed no clear, strong relationships between protected area coverage and the independent variables. Main conclusions, Globally, the existing protected area network is more strongly related to biodiversity measures than to patterns of resource consumption or agricultural potential. However, the relative importance of these factors varies widely among the world's biogeographical realms. Understanding the biases of the current protected area system may help to correct for them as future protected areas are added to the global network. [source] Choice of Accounting Method for Valuation of Investment Securities: Evidence from Hong Kong FirmsJOURNAL OF INTERNATIONAL FINANCIAL MANAGEMENT & ACCOUNTING, Issue 2 2003Bikki Jaggi This study examines whether Hong Kong managers choose "benchmark" or "alternative" valuation method for investment securities, after the Hong Kong SSAP 24 became effective starting with fiscal-year ending December 31, 1999. Tests are conducted on a sample of 292 firms, out of which 155 Hong Kong firms reported unrealized gains and losses and 128 firms that did not report holding gains/losses, but reported investment securities. The findings indicate that firms with strong relative performance, i.e. current year's EPS higher than that of the last year, chose the alternative valuation method when the investment securities had holding gains and recognized the unrealized holding gains in the equity section of the balance sheet. This finding is consistent with the Cookie Jar hypothesis because these holding gains would be used in the income statement in future periods, when needed. With regard to firms with strong relative performance and holding losses, the findings indicate that the benchmark valuation was used. The losses were reported in the income statement to the extent that they did not reduce the EPS below that of the last year. This finding is consistent with the Income Smoothing Hypothesis, because the use of benchmark valuation reduced EPS of the current year to bring it in line with that of the last year. Evidence on firms with weak economic performance and holding gains or losses provided weak support to the Income Smoothing Hypothesis and Big Bath Hypothesis. Additionally, the results indicate that the firms with high debt-equity ratio preferred the benchmark method and recorded securities at cost. This treatment provided managers with an opportunity to liquidate or reclassify the securities in future periods and use the accrued gains, when needed. The findings are inconclusive with regard to the impact of bonus plan on the choice of valuation method. [source] Neuropsychological Deficits in Sober Alcoholics: Influences of Chronicity and Recent Alcohol ConsumptionALCOHOLISM, Issue 2 2000William W. Beatty Background: The relationships between severity of neuropsychological (NP) deficits and quantity and duration of alcoholic drinking remain controversial. Eckardt et al. (1998) proposed that NP deficits can be observed only if chronicity of alcohol abuse equals or exceeds 10 years. In this study we tested the hypothesis of Eckardt et al. and reexamined the relationship of NP performance and alcohol consumption. Methods: One hundred sixty-two alcoholics and 165 controls completed a NP test battery at least 3 weeks after the alcoholics attained sobriety. Chronicity varied from 4 to 9 years for 55 alcoholics and from 10 to 33 years for the remaining 107. Results: Compared to controls, both groups of alcoholics were impaired on the Shipley Vocabulary and Abstraction tests and on two versions of the Digit Symbol test, but there was no difference between the two alcoholic groups on any measure. Regression analyses that controlled for age and education showed that chronicity predicted less than 0.5% of the variance on NP measures. By contrast, a measure of recent alcohol consumption, the Quantity-Frequency Index, contributed significantly (approximately 5% of the variance) to the prediction of alcoholics'NP performance. Conclusions: These data provide weak support for a dose effect relationship between degree of NP impairment and level of alcoholic drinking in the past 6 months but no evidence for an influence of chronicity. [source] The genetic architecture of disease resistance in plants and the maintenance of recombination by parasitesMOLECULAR ECOLOGY, Issue 1 2001Paula X. Kover Abstract Parasites represent strong selection on host populations because they are ubiquitous and can drastically reduce host fitness. It has been hypothesized that parasite selection could explain the widespread occurrence of recombination because it is a coevolving force that favours new genetic combinations in the host. A review of deterministic models for the maintenance of recombination reveals that for recombination to be favoured, multiple genes that interact with each other must be under selection. To evaluate whether parasite selection can explain the maintenance of recombination, we review 85 studies that investigated the genetic architecture of plant disease resistance and discuss whether they conform to the requirements that emerge from theoretical models. General characteristics of disease resistance in plants and problems in evaluating resistance experimentally are also discussed. We found strong evidence that disease resistance in plants is determined by multiple loci. Furthermore, in most cases where loci were tested for interactions, epistasis between loci that affect resistance was found. However, we found weak support for the idea that specific allelic combinations determine resistance to different host genotypes and there was little data on whether epistasis between resistance genes is negative or positive. Thus, the current data indicate that it is possible that parasite selection can favour recombination, but more studies in natural populations that specifically address the nature of the interactions between resistance genes are necessary. The data summarized here suggest that disease resistance is a complex trait and that environmental effects and fitness trade-offs should be considered in future models of the coevolutionary dynamics of host and parasites. [source] The Evolutionary Forms of the Religious Life: A Cross-Cultural, Quantitative AnalysisAMERICAN ANTHROPOLOGIST, Issue 4 2008STEPHEN K. SANDERSON ABSTRACT, Previous cross-cultural studies of religion's evolution that employed Swanson's High Gods measure are plagued by methodological difficulties, especially the lack of proper statistical controls. Here, we attempted to rectify this, using the Standard Cross-Cultural Sample to test five hypotheses employing multivariate statistical techniques. Results provided weak support for Swanson's Sovereign Groups hypothesis concerning High Gods and also limited support for a previously unexplored factor: writing and record keeping. In phase two of the study, we introduced a new measure, the Stage of Religious Evolution, based on Anthony Wallace's typology. When this new dependent variable was substituted for High Gods, much stronger results were obtained. The best predictors of Stage of Religious Evolution were mode of subsistence economy, writing and record keeping, and total population size. These findings allowed us to construct a new evolutionary interpretation of the development of different modes of religious life. [source] What Fraction of a Capital Investment is Sunk Costs?THE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 3 2000Marcus Asplund To what extent are capital investments sunk costs? This question is addressed by examining the salvage values of discarded metalworking machinery. Even though such assets are expected to be non-specific, many discarded assets are scrapped rather than sold on second-hand markets. Econometric results suggest that firms can only expect to get back 20,50 percent of the initial price of a ,new' machine once it is installed. The results also indicate differences in value-age profiles across firms, but provide only weak support for the hypothesis that salvage values are particularly low during recessions. [source] DEPOSITOR DISCIPLINE, REGULATORY CONTROL, AND A BANKING CRISIS: A STUDY OF INDIAN URBAN COOPERATIVE BANKSANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 4 2007Niranjan CHIPALKATTI ABSTRACT,:,Urban Cooperative banks in India (UCBs) play an important role in mobilizing resources from lower and middle-income groups and in providing direct finance to small entrepreneurs and traders. Motivated by previous empirical work on depositor disciplining behaviour, this paper examines whether depositors punish weak UCBs by withdrawing deposits during and after a banking crisis. In addition, the paper investigates the impact of tightened prudential standards imposed by the Indian central bank (RBI) on the ratio of investments to loan assets and on the rate of growth of loans. Our sample of 45 UCBs is partitioned into strong and weak banks and subjected to econometric testing. Our analysis reveals that a banking crisis is associated with a contraction in deposits across the sample. However, weak banks appear to be disciplined by depositors during election years. We also find weak support for the contention that banks reduced loans when faced with intensified regulatory scrutiny in the aftermath of a crisis. [source] Does disturbance, competition or resource limitation underlie Hieracium lepidulum invasion in New Zealand?AUSTRAL ECOLOGY, Issue 3 2010Mechanisms of establishment, functional differentiation among invasive, native species, persistence Abstract The processes underlying plant invasions have been the subject of much ecological research. Understanding mechanisms of plant invasions are difficult to elucidate from observations, yet are crucial for ecological management of invasions. Hieracium lepidulum, an asteraceous invader in New Zealand, is a species for which several explanatory mechanisms can be raised. Alternative mechanisms, including competitive dominance, disturbance of resident vegetation allowing competitive release or nutrient resource limitation reducing competition with the invader are raised to explain invasion. We tested these hypotheses in two field experiments which manipulated competitive, disturbance and nutrient environments in pre-invasion and post-invasion vegetation. H. lepidulum and resident responses to environmental treatments were measured to allow interpretation of underlying mechanisms of establishment and persistence. We found that H. lepidulum differed in functional response profile from native species. We also found that other exotic invaders at the sites were functionally different to H. lepidulum in their responses. These data support the hypothesis that different invaders use different invasion mechanisms from one another. These data also suggest that functional differentiation between invaders and native resident vegetation may be an important contributing factor allowing invasion. H. lepidulum appeared to have little direct competitive effect on post-invasion vegetation, suggesting that competition was not a dominant mechanism maintaining its persistence. There was weak support for disturbance allowing initial establishment of H. lepidulum in pre-invasion vegetation, but disturbance did not lead to invader dominance. Strong support for nutrient limitation of resident species was provided by the rapid competitive responses with added nutrients despite presence of H. lepidulum. Rapid competitive suppression of H. lepidulum once nutrient limitation was alleviated suggests that nutrient limitation may be an important process allowing the invader to dominate. Possible roles of historical site degradation and/or invader-induced soil chemical/microbial changes in nutrient availability are discussed. 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