Little Support (little + support)

Distribution by Scientific Domains


Selected Abstracts


THE NARROWING GENDER GAP IN ARRESTS: ASSESSING COMPETING EXPLANATIONS USING SELF-REPORT, TRAFFIC FATALITY, AND OFFICIAL DATA ON DRUNK DRIVING, 1980,2004,

CRIMINOLOGY, Issue 3 2008
JENNIFER SCHWARTZ
We evaluate two alternative explanations for the converging gender gap in arrest,changes in women's behavior versus changes in mechanisms of social control. Using the offense of drunk driving and three methodologically diverse data sets, we explore trends in the DUI gender gap. We probe for change across various age groups and across measures tapping DUI prevalence and chronicity. Augmented Dickey-Fuller time-series techniques are used to assess changes in the gender gap and levels of drunk driving from 1980 to 2004. Analyses show women of all ages making arrest gains on men,a converging gender gap. In contrast, self-report and traffic data indicate little or no systematic change in the DUI gender gap. Findings support the conclusion that mechanisms of social control have shifted to target female offending patterns disproportionately. Little support exists for the contention that increased strain and liberalized gender roles have altered the gender gap or female drunk-driving patterns. [source]


Social capital, age and religiosity in people who are lonely

JOURNAL OF CLINICAL NURSING, Issue 3 2006
William Lauder PhD
Aims and objectives., The aims of the study were to (i) investigate age and loneliness, (ii) investigate the association between religiosity and loneliness, and (iii) and explore the relationship between social capital and loneliness. Background., Loneliness is the subjective experience of social isolation and is a risk factor for a wide range of health problems including heart disease and depression. Poor self-rated health, domestic violence and poor economic conditions are associated with greater loneliness. Design., The study was a cross-sectional survey of a random sample of adults aged 18 years and over. Methods., A random sample of 1289 subjects was interviewed by computer-assisted telephone interviewing. This interview included the Loneliness Scale and items from the Social Capital Module of the General Household Survey. Findings., Loneliness is more common in men and people without strong religious beliefs. An income-loneliness gradient is evident. Little support was found for the association between social capital and loneliness. Conclusion., The prevalence of loneliness is relatively stable in this population. Loneliness is linked to income and unemployment and as such pathways between socio-economic factors, loneliness and health need to guide interventions and future research. Relevance to clinical practice., Loneliness is linked to a range of social and economic factors. Current Health Visiting practice recognizes the importance of tackling the effects of poverty and social deprivation and places community building at the core of much Health Visiting practice. This broad community level approach can usefully transfer into all community nursing and health promotion activity. [source]


THE DEMAND FOR BEER, WINE AND SPIRITS: A SURVEY OF THE LITERATURE

JOURNAL OF ECONOMIC SURVEYS, Issue 3 2010
James Fogarty
Abstract The demand for alcohol literature is vast and much conflicting information about the nature of the demand for alcoholic beverages has been published. This paper presents a survey of the literature, and then uses the technique of meta-regression analysis to establish insights into the nature of the demand for beer, wine and spirits. Unlike previous meta-studies of the demand for alcoholic beverages this study adjusts for the precision of each elasticity estimate. The analysis presented suggests reported elasticity estimates will be influenced by such factors as estimation technique, data frequency and time period under consideration. With respect to time, the findings suggest that the demand for alcoholic beverages has become less inelastic since the mid-1950s and that the income elasticity has been falling since the mid-1960s. The analysis also found support for the idea that alcohol as a commodity group is a necessity, and that consumers respond to price discounting with inventory behaviour rather than true substitution behaviour. Little support is found for the idea that the demand for alcoholic beverages varies fundamentally across most countries, although wine may be an exception. [source]


Familial Factors Associated With the Use of Multiple Child-Care Arrangements

JOURNAL OF MARRIAGE AND FAMILY, Issue 2 2008
Taryn W. Morrissey
This study examined the use of multiple, concurrent, nonparental child-care arrangements among children under 5 with employed mothers in the NICHD Study of Early Child Care and Youth Development (N= 759). Older children, those primarily cared for in informal child care, those living in cohabitating or single-parent households, and those whose mothers were employed for 40 or fewer hours per week were likely to be in multiple arrangements. Higher quality primary child-care and lower maternal satisfaction with primary care predicted the subsequent use of multiple arrangements. Little support for income differences in selection into multiple arrangements was found. Findings highlight the importance of child-care characteristics and structure in child-care choice. Policy implications are discussed. [source]


How is Well-Being Related to Membership in New Religious Movements?

APPLIED PSYCHOLOGY, Issue 2 2010
An Application of Person, Environment Fit Theory
Ongoing public discussion about the consequences of membership in new religious movements (NRMs) and the lack of studies concerning the relationship between the fit of the person with his or her NRM and well-being together call for a theoretically based investigation of the phenomenon. Hence, this German study on new members of three NRMs applied person,environment fit theory to investigate whether the fit between persons' needs for autonomy and relatedness, on the one hand, and the commensurate supplies of the groups, on the other, are related to well-being and mental health. The regression model following Edwards (1994) predicted satisfaction with religious affiliation, mental health, and depression, but not life satisfaction and anxiety. Results indicate that, for autonomy and relatedness, well-being measures tend to decrease as supplies exceed needs. Little support was found for a moderator effect of centrality of religiosity. Overall, findings encourage the application of person,environment fit theory to the study of membership in (new) religious groups and call for further research. L'actuel débat public sur les conséquences de l'adhésion à un nouveau mouvement religieux et l'absence d'études sur la relation entre l'adaptation de la personne à son groupe et son bien-être nécessitent une investigation fondée théoriquement. D'où cette recherche allemande sur les nouveaux membres de trois de ces mouvements: on est parti de la théorie de l'adéquation personne-environnement pour savoir si l'ajustement entre les besoins personnels d'autonomie et autres besoins analogues d'une part, et les réponses du groupe dans ce domaine d'autre part, étaient reliés au bien-être et à la santé mentale. Le modèle de régression d'Edwards (1994) porte sur la satisfaction concernant l'engagement religieux, la santé mentale et la dépression, mais pas sur l'anxiété et la satisfaction liée à l'existence. Les résultats indiquent que, pour ce qui est de l'autonomie et ce qui en dépend, les mesures relatives au bien-être ont tendance à décroître à mesure que l'offre excède les attentes. L'effet modérateur de la centralité de la religiosité n'a pas vraiment été confirmé. Globalement, ce que l'on a obtenu est en faveur de l'application de la théorie de l'ajustement personne-environnement à l'étude de l'adhésion à de (nouveaux) groupes religieux et incite à développer d'autres recherches. [source]


Disease, deficit or denial?

ACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2005
Models of poor insight in psychosis
Objective:, To examine the evidence for the three kinds of aetiological model that dominate the current literature on poor insight in psychosis: clinical models, the neuropsychological model, and the psychological denial model. Method:, Studies pertaining to one or more of these aetiological models were identified, reviewed and critically evaluated. Results:, There is little support for clinical models, partly because they lack testable hypotheses. Several studies reveal a positive relationship between insight and executive function, which may be related to frontal lobe dysfunction. However, the extent to which this relationship is specific and independent of general cognitive impairment remains unclear. There is tentative evidence to support the psychological denial model. Recent data combining the latter two approaches suggest that multiple factors contribute to poor insight. Conclusion:, Integration of different aetiological models is necessary for a fuller understanding of insight in psychosis. Future research should assess multiple aetiological mechanisms in single investigations. [source]


Drug prevention programmes for young people: where have we been and where should we be going?

ADDICTION, Issue 10 2010
Richard Midford
ABSTRACT Aim Substance use by young people has long been a concern of western society, but opinion is mixed as to which prevention approach offers the greatest benefit, and whether indeed there is any benefit at all. This paper reviews the nature of prevention programmes, the research evidence that underpins these programmes and the prevention objectives against which effectiveness is measured. The aim of this is to create better understanding of the elements that maximize programme effectiveness, what can be achieved by prevention programmes and how programmes can be improved. Findings There is a range of prevention approaches for which there is evidence of effectiveness. Some are classroom-based; some focus upon parenting; some have substantial whole-of-school and community elements; and some target risk and protective factors in early childhood. All, however, are based substantially on the social influence model. In an attempt to improve practice lists of effective programmes have been developed, but there are concerns about the science behind selection. On balance, there is consistent evidence that social influence prevention programmes do have a small, positive effect on drug use, but this then raises the question as to whether harm, rather than use, would be the more worthwhile target for prevention. Prevention that seeks to reduce harm has been demonstrably effective, but has found little support in some jurisdictions. Conclusion Research has created a progressively better understanding of how to optimize programme effectiveness and what can be achieved realistically by even the most effective programmes. However, further research is required to identify which, if any, particular approach offers greater promise. The effectiveness of harm reduction should be compared with more traditional abstinence and the additional effects of whole of school, parent and community elements need to be measured more accurately. Contemporary social influence prevention programmes are flawed, but the approach is still the best way of influencing drug use behaviour in young people as a whole. Evidence-based refinement is the best option for greater benefit. [source]


Alliance-Driven Governance: Applying a Global Commodity Chains Approach to the U.K. Biotechnology Industry

ECONOMIC GEOGRAPHY, Issue 1 2008
Kean Birch
Abstract As the economy has globalized, it has also regionalized, which has led to the integration of different spaces across different scales. A number of theories contend that the endogenous assets of these locations provide them with the means to compete in this globalizing economy, especially in relation to knowledge-based sectors like biotechnology. Among these theories, the cluster concept stands out. However, there is little support for the arguments that local linkages are the central contributors to innovation. Extralocal linkages have also been highlighted, suggesting that other theories that account for these linkages may prove useful in the discussion of knowledge-based sectors, in general, and biotechnology, in particular. One such theory is the concept of global commodity chains, which explicitly concerns the interconnections within and across different geographic scales. As yet it has seldom been applied to the biotechnology industry. This article uses the approach to explore the U.K. biotechnology industry. [source]


Cognitive,behavioral treatment for alcohol dependence: a review of evidence for its hypothesized mechanisms of action

ADDICTION, Issue 10 2000
Jon Morgenstern
Objective. This review examined support for the hypothesis that cognitive-behavioral treatment (CBT) for alcohol dependence works through increasing cognitive and behavioral coping skills. Method. Ten studies were identified that examined the hypothesized mechanisms of action of CBT. These studies involved random assignment (or its near equivalent) of participants to CBT and at least one comparison condition. Results. Although numerous analyses of the possible causal links have been conducted to evaluate whether CBT works through increasing coping, the results indicate little support for the hypothesized mechanisms of action of CBT. Conclusions. Research has not yet established why CBT is an effective treatment for alcohol dependence. Negative findings may reflect methodological flaws of prior studies. Alternatively, findings may indicate one or more conceptual assumptions underlying CBT require revision. [source]


Role of biohydrogenation intermediates in milk fat depression

EUROPEAN JOURNAL OF LIPID SCIENCE AND TECHNOLOGY, Issue 8 2007
Kevin J. Shingfield
Abstract Fat is the most variable constituent in milk and is reduced on low-fiber/high-concentrate diets or on rations containing lipid supplements rich in polyunsaturated fatty acids. The biohydrogenation theory attributes the causal mechanism underlying diet-induced milk fat depression (MFD) to changes in ruminal lipid metabolism leading to increased formation of specific biohydrogenation intermediates that exert anti-lipogenic effects. Trans -10, cis -12 conjugated linoleic acid (CLA) is the only intermediate shown unequivocally to inhibit milk fat synthesis. However, increases in ruminal trans -10, cis -12 CLA formation do not provide a universal explanation for the reductions in milk fat during diet-induced MFD, suggesting that other biohydrogenation intermediates may also be involved. Post-ruminal infusion experiments have provided tentative evidence that cis -10, trans -12 CLA and trans -9, cis -11 CLA also exert anti-lipogenic effects. Diet-induced MFD is consistently associated with an increase in milk fat trans -10 18:1 concentrations, but recent direct evidence offers little support for a role of this intermediate in the regulation of milk fat synthesis. Further research is required to characterize the structure and function of other biohydrogenation intermediates, as well as considering the contribution of more global changes in ruminal lipid metabolism to provide a more universal explanation of diet-induced MFD. [source]


Growing supranational identities in a globalising world?

EUROPEAN JOURNAL OF POLITICAL RESEARCH, Issue 5 2008
A multilevel analysis of the World Values Surveys
Using the World Values Surveys (WVS), this article shows that there is a global pattern in public attitudes toward supranational identity: the younger the respondent, the more supranational. Yet a life-cycle effect, as opposed to a generational one, underlies this pattern. A multilevel analysis confirms this age effect on supranational identification in 43 countries covered in the recent wave of the WVS, but provides little support for the idea that a country's integration into the global economy and world society promotes supranational attachments among mass publics, especially youths. Regional integration and globalisation appear either complementary or contradictory to this identity shift, depending upon how ordinary citizens perceive their country's involvement in the processes of regional integration and globalisation, respectively. [source]


THE LOCUS OF EVOLUTION: EVO DEVO AND THE GENETICS OF ADAPTATION

EVOLUTION, Issue 5 2007
Hopi E. Hoekstra
An important tenet of evolutionary developmental biology ("evo devo") is that adaptive mutations affecting morphology are more likely to occur in the cis -regulatory regions than in the protein-coding regions of genes. This argument rests on two claims: (1) the modular nature of cis -regulatory elements largely frees them from deleterious pleiotropic effects, and (2) a growing body of empirical evidence appears to support the predominant role of gene regulatory change in adaptation, especially morphological adaptation. Here we discuss and critique these assertions. We first show that there is no theoretical or empirical basis for the evo devo contention that adaptations involving morphology evolve by genetic mechanisms different from those involving physiology and other traits. In addition, some forms of protein evolution can avoid the negative consequences of pleiotropy, most notably via gene duplication. In light of evo devo claims, we then examine the substantial data on the genetic basis of adaptation from both genome-wide surveys and single-locus studies. Genomic studies lend little support to the cis -regulatory theory: many of these have detected adaptation in protein-coding regions, including transcription factors, whereas few have examined regulatory regions. Turning to single-locus studies, we note that the most widely cited examples of adaptive cis -regulatory mutations focus on trait loss rather than gain, and none have yet pinpointed an evolved regulatory site. In contrast, there are many studies that have both identified structural mutations and functionally verified their contribution to adaptation and speciation. Neither the theoretical arguments nor the data from nature, then, support the claim for a predominance of cis -regulatory mutations in evolution. Although this claim may be true, it is at best premature. Adaptation and speciation probably proceed through a combination of cis -regulatory and structural mutations, with a substantial contribution of the latter. [source]


Interspecific relationships among growth, mortality and xylem traits of woody species from New Zealand

FUNCTIONAL ECOLOGY, Issue 2 2010
Sabrina E. Russo
Summary 1.,Wood density is considered a key functional trait influencing the growth and survival of woody plants and has been shown to be related to a slow,fast rate-of-living continuum. Wood density is, however, an emergent trait arising from several vascular properties of wood, including the diameter and frequency of xylem conduits. 2.,We aimed to test the hypotheses that there is a set of inter-related trade-offs linked to the different functions of wood, that these trade-offs have direct consequences for tree growth and survival and that these trade-offs underlie the observed correlations between wood density and demographic rates. We evaluated the covariation between xylem anatomical traits among woody species of New Zealand and whether that covariation had the potential to constrain variation in wood density and demographic rates. 3.,Several xylem traits were strongly correlated with each other, but wood density was not correlated with any of them. We also found no significant relationships between wood density and growth or mortality rate. Instead, growth was strongly related to xylem traits associated with hydraulic capacity (conduit diameter and a conductivity index) and to maximum height, whereas mortality rate was strongly correlated only with maximum height. The diameter and frequency of conduits exhibited a significant negative relationship, suggesting a trade-off, which restricted variation in wood density and growth rate, but not mortality rate. 4.,Our results suggest, for woody species in New Zealand, that growth rate is more closely linked to xylem traits determining hydraulic conductance, rather than wood density. We also found no evidence that denser woods conferred higher survival, or that risk of cavitation caused by wide conduits increased mortality. 5.,In summary, we found little support for the idea that wood density is a good proxy for position along a fast,slow rate-of-living continuum. Instead, the strong, negative relationship between vessel diameter and frequency may constrain the realized diversity of demographic niches of tree species in New Zealand. Trade-offs in function therefore have the potential to shape functional diversity and ecology of forest communities by linking selection on structure and function to population-level dynamics. [source]


Soil animals influence microbial abundance, but not plant,microbial competition for soil organic nitrogen

FUNCTIONAL ECOLOGY, Issue 5 2004
L. COLE
Summary 1In a microcosm experiment we examined the effects of individual species of microarthropods, and variations in microarthropod diversity of up to eight species, on soil microbial properties and the short-term partitioning of a dual-labelled organic nitrogen source (glycine-2- 13C- 15N) between a grassland plant, Agrostis capillaris, and the soil microbial biomass, to determine how soil fauna and their diversity influence plant,microbial competition for organic N. 2We hypothesized that variations in the diversity of animals would influence the partitioning of 15N inputs between plants and the microbial biomass, due to the effect of animal grazing on the microbial biomass, and hence its ability to sequester N. 3Certain individual species of Collembola influenced the microbial community of the soil. Folsomia quadrioculata reduced microbial biomass, whereas Mesaphorura macrochaeta enhanced arbuscular mycorrhizal (AM) colonization of A. capillaris roots. Effects of increasing species richness of microarthropods on microbial biomass and AM colonization were detected, but these effects could be interpreted in relation to the presence or absence of individual species. 4Microbial uptake of added 15N was not affected by the presence of any of the individual species of animal in the monoculture treatments. Similarly, increasing diversity of microarthropods had no detectable effect on microbial 15N. 5Root and shoot uptake of 15N was also largely unaffected by both single species and variations in diversity of microarthropods. However, one collembolan species, Ceratophysella denticulata, reduced root 15N capture when present in monoculture. We did not detect 13C in plant tissue under any experimental treatments, indicating that all N was taken up by plants after mineralization. 6Our data suggest that, while single species and variations in diversity of microarthropods influence microbial abundance in soil, there is no effect on microbial or plant uptake of N. Overall, these data provide little support for the notion that microbial-feeding soil animals are regulators of microbial,plant competition for N. [source]


Indigenous Methodologies: Suggestions for Junior Researchers

GEOGRAPHICAL RESEARCH, Issue 1 2010
NAOHIRO NAKAMURA
Abstract Indigenous methodologies in geography have recently been developed to decolonise Western dominated paradigms. It has been argued that research which does not benefit Indigenous communities should not be conducted. However, Indigenous methodologies are not taught in many post-secondary institutions. Therefore, when they pursue Indigenous topics, many junior researchers are self-taught in these methodologies. However, these methodologies cannot be defined simply and they are too diverse to be learnt in a short period. In Japan, Indigenous peoples are not widely recognised and research on contemporary Indigenous issues is limited. The concept of Indigenous methodologies is rarely discussed. Because of this, Japanese researchers rarely identify their research as adopting an Indigenous methodology. Indigenous researchers are thereby discouraged from pursuing Indigenous methodologies. Furthermore, a methodology or a thesis statement used by researchers to reflect Indigenous perspectives often gets little support from Indigenous peoples. My master's research on the Ainu mirrored this situation. While Indigenous methodologies remain difficult to learn, junior researchers should not be discouraged from this form of engagement. Practical suggestions are therefore necessary to encourage their use and application. Based on my experience, I suggest that researchers approach Indigenous communities from a learning perspective. This would encourage open-mindedness and sensitivity. Researchers should also be prepared and willing to refine their research questions and to continue their literature searches after their fieldwork is completed. These strategies could limit misinterpretation and exploitation of Indigenous knowledges and peoples. [source]


Change in the Concentration of Employment in Computer Services: Spatial Estimation at the U.S. Metro County Level

GROWTH AND CHANGE, Issue 1 2007
DONALD GRIMES
ABSTRACT This article models the concentration of computer services activity across the U.S. with factors that incorporate spatial relationships. Specifically, we enhance the standard home-area study with an analysis that allows conditions in neighboring counties to affect the concentration of employment in the home county. We use county-level data for metropolitan areas between 1990 and 1997. To measure change in employment concentration, we use the change in location quotients for SIC 737, which captures employment concentration changes caused by both the number of firms and the scale of their activity relative to the national average. After controlling for local demand for computer services, our results support the importance of the presence of a qualified labor supply, interindustry linkages, proximity to a major airport, and spatial processes in explaining changes in computer services employment concentration, finding little support for the influence of cost factors. Our enhanced model reveals interjurisdictional relationships among these metro counties that could not be captured with standard estimates by state, metropolitan statistical area (MSA), or county. Using counties within MSAs, therefore, provides more general results than case studies but still allows measurement of local interactions. [source]


Identifying the Role of Moral Hazard in International Financial Markets

INTERNATIONAL FINANCE, Issue 1 2004
Steven B. Kamin
Abstract Considerable attention has been paid to the possibility that large-scale IMF-led financing packages may have distorted incentives in international financial markets, leading private investors to provide more credit to emerging market countries, and at lower interest rates, than might otherwise have been the case. Yet, prior attempts to identify such distortions have yielded mixed evidence, at best. This paper makes three contributions to our ability to assess the empirical importance of moral hazard in international financial markets. First, it is argued that, because large international ,bail-outs' did not commence until the 1995 Mexican crisis, financial indicators prior to that time could not have reflected a significant degree of this type of moral hazard. Therefore, one test for the existence of moral hazard is that the access of emerging markets to international credit is significantly easier than it was prior to 1995. Second, the paper argues that because private investors expect large-scale IMF-led packages to be extended primarily to economically or geo-politically important countries, moral hazard, if it exists, should lead these countries to have easier terms of access to credit than smaller, non-systemically important countries. Finally, in addition to looking at bond spreads, the focus of earlier empirical analyses of moral hazard, the paper also examines trends in capital flows to gauge the access of emerging market countries to external finance. Looking at the evidence in light of these considerations, the paper concludes that there is little support for the view that moral hazard is significantly distorting international capital markets at the present time. [source]


Maternal medication use and the risk of brain tumors in the offspring: The SEARCH international case-control study

INTERNATIONAL JOURNAL OF CANCER, Issue 5 2006
Amanda H. Cardy
Abstract N -nitroso compounds (NOC) have been associated with carcinogenesis in a wide range of species, including humans. There is strong experimental data showing that nitrosamides (R1NNO·COR2), a type of NOC, are potent neuro-carcinogens when administered transplacentally. Some medications are a concentrated source of amides or amines, which in the presence of nitrites under normal acidic conditions of the stomach can form NOC. Therefore, these compounds, when ingested by women during pregnancy, may be important risk factors for tumors of the central nervous system in the offspring. The aim of the present study was to test the association between maternal use of medications that contain nitrosatable amines or amides and risk of primary childhood brain tumors (CBT). A case-control study was conducted, which included 1,218 cases and 2,223 population controls, recruited from 9 centers across North America, Europe and Australia. Analysis was conducted for all participants combined, by tumor type (astroglial, primitive neuroectodermal tumors and other glioma), and by age at diagnosis (,5 years; >5 years). There were no significant associations between maternal intake of medication containing nitrosatable amines or amides and CBT, for all participants combined and after stratification by age at diagnosis and histological subtype. This is the largest case-control study of CBT and maternal medications to date. Our data provide little support for an association between maternal use of medications that may form NOC and subsequent development of CBT in the offspring. © 2005 Wiley-Liss, Inc. [source]


Risk factors for body dissatisfaction in adolescent boys and girls: A prospective study

INTERNATIONAL JOURNAL OF EATING DISORDERS, Issue 4 2004
Katherine Presnell
Objective Despite evidence that body dissatisfaction predicts the onset of eating pathology and depression, few prospective studies have investigated predictors of body dissatisfaction. Method We examined risk factors for body dissatisfaction using prospective data from 531 adolescent boys and girls. Results Elevations in body mass, negative affect, and perceived pressure to be thin from peers, but not thin-ideal internalization, social support deficits, or perceived pressure to be thin from family, dating partners, or media, predicted increases in body dissatisfaction. Gender moderated the effect of body mass on body dissatisfaction and revealed a significant quadratic component for boys, but not girls. Gender also moderated negative affect. Discussion Results support the assertion that certain sociocultural, biologic, and interpersonal factors increase the risk for body dissatisfaction, but differ for boys and girls. Results provided little support for other accepted risk factors for body dissatisfaction. © 2004 by Wiley Periodicals, Inc. Int J Eat Disord 36: 389,401, 2004. [source]


Cranioplasty in ancient Peru: a critical review of the evidence, and a unique case from the Cuzco area

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2010
J. W. Verano
Abstract Cranioplasty is a well-known procedure in modern neurosurgery. Although some authors have claimed it was also performed by prehistoric trepanners in various parts of the world, there is little hard evidence to support this. Here we review various claims of cranioplasty in Peru, where trepanation was widely practised in Prehispanic times. We find little support for assertions that cranioplasty was common. One recently discovered burial from the Cuzco region, however, provides the first documented case of the reinsertion of a bone plug into a trepanation opening. Copyright © 2008 John Wiley & Sons, Ltd. [source]


The use of size,frequency diagrams to characterize prehistoric fish catches and to assess human impact on inshore fisheries

INTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 1-2 2001
Foss Leach
Abstract Archaeological collections of fish bones from previously excavated sites in New Zealand are being re-examined and selected bones measured in order to estimate original fish size, reconstruct prehistoric fish catches and assess human impact on the fishery over the course of about 800 years of New Zealand prehistory. Several problems hamper this research, such as small sample sizes, lack of significant stratigraphy at many sites, inconsistent field collection strategies and failure to retain all of the material after initial analysis. Although some common fish species show a significant decline in mean size between pre-European and early historic samples on the one hand, and modern populations on the other, we have found little support for the common belief that there was a decline in mean fish size during the pre-European period. We have observed increases over time in the mean size of snapper (Pagrus auratus), blue cod (Parapercis colias) and undifferentiated species of Labridae from several sites scattered throughout New Zealand. Distinguishing between changes in fish population structures owing to natural processes, such as surface sea water changes, and those which are the result of human over-fishing is not simple, because both processes can operate simultaneously. We draw on modern fish quota management models to separate these processes. Important factors for each species are inshore biomass and the recruitment rate at different temperature regimes. In the case of blue cod, we find that there are signs in the catch diagrams of changes in fishing technology, and that 30,80% of catches are undersized fish in terms of modern management criteria. Copyright © 2001 John Wiley & Sons, Ltd. [source]


Transport protocols in multicast via satellite

INTERNATIONAL JOURNAL OF SATELLITE COMMUNICATIONS AND NETWORKING, Issue 6 2004
Gun Akkor
Abstract In a wide variety of broadband applications, there is a need to distribute information to a potentially large number of receiver sites that are widely dispersed from each other. Communication satellites are a natural technology option and are extremely well suited for carrying such services because of the inherent broadcast capability of the satellite channel. Despite the potential of satellite multicast, there exists little support for multicast services over satellite networks. Although several multicast protocols have been proposed for use over the Internet, they are not optimized for satellite networks. One of the key multicast components that is affected when satellite networks are involved in the communication is the transport layer. In this paper, we attempt to provide an overview of the design space and the ways in which the network deployment and application requirements affect the solution space for transport layer schemes in a satellite environment. We also highlight some of the issues that are critical in the development of next generation satellite multicast services. Copyright © 2004 John Wiley & Sons, Ltd. [source]


Asymmetries in Transatlantic Monetary Policy-making: Does the ECB Follow the Fed?,

JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 5 2005
ANSGAR BELKE
The belief that the European Central Bank (ECB) follows the US Federal Reserve (the Fed) in setting its policy is so entrenched with market participants and commentators that the search for empirical support would seem to be a trivial task. However, this is not the case. We find that the ECB is indeed often influenced by the Fed, but the reverse is true at least as often if one considers longer sample periods. There is empirically little support for the proposition that there has for a long time been a systematic asymmetric leader-follower relationship between the ECB and the Fed. Only after September 2001 is there more evidence of such an asymmetry. There is a clear-cut structural break between the period pre-economic and monetary union (EMU) and EMU itself in terms of the relationship between short-term interest rates on both sides of the Atlantic. [source]


Predicting plant species' responses to grazing

JOURNAL OF APPLIED ECOLOGY, Issue 5 2001
Peter A. Vesk
Summary 1The aim of this study was to identify whether plant species show consistent responses to livestock grazing. The analyses were based on 35 published studies from Australian rangelands providing 55 species response lists. The primary data set comprised 1554 responses from 829 species. 2Eight-hundred and twenty-nine species were categorized as increasers, decreasers or neutral under grazing. Of 324 species that occurred in at least two response lists, 133 (41%) responded inconsistently, increasing at least once and decreasing at least once. While 59% of species responded consistently, these results suggest that our ability to predict vegetation change under grazing is limited. 3Particular species were not inherently more or less consistent. Rather, as species occurred in more trials, the likelihood of at least one opposite response increased; no species that occurred at least eight times was wholly consistent. A binomial model indicated that the probability of an opposite response, across all species, was 0·275. 4Contrary responses within species must result from context rather than from species' traits. Species were more likely to decrease in response to grazing at lower rainfall than at higher rainfall. Forbs tended to increase under grazing at sites where wet seasons were cooler. Changing the grazing animal was weakly correlated with change in response direction, although not enough for it to be useful for manipulating pasture composition. We found little support for ideas that different responses within species are due to differences in alternative forage available, or due to non-linearity of response to grazing intensity. 5At present it appears we can predict species response direction about three-quarters of the time, at a continental scale. This represents an upper limit of the reliability of prediction based on species' traits alone. Presently we do not know what aspects of the context might allow us to predict reliably the remaining one-quarter of responses. [source]


Explaining the global pattern of protected area coverage: relative importance of vertebrate biodiversity, human activities and agricultural suitability

JOURNAL OF BIOGEOGRAPHY, Issue 8 2008
Colby 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]


REVIEW: The evolution of polyembryony in parasitoid wasps

JOURNAL OF EVOLUTIONARY BIOLOGY, Issue 9 2010
M. SEGOLI
Abstract Polyembryony has evolved independently in four families of parasitoid wasps. We review three main hypotheses for the selective forces favouring this developmental mode in parasitoids: polyembryony (i) reduces the costs of egg limitation; (ii) reduces the genetic conflict among offspring; and (iii) allows offspring to adjust their numbers to the quality of the host. Using comparative data and verbal and mathematical arguments, we evaluate the relative importance of the different selective forces through different evolutionary stages and in the different groups of polyembryonic wasps. We conclude that reducing the cost of egg limitation is especially important when large broods are favoured. Reducing genetic conflict may be most important when broods are small, thus might have been important during, or immediately following, the initial transition from monoembryony to polyembryony. Empirical data provide little support for the brood-size adjustment hypothesis, although it is likely to interact with other selective forces favouring polyembryony. [source]


Preference,performance relationship and influence of plant relatedness on host use by Pityogenes chalcographus L.

AGRICULTURAL AND FOREST ENTOMOLOGY, Issue 4 2009
Coralie Bertheau
Abstract 1Pityogenes chalcographus L. (Coleoptera: Scolytinae) causes damage in European coniferous forests, primarily on Picea abies L. Karst., but is also recorded on other native and exotic Pinaceae species. Estimating the adequacy between adult preference and larval performance of this beetle among its host-range, as well as the influence of plant taxonomic relatedness on these parameters, would provide useful information on the beetle's ability to shift onto novel hosts. 2Choice and no-choice assays were conducted under laboratory conditions. Adult preference and larval performance parameters among two native (Pinus sylvestris L. and Picea abies) and three exotic north American [Pinus contorta Dougl., Picea sitchensis (Bong.) Carr. and Pseudotsuga menziesii Mirbel (Franco)] conifer species were measured. 3Pityogenes chalcographus exhibited a significant positive relationship between preference and performance. Picea abies was both the preferred and the most suitable host species for larval development. The closest relative, P. sitchensis, was the second best choice in terms of preference and performance. Pseudotsuga menziesii occupied an intermediate position for both beetle preference and performance, and Pinus spp. were the least suitable hosts for beetle development. 4Adult preference and larval performance ranking among hosts provides little support to the plant taxonomic relatedness hypothesis. Taxonomic relatedness could play a role on the diet breadth, although only at a limited scale, within the genus Picea. At higher taxonomic levels, other factors such as bark thickness might be decisive. [source]


Verbal short-term memory in Down's syndrome: An articulatory loop deficit?

JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 2 2004
S. Vicari
Abstract Background Verbal short-term memory, as measured by digit or word span, is generally impaired in individuals with Down's syndrome (DS) compared to mental age-matched controls. Moving from the working memory model, the present authors investigated the hypothesis that impairment in some of the articulatory loop sub-components is at the base of the deficient maintenance and recall of phonological representations in individuals with DS. Methods Two experiments were carried out in a group of adolescents with DS and in typically developing children matched for mental age. In the first experiment, the authors explored the reliance of these subjects on the subvocal rehearsal mechanism during a word-span task and the effects produced by varying the frequency of occurrence of the words on the extension of the word span. In the second experiment, they investigated the functioning of the phonological store component of the articulatory loop in more detail. Results A reduced verbal span in DS was confirmed. Neither individuals with DS nor controls engaged in spontaneous subvocal rehearsal. Moreover, the data provide little support for defective functioning of the phonological store in DS. Conclusions No evidence was found suggesting that a dysfunction of the articulatory loop and lexical-semantic competence significantly contributed to verbal span reduction in subjects with DS. Alternative explanations of defective verbal short-term memory in DS, such as a central executive system impairment, must be considered. [source]


SPECIES PHYLOGENY OF COSMARIUM AND STAURASTRUM (DESMIDIACEAE) BASED ON RBC L SEQUENCES

JOURNAL OF PHYCOLOGY, Issue 2000
O.-M. Lee
Cosmarium and Staurastrum are the two most diverse genera of placoderm desmids (Family Desmidiaceae), with approximately 1100 and 800 species, respectively. Phylogenetic analysis of relationships of species has been extremely difficult. In a monograph of North American placoderm desmids, Prescott et al. described early phylogenetic work that concluded Staurastrum to be polyphyletic and certainly polymorphic. Likewise, Cosmarium has also been viewed as polyphyletic, and a number of workers have proposed splitting these genera. The classical view of West and West grouped species within each genus into two divisions and 6,8 sections based on wall features and semicell shape. We sequenced rbcL from 18 species of Cosmarium (2 divisions, 7 sections) and 12 species of Staurastrum (2 divisions and 7 sections) and performed a phylogenetic analysis (parsimony, maximum likelihood, bootstrap) using other placoderm desmids and Zygnematales as outgroups. The results exhibit little support for the monophyly of sections or divisions of the two genera. Furthermore, although there is support for the monophyly of clades within each genus, there is also support for a separate clade containing species from both genera. [source]


Behavioral Consequences of Repeated Nicotine During Adolescence in Alcohol-Preferring AA and Alcohol-Avoiding ANA Rats

ALCOHOLISM, Issue 2 2009
Heidi Kemppainen
Background:, Epidemiological studies suggest that exposure to nicotine at adolescent age is associated with increased potential to use alcohol and that genetic predisposition may further increase the risk. The present study addressed adolescent vulnerability to repeated nicotine exposure and its influence on subsequent ethanol self-administration by investigating interactions between nicotine-induced behavioral sensitization and voluntary ethanol consumption in alcohol preferring AA (Alko Alcohol) and alcohol nonpreferring ANA (Alko Non-Alcohol) rat lines selected for differential ethanol intake. Methods:, Adolescent and adult rats received 10 injections of nicotine (0.5 mg/kg s.c.), given every second day from postnatal day (Pnd) 27 and 75, respectively. Nicotine-induced (0.5 mg/kg) locomotor activity was measured acutely after the first injection, and after the repeated treatment with nicotine on Pnds 52 and 86 in the adolescent groups and on Pnd 99 in the adult groups. After this, acquisition of voluntary ethanol (10% v/v) consumption as well as nicotine-induced (0.5 mg/kg) ethanol intake was measured in the AA rats. Results:, Adolescent AA rats were more sensitive than adolescent ANA rats to the locomotor effects of nicotine. They were also stimulated more than adult AA rats, but such a difference was not found among ANA rats. Adolescent and adult rats did not differ in their susceptibility to nicotine-induced behavioral sensitization. Genetic predisposition to ethanol self-administration did not interact with development of behavioral sensitization in either adolescents or adults. Acquisition of ethanol intake was enhanced in the adolescent groups relative to the adult groups in a manner that was independent of the nicotine treatment. An increase in ethanol intake was found after challenging animals with nicotine, and this effect was enhanced in the nicotine-treated adolescent group. Conclusions:, These findings provide no or little support for the views that adolescent animals are more sensitive to the neurobehavioral effects of repeated exposure to nicotine and that exposure to nicotine in adolescence may contribute to enhanced vulnerability to ethanol abuse. Furthermore, genetic predisposition to high or low ethanol self-administration does not seem to be a factor that influences individual vulnerability to the neurobehavioral effects of repeated administration of nicotine. [source]