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Selected AbstractsPatterns of Nest Predation on Artificial and Natural Nests in ForestsCONSERVATION BIOLOGY, Issue 2 2004DAWN M. BURKE ave de bosque; depredación de nidos; éxito de nidos; experimento de nidos artificiales; nidos naturales Abstract:,Artificial nest experiments have been used in an attempt to understand patterns of predation affecting natural nests. A growing body of literature suggests that neither relative rates nor patterns of predation are the same for artificial and natural nests. We studied nest predation and daily mortality rates and patterns at real and artificial ground and shrub nests to test the validity of artificial nest experiments. We monitored 1667 artificial and 344 natural nests, over seven trials, in three regions, across 58 sites in Ontario. We controlled for many of the factors thought to be responsible for previously reported differences between predation rates on natural and artificial nests. Although artificial nests in our study resembled natural nests, contained eggs of appropriate size, shape, and color of target bird species, and were placed in similar microhabitats as natural nests, the rates of predation on these nests did not parallel rates on natural nests for any region in terms of absolute rate or pattern. Predation rates on artificial nests did not vary between years, as they tended to for natural nests, and the magnitude of predation pressure on artificial ground nests compared with shrub nests did not show the same pattern as that on natural nests. In general, rates of predation on artificial nests were significantly higher than on natural nests. Our results suggest that conclusions derived from artificial nest studies may be unfounded. Given that many influential ideas in predation theory are based on results of artificial nest experiments, it may be time to redo these experiments with natural nests. Resumen:,Se han utilizado experimentos con nidos artificiales con la intención de entender los patrones de depredación que afectan a los nidos naturales. La bibliografía sugiere que ni las tasas relativas ni los patrones de depredación son iguales para nidos artificiales y naturales. Estudiamos las tasas y patrones de depredación de nidos y de mortalidad diaria en nidos reales y artificiales sobre el suelo y en matorrales para probar la validez de los experimentos con nidos artificiales. Monitoreamos 1667 nidos artificiales y 344 nidos naturales, en siete pruebas, en tres regiones, en 58 sitios en Notario. Controlamos muchos de los factores que se piensa son responsables de diferencias entre tasas de depredación en nidos naturales y artificiales reportadas previamente. Aunque los nidos artificiales en nuestro estudio se asemejaron a nidos naturales, contenían huevos de tamaño, forma y color adecuados para la especie de ave y fueron colocados en microhábitats similares a los de nidos naturales, las tasas de depredación en estos nidos no fueron similares a las tasas en nidos naturales en ninguna región en términos de tasa o patrón absoluto. Las tasas de depredación en nidos artificiales no variaron de un año a otro, como fue la tendencia en nidos naturales, y la magnitud de la presión de depredación en nidos sobre el suelo comparada con nidos en arbustos no mostró el mismo patrón que la depredación en nidos naturales. Nuestros resultados sugieren que las conclusiones derivadas de estudios con nidos artificiales pueden ser infundadas. Debido a que muchas ideas influyentes en la teoría de la depredación se basan en los resultados de experimentos con nidos artificiales, puede haber llegado el momento de volver a realizar estos experimentos utilizando nidos naturales. [source] Activation of the basal forebrain by the orexin/hypocretin neuronesACTA PHYSIOLOGICA, Issue 3 2010E. Arrigoni Abstract The orexin neurones play an essential role in driving arousal and in maintaining normal wakefulness. Lack of orexin neurotransmission produces a chronic state of hypoarousal characterized by excessive sleepiness, frequent transitions between wake and sleep, and episodes of cataplexy. A growing body of research now suggests that the basal forebrain (BF) may be a key site through which the orexin-producing neurones promote arousal. Here we review anatomical, pharmacological and electrophysiological studies on how the orexin neurones may promote arousal by exciting cortically projecting neurones of the BF. Orexin fibres synapse on BF cholinergic neurones and orexin-A is released in the BF during waking. Local application of orexins excites BF cholinergic neurones, induces cortical release of acetylcholine and promotes wakefulness. The orexin neurones also contain and probably co-release the inhibitory neuropeptide dynorphin. We found that orexin-A and dynorphin have specific effects on different classes of BF neurones that project to the cortex. Cholinergic neurones were directly excited by orexin-A, but did not respond to dynorphin. Non-cholinergic BF neurones that project to the cortex seem to comprise at least two populations with some directly excited by orexin-A that may represent wake-active, GABAergic neurones, whereas others did not respond to orexin-A but were inhibited by dynorphin and may be sleep-active, GABAergic neurones. This evidence suggests that the BF is a key site through which orexins activate the cortex and promote behavioural arousal. In addition, orexins and dynorphin may act synergistically in the BF to promote arousal and improve cognitive performance. [source] The Declining Value-relevance of Accounting Information and Non-Information-based Trading: An Empirical Analysis,CONTEMPORARY ACCOUNTING RESEARCH, Issue 4 2004ALEX DONTOH Abstract Recently, a growing body of literature has suggested that financial statements have lost their value-relevance because of a shift from a traditional capital-intensive economy to a high-technology, service-oriented economy. These conclusions are based on studies that find a temporal decline in the association between stock prices and accounting information (earnings and book values). This paper empirically tests a theoretical prediction arising from the noisy rational expectations equilibrium model that suggests that the decline could be driven by non-information-based (NIB) trading activity, because such trading reduces the ability of stock prices to reflect accounting information. Specifically, Dontoh, Radhakrishnan, and Ronen (2004) show that when NIB trading increases, the R2s of a regression of stock price on accounting information declines. Our empirical tests confirm this prediction; that is, the decline in the association between stock prices and accounting information as measured by R2s is driven by an increase in NIB trading. [source] Board Characteristics and Audit Fees,CONTEMPORARY ACCOUNTING RESEARCH, Issue 3 2002Joseph V. Carcello Abstract This paper examines the relations between three board characteristics (independence, diligence, and expertise) and Big 6 audit fees for Fortune 1000 companies. To protect its reputation capital, avoid legal liability, and promote shareholder interests, a more independent, diligent, and expert board may demand differentially higher audit quality (greater assurance, which requires more audit work) than the Big 6 audit firms normally provide. The audit fee increases as the auditor's additional costs are passed on to the client, such that we expect positive relations between audit fees and the board characteristics examined. We find significant positive relations between audit fees and board independence, diligence, and expertise. The results persist when similar measures of audit committee "quality" are included in the model. The results add to the growing body of literature documenting relations between corporate governance mechanisms and various facets of the financial reporting and audit processes, as well as to our understanding of the determinants of audit fees. [source] Audit Committee Independence and Disclosure: choice for financially distressed firmsCORPORATE GOVERNANCE, Issue 4 2003Joseph V. Carcello This study examines the relation between audit committee independence and disclosure choice for financially distressed US firms. The tenor of both the financial statement notes and Management Discussion and Analysis (MD&A) is considered. For firms experiencing financial distress, there is a significant positive relation between the percentage of affiliated directors on the audit committee and the optimism of the going-concern discussion in both the notes and the MD&A. These results add to the growing body of literature documenting a relation between audit committee independence and financial reporting quality. [source] Towards a New Logic for Front End Management: From Drug Discovery to Drug Design in Pharmaceutical R&DCREATIVITY AND INNOVATION MANAGEMENT, Issue 2 2007Maria Elmquist Under pressure to innovate and be cost-effective at the same time, R&D departments are being challenged to develop new organizations and processes for Front End activities. This is especially true in the pharmaceutical industry. As drug development becomes more risky and costly, the discovery departments of pharmaceutical companies are increasingly being compelled to provide strong drug candidates for efficient development processes and quick market launches. It is argued that the Fuzzy Front End consists less of the discovery or recognition of opportunities than of the building of expanded concepts: the notion of concept generation is revisited, suggesting the need for a new logic for organizing Front End activities in order to support sustainable innovative product development. Based on an in-depth empirical study at a European pharmaceutical company, this paper contributes to improved understanding of the actual management practices used in the Front End. Using a design reasoning model (the C-K model), it also adds to the growing body of literature on the management of Front End activities in new product development processes. [source] RACE, FRIENDSHIP NETWORKS, AND VIOLENT DELINQUENCYCRIMINOLOGY, Issue 4 2006DANA L. HAYNIE Although a growing body of literature emphasizes the role of friendship networks and peer relations for youth involvement in violence and delinquency, little research has examined the role of friendship networks in understanding the varying involvement of different racial-ethnic groups in violence. Using data from approximately 13,000 respondents to the first two waves of the National Longitudinal Study of Adolescent Health (Add Health), we explore the ability of friendship networks to account for the differential rates of violence among racial-ethnic groups. In addition, we evaluate whether race moderates the degree to which friendship characteristics predict adolescent violence. Findings indicate significant differences in the structure and behavioral orientation of friendship networks across racial-ethnic identities. Moreover, incorporating characteristics of friendship networks into multivariate analyses accounts for greater involvement in violence among black and Hispanic youths. Network racial heterogeneity and friends' popularity also emerge as particular network characteristics that operate differently for black and white youth. [source] Roles of the actin-binding proteins in intracellular Ca2+ signallingACTA PHYSIOLOGICA, Issue 1 2009J. T. Chun Abstract Starfish oocytes undergo massive intracellular Ca2+ signalling during meiotic maturation and fertilization. Although the igniting stimulus of Ca2+ mobilization may differ in different cell contexts, its final leverage is usually the Ca2+ -releasing second messengers such as InsP3, cADPr and NAADP. The general scheme of intracellular Ca2+ release is that the corresponding receptors for these molecules serve as ion channels to release free Ca2+ from its internal stores such as the lumen of the endoplasmic reticulum. However, a growing body of evidence has suggested that intracellular Ca2+ release can be strongly modulated by the actin cytoskeleton. Although it is known that Ca2+ contributes to remodelling of the actin cytoskeleton, whether the actin cytoskeleton modulates Ca2+ signalling in return has not been much explored. An emerging candidate to answer to this reciprocal causality of Ca2+ and the actin cytoskeleton may be actin-binding proteins. In this review, we discuss how the actin cytoskeleton may fit into the known mechanisms of intracellular Ca2+ release, and propose two models to explain the experimental data. [source] THE SOCIAL ECOLOGY OF VIOLENCE AGAINST WOMEN,CRIMINOLOGY, Issue 2 2004JANET L. LAURITSEN Despite more than three decades of research on the topic of violence against women, the relative contribution of individual, family and community factors to victimization risk remains unknown. We use self-report data from the Area-Identified National Crime Victimization Survey to study the correlates of stranger, nonstranger and intimate,partner violence against women. Regardless of victim-offender relationship, we find that the risk for victimization is highest among young, single women with children, particularly those who have lived in the current home for relatively shorter periods. Area family and age composition appear to have stronger direct relationships with women's violence than poverty or racial composition measures. We also find there to be more similarities than differences in the individual, family, and community correlates of stranger, nonstranger and intimate partner violence. We discuss these findings as part of the growing body of multilevel literature on violence and on violence against women. [source] Women's Careers Beyond the Classroom: Changing Roles in a Changing WorldCURRICULUM INQUIRY, Issue 3 2001Nina Bascia Drawing from our own and others' research over the past decade and a half, we present four "readings," each illuminating a different dimension of women educators' career development, particularly their movement into work beyond the classroom. The majority of the participants in our studies are women who work for change in their classrooms, schools, and district organizations, using the opportunities, vehicles, and channels available,or apparent,to them. They do this work in professional and personal contexts that are continually changing, sometimes as a result of their own choices and actions and sometimes not. While there is a growing body of literature on women's movement into, and their lives in, educational administration, we are concerned here with the broader and more varied manifestations of leadership beyond the classroom. In the four readings, we bring together several strands in the literature on women educators' lives and careers. We first lay out the taken-for-granted oppositional contrasts in the educational discourses that have tended to obscure more complex understandings of work lives and careers. Next, we explore how the particular kinds of work available to women actually encourage some to move beyond narrow conceptions of the distinctions between classroom and nonclassroom work. Third, we discuss the developmental nature of individual career paths. Fourth, we note the spatial and temporal nature of leadership work by showing how it is influenced and changed by greater economic, social, and political forces. We believe that these multiple interpretations are required to understand the range and combination of influences that propel and compel women educators to take up various forms of leadership work beyond the classroom. [source] Nerve growth factor increases airway responses and decreases levels of exhaled nitric oxide during histamine challenge in an in vivo guinea-pig modelACTA PHYSIOLOGICA, Issue 2 2001S. G. Friberg There is a growing body of evidence supporting the idea that nerve growth factor (NGF) may be involved in the development of asthma-associated symptoms, such as airway hyper-responsiveness. Increased levels of NGF have recently been described in serum and in the airways of asthmatics. We have examined whether exhaled nitric oxide (NO) levels might be altered during the increased airway responses upon NGF treatment in guinea-pigs in vivo. Intravenous (i.v.) administration of histamine normally elicits a rapid peak in insufflation pressure (IP) and in exhaled NO, followed by a period of decreased concentrations of exhaled NO. Anaesthetized guinea-pigs were pre-treated intravenously with either saline, 4 or 80 ng kg,1 NGF 30 min before i.v. challenge with 16 ,g kg,1 histamine. At 80 ng kg,1 NGF significantly enhanced the airway obstruction caused by histamine, whereas the peak acute increase in exhaled NO was not enhanced. Following the increase, came a rapid drop, an effect enforced in the NGF treated animals. Subsequently, the time to return to 90% of resting exhaled NO was increased, from 12 min in saline-treated animals to 48 min in NGF-treated animals. Our data confirm that NGF can enhance airway responses to histamine. Moreover, our study shows a decrease in exhaled NO following a histamine challenge, an effect enhanced by NGF. A reduced ability to release exhaled NO may be a mechanism for increased airway responses during elevated NGF levels. The interaction between NGF and airway NO formation, and its relation to airway responses, merit further investigation. [source] An update on the role of glutamate in the pathophysiology of depressionACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010N. D. Mitchell Mitchell ND, Baker GB. An update on the role of glutamate in the pathophysiology of depression. Objective:, To review the literature on the involvement of glutamate (Glu), including its interactions with other neurochemical systems, in the pathophysiology of depression. Method:, A MEDLINE search using the terms glutamate, depression and major depressive disorder, was performed. Results:, Alterations in proteins involved in glutamatergic signalling are implicated in variations in behaviour in animal models of depression. Drugs acting at Glu receptors appear to have antidepressant-like effects in these models, and traditional antidepressant pharmacotherapies act on the glutamatergic system. Recent evidence from genetic studies and in vivo spectroscopy also correlate glutamatergic dysfunction with depression. Trials of N -methyl- d -aspartate receptor antagonists in humans have provided mixed results. Conclusion:, A growing body of evidence indicates that the glutamatergic system is involved in the pathophysiology of depression, and may represent a target for intervention. [source] Candidate genes and the behavioral phenotype in 22q11.2 deletion syndromeDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2008Sarah E. Prasad Abstract There is an overwhelming evidence that children and adults with 22q11.2 deletion syndrome (22q11.2DS) have a characteristic behavioral phenotype. In particular, there is a growing body of evidence that indicates an unequivocal association between 22q11.2DS and schizophrenia, especially in adulthood. Deletion of 22q11.2 is the third highest risk for the development of schizophrenia, with only a greater risk conferred by being the child of two parents with schizophrenia or the monozygotic co-twin of an affected individual. Both linkage and association studies of people with schizophrenia have implicated several susceptibility genes, of which three are in the 22q11.2 region; catechol- o -methyltransferase (COMT), proline dehydrogenase (PRODH), and Gnb1L. In addition, variation in Gnb1L is associated with the presence of psychosis in males with 22q11.2DS. In mouse models of 22q11.2DS, haploinsufficiency of Tbx1 and Gnb1L is associated with reduced prepulse inhibition, a schizophrenia endophenotype. The study of 22q11.2DS provides an attractive model to increase our understanding of the development and pathogenesis of schizophrenia and other psychiatric disorders in 22q11.2DS and in wider population. © 2008 Wiley-Liss, Inc. Dev Disabil Res Rev 2008;14:26,34. [source] The development of "roughness" in the play fighting of rats: A Laban Movement Analysis perspectiveDEVELOPMENTAL PSYCHOBIOLOGY, Issue 1 2003Afra Foroud Abstract With increasing age, rats, when play fighting, become rougher. In part, this change can be accounted for by the increasing likelihood of using adult-typical fighting tactics. However, even when using the same tactics, adults appear rougher than juveniles in their play. In this study, videotaped sequences of play fighting in rats from the juvenile (30 days) to the post-pubertal (70 days) period were analyzed using Laban Movement Analysis (LMA). Movement qualities called Effort Factors in LMA captured the character of some of this change. Juveniles tended to use Indulging Efforts, whereas older rats tended to use Condensing Efforts. The latter are related to performing movements that are more controlled. This greater level of control was also evident in the way older rats maintained postural support during play fights. When standing over supine partners, juveniles are more likely to stand on the partner with all four paws, reducing their postural stability, and hence ability to control their partner's movements. Older rats are more likely to place their hind paws on the ground, thus providing a firmer anchor for movements with their upper bodies and forepaws. These age-related changes in behavior were found for both males and females. The findings lend support to a growing body of evidence that play fighting in the juvenile phase of rats is not just a more frequently occurring version of that present in adults, but rather, has unique organizational properties. © 2003 Wiley Periodicals, Inc. Dev Psychobiol 42: 35,43, 2003. [source] Screening for type 2 diabetes: an update of the evidenceDIABETES OBESITY & METABOLISM, Issue 10 2010R. K. Simmons A growing body of evidence on diabetes screening has been published during the last 10 years. Type 2 diabetes meets many but not all of the criteria for screening. Concerns about potential harms of screening have largely been resolved. Screening identifies a high-risk population with the potential to gain from widely available interventions. However, in spite of the findings of modelling studies, the size of the benefit of earlier initiation of treatment and the overall cost-effectiveness remains uncertain, in contrast to other screening programmes (such as for abdominal aortic aneurysms) that are yet to be fully implemented. There is also uncertainty about optimal specifications and implementation of a screening programme, and further work to complete concerning development and delivery of individual- and population-level preventive strategies. While there is growing evidence of the net benefit of earlier detection of individuals with prevalent but undiagnosed diabetes, there remains limited justification for a policy of universal population-based screening for type 2 diabetes at the present time. Data from ongoing studies should inform the key assumptions in existing modelling studies and further reduce uncertainty. [source] ,-cell preservation: a potential role for thiazolidinediones to improve clinical care in Type 2 diabetesDIABETIC MEDICINE, Issue 8 2005L. A. Leiter Abstract Type 2 diabetes is caused by progressively increasing insulin resistance coupled with deteriorating ,-cell function, and there is a growing body of evidence to suggest that both of these defects precede hyperglycaemia by many years. Several studies have demonstrated the importance of maintaining ,-cell function in patients with Type 2 diabetes. This review explores parameters used to indicate ,-cell dysfunction, in Type 2 diabetes and in individuals with a predisposition to the disease. A genetic element undoubtedly underlies ,-cell dysfunction; however, a number of modifiable components are also associated with ,-cell deterioration, such as chronic hyperglycaemia and elevated free fatty acids. There is also evidence for a link between pro-inflammatory cytokines and impairment of insulin-signalling pathways in the ,-cell, and the potential role of islet amyloid deposition in ,-cell deterioration continues to be a subject for debate. The thiazolidinediones are a class of agents that have demonstrated clinical improvements in indices of ,-cell dysfunction and have the potential to improve ,-cell function. Data are accumulating to show that this therapeutic group offers a number of advantages over traditionally employed oral agents, and these data demonstrate the growing importance of thiazolidinediones in Type 2 diabetes management. [source] All-cause mortality and fatal alcohol poisoning in Belarus, 1970,2005DRUG AND ALCOHOL REVIEW, Issue 5 2008YURY E. RAZVODOVSKY Abstract Introduction and Aims. Although alcohol appears to be an important contributor to the burden of disease in the countries of eastern Europe, little systematic research has been undertaken on its impact on mortality in the former Soviet republic of Belarus. There may be a number of factors underlying the particularly negative effect of alcohol on mortality in Belarus, including the pattern of drinking and use of surrogates. A solid body of research and empirical evidence suggests that hazardous patterns of alcohol consumption (binge drinking) lead to quicker and deeper intoxication, increasing the propensity for alcohol-related mortality. Design and Method. To estimate the aggregate level effect of binge drinking on the all-cause mortality rate, trends in the all-cause mortality and fatal alcohol poisoning rates (as a proxy for binge drinking) in Belarus from 1970 to 2005 were analysed employing AutoRegressive Integrated Moving Average (ARIMA) time,series analysis in order to assess a bivariate relationship between the two time,series. Results. The results of time,series analysis suggest a close relationship between all-cause mortality and fatal alcohol poisoning rates at the population level. Conclusions. This study supports the hypothesis that alcohol and all-cause mortality are connected closely in countries where the drinking culture is characterised by heavy drinking episodes and adds to the growing body of evidence that a substantial proportion of total mortality in Belarus is due to acute effects of binge drinking. [source] T-type calcium channels: an emerging therapeutic target for the treatment of painDRUG DEVELOPMENT RESEARCH, Issue 4 2006Terrance P. Snutch Abstract It has become generally accepted that presynaptic high voltage,activated N-type calcium channels located in the spinal dorsal horn are a validated clinical target for therapeutic interventions associated with severe intractable pain. Low voltage,activated (T-type) calcium channels play a number of critical roles in nervous system function, including controlling thalamocortical bursting behaviours and the generation of spike wave discharges associated with slow wave sleep patterns. There is a growing body of evidence that T-type calcium channels also contribute in several ways to both acute and neuropathic nociceptive behaviours. In the one instance, the Cav3.1 T-type channel isoform likely contributes an anti-nociceptive function in thalamocortical central signalling, possibly through the activation of inhibitory nRT neurons. In another instance, the Cav3.2 T-type calcium channel subtype acts at the level of primary afferents in a strongly pro-nociceptive manner in both acute and neuropathic models. While a number of classes of existing clinical agents non-selectively block T-type calcium channels, there are no subtype-specific drugs yet available. The development of agents selectively targeting peripheral Cav3.2 T-type calcium channels may represent an attractive new avenue for therapeutic intervention. Drug Dev. Res. 67:404,415, 2006. © 2006 Wiley-Liss, Inc. [source] The impact of a supervised injecting facility on ambulance call-outs in Sydney, AustraliaADDICTION, Issue 4 2010Allison M. Salmon ABSTRACT Aims Supervised injecting facilities (SIFs) are effective in reducing the harms associated with injecting drug use among their clientele, but do SIFs ease the burden on ambulance services of attending to overdoses in the community? This study addresses this question, which is yet to be answered, in the growing body of international evidence supporting SIFs efficacy. Design Ecological study of patterns in ambulance attendances at opioid-related overdoses, before and after the opening of a SIF in Sydney, Australia. Setting A SIF opened as a pilot in Sydney's ,red light' district with the aim of accommodating a high throughput of injecting drug users (IDUs) for supervised injecting episodes, recovery and the management of overdoses. Measurements A total of 20 409 ambulance attendances at opioid-related overdoses before and after the opening of the Sydney SIF. Average monthly ambulance attendances at suspected opioid-related overdoses, before (36 months) and after (60 months) the opening of the Sydney Medically Supervised Injecting Centre (MSIC), in the vicinity of the centre and in the rest of New South Wales (NSW). Results The burden on ambulance services of attending to opioid-related overdoses declined significantly in the vicinity of the Sydney SIF after it opened, compared to the rest of NSW. This effect was greatest during operating hours and in the immediate MSIC area, suggesting that SIFs may be most effective in reducing the impact of opioid-related overdose in their immediate vicinity. Conclusions By providing environments in which IDUs receive supervised injection and overdose management and education SIF can reduce the demand for ambulance services, thereby freeing them to attend other medical emergencies within the community. [source] Placing Progress: Contextual Inequality and Immigrant Incorporation in the United StatesECONOMIC GEOGRAPHY, Issue 3 2008Jamie Goodwin-White Abstract This article contributes to the growing body of research on the economic incorporation of immigrants by considering the relative wages of immigrants, the adult children of immigrants, and the U.S.-born children of U.S. parentage. By disaggregating these three groups racially, comparing entire wage distributions, and comparing the immigrant cities of New York and Los Angeles with the United States overall, it presents a perspective on the complicated contexts of the intergenerational progress of immigrants. In addition to comparing the groups' relative positions in 1990 and 2000, the article decomposes relative wages such that differences in the educational composition of groups can be isolated from residual wage inequality. This research is of interest because consideration of the U.S.-born or educated children of immigrants invokes questions of social mobility and the persistence of ethnic inequality more generally. The article also contributes to a theoretical debate over place and immigrants' progress by examining the second generation, for whom residence in immigrant cities is often theorized as detrimental to economic incorporation. Finally, it introduces a substantial analysis of local wage structures to questions of immigrants' intergenerational economic progress to a much greater extent than has previously been the case. The results suggest that prospects for immigrants' economic incorporation are geographically specific and should be assessed across multiple generations as a result of the continuing contexts of racial wage inequality [source] The Impact of Interorganizational Imitation on New Venture International Entry and PerformanceENTREPRENEURSHIP THEORY AND PRACTICE, Issue 1 2010Stephanie A. Fernhaber We examine the impact of interorganizational imitation on new venture international entry and subsequent performance. Using a sample of 150 U.S.-based publicly held new ventures, we find that new venture international entry is in part an imitative response to the internationalization of other firms in the venture's home country industry and/or subsets of firms with certain traits or outcomes. We also find that interorganizational imitation moderates the relationship between new venture international entry and profitability, but not the relationship between new venture international entry and sales growth. These findings contribute to the growing body of literature on new venture internationalization. [source] Strategic Entrepreneurship: Exploring Different Perspectives of an Emerging ConceptENTREPRENEURSHIP THEORY AND PRACTICE, Issue 1 2009Donald F. Kuratko Within the entrepreneurship and strategic management domains there has been a movement by scholars to combine certain aspects of both areas to create a new concept of strategic entrepreneurship. To date, however, there remains much to know about what constitutes this concept. This special issue is the result of a unique research conference in Germany where some of the world's most renowned scholars gathered to explore this concept in depth. The set of articles in this special issue examine different perspectives that relate to strategic entrepreneurship and we believe contribute to the growing body of knowledge on this concept by examining diverse scholarly topics. This introduction provides the overview of the perspectives contained in strategic entrepreneurship and argues for the importance of embracing diverse views at this stage rather than attempting to restrict the analysis of this emerging topic. [source] Cannabis use and later life outcomesADDICTION, Issue 6 2008David M. Fergusson ABSTRACT Aim To examine the associations between the extent of cannabis use during adolescence and young adulthood and later education, economic, employment, relationship satisfaction and life satisfaction outcomes. Design A longitudinal study of a New Zealand birth cohort studied to age 25 years. Measurements Measures of: cannabis use at ages 14,25; university degree attainment to age 25; income at age 25; welfare dependence during the period 21,25 years; unemployment 21,25 years; relationship quality; life satisfaction. Also, measures of childhood socio-economic disadvantage, family adversity, childhood and early adolescent behavioural adjustment and cognitive ability and adolescent and young adult mental health and substance use. Findings There were statistically significant bivariate associations between increasing levels of cannabis use at ages 14,21 and: lower levels of degree attainment by age 25 (P < 0.0001); lower income at age 25 (P < 0.01); higher levels of welfare dependence (P < 0.0001); higher unemployment (P < 0.0001); lower levels of relationship satisfaction (P < 0.001); and lower levels of life satisfaction (P < 0.0001). These associations were adjusted for a range of potentially confounding factors including: family socio-economic background; family functioning; exposure to child abuse; childhood and adolescent adjustment; early adolescent academic achievement; and comorbid mental disorders and substance use. After adjustment, the associations between increasing cannabis use and all outcome measures remained statistically significant (P < 0.05). Conclusions The results of the present study suggest that increasing cannabis use in late adolescence and early adulthood is associated with a range of adverse outcomes in later life. High levels of cannabis use are related to poorer educational outcomes, lower income, greater welfare dependence and unemployment and lower relationship and life satisfaction. The findings add to a growing body of knowledge regarding the adverse consequences of heavy cannabis use. [source] Probabilistic risk assessment of reproductive effects of polychlorinated biphenyls on bottlenose dolphins (Tursiops truncatus) from the Southeast United States coastENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 12 2002Lori H. Schwacke Abstract High levels of polychlorinated biphenyls (PCBs) have been reported in the tissues of some species of marine mammals. The high concentrations are of concern because a growing body of experimental evidence links PCBs to deleterious effects on reproduction, endocrine homeostasis, and immune system function. Much of the recent research has focused on determining the exposure of marine mammal populations to PCBs, but very little effort has been devoted to the actual risk assessments that are needed to determine the expected impacts of the documented exposures. We describe a novel risk assessment approach that integrates measured tissue concentrations of PCBs with a surrogate dose-response relationship and leads to predictions of health risks for marine mammals as well as to the uncertainties associated with these predictions. Specifically, we use PCB tissue residue data from three populations of bottlenose dolphins (Tursiops truncatus), study the feasibility of published dose-response data from a surrogate species, and combine this information to estimate the risk of detrimental reproductive effects in female dolphins. Our risk analyses for dolphin populations near Beaufort (NC, USA), Sarasota (FL, USA), and Matagorda Bay (TX, USA) indicate a high likelihood that reproductive success, primarily in primiparous females, is being severely impaired by chronic exposure to PCBs. Excess risk of reproductive failure, measured in terms of stillbirth or neonatal mortality, for primiparous females was estimated as 60% (Beaufort), 79% (Sarasota), and 78% (Matagorda Bay). Females of higher parity, which have previously off-loaded a majority of their PCB burden, exhibit a much lower risk. [source] The Blood,Brain Barrier and EpilepsyEPILEPSIA, Issue 11 2006Emily Oby Summary:, During the past several years, there has been increasing interest in the role of the blood,brain barrier (BBB) in epilepsy. Advances in neuroradiology have enhanced our ability to image and study the human cerebrovasculature, and further developments in the research of metabolic deficiencies linked to seizure disorders (e.g., GLUT1 deficiency), neuroinflammation, and multiple drug resistance to antiepileptic drugs (AEDs) have amplified the significance of the BBB's relationship to epilepsy. Prior to 1986, BBB research in epilepsy focused on three main areas: ultrastructural studies, brain glucose availability and transport, and clinical uses of AEDs. However, contrast-based imaging techniques and medical procedures such as BBB disruption provided a framework that demonstrated that the BBB could be reversibly disrupted by pathologic or iatrogenic manipulations, with important implications in terms of CNS drug delivery to "multiple drug resistant" brain. This concept of BBB breakdown for therapeutic purposes has also unveiled a previously unrecognized role for BBB failure as a possible etiologic mechanism in epileptogenesis. Finally, a growing body of evidence has shown that inflammatory mechanisms may participate in the pathological changes observed in epileptic brain, with increasing awareness that blood-borne cells or signals may participate in epileptogenesis by virtue of a leaky BBB. In this article we will review the relationships between BBB function and epilepsy. In particular, we will illustrate consensus and divergence between clinical reality and animal studies. [source] Tests of causal linkages between cannabis use and psychotic symptomsADDICTION, Issue 3 2005David M. Fergusson ABSTRACT Aim To examine possible causal linkages between cannabis use and psychosis using data gathered over the course of a 25-year longitudinal study. Design A 25-year longitudinal study of the health, development and adjustment of a birth cohort of 1265 New Zealand children (635 males, 630 females). Setting The Christchurch Health and Development Study, a general community sample. Participants A total of 1055 participants from the Christchurch Health and Development Study (CHDS) cohort for whom data on cannabis use and psychotic symptoms were available on at least one occasion from 18, 21 and 25 years. Measurements As part of this study, data were gathered on frequency of cannabis use and psychotic symptoms at ages 18, 21 and 25 years. Findings Regression models adjusting for observed and non-observed confounding suggested that daily users of cannabis had rates of psychotic symptoms that were between 1.6 and 1.8 times higher (P < 0.001) than non-users of cannabis. Structural equation modelling suggested that these associations reflected the effects of cannabis use on symptom levels rather than the effects of symptom levels on cannabis use. Conclusions The results of the present study add to a growing body of evidence suggesting that regular cannabis use may increase risks of psychosis. The present study suggests that: (a) the association between cannabis use and psychotic symptoms is unlikely to be due to confounding factors; and (b) the direction of causality is from cannabis use to psychotic symptoms. [source] Feasibility of an exercise rehabilitation programme for cancer patientsEUROPEAN JOURNAL OF CANCER CARE, Issue 4 2006C. STEVINSON bsc, research fellow A growing body of evidence indicates the benefits of exercise as a rehabilitation intervention for cancer patients. However, few hospitals offer exercise-based rehabilitation programmes to patients. This study evaluated the feasibility and acceptability of a group-based exercise programme for cancer patients attending a local oncology centre. The intervention consisted of a weekly instructor-led circuit training class supplemented by home-based activity 4 days/week for 10 weeks. From 28 eligible patients, 12 were recruited (43%), of whom nine completed the intervention (75%). The three withdrawals were due to worsening of disease. Adherence (mean of 7.5 classes attended and 4 days/week of home activity performed) and tolerability (no adverse events) were good. Positive features of the programme identified in interviews with participants included the variety and scope of the exercises, and the empathetic but positive approach of the instructors. The small group format was highly valued with participants receiving social support and inspiration from each other. Perceived outcomes included improved fitness, reduced fatigue, enjoyment, enhanced mood and a sense of achievement. Several participants felt that the intervention represented a stepping stone to becoming habitual exercisers. Results suggested that the programme was feasible and acceptable to patients, but uptake was low, indicating a need for more effective recruitment strategies in order for a cost-effective service to be implemented. [source] Getting to the crux of the matter: IL-23 and Th17 cell accumulation in the CNSEUROPEAN JOURNAL OF IMMUNOLOGY, Issue 7 2009Benjamin M. Segal Abstract IL-23 plays a critical role in EAE induced by the active immunization of C57BL/6 mice with an immunodominant epitope of myelin oligodendrocyte glycoprotein (MOG35,55). It was initially assumed that the pathogenic effects of IL-23 were directly related to the generation, expansion and/or stabilization of autoreactive CD4+ Th17 cells. However, a number of recent studies have uncovered discrepancies between the requirement for IL-23, as opposed to Th17 cells or their products (IL-17A, IL-17F and IL-22), in the development of EAE. In this issue of the European Journal of Immunology, it is demonstrated that impairment of IL-23 signaling does not impede the expansion of myelin-specific CD4+ T cells in peripheral lymphoid tissues but inhibits their accumulation in the CNS. This paper contributes to a growing body of data that implicates IL-23 in the acquisition of CNS homing properties by autoreactive effector cells. [source] The orientation and dynamics of cell division within the plane of the developing vertebrate retinaEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 3 2004Marc S. Tibber Abstract The orientation of a dividing cell within the plane of the tissue plays an essential role in regulating cell fate in a range of developing structures. To assess its potential role in the developing vertebrate retina we used standard confocal microscopy of fixed tissue and time-lapse confocal imaging of living tissue to examine the orientation of cell division and mitotic spindle rotation within the plane of the retinal neuroepithelium. Based on the study of three rat strains and chick, we report in contrast to recent findings that during the main phase of cell production (E18,P4 in the rat and E6,E11 in the chick) dividing cells are randomly orientated with respect to key anatomical landmarks as well as the orientation of their dividing neighbours. Results from live imaging of neonatal rat retinae support these findings and suggest that unlike the developing cortex, in which metaphase plates often rotate extensively before coming to rest in anaphase, retinal mitotic spindle rotations prior to cell division are minimal. Furthermore, the orientation of metaphase entry largely defines that which is finally adopted during anaphase. Hence, the dynamics of metaphase progression through to anaphase in the retina appear to differ markedly from the brain, and cell divisions within the plane of the tissue are randomly orientated. These results contribute to a growing body of evidence that suggests that the current paradigm with respect to asymmetric division derived from the study of invertebrates cannot be generalized to the developing vertebrate nervous system. [source] Discussion on ,Personality psychology as a truly behavioural science' by R. Michael FurrEUROPEAN JOURNAL OF PERSONALITY, Issue 5 2009Article first published online: 14 JUL 200 Yes We Can! A Plea for Direct Behavioural Observation in Personality Research MITJA D. BACK and BORIS EGLOFF Department of Psychology, Johannes Gutenberg University Mainz, Germany mback@uni-leipzig.de Furr's target paper (this issue) is thought to enhance the standing of personality psychology as a truly behavioural science. We wholeheartedly agree with this goal. In our comment we argue for more specific and ambitious requirements for behavioural personality research. Specifically, we show why behaviour should be observed directly. Moreover, we illustratively describe potentially interesting approaches in behavioural personality research: lens model analyses, the observation of multiple behaviours in diverse experimentally created situations and the observation of behaviour in real life. Copyright © 2009 John Wiley & Sons, Ltd. The Categories of Behaviour Should be Clearly Defined PETER BORKENAU Department of Psychology, Martin-Luther University Halle-Wittenberg, Germany p.borkenau@psych.uni-halle.de The target paper is helpful by clarifying the terminology as well as the strengths and weaknesses of several approaches to collect behavioural data. Insufficiently considered, however, is the clarity of the categories being used for the coding of behaviour. Evidence is reported showing that interjudge agreement for retrospective and even concurrent codings of behaviour does not execeed interjudge agreement for personality traits if the categories being used for the coding of behaviour are not clearly defined. By contrast, if the behaviour to be registered is unambiguously defined, interjudge agreement may be almost perfect. Copyright © 2009 John Wiley & Sons, Ltd. Behaviour Functions in Personality Psychology PHILIP J. CORR Department of Psychology, Faculty of Social Sciences, University of East Anglia, Norwich, UK Philip.Corr@btopenworld.com Furr's target paper highlights the importance, yet under-representation, of behaviour in published articles in personality psychology. Whilst agreeing with most of his points, I remain unclear as to how behaviour (as specifically defined by Furr) relates to other forms of psychological data (e.g. cognitive task performance). In addition, it is not clear how the functions of behaviour are to be decided: different behaviours may serve the same function; and identical behaviours may serve different functions. To clarify these points, methodological and theoretical aspects of Furr's proposal would benefit from delineation. Copyright © 2009 John Wiley & Sons, Ltd. On the Difference Between Experience-Sampling Self-Reports and Other Self-Reports WILLIAM FLEESON Department of Psychology, Wake Forest University, Winston-Salem, NC, USA fleesonW@wfu.edu Furr's fair but evaluative consideration of the strengths and weaknesses of behavioural assessment methods is a great service to the field. As part of his consideration, Furr makes a subtle and sophisticated distinction between different self-report methods. It is easy to dismiss all self-reports as poor measures, because some are poor. In contrast, Furr points out that the immediacy of the self-reports of behaviour in experience-sampling make experience-sampling one of the three strongest methods for assessing behaviour. This comment supports his conclusion, by arguing that ESM greatly diminishes one the three major problems afflicting self-reports,lack of knowledge,and because direct observations also suffer from the other two major problems afflicting self-reports. Copyright © 2009 John Wiley & Sons, Ltd. What and Where is ,Behaviour' in Personality Psychology? LAURA A. KING and JASON TRENT Department of Psychology, University of Missouri, Columbia, USA kingla@missouri.edu Furr is to be lauded for presenting a coherent and persuasive case for the lack of behavioural data in personality psychology. While agreeing wholeheartedly that personality psychology could benefit from greater inclusion of behavioural variables, here we question two aspects of Furr's analysis, first his definition of behaviour and second, his evidence that behaviour is under-appreciated in personality psychology. Copyright © 2009 John Wiley & Sons, Ltd. Naturalistic Observation of Daily Behaviour in Personality Psychology MATTHIAS R. MEHL Department of Psychology, University of Arizona, Tucson, AZ, USA mehl@email.arizona.edu This comment highlights naturalistic observation as a specific method within Furr's (this issue) cluster direct behavioural observation and discusses the Electronically Activated Recorder (EAR) as a naturalistic observation sampling method that can be used in relatively large, nomothetic studies. Naturalistic observation with a method such as the EAR can inform researchers' understanding of personality in its relationship to daily behaviour in two important ways. It can help calibrate personality effects against act-frequencies of real-world behaviour and provide ecological, behavioural personality criteria that are independent of self-report. Copyright © 2009 John Wiley & Sons, Ltd. Measuring Behaviour D. S. MOSKOWITZ and JENNIFER J. RUSSELL Department of Psychology, McGill University, Montreal, Canada dsm@psych.mcgill.ca Furr (this issue) provides an illuminating comparison of the strengths and weaknesses of various methods for assessing behaviour. In the selection of a method for assessing behaviour, there should be a careful analysis of the definition of the behaviour and the purpose of assessment. This commentary clarifies and expands upon some points concerning the suitability of experience sampling measures, referred to as Intensive Repeated Measurements in Naturalistic Settings (IRM-NS). IRM-NS measures are particularly useful for constructing measures of differing levels of specificity or generality, for providing individual difference measures which can be associated with multiple layers of contextual variables, and for providing measures capable of reflecting variability and distributional features of behaviour. Copyright © 2009 John Wiley & Sons, Ltd. Behaviours, Non-Behaviours and Self-Reports SAMPO V. PAUNONEN Department of Psychology, University of Western Ontario, London, Canada paunonen@uwo.ca Furr's (this issue) thoughtful analysis of the contemporary body of research in personality psychology has led him to two conclusions: our science does not do enough to study real, observable behaviours; and, when it does, too often it relies on ,weak' methods based on retrospective self-reports of behaviour. In reply, I note that many researchers are interested in going beyond the study of individual behaviours to the behaviour trends embodied in personality traits; and the self-report of behaviour, using well-validated personality questionnaires, is often the best measurement option. Copyright © 2009 John Wiley & Sons, Ltd. An Ethological Perspective on How to Define and Study Behaviour LARS PENKE Department of Psychology, The University of Edinburgh, Edinburgh, UK lars.penke@ed.ac.uk While Furr (this issue) makes many important contributions to the study of behaviour, his definition of behaviour is somewhat questionable and also lacks a broader theoretical frame. I provide some historical and theoretical background on the study of behaviour in psychology and biology, from which I conclude that a general definition of behaviour might be out of reach. However, psychological research can gain from adding a functional perspective on behaviour in the tradition of Tinbergens's four questions, which takes long-term outcomes and fitness consequences of behaviours into account. Copyright © 2009 John Wiley & Sons, Ltd. What is a Behaviour? MARCO PERUGINI Faculty of Psychology, University of Milan,Bicocca, Milan, Italy marco.perugini@unimib.it The target paper proposes an interesting framework to classify behaviour as well as a convincing plea to use it more often in personality research. However, besides some potential issues in the definition of what is a behaviour, the application of the proposed definition to specific cases is at times inconsistent. I argue that this is because Furr attempts to provide a theory-free definition yet he implicitly uses theoretical considerations when applying the definition to specific cases. Copyright © 2009 John Wiley & Sons, Ltd. Is Personality Really the Study of Behaviour? MICHAEL D. ROBINSON Department of Psychology, North Dakota State University, Fargo, ND, USA Michael.D.Robinson@ndsu.edu Furr (this issue) contends that behavioural studies of personality are particularly important, have been under-appreciated, and should be privileged in the future. The present commentary instead suggests that personality psychology has more value as an integrative science rather than one that narrowly pursues a behavioural agenda. Cognition, emotion, motivation, the self-concept and the structure of personality are important topics regardless of their possible links to behaviour. Indeed, the ultimate goal of personality psychology is to understanding individual difference functioning broadly considered rather than behaviour narrowly considered. Copyright © 2009 John Wiley & Sons, Ltd. Linking Personality and Behaviour Based on Theory MANFRED SCHMITT Department of Psychology, University of Koblenz-Landau, Landau, Germany schmittm@uni-landau.de My comments on Furr's (this issue) target paper ,Personality as a Truly Behavioural Science' are meant to complement his behavioural taxonomy and sharpen some of the presumptions and conclusions of his analysis. First, I argue that the relevance of behaviour for our field depends on how we define personality. Second, I propose that every taxonomy of behaviour should be grounded in theory. The quality of behavioural data does not only depend on the validity of the measures we use. It also depends on how well behavioural data reflect theoretical assumptions on the causal factors and mechanisms that shape behaviour. Third, I suggest that the quality of personality theories, personality research and behavioural data will profit from ideas about the psychological processes and mechanisms that link personality and behaviour. Copyright © 2009 John Wiley & Sons, Ltd. The Apparent Objectivity of Behaviour is Illusory RYNE A. SHERMAN, CHRISTOPHER S. NAVE and DAVID C. FUNDER Department of Psychology, University of California, Riverside, CA, USA funder@ucr.edu It is often presumed that objective measures of behaviour (e.g. counts of the number of smiles) are more scientific than more subjective measures of behaviour (e.g. ratings of the degree to which a person behaved in a cheerful manner). We contend that the apparent objectivity of any behavioural measure is illusory. First, the reliability of more subjective measures of behaviour is often strikingly similar to the reliabilities of so-called objective measures. Further, a growing body of literature suggests that subjective measures of behaviour provide more valid measures of psychological constructs of interest. Copyright © 2009 John Wiley & Sons, Ltd. Personality and Behaviour: A Neglected Opportunity? LIAD UZIEL and ROY F. BAUMEISTER Department of Psychology, Florida State University, Tallahassee, FL, USA Baumeister@psy.fsu.edu Personality psychology has neglected the study of behaviour. Furr's efforts to provide a stricter definition of behaviour will not solve the problem, although they may be helpful in other ways. His articulation of various research strategies for studying behaviour will be more helpful for enabling personality psychology to contribute important insights and principles about behaviour. The neglect of behaviour may have roots in how personality psychologists define the mission of their field, but expanding that mission to encompass behaviour would be a positive step. Copyright © 2009 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||||||||||||||||||||||||||