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Selected AbstractsDownstream from calcium signalling: mitochondria, vacuoles and pancreatic acinar cell damageACTA PHYSIOLOGICA, Issue 1 2009S. Voronina Abstract Ca2+ is one of the most ancient and ubiquitous second messengers. Highly polarized pancreatic acinar cells serve as an important cellular model for studies of Ca2+ signalling and homeostasis. Downstream effects of Ca2+ signalling have been and continue to be an important research avenue. The primary functions regulated by Ca2+ in pancreatic acinar cells , exocytotic secretion and fluid secretion , have been defined and extensively characterized in the second part of the last century. The role of cytosolic Ca2+ in cellular pathology and the related question of the interplay between Ca2+ signalling and bioenergetics are important current research lines in our and other laboratories. Recent findings in these interwoven research areas are discussed in the current review. [source] Interpreting sustainable development and societal utility in Norwegian GMO assessmentsENVIRONMENTAL POLICY AND GOVERNANCE, Issue 4 2008G. Kristin Rosendal Abstract This article examines the process of assessing applications for genetically modified (GM) crops or plants for import or commercial planting in Norway. GMO legislation in Norway is closely linked to the EU through the Agreement on the European Economic Area (EEA), to which Norway is a party. A central difference with the EU processes emanates from specific clauses in the Norwegian Gene Technology Act on ,sustainable development' and ,societal utility', which provide a potentially wider leverage for Norwegian authorities to turn down the applications. Research material indicates evidence of an increasingly restrictive practice in the Norwegian evaluations, raising the question of how this can be explained in the face of increasing global acceptance of GMOs. A related question is to what extent and how this result is affected by the trends in the EU. An increasingly restrictive practice may be explained by changes in the access structure to the evaluating body, or it may be due to learning and a growing acceptance of the precautionary principle in this sector. Third, a higher number of rejections may largely be associated with the interest structure pertaining to GMOs in Norway. Final decisions are pending and there are uncertainties concerning how Norwegian authorities will apply the specific criteria of the Gene Technology Act. Copyright © 2008 John Wiley & Sons, Ltd and ERP Environment. [source] Genetic determinants of adult hippocampal neurogenesis correlate with acquisition, but not probe trial performance, in the water maze taskEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002G. Kempermann Abstract A number of reports have indicated that adult neurogenesis might be involved in hippocampal function. While increases in adult neurogenesis are paralleled by improvements on learning tasks and learning itself can promote the survival of newly generated neurons in the hippocampus, a causal link between learning processes and adult hippocampal neurogenesis is difficult to prove. Here, we addressed the related question of whether the baseline level of adult neurogenesis is predictive of performance on the water maze task as a test of hippocampal function. We used ten strains of recombinant inbred mice, based on C57BL/6, which are good learners and show high baseline levels of neurogenesis, and DBA/2, which are known to be poor learners and which exhibit low levels of adult neurogenesis. Two of these strains, BXD-2 and BXD-8, showed a 26-fold difference in the number of newly generated neurons per hippocampus. Over all strains, including the parental strains, there was a significant correlation between the number of new neurons generated in the dentate gyrus and parameters describing the acquisition of the water maze task (slope of the learning curves). Similar results were seen when the parental strains were not included in the analysis. There was no correlation between adult hippocampal neurogenesis and probe trial performance, performance on the rotarod, overall locomotor activity, and baseline serum corticosterone levels. This result supports the hypothesis that adult neurogenesis is involved in specific aspects of hippocampal function, particularly the acquisition of new information. [source] Resident and transient dynamics, site fidelity and survival in wintering Blackcaps Sylvia atricapilla: evidence from capture,recapture analysesIBIS, Issue 2 2007EDUARDO J. BELDA In their winter quarters, migrant birds may either remain within a small area (resident strategy) or move frequently over a large area looking for locally abundant food (transient strategy). It has been suggested that both strategies could simultaneously occur in the same population. We used time-since-marking capture,recapture models to infer the coexistence of these two behavioural strategies (transient and resident) among wintering Blackcaps Sylvia atricapilla using weekly recapture data over a 7-year period. A related question is whether Blackcaps, if surviving to the next winter, always return to the same wintering area, so we also used this approach to analyse winter site fidelity and to estimate annual survival probabilities. Model selection supported the existence of heterogeneity in survival estimates for both the within-season and the interannual survival probabilities, i.e. there was evidence for the existence of transients. It was estimated that 26% of the Blackcaps were resident during the winter. Mean apparent annual survival probability was 0.46 (se = ±0.11). However, there was some evidence suggesting that not all individuals showed winter site fidelity. The estimated proportion of individuals that, if alive, returned to the wintering area was 28%. This is the first study to show the existence of these two behavioural strategies (residence and transience) among wintering Blackcaps, and the first confirming this pattern using capture,recapture models. These models considering transient and resident dynamics may become an important tool with which to analyse wintering strategies. [source] Neural progenitor cells transplanted into the uninjured brain undergo targeted migration after stroke onsetJOURNAL OF NEUROSCIENCE RESEARCH, Issue 4 2008Raphael Guzman Abstract Endogenous neural stem cells normally reside in their niche, the subventricular zone, in the uninjured rodent brain. Upon stroke, these cells become more proliferative and migrate away from the subventricular zone into the surrounding parenchyma. It is not known whether this stroke-induced behavior is due to changes in the niche or introduction of attractive cues in the infarct zone, or both. A related question is how transplanted neural stem cells respond to subsequent insults, including whether exogenous stem cells have the plasticity to respond to subsequent injuries after engraftment. We addressed this issue by transplanting neural progenitor cells (NPCs) into the uninjured brain and then subjecting the animal to stroke. We were able to follow the transplanted NPCs in vivo by labeling them with superparamagnetic iron oxide particles and imaging them via high-resolution magnetic resonance imaging (MRI) during engraftment and subsequent to stroke. We find that transplanted NPCs that are latent can be activated in response to stroke and exhibit directional migration into the parenchyma, similar to endogenous neural NPCs, without a niche environment. © 2007 Wiley-Liss, Inc. [source] The evolution of bipedal postures in varanoid lizardsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 3 2009GORDON W. SCHUETT The bipedal posture (BP) and gait of humans are unique evolutionary hallmarks, but similar stances and forms of locomotion have had enormous influences on a range of phylogenetically diverse tetrapods, particularly dinosaurs and birds, and a range of mammalian lineages, including non-human apes. The complex movements involved in bipedalism appear to have modest evolutionary origins, and it is presumed that a stable and erect posture is a prerequisite for erect strides and other bipedal movements. Facultative bipedalism in several lineages of lizards is achieved by running, but some varanid lizards (genus Varanus) exhibit BPs without running. In these cases, BPs (BPstanding) are not used as a form of locomotion; rather, BPstanding is associated with defensive displays, and such postures also probably permit better inspection of the environment. Yet, in other varanids, BPs have been observed only during combat episodes (BPcombat), where both contestants rise together and embrace in the so-called clinch phase. Numerous other species, however, show neither type of BP. Past researchers have commented that only large-bodied varanids exhibit BP, a behaviour that appears to show phylogenetic trends. We termed this idea the King,Green,Pianka (KGP) bipedal hypothesis. In this article, we address two main questions derived from the KGP hypothesis. First, what is the phylogenetic distribution of BP in Varanus and close relatives (varanoids)? Second, is BP positively correlated with the phylogenetic distribution of large body size (e.g. snout,vent length, SVL)? In addition, we asked a related question: do the lengths of the femur and tail show body size-independent adaptive trends in association with BP? Because varanid species that show BPstanding also use these postures during combat (BPcombat), both types of BP were analysed collectively and simply termed BP. Using comparative phylogenetic analyses, the reconstruction of BP required three steps, involving a single gain and two losses. Specifically, BP was widespread in the monophyletic Varanus, and the single gain occurred at the most recent common ancestor of the African clade. The two losses of BP occurred in different clades (Indo-Asian B clade and Indo-Australian Odatria clade). BPs are absent in the sister group to Varanus (Lanthanotus borneensis) and the other outgroup species (Heloderma spp.). Our phylogenetic reconstruction supports the KGP prediction that BP is restricted to large-bodied taxa. Using the Hansen model of adaptive evolution on a limited, but highly relevant morphological dataset (i.e. SVL; femur length, FL; tail length, TL), we demonstrated that these characters were not equivalent in their contribution to the evolution of BP in Varanus. SVL was significantly correlated with BP when modelled in a phylogenetic context, but the model identified random processes as dominant over adaptive evolution, suggesting that a body size threshold might be involved in the evolution of BP. A Brownian motion (BM) model outperformed the selection model in our analysis of relative TL, suggesting that TL and BP evolved independently. The selection model for relative FL outperformed the BM model, indicating that FL and BP share an adaptive history. Our non-phylogenetic analyses involving regression residuals of FL and TL vs. SVL showed no significant correlation between these characters and BP. We suggest that BP in Varanus provides a convergent or analogue model from which to investigate various forms of bipedalism in tetrapod vertebrates, especially other reptiles, such as theropod dinosaurs. Because BPstanding in varanids is possibly an incipient stage to some form of upright locomotion, its inclusion as a general model in evolutionary analyses of bipedalism of vertebrates will probably provide novel and important insights. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 97, 652,663. [source] Bilinear modelling of batch processes.JOURNAL OF CHEMOMETRICS, Issue 5 2008Part I: theoretical discussion Abstract When studying the principal component analysis (PCA) or partial least squares (PLS) modelling of batch process data, one realizes that there is a wide range of approaches. In many cases, new modelling approaches are presented just because they work properly for a particular application, for example, on-line monitoring and a given number of processes. A clear understanding of why these approaches perform successfully and which are the advantages and disadvantages in front of the others is seldom supplied. Why does modelling after batch-wise unfolding capture changing dynamics? What are the consequences of variable-wise unfolding? Is there any best unfolding method? When should several models for a single process be used? In this paper, it is shown how these and other related questions can be answered by properly analyzing the dynamic covariance structures of the various approaches. Copyright © 2008 John Wiley & Sons, Ltd. [source] Common sense clarified: The role of intuitive knowledge in physics problem solvingJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 6 2006Bruce Sherin Over the last two decades, a significant body of research has documented the nature of intuitive physics knowledge,the knowledge of the world that students bring to the learning of formal physics. However, this research has yet to document the roles played by intuitive physics knowledge in expert physics practice. In this article, I discuss three related questions: (1) What role, if any, does intuitive knowledge play in physics problem solving? (2) How does intuitive physics knowledge change in order to play that role, if at all? (3) When and how do these changes typically occur? In answer to these questions, I attempt to show that intuitive physics knowledge can play a variety of roles in expert problem solving, including some roles that are central and directly connected to equations. This research draws on observations of college students working in pairs to solve physics problems. © 2006 Wiley Periodicals, Inc. J Res Sci Teach 43: 535,555, 2006 [source] THE CONTRIBUTION OF THIRD-PARTY INDICES IN ASSESSING GLOBAL OPERATIONAL RISKS;,JOURNAL OF SUPPLY CHAIN MANAGEMENT, Issue 4 2010KUNTAL BHATTACHARYYA In the face of global uncertainties and a growing reliance on third-party indices to obtain a snapshot of a country's operational risks, we explore the related questions: How accurately do third-party indices capture a country's operational risk, and how does the operational risk of the country, in turn, affect the volume of its import and export supply chains? We examine these questions by empirically investigating 81 member countries of the World Trade Organization (WTO) using archival data collected from UN agencies, independent think tanks, the WTO, and the Economist Intelligence Unit. We use seven third-party indices to gauge a country's internal environment and map those indices to corresponding country-specific operational risks to further understand the consequent effects of those operational risks on trading volume. Results provide strong evidence for the use of certain third-party indices in assessing operational risk. In addition, operational risks are found to negatively affect the volume of import and export supply chains, albeit in varying degrees. [source] Technology, security, and individual privacy: New tools, new threats, and new public perceptionsJOURNAL OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE AND TECHNOLOGY, Issue 3 2005Lee S. Strickland Highly portable information collection and transmission technologies such as radio frequency identification (RFID) tags and smart cards are becoming ubiquitous in government and business,employed in functions including homeland security, information security, physical premises security, and even the control of goods in commerce. And, directly or indirectly, in many of these applications, it is individuals and their activities that are tracked. Yet, a significant unknown is (a) whether the public understands these technologies and the manner in which personally identifiable information may be collected, maintained, used, and disseminated; and (b) whether the public consents to these information practices. To answer these and related questions, we surveyed a select group of citizens on the uses of this technology for business as well as homeland security purposes. We found a significant lack of understanding, a significant level of distrust even in the context of homeland security applications, and a very significant consensus for governmental regulation. We conclude that a primary objective for any organization deploying these technologies is the promulgation of a comprehensive Technology Privacy Policy, and we provide detailed specifications for such an effort. [source] Health Care in Rural TexasPOLICY STUDIES JOURNAL, Issue 1 2001William DeSoto The purpose of this article is to assess the quality of health and health care services available to rural Texans. Specifically, we seek to answer two related questions. First, do people living in rural areas of Texas generally suffer from poorer health than people living in urban Texas? One undoubtedly would think so, given frequent references to the low quality of personal services in general for rural America. Moreover, the persistence of the congressional Rural Health Care Caucus over the past two decades points to a rural health care crisis. Second, to what extent are these differences in health conditions explained by differences in access to health care enjoyed by people living in the two different regions? Access certainly appears to be the problem alluded to above. Rural people apparently lack physician care. In addition to providing answers to these questions, we also examine the difference in the health conditions and access to care enjoyed by minority and non-minority rural Texans. Is this a part of the rural health care problem given the high incidence of non-whites in rural Texas? If so this may be minority rather than rural neglect. We briefly conclude the article with some recommendations for improving the problems we identify. [source] Usability and effectiveness evaluation of a course-advising chat botPROCEEDINGS OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 1 2007Hyekyung Kim This research compares the usability and efficiency of a course-advising chat bot with menu driven FAQs (frequently asked questions). Based on a survey and user interviews, a text-based FAQ system was created and compared with a chat bot that was developed to address library and information science (LIS) graduate student course and program related questions. The students conducted tasks with both the chat bot and FAQ systems. The usability and effectiveness of the functionality and user-interface of both systems is assessed. [source] Into Cerberus' Lair: Bringing the Idea of Security to Light1BRITISH JOURNAL OF POLITICS & INTERNATIONAL RELATIONS, Issue 4 2005Graham M. Smith Using the motif of Cerberus, the three-headed monster watchdog of Hades, this article attempts to bring ,security' to light. Specifically, it addresses two related questions. The primary question is: What does ,security' mean?. Here it is argued that ,security' is related to ,order' and is a reflection not of a positive value in and of itself, but the relative success of any given order to realise its core values in relation to other orders. Therefore, ,security' is found to be like Cerberus insofar as it exists not as an independent value or being, but only in relation between two orders. Having located ,security' within this conceptual framework, the article then addresses its second question: What are the effects of security?. The motif of Cerberus suggests that security ,bites' in three ways: first, that specific measures of security control the members of an order; second, that the identification of security threats reinforce certain persons and structures of the order as being the definers of the order; and finally, that the implementation of certain security measures can change and transform the order itself. In this way the analysis offered here brings ,security' to light not only as an inherently political term connected to political values, but to provide foundations for critiquing the rhetorical use of ,security' in contemporary political discourse and thought. [source] Policy Change and the Politics of Ideas: The Emergence of the Canada/Quebec Pension PlansCANADIAN REVIEW OF SOCIOLOGY/REVUE CANADIENNE DE SOCIOLOGIE, Issue 3 2009KRISTINA BABICH Insistant sur l'impact direct des idées sur le changement politique, les auteurs se penchent sur l'adoption du Régime de rentes du Québec (RRQ) et du Régime de pensions du Canada (RPC) de 1965, en examinant deux questions étroitement liées: 1) Pourquoi le gouvernement fédéral a-t-il décidé de créer au milieu des années 1960 un système public de pension proportionnel aux revenus, en plus du Programme de la sécurité de la vieillesse alors en vigueur? et 2) Pourquoi ce nouveau système présente-t-il un taux de remplacement plus élevé que celui proposé initialement, de même qu'un régime différent pour le Québec? De manière à répondre à ces deux questions, les auteurs analysent les débats menant à l'adoption du RRQ et du RPC. Stressing the direct impact of ideas on policy change, this article explores the adoption of the Canada and Quebec Pension Plans (C/QPP) in 1965 by addressing two closely related questions: in the mid-1960s: why did the federal government decide to create an earnings-related public pension system on top of the existing Old Age Security program? Second, why did that new system feature a replacement rate higher than initially proposed as well as a separate scheme for the province of Quebec? In order to answer these two questions, the article analyzes the debates leading to the enactment of the C/QPP. [source] Cognitive Processes in Cognitive Therapy: Evaluation of the Mechanisms of Change in the Treatment of DepressionCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 3 2007Genevieve Garratt A central theoretical principle guiding cognitive therapy is that mediation by cognitive processes is linked to the successful treatment of depression. The most recent review of the literature on this question is over a decade old and was suggestive of cognitive mediation for cognitive therapy, but was not conclusive. Since this review, a number of studies have been published that address cognitive mediation. The mediation hypothesis can be broadly defined as encompassing two related questions: cognitive mediation framed as "are cognitive changes associated with therapeutic improvement," and cognitive specificity from the perspective of "are changes in cognition specific to cognitive therapy?" This latter question is particularly important when cognitive therapy is compared to pharmacotherapy. This article reviews the current literature associated with these questions. Our review indicates that the current body of research generally supports cognitive mediation, but is considerably more mixed for cognitive specificity. However, some evidence suggests that cognitive changes associated with pharmacotherapy are more superficial than those associated with cognitive therapy. [source] | |||||||||||||