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Selected AbstractsRoughness Characterization through 3D Textured Image Analysis: Contribution to the Study of Road Wear LevelCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 2 2004M. Khoudeir The microtexture is defined as surface irregularities whose height ranges from 0.001 mm to 0.5 mm and whose width is less than 0.5 mm (Alvarez and Mprel, 1994). The deterioration due to the road traffic, especially polishing effect, involves a change in the microtexture. So, we suggest a method to characterize, through image analysis, wear level or microroughness of road surfaces. We propose then, on one hand a photometric model for road surface, and, on the other hand, a geometrical model for road surface profile. These two models allow us to develop roughness criteria based on the study of the statistical properties of: the distribution of the gray levels in the image, the distribution of the absolute value of its gradient, the form of its autocorrelation function, and the distribution of its curvature map. Experiments have been done with images of laboratory-made road specimens at different wear levels. The obtained results are similar to those obtained by a direct method using road profiles. [source] A flexible content repository to enable a peer-to-peer-based wikiCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 7 2010Udo Bartlang Abstract Wikis,being major applications of the Web 2.0,are used for a large number of purposes, such as encyclopedias, project documentation, and coordination, both in open communities and in enterprises. At the application level, users are targeted as both consumers and producers of dynamic content. Yet, this kind of peer-to-peer (P2P) principle is not used at the technical level being still dominated by traditional client,server architectures. What lacks is a generic platform that combines the scalability of the P2P approach with, for example, a wiki's requirements for consistent content management in a highly concurrent environment. This paper presents a flexible content repository system that is intended to close the gap by using a hybrid P2P overlay to support scalable, fault-tolerant, consistent, and efficient data operations for the dynamic content of wikis. On the one hand, this paper introduces the generic, overall architecture of the content repository. On the other hand, it describes the major building blocks to enable P2P data management at the system's persistent storage layer, and how these may be used to implement a P2P-based wiki application: (i) a P2P back-end administrates a wiki's actual content resources. (ii) On top, P2P service groups act as indexing groups to implement a wiki's search index. Copyright © 2009 John Wiley & Sons, Ltd. [source] JAC: declarative Java concurrencyCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 5 2006Max Haustein Abstract The Java programming language has a low-level concurrency model which is hard to use and does not blend well with inheritance. JAC is an extension of Java that introduces a higher level of concurrency, hiding threads and separating thread synchronization from application logic in a declarative fashion. The emphasis is on limiting the differences between sequential and concurrent code, thus furthering code reuse, and on avoiding inheritance anomalies. This is achieved by taking a middle road between concurrent code on the one hand and complete separation of sequential application logic from concurrency mechanisms on the other. An extensive comparison with related approaches is given for motivating our design decisions. Copyright © 2005 John Wiley & Sons, Ltd. [source] Crystallization kinetics of ZnS precipitation; an experimental study using the mixed-suspension-mixed-product-removal (MSMPR) methodCRYSTAL RESEARCH AND TECHNOLOGY, Issue 8 2004Mousa Al-Tarazi Abstract The precipitation kinetics of zinc sulfide were studied using a lab scale mixed-suspension-mixed-product-removal (MSMPR) precipitation reactor. The vessel was operated at different feed concentrations, molar ratios, stirrer speeds, pH-values, feed injection positions and residence times. Primary nucleation and volume average crystal growth rates as well as agglomeration kernel were determined. Relationships were found between the rates of the different crystallization steps on the one hand and supersaturation, stirrer speeds, pH-values, Zn2+ to S2- ratio, feed positions on the other. These show that larger crystals are obtained at high supersaturation, moderate stirrer speeds, small residence times, a pH-value of around 5 and high Zn2+ to S2- ratios. One should realize though that the applied MSMPR method is not the most optimal technique for examining fast precipitation reactions. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] GOOD GIFTS FOR THE COMMON GOOD: Blood and Bioethics in the Market of Genetic ResearchCULTURAL ANTHROPOLOGY, Issue 3 2007DEEPA S. REDDY This article is based on ethnographic fieldwork conducted with the Indian community in Houston, as part of a NIH,NHGRI-sponsored ethics study and sample collection initiative entitled "Indian and Hindu Perspectives on Genetic Variation Research." At the heart of this research is one central exchange,blood samples donated for genetic research,that draws both the Indian community and a community of researchers into an encounter with bioethics. I consider the meanings that come to be associated with blood donation as it passes through various hands, agendas, and associated ethical filters on its way to the lab bench: how and why blood is solicited, how the giving and taking of blood is rationalized, how blood as material substance is alienated, processed, documented, and made available for the promised ends of basic science research. Examining corporeal substances and asking what sorts of gifts and problems these represent, I argue, sheds some light on two imbricated tensions expressed by a community of Indians, on the one hand, and of geneticists and basic science researchers, on the other hand: that gifts ought to be free (but are not), and that science ought to be pure (but is not). In this article, I explore how experiences of bioethics are variously shaped by the histories and habits of Indic giving, prior sample collection controversies, commitments to "good science" and the common "good of humanity," and negotiations of the sites where research findings circulate. [source] Cervical screening: how often should women be screened?CYTOPATHOLOGY, Issue 2 2000A. Herbert Introduction As a result of major improvements that have been made to cervical screening during the last 15 years, and implementation of call and recall to invite all women aged 20,64 for screening, the incidence of cervical carcinoma has fallen by 42% since 19901. Cervical cancer is now a rare disease, largely thanks to the widespread uptake of screening by the women at risk. Despite the manifest success of the NHS Cervical Screening Programme (NHSCSP), there is pressure on one hand to improve its sensitivity by the introduction of new technology, including human papillomavirus (HPV) testing2, and on the other hand to reduce the cost of the programme, which is more than £130m per year. The main method suggested to reduce costs is the restriction of routine screening to an interval of 5 years3,5. [source] Causal mapping as a tool to mechanistically interpret phenomena in cell motility: Application to cortical oscillations in spreading cellsCYTOSKELETON, Issue 9 2006Gabriel E. Weinreb Abstract Biological processes that occur at the cellular level and consist of large numbers of interacting elements are highly nonlinear and generally involve multiple time and spatial scales. The quantitative description of these complex systems is of great importance but presents large challenges. We outline a new systems biology approach, causal mapping (CMAP), which is a coarse-grained biological network tool that permits description of causal interactions between the elements of the network and overall system dynamics. On one hand, the CMAP is an intermediate between experiments and physical modeling, describing major requisite elements, their interactions and paths of causality propagation. On the other hand, the CMAP is an independent tool to explore the hierarchical organization of cell and the role of uncertainties in the system. It appears to be a promising easy-to-use technique for cell biologists to systematically probe verbally formulated qualitative hypotheses. We apply the CMAP to study the phenomenon of contractility oscillations in spreading cells in which microtubules have been depolymerized. The precise mechanism by which these oscillations are governed by a complex mechano-chemical system is not known but the data observed in experiments can be described by a CMAP. The CMAP suggests that the source of the oscillations results from the opposing effects of Rho activation leading to a decreased level of myosin light chain phosphatase and a cyclic calcium influx caused by increased membrane tension and leading to a periodically enhanced activation of myosin light chain kinase. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Emotional processing in eating disorders: specific impairment or general distress related deficiency?DEPRESSION AND ANXIETY, Issue 6 2006Eva Gilboa-Schechtman Ph.D. Abstract The literature on eating disorders emphasizes the relationship between alexithymia and anorexia nervosa on the one hand, and between bulimia nervosa and affect dysregulation on the other. In our study, two questions are addressed: (1) Are there different patterns of emotional processing deficiencies in anorexia and bulimia? and (2) Is there a unique contribution of eating disorders to emotional processing deficiencies? Participants were women with anorexia nervosa (ANs, n=20), bulimia nervosa (BNs, n=20), and normal controls (NCs, n=20). Three hypotheses were examined: (1) Women with eating disorders will exhibit lower emotional awareness and more deficient emotional regulation than will NCs (emotional deficiency); (2) ANs will be less emotionally aware than BNs, whereas BNs will be less capable of effective emotional regulation than ANs (disorder specificity); and (3) emotional distress will mediate the relationships between emotional processing and eating disorders (emotional distress mediation). Results supported the emotional deficiency and distress mediation hypotheses, and partially supported the disorder specificity hypothesis. The need to move beyond alexithymia in understanding the pattern of emotional processing deficiencies in eating disorders is discussed. Depression and Anxiety 23:331,339, 2006. © 2006 Wiley-Liss, Inc. [source] Brain mechanisms underlying emotional alterations in the peripartum period in ratsDEPRESSION AND ANXIETY, Issue 3 2003Inga D. Neumann Abstract In the period before and after parturition, i.e., in pregnancy and lactation, a variety of neuroendocrine alterations occur that are accompanied by marked behavioral changes, including emotional responsiveness to external challenging situations. On the one hand, activation of neuroendocrine systems (oxytocin, prolactin) ensures reproduction-related physiological processes, but in a synergistic manner also ensures accompanying behaviors necessary for the survival of the offspring. On the other hand, there is a dramatic reduction in the responsiveness of neuroendocrine systems to stimuli not relevant for reproduction, such as the hypothalamo-pituitary-adrenal (HPA) axis responses to physical or emotional stimuli in both pregnant and lactating rats. With CRH being the main regulator of the HPA axis, downregulation of the brain CRH system may result in various behavioral, in particular emotional, adaptations of the maternal organisms, including changes in anxiety-related behavior. In support of this, the lactating rat becomes less emotionally responsive to novel situations, demonstrating reduced anxiety, and shows a higher degree of aggressive behavior in the test for agonistic behavior as well as in the maternal defense test. These changes in emotionality are independent of the innate (pre-lactation) level of anxiety and are seen in both rats bred for high as well as low levels of anxiety. Both brain oxytocin and prolactin, highly activated at this time, play a significant role in these behavioral and possibly also neuroendocrine adaptations in the peripartum period. Depression and Anxiety 17:111,121, 2003. © 2003 Wiley-Liss, Inc. [source] How does premenstrual dysphoric disorder relate to depression and anxiety disorders?DEPRESSION AND ANXIETY, Issue 3 2003Mikael Landén M.D., Ph.D. Abstract Premenstrual dysphoric disorder (PMDD) is a severe variant of premenstrual syndrome that afflicts approximately 5% of all women of fertile age. The hallmark of this condition is the surfacing of symptoms during the luteal phase of the menstrual cycle, and the disappearance of symptoms shortly after the onset of menstruation. Whereas many researchers have emphasized the similarities between PMDD and anxiety disorders, and in particular panic disorder, others have suggested that PMDD should be regarded as a variant of depression. Supporting both these notions, the treatment of choice for PMDD, the serotonin reuptake inhibitors (SRIs), is also first line of treatment for depression and for most anxiety disorders. In this review, the relationship between PMDD on the one hand, and anxiety and depression on the other, is being discussed. Our conclusion is that PMDD is neither a variant of depression nor an anxiety disorder, but a distinct diagnostic entity, with irritability and affect lability rather than depressed mood or anxiety as most characteristic features. The clinical profile of SRIs when used for PMDD, including a short onset of action, suggests that this effect is mediated by other serotonergic synapses than the antidepressant and anti-anxiety effects of these drugs. Although we hence suggest that PMDD should be regarded as a distinct entity, it should be emphasized that this disorder does display intriguing similarities with other conditions, and in particular with panic disorder, which should be the subject of further studies. Also, the possibility that there are subtypes of PMDD more closely related to depression, or anxiety disorders, than the most common form of the syndrome, should not be excluded. Depression and Anxiety 17:122,129, 2003. © 2003 Wiley-Liss, Inc. [source] Foreign Direct Investment in the CaribbeanDEVELOPMENT POLICY REVIEW, Issue 1 2008Ivar Kolstad This article addresses the question of whether the Caribbean is particularly attractive or unattractive to foreign investors, and if it has specific characteristics that attract or deter FDI. An econometric analysis of data from 135 countries for 1980-2002 shows that the Caribbean does not suffer from low inflows of FDI; on the contrary, Caribbean countries receive more FDI than comparable countries in other regions. This reflects two contradictory effects. On the one hand, FDI inflows may be particularly sensitive to political instability in the region; on the other hand, the absence of regulation appears to have been a particularly beneficial factor in attracting FDI to the Caribbean. [source] The Machakos Case Study: Solid Outcomes, Unhelpful HyperboleDEVELOPMENT POLICY REVIEW, Issue 1 2006Jules Siedenburg This article revisits the well-known study of Machakos District, Kenya reported in the book More People, Less Erosion by Tiffen et al., which found dramatic, compelling evidence of successful endogenous adaptation to changing circumstances by rural Africans. The article seeks to elucidate discrepancies between the Machakos findings and other findings in the interest of both scientific accuracy and policy relevance. It is suggested that the Machakos study comprises hopeful data, on the one hand, and problematic calculations and assertions, on the other. After exploring problems with the study, the article suggests an alternative interpretation of the data that is arguably more pertinent to contemporary concerns with rural poverty and environmental degradation as well as more widely applicable in sub-Saharan Africa. [source] Social Protection: Defining the Field of Action and PolicyDEVELOPMENT POLICY REVIEW, Issue 5 2002Andy Norton This article reviews recent developments in the concept of social protection, beginning with an attempt to establish a working definition of the term. This is set in the context of globalisation and new thinking on connections between the management of vulnerability, risk and poverty on the one hand and long,term economic and social development on the other. The article identifies aspects of the debate which require further development, by exploring the relationship between social protection, equality, social cohesion and rights. It also reviews contemporary definitions of social protection in the policies of donors and international organisations, and summarises lessons to be learnt from experience to date with civil society practices and state policies in the developing world. [source] Ataxia, autism, and the cerebellum: a clinical study of 32 individuals with congenital ataxiaDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2005Ingegerd Åhsgren MD The suggested link between autism and cerebellar dysfunction formed the background for a Swedish clinical study in 2001. Thirty-two children (17 females, 15 males; mean age 12y, SD 3y 10mo; range 6 to 21y) with a clinical suspicion of non-progressive congenital ataxia were examined, and parents were interviewed about the presence of neuropsychiatric problems in the child. Twelve children had simple ataxia, eight had ataxic diplegia, and 12 had,borderline'ataxia. All but one of the 32 children had a mild to moderate gross motor disability according to Gross Motor Function Classification System (15 were categorized as level I,16 as level II, and one child as level IV). Neuroimaging and neuropsychological testing were achieved in most cases. There was a strong association between learning disability* and autism spectrum disorder (often combined with hyperactivity disorder) on the one hand, and both simple and borderline,ataxia'on the other, but a weaker link between ataxic diplegia and neuropsychiatric disorders. A correlation between cerebellar macropathology on neuroimaging and neuropsychiatric disorders was not supported. Congenital ataxia might not be a clear-cut syndrome of cerebellar disease, but one of many signs of prenatal events or syndromes, leading to a complex neurodevelopmental disorder including autism and learning disability. [source] Effects and serum levels of glibenclamide and its active metabolites in patients with type 2 diabetesDIABETES OBESITY & METABOLISM, Issue 6 2001A. Jönsson SUMMARY Objective To study the effects and serum levels of glibenclamide (Gb) and its active metabolites in patients on chronic Gb medication on different daily doses. Material and methods Fifty patients with type 2 diabetes on regular Gb therapy (1.75,14.0 mg daily). Blood samples were taken immediately before and 90 min after regular Gb intake. A standardized breakfast was served 30 min after drug intake. Serum insulin and proinsulin levels were determined by ELISA methods without cross-reactivities. Serum drug levels were determined by HPLC. Fischer's R to Z -test (correlation coefficients) and paired Student t -tests were used when comparing values within the entire group and unpaired non-parametric Mann,Whitney tests were used when comparing high and low dose levels. A p-value <,0.05 was considered significant. Results There were significant correlations between daily Gb dose, on the one hand, and, on the other, HbAlc (r = 0.55), ,-insulin (r = , 0.59) and ,-proinsulin (r = , 0.52) levels. Significant correlations between Gb therapy duration and insulin (r = , 0.40) and proinsulin (r = , 0.34) secretion and between Gb dose and ratio proinsulin/insulin (RPI) at both time points (r = 0.32 and 0.30) were also found. The RPI was lower after Gb intake. In patients on , 10.5 mg steady state serum metabolite levels (Ml and Ml + M2) were higher (29(0,120) and 33 (0,120) ng/ml) than those of Gb itself (18(0,64) ng/ml). A great inter-subject variability in Gb levels at both time points was seen. Conclusions Our results indicate that, in patients on chronic medication, Gb is capable of stimulating both insulin and proinsulin secretion; the effect on insulin release is relatively greater. The effect was more pronounced in patients on a low Gb dose, either because of less impaired ,-cells in those receiving low doses, or due to reduced sulphonylurea sensitivity in those on high dosage (down-regulation). In patients on a daily dose of 10.5 mg or more, serum metabolite levels of clinical relevance were demonstrated; the metabolites may contribute to hypoglycaemic events. [source] Measuring aggression with the staff observation aggression scale , revisedACTA PSYCHIATRICA SCANDINAVICA, Issue 2002H. Nijman Objective:, The staff observation aggression scale (SOAS; Palmstierna & Wistedt, 1987) was developed to measure nature, number, as well as severity of aggressive incidents. In 1999, a revised version of the SOAS (i.e. the SOAS-R), with a more fine-grained severity scoring system, was presented. In the current paper, the development and testing of the revised severity scores of the SOAS-R are addressed. Method: In two consecutive studies, staff members recorded inpatient aggression on SOAS-R forms, but also expressed their opinion about the severity of incidents on 100 mm visual analogue scales (VASs). Correlations were calculated between SOAS and SOAS-R severity scores, on the one hand, and clinical judgements of severity, on the other. Results:, In both studies, revised SOAS severity scores were more closely related to clinical judgements of aggression severity than the original ones. Conclusion: The SOAS-R is a promising tool for research on the prevalence, severity and determinants of inpatient aggression. [source] Belief-Independent Processes and the Generality Problem for ReliabilismDIALECTICA, Issue 1 2005Mark McEvoy The Generality Problem for process reliabilism is to outline a procedure for determining when two beliefs are produced by the same process, in such a way as to avoid, on the one hand, individuating process types so narrowly that each type is instantiated only once, or, on the other hand, individuating them so broadly that beliefs that have different epistemic statuses are subsumed under the same process type. In this paper, I offer a solution to the problem which takes belief-independent processes to be functions that take as inputs information about distal states of affairs, and produce beliefs as outputs. Processes are individuated narrowly, so as to avoid the latter aspect of the Generality problem, but, by holding process tokens to be of the same type when they take perceptually equivalent scenes as inputs, and produce beliefs of the same kind as outputs, the former aspect of the problem is avoided too. Having argued that this method of typing process tokens solves the Generality Problem, I then argue that my solution does not fall prey to objections that have been, or might be, raised for similar proposals. [source] Speaking of God after the Death of GodDIALOG, Issue 3 2005By Daniel J. Peterson Abstract:, This article affirms the ability to talk about God in the twenty-first century 40 years after God died (according to Death-of-God theologians) in the 1960s. It does so by an appeal to the proper combination of mystery and revelation ideally expressed in the paradox that God reveals Godself as hidden. The language of God's revealed hiddenness comprises a "middle way" which avoids the extremes of theological hubris on the one hand and atheism or unbelief on the other, making it possible to speak today of God in a faithful yet humble manner. [source] Constructing a Christian PolydoxyDIALOG, Issue 4 2001Gary Pence In another article in this issue of Dialogmy colleague Stephen Ellingson usefully summarizes social science findings about the character of spirituality and religious belief and practice among young adults in the United States today. Especially characteristic of their emerging consciousness, he notes, is the separation between personal spirituality and organized, official, institutionalized religion, on the one hand, and their "re,grounding of religious authority in experience and practice instead of in belief and doctrine," on the other. Although Ellingson sees both "problems and possibilities" in the new forms of spirituality that he describes, he focuses on "the theological and ecclesiological challenges posed by the new religious context." In this article I will explore their positive possibilities. [source] Curricular Planning along the Fault Line between Instrumental and Academic Agendas: A Response to the Report of the Modern Language Association on Foreign Languages and Higher Education: New Structures for a Changed World,DIE UNTERRICHTSPRAXIS/TEACHING GERMAN, Issue 2 2009Ingeborg Walther In calling for new governance structures and unified curricula, the MLA Report distinguishes between instrumental and constitutive views of language that characterize our often schizophrenic agendas of language acquisition on the one hand, and disciplinary knowledge on the other. This paper explores some common theoretical insights from the fields of language acquisition and cultural studies that interrogate these views, providing a basis for sustained collaboration around curricula among faculty on both sides of the divide. While these have already yielded the kinds of curricular innovations recommended by the Report, a case is made for more radical changes in hiring practices, distribution of teaching and service, reward structures, and graduate education , changes which have the capacity to transform the institutional values upon which they will also depend. [source] Constructing Vulnerability: The Historical, Natural and Social Generation of Flooding in Metropolitan ManilaDISASTERS, Issue 3 2003Greg Bankoff Flooding is not a recent hazard in the Philippines but one that has occurred throughout the recorded history of the archipelago. On the one hand, it is related to a wider global ecological crisis to do with climatic change and rising sea levels but on the other hand, it is also the effect of more localised human activities. A whole range of socio-economic factors such as land use practices, living standards and policy responses are increasingly influencing the frequency of natural hazards such as floods and the corresponding occurrence of disasters. In particular, the reason why flooding has come to pose such a pervasive risk to the residents of metropolitan Manila has its basis in a complex mix of inter-relating factors that emphasise how the nature of vulnerability is constructed through the lack of mutuality between environment and human activity over time. This paper examines three aspects of this flooding: first, the importance of an historical approach in understanding how hazards are generated; second, the degree of interplay between environment and society in creating risk; and third, the manner in which vulnerability is a complex construction. [source] Internal Displacement in BurmaDISASTERS, Issue 3 2000Steven Lanjouw The internal displacement of populations in Burma is not a new phenomenon. Displacement is caused by numerous factors. Not all of it is due to outright violence, but much is a consequence of misguided social and economic development initiatives. Efforts to consolidate the state by assimilating populations in government-controlled areas by military authorities on the one hand, while brokering cease-fires with non-state actors on the other, has uprooted civilian populations throughout the country. Very few areas in which internally displaced persons (IDPs) are found are not facing social turmoil within a climate of impunity. Humanitarian access to IDP populations remains extremely problematic. While relatively little information has been collected, assistance has been focused on targeting accessible groups. International concern within Burma has couched the problems of displacement within general development modalities, while international attention along its borders has sought to contain displacement. With the exception of several recent initiatives, few approaches have gone beyond assistance and engaged in the prevention or protection of the displaced. [source] Leading science: staying informed without micromanaging (achieving and keeping the balance)DRUG DEVELOPMENT RESEARCH, Issue 2 2005Alice M. Sapienza Abstract Those who lead scientific efforts understand that they must contribute to judgments of both value and meaning of new data emerging from the bench. However, there is a fine line between staying informed, on the one hand, and quashing morale and creativity by overmanaging scientists at the bench. We discuss why we believe that micromanagement may be more likely to occur in science and how it can impact the caliber of scientific output. We also provide guidelines for how leaders can move with the data appropriately and keep the balance between staying abreast of work versus putting the brakes on work. Drug Dev. Res. 64:99,104, 2005. © 2005 Wiley-Liss, Inc. [source] What shapes Eurasian lynx distribution in human dominated landscapes: selecting prey or avoiding people?ECOGRAPHY, Issue 4 2009Mathieu Basille In the multi-use landscape of southern Norway, the distribution of lynx is likely to be determined both by the abundance of their favoured prey , the roe deer , and the risk associated with the presence of humans because most lynx mortalities are caused by humans (recreational harvest, poaching, vehicle collisions). We described the distribution of the reproductive portion of the lynx population based on snow-track observations of females with dependent kittens collected over 10,yr (1997,2006) in southern Norway. We used the ecological-niche factor analysis to examine how lynx distribution was influenced by roe deer, human activity, habitat type, environmental productivity and elevation. Our first prediction that lynx should be found in areas of relatively high roe deer abundance was supported. However, our second prediction that lynx should avoid human activity was rejected, and lynx instead occupied areas more disturbed in average than those available (with the exception of the most densely occupied areas). Lynx, however, avoided the most disturbed areas and our third prediction of a trade-off between abundance of prey and avoidance of human activity was supported. On the one hand, roe deer in the most disturbed areas benefit to a large extent from current human land use practices, potentially allowing them to escape predation from lynx. On the other hand, the situation is not so favourable for the predators who are restricted in competition refuges with medium to low prey densities. The consequence is that lynx conservation will have to be achieved in a human modifed environment where the potential for a range of conflicts and high human-caused mortality will remain a constant threat. [source] Response of collembolan communities to land-use change and grassland successionECOGRAPHY, Issue 2 2007Matthieu Chauvat This study focuses on the long-term changes of collembolan communities occurring after the conversion of arable land to managed grassland. We analysed collembolan communities at grassland sites of different age that had been gradually converted over a period of 50 yr. Abundance and biomass responded rapidly and very positively to the conversion of arable land to grassland, while species richness was not affected. Collembolan assemblages changed only little during grassland maturation. The impact of land-use change on community structure was more obvious at the functional level because the colonization processes observed in our study mostly relied on hemiedaphic species. Vegetation and soil parameters were good predictors of collembolan community structure during development of managed grassland. The present study demonstrated that past landscape patterns and processes like land-use conversion and subsequent succession had a considerable impact on the present day pattern of species richness and community composition of Collembola within a landscape. Our results strongly differ from those obtained for other invertebrate groups, highlighting on the one hand the very diverse reactions of invertebrates to a common factor, and on the other hand the need to survey more than one taxa in order to draw conclusions on effects of land-use change on faunistic communities. [source] Seed weevils living on the edge: pressures and conflicts over body size in the endoparasitic Curculio larvaeECOLOGICAL ENTOMOLOGY, Issue 3 2009RAÚL BONAL Abstract 1.,Body size in parasitic insects can be subjected to contrasting selective pressures, especially if they complete their development within a single host. On the one hand, a larger body size is associated with a higher fitness. On the other hand, the host offers a discrete amount of resources, thus constraining the evolution of a disproportionate body size. 2.,The present study used the weevil Curculio elephas as a study model. Larvae develop within a single acorn, feeding on its cotyledons, and larval body size is strongly related to individual fitness. 3.,The relationship between larval and acorn size was negatively exponential. Larval growth was constrained in small acorns, which did not provide enough food for the weevils to attain their potential size. Larval size increased and levelled off in acorns over a certain size (inflexion point), in which cotyledons were rarely depleted. When there were more than one larva per acorn, a larger acorn was necessary to avoid food depletion. 4.,The results show that C. elephas larvae are sometimes endoparasitic, living on the edge of host holding capacity. If they were smaller they could avoid food depletion more easily, but the fitness benefits linked to a larger size have probably promoted body size increase. The strong negative effects of conspecific competition may have possibly influenced female strategy of laying a single egg per seed. 5.,Being larger and fitter, but always within the limits of the available host sizes, may be one main evolutionary dilemma in endoparasites. [source] Thrips see red , flower colour and the host relationships of a polyphagous anthophilic thripsECOLOGICAL ENTOMOLOGY, Issue 5 2007A. YAKU Abstract 1.,The common blossom thrips, Frankliniella schultzei, is a polyphagous anthophilic species that colonises a wide range of host-plant species across different plant taxa. The environmental cues used by these polyphagous insects to recognise and locate host plants are not known. We therefore determined if colour is an important environmental signal used by F. schultzei to recognise flowers of eight of its more significant host-plant species. 2.,The effect of flower colour on the colonisation of different host plant species by F. schultzei was investigated by collecting and analysing the following: (a) numbers of thrips from different heights and aspects of the primary host plant Malvaviscus arboreus, (b) thrips distribution within flowers of Hibiscus rosasinensis, (c) colour reflectance from flowers of eight different host-plant species, and (d) reflectance from different coloured sticky traps and the number of thrips trapped on them at different times of the day and on different dates. 3.,The results indicate that: (a) the thrips (both sexes) concentrate towards the top of the primary host plant M. arboreus and are not distributed differentially according to sunny or shady aspect of the plant, (b) the number of female thrips on H. rosasinensis was higher in anthers compared to petals (corolla) and the basal parts of the flower, and males were as numerous on the petals as were females, and (c) there is a common floral reflectance pattern (but with different intensities) across the eight host plant species, mainly in the red part of the spectrum (600,700 nm). 4.,Results of colour sticky trapping show that red attracts more female thrips compared to any other colour and that most were caught between 09.00 and 11.00 hours. By contrast, more male thrips were trapped between 07.00 and 09.00 hours. Males were more evenly distributed across the different colours but the highest numbers were associated with the yellow traps. 5.,The higher densities of thrips at the top of their host plant may be related to the early morning (07.00,11.00 hours) activity of the thrips, when the top portions of the plant are more exposed to sunlight. The sex-related distributions of F. schultzei thrips across time, coloured sticky traps, and various parts of the flowers seem to be related to mating swarm formation by the males, on the one hand, and the relative frequency and intensity of the use of M. arboreus by the females, on the other, as a feeding and oviposition site. Frankliniella schultzei females respond more strongly to red than to any other colours, so it is predicted that the spectral properties of colour recognition by this species will correlate with the predominant red reflectance of its primary host, M. arboreus, and that there may well be a sex-related difference in colour recognition within this species. [source] University of Michigan Addiction Research Center (UMARC): development, evolution, and directionADDICTION, Issue 6 2010Robert A. Zucker ABSTRACT A historical summary is provided of the evolution of the University of Michigan Addiction Research Center (UMARC) since its origins in 1988. Begun as an National Institutes of Health (NIH) research center within a Department of Psychiatry and focused solely upon alcohol and aging, early work emphasized treatment efficacy, differential outcome studies and characterization of the neurophysiological and behavioral manifestations of chronic alcoholism. Over the last 15 years, UMARC has extended its research focus along a number of dimensions: its developmental reach has been extended etiologically by studies of risk early in the life span, and by way of work on earlier screening and the development of early, brief treatment interventions. The addiction focus has expanded to include other drugs of abuse. Levels of analysis have also broadened, with work on the molecular genetics and brain neurophysiology underlying addictive processes, on one hand, and examination of the role of the social environment in long-term course of disorder on the other hand. Activities have been facilitated by several research training programs and by collaborative relationships with other universities around the United States and in Poland. Since 2002, a program for research infrastructure development and collaboration has been ongoing, initially with Poland and more recently with Ukraine, Latvia and Slovakia. A blueprint for the future includes expanded characterization of the neurobiology and genetics of addictive processes, the developmental environment, as well as programmatic work to address the public health implications of our ability to identify risk for disorder very early in life. [source] Trust, Transactions, and Information Technologies in the U.S. Logistics IndustryECONOMIC GEOGRAPHY, Issue 2 2007Yuko Aoyama Abstract: How does information technology (IT) alter the organizational dynamics in an industry? In this article, we examine changes in competition and interfirm relations in the U.S. logistics industry, particularly whether "trust-based" interfirm relationships are being substituted by "competition-based" relationships and the rationale for outsourcing. We also examine how new IT tools and outsourcing interact and how logistics contracts, the size of firms, and knowledge lead to integration or disintegration within the industry. The results of our research demonstrate that while the use of IT tools is widespread, traditional trust-based relationships exhibit a considerable resilience in the logistics industry. The industry is also undergoing a complex process of restructuring in response to technological change, on the one hand, and the persistence of geographic and functional specialization, on the other hand. The industry's focus on the delivery of high-quality services, coupled with excess capacity in the industry in the past few years, has contributed to these contradictory trends. As a result, elimination of the middleman has not been as widely observed as expected. [source] Capital Versus the Districts: A Tale of One Multinational Company's Attempt to Disembed ItselfECONOMIC GEOGRAPHY, Issue 2 2004N. A. Phelps Abstract: The process of international economic integration in which multinational enterprises (MNEs) play a significant orchestrating role is a contradictory one of a space of flows, on the one hand, and a space of places, on the other hand. It is this contradiction that produces a variegated landscape of relations within and among MNEs and a whole range of territorially rooted organizations and institutions. As a result, interest in global production networks, as part of a broader relational turn in economic geography, has sought to highlight and uncover these webs of relations within which MNEs are embedded. In reviewing this literature, we emphasize the economic imperatives underlying such relations or, rather, their political-economic nature and the discontinuities in industrial restructuring they can produce. We then present an empirical illustration of these points and some of the key concerns within the literature on global production networks. We consider a recent round of restructuring by Black & Decker Corporation, focusing on the politico-economic ramifications of closing one of two European factories. Our reading of the literature, coupled with our empirical findings, suggests the continuing tendency for international integration as a space of flows to eclipse the coherence of places. Localized points of resistance can moderate the powers exercised by MNEs internally and across a network of organizations, although there are limits to the transferability of such tactics of resistance. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||