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Major Aspects (major + aspect)
Selected AbstractsPlatelet hyperreactivity generalizes to multiple forms of stimulationJOURNAL OF THROMBOSIS AND HAEMOSTASIS, Issue 9 2006D. L. YEE Summary.,Background:,Although platelet hyperreactivity constitutes an important cardiovascular risk factor, standardized methods for its measurement are lacking. We recently reported that aggregometry using a submaximal concentration of epinephrine identifies individuals with in vitro platelet hyperreactivity; this hyperreactivity was reproducible on multiple occasions over long periods of time. Objective and methods:,To better understand this aberrant reactivity, we studied in a large group of subjects (n = 386) the relationship between healthy individuals' platelet reactivity to epinephrine and their platelet phenotype as measured by other functional assays. Results:,Subjects with hyperreactivity to epinephrine were more likely to exhibit hyperfunction in each major aspect of platelet activity, including adhesion (response to low-dose ristocetin; P < 0.001), activation (surface P-selectin expression and PAC-1 binding after stimulation; P , 0.003) and aggregation to other agonists [no agonist, adenosine diphosphate (ADP), arachidonic acid, collagen, collagen-related peptide and ristocetin; P , 0.025] and to applied shear stress (PFA-100 and cone-and-plate viscometer; P < 0.05). These differences persisted after adjusting for demographic and hematologic differences between groups. We studied candidate genes relevant to epinephrine-mediated platelet activation and found that hyperreactivity to epinephrine was associated with a polymorphism on the gene (GNB3) encoding the beta-3 subunit of G proteins (P = 0.03). Conclusions:,Robust aggregation to a submaximal concentration of epinephrine establishes a true hyperreactive platelet phenotype that is ,global' as opposed to agonist specific; detection of this phenotype could be useful for studying patients at risk for arterial thrombosis. The mechanisms underlying hyperreactivity to different types of platelet stimulation may share common signaling pathways, some of which may involve specific G protein subunits. [source] Molecular identification of some forensically important blowflies of southern Africa and AustraliaMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2003M. L. Harvey Abstract., One major aspect of research in forensic entomology is the investigation of molecular techniques for the accurate identification of insects. Studies to date have addressed the corpse fauna of many geographical regions, but generally neglected the southern African calliphorid species. In this study, forensically significant calliphorids from South Africa, Swaziland, Botswana and Zimbabwe and Australia were sequenced over an 1167 base pair region of the COI gene. Phylogenetic analysis was performed to examine the ability of the region to resolve species identities and taxonomic relationships between species. Analyses by neighbour-joining, maximum parsimony and maximum likelihood methods all showed the potential of this region to provide the necessary species-level identifications for application to post-mortem interval (PMI) estimation; however, higher level taxonomic relationships did vary according to method of analysis. Intraspecific variation was also considered in relation to determining suitable maximum levels of variation to be expected during analysis. Individuals of some species in the study represented populations from both South Africa and the east coast of Australia, yet maximum intraspecific variation over this gene region was calculated at 0.8%, with minimum interspecific variation at 3%, indicating distinct ranges of variation to be expected at intra- and interspecific levels. This region therefore appears to provide southern African forensic entomologists with a new technique for providing accurate identification for application to estimation of PMI. [source] Reforming hospital nursing: the experiences of Maria MachinNURSING INQUIRY, Issue 4 2006Carol Helmstadter The reform of hospital nursing in the last quarter of the nineteenth century brought nursing leaders into conflict with the gendered and class bound structure of Victorian society. The experiences of Maria Machin are used in this article as an example of the barriers nursing leaders had to overcome in order to establish a competent nursing service. While Machin was eminently successful in improving patient care and expanding the knowledge base of her nurses, she could not change the perceptions of nursing which the public at large held. At the beginning of the nineteenth century hospital nurses had been essentially cleaning women who gave some of the less important nursing care. They formed a cheap service which many hospital governors considered a relatively low priority in the overall operation of the hospital. This view of nursing persisted long after the reformers had made nursing into something quite different. Machin's nursing career also illustrates how nursing participated in a major aspect of British imperialism, the export of professional expertise and administrative skills as well as the way nursing fitted into the rise of the new professionalism. [source] The Paradox of Integration: Habermas and the Unfinished Project of European UnionPOLITICS, Issue 2 2001Shivdeep Singh Grewal In a recent article Jürgen Habermas (1999) highlighted the potential for the European Union to act as a vehicle for the extension of democratic governance beyond the nation state, a project aimed at limiting the socially corrosive impact of globalisation. Yet this position appears paradoxical as the European Union itself exacerbates a major aspect of globalisation: the emasculation of national parliaments known as the ,democratic deficit'. This paradox can be understood by analysing the dynamics of post-war European integration through the lens of Habermasian social theory: EU evolution can lead either to the colonisation of the lifeworld by market and administrative subsystems (as with the democratic deficit), or to a process of lifeworld rationalisation conducive to pan-European solidarity and democracy. The latter of these tendencies could be encouraged through ,procedural democracy': this would institutionalise the conditions by which independent associations in European civil society, channelling their ,communicative power' through parliament, might reassert control over the two subsystems. In order to retain legitimacy, procedural EU democracy would have to link existing legislatures to the European Parliament, while citizenship would combine national and civic components. Hence the European Union would be more able than the nation-state to combine universal notions of justice with ethical pluralism. [source] Some reflections concerning GDP, regional convergence and European cohesion policyREGIONAL SCIENCE POLICY AND PRACTICE, Issue 1 2008N. De Michelis regional policy; cohesion policy; regional convergence; European Union Abstract The main objectives of the European cohesion policy have often been translated as the promotion of convergence between EU regions, which is most frequently measured as the decrease in disparities between the levels of regional GDP per head. This type of convergence has even become a major aspect in assessing the effectiveness of European cohesion policy. This paper first discusses the capacity of conventional convergence measures to capture the evolution of regional disparities in Europe. It then reflects on the information conveyed by this type of analysis concerning the effectiveness of cohesion policy. [source] Lead in soil by field-portable x-ray fluorescence spectrometry,an examination of paired In Situ and laboratory ICP-AES resultsREMEDIATION, Issue 3 2008David A. Binstock A major aspect of lead hazard control is the evaluation of soil lead hazards around housing coated with lead-based paint. The use of field-portable X-ray fluorescence (FPXRF) to do detailed surveying, with limited laboratory confirmation, can provide lead measurements in soil (especially for planning abatement activities) in a far more cost-efficient and timely manner than laboratory analysis. To date, one obstacle to the acceptance of FPXRF as an approved method of measuring lead in soil has been a lack of correspondence between field and laboratory results. In order to minimize the differences between field and laboratory results, RTI International (RTI) has developed a new protocol for field drying and sieving soil samples for field measurement by FPXRF. To evaluate this new protocol, composite samples were collected in the field following both U.S. Department of Housing and Urban Development (HUD) guidelines and ASTM International (ASTM) protocols, measured after drying by FPXRF, and returned to the laboratory for confirmatory inductively coupled plasma atomic emission spectroscopy (ICP-AES) analysis. Evaluation of study data from several diverse sites revealed no statistical difference between paired FPXRF and ICP-AES measurements using the new method. © 2008 Wiley Periodicals, Inc. [source] Fast, scalable, and distributed restoration in general mesh optical networksBELL LABS TECHNICAL JOURNAL, Issue 1 2001Gary P. Austin Service providers are demanding transport network solutions that can accommodate exponential traffic growth and, at the same time, provide novel services such as point-and-click provisioning of very high bandwidth circuits, optical bandwidth service management, fast protection and restoration, and bandwidth on demand. It is becoming increasingly clear that the required scalability (terabits/s to petabits/s) and cost structure can only be provided by transparent optical cross connects (OXCs). The challenge, then, is to make the optical network consisting of OXCs, dense wavelength division multiplexers (DWDMs), and optical add/drop multiplexers (OADMs) dynamic and intelligent. A major aspect of this intelligence is fast provisioning and restoration. In this paper, we present a fast, scalable, and distributed solution for optical layer restoration in general mesh-type optical networks, which is being implemented as part of the Optical Navigator System (ONS) residing in Lucent's LambdaRouter product. The key ingredients to our solution are a fast and scalable restoration strategy, a fast and scalable connection setup strategy, a contention-free wavelength assignment strategy, and a fast and reliable data communications network to exchange signaling messages. We also introduce novel concepts of demand bundling and optical virtual paths that ensure that restoration performance scales with network and traffic volumes. Together these components provide an intelligent optical networking solution that not only guarantees restoration times within few hundreds of milliseconds, but also achieves scalability. [source] Stuck in the past: negative bias, explanatory style, temporal order, and evaluative perspectives in life narratives of clinically depressed individualsDEPRESSION AND ANXIETY, Issue 11 2008Tilmann Habermas Ph.D. Abstract This study attempted to replicate negative bias and depressive explanatory style in depression using life narratives. The two central aspects of narrative, temporal succession and evaluation, were also explored. These aspects were tested for the first time using entire life narratives of 17 depressed inpatients and non-depressed controls matched for sex and educational level. Negative bias and depressive explanatory style were replicated as typical for the depressed group. Life narratives of depressed patients also deviated more from a linear temporal order and compared less frequently the past with the present. Contrary to expectations, the depressed did not differ in the overall frequency of evaluations. However, they used more past than present evaluations and more experience-near evaluations than cognitive evaluations, suggesting that they are more immersed in past experiences. It is concluded that negative bias and depressive explanatory style can be found also in a naturalistic narrative measure, and that depression affects the two major aspects of narrative. It is argued that life narratives, as measures close to everyday clinical practice and as the most encompassing form of self-representation, should complement more experimental procedures in the study of cognitive and communicative processes in psychopathology. Depression and Anxiety, 2008. © 2007 Wiley-Liss, Inc. [source] What drives cell morphogenesis: A look inside the vertebrate photoreceptorDEVELOPMENTAL DYNAMICS, Issue 9 2009Breandán Kennedy Abstract Vision mediating photoreceptor cells are specialized light-sensitive neurons in the outer layer of the vertebrate retina. The human retina contains approximately 130 million of such photoreceptors, which enable images of the external environment to be captured at high resolution and high sensitivity. Rod and cone photoreceptor subtypes are further specialized for sensing light in low and high illumination, respectively. To enable visual function, these photoreceptors have developed elaborate morphological domains for the detection of light (outer segments), for changing cell shape (inner segments), and for communication with neighboring retinal neurons (synaptic terminals). Furthermore, rod and cone subtypes feature unique morphological variations of these specialized characteristics. Here, we review the major aspects of vertebrate photoreceptor morphology and key genetic mechanisms that drive their formation. These mechanisms are necessary for cell differentiation as well as function. Their defects lead to cell death. Developmental Dynamics 238:2115,2138, 2009. © 2009 Wiley-Liss, Inc. [source] PERSPECTIVE: Linking concepts in the ecology and evolution of invasive plants: network analysis shows what has been most studied and identifies knowledge gapsEVOLUTIONARY APPLICATIONS (ELECTRONIC), Issue 2 2010Sonia Vanderhoeven Abstract In recent decades, a growing number of studies have addressed connections between ecological and evolutionary concepts in biologic invasions. These connections may be crucial for understanding the processes underlying invaders' success. However, the extent to which scientists have worked on the integration of the ecology and evolution of invasive plants is poorly documented, as few attempts have been made to evaluate these efforts in invasion biology research. Such analysis can facilitate recognize well-documented relationships and identify gaps in our knowledge. In this study, we used a network-based method for visualizing the connections between major aspects of ecology and evolution in the primary research literature. Using the family Poaceae as an example, we show that ecological concepts were more studied and better interconnected than were evolutionary concepts. Several possible connections were not documented at all, representing knowledge gaps between ecology and evolution of invaders. Among knowledge gaps, the concepts of plasticity, gene flow, epigenetics and human influence were particularly under-connected. We discuss five possible research avenues to better understand the relationships between ecology and evolution in the success of Poaceae, and of alien plants in general. [source] Exploring the mast cell enigma: a personal reflection of what remains to be doneEXPERIMENTAL DERMATOLOGY, Issue 2 2008Beate M. Henz Abstract: Mast cells are traditionally viewed as effector cells of allergic reactions and parasitic diseases, but their importance in host defense against bacteria, in tissue remodelling, their bone marrow and stem cell origin and a central role of the stem cell factor (SCF) as mast cell growth and chemotactic factor has been worked out only in recent years. Despite this, major aspects about the nature of the cells and their role in disease remain unclear. This holds in particular for the identification of mast cell precursors and the role of growth factors that stimulate specific mast cell commitment from stem cells, such as nerve growth factor, neutrotrophin-3 and certain interleukins, alone and during interaction with SCF. Early data suggesting also an involvement of specific transcription factors need to be expanded in this process. Furthermore, although mast cell proliferative disease (mastocytosis) has been shown to be often associated with SCF receptor c-kit mutations, reasons for the development of this disease remain unclear. This holds also for mast cell release mechanisms in many types of mast cell-dependent urticaria. Exciting new insights are emerging regarding the role of mast cells in bacterial infections, in defense against tumors, in wound healing and in the interplay with the nervous system, with hormones, and in the neurohormonal network. The aim of this reflection is to delineate the many known and unknown aspects of mast cells, with a special focus on their development, and to discuss in detail two mast cell-related diseases, namely mastocytosis and urticaria. [source] Characterization of ,-synuclein aggregation and synergistic toxicity with protein tau in yeastFEBS JOURNAL, Issue 6 2005Piotr Zabrocki A yeast model was generated to study the mechanisms and phenotypical repercussions of expression of ,-synuclein as well as the coexpression of protein tau. The data show that aggregation of ,-synuclein is a nucleation,elongation process initiated at the plasma membrane. Aggregation is consistently enhanced by dimethyl sulfoxide, which is known to increase the level of phospholipids and membranes in yeast cells. Aggregation of ,-synuclein was also triggered by treatment of the yeast cells with ferrous ions, which are known to increase oxidative stress. In addition, data are presented in support of the hypothesis that degradation of ,-synuclein occurs via autophagy and proteasomes and that aggregation of ,-synuclein disturbs endocytosis. Reminiscent of observations in double-transgenic mice, coexpression of ,-synuclein and protein tau in yeast cells is synergistically toxic, as exemplified by inhibition of proliferation. Taken together, the data show that these yeast models recapitulate major aspects of ,-synuclein aggregation and cytotoxicity, and offer great potential for defining the underlying mechanisms of toxicity and synergistic actions of ,-synuclein and protein tau. [source] A multi-QMOM framework to describe multi-component agglomerates in liquid steelAICHE JOURNAL, Issue 9 2010L. Claudotte Abstract A variant of the quadrature method of moments (QMOM) for solving multiple population balance equations (PBE) is developed with the objective of application to steel industry processing. During the process of oxygen removal in a steel ladle, a large panel of oxide inclusions may be observed depending on the type of oxygen removal and addition elements. The final quality of the steel can be improved by accurate numerical simulation of the multi-component precipitation. The model proposed in this article takes into account the interactions between three major aspects of steelmaking modeling, namely fluid dynamics, thermo-kinetics and population balance. A commercial CFD code is used to predict the liquid steel hydrodynamics, whereas a home-made thermo-kinetic code adjusts chemical composition with nucleation and diffusion growth, and finally a set of PBE tracks the evolution of inclusion size with emphasis on particle aggregation. Each PBE is solved by QMOM, the first PBE/QMOM system describing the clusters and each remaining PBE/QMOM system being dedicated to the elementary particles of each inclusion species. It is shown how this coupled model can be used to investigate the cluster size and composition of a particular grade of steel (i.e., Fe-Al-Ti-O). © 2010 American Institute of Chemical Engineers AIChE J, 2010 [source] Developing Critical Rationality as a Pedagogical AimJOURNAL OF PHILOSOPHY OF EDUCATION, Issue 3 2004Christopher Winch The development of a conception of critical pedagogy is itself an aspect of the development of critical rationality within late modern societies, closely connected with the role of education in developing critical rationality. The role of critique pervades all aspects of life: for people as citizens, workers and self-determining private individuals. Late modern societies depend on a critically minded population for their viability, for the democratic management of a competing balance of interests and for a capacity for rapid renewal. These requirements put a demand on the education system for the development of critical rationality. However, its development contains within itself the seeds, not just of renewal, but of transformation or even anarchy. This is discussed in relation to three major aspects of education,liberal, civic and vocational,and it is argued that there is a tension within each that arises from the requirement of critique for their successful functioning as educational practices in liberal societies and from the implausibility of developing forms of critique that are inherently self-limiting. Societies that espouse the development of critical rationality as a key educational aim exist in a state of tension and of uncertainty as to the extent to which it can be developed. Attempts to limit critique to consideration only of what is worthwhile are bound to be futile. On the other hand, education must be concerned with preparation for the worthwhile. Critique thus performs the important function of ensuring that our conception of the worthwhile does not remain fixed, but is itself an agent of social change. This paper explores this issue and argues that the problem of reconciling preparation for social participation with preparation for critical engagement exists in all three spheres. The problems may not be resolvable ones but should encourage continual awareness of the scope and limits of educational critique in liberal societies. [source] A Primer on Adoption LawJUVENILE AND FAMILY COURT JOURNAL, Issue 3 2001DOUGLAS E. ABRAMS J.D. ABSTRACT This article surveys major aspects of adoption law encountered by judges, lawyers, and child care professionals. The authors, whose new Children and the Law casebook is already required reading in nearly three dozen law schools, analyze both historical and contemporary materials, and both statutory and case law. [source] Quantification of effects of season and nitrogen supply on tree below-ground carbon transfer to ectomycorrhizal fungi and other soil organisms in a boreal pine forestNEW PHYTOLOGIST, Issue 2 2010Mona N. Högberg Summary ,The flux of carbon from tree photosynthesis through roots to ectomycorrhizal (ECM) fungi and other soil organisms is assumed to vary with season and with edaphic factors such as nitrogen availability, but these effects have not been quantified directly in the field. ,To address this deficiency, we conducted high temporal-resolution tracing of 13C from canopy photosynthesis to different groups of soil organisms in a young boreal Pinus sylvestris forest. ,There was a 500% higher below-ground allocation of plant C in the late (August) season compared with the early season (June). Labelled C was primarily found in fungal fatty acid biomarkers (and rarely in bacterial biomarkers), and in Collembola, but not in Acari and Enchytraeidae. The production of sporocarps of ECM fungi was totally dependent on allocation of recent photosynthate in the late season. There was no short-term (2 wk) effect of additions of N to the soil, but after 1 yr, there was a 60% reduction of below-ground C allocation to soil biota. ,Thus, organisms in forest soils, and their roles in ecosystem functions, appear highly sensitive to plant physiological responses to two major aspects of global change: changes in seasonal weather patterns and N eutrophication. [source] Protein,protein docking with multiple residue conformations and residue substitutionsPROTEIN SCIENCE, Issue 6 2002David M. Lorber Abstract The protein docking problem has two major aspects: sampling conformations and orientations, and scoring them for fit. To investigate the extent to which the protein docking problem may be attributed to the sampling of ligand side-chain conformations, multiple conformations of multiple residues were calculated for the uncomplexed (unbound) structures of protein ligands. These ligand conformations were docked into both the complexed (bound) and unbound conformations of the cognate receptors, and their energies were evaluated using an atomistic potential function. The following questions were considered: (1) does the ensemble of precalculated ligand conformations contain a structure similar to the bound form of the ligand? (2) Can the large number of conformations that are calculated be efficiently docked into the receptors? (3) Can near-native complexes be distinguished from non-native complexes? Results from seven test systems suggest that the precalculated ensembles do include side-chain conformations similar to those adopted in the experimental complexes. By assuming additivity among the side chains, the ensemble can be docked in less than 12 h on a desktop computer. These multiconformer dockings produce near-native complexes and also non-native complexes. When docked against the bound conformations of the receptors, the near-native complexes of the unbound ligand were always distinguishable from the non-native complexes. When docked against the unbound conformations of the receptors, the near-native dockings could usually, but not always, be distinguished from the non-native complexes. In every case, docking the unbound ligands with flexible side chains led to better energies and a better distinction between near-native and non-native fits. An extension of this algorithm allowed for docking multiple residue substitutions (mutants) in addition to multiple conformations. The rankings of the docked mutant proteins correlated with experimental binding affinities. These results suggest that sampling multiple residue conformations and residue substitutions of the unbound ligand contributes to, but does not fully provide, a solution to the protein docking problem. Conformational sampling allows a classical atomistic scoring function to be used; such a function may contribute to better selectivity between near-native and non-native complexes. Allowing for receptor flexibility may further extend these results. [source] Principles of evaluating quality investmentsQUALITY AND RELIABILITY ENGINEERING INTERNATIONAL, Issue 5 2008Johannes Freiesleben Abstract Quality departments often experience difficulties selling the idea that first priority should be given to quality improvement. Most approaches to project budgeting favour traditional investments such as new product development, which are perceived as potential profit boosters. To compete with such investments, a clear economic logic is needed, which stresses the long-term benefits of better quality. The aim of this paper, therefore, is to provide a concise framework of how to think about quality investments in economic terms. By focusing on the principles of an economic evaluation, it highlights the major aspects of an improvement assessment and derives a simple measure for helping practitioners to determine the advantageousness of a quality initiative. Copyright © 2008 John Wiley & Sons, Ltd. [source] Control of Cell Volume in Skeletal MuscleBIOLOGICAL REVIEWS, Issue 1 2009Juliet A. Usher-Smith Abstract Regulation of cell volume is a fundamental property of all animal cells and is of particular importance in skeletal muscle where exercise is associated with a wide range of cellular changes that would be expected to influence cell volume. These complex electrical, metabolic and osmotic changes, however, make rigorous study of the consequences of individual factors on muscle volume difficult despite their likely importance during exercise. Recent charge-difference modelling of cell volume distinguishes three major aspects to processes underlying cell volume control: (i) determination by intracellular impermeant solute; (ii) maintenance by metabolically dependent processes directly balancing passive solute and water fluxes that would otherwise cause cell swelling under the influence of intracellular membrane-impermeant solutes; and (iii) volume regulation often involving reversible short-term transmembrane solute transport processes correcting cell volumes towards their normal baselines in response to imposed discrete perturbations. This review covers, in turn, the main predictions from such quantitative analysis and the experimental consequences of comparable alterations in extracellular pH, lactate concentration, membrane potential and extracellular tonicity. The effects of such alterations in the extracellular environment in resting amphibian muscles are then used to reproduce the intracellular changes that occur in each case in exercising muscle. The relative contributions of these various factors to the control of cell volume in resting and exercising skeletal muscle are thus described. [source] | ||||||||||||||||||||||