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Particular Emphasis (particular + emphasis)
Selected AbstractsAnatomy of Primary Afferents and Projection Neurones in the Rat Spinal Dorsal Horn with Particular Emphasis on Substance P and the Neurokinin 1 ReceptorEXPERIMENTAL PHYSIOLOGY, Issue 2 2002A. J. Todd The dorsal horn of the spinal cord plays an important role in transmitting information from nociceptive primary afferent neurones to the brain; however, our knowledge of its neuronal and synaptic organisation is still limited. Nociceptive afferents terminate mainly in laminae I and II and some of these contain substance P. Many projection neurones are located in lamina I and these send axons to various parts of the brain, including the caudal ventrolateral medulla (CVLM), parabrachial area, periaqueductal grey matter and thalamus. The neurokinin 1 (NK1) receptor on which substance P acts is expressed by certain neurones in the dorsal horn, including approximately 80% of lamina I projection neurones. There is also a population of large NK1 receptor-immunoreactive neurones with cell bodies in laminae III and IV which project to the CVLM and parabrachial area. It has been shown that the lamina III/IV NK1 receptor-immunoreactive projection neurones are densely and selectively innervated by substance P-containing primary afferent neurones, and there is evidence that these afferents also target lamina I projection neurones with the receptor. Both types of neurone are innervated by descending serotoninergic axons from the medullary raphe nuclei. The lamina III/IV neurones also receive numerous synapses from axons of local inhibitory interneurones which contain GABA and neuropeptide Y, and again this input shows some specificity since post-synaptic dorsal column neurones which also have cell bodies in laminae III and IV receive few contacts from neuropeptide Y-containing axons. These observations indicate that there are specific patterns of synaptic connectivity within the spinal dorsal horn. [source] Continuing Progressive Deterioration of the Environment in the Aral Sea Region: Disastrous Effects on Mother and Child HealthACTA PAEDIATRICA, Issue 5 2001O Ataniyazova Scientists, non-governmental experts (NGOs) and governmental officials from the Central Asian Republics and an international group of invited scientists and NGO representatives participated in a workshop on the disastrous health problems in the Aral Sea Region. Various serious problems were reported in more than 20 presentations. Particular emphasis was put on the way in which adverse environmental factors such as contaminated water and food have contributed to the deterioration of human health, particularly that of mothers and children. Conclusion: There is an urgent request that the international community assists local scientists to develop programmes to improve the health of the population in the Aral Sea Region. [source] Particle-in-Cell Simulation of Stationary Plasma ThrusterCONTRIBUTIONS TO PLASMA PHYSICS, Issue 8-9 2007F. Taccogna Abstract A very good example for the application of PIC techniques for detailed studies of low-temperature plasmas is the Hall thrusters. Here, a variety of models with different complexities are needed to get better insight into the physics of these systems. Particular emphasis has been spent for the geometrical scaling, for the simulation of the plasma-wall interaction inside the acceleration channel and for ion-neutral collision into the plume emitted from the thruster. Results show the axial acceleration mechanism, the secondary electron emission instability, the azimuthal fluctuations into the channel and the ion backflow and electron trapping in the plume. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Unequal Knowledges in Jharkhand, India: De-Romanticizing Women's Agroecological ExpertiseDEVELOPMENT AND CHANGE, Issue 5 2000Sarah Jewitt Taking the Jharkhand region of India as a case study, this article uses empirical data to intervene in ,women, environment and development' and ecofeminist debates regarding women's environmental knowledge. The article first outlines the adoption of gender/environmental issues into development planning and considers the dangers of overestimating women's agroecological knowledges and assuming that they can easily participate in development projects. It then highlights the local complexities of environmental knowledge possession and control with reference to gender and other variations in agricultural participation, decision-making and knowledge transfers between villagers' natal and marital places. Particular emphasis is placed on the economic, socio-cultural and ,actor' related factors that supplement gender as an influence on task allocation, decision-making, knowledge distribution and knowledge articulation. The article concludes that given the socio-cultural constraints women face in accumulating and vocalizing environmental knowledge, simplistic participatory approaches are unlikely to empower them. Instead, more flexible, site-specific development initiatives (coupled with wider structural change) are required if opportunities are to be created for women to develop and use their agroecological knowledges. [source] BioPrEP , a regional, process-based approach for assessment of land with high conservation value for Bush Heritage AustraliaECOLOGICAL MANAGEMENT & RESTORATION, Issue 1 2010Brendan Mackey Summary, A framework is presented for terrestrial conservation assessment that has been developed for Bush Heritage, an Australian non-profit organisation that manages land of outstanding conservation value through acquisition or working in partnership with other landowners. The framework is called Biodiversity Prediction using Ecological Processes and comprises seven conservation goals, with a set of candidate criteria and indicators for each goal. Particular emphasis is given to criteria that relate to habitat quality in addition to the more conventional focus on land quantity. The MCAS-S graphic user interface is used to help analyse the indicators and visualise the results in a transparent way that assists the decision-making process. The interface also allows indicators to be weighted differently, which among other things, allows analyses to reflect inter-regional differences in what represents high quality land. The framework was tested in a case study region (the Woodland region of south-eastern Australia), and the results reveal land that is potentially a priority for conservation investments. While the framework and case study results are indicative, and further analyses are required before they can be considered operational, the approach has potential application to other organisations in the private conservation sector. [source] Predicting species distribution: offering more than simple habitat modelsECOLOGY LETTERS, Issue 9 2005Antoine Guisan Abstract In the last two decades, interest in species distribution models (SDMs) of plants and animals has grown dramatically. Recent advances in SDMs allow us to potentially forecast anthropogenic effects on patterns of biodiversity at different spatial scales. However, some limitations still preclude the use of SDMs in many theoretical and practical applications. Here, we provide an overview of recent advances in this field, discuss the ecological principles and assumptions underpinning SDMs, and highlight critical limitations and decisions inherent in the construction and evaluation of SDMs. Particular emphasis is given to the use of SDMs for the assessment of climate change impacts and conservation management issues. We suggest new avenues for incorporating species migration, population dynamics, biotic interactions and community ecology into SDMs at multiple spatial scales. Addressing all these issues requires a better integration of SDMs with ecological theory. [source] MARGINAL VS INFRAMARGINAL ANALYSIS AND THE THEORY OF DISTRIBUTION VS THE DEVELOPMENT OF A THEORY OF ECONOMIC ORGANISATIONECONOMIC PAPERS: A JOURNAL OF APPLIED ECONOMICS AND POLICY, Issue 2 2006CHRISTIS G. TOMBAZOS This paper serves as a short introduction to inframarginal economics. Particular emphasis is given to the historical relevance of this approach, as well as to its key feature of reconciling neoclassical questions of distribution with classical insights regarding economic organisation. [source] Paroxysmal Motor Disorders of Sleep: The Clinical Spectrum and Differentiation from EpilepsyEPILEPSIA, Issue 11 2006Christopher P. Derry Summary:, The diagnosis of paroxysmal events in sleep represents a significant challenge for the clinician, with the distinction of nocturnal epilepsy from nonepileptic sleep disorders often the primary concern. Diagnostic error or uncertainty is not uncommon in this situation, particularly with respect to nocturnal frontal lobe epilepsy (NFLE), which has a variable and often unusual presentation. Such errors can be minimized if the range of nonepileptic disorders with motor activity in sleep is fully appreciated. Here we review these disorders, before discussing the important clinical and electrographic features that allow their accurate differentiation from seizures. Particular emphasis is placed on the differentiation of nocturnal frontal lobe epilepsy from non,rapid eye movement (NREM) arousal disorders and other parasomnias. The value of recording episodes with video EEG polysomnography is discussed. [source] String theory: exact solutions, marginal deformations and hyperbolic spacesFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 2 2007D. Orlando Abstract This thesis is almost entirely devoted to studying string theory backgrounds characterized by simple geometrical and integrability properties. The archetype of this type of system is given by Wess-Zumino-Witten models, describing string propagation in a group manifold or, equivalently, a class of conformal field theories with current algebras. We study the moduli space of such models by using truly marginal deformations. Particular emphasis is placed on asymmetric deformations that, together with the CFT description, enjoy a very nice spacetime interpretation in terms of the underlying Lie algebra. Then we take a slight detour so to deal with off-shell systems. Using a renormalization-group approach we describe the relaxation towards the symmetrical equilibrium situation. In he final chapter we consider backgrounds with Ramond-Ramond field and in particular we analyze direct products of constant-curvature spaces and find solutions with hyperbolic spaces. [source] Cavity QED with a trapped ionFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 2-3 2003W. Vogel A trapped ion in a leaky cavity is studied in the regime of strong atom-field coupling. Particular emphasis is paid on nonlinearities due to smooth localization of the ion's wavefunction and on decoherence effects caused by spontaneous emission and cavity losses. Possibilities of quantum-state preparation are analyzed and single-ion lasing is considered. [source] The Difficulty of Justifying European Integration as a Consequence of Depoliticization: Evidence from the 2005 French ReferendumGOVERNMENT AND OPPOSITION, Issue 3 2009Andrew Glencross This article analyses the 2005 French referendum debate on the EU Constitutional Treaty as an instance of depoliticization. Particular emphasis is placed on the argumentative strategy of President Chirac as, despite the treaty's focus on institutional reform, he eventually chose to justify the document in terms of social policy: an ultimately unconvincing strategy because voters believed it was contradicted by current EU policy priorities. On this evidence, pace Glyn Morgan, prioritizing a justification of EU finality over that of institutions and policies does not seem appropriate. Rather, the priority for integration is to overcome elites' strategies of depoliticization during referendum campaigns. [source] Theory and numerics of geometrically non-linear open system mechanicsINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 11 2003E. Kuhl Abstract The present contribution aims at deriving a general theoretical and numerical framework for open system thermodynamics. The balance equations for open systems differ from the classical balance equations by additional terms arising from possible local changes in mass. In contrast to existing formulations, these changes not only originate from additional mass sources or sinks but also from a possible in- or outflux of matter. Constitutive equations for the mass source and the mass flux are discussed for the particular model problem of bone remodelling in hard tissue mechanics. Particular emphasis is dedicated to the spatial discretization of the coupled system of the balance of mass and momentum. To this end we suggest a geometrically non-linear monolithic finite element based solution technique introducing the density and the deformation map as primary unknowns. It is supplemented by the consistent linearization of the governing equations. The resulting algorithm is validated qualitatively for classical examples from structural mechanics as well as for biomechanical applications with particular focus on the functional adaption of bones. It turns out that, owing to the additional incorporation of the mass flux, the proposed model is able to simulate size effects typically encountered in microstructural materials such as open-pored cellular solids, e.g. bones. Copyright © 2003 John Wiley & Sons, Ltd. [source] The importance of volunteers in a capital campaignINTERNATIONAL JOURNAL OF NONPROFIT & VOLUNTARY SECTOR MARKETING, Issue 4 2002Article first published online: 12 JUL 200, Linda Lysakowski One of the most significant factors in the success of any capital campaign is the number, quality and commitment of volunteers used to guide, implement and promote the campaign. This paper will discuss the importance of using volunteers and the critical roles they play within the campaign. The volunteer as giver, asker and motivator will be explained. An example of a typical campaign organisational chart is provided to help the reader identify the number and types of volunteers necessary to implement a successful campaign. Volunteers have many roles to play, and getting the right person to fill each of these roles is essential to success. Methods for recruiting volunteers and the materials that are needed to implement a successful recruitment strategy are included in this discussion. Particular emphasis is placed on the role of the campaign chair as the leader of the campaign effort. The unique role of the Board of Directors as volunteers during a capital campaign is addressed in this paper. Strategies for keeping volunteers involved and motivated are discussed, along with tips to make the volunteer campaign experience a satisfying one for both staff and volunteer. In summary, the author contends that the use of volunteers in a capital campaign is essential to the success of the campaign. Copyright © 2002 Henry Stewart Publications [source] Contingent Chicago: Restructuring the Spaces of Temporary LaborINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 3 2001Jamie Peck Hiring-halls, specializing in the placement of day-laborers in temporary jobs, have in recent years been proliferating along major transport arteries in Chicago's low-income neighborhoods. This article examines the phenomenon of low-wage temporary work in Chicago from the perspective of the principal institutional actors in these highly ,flexibilized' or ,contingent' labor markets , the ,temp' agencies. Particular emphasis is placed on the labor-market effects of temp-agency strategies, both in respect to patterns of labor segmentation and in terms of the spatial (re)constitution of urban job markets. It is suggested that temp agencies are actively engaged in both the exploitation and facilitation of contingent labor-market conditions. In this sense, they are assuming important new roles as privatized ,labor-market intermediaries', with apparently deleterious effects for job security and social segregation in the lower reaches of urban labor markets. Their strategies can also be related to the social and geographic restructuring of these job markets, because the growth and polarization of temp employment has been associated with a ,hardening', and indeed ,stretching', of extant ethnic, gender and spatial inequalities. Des bureaux d'embauche, spécialisés dans le placement de journaliers sur des postes temporaires, ont récemment proliféré le long des grands axes de transport dans les quartiers défavorisés de Chicago. Cet article étudie le phénomène du travail temporaire à faible revenu dans cette ville, et ce, du point de vue des principaux acteurs institutionnels sur ces marchés du travail hautement ,flexibilisés' ou ,aléatoires': les agences de travail temporaire. Il insiste sur les conséquences des stratégies de ces agences pour le marché de l'emploi, à la fois au niveau des schémas de segmentation du travail et en termes de (re)constitution spatiale des marchés du travail urbains. Aussi peut-on suggérer que ces agences sont activement impliquées dans l'exploitation et la facilitation des conditions aléatoires du marché du travail. En ce sens, elles jouent un rôle important et nouveau comme ,intermédiaires du marché du travail' privatisés, avec des effets apparemment néfastes pour la sécurité de l'emploi et la ségrégation sociale dans les circuits inférieurs des marchés urbains. Leurs stratégies peuvent aussi être liées à la restructuration sociale et géographique de ces marchés, la croissance et la polarisation de l'emploi temporaire ayant ètè associées à un ,durcissement', et assurément à une ,extension', des inégalités existantes au plan ethnique, spatial et des sexes. [source] A single-crystal time-of-flight neutron diffractometer at a spallation neutron sourceJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 4 2007Miwako Takahashi A single-crystal diffractometer using the time-of-flight (TOF) Laue technique had been operated for studies of structural and magnetic disorder and phase transitions in alloys and magnetic materials at the pulsed spallation neutron source facility of the KEK Neutron Science Laboratory (KENS). In various sample environments, the diffractometer has demonstrated its usefulness in measurements of diffuse scattering for studying local structures, and in surveys of reciprocal space for studying phase transitions and incommensurate structures under the conditions of varying temperature and magnetic field. Particular emphasis is placed on the fact that though the instrument did not receive high-flux neutrons for long wavelengths suitable for the studies of magnetic scattering, it gave good results on the observations of magnetic diffuse scattering and superlattice reflections. Remarks and future tasks of the TOF Laue technique are discussed in relation to the asymmetric pulse shape, separation of the inelastic scattering, and dependence of data correction on the sample quality. [source] Respiratory hypersensitivity to trimellitic anhydride in Brown Norway Rats: a comparison of endpointsJOURNAL OF APPLIED TOXICOLOGY, Issue 2 2002Jürgen Pauluhn Abstract A rat bioassay has been developed to provide an objective approach for the identification and classification of respiratory allergy using trimellitic anhydride (TMA), which is a known respiratory tract irritant and asthmagen. Particular emphasis was placed on the study of route-of-induction-dependent effects and their progression upon inhalation challenge with TMA (,23 mg m,3 for a duration of 30 min), which included analysis of specific and non-specific airway hyperreactivity and pulmonary inflammation initiated and sustained by immunological processes. Refinement of the bioassay focused on procedures to probe changes occurring upon challenge with TMA or methacholine aerosols using physiological, biochemical and immunological procedures. Following challenge with TMA, the rats sensitized to TMA showed marked changes in peak inspiratory and expiratory air flows and respiratory minute volume. In these animals, a sustained pulmonary inflammation occurred, characterized by specific endpoints determined in bronchoalveolar lavage (lactate dehydrogenase, protein, nitrite, eosinophil peroxidase, myeloperoxidase). When compared with the naive controls, lung weights were increased significantly, as were the weights of lung-associated lymph nodes following inhalation induction and auricular lymph nodes following topical induction. The extent of changes observed was equal or more pronounced in animals sensitized epicutaneously (day 0 : 150 µl vehicle/50% TMA on each flank, day 7; booster administration to the skin of the dorsum of both ears using half the concentration and volume used on day 0) when compared with rats sensitized by 5 × 3 h day,1 inhalation exposures (low dose: 25 mg TMA m,3, high dose: 120 mg TMA m,3). In summary, the findings support the conclusion that the Brown Norway rat model is suitable for identifying TMA as an agent that causes both an immediate-type change of breathing patterns and a delayed-type sustained pulmonary inflammatory response. However, it remains unresolved whether the marked effects observed in the topically sensitized rats are more related to a route-of-induction or dose-dependent phenomenon. Copyright © 2002 John Wiley & Sons, Ltd. [source] Programme Evaluation with Multiple TreatmentsJOURNAL OF ECONOMIC SURVEYS, Issue 2 2004Markus Frölich Abstract., This paper reviews the main identification and estimation strategies for microeconometric policy evaluation. Particular emphasis is laid on evaluating policies consisting of multiple programmes, which is of high relevance in practice. For example, active labour market policies may consist of different training programmes, employment programmes and wage subsidies. Similarly, sickness rehabilitation policies often offer different vocational as well as non-vocational rehabilitation measures. First, the main identification strategies (control-for-confounding-variables, difference-in-difference, instrumental-variable, and regression-discontinuity identification) are discussed in the multiple-programme setting. Thereafter, the different nonparametric matching and weighting estimators of the average treatment effects and their properties are examined. [source] Cost- and Income-based Measures of Human CapitalJOURNAL OF ECONOMIC SURVEYS, Issue 3 2003Trinh Le Human capital is increasingly believed to play an important role in the growth process, however, adequately measuring its stock remains controversial. In this paper three general approaches to measurement are identified; cost-based, income-based and educational stock-based. This survey focuses on the first two approaches and provides a critical review of the theories and their applications to data from a range of countries. Particular emphasis is placed upon the work of Jorgenson and Fraumeni (1989, 1992) and some new results for New Zealand based upon their approach are also presented. [source] Challenges to interpretation of breast MRIJOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 6 2001Karen Kinkel MD Abstract This review describes the current knowledge and challenges of lesion interpretation with MRI of the breast according to different image interpretation strategies. Particular emphasis is given to patient- and tumor-related factors that influence image interpretation. The impacts of the menstrual cycle, prior surgery, radiation therapy, and chemotherapy are summarized. Particular enhancement features of ductal carcinoma in situ (DCIS) or invasive lobular carcinoma are described. Finally, an adequate diagnosis at MRI of the breast should take into account the results of the patient's history, physical examination, and all imaging tests performed before MRI. J. Magn. Reson. Imaging 2001;13:821,829. © 2001 Wiley-Liss, Inc. [source] Intra-articular depot formulation principles: Role in the management of postoperative pain and arthritic disordersJOURNAL OF PHARMACEUTICAL SCIENCES, Issue 11 2008Claus Larsen Abstract The joint cavity constitutes a discrete anatomical compartment that allows for local drug action after intra-articular injection. Drug delivery systems providing local prolonged drug action are warranted in the management of postoperative pain and not least arthritic disorders such as osteoarthritis. The present review surveys various themes related to the accomplishment of the correct timing of the events leading to optimal drug action in the joint space over a desired time period. This includes a brief account on (patho)physiological conditions and novel potential drug targets (and their location within the synovial space). Particular emphasis is paid to (i) the potential feasibility of various depot formulation principles for the intra-articular route of administration including their manufacture, drug release characteristics and in vivo fate, and (ii) how release, mass transfer and equilibrium processes may affect the intra-articular residence time and concentration of the active species at the ultimate receptor site. © 2008 Wiley-Liss, Inc. and the American Pharmacists Association J Pharm Sci 97:4622,4654, 2008 [source] Monitoring the corrosion and remediation of reinforced concrete on-site: An alternative approachMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 4 2005N. Birbilis Abstract Difficulties associated with the interpretation of site data collected over long periods of time from commonly used electrochemical corrosion monitoring techniques often make it difficult to assess the corrosion of reinforcing steel. An alternative approach for the interpretation of data is proposed, based on a model of the quality of passive film upon the steel surface. This model leads to a representation of the corrosion state by means of the relationship, over a long period of time, of the corrosion potential and the logarithm of the Linear Polarization Resistance, since both are functions inter alia of corrosion rate. It is shown that for the reinforced concrete panels tested, data points representing this relationship closely fitted a family of results; allowing the development of a "monitoring control diagram", MCD. The MCD reveals that for a fixed geometry and experimental conditions, a relationship between the corrosion potential and polarization resistance of steel exists, facilitating a useful monitoring tool for assessment of both the corrosion and remediation of reinforced concrete structures. Particular emphasis is placed on the latter in this work. [source] Verhalten laserschockverfestigter und festgewalzter Randschichten der Ti-Legierung Ti-6Al-4V bei schwingender Beanspruchung unter erhöhten TemperaturenMATERIALWISSENSCHAFT UND WERKSTOFFTECHNIK, Issue 6 2003I. Altenberger Laser Shock Peening; Deep Rolling; Residual Stresses; Ti-6-4 Abstract Es ist seit langem bekannt, dass mechanische Oberflächenbehandlungen wie etwa Festwalzen, Kugelstrahlen oder Laserschockoberflächenbehandlungen, um nur einige zu nennen, das Ermüdungsverhalten hochbeanspruchter metallischer Bauteile entscheidend verbessern können. Insbesondere Festwalzen und Laserschockoberflächenbehandlungen haben sich als besonders wirksam herausgestellt, da sie tiefe Druckeigenspannungs- und Verfestigungsprofile sowie eine vergleichsweise glatte Oberflächentopographie erzeugen. Tatsächlich wird z.,B. das Festwalzen bereits serienmässig zur Erhöhung der Schwingfestigkeit von Stählen, wie etwa beim Festwalzen von Kurbelwellen, eingesetzt. Obwohl die meisten Arbeiten zum Festwalzen sich mit Stählen beschäftigen, wurde dieses Verfahren in jüngerer Zeit auch auf eine Reihe von Titanwerkstoffen erfolgreich angewendet. Die vorliegenden Untersuchungen beschäftigen sich mit dem Einfluss von Festwalzbehandlungen auf das Niedrig- und Hochlastwechselermüdungsverhalten der wichtigsten kommerziellen Titanlegierung Ti-6Al-4V, wobei besonderes Augenmerk auf die thermische und mechanische Stabilität randnaher Eigenspannungszustände und Mikrostrukturen gerichtet wurde. Zusätzlich werden erste Ergebnisse zum Eigenspannungszustand und zur Schwingfestigkeit lasergeschockter Ti-6Al-4V-Proben präsentiert und mit Resultaten festgewalzter Zustände verglichen. Ausserdem wird untersucht, ob die Oberflächenbehandlungen auch bei erhöhten Temperaturen (bis 450,°C) ihre Wirksamkeit zur Verbesserung der Schwingfestigkeit behalten. Basierend auf Wechselverformungs- und Lebensdaueruntersuchungen, in Kombination mit Röntgendiffraktometrie und In-situ -Transmissionselektronenmikroskopie, lässt sich feststellen, dass Laserschockoberflächenbehandlungen und insbesondere Festwalzen die Rissbildung und Ausbreitung in hochtemperaturschwingbeanspruchtem Ti-6Al-4V trotz eines fast völligen Druckeigenspannungsabbaus wirkungsvoll hemmt. Daraus lässt sich ableiten, dass zusätzlich zu Eigenspannungen vor allem randnahe Mikrostrukturen, welche im Falle von mechanisch randschichtverfestigtem Ti-6Al-4V durch sehr hohe Versetzungsdichten und Nanokristallite gekennzeichnet ist, einen wesentlichen Einfluss bei der Lebensdauererhöhung durch Randschichtverfestigung haben. Residual stress stability and near-surface microstructures in high temperature fatigued mechanically surface treated Ti-6Al-4V It is well known that mechanical surface treatments, such as deep rolling, shot peening and laser shock peening, can significantly improve the fatigue behavior of highly-stressed metallic components. Deep rolling is particularly attractive since it is possible to generate, near the surface, deep compressive residual stresses and work hardened layers while retaining a relatively smooth surface finish. In the present investigation, the effect of deep rolling on the low-cycle and high-cycle fatigue behavior of a Ti-6Al-4V alloy is examined, with particular emphasis on the thermal and mechanical stability of the residual stress states and the near-surface microstructures. Preliminary results on laser shock peened Ti-6Al-4V are also presented for comparison. Particular emphasis is devoted to the question of whether such surface treatments are effective for improving the fatigue properties at elevated temperatures up to ,450,°C, i.e., at an homologous temperature of ,0.4 T/Tm (where Tm is the melting temperature). Based on cyclic deformation and stress/life (S/N) fatigue behavior, together with the X-ray diffraction and in situ transmission electron microscopy observations of the microstructure, it was found that deep rolling can be quite effective in retarding the initiation and initial propagation of fatigue cracks in Ti-6Al-4V at such higher temperatures, despite the almost complete relaxation of the near-surface residual stresses. In the absence of such stresses, it is shown that the near-surface microstructures, which in Ti-6Al-4V consist of a layer of work hardened nanoscale grains, play a critical role in the enhancement of fatigue life by mechanical surface treatment. [source] Liposome/water lipophilicity: Methods, information content, and pharmaceutical applicationsMEDICINAL RESEARCH REVIEWS, Issue 3 2004Georgette Plemper van Balen Abstract This review discusses liposome/water lipophilicity in terms of the structure of liposomes, experimental methods, and information content. In a first part, the structural properties of the hydrophobic core and polar surface of liposomes are examined in the light of potential interactions with solute molecules. Particular emphasis is placed on the physicochemical properties of polar headgroups of lipids in liposomes. A second part is dedicated to three useful methods to study liposome/water partitioning, namely potentiometry, equilibrium dialysis, and 1H-NMR relaxation rates. In each case, the principle and limitations of the method are discussed. The next part presents the structural information encoded in liposome/water lipophilicity, in other words the solutes' structural and physicochemical properties that determine their behavior and hence their partitioning in such systems. This presentation is based on a comparison between isotropic (i.e., solvent/water) and anisotropic (e.g., liposome/water) systems. An important factor to be considered is whether the anisotropic lipid phase is ionized or not. Three examples taken from the authors' laboratories are discussed to illustrate the factors or combinations thereof that govern liposome/water lipophilicity, namely (a) hydrophobic interactions alone, (b) hydrophobic and polar interactions, and (c) conformational effects plus hydrophobic and ionic interactions. The next part presents two studies taken from the field of QSAR to exemplify the use of liposome/water lipophilicity in structure,disposition and structure,activity relationships. In the conclusion, we summarize the interests and limitations of this technology and point to promising developments. © 2004 Wiley Periodicals, Inc. Med Res Rev, 24, No. 3, 299,324, 2004 [source] Regulation of the tetrapyrrole biosynthetic pathway leading to heme and chlorophyll in plants and cyanobacteriaPHYSIOLOGIA PLANTARUM, Issue 1 2002Dmitrii V. Vavilin Photosynthetic organisms synthesize chlorophylls, hemes, and bilin pigments via a common tetrapyrrole biosynthetic pathway. This review summarizes current knowledge about the regulation of this pathway in plants, algae, and cyanobacteria. Particular emphasis is placed on the regulation of glutamate-1-semialdehyde formation and on the channelling of protoporphyrin IX into the heme and chlorophyll branches. The potential role of chlorophyll molecules that are not bound to photosynthetic pigment-protein complexes (,free chlorophylls') or of other Mg-containing porphyrins in regulation of tetrapyrrole synthesis is also discussed. [source] Quality management and quality practice: Perspectives on their history and their futureAPPLIED STOCHASTIC MODELS IN BUSINESS AND INDUSTRY, Issue 1 2009N. I. Fisher Abstract The purpose of this article and a companion article is to explore a number of topics in Statistics in Business and Industry. This article sketches the history of Quality Management, from its emergence in the late 19th and early 20th centuries through to the present day. Particular emphasis is placed on activities in Japan immediately following the end of the Second World War, and subsequent developments elsewhere in the world. We draw a careful distinction between Quality Management and various methodologies that aid in its implementation, such as Six Sigma. In the words of one management practitioner, Norbert Vogel, ,TQM in its broadest sense examines all aspects of management and the alternative methodologies being promoted are merely sub-sets of what should be an integrated management system.' The article concludes with some speculative thoughts about the future of Quality Management from a statistician's point of view. Copyright © 2009 John Wiley & Sons, Ltd. [source] Leukocyte Recruitment and the Acute Inflammatory ResponseBRAIN PATHOLOGY, Issue 1 2000Paul Kubes Leukocyte recruitment is a hallmark feature of the inflammatory response. This review summarizes the generally accepted paradigm of leukocyte recruitment based on studies using intravital microscopy to visualize the microcirculation. The role of selectins and ,4 -integrin in rolling as well as integrin-mediated adhesion is discussed. However, it is becoming increasingly clear that the recruitment cascade within organs differs and therefore the review also attempts to highlight what is and is not known regarding leukocyte recruitment into the brain microvasculature. In the second part of this review, we provide some discussion of mechanisms by which the inflammatory response may be terminated. Particular emphasis on nuclear factor Nf,B and how IL10, IL13 and secreted leukocyte protease inhibitor (SLPI) may impact upon the Nf,B-dependent inflammatory response is presented. [source] Most readily usable methods to measure ocular blood flowACTA OPHTHALMOLOGICA, Issue 2009K GUGLETA Purpose SIS Lecture. Methods Literature search. Results Ocular Blood Flow Research Association (OBFRA, recently merged with another organization - ISOCO, into one single Association for Ocular CDirculation - AOC) made a significant contribution to standardization of the blood flow measuring techniques in the field of ophthalmology. A consens was reached on the number of OBF measurements techniques that occured in the past decades. Particular emphasis was placed on the basic technology, specific parameters and interpretation, accuracy and reproducibility, field of clinical applications. Open questions were extensively discussed, limits of each technique clearly postulated. and a consensus statement put together for each of the technique involved. It encompassed techniques like color Doppler imaging, laser Doppler flowmetry (continuous as well as scanning LDF), laser Doppler velocimetry, Retinal Vessel Analyzer, combination of the vessel diameter measurement and the LDV, laser interferometry of the fundus pulsations amplitude, retinal oxymetry, measurements of the pulsatile component of the blood flow, blue field entoptic method and the newest - Doppler OCT. Conclusion There is no overwhelming measuring technique able to cover all the aspects of the research and the daily clinical routine. Various parameters and various vascular beds are involved, which makes the interpretation of the obtained results strenuous. Of particular importance is the capability of OBF measuring techniques to capture one dynamic feature of ocular circulation - its ability to regulate and to response to various challenges. It is widely believed that not the constantly reduced blood flow, but rather the lack of regulation thereof, leads to prevalent ocular diseases. [source] An evidence-based approach to human dermatomesCLINICAL ANATOMY, Issue 5 2008M.W.L. Lee Abstract The dermatome is a fundamental concept in human anatomy and of major importance in clinical practice. There are significant variations in current dermatome maps in standard anatomy texts. The aim of this study was to undertake a systematic literature review of the available evidence for the distribution of human dermatomes. Particular emphasis was placed on the technique of ascertainment, the location and extent of each dermatome, the number of subjects studied, and methodologic limitations. Our findings demonstrate that current dermatome maps are inaccurate and based on flawed studies. After selecting the best available evidence, a novel evidence-based dermatome map was constructed. This represents the most consistent tactile dermatomal areas for each spinal dorsal nerve root found in most individuals. In addition to highlighting the orderly arrangement, areas of consistency and clinical usefulness of dermatomes, their overlap and variability deserve greater emphasis. This review demonstrates the validity of an evidence-based approach to an anatomical concept. Clin. Anat. 21:363,373, 2008. © 2008 Wiley-Liss, Inc. [source] Life-Cycle Performance of RC Bridges: Probabilistic ApproachCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 1 2000Dimitri V. Val This article addresses the problem of reliability assessment of reinforced concrete (RC) bridges during their service life. First, a probabilistic model for assessment of time-dependent reliability of RC bridges is presented, with particular emphasis placed on deterioration of bridges due to corrosion of reinforcing steel. The model takes into account uncertainties associated with materials properties, bridge dimensions, loads, and corrosion initiation and propagation. Time-dependent reliabilities are considered for ultimate and serviceability limit states. Examples illustrate the application of the model. Second, updating of predictive probabilistic models using site-specific data is considered. Bayesian statistical theory that provides a mathematical basis for such updating is outlined briefly, and its implementation for the updating of information about bridge properties using inspection data is described in more detail. An example illustrates the effect of this updating on bridge reliability. [source] Outcome of Pulmonary Valve Replacements in Adults after Tetralogy Repair: A Multi-institutional StudyCONGENITAL HEART DISEASE, Issue 3 2008Thomas P. Graham Jr. MD ABSTRACT Objective., The purpose of this study was to assess the outcome of pulmonary valve replacement (PVR) in adults with moderate/severe pulmonary regurgitation after tetralogy repair, with particular emphasis on patient outcome, durability of valve repair, and improvement in symptomatology. Design/Setting/Patients., The project committee of the International Society of Congenital Heart Disease undertook a retrospective multi-institutional analysis of PVR. Seven centers participated in submitting data on 93 patients >18 years of age who had the operation performed and follow-up obtained. The average age of PVR was 26± years (median 27 years). Time of follow-up after replacement was 3 years (range 4 days,28 years). Outcomes/Measures/Results., Kaplan,Meier estimates of durability of PVR showed approximately 50% replacement at 11 years. There were two deaths at 6 and 12 months after valve replacement. Right ventricular (RV) size estimated by echocardiography from pre- to postoperative studies decreased in 81% (P < 0.001 testing for equal proportions), but RV systolic function increased in only 36% (P = 0.09). Ability index improved in 59% (P < 0.001) and clinical heart failure status improved in 57% with this problem before PVR. PVR did not improve arrhythmia status in a small group of patients. Conclusions., PVR is associated with low mortality, decrease in RV size and improvement in ability index, and uncertain effects on RV systolic function. Average valve durability was approximately 11 years. Criteria for PVR that will preserve RV function are not clearly identified, and management of these patients remains a difficult enterprise. [source] | |||||||||||||||||||||||||||||||||||||||||||