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Different Approaches (different + approach)
Selected AbstractsTHE NEW INSTITUTIONAL ECONOMICS , A DIFFERENT APPROACH TO ECONOMIC ANALYSISECONOMIC AFFAIRS, Issue 3 2008Eirik G. Furubotn The initial objective of the paper is to describe the way in which the term ,New Institutional Economics' (NIE) emerged in the literature and became the designation for a new field concerned with the study of various analytical techniques designed for the exploration of institutional phenomena. It is then shown how some of the more important of these techniques, transaction-cost economics, property-rights analysis and contract theory, have been applied in two central lines of neoinstitutional thought , the Williamsonian and the Northian. Criticisms of these two disparate theoretical positions on the NIE are considered and assessed. Next, a brief review of some of the empirical literature is undertaken so that the explanatory powers of NIE themes can be gauged. Finally, the paper offers a few general remarks on the present state of the NIE and its possible influence on the further development of economics. [source] Change the Analyst and Not the System: A Different Approach to Intelligence ReformFOREIGN POLICY ANALYSIS, Issue 2 2008Uri Bar-Joseph Recent intelligence failures, including first and foremost the mistaken estimate of Iraq's weapons of mass destruction (WMD) prior to the war, show that a prime source of such failures is the adherence by analysts to preconceptions (or mind-sets) which entail the rejection of new information that contradicts it. The source of this kind of problem lies in well known psychological mechanisms. Yet official investigations into intelligence blunders have typically ignored this problem or have not suggested an appropriate solution thus far. Our paper suggests an original approach based on the fact that certain types of personalities are more likely than others to fall victim to these biased judgments. Existing psychological tests can help determine individual susceptibility to such tendencies. Therefore we suggest that intelligence organizations should pay far more attention to these personality characteristics, especially an analyst's level of openness, in recruitment, training, and promotion. Such attention would help create more effective reforms in intelligence than organizational models which advocate "devil's advocate" kind of solutions. [source] Different Approaches to a Regional Search for Balance: The Johnson Administration, the State Department, and the Middle East, 1964,1967*DIPLOMATIC HISTORY, Issue 1 2008Arlene Lazarowitz First page of article [source] Beyond Multilingualism: On Different Approaches to the Handling of Diverging Language Versions of a Community LawEUROPEAN LAW JOURNAL, Issue 1 2010Theodor Schilling This article deals with a problem created by the EU's multilingualism, the fallibility of translators and the ruses of politicians: for different reasons, it is quite common that equally authentic language versions of a Community law have different meanings if taken on their own. While the ECJ's uniform interpretation approach to this problem, which must be seen as required under the non-discrimination principle, has permitted equitable results in those cases decided by the ECJ, it would not be adequate for the simplest type of case, ie that a citizen has every reason to trust her own language version of a law. In such a case, her legitimate expectations in the equal authenticity of that version requires protection. De lege lata the article therefore proposes, in the interest of generally equitable solutions, a balancing, in the individual case, of the protection of legitimate expectations and the non-discrimination principle. De lege ferenda it proposes a more radical solution, ie that there be only one authentic version of every Community law. [source] On Different Approaches to Estimate the Mass Fractal Dimension of Coal AggregatesPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 5 2005Jimmy Y. H. Liao Abstract Several methods to measure the structures of coal aggregates are compared. Loose and compact coal aggregates were generated through flocculation of ultrafine coal particles (mean volume diameter of 12,,m) under specific shearing conditions. Aggregate structure in terms of mass fractal dimension, Df, was determined using various methods; namely 2D and 3D image analysis, interpretation of intensity patterns from small angle light scattering, changes in aggregation state through light obscuration, and settling behavior. In this study, the measured values of Df ranged from 1.84,2.19 for coal aggregates with more open structures, and around 2.27,2.66 for the compact ones. All of these approaches could distinguish structural differences between aggregates, albeit with variation in Df values estimated by the different techniques. The discrepancy in the absolute values for fractal dimension is due to the different physical properties measured by each approach, depending on the assumptions used to infer Df from measurable parameters. In addition, image analysis and settling techniques are based on the examination of individual aggregates, such that a large number of data points are required to yield statistically representative estimations. Light scattering and obscuration measure the aggregates collectively to give average Df values of the particulate systems; consequently ignoring any structural variation between the aggregates, and leaving possible small contaminations undetected (e.g. by dust particles or air bubbles). Appropriate utilization of a particular method is thus largely determined by system properties and required data quality. [source] Hydrodynamic Cell Model: General Formulation and Comparative Analysis of Different ApproachesTHE CANADIAN JOURNAL OF CHEMICAL ENGINEERING, Issue 5 2007Emiliy K. Zholkovskiy Abstract This paper is concerned with the Cell Model method of addressing hydrodynamic flow through system of solid particles. The starting point of the analysis is the general problem formulation intended for describing a pressure driven flow through a diaphragm which can be considered as a set of representative cells having arbitrary shape and containing any number of particles. Using the general problem formulation, the hydrodynamic field inside an individual representative cell is interrelated with the applied pressure difference and the external flow velocity. To this end, four relationships containing integrals over the outer boundary of a representative cell are derived in the paper. Assuming that the representative cell is a sphere containing a single particle in the centre, the derived general relationships are transformed into outer cell boundary conditions employed in the literature by different authors. The general number of the obtained outer boundary conditions is more than the required number. Accordingly, by choosing different sets of the outer boundary conditions, different models are considered and compared with each other and with the results obtained by others for regular particle arrays. The common and different features of the hydrodynamic and electrodynamic versions of the Cell Model approaches are analyzed. Finally, it is discussed which version of the cell model gives the best approximation while describing pressure and electrically driven flows through a diaphragm and sedimentation of particles. On s'intéresse dans cet article à la méthode du Modèle de Cellules pour traiter l'écoulement à travers un système de particules solides. Le point de départ de l'analyse consiste à formuler le problème général dans le but de décrire un écoulement sous pression dans un diaphragme qui peut être considéré comme un ensemble de cellules représentatives de forme arbitraire et contenant un nombre quelconque de particules. À l'aide de cette formulation générale du problème, l'hydrodynamique dans une cellule représentative donnée est reliée à la différence de pression appliquée et à la vitesse d'écoulement externe. À cette fin, quatre relations contenant des intégrales sur la frontière d'une cellule représentative sont établies dans cette étude. Si l'on suppose que la cellule représentative est une sphère contenant une particule unique en son centre, les relations générales calculées peuvent être transformées en conditions à la frontière des cellules semblables à celles employées dans la littérature scientifique par différents auteurs. Le nombre général de conditions limites obtenues dépasse le nombre requis. Par conséquent, en choisissant différents ensembles de conditions limites, différents modèles sont considérés et comparés entre eux ainsi qu'avec les résultats obtenus pour des arrangements réguliers de particules. Les caractéristiques des versions hydrodynamiques et électrodynamiques des approches du Modèle de Cellules sont analysées. Finalement, on examine quelle version de modèle de cellule donne la meilleure approximation des écoulements sous pression et des écoulements électrodynamiques à travers un diaphragme et pour la sédimentation des particules. [source] NMR methods for studying membrane-active antimicrobial peptidesCONCEPTS IN MAGNETIC RESONANCE, Issue 2 2004Erik Strandberg Abstract NMR is a versatile tool for studying interactions between antimicrobial peptides and lipid membranes. Different approaches using both liquid state and solid state NMR are outlined here, with an emphasis on solid state NMR methods, to study the structures of antimicrobial peptides in lipid bilayers as well as the effect of these peptides on model membranes. Different NMR techniques for observing both peptides and lipids are explained, including 2H, 13C, 15N, and 19F labels, or natural abundance 1H, 13C, or 31P. Previous studies in the field are extensively reviewed in easily accessible tables. © 2004 Wiley Periodicals, Inc. Concepts Magn Reson 23A: 89,120, 2004. [source] Erythropoiesis-stimulating agents: development, detection and dangers,DRUG TESTING AND ANALYSIS, Issue 6 2009Stefan E. Franz Abstract Epoetin alfa, the first member of the family of erythropoiesis stimulating agents (ESAs), was introduced to the market in 1989. Since then development has progressed to epoetins of the third generation. Currently drugs that use alternative approaches to stimulate erythropoiesis are under development. Uptake of all available ESAs into doping has occurred rapidly after their introduction. A multitude of dangers to health are associated with the illicit use of these substances. Different approaches to detect ESAs in doping control have been developed to comply with the very diverse nature of the compounds used. Future developments in the field of ESA require the development of new techniques in doping analysis. This review gives an overview of the development of ESA and its detection methods as well as future developments. [Correction made here after initial online publication] Copyright © 2009 John Wiley & Sons, Ltd. [source] State of the Art in the Field of Electronic and Bioelectronic Tongues , Towards the Analysis of WinesELECTROANALYSIS, Issue 23 2009Jiri Zeravik Abstract This review compares various types of (bio)electronic tongues. The design and principles of potentiometric and voltammetric electronic tongues are discussed together with applications in food and environmental analysis. Different approaches towards bioelectronic tongue are presented. Several methods for evaluation and interpretation of the measured data are described. Finally, the potential of such devices for analysis of wine is discussed. [source] Molecular classification of borderline ovarian tumors using hierarchical cluster analysis of protein expression profilesINTERNATIONAL JOURNAL OF CANCER, Issue 6 2002Ayodele A. Alaiya Abstract Ovarian tumors range from benign to aggressive malignant tumors, including an intermediate class referred to as borderline carcinoma. The prognosis of the disease is strongly dependent on tumor classification, where patients with borderline tumors have much better prognosis than patients with carcinomas. We here describe the use of hierarchical clustering analysis of quantitative protein expression data for classification of this type of tumor. An accurate classification was not achieved using an unselected set of 1,584 protein spots for clustering analysis. Different approaches were used to select spots that were differentially expressed between tumors of different malignant potential and to use these sets of spots for classification. When sets of proteins were selected that differentiated benign and malignant tumors, borderline tumors clustered in the benign group. This is consistent with the biologic properties of these tumors. Our results indicate that hierarchical clustering analysis is a useful approach for analysis of protein profiles and show that this approach can be used for differential diagnosis of ovarian carcinomas and borderline tumors. © 2002 Wiley-Liss, Inc. [source] Properties of cell penetrating peptides (CPPs)IUBMB LIFE, Issue 1 2006Alexandre Kerkis Abstract Different approaches have been developed for the introduction of macromolecules, proteins and DNA into target cells. Viral (retroviruses, lentiviruses, etc.) and nonviral (liposomes, bioballistics etc.) vectors as well as lipid particles have been tested as DNA delivery systems. However, all of them share several undesirable effects that are difficult to overcome, such as unwanted immunoresponse and limited cell targeting. The discovery of the cell penetrating peptides (CPPs) showing properties of macromolecules carriers and enhancers of viral vectors, opened new opportunities for the delivery of biologically active cargos, including therapeutically relevant genes into various cells and tissues. This review summarizes recent data about the best characterized CPPs as well as those sharing cell-penetrating and cargo delivery properties despite differing in the primary sequence. The putative mechanisms of CPPs penetration into cells and interaction with intracellular structures such as chromosomes, cytoskeleton and centrioles are addressed. We further discuss recent developments in overcoming the lack of cells specificity, one of the main obstacles for CPPs application in gene therapy. In particular, we review a newly discovered affinity of CPPs to actively proliferating cells. IUBMB Life, 58: 7 - 13, 2006 [source] X-ray extinction changes due to dislocationsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 6 2007M. Masimov A correct interpretation of the diffraction phenomenon in crystals with low dislocation content, for which the kinematical scattering theory does not yield any reasonable results, was carried out by X-ray extinction treatments. Different approaches to investigating the dislocation-induced X-ray extinction changes are reviewed and the applicability of the statistical dynamical theory to analysis of the substructure characteristics of crystals is discussed. A relationship between the scattering amplitudes and the dislocation density in crystals is established by using pair correlation functions. A procedure for determination of the substructure characteristics by means of measurements of the integrated intensities is proposed. The tests illustrate satisfactory agreement of the investigated approaches with experimental data. [source] Is Atrial Fibrillation a Genetic Disease?JOURNAL OF CARDIOVASCULAR ELECTROPHYSIOLOGY, Issue 5 2005RAMON BRUGADA M.D. Atrial fibrillation remains one of the most challenging arrhythmias for the clinician and basic researcher. Different approaches have been undertaken to improve its understanding; from the development of animal models to the analysis of genetic backgrounds in individuals with familial and acquired forms of the disease. In the last few years, a large body of evidence has shown that alterations in ionic currents are involved in the disease. However, it has not been until recently, with the genetic link between mutations in proteins responsible for these ionic currents and the familial disease, that we have been given the final evidence that atrial fibrillation can also be primarily an ion channelopathy. Despite the limited prevalence of the inherited diseases, it has been shown before that the knowledge gained in their study will be helpful in dealing with the most common acquired forms of the disease. Therefore, as data keep unraveling, clinicians can expect that soon better therapeutic and preventive options for atrial fibrillation will emerge from basic science. [source] Noise propagation and error estimations in multivariate curve resolution alternating least squares using resampling methodsJOURNAL OF CHEMOMETRICS, Issue 7-8 2004Joaquim Jaumot Abstract Different approaches for the calculation of prediction intervals of estimations obtained in multivariate curve resolution using alternating least squares optimization methods are explored and compared. These methods include Monte Carlo simulations, noise addition and jackknife resampling. Obtained results allow a preliminary investigation of noise effects and error propagation on resolved profiles and on parameters estimated from them. The effect of noise on rotational ambiguities frequently found in curve resolution methods is discussed. This preliminary study is shown for the resolution of a three-component equilibrium system with overlapping concentration and spectral profiles. Copyright © 2004 John Wiley & Sons, Ltd. [source] Locally targeted initiatives to recruit and retain nurses in EnglandJOURNAL OF NURSING MANAGEMENT, Issue 4 2006DINAH GOULD BSc MPhil PhD RGN RNT Aim, The aim of this study is to provide a detailed account of the locally targeted strategies to improve staffing levels by senior nurses responsible for recruitment and retention in acute trusts in the National Health Service in England. Background, There is a shortfall in nursing numbers throughout England. Some trusts have employed senior nurses with a specific remit to improve recruitment and retention, but little has been published about their work or its success. Methods, Data were collected by telephone using semi-structured interviews with standard probes. The tape-recorded interview data were transcribed verbatim and analysed by content. Results, Of the 156 acute trusts in England, 36 employed a senior nurse to deal with recruitment and retention. Twenty-nine were interviewed. All were using a range of locally targeted initiatives to attract and retain health-care assistants, newly qualified and more experienced practitioners. They also worked closely with university staff to attract and retain student nurses who would later seek employment locally. Different approaches were used to secure the services of different types of staff. Conclusion, This exploratory study has revealed a wealth of valuable data concerning locally targeted recruitment and retention strategies. Further research is needed to examine the effectiveness and cost-effectiveness of the initiatives described. [source] Synthesis and properties of dendritic polymers based on natural amino acidsMACROMOLECULAR SYMPOSIA, Issue 1 2003Alexander Bilibin Abstract Different approaches, including polycondensation, polymerization, polymer analog condensation, and ionic binding have been investigated for synthesis of amino acid-based dendritic polymers. It was shown that a growth of dendrons generation prevents obtaining of products with high polymerization degree in polycondensation and polymerization procedures. In polymer analog condensation a growth of dendrons generation leads to considerable decrease of polymer analog reaction rate as well as substitution degree. Degree of ionic binding depends on a strength of ionogenic groups and dendrns generation. [source] Mitochondria-targeted disruptors and inhibitors of cytochrome c/cardiolipin peroxidase complexes: A new strategy in anti-apoptotic drug discoveryMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 1 2009Valerian E. Kagan Abstract Thre critical role of mitochondria in programmed cell death leads to the design of mitochondriotropic agents as a strategy in regulating apoptosis. For anticancer therapy, stimulation of proapoptotic mitochondrial events in tumor cells and their suppression in surrounding normal cells represents a promising paradigm for new therapies. Different approaches targeting regulation of components of mitochondrial antioxidant system such as Mn-SOD demonstrated significant antitumor efficiency, particularly in combination therapy. This review is focused on a newly discovered early stage of mitochondria-dependent apoptosis , oxidative lipid signaling involving a mitochondria-specific phospholipid cardiolipin (CL). Cytochrome c (cyt c) acts as a CL-specific peroxidase very early in apoptosis. At this stage, the hostile events are still secluded within the mitochondria and do not reach the cytosolic targets. CL oxidation process is required for the release of pro-apoptotic factors into the cytosol. Manipulation of cyt c interactions with CL, inhibition of peroxidase activity, and prevention of CL peroxidation are prime targets for the discovery of anti-apoptotic drugs acting before the "point-of-no-return" in the fulfillment of the cell death program. Therefore, mitochondria-targeted disruptors and inhibitors of cyt c/CL peroxidase complexes and suppression of CL peroxidation represent new strategies in anti-apoptotic drug discovery. [source] Practice development: purpose, methodology, facilitation and evaluationNURSING IN CRITICAL CARE, Issue 1 2003Kim Manley Summary ,Different approaches to practice development are associated with different assumptions, and these need to be made explicit if practice development is to be transparent, rigorous and systematic in its intentions and approaches ,A practice development methodology underpinned by critical social science is advocated because it focuses on achieving sustainable change through practitioner enlightenment, empowerment and emancipation and an associated culture, rather than focusing only on technical practice development ,Implications of different worldviews about practice development for facilitation and outcome evaluation are highlighted ,Emancipatory practice development underpinned by critical social science is argued as synonymous to emancipatory action research [source] Assessing the contribution of working conditions to socioeconomic disparities in health: A commentaryAMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 2 2010Paul A. Landsbergis PhD Abstract Introduction Occupational health researchers can play a pivotal role in increasing our understanding of the role of physical and psychosocial working conditions in producing socioeconomic health disparities and trends of increasing socioeconomic health disparities, contributing to interventions to reduce such disparities, and helping to improve public education materials on this subject. However, a number of methodological challenges in this field need to be considered. Methods Commentary, including a review of selected studies. Results/Conclusion Research needs to be guided by models of the associations between social (socioeconomic position (SEP), race/ethnicity, immigration status, and gender) and occupational variables and health, to avoid inappropriate control for confounding, and to specify causal pathways (mediation) and interaction effects. Different approaches to the theory and measurement of SEP also need to be tested. Am. J. Ind. Med. 53:95,103 2010. © 2009 Wiley-Liss, Inc. [source] Experimental charge-density study of paracetamol , multipole refinement in the presence of a disordered methyl groupACTA CRYSTALLOGRAPHICA SECTION A, Issue 6 2009Joanna M. B A high-resolution single-crystal X-ray study of paracetamol has been performed at 85,K. Different approaches to modeling the experimental electron density (ED) were tested for the dynamically disordered portions of the molecule in order to check to what extent it is possible to obtain a proper ED distribution in the ordered part. Models were examined in which the methyl-group ED was built from pseudoatoms taken from the University at Buffalo Pseudoatom Databank or the Invariom database, with multipole parameters for the remaining atoms being obtained from free refinement. The ,, restricted multipolar model (KRMM) and free ,, refinements were compared; restriction of the ,, parameters was essential in order to obtain values of the electrostatic interaction energy consistent with the results of theoretical single-point periodic calculations. After simultaneous use of KRMM refinement and the databases to model the methyl group, the bond critical point properties and interaction electrostatic energy values were found to be closer to those obtained from theory. Additionally, some discrepancies in the ED distribution and dipole moment among transferred aspherical atom model refinements utilizing both theoretical databases and parameters from theoretical periodic calculations are shown. Including the influence of the crystal field in the periodic calculations increases the ED in the hydroxyl and amide groups, thus leading to higher values of the electrostatic interaction energy, changes in the electrostatic potential values mapped on the isodensity surface and changes in the shape of the anisotropic displacement parameters with respect to results found for both database models. [source] Microbial bio-production of a recombinant stimuli-responsive biosurfactantBIOTECHNOLOGY & BIOENGINEERING, Issue 1 2009W. Kaar Abstract Biosurfactants have been the subject of recent interest as sustainable alternatives to petroleum-derived compounds in areas ranging from soil remediation to personal and health care. The production of naturally occurring biosurfactants depends on the presence of complex feed sources during microbial growth and requires multicomponent enzymes for synthesis within the cells. Conversely, designed peptide surfactants can be produced recombinantly in microbial systems, enabling the generation of improved variants by simple genetic manipulation. However, inefficient downstream processing is still an obstacle for the biological production of small peptides. We present the production of the peptide biosurfactant GAM1 in recombinant E. coli. Expression was performed in fusion to maltose binding protein using chemically defined minimal medium, followed by a single-step affinity capture and enzymatic cleavage using tobacco etch virus protease. Different approaches to the isolation of peptide after cleavage were investigated, with special emphasis on rapid and simple procedures. Solvent-, acid-, and heat-mediated precipitation of impurities were successfully applied as alternatives to post-cleavage chromatographic peptide purification, and gave peptide purities exceeding 90%. Acid precipitation was the method of choice, due to its simplicity and the high purification factor and recovery rate achieved here. The functionality of the bio-produced peptide was tested to ensure that the resulting peptide biosurfactant was both surface active and able to be triggered to switch between foam-stabilizing and foam-destabilizing states. Biotechnol. Bioeng. 2009;102: 176,187. © 2008 Wiley Periodicals, Inc. [source] Anaplastic large cell lymphoma treated with a leukemia-like therapyCANCER, Issue 10 2005Oncology (AIEOP) LNH-92 protocol, Report of the Italian Association of Pediatric Hematology Abstract BACKGROUND Childhood anaplastic large cell lymphoma (ALCL) is a well defined entity with a rather poor prognosis. Different approaches have been adopted in the treatment of ALCL in various cooperative trials, including short high-dose intensive therapy and leukemia-like protocols. In the early 1990s, the Italian Association of Pediatric Hematology and Oncology (AIEOP) initiated a multicenter trial for the treatment of ALCL based on a modified LSA2-L2 protocol. METHODS Thirty-four consecutive eligible children with newly diagnosed ALCL were enrolled in the AIEOP LNH-92 protocol. Treatment was comprised of an induction of remission phase, followed by consolidation and maintenance for a total duration of 24 months, independently of disease stage. RESULTS Thirty of 34 patients (88%) achieved complete disease remission and 8 patients experienced disease recurrence. With a median follow-up of 8.4 years, the probabilities of survival and event-free survival were 85% (range, 79,91%) and 65% (range, 57,73%), respectively. Therapy was well tolerated and hematologic toxicity was the most frequent toxicity. CONCLUSIONS The leukemia-like protocol AIEOP LNH-92 was found to be an effective treatment for childhood ALCL. Its long duration may be beneficial to specific patient subgroups, but optimal treatment duration in ALCL remains to be elucidated. Cancer 2005. © 2005 American Cancer Society. [source] Mikrowellen- und Mikrowellen-Vakuumtrocknung von LebensmittelnCHEMIE-INGENIEUR-TECHNIK (CIT), Issue 4 2004M. Regier Dr.-Ing. Abstract Die Verfahren der Mikrowellen- und Mikrowellen-Vakuumtrocknung von Lebensmitteln werden näher beleuchtet. Ausgehend von einigen historischen Bemerkungen zur Entwicklung von Mikrowellen-Erwärmungsverfahren werden die physikalischen Grundlagen, d.,h. Elektromagnetismus, Wärme- und Stofftransport, anhand der bei diesen Prozessen wichtigsten physikalischen Stoffeigenschaften beschrieben. Darauf aufbauend wird gezeigt, welche Ansatzpunkte zur Beschreibung und Modellierung von Mikrowellenverfahren in der Literatur existieren. Nach einer Klassifikation industrieller Mikrowellentrockner werden Beispiele für heutige Anwendungen der Mikrowellentrocknung beschrieben. Die Literaturhinweise sollen Interessierten auch als Ausgangspunkt zur Recherche weitergehender Informationen zu Mikrowellentrocknungsverfahren dienen. Microwave- and Microwave Vacuum-drying of Food Microwave- and microwave vacuum-drying processes for the drying of food are described. Starting with some historical remarks on the development of thermal microwave processes, the physical basics of electromagnetism, heat- and mass transfer as well as the important physical properties are specified. Different approaches for the physical description and modeling of microwave processes which are found in literature are shown. After a classifying of industrial microwave dryers some examples of today's microwave drying applications are depicted. The paper should also be a starting point for researchers being interested in detail information on microwave drying applications. [source] Ridge alterations following tooth extraction with and without flap elevation: an experimental study in the dogCLINICAL ORAL IMPLANTS RESEARCH, Issue 6 2009Mauricio G. Araújo Abstract Background: Different approaches were advocated to preserve or improve the dimension and contour of the ridge following tooth extraction. In some of studies, socket ,flapless extraction' apparently had a successful outcome. Aim: The objective of the present experiment was to compare hard tissue healing following tooth extraction with or without the prior elevation of mucosal full-thickness flaps. Material and methods: Five mongrel dogs were used. The two second mandibular premolars (2P2) were hemi-sected. The mesial roots were retained. By random selection the distal root in one side was removed after the elevation of full-thickness flaps while on the contralateral side, root extraction was performed in a flapless procedure. The soft tissue wound was closed with interrupted sutures. After 6 months of healing, the dogs were euthanized and biopsies were sampled. From each experimental site, four ground sections , two from the mesial root and two from the healed socket , were prepared, stained and examined in the microscope. Results: The data showed that the removal of a single tooth (root) during healing caused a marked change in the edentulous ridge. In the apical and middle portions of the socket site minor dimensional alterations occurred while in the coronal portion of the ridge the reduction of the hard tissue volume was substantial. Similar amounts of hard tissue loss occurred during healing irrespective of the procedure used to remove the tooth was, i.e. flapless or following flap elevation. Conclusion: Tooth loss (extraction) resulted in marked alterations of the ridge. The size of the alveolar process was reduced. The procedure used for tooth extraction , flapless or following flap elevation , apparently did not influence the more long-term outcome of healing. [source] Initialization Strategies in Simulation-Based SFE Eigenvalue AnalysisCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 5 2005Song Du Poor initializations often result in slow convergence, and in certain instances may lead to an incorrect or irrelevant answer. The problem of selecting an appropriate starting vector becomes even more complicated when the structure involved is characterized by properties that are random in nature. Here, a good initialization for one sample could be poor for another sample. Thus, the proper eigenvector initialization for uncertainty analysis involving Monte Carlo simulations is essential for efficient random eigenvalue analysis. Most simulation procedures to date have been sequential in nature, that is, a random vector to describe the structural system is simulated, a FE analysis is conducted, the response quantities are identified by post-processing, and the process is repeated until the standard error in the response of interest is within desired limits. A different approach is to generate all the sample (random) structures prior to performing any FE analysis, sequentially rank order them according to some appropriate measure of distance between the realizations, and perform the FE analyses in similar rank order, using the results from the previous analysis as the initialization for the current analysis. The sample structures may also be ordered into a tree-type data structure, where each node represents a random sample, the traverse of the tree starts from the root of the tree until every node in the tree is visited exactly once. This approach differs from the sequential ordering approach in that it uses the solution of the "closest" node to initialize the iterative solver. The computational efficiencies that result from such orderings (at a modest expense of additional data storage) are demonstrated through a stability analysis of a system with closely spaced buckling loads and the modal analysis of a simply supported beam. [source] 10-year prevalence of contact allergy in the general population in Denmark estimated through the CE-DUR methodCONTACT DERMATITIS, Issue 4 2007Jacob Pontoppidan Thyssen The prevalence of contact allergy in the general population has traditionally been investigated through population-based epidemiological studies. A different approach is the combination of clinical epidemiological (CE) data and the World Health Organization-defined drug utilization research (DUR) method. The CE-DUR method was applied in Denmark to estimate the prevalence of contact allergy in the general population and compare it with the prevalence estimates from the Glostrup allergy studies. Contact allergy prevalence estimates ranging from very liberal (,worst case') to conservative (,best case') assumptions were based on patch test reading data in combination with an estimate of the number of persons eligible for patch testing each year based on sales data of the ,standard series'. The estimated 10-year prevalence of contact allergy ranged between 7.3% and 12.9% for adult Danes older than 18 years. The 10-year prevalence of contact allergy measured by CE-DUR was slightly lower than previous prevalence estimates from the Glostrup allergy studies. This could probably be explained by a decrease in nickel allergy. The CE-DUR approach holds the potential of being an efficient and easy monitoring method of contact allergy prevalence. [source] The cost of diabetes: time for a different approach?DIABETIC MEDICINE, Issue 12 2000S. Dixon No abstract is available for this article. [source] An evidence-based approach to equine parasite control: It ain't the 60s anymoreEQUINE VETERINARY EDUCATION, Issue 6 2010R. M. Kaplan Summary Most veterinarians continue to recommend anthelmintic treatment programmes for horses that derive from knowledge and concepts more than 40 years old. However, much has changed since these recommendations were first introduced and current approaches routinely fail to provide optimal or even adequate levels of parasite control. There are many reasons for this. Recent studies demonstrate that anthelmintic resistance in equine parasites is highly prevalent and multiple-drug resistance is common in some countries, but few veterinarians take this into account when making treatment decisions or when recommending rotation of anthelmintics. Furthermore, the current approach of treating all horses at frequent intervals was designed specifically to control the highly pathogenic large strongyle, Strongylus vulgaris. But this parasite is now quite uncommon in managed horses in most of the world. Presently, the cyathostomins (small strongyles) are the principal parasitic pathogens of mature horses. The biology and pathogenesis of cyathostomins and S. vulgaris are very different and therefore require an entirely different approach. Furthermore, it is known that parasites are highly over-dispersed in hosts, such that a small percentage of hosts harbour most of the parasites. The common practices of recommending the same treatment programme for all horses despite great differences in parasite burdens, recommending prophylactic treatment of all horses without indication of parasitic disease or knowing what species of parasites are infecting the horses, recommending use of drugs without knowledge of their efficacy and failing to perform diagnostic (faecal egg count) surveillance for estimating parasite burdens and determining treatment efficacy, are all incompatible with current standards of veterinary practice. Consequently, it is necessary that attitudes and approaches to parasite control in horses undergo a complete overhaul. This is best achieved by following an evidence-based approach that takes into account all of these issues and is based on science, not tradition. [source] Complete correlation, detection loophole and Bell's theoremFORTSCHRITTE DER PHYSIK/PROGRESS OF PHYSICS, Issue 1 2005A. Shafiee Two new formulations of Bell's theorem are given here. First, we consider a definite set of two entangled photons with only two polarization directions, for which Bell's locality assumption is violated for the case of perfect correlation. Then, using a different approach, we prove an efficient Bell-type inequality which is violated by some quantum mechanical predictions, independent of the efficiency factors. [source] Functional connexin "hemichannels": A critical appraisalGLIA, Issue 7 2006David C. Spray Abstract "Hemichannels" are defined as the halves of gap junction channels (also termed connexons) that are contributed by one cell; "hemichannels" are considered to be functional if they are open in nonjunctional membranes in the absence of pairing with partners from adjacent cells. Several recent reviews have summarized the blossoming literature regarding functional "hemichannels", in some cases encyclopedically. However, most of these previous reviews have been written with the assumption that all data reporting "hemichannel" involvement really have studied phenomena in which connexons actually form the permeability or conductance pathway. In this review, we have taken a slightly different approach. We review the concept of "hemichannels", summarize properties that might be expected of half gap junctions and evaluate the extent to which the properties of presumptive "hemichannels" match expectations. Then we consider functions attributed to hemichannels, provide an overview of other channel types that might fulfill similar roles and provide sets of criteria that might be applied to verify involvement of connexin hemichannels in cell and tissue function. One firm conclusion is reached. The study of hemichannels is technically challenging and fraught with opportunities for misinterpretation, so that future studies must apply rigorous standards for detection of hemichannel expression and function. At the same time there are reasons to expect surprises, including the possibility that some time honored techniques for studying gap junctions may prove unsuitable for detecting hemichannels. We advise hemichannel researchers to proceed with caution and an open mind. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||