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Selected AbstractsSORTAL ANAPHORA RESOLUTION IN MEDLINE ABSTRACTSCOMPUTATIONAL INTELLIGENCE, Issue 1 2007Manabu Torii This paper reports our investigation of machine learning methods applied to anaphora resolution for biology texts, particularly paper abstracts. Our primary concern is the investigation of features and their combinations for effective anaphora resolution. In this paper, we focus on the resolution of demonstrative phrases and definite determiner phrases, the two most prevalent forms of anaphoric expressions that we find in biology research articles. Different resolution models are developed for demonstrative and definite determiner phrases. Our work shows that models may be optimized differently for each of the phrase types. Also, because a significant number of definite determiner phrases are not anaphoric, we induce a model to detect anaphoricity, i.e., a model that classifies phrases as either anaphoric or nonanaphoric. We propose several novel features that we call highlighting features, and consider their utility particularly for processing paper abstracts. The system using the highlighting features achieved accuracies of 78% and 71% for demonstrative phrases and definite determiner phrases, respectively. The use of the highlighting features reduced the error rate by about 10%. [source] Effect of redundancy on the mean time to failure of wireless sensor networksCONCURRENCY AND COMPUTATION: PRACTICE & EXPERIENCE, Issue 8 2007Anh Phan Speer Abstract In data-driven wireless sensor networks (WSNs), the system must perform data sensing and retrieval and possibly aggregate data as a response at runtime. As a WSN is often deployed unattended in areas where replacements of failed sensors are difficult, energy conservation is of primary concern. While the use of redundancy is desirable in terms of satisfying user queries to cope with sensor and transmission faults, it may adversely shorten the lifetime of the WSN, as more sensor nodes will have to be used to answer queries, causing the energy of the system to drain quickly. In this paper, we analyze the effect of redundancy on the mean time to failure (MTTF) of a WSN in terms of the number of queries the system is able to answer correctly before it fails due to either sensor/transmission faults or energy depletion. In particular, we analyze the effect of redundancy on the MTTF of cluster-structured WSNs for energy conservations. We show that a tradeoff exists between redundancy and MTTF. Furthermore, an optimal redundancy level exists such that the MTTF of the system is maximized. Copyright © 2007 John Wiley & Sons, Ltd. [source] MODEL MISSPECIFICATION: WHY AGGREGATION OF OFFENSES IN FEDERAL SENTENCING EQUATIONS IS PROBLEMATICCRIMINOLOGY, Issue 4 2003CELESTA A. ALBONETTI This paper addresses two concerns that arise from Steffensmeier and Demuth (2001) analysis of federal sentencing and their misrepresentation of my analyses of sentence severity (Albonetti, 1997). My primary concern is to alert researchers to the importance of controlling for the guidelines offense that drives the sentencing process under the Federal Sentencing Guidelines. My second concern is to correct Steffensmeier and Demuth's (2001) errors in interpretation of my earlier findings of the effect of guidelines offense severity on length of imprisonment. [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] Global climate patterns explain range-wide synchronicity in survival of a migratory seabirdGLOBAL CHANGE BIOLOGY, Issue 1 2009STEPHANIE JENOUVRIER Abstract To predict the impact of climate change over the whole species distribution range, comparison of adult survival variations over large spatial scale is of primary concern for long-lived species populations that are particularly susceptible to decline if adult survival is reduced. In this study, we estimated and compared adult survival rates between 1989 and 1997 of six populations of Cory's shearwater (Calonectris diomedea) spread across 4600 km using capture,recapture models. We showed that mean annual adult survival rates are different among populations along a longitudinal gradient and between sexes. Variation in adult survival is synchronized among populations, with three distinct groups: (1) both females and males of Corsica, Tremiti, and Selvagem (annual survival range 0.88,0.96); (2) both females and males of Frioul and females from Crete (0.82,0.92); and (3) both females and males of Malta and males from Crete (0.74,0.88). The total variation accounted for by the common pattern of variation is on average 71%, suggesting strong environmental forcing. At least 61% of the variation in survival is explained by the Southern Oscillation Index fluctuations. We suggested that Atlantic hurricanes and storms during La Niña years may increase adult mortality for Cory's shearwater during winter months. For long-lived seabird species, variation in adult survival is buffered against environmental variability, although extreme climate conditions such as storms significantly affect adult survival. The effect of climate at large spatial scales on adult survival during the nonbreeding period may lead to synchronization of variation in adult survival over the species' range and has large effects on the meta-population trends. One can thus worry about the future of such long-lived seabirds species under the predictions of higher frequency of extreme large-scale climatic events. [source] Fully stressed frame structures unobtainable by conventional design methodologyINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN ENGINEERING, Issue 12 2001Keith M. Mueller Abstract A structure is said to be fully stressed if every member of the structure is stressed to its maximum allowable limit for at least one of the loading conditions. Fully stressed design is most commonly used for small and medium size frames where drift is not a primary concern. There are several potential methods available to the engineer to proportion a fully stressed frame structure. The most commonly used methods are those taught to all structural engineering students and are very easy to understand and to implement. These conventional methods are based on the intuitive idea that if a member is overstressed, it should be made larger. If a member is understressed, it can be made smaller, saving valuable material. It has been found that a large number of distinct fully stressed designs can exist for a single frame structure subjected to multiple loading conditions. This study will demonstrate that conventional methods are unable to converge to many, if not most, of these designs. These unobtainable designs are referred to as ,repellers' under the action of conventional methods. Other, more complicated methods can be used to locate these repelling fully stressed designs. For example, Newton's method can be used to solve a non-linear system of equations that defines the fully stressed state. However, Newton's method can be plagued by divergence and also by convergence to physically meaningless solutions. This study will propose a new fully stressed design technique that does not have these problems. Copyright © 2001 John Wiley & Sons, Ltd. [source] The harmonic adjoint approach to unsteady turbomachinery designINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN FLUIDS, Issue 3-4 2002M. C. Duta Abstract In recent years, there has been rapid progress in aerodynamic optimization methods which use adjoint flow analysis to efficiently calculate the sensitivity of steady-state objective functions to changes in the underlying design variables. This paper shows that the same adjoint approach can be used in turbomachinery applications in which the primary concern is blade vibration due to harmonic flow unsteadiness. The paper introduces the key engineering concepts and discusses the derivation of the adjoint analysis at the algebraic level. The emphasis is on the algorithmic aspects of the analysis, on the iterative solution method and on the role played by the strong solid wall boundary condition, in particular. The novel ideas are exploited to reveal the potential of the approach in the minimization of the unsteady vibration of turbomachinery blades due to incident wakes. Copyright © 2002 John Wiley & Sons, Ltd. [source] Building and Contesting Neoliberalism at the Local Level: Reflections on the Symposium and on Recent Experience in BoliviaINTERNATIONAL JOURNAL OF URBAN AND REGIONAL RESEARCH, Issue 1 2010MIKE GEDDES Abstract This final article first reflects on the previous articles in the symposium, positioning the diverse trajectories of local governance which they exhibit in relation to two contrasting ideal types , the one neoliberal, the other contesting neoliberalism from a progressive, left perspective. Differences between these ideal types, and among the actually existing patterns of local governance discussed in the symposium (in relation to their economic and social objectives and governance institutions and practices) are highlighted. The second part of the article offers a consideration of local governance in Bolivia, a country which encapsulates some of the key issues at stake in the ongoing struggles to either build, or contest, neoliberalism at the local level. Here a distinction is advanced between ,expansive' and ,consolidatory' moments of neoliberal local governance, which may take the form of consecutive phases, but may have different, overlapping temporalities. In conclusion, it is suggested the challenges which the impact of the financial crisis and global recession pose both to neoliberal forms of local governance and to contestatory forces should be a primary concern for future research. Résumé Ce dernier article revient d'abord sur les articles précédents du symposium, pour replacer les diverses voies de gouvernance locale présentées par rapport à deux idéaltypes mis en opposition: l'un néolibéral, l'autre contestant le néolibéralisme d'un point de vue progressiste de gauche. Il met en évidence les différences entre ces idéaltypes, et entre les modèles actuels de gouvernance locale débattus dans le symposium (en lien avec leurs objectifs économiques et sociaux et avec les institutions et pratiques de gouvernance). La seconde partie s'intéresse à la gouvernance locale en Bolivie, un pays qui incarne certains des principaux enjeux dans les luttes en cours visant à bâtir ou à contester un néolibéralisme au niveau local. Une distinction est proposée entre les moments d',expansion' et de ,consolidation' de la gouvernance locale néolibérale, lesquels peuvent se présenter de manière consécutive, mais aussi sur des plages temporelles différentes en chevauchement. Pour conclure, les défis que les conséquences de la crise financière et la récession mondiale posent aux formes néolibérales de gouvernance locale ainsi qu'aux forces contestataires devraient constituer une priorité dans les recherches à venir. [source] Bioethics and the Samoan indigenous referenceINTERNATIONAL SOCIAL SCIENCE JOURNAL, Issue 195 2009Tupua Tamasese Ta'isi Efi Tui Atua Bioethical questions are of primary concern to science, religion and traditional or indigenous knowledge. What the indigenous reference can offer the world is a re-appreciation of the rightful place of the spiritual, sacred and tapu (implicit in indigenous cultural rituals) in ethical debates. This article explores what might be the ethical in the Samoan indigenous reference. Two main indigenous Samoan concepts, tapu (the sacred) and tofa sa'ili (the search for wisdom), are considered and situated in contemporary Samoan experiences and understandings of the ethical. If ethics is about moral principles or values, these two Samoan concepts provide the basis for ethical research in a Samoan indigenous context. This article aims at providing a Samoan frame of reference to deliberate about universal codes for bioethical research and the nature of ethical research practice in the Pacific. [source] From Jerusalem to Baghdad?INTERNATIONAL STUDIES PERSPECTIVES, Issue 1 2009Israel, the War in Iraq The prevailing opinion that the Bush administration took the United States to war against Iraq in March 2003 under false pretenses has led many to believe that Israel's security was the secret rationale for the war. According to this "war for Israel" thesis, neoconservative policymakers in the Bush administration, the pro-Israel lobby in the United States, and Israel's government all pushed the United States to go to war with Iraq for the sake of Israel's security. This article critically assesses this controversial claim and examines Israel's role in the U.S. decision to invade Iraq. I argued that while neoconservatives were instrumental in promoting the Iraq war, Israel was not their primary concern and that although American Jewish organizations and the Israeli government did largely support the Iraq war, they did not seek it or actively lobby for it. [source] Perceptions of internal marketing and organizational commitment by nursesJOURNAL OF ADVANCED NURSING, Issue 1 2009Ching Sheng Chang Abstract Title.,Perceptions of internal marketing and organizational commitment by nurses. Aim., This paper is a report of a study to determine whether a favourable perception of internal marketing is associated with increased organizational commitment. Background., The role of nurses in healthcare treatment is expanding, and becoming more important as time progresses. Therefore, the primary concern of business of health care is to use internal marketing strategies effectively to enhance and develop nurses' organizational commitment and reduce turnover to promote competitive advantages for the organization. Methods., A cross-sectional design was used. Questionnaires were distributed in 2006 to a convenience sample of 450 Registered Nurses in two teaching hospitals in Taiwan, and 318 questionnaires were returned. Eighteen were excluded because of incomplete answers, which left 300 usable questionnaires (response rate 66·7%). Validity and reliability testing of the questionnaire proved satisfactory and Structural Equation Modeling was used to analyse the data. Results., A favourable perception of internal marketing was associated with increased organizational commitment. Communication management had the greatest influence on organizational commitment and external activity had the smallest impact. Conclusion., Hospital managers need to recognize the importance of internal marketing for staff retention and the survival of their organizations as competitive pressure increases. As a great deal of time and costs are involved in educating nurses, the best way to retain outstanding nurses and reduce turnover costs and personnel problems is for employers to understand the needs and expectations of their nursing staff. [source] Understanding the multiple meanings of ,inbreeding' and ,effective size' for genetic management of African rhinoceros populationsAFRICAN JOURNAL OF ECOLOGY, Issue 4 2009Stanton Braude Abstract Although some African rhinoceros populations are currently increasing, others are critically endangered. Even healthy populations are extensively managed in the wild and in captivity. While political and demographic considerations are of primary concern, many decisions are made in the name of genetic management. Such decisions should be informed by a full understanding of the multiple meanings of inbreeding and effective population size. In this essay, we examine inbreeding and effective size of wild and captive populations of African rhinoceroses. We conclude by showing how misunderstanding of effective size and Franklin's 50/500 rule can make a crucial difference in informing management decisions. Résumé Bien que certaines populations de rhinocéros africains soient actuellement en augmentation, d'autres sont en danger critique. Même les populations saines sont gérées très activement dans la nature et en captivité. Alors que les considérations politiques et démographiques soient les principaux motifs d'inquiétude, de nombreuses décisions sont prises au nom de la gestion génétique. Ces décisions devraient se faire en pleine connaissance des multiples implications de l'inbreeding et de ce qu'est une taille de population nécessaire. Dans cet essai, nous examinons l'inbreeding et la taille nécessaire des populations sauvages et captives de rhinocéros africains. Nous concluons en montrant comment une mauvaise compréhension de la taille nécessaire et de la règle 50/500 de Franklin peut entraîner une différence cruciale lorsqu'il s'agit de prendre, en connaissance de cause, les décisions opportunes. [source] Parental negotiations of the moral terrain of risk in relation to young people with intellectual disabilitiesJOURNAL OF COMMUNITY & APPLIED SOCIAL PSYCHOLOGY, Issue 4 2009Kathryn Almack Abstract This paper draws upon parental accounts from a study of the process of transition for a cohort of 28 young people with relatively severe intellectual disabilities who left special schools in 2004 and 2005 in two adjacent English localities. This paper examines how parents negotiate these boundaries and position themselves in relation to risk. A primary concern identified by parents during this transition period focuses on the risk of harm facing these vulnerable young people (whether through accidents or through sexual, emotional, physical or financial abuse) as they move into the adult world. These concerns are juxtaposed with discourses that increasingly promote the possibilities for people with intellectual disabilities to express and follow their own wishes and aspirations. For example, the policy agenda in England and Wales actively endorses the start of adult life as a time of opportunity for young people and promotes the values of independence and choice. In accounting for the management of risk in the young people's lives, we conclude that parents navigate complex boundaries between being seen to be over-protective and ,letting go'; between trusting others to act in the young adults' best interests and allowing these young people the autonomy to negotiate risk. Copyright © 2008 John Wiley & Sons, Ltd. [source] DETECTION OF SALMONELLA TYPHIMURIUM IN OYSTERS BY PCR AND MOLECULAR HYBRIDIZATIONJOURNAL OF FOOD QUALITY, Issue 5 2006A.A. CORRÊA ABSTRACT Because shellfish (oysters, clams and mussels) are filter feeders, i.e., able to concentrate pathogens from the surrounding waters within their tissues, they have been widely associated with outbreaks illness. The incidence of salmonellosis caused by the consumption of raw or undercooked shellfish, is a primary concern of public health agencies. Then, in recent years, more rapid and specific methods based on the DNA sequence of salmonella genes have been developed to detect low levels of pathogens in environmental and food samples. In this study, we developed a sensitive method to detect low levels of Salmonella typhimurium in oyster tissues (0.1 cfu/g). This methodology consisted of dissection of the gastrointestinal oyster tract, pre-enrichment of the samples in nonselective medium, DNA extraction and polymerase chain reaction followed by molecular hybridization using a digoxygenin-labeled amplicon-derived probe. These results can benefit the public health agencies and shellfish producers concerning microbiological and quality aspects of the commercial oyster production. [source] Influence of boreal forest succession and dead wood qualities on saproxylic beetlesAGRICULTURAL AND FOREST ENTOMOLOGY, Issue 1 2007Joshua M. Jacobs Abstract 1,Saproxylic insects, a functional group dominated by beetles, are dependent on dead or moribund trees as habitat elements. 2,Although there are few studies of saproxylic insects from the North American boreal zone, European studies demonstrate that forest harvest can lead to a biologically significant decrease in saproxylic beetle diversity. 3,We studied saproxylic beetles in the North American boreal mixedwood forest using flight intercept traps established on naturally dead and girdled trembling aspen and spruce trees along a successional gradient of undisturbed stands from deciduous to coniferous overstory trees. 4,Composition and diversity of beetle assemblages differed among forest successional types. 5,Snag age class was an important determinant of composition for saproxylic beetle assemblages. 6,Multivariate regression analysis of these data indicated that saproxylic beetles are responding to changes in coarse woody debris, and not to the relative densities of canopy tree species, although these variables are strongly correlated. 7,Coarse woody debris management should be a primary concern in forest management plans seeking to conserve saproxylic organisms and the critical ecosystem functions (i.e. nutrient cycling) in which they participate. [source] Self-Monitoring in Social Interaction: The Centrality of Self-AffectJOURNAL OF PERSONALITY, Issue 3 2006William Ickes ABSTRACT In this review, we examine the role of self-monitoring in social interaction. We first note that the presumed ease with which self-monitors adapt to new social contexts is more apparent than real, being the self-conscious outcome of (1) high self-monitors' preference for clearly defined situations, (2) their use of scripts regarding typical situations, (3) their ability to formulate effective plans of action before social encounters, and (4) their ability to use other people's behavior as a guide. We then examine the strong motive of high self-monitors to express and evoke high levels of positive affect in their interpersonal relationships. Two recent unstructured dyadic interaction studies lead us to argue that the primary concern of high self-monitors during social interaction is to regulate their own self-affect through effective impression management. In this sense, it really is the self that is closely monitored whenever self-monitoring processes influence social interaction. [source] Financial Intermediary Versus Production Approach to Efficiency of Marketing Distribution Systems and Organizational Structure of Insurance CompaniesJOURNAL OF RISK AND INSURANCE, Issue 3 2005Patrick L. Brockett An examination of the efficiency of the marketing distribution channel and organizational structure for insurance companies is presented from a framework that views the insurer as a financial intermediary rather than as a "production entity" which produces "value added" through loss payments. Within this financial intermediary approach, solvency can be a primary concern for regulators of insurance companies, claims-paying ability can be a primary concern for policyholders, and return on investment can be a primary concern for investors. These three variables (solvency, financial return, and claims-paying ability) are considered as outputs of the insurance firm. The financial intermediary approach acknowledges that interests potentially conflict, and the strategic decision makers for the firm must balance one concern versus another when managing the insurance company. Accordingly, we investigate the efficiency of insurance companies using data envelopment analysis (DEA) having as insurer output an appropriately selected (for the firm under investigation) combination of solvency, claims-paying ability, and return on investment as outputs. These efficiency evaluations are further examined to study stock versus mutual form of organizational structure and agency versus direct marketing arrangements, which are examined separately and in combination. Comparisons with the "value-added" or "production" approach to insurer efficiency are presented. A new DEA approach and interpretation is also presented. [source] Towards more empathic medical students: a medical student hospitalization experienceMEDICAL EDUCATION, Issue 6 2002Michael Wilkes Objective, We designed a curricular exercise intended to expose healthy medical students, near the end of their basic science training, to the experience of hospitalization. We attempted to assess how a standardized hospitalization, for medical students just about to start their clinical rotations, was experienced by student participants. Design, A qualitative observational design was used, both to explore the perceptions of the hospitalized students and to generate hypotheses for further exploration. Setting, University and affiliated hospitals. Participants, Second-year medical students, towards the end of their basic science training. Outcome measures, Qualitative assessment of hospitalization experience. Results, Among key themes expressed by student participants were the following: they felt a profound loss of privacy; they found the nursing staff to be caring, attentive and professional, and repeatedly commented about how much time the nurses took to talk and listen to them and to take a complete history; in contrast they were particularly upset about the distance and coldness they felt from the medical staff; they expect this experience to affect their own future practice as physicians. When asked how this might change their attitudes in the future, students' comments generally reflected a primary concern with improving the human aspects of the patient experience. Conclusions, Student participants in a standardized inpatient hospitalization generally experienced strong feelings about issues of privacy, and about interactions with medical and nursing staff, which they expect to have an important impact on their own professional development. [source] Rethinking Ancient Maya Social Organization: Replacing "Lineage" with "House"AMERICAN ANTHROPOLOGIST, Issue 3 2000Susan D. Gillespie Long-standing disagreements concerning prehispanic Maya kinship and social organization have focused on the nature of their corporate groups, generally presumed to have been lineages. Specific debates center on whether the lineages were patrilineal or incorporated some kind of double-descent reckoning, how descent was combined with locality to define a group, and the status of lineage-outsiders within a group. It is argued here that Maya social organization is better approached within the contemporary critique of kinship, replacing "lineage" with Lévi-Strauss's model of the "house",a corporate group maintaining an estate perpetuated by the recruitment of members whose relationships are expressed "in the language" of kinship and affinity and affirmed by purposeful actions. In this perspective, the operation of corporate groups is the primary concern, and relationships construed in terms of consanguinity and affinity are seen as strategies pursued to enhance and perpetuate the group, [ancestor veneration, house society, kinship, Maya, social organization] [source] Radbruch and Hart on the Grudge Informer: A ReconsiderationRATIO JURIS, Issue 2 2002Thomas Mertens Hart's defense of the separation of law and morality is partly based on his refusal to accept Radbruch's solution of the well-known grudge informer case, in his famous article "Statutory Injustice and Suprastatutory Law." In this paper, I present a detailed reconstruction of the "debate" between Radbruch and Hart on this case. I reach the conclusion that Hart fails to address the issue that was Radbruch's primary concern, namely the legal position of the judiciary when dealing with criminal statutes. I suggest that Hart's separation thesis cannot be upheld in the face of this concern. In my argument, Hart's mistaken understanding of the verdict of the Oberlandesgericht Bamberg that he refers to plays a crucial role. [source] Anesthesia-Related Complications in Living Liver Donors: The Experience from One Center and the Reporting of One DeathAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2008S. Ozkardesler Living donor liver transplantation has become an alternative therapy for patients with end-stage liver disease. Donors are healthy individuals and donor safety is the primary concern. The objective of this study was to evaluate the anesthetic complications and outcomes for our donor cases; we report one death. The charts of the patients who underwent donor hepatectomy from February 1997 to June 2007 were retrospectively reviewed. Right hepatectomy (resection of segments 5,8) was done in 101 donors, left lobectomy (resection of segments 2,3) in 11 donors, and left hepatectomy (resection of segments 2,4) in one donor. Minor anesthetic complications were shoulder pain, pruritus and urinary retention related to epidural morphine, and major morbidity included central venous catheter-induced thrombosis of the brachial and subclavian vein, neuropraxia, foot drop and prolonged postdural puncture headache. One of 113 donors died from pulmonary embolism on the 11th postoperative day. This procedure has some major risks related to anesthesia and surgery. Although careful attention will lower complication rate, we have to keep in mind that the risks of donor surgery will not be completely eliminated. [source] COMMERCIAL ACTIVITY AS INSURANCE: THE INVESTMENT BEHAVIOUR OF NON-PROFIT ORGANIZATIONSANNALS OF PUBLIC AND COOPERATIVE ECONOMICS, Issue 3 2010John Bennett ABSTRACT,:,We provide a new explanation for commercial activities by non-profit organizations whose primary concern is to supply mission output. Starting from the observation that donations to individual non-profits are often highly volatile, we show how investment in commercial activity can constitute a form of insurance for mission activity. Although investment in commercial activity has an opportunity cost in terms of capacity to produce mission output, if donations turn out to be low the commercial revenue will enable cross-subsidization of mission output. The equilibrium commercial investment is (weakly) positively related to the degree of risk aversion. [source] Load transfer characteristics of unilateral distal extension removable partial dentures with polyacetal resin supporting componentsAUSTRALIAN DENTAL JOURNAL, Issue 1 2009T Jiao Abstract Background:, To photoelastically examine load transfer by unilateral distal extension removable partial dentures with supporting and retentive components made of the lower stiffness polyacetal resins. Methods:, A mandibular photoelastic model, with edentulous space distal to the right second premolar and missing the left first molar, was constructed to determine the load transmission characteristics of a unilateral distal extension base removable partial denture. Individual simulants were used for tooth structure, periodontal ligament, and alveolar bone. Three designs were fabricated: a major connector and clasps made from polyacetal resin, a metal framework as the major connector with polyacetal resin clasp and denture base, and a traditional metal framework I-bar removable partial denture. Simulated posterior bilateral and unilateral occlusal loads were applied to the removable partial dentures. Results:, Under bilateral and left side unilateral loading, the highest stress was observed adjacent to the left side posterior teeth with the polyacetal removable partial denture. The lowest stress was seen with the traditional metal framework. Unilateral loads on the right edentulous region produced similar distributed stress under the denture base with all three designs but a somewhat higher intensity with the polyacetal framework. Conclusions:, The polyacetal resin removable partial denture concentrated the highest stresses to the abutment and the bone. The traditional metal framework I-bar removable partial denture most equitably distributed force. The hybrid design that combined a metal framework and polyacetal clasp and denture base may be a viable alternative when aesthetics are of primary concern. [source] Bayesian nonparametric hierarchical modelingBIOMETRICAL JOURNAL, Issue 2 2009David B. Dunson Abstract In biomedical research, hierarchical models are very widely used to accommodate dependence in multivariate and longitudinal data and for borrowing of information across data from different sources. A primary concern in hierarchical modeling is sensitivity to parametric assumptions, such as linearity and normality of the random effects. Parametric assumptions on latent variable distributions can be challenging to check and are typically unwarranted, given available prior knowledge. This article reviews some recent developments in Bayesian nonparametric methods motivated by complex, multivariate and functional data collected in biomedical studies. The author provides a brief review of flexible parametric approaches relying on finite mixtures and latent class modeling. Dirichlet process mixture models are motivated by the need to generalize these approaches to avoid assuming a fixed finite number of classes. Focusing on an epidemiology application, the author illustrates the practical utility and potential of nonparametric Bayes methods. [source] Using Regression Models to Analyze Randomized Trials: Asymptotically Valid Hypothesis Tests Despite Incorrectly Specified ModelsBIOMETRICS, Issue 3 2009Michael Rosenblum Summary Regression models are often used to test for cause-effect relationships from data collected in randomized trials or experiments. This practice has deservedly come under heavy scrutiny, because commonly used models such as linear and logistic regression will often not capture the actual relationships between variables, and incorrectly specified models potentially lead to incorrect conclusions. In this article, we focus on hypothesis tests of whether the treatment given in a randomized trial has any effect on the mean of the primary outcome, within strata of baseline variables such as age, sex, and health status. Our primary concern is ensuring that such hypothesis tests have correct type I error for large samples. Our main result is that for a surprisingly large class of commonly used regression models, standard regression-based hypothesis tests (but using robust variance estimators) are guaranteed to have correct type I error for large samples, even when the models are incorrectly specified. To the best of our knowledge, this robustness of such model-based hypothesis tests to incorrectly specified models was previously unknown for Poisson regression models and for other commonly used models we consider. Our results have practical implications for understanding the reliability of commonly used, model-based tests for analyzing randomized trials. [source] Dealing with the board's first-order and second-order worries: Borrowing trouble effectivelyBOARD LEADERSHIP: POLICY GOVERNANCE IN ACTION, Issue 66 2003John CarverArticle first published online: 14 MAR 200 Planning is critical, but it is important that a board distinguish between planning to achieve ends and avoid unacceptable means and actually achieving ends and avoiding unacceptable means. Achievement is the primary concern of a Policy Governance board. However, if a board has credible concerns that management may not complete sufficient planning, it can be useful to create carefully crafted executive limitations policies on planning. [source] The Development of Symbol-Infused Joint EngagementCHILD DEVELOPMENT, Issue 4 2004Lauren B. Adamson Fifty-six children were observed longitudinally from 18 to 30 months of age interacting with their mothers during a Communication Play that contained 8 scenes designed to encourage interacting, requesting, commenting, and narrating. Of primary concern was how often symbols infused the child's states of engagement with people and objects and how experience in such symbol-infused states related to language acquisition. Findings indicate that symbols increasingly infuse joint engagement, and that both the timing and the trajectory vary widely among typically developing toddlers, especially during the last half of the 2nd year. Moreover, variations in amount of symbol-infused supported joint engagement may both be influenced by variations in the onset of language and contribute to differences in language facility at 30 months. [source] UNRAVELLING THE PATHOPHYSIOLOGY OF COMPLEX REGIONAL PAIN SYNDROME: FOCUS ON SYMPATHETICALLY MAINTAINED PAINCLINICAL AND EXPERIMENTAL PHARMACOLOGY AND PHYSIOLOGY, Issue 7 2008Gael F Gibbs SUMMARY 1In diseases such as complex regional pain syndrome (CRPS), where neuropathic pain is the primary concern, traditional pain classifications and lesion descriptors are of limited value. To obtain better treatment outcomes for patients, the underlying pathophysiological mechanisms of neuropathic pain need to be elucidated and analysed so that therapeutic targets can be identified and specific treatments developed. 2In the present review, we examine the current literature on sympathetically maintained pain (SMP), a subset of neuropathic pain, within the context of CRPS. Evidence from both human and animal studies is presented and discussed in terms of its support for the existence of SMP and the mechanistic information it provides. 3We discuss three current hypotheses that propose both a site and method for sympathetic,sensory coupling: (i) direct coupling between sympathetic and sensory neurons in the dorsal root ganglion; (ii) chemical coupling between sympathetic and nociceptive neuron terminals in skin; and (iii) the development of a-adrenoceptor-mediated supersensitivity in nociceptive fibres in skin in association with the release of inflammatory mediators. 4Finally, we propose a new hypothesis that integrates the mechanisms of chemical coupling and a-adrenoceptor-mediated supersensitivity. This hypothesis is based on previously unpublished data from our laboratory showing that a histological substrate suitable for sympathetic,sensory coupling exists in normal subjects. In the diseased state, the nociceptive fibres implicated in this substrate may be activated by both endogenous and exogenous noradrenaline. The mediating a-adrenoceptors may be expressed on the nociceptive fibres or on closely associated support cells. [source] Perils and Promise in Defining and Measuring Mindfulness: Observations From ExperienceCLINICAL PSYCHOLOGY: SCIENCE AND PRACTICE, Issue 3 2004Kirk Warren Brown As mindfulness research advances on a variety of fronts, it has become increasingly important to carefully define and measure the construct. In this commentary, we draw from our recent research experience on these topics in addressing four issues of primary concern to Bishop et al: The nature of mindfulness, the role of acceptance in the phenomenon, the relation between mindfulness and meditation, and the measurement of mindfulness in meditative and other contexts. [source] HDAC inhibitor valproic acid enhances tumor cell kill in adenovirus-HSVtk mediated suicide gene therapy in HNSCC xenograft mouse modelINTERNATIONAL JOURNAL OF CANCER, Issue 3 2010Vishal Kothari Abstract Safety, efficacy and enhanced transgene expression are the primary concerns while using any vector for gene therapy. One of the widely used vectors in clinical trials is adenovirus which provides a safe way to deliver the therapeutic gene. However, adenovirus has poor transduction efficiency in vivo since most tumor cells express low coxsackie and adenovirus receptors. Similarly transgene expression remains low, possibly because of the chromatization of adenoviral genome upon infection in eukaryotic cells, an effect mediated by histone deacetylases (HDACs). Using a recombinant adenovirus (Ad-HSVtk) carrying the herpes simplex thymidine kinase (HSVtk) and GFP genes we demonstrate that HDAC inhibitor valproic acid can bring about an increase in CAR expression on host cells and thereby enhanced Ad-HSVtk infectivity. It also resulted in an increase in transgene (HSVtk and GFP) expression. This, in turn, resulted in increased cell kill of HNSCC cells, following ganciclovir treatment in vitro as well as in vivo in a xenograft nude mouse model. [source] | |||||||||||||||||||||||||||||||||||||