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Sparse
Kinds of Sparse Terms modified by Sparse Selected AbstractsSub-Voxel Topology Control for Level-Set SurfacesCOMPUTER GRAPHICS FORUM, Issue 3 2003Stephan Bischoff Active contour models are an efficient, accurate, and robust tool for the segmentation of 2D and 3D image data. In particular, geometric deformable models (GDM) that represent an active contour as the level set of an implicitfunction have proven to be very effective. GDMs, however, do not provide any topology control, i.e. contours maymerge or split arbitrarily and hence change the genus of the reconstructed surface. This behavior is inadequate insettings like the segmentation of organic tissue or other objects whose genus is known beforehand. In this paperwe describe a novel method to overcome this limitation while still preserving the favorable properties of the GDMsetup. We achieve this by adding (sparse) topological information to the volume representation at locations whereit is necessary to locally resolve topological ambiguities. Since the sparse topology information is attached to theedges of the voxel grid, we can reconstruct the interfaces where the deformable surface touches itself at sub-voxelaccuracy. We also demonstrate the efficiency and robustness of our method. [source] Left Ventricular Non Compaction in ChildrenCONGENITAL HEART DISEASE, Issue 5 2010Sara H. Weisz MD ABSTRACT Left ventricular non compaction (LVNC) is a myocardial disease characterized by a hypertrabeculated myocardium. The hypertrabeculations in the left ventricular wall define deep recesses communicating with the left ventricular chamber where blood penetrates with increased risk of blood clots in the meshwork of the prominent trabeculations. The left ventricular apex and the free wall are particularly affected. During in utero ventriculogenesis, myocardial blood supply is initially linked to the presence of sinusoids, in which blood penetrates and diffuses nutriments and oxygen to myocardial cells. Progressively, with the development of the heart and the increase of cells demand of blood, coronary arteries system develops. This step is associated with myocardial modification that leads to compaction of hypertrabeculated myocardial net. Probably, the premature interruption of this process leads to ventricular noncompaction. Many studies have been conducted in adults with hypertrabeculated myocardium. To date, data regarding childhood LVNC are sparse. The aim of this review is to summarize the clinical and preclinical knowledge about LVNC in children. [source] Documenting Loss of Large Trophy Fish from the Florida Keys with Historical PhotographsCONSERVATION BIOLOGY, Issue 3 2009LOREN McCLENACHAN arrecifes de coral; ecología histórica; directrices cambiantes; peces de arrecife; sobrepesca Abstract:,A loss of large vertebrates has occurred in aquatic and terrestrial ecosystems, but data to measure long-term population changes are sparse. Historical photographs provide visual and quantitative evidence of changes in mean individual size and species composition for groups of marine fish that have been targeted by sport fishing. I measured such trends for 13 groups of recreationally caught "trophy" reef fish with photographs taken in Key West, Florida, from 1956 to 2007. The mean fish size declined from an estimated 19.9 kg (SE 1.5) to 2.3 kg (SE 0.3), and there was a major shift in species composition. Landings from 1956 to 1960 were dominated by large groupers (Epinephelus spp.), and other large predatory fish were commonly caught, including sharks with an average length of just <2 m. In contrast, landings in 2007 were composed of small snappers (Lutjanus spp. and Ocyurus chrysurus) with an average length of 34.4 cm (SE 0.62), and the average length of sharks declined by more than 50% over 50 years. Major declines in the size of fish caught were not reflected in the price of fishing trips, so customers paid the same amount for a less-valuable product. Historical photographs provide a window into a more pristine coral reef ecosystem that existed a half a century ago and lend support to current observations that unfished reef communities are able to support large numbers of large-bodied fish. Resumen:,Una pérdida de vertebrados mayores ha ocurrido en ecosistemas acuáticos y terrestres, pero los datos para medir los cambios poblaciones a largo plazo son escasos. Las fotografías históricas proporcionan evidencia visual y cuantitativa de cambios en el tamaño individual promedio y de la composición de especies en grupos de peces marinos que han sido blanco de la pesca deportiva. Medí esas tendencias en 13 grupos de peces de arrecife capturados recreativamente como "trofeos" mediante fotografías tomadas en Key West, Florida, desde 1956 a 2007. El peso promedio de los peces declinó de unos 19.9 kg (ES 1.5) a 2.3 kg (ES 0.3), y hubo un cambio mayor en la composición de especies. Las capturas entre 1956 y 1960 estuvieron dominadas por meros (Epinephelus spp.) grandes, y otros peces depredadores eran capturados comúnmente, incluyendo tiburones con una longitud promedio de poco menos de 2m. En contraste, las capturas en 2007 fueron compuestas de pargos (Lutjanus spp. y Ocyurus chrysurus) pequeños con una longitud promedio de 34.4 cm (ES 0.62), y la longitud promedio de los tiburones declinó más de 50% en 50 años. La gran declinación en el tamaño de los peces capturados no se reflejó en los precios de los viajes de pesca, así que los clientes pagaron la misma cantidad por un producto menos valioso. Las fotografías históricas proporcionan una visión de un ecosistema arrecifal coralino prístino que existió hace medio siglo y proporcionan soporte a los comentarios actuales de que las comunidades arrecifales no explotadas son capaces de soportar numerosos peces de talla grande. [source] Strategies for Successful Marine Conservation: Integrating Socioeconomic, Political, and Scientific FactorsCONSERVATION BIOLOGY, Issue 6 2005CAROLYN J. LUNDQUIST áreas marinas protegidas; planificación de conservación; reservas marinas Abstract:,As the process of marine-protected-area design and implementation evolves, the incorporation of new tools will advance our ability to create and maintain effective protected areas. We reviewed characteristics and approaches that contribute to successful global marine conservation efforts. One successful characteristic emphasized in most case studies is the importance of incorporating stakeholders at all phases of the process. Clearly defined goals and objectives at all stages of the design process are important for improved communication and standardized expectations of stakeholder groups. The inclusion of available science to guide the size and design of marine protected areas and to guide clear monitoring strategies that assess success at scientific, social, and economic levels is also an important tool in the process. Common shortcomings in marine conservation planning strategies include government instability and resultant limitations to monitoring and enforcement, particularly in developing nations. Transferring knowledge to local community members has also presented challenges in areas where in situ training, local capacity, and existing infrastructure are sparse. Inaccessible, unavailable, or outdated science is often a limitation to conservation projects in developed and developing nations. To develop and maintain successful marine protected areas, it is necessary to acknowledge that each case is unique, to apply tools and lessons learned from other marine protected areas, and to maintain flexibility to adjust to the individual circumstances of the case at hand. Resumen:,A medida que evoluciona el proceso de diseño e implementación de áreas marinas protegidas, la incorporación de nuevas herramientas mejorará nuestra habilidad para crear y mantener áreas protegidas efectivas. Revisamos las características y enfoques que contribuyen a los esfuerzos exitosos de conservación marina global. La importancia de incorporar a los actores en todas las fases del proceso es una característica exitosa enfatizada en la mayoría de los estudios de caso. Es importante que haya metas y objetivos claramente definidos para todas las etapas del proceso de diseño para mejorar la comunicación y estandarizar las expectativas de los grupos interesados. La inclusión de la ciencia disponible para guiar el tamaño y diseño de áreas marinas protegidas y para guiar las estrategias de monitoreo que evalúa el éxito a nivel científico, social y económico también son herramientas importantes en el proceso. Defectos comunes en las estrategias de planificación de conservación marina incluyen la inestabilidad gubernamental y las resultantes limitaciones para el monitoreo y vigilancia, particularmente en países en desarrollo. La transferencia de conocimiento a miembros de la comunidad local también ha enfrentado retos en áreas donde el entrenamiento in situ, la aptitud local y la infraestructura existente son escasos. La ciencia inaccesible, no disponible u obsoleta a menudo es una limitación para los proyectos de conservación en países desarrollados y en desarrollo. Para desarrollar y mantener áreas marinas protegidas exitosas, es necesario reconocer que cada caso es único, aplicar herramientas y lecciones aprendidas en otras áreas marinas protegidas y mantener la flexibilidad para ajustarse a las circunstancias individuales de cada caso. [source] Refining Biodiversity Conservation PrioritiesCONSERVATION BIOLOGY, Issue 6 2005GRANT M. HARRIS Bosque del Atlántico; percepción remota; priorización; SIG; sitios prioritarios para la conservación Abstract:,Although there is widespread agreement about conservation priorities at large scales (i.e., biodiversity hotspots), their boundaries remain too coarse for setting practical conservation goals. Refining hotspot conservation means identifying specific locations (individual habitat patches) of realistic size and scale for managers to protect and politicians to support. Because hotspots have lost most of their original habitat, species endemic to them rely on what remains. The issue now becomes identifying where this habitat is and these species are. We accomplished this by using straightforward remote sensing and GIS techniques, identifying specific locations in Brazil's Atlantic Forest hotspot important for bird conservation. Our method requires a regional map of current forest cover, so we explored six popular products for mapping and quantifying forest: MODIS continuous fields and a MODIS land cover (preclassified products), AVHRR, SPOT VGT, MODIS (satellite images), and a GeoCover Landsat thematic mapper mosaic (jpg). We compared subsets of these forest covers against a forest map based on a Landsat enhanced thematic mapper. The SPOT VGT forest cover predicted forest area and location well, so we combined it with elevation data to refine coarse distribution maps for forest endemic birds. Stacking these species distribution maps enabled identification of the subregion richest in threatened birds,the lowland forests of Rio de Janeiro State. We highlighted eight priority fragments, focusing on one with finer resolved imagery for detailed study. This method allows prioritization of areas for conservation from a region >1 million km2 to forest fragments of tens of square kilometers. To set priorities for biodiversity conservation, coarse biological information is sufficient. Hence, our method is attractive for tropical and biologically rich locations, where species location information is sparse. Resumen:,Aunque hay acuerdo generalizado sobre las prioridades de conservación a escalas mayores (i. e., sitios prioritarios para la conservación de la biodiversidad), los límites son muy gruesos como para definir metas de conservación prácticas. La refinación de la conservación de sitios prioritarios significa la identificación de localidades específicas (parches de hábitat individuales) de tamaño y escala realistas para ser protegidos por gestores y apoyados por políticos. Debido a que los sitios prioritarios han perdido la mayor parte de su hábitat original, las especies endémicas dependen del que permanece. Ahora el asunto es identificar donde están el hábitat y las especies. Logramos lo anterior mediante técnicas directas de percepción remota y de SIG para identificar localidades específicas importantes para la conservación de aves en el sitio prioritario Bosque del Atlántico en Brasil. Nuestro método requiere de un mapa regional de la cobertura forestal actual, así que exploramos seis productos populares para el mapeo y cuantificación de bosques: campos continuos MODIS y una cobertura de suelo MODIS (productos preclasificados), AVHRR, SPOT VGT, MODIS (imágenes de satélite) y un mosaico GeoCover Landsat thematic mapper (jpg). Comparamos subconjuntos de estas coberturas forestales con las de un mapa basado en un Landsat enhanced thematic mapper. La cobertura forestal SPOT VGT predijo bien la superficie y localización del bosque, así que lo combinamos con datos de altitud para refinar los mapas generales de distribución de aves endémicas de bosques. La sobreposición de estos mapas de distribución permitió la identificación de la subregión más rica en aves amenazadas,los bosques en bajíos del Estado de Río de Janeiro. Dimos relevancia a ocho fragmentos prioritarios, con atención en uno con imágenes de resolución fina para estudio en detalle. Este método permite la priorización de áreas para conservación de fragmentos de decenas de kilómetros cuadrados en una región >1 millón km2. La información biológica general es suficiente para definir prioridades de conservación de la biodiversidad. Por lo tanto, nuestro método es atractivo para localidades tropicales y biológicamente ricas, para las que la información sobre la ocalización de las especies es escasa. [source] Performance of Greater Sage-Grouse Models for Conservation Assessment in the Interior Columbia Basin, U.S.A.CONSERVATION BIOLOGY, Issue 5 2002Michael J. Wisdom Consequently, we evaluated the performance of two models designed to assess landscape conditions for Greater Sage-Grouse across 13.6 million ha of sagebrush steppe in the interior Columbia Basin and adjacent portions of the Great Basin of the western United States (referred to as the basin). The first model, the environmental index model, predicted conditions at the scale of the subwatershed (mean size of approximately 7800 ha) based on inputs of habitat density, habitat quality, and effects of human disturbance. Predictions ranged on a continuous scale from 0 for lowest environmental index to 2 for optimal environmental index. The second model, the population outcome model, predicted the composite, range-wide conditions for sage grouse based on the contribution of environmental index values from all subwatersheds and measures of range extent and connectivity. Population outcomes were expressed as five classes (A through E) that represented a gradient from continuous, well-distributed populations (outcome A) to sparse, highly isolated populations with a high likelihood of extirpation (outcome E). To evaluate performance, we predicted environmental index values and population outcome classes in areas currently occupied by sage grouse versus areas where extirpation has occurred. Our a priori expectations were that models should predict substantially worse environmental conditions ( lower environmental index) and a substantially higher probability of extirpation ( lower population outcome class) in extirpated areas. Results for both models met these expectations. For example, a population outcome of class E was predicted for extirpated areas, as opposed to class C for occupied areas. These results suggest that our models provided reliable landscape predictions for the conditions tested. This finding is important for conservation planning in the basin, where the models were used to evaluate management of federal lands for sage grouse. Resumen: Modelos válidos de hábitat y de poblaciones del urogallo (Centrocercus urophasianus) son una necesidad crítica para su manejo debido a la creciente preocupación por la viabilidad de la población. Por lo tanto, evaluamos el funcionamiento de dos modelos diseñados para evaluar las condiciones del paisaje para el urogallo en 13.6 millones de ha de la estepa de artemisa en la Cuenca Columbia Interior y las porciones adyacentes de la Gran Cuenca de los Estados Unidos occidentales (referidos como cuenca). El primer modelo (modelo de índice ambiental) predijo condiciones a escala de la subcuenca (tamaño promedio , 7800 ha) basado en información de la densidad del hábitat, calidad del hábitat y efectos de la perturbación humana. Las predicciones variaron en una escala continua a partir de 0 (el índice ambiental más bajo) a 2 (índice ambiental óptimo). El segundo modelo (modelo del resultado de la población) predijo las condiciones compuestas, de amplio rango, para el urogallo con base en la contribución de los valores de índice ambiental de todas las subcuencas y las medidas de extensión y de conectividad de la pradera. Los resultados de la población fueron expresados en cinco clases (A - E) que representan un gradiente de poblaciones continuas, bien-distribuidas (resultado A) a poblaciones escasas, altamente aisladas con una alta probabilidad de extirpación (resultado E). Para evaluar el funcionamiento, predijimos valores de índice ambiental y resultados de la población en las áreas actualmente ocupadas por urogallos versus áreas donde ha ocurrido la extirpación. Nuestras expectativas a priori eran que los modelos deben predecir condiciones ambientales substancialmente peores (índice ambiental más bajo) y una probabilidad de extirpación sustancialmente mayor (menor resultado de la población) en áreas extirpadas. Los resultados para ambos modelos cumplieron estas expectativas. Por ejemplo, se predijo un resultado de la población de la clase E para áreas extirpadas, en comparación con la clase C para áreas ocupadas. Estos resultados sugieren que nuestros modelos proporcionaron predicciones de paisaje confiables para las condiciones probadas. Este hallazgo es importante para planeación de la conservación de la cuenca, donde los modelos fueron utilizados para evaluar el manejo de terrenos federales para urogallos. [source] Sesquiterpene lactone dermatitis in the young: is atopy a risk factor?CONTACT DERMATITIS, Issue 1 2008Evy Paulsen Screening for Compositae contact allergy has documented fairly high prevalence in adults, and recent studies indicate that the allergy may be more common in children than previously believed. However, detailed information on sensitization in this age group is sparse. The objective of this study was to present another 2 cases in children and review the literature. Screening with sesquiterpene lactone (SL) mix has shown prevalence of 0.5% and 1.8% in 2 studies, while screening with 2 different Compositae mixes detected 4.2% and 2.6% positives among children and adolescents. All individual case reports describe sensitization in atopic children, and the largest screening study showed a prevalence of Compositae mix sensitization that was significantly higher in children with atopic dermatitis compared with non-atopics. Compositae sensitization should be considered in children with a family or personal history of atopy, summer-related, or -exacerbated dermatitis of any kind, and a history of plant exposure. Screening with SL mix is recommended but should be supplemented with plant extracts based on exposure history. Compositae weeds, especially dandelions, seem to be important sensitizers in children. [source] Board Structure, Process and Performance: evidence from public-listed companies in SingaporeCORPORATE GOVERNANCE, Issue 2 2005David Wan Past literature in board research has centred on board structure and company performance. Over the years, empirical studies do not reveal a conclusive relationship between these two variables (Dalton and Daily, 1999. Across the Board, March, 28,32). Until recently, the literature on board processes has been sparse. The reason for insufficient empirical work on board processes possibly is due to the difficulty of gaining access to boards. In this paper, we propose a conceptual model and tested the model on publicly listed companies in Singapore. Based on a sample of 212 company responses and 299 directors, we conclude that board structure does not affect board process while board process is related to board performance. In terms of individual parameters, effort norms, cognitive conflict and the presence and usage of skills are positively related to board roles and board transparency. Also, affective and process conflicts are negatively related to board roles and board transparency. Finally, board process does not mediate the relationship between board structure and board performance. [source] Learning from New Product Development Projects: An Exploratory StudyCREATIVITY AND INNOVATION MANAGEMENT, Issue 4 2005Ursula Koners Knowledge generation is a cornerstone of new product development, and post-project reviews (PPRs) are widely recognized as a facilitator of project-to-project learning. Empirical research on PPRs is sparse, so this paper describes four in-depth exploratory case studies that look at how PPRs are conducted and the learning that can result. The results indicate that appropriately managed PPRs can make a significant contribution to knowledge generation and exchange. In addition, the study indicates the urgent need for more research into this important area. [source] Calcium handling in afferent arteriolesACTA PHYSIOLOGICA, Issue 4 2004M. Salomonsson Abstract The cytosolic intracellular calcium concentration ([Ca2+]i) is a major determining factor in the vascular smooth muscle tone. In the afferent arteriole it has been shown that agonists utilizing G-protein coupled receptors recruit Ca2+ via release from intracellular stores and entry via pathways in the plasma membrane. The relative importances of entry vs. mobilization seem to differ between different agonists, species and preparations. The entry pathway might include different types of voltage sensitive Ca2+ channels located in the plasmalemma such as dihydropyridine sensitive L-type channels, T-type channels and P/Q channels. A role for non-voltage sensitive entry pathways has also been suggested. The importance of voltage sensitive Ca2+ channels in the control of the tone of the afferent arteriole (and thus in the control of renal function and whole body control of extracellular fluid volume and blood pressure) sheds light on the control of the membrane potential of afferent arteriolar smooth muscle cells. Thus, K+ and Cl, channels are of importance in their role as major determinants of membrane potential. Some studies suggest a role for calcium-activated chloride (ClCa) channels in the renal vasoconstriction elicited by agonists. Other investigators have found evidence for several types of K+ channels in the regulation of the afferent arteriolar tone. The available literature in this field regarding afferent arterioles is, however, relatively sparse and not conclusive. This review is an attempt to summarize the results obtained by others and ourselves in the field of agonist induced afferent arteriolar Ca2+ recruitment, with special emphasis on the control of voltage sensitive Ca2+ entry. Outline of the Manuscript: This manuscript is structured as follows: it begins with an introduction where the general role for [Ca2+]i as a key factor in the regulation of the tone of vascular smooth muscles (VSMC) is detailed. In this section there is an emphasis is on observations that could be attributed to afferent arteriolar function. We then investigate the literature and describe our results regarding the relative roles for Ca2+ entry and intracellular release in afferent arterioles in response to vasoactive agents, with the focus on noradrenalin (NA) and angiotensin II (Ang II). Finally, we examine the role of ion channels (i.e. K+ and Cl, channels) for the membrane potential, and thus activation of voltage sensitive Ca2+ channels. [source] Panic disorder phenomenology in urban self-identified caucasian,non-hispanics and caucasian,hispanicsDEPRESSION AND ANXIETY, Issue 1 2003Michael Hollifield M.D. Abstract The epidemiology of panic disorder is well known, but data about some phenomenological aspects are sparse. The symptom criteria for panic disorder were developed largely from rational expert consensus methods and not from empirical research. This fact calls attention to the construct validity of the panic disorder diagnosis, which may affect accuracy of epidemiological findings. Seventy self-identified Non-Hispanic,Caucasian (Anglo) and Hispanic,Caucasian (Hispanic) people who were diagnosed with DSM-III-R panic disorder with or without agoraphobia were invited to complete a Panic Phenomenological Questionnaire (PPQ), which was constructed for this study from the Hamilton Anxiety Scale Items and The DSM-III-R panic symptoms. Fifty (71%) subjects agreed to participate, and there was no response bias detected. Seven symptoms on the PPQ that are not in the DSM-IV diagnostic criteria were reported to occur with a high prevalence in this study. Furthermore, many symptoms that occurred with a high frequency and were reported to be experienced as severe are also not included in current nosology. A few of the DSM-IV criterion symptoms occurred with low prevalence, frequency, and severity. Cognitive symptoms were reported to occur with higher frequency and severity during attacks than autonomic or other symptoms. There were modest differences between ethnic groups with regard to panic attack phenomena. Further research using multiple empirical methods aimed at improving the content validity of the panic disorder diagnosis is warranted. This includes utilizing consistent methods to collect data that will allow for rational decisions about how to construct valid panic disorder criteria across cultures. Depression and Anxiety 18:7,17, 2003. © 2003 Wiley-Liss, Inc. [source] Assessment of executive function in preschool-aged childrenDEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 3 2005Peter K. Isquith Abstract Assessment of the overarching self-regulatory mechanisms, or executive functions, in any age group is challenging, in part due to the complexity of this domain, in part due to their dynamic essence, and in part due to the inextricable links between these central processes and the associated domain-specific processes, such as language, motor function, and attention, over which they preside. While much progress has been made in clinical assessment approaches for measuring executive functions in adults and to some extent in adolescents and school-aged children, the toolkit for the preschool evaluator remains sparse. The past decade, however, has seen a substantial increase in attention to executive functions in very young children from a developmental neuropsychological perspective. With this has come a necessity for better, more specific, and more internally valid performance measures, many of which are now described in the experimental literature. Few such tasks, however, have adequately demonstrated psychometric properties for clinical application. We present two performance tasks designed to tap selective aspects of executive function in preschoolers that are emerging from the experimental laboratory and hold promise of appropriate reliability and validity for the clinical laboratory. Performance tests alone, however, are insufficient to develop a comprehensive picture of a child's executive functioning. Thus, we present a rating scale of preschoolers' executive function in the everyday context, and advocate a model of executive function assessment that incorporates both controlled performance tasks that target specific aspects of executive function and parent/teacher ratings that target more global aspects of self-regulation in the everyday context. © 2005 Wiley-Liss, Inc. MRDD Research Reviews 2005;11:209,215. [source] Mechanical computation in neuronsDEVELOPMENTAL NEUROBIOLOGY, Issue 11 2009Jummi Laishram Abstract Growth cones are the main motile structures located at the tip of neurites and are composed of a lamellipodium from which thin filopodia emerge. In this article, we analyzed the kinetics and dynamics of growth cones with the aim to understand two major issues: first, the strategy used by filopodia and lamellipodia during their exploration and navigation; second, what kind of mechanical problems neurons need to solve during their operation. In the developing nervous system and in the adult brain, neurons constantly need to solve mechanical problems. Growth cones must decide how to explore the environment and in which direction to grow; they also need to establish the appropriate contacts, to avoid obstacles and to determine how much force to exert. Here, we show that in sparse cultures, filopodia grow and retract following statistical patterns, nearly optimal for an efficient exploration of the environment. In a dense culture, filopodia exploration is still present although significantly reduced. Analysis on 1271, 6432, and 185 pairs of filopodia of DRG, PC12 and Hippocampal neurons respectively showed that the correlation coefficient |,| of the growth of more than 50% of filopodia pairs was >0.15. From a computational point of view, filopodia and lamellipodia motion can be described by a random process in which errors are corrected by efficient feedback loops. This article argues that neurons not only process sensory signals, but also solve mechanical problems throughout their entire lifespan, from the early stages of embryogenesis to adulthood. © 2009 Wiley Periodicals, Inc. Develop Neurobiol, 2009 [source] Does antipsychotic withdrawal provoke psychosis?ACTA PSYCHIATRICA SCANDINAVICA, Issue 1 2006Review of the literature on rapid onset psychosis (supersensitivity psychosis), withdrawal-related relapse Objective:, To examine the evidence that discontinuation of long-term antipsychotic medication, including clozapine, may provoke a psychotic episode. Method:, Databases were searched and citations scrutinised. Results:, Evidence for a rapid onset psychosis (supersensitivity psychosis) following clozapine withdrawal was found and weaker evidence that this might occur with some other antipsychotic drugs. Some cases were reported in people without a psychiatric history. It appears that the psychosis may be a feature of drug withdrawal rather than the re-emergence of an underlying illness, at least in some patients. Meta-analyses of withdrawal studies have suggested that antipsychotic discontinuation may also increase the risk of relapse over and above the risk because of the underlying disorder, but not all individual studies show this effect. Mechanisms may relate to brain adaptations to long-term drug use but data are sparse. Conclusion:, These effects require further urgent research. Interventions to reduce morbidity after drug withdrawal need to be developed. [source] Managing childhood obesity: when lifestyle change is not enoughDIABETES OBESITY & METABOLISM, Issue 11 2010C. Hearnshaw The management of childhood obesity is a clinical dilemma. Paediatricians will see those children whose weight is at the severe end of the spectrum with obesity-related co-morbidities and for whom more intensive weight loss therapies may be appropriate. A literature review was performed (January 1995,January 2010) of the roles of pharmacotherapy or bariatric surgery in the management of childhood obesity. Three hundred and eighty-three abstracts were reviewed and 76 full-text articles were requested. Of these, 34 were excluded and a total of 21 pharmacotherapy papers and 22 papers on surgery were reviewed in detail. All studies involved adolescents. Pharmacotherapy: Most studies were small and of short duration, the notable exceptions being two large RCTs of sibutramine and orlistat. Sibutramine led to a mean estimated change in BMI from baseline of ,3.1 kg/m2 vs. ,0.3 kg/m2 for placebo over 12 months. Orlistat was also beneficial with a mean reduction in BMI of 0.55 vs. an increase of 0.31 kg/m2 in the placebo group at 12 months. Bariatric surgery: Most papers presented clinical observations and there were no randomised controlled trials (RCTs). Robust selection criteria were not used and ideal candidate selection remains unclear. Most papers showed a significant benefit of surgery in severely obese adolescents in the short term but long-term data were sparse. There were a surprisingly large number of papers examining the benefits of intensive weight management in obese adolescents. The study design of many was inadequate and the role of pharmacotherapy or surgery in childhood obesity remains unclear. [source] The effects of applied felted foam on wound healing and healing times in the therapy of neuropathic diabetic foot ulcersDIABETIC MEDICINE, Issue 8 2003S. Zimny Abstract Aims The application of felted foam is a promising method for plantar pressure reduction in the ulcer region of diabetic foot ulcers, but knowledge of its effects on wound healing is sparse. The objective of this study was to evaluate the effects of felted foam on wound healing in diabetic foot ulcers compared with a standard method of plantar pressure relief. Materials and methods A total of 54 Type 1 or Type 2 diabetic patients with neuropathic diabetic foot ulcers were evaluated in this prospective randomized controlled study. Ulcer healing was assessed by planimetric measurement of the wound area at beginning of the study and after 10 weeks and at least until wound healing. The patients were consecutively enrolled in the study; 24 patients were randomized to the felted foam therapy, and 30 patients were randomized to conventional therapy. Results In the felted foam group, the initial average wound area was 102.3 ± 45.3 mm2 (mean ± sd), and 5.4 ± 3.1 mm2 after 10 weeks with an average healing time of 75 days [95% confidence interval (CI) 67,84]. In the conventional therapy group, the initial average wound area was 112.5 ± 50.8 mm2, and 10.6 ± 4.2 mm2 after 10 weeks with an average healing time of 85 days (95% CI 79,92) (P = 0.03). The mean wound radius decreased by 0.48 mm (95% CI 0.42,0.56) per week in the felted foam group and by 0.39 mm (95% CI 0.35,0.42) per week in the conventional group (P = 0.005). Conclusions The felted foam technique appears to be at least as effective as conventional plantar ulcer treatment. It may be a useful alternative in treating neuropathic foot ulceration, especially in patients who are not able to avoid weight-bearing reliably. [source] Estrogen and progesterone receptors in esophageal carcinomaDISEASES OF THE ESOPHAGUS, Issue 4 2008R. Kalayarasan SUMMARY., Information is sparse and contradictory in the literature regarding the role of estrogen receptor (ER) and progesterone receptor (PR) in esophageal carcinoma. This study was conducted over a period of 18 months from September 2004 with the primary aim of determining the PR, ER alpha (ER,) and ER beta (ER,) status of esophageal carcinoma and normal esophageal mucosa (NEM). The receptor status was correlated with tumor type, tumor differentiation and tumor stage. A total of 45 patients with histologically proven squamous cell carcinoma (SCC) (n = 30) and adenocarcinoma (AC) (n = 15) were studied. Receptor status was detected by immunohistochemistry (IHC) and semiquantitative assessment was done by quick score method of endoscopic biopsy specimens. The mean age for SCC and AC were not significantly different. The gender ratio in favor of males was 3 : 2 for SCC and 4 : 1 for AC. None of the specimens from SCC or AC showed positivity for PR both in NEM and tumor tissue. Likewise none of the specimens were positive for ER, by IHC. The mean ER, score for AC was significantly higher than SCC. For SCC it was seen that ER, positivity in tumor cells increases with dedifferentiation and increasing tumor stage. This trend was seen for AC as well. ER, is over-expressed in poorly differentiated SCC and AC compared to NEM. Thus ER, may be a marker for poor biological behavior, that is dedifferentiation or higher stage of disease. In view of these findings we propose a large-scale prospective, longitudinal interventional study using selective estrogen modulators. [source] Morphological variation of the five vole species of the genus Microtus (Mammalia, Rodentia, Arvicolinae) occurring in GreeceACTA ZOOLOGICA, Issue 3 2009Stella E. Fraguedakis-Tsolis Abstract Morphometric data for the five vole species of the genus Microtus living in Greece are old, sparse, poor and insufficiently analysed. This work aims to give the first comprehensive morphometric analysis of body and skull inter- and intraspecific variation for M. (M.) guentheri, M. (M.) rossiaemeridionalis, M. (Terricola) subterraneus, M. (T.) felteni and M. (T.) thomasi, applying multivariate statistics to 28 linear morphometric variables. It was based on ample material (202 adult individuals) using samples from localities that adequately cover the entire distributional range of each species in Greece. The five species and the two subgenera (Microtus and Terricola) were morphometrically clearly distinguished and discriminating variables were revealed. However, morphometrics did not provide robust criteria to infer phylogenetic relations among species. Furthermore, three species, M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi, exhibited considerable intraspecific size or shape variation, which was mostly random and not associated with geographical proximity. Comparisons with data in the literature, mainly concerning populations of these species from adjacent areas, indicate that the Greek M. (M.) guentheri, M. (M.) rossiaemeridionalis and M. (T.) thomasi tend to be smaller than their conspecifics, while M. (T.) subterraneus and M. (T.) felteni are about equal in size to their Balkan relatives. [source] A geomatics data integration technique for coastal change monitoringEARTH SURFACE PROCESSES AND LANDFORMS, Issue 6 2005J. P. Mills Abstract This paper reports research carried out to develop a novel method of monitoring coastal change, using an approach based on digital elevation models (DEMs). In recent years change monitoring has become an increasingly important issue, particularly for landforms and areas that are potentially hazardous to human life and assets. The coastal zone is currently a sensitive policy area for those involved with its management, as phenomena such as erosion and landslides affect the stability of both the natural and the built environment. With legal and financial implications of failing to predict and react to such geomorphological change, the provision of accurate and effective monitoring is essential. Long coastlines and dynamic processes make the application of traditional surveying difficult, but recent advances made in the geomatics discipline allow for more effective methodologies to be investigated. A solution is presented, based on two component technologies , the Global Positioning System (GPS) and digital small format aerial photogrammetry , using data fusion to elim-inate the disadvantages associated with each technique individually. A sparse but highly accurate DEM, created using kinematic GPS, was used as control to orientate surfaces derived from the relative orientation stage of photogrammetric processing. A least squares surface matching algorithm was developed to perform the orientation, reducing the need for costly and inefficient ground control point survey. Change detection was then carried out between temporal data epochs for a rapidly eroding coastline (Filey Bay, North Yorkshire). The surface matching algorithm was employed to register the datasets and determine dif-ferences between the DEM series. Large areas of change were identified during the lifetime of the study. Results of this methodology were encouraging, the flexibility, redundancy and automation potential allowing an efficient approach to landform monitoring. Copyright © 2005 John Wiley & Sons, Ltd. [source] Colonisation of pitcher plant leaves at several spatial scalesECOLOGICAL ENTOMOLOGY, Issue 4 2003M. Kurtis Trzcinski Abstract., 1.,The effect of meso-scale (zone within bog and local plant density) and fine-scale (leaf length and resource availability) factors on the colonisation of pitcher plant leaves by arthropods was examined in an eastern Canadian bog. 2.,In spring, the abundances of three arthropods, the mosquito Wyeomyia smithii, the midge Metriocnemus knabi, and the mite Sarraceniopus gibsoni, were determined for plots with low, moderate, and high densities of pitcher plants. All overwintering inhabitants were then removed from the plots. Newly opening leaves were colonised from outside the plots, and arthropod abundances were assessed again in autumn. 3.,Pitcher plant fauna varied in their response to the meso-scale factors. In autumn (soon after colonisation), midges were more abundant in areas with high densities of pitcher plants. The relationship between mosquito abundance and plant density, and the variation in abundance among zones within the bog in the spring, were probably due to overwintering mortality. 4.,All taxa responded to the fine-scale factors, leaf length, and capture rate, in the autumn, but the strength of the responses frequently depended on a meso-scale factor (plant density), in which responses were usually strongest where plants were sparse. Thus, the interaction between meso- and fine-scale processes needs to be considered when interpreting patterns of species abundance within arthropod assemblages in pitcher plant leaves. [source] How does the periapical inflammatory process compromise general health?ENDODONTIC TOPICS, Issue 1 2004Idikó. Several lines of evidence support the causative role of oral inflammatory lesions and certain systemic diseases, such as atherosclerosis and cardiovascular diseases, adverse pregnancy outcome and lung diseases. Properly executed epidemiologic studies identified increased odds ratios. Local or metastatic spread of oral microorganisms, local production of microbial or host-derived soluble regulatory molecules, that may initiate or sustain inflammatory events in remote tissues and organs and the presence of (a) common , extrinsic- or intrinsic-pathological mechanism(s) may result in or contribute to both local and systemic inflammation. A number of cross-sectional studies addressing a possible association between oral health and systemic diseases have also investigated the presence or the absence of periapical lesions. However, these studies cannot either confirm or refute a role of the periapical inflammatory lesion in the observed associations, since other variables of oral health might have exerted an inestimable influence on general health of the assessed population. The literature, dealing with patients with root canal infections and apical periodontitis as sole oral inflammatory lesions is extremely sparse. Our group has demonstrated that young adults with apical periodontitis exhibit certain biochemical changes, such as elevated levels of C-reactive protein and an increased whole blood chemiluminescence, which have been shown to elevate the risk for cardiovascular diseases. Future research will be required to determine whether and to what extent may endodontic diseases affect general health. [source] The effect of travel time on oviposition behavior and spatial egg aggregation: experiments with DrosophilaENTOMOLOGIA EXPERIMENTALIS ET APPLICATA, Issue 3 2007Kazuo H. Takahashi Abstract A higher degree of spatial egg aggregation is often observed in environments where resource patches are more sparsely distributed. This suggests a higher probability of species coexistence when resource distribution is sparse. However, it is still unclear how the degree of spatial egg aggregation increases. I propose a model to explain this phenomenon, which assumes that (i) egg load (the number of mature eggs in ovaries) increases in the travel period between resource patches and (ii) the retention of eggs in the ovaries is harmful (egg load pressure). With these assumptions, a female would lay accumulated eggs on arrival at a new resource patch, resulting in a higher degree of spatial egg aggregation. Laboratory experiments with three drosophilid species, Drosophila simulans Surtevant, Drosophila auraria Peng, and Drosophila immigrans Sturtevant, support the model. This study provides evidence that host availability affects the spatial egg aggregation via egg load. [source] Destiny matters: distal developmental influences on adult alcohol use and abuseADDICTION, Issue 2008John E. Schulenberg ABSTRACT A foundational assumption in the fields of addiction and developmental psychopathology is that child and adolescent experiences set the stage for adult functioning and adjustment. However, the empirical literature documenting life-span linkages with adult alcohol (and other drug) use and abuse is sparse. This gap is due to a slow adoption of life-span developmental conceptualizations and the lack of long-term prospective longitudinal studies. This supplemental issue provides evidence for such linkages from six long-term longitudinal studies, which together follow individuals from birth through to the late 40s. The data sets include national and regional samples from Britain, Finland and the United States. In this introductory paper, we consider conceptual issues concerning linkages across the life-span culminating in adult alcohol use and disorders, and provide a summary of the purposes and common themes. [source] Quality-of-Life and Behavioral Outcome Measures in Randomized Controlled Trials of Antiepileptic Drugs: A Systematic Review of Methodology and Reporting StandardsEPILEPSIA, Issue 11 2000Gus A. Baker Summary: Purpose: To review the methodology and use of quality-of-life and behavioral measures used in randomized controlled trials (RCTs) of antiepileptic drugs in patients with epilepsy. Methods: Trial reports were found by searching a previously developed comprehensive database of epilepsy RCTs and searching through journals by hand. Inclusion and exclusion criteria were applied, and methodological and quality-of-life and behavioral measure data were extracted. Results: There were 52 different measures used in 46 trials, with the Profile of Mood States, the Minnesota Multiphasic Personality Inventory, and the Washington Psychosocial Seizure Inventory being applied the most frequently. Overall, evidence of the reliability, validity, and sensitivity of measures used in populations of people with epilepsy was sparse. There was also little information on the clinical interpretation of the results. Conclusion: Our results highlight a consistent failure to apply quality-of-life and behavioral measures in RCTs in a systematic way. We found repeated evidence of researchers' failure to review the use of previous measures and selection of measures without evidence of their appropriateness for use in a population with epilepsy. We recommend the use of quality-of-life and behavioral measures in RCTs with proven psychometric properties in a population with epilepsy. [source] Two clinical manifestations of desmopathy of the accessory ligament of the deep digital flexor tendon in the hindlimb of 23 horsesEQUINE VETERINARY JOURNAL, Issue 6 2005E. ELIASHAR Summary Reasons for performing study: Desmopathy of the accessory ligament of the deep digital flexor tendon (ALDDFT) in the hindlimb is an unusual cause of lameness in horses, and reports of the condition are sparse. Objectives: To describe the clinical and ultrasonographic findings, therapy and outcome of 23 horses treated for desmopathy of the ALDDFT in the hindlimb. Methods: Records of 23 horses with ultrasonographic evidence of desmopathy of the ALDDFT in one or both hindlimbs from 3 referral centres were reviewed retrospectively. Age, breed, sex, duration and nature of clinical signs, results of clinical and lameness examinations, treatment and outcome were recorded. Results: In 13 horses (Group A), there was an acute onset of unilateral lameness. Ten horses (Group B) had an insidious or sudden onset of postural abnormality. There were 10 cobs, 5 British native-breed ponies and 8 horses of various larger breeds. Twenty horses were used for general purposes, and mean age was 12 years. Enlargement of the ALDDFT in the affected hindlimb(s) was identified in all horses. In 44% of horses, ultrasonographic abnormalities were localised to part of the ALDDFT. Treatment included box-rest and controlled exercise, and 10 horses were subjected to desmotomy or desmectomy of the ALDDFT. Seventy-three percent of horses in Group A returned to full function, while 90% of those in Group B remained lame. Conclusions: Two distinct clinical conditions are associated with the ALDDFT of the hindlimb. Traumatically induced injury resulting in acute onset lameness appears to have a favourable prognosis, with most horses returning to previous work. However, postural changes, once present, are irreversible and indicate a poor prognosis. Potential relevance: Desmopathy of the ALDDFT should be recognised as a potential cause of hindlimb lameness and this study provides clinical and prognostic information. Knuckling and/or semiflexion of the metatarsophalangeal joint may accompany the condition; therefore, if a horse is presented with a flexural deformity of this joint, desmopathy of the ALDDFT should be considered as a primary differential diagnosis. [source] Night time eating: a review of the literatureEUROPEAN EATING DISORDERS REVIEW, Issue 1 2003Martina de Zwaan Abstract This study reviews the published research on night time eating, including the night eating syndrome (NES) and the nocturnal eating/drinking syndrome (NEDS). Studies were identified by a computerized literature search (PubMed, PsycInfo) and by references from the papers obtained. In addition, published abstracts from recent conferences in the areas of eating disorders and obesity were included. Individual studies were reviewed and their results summarized. Wakeful night time eating appears to be a frequent symptom which is more common among the obese. The data suggest an early age of onset with a chronic course in many patients. There appears to be considerable overlap between NES and NEDS. Treatment studies are sparse. The clinical features of these syndromes, their comorbidities, and their prevalence rates remain a matter of debate. It is unclear if the night eating syndrome presents a distinct entity that is of clinical relevance. The current nosologies may not capture the natural clustering of eating and sleep-related pathology as it occurs in general population samples. Copyright © 2003 John Wiley & Sons, Ltd and Eating Disorders Association. [source] Eating disorders in females with type 1 diabetes: an update of a meta-analysisEUROPEAN EATING DISORDERS REVIEW, Issue 4 2002Søren Nielsen Abstract Objective: Firstly to provide a quantitative summary of existing studies on the occurrence of eating disorders (ED) in females with type 1 diabetes (IDDM), with the focus on retinopathy and insulin misuse for the different eating disorders. Secondly to disseminate knowledge about useful statistical tools. Research Design and Methods: Data were extracted from the relevant case,control and follow-up studies. Odds ratios (OR) and risk differences (RD) were the main effect sizes analysed. Analyses were based on ,exact' methods as many studies are sparse. Data and findings are presented in sufficient detail for re-analysis. Results: An hypothesis of an increase in Anorexia Nervosa (AN) in IDDM is not supported by existing evidence. Bulimia Nervosa is increased (OR,=,2.9 (95%CI: 1.03 to 8.4); pOR,=,0.04) in IDDM. Both ED-NOS and subthreshold ED is increased (OR ,2; pOR,<,0.001) in females with IDDM. Co-existing ED in IDDM increases the overall common OR for retinopathy to 4.8 (95%CI: 3.0 to 7.8); pOR,<,0.00001, and the overall mean RD is 33% (95%CI: 25% to 42%); pRD,<,0.001. Insulin misuse (IM) is increased when ED co-exists with IDDM: OR 12.6 (95%CI: 7.8 to 21.1); pOR,<,0.00001, and mean RD is 40% (95%CI: 29% to 50%); pRD,<,0.001. Conclusions: ED-NOS and subthreshold ED seem to be the quantitatively most important EDs in type 1 diabetic females. Mismanagement of diabetes in the form of IM is frequent in eating disordered IDDM probands. Early occurrence of retinopathy and other complications is an increased risk in concurrent cases, as is premature death. The implications of Binge Eating Disorder (BED) and overweight needs to be elucidated for both type 1 and type 2 diabetes. Copyright © 2002 John Wiley & Sons, Ltd and Eating Disorders Association. [source] The use of brief interventions adapted from motivational interviewing across behavioral domains: a systematic reviewADDICTION, Issue 12 2001Chris Dunn Aims. To examine the effectiveness of brief behavioral interventions adapting the principles and techniques of Motivational Interviewing (MI) to four behavioral domains: substance abuse, smoking, HIV risk and diet/exercise. Design. We conducted a systematic review of 29 randomized trials of MI interventions. Data on methodological quality were extracted and tabulated. Between-group behavior change effect sizes and confidence intervals were calculated for each study. Findings. Due to varying intervention time lengths, targeted problem behaviors, settings and interventionists' backgrounds and skill levels, outcomes were not combined meta-analytically. Sixty per cent of the 29 studies yielded at least one significant behavior change effect size. No significant association between length of follow-up time and magnitude of effect sizes was found across studies. There was substantial evidence that MI is an effective substance abuse intervention method when used by clinicians who are non-specialists in substance abuse treatment, particularly when enhancing entry to and engagement in more intensive substance abuse treatment treatment-as-usual. Data were inadequate to judge the effect of MI in the other domains. Client attribute-treatment interactions were understudied and the sparse and inconsistent findings revealed little about the mechanism by which MI works or for whom it works best. Conclusion. To determine more effectively how well MI works in domains other than substance abuse and for whom it works best in all domains, researchers should study MI with risk behaviors other than substance abuse, while examining both interactions and the theoretical components of MI. [source] A case of hepatosplenic ,,, T-cell lymphoma with a transient response to Fludarabine and AlemtuzumabEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 6 2006S. Mittal Abstract:, Hepatosplenic ,,, T-cell lymphoma is a rare, usually fatal lymphoma and available literature on management is sparse. Allografting is probably the only curative option. We describe a further case with a dramatic, though transient response to Fludarabine and Alemtuzumab combination, following a failure of conventional chemotherapy. Given the dreadful prognosis with conventional chemotherapy, it is a regimen worth pursuing as a disease reduction strategy prior to allograft where appropriate. [source] Constitutive expression of the FK506 binding protein 51 (FKBP51) in bone marrow cells and megakaryocytes derived from idiopathic myelofibrosis and non-neoplastic haematopoiesisEUROPEAN JOURNAL OF HAEMATOLOGY, Issue 4 2004Oliver Bock Abstract: Objectives:, Overexpression of FK506 binding protein 51 (FKBP51) in megakaryocytic progenitor cells generated from purified CD34+ cells in patients with idiopathic myelofibrosis (IMF) has been demonstrated. It has been suggested that FKBP51 is involved in the dysregulation of the apoptotic programme with consecutive prolongation of cell survival. The knowledge of FKBP51 and its expression in bone marrow cells and mature megakaryocytes in non-neoplastic haematopoiesis and IMF is sparse. Methods:, To evaluate a potential overexpression of FKBP51 in patients with IMF (n = 37) compared with non-neoplastic haematopoiesis (n = 31), total bone marrow cells as well as single megakaryocytes, isolated by laser microdissection, were quantitatively analysed by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). By applying immunohistochemistry, FKBP51 gene expression was correlated with staining pattern and cellular localisation of the corresponding FKBP51 protein. Results:, We demonstrated that FKBP51 is constitutively expressed in non-neoplastic haematopoiesis. FKBP51 gene expression by total bone marrow cells as well as megakaryocytes was not significantly different in IMF. FKBP51 protein expression could be localised to myeloid progenitor cells as well as megakaryocytes. In particular, megakaryocytes were stained almost exclusively nuclear for FKBP51. No differences in expression patterns between both IMF and control cases could be demonstrated. Conclusions:, For the first time, FKBP51 expression, in particular gene expression and subcellular localization was described in bone marrow cells of non-neoplastic and neoplastic haematopoiesis grown in vivo. We conclude that FKBP51 could be temporarily overexpressed in megakaryocytic progenitors rather than contribute to the accumulation of mature megakaryocytes in IMF. [source] | ||||||||||||||||||||||||||||||||||||||||||||||||||||