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Selected AbstractsMembranen für Polymerelektrolyt-Brennstoffzellen,CHEMIE-INGENIEUR-TECHNIK (CIT), Issue 11 2003A. Glüsen Dr. rer. nat. Abstract Die Polymerelektrolyt-Membran ist das Herzstück von wasserstoffbetriebenen Polymerelektrolyt-Brennstoffzellen (PEFC) und methanolbetriebenen Direktmethanol-Brennstoffzellen (DMFC). Membranen aus sulfonierten Fluoropolymeren sind derzeit kommerziell erhältlich. Wichtige Forschungs- und Entwicklungsziele sind derzeit für die PEFC die Erhöhung der Betriebstemperatur, ohne die Membran zusätzlich befeuchten zu müssen, und für die DMFC die Verringerung des Methanoltransportes durch die Membran. Zusätzlich sollen durch die Verwendung fluorfreier Polymere die Kosten der Membran und die Umweltbelastung reduziert werden. Dabei spielen bereits in der industriellen Entwicklung befindliche Membranen ebenso eine Rolle wie neue Membrankonzepte aus der Grundlagenforschung. Membranes for Polymer Electrolyte Fuel Cells The polymer electrolyte membrane is the heart of hydrogen fuelled Polymer Electrolyte Fuel Cells (PEFC) and methanol fuelled Direct Methanol Fuel Cells (DMFC). Membranes of sulfonated fluoropolymers are already commercially available. Important goals for research and development are for PEFCs an increased operating temperature without the need for additional humidification and for DMFC the reduction of methanol transport through the membrane. The use of non-fluorinated polymers aims at a reduction in membrane cost and environmental hazards. Membranes already in industrial product development are considered as well as novel membrane concepts in fundamental research. [source] Effects of Conversion of Dry Tropical Forest to Agricultural Mosaic on Herpetofaunal AssemblagesCONSERVATION BIOLOGY, Issue 2 2008IRERI SUAZO-ORTUÑO atributos de vulnerabilidad; bosque tropical seco; ensambles herpetofaunísticos; modificación del hábitat; mosaico agrícola Abstract:,We explored the impact of forest conversion to agricultural mosaic on anuran, lizard, snake, and turtle assemblages of Neotropical dry forests. Over 2 years, we sampled 6 small watersheds on the west coast of Mexico, 3 conserved and 3 disturbed. The disturbed watersheds were characterized by a mosaic of pastures and cultivated fields (corn, beans, squash) intermingled with patches of different successional stages of dry forest. In each watershed, we conducted 11 diurnal and nocturnal time-constrained searches in 10 randomly established plots. We considered vulnerability traits of species in relation to habitat modification. Eighteen anuran, 18 lizard, 23 snake, and 3 turtle species were recorded. Thirty-six species (58%) occurred in both forest conditions, and 14 (22%) and 12 species (19%) occurred only in the conserved and disturbed sites, respectively. Assemblages responded differently to disturbance. Species richness, diversity, and abundance of lizards were higher in disturbed forests. Anuran diversity and species richness were lower in disturbed forest but abundance was similar in both forest conditions. Diversity, richness, and abundance of turtles were lower in disturbed forest. The structure and composition of snake assemblages did not differ between forest conditions. We considered species disturbance sensitive if their abundance was significantly less in disturbed areas. Four anuran (22%), 2 lizard (11%), and 3 turtle (100%) species were sensitive to disturbance. No snake species was sensitive. The decline in abundance of disturbance-sensitive species was associated with the reduction of forest canopy cover, woody stem cover, roots, and litter-layer ground cover. Anuran species with small body size and direct embryonic development were especially sensitive to forest disturbance. An important goal for the conservation of herpetofauna should be the determination of species traits associated with extinction or persistence in agricultural mosaics. Resumen:,Exploramos el impacto de la conversión de bosques a mosaico agrícola sobre ensambles de lagartijas, serpientes y tortugas de bosques Neotropicales secos. Durante 2 años muestreamos 6 cuencas pequeñas, 3 conservadas y 3 perturbadas, en la costa occidental de México. Las cuencas perturbadas se caracterizaron por un mosaico de pastizales y campos cultivados (maíz, frijol, calabaza) entremezclados con parches de bosque seco en diferentes etapas sucesionales. En cada cuenca, realizamos 11 búsquedas diurnas y nocturnas en 10 parcelas establecidas aleatoriamente. Consideramos los atributos de vulnerabilidad de especies en relación con la modificación del hábitat. Registramos 18 especies de lagartijas, 23 de serpientes y 3 de tortugas. Treinta y seis especies (58%) ocurrieron en ambas condiciones de bosque, y 14 (22%) y 12 (19%) especies solo ocurrieron en los sitios conservados y perturbados, respectivamente. Los ensambles respondieron a la perturbación de manera diferente. La riqueza de especies, la diversidad y la abundancia de lagartijas fueron mayores en los bosques perturbados. La diversidad y riqueza de especies de anuros fueron menores en el bosque perturbado pero la abundancia fue similar en ambas condiciones de bosque. La diversidad, riqueza de especies y abundancia de tortugas fueron menores en el bosque perturbado. La estructura y la composición de los ensambles de serpientes no difirieron entre condiciones de bosque. Consideramos que las especies eran sensibles a la perturbación si su abundancia fue significativamente menor en las áreas perturbadas. Cuatro (22%) especies de anuros, 2 (11%) de lagartijas y 3 (100%) de tortugas fueron sensibles a la perturbación. Ninguna especie de serpiente fue sensible. La declinación en la abundancia de especies sensibles a la perturbación se asoció con la reducción en la cobertura del dosel, de tallos leñosos, raíces y hojarasca. Las especies de anuros de cuerpo pequeño y desarrollo embrionario directo fueron especialmente sensibles a la perturbación del bosque. La determinación de atributos de las especies asociadas con su extinción o persistencia en mosaicos agrícolas debería ser una meta importante para la conservación de la herpetofauna. [source] Versatile fluorescent probes for actin filaments based on the actin-binding domain of utrophinCYTOSKELETON, Issue 11 2007Brian M. Burkel Abstract Actin filaments (F-actin) are protein polymers that undergo rapid assembly and disassembly and control an enormous variety of cellular processes ranging from force production to regulation of signal transduction. Consequently, imaging of F-actin has become an increasingly important goal for biologists seeking to understand how cells and tissues function. However, most of the available means for imaging F-actin in living cells suffer from one or more biological or experimental shortcomings. Here we describe fluorescent F-actin probes based on the calponin homology domain of utrophin (Utr-CH), which binds F-actin without stabilizing it in vitro. We show that these probes faithfully report the distribution of F-actin in living and fixed cells, distinguish between stable and dynamic F-actin, and have no obvious effects on processes that depend critically on the balance of actin assembly and disassembly. Cell Motil. Cytoskeleton 2007. © 2007 Wiley-Liss, Inc. [source] Adults with self-reported learning disabilities in Slovenia: Findings from the international adult literacy survey on the incidence and correlates of learning disabilities in SloveniaDYSLEXIA, Issue 4 2003Lidija Magajna This study of adults with self-reported learning disabilities (SRLD) in Slovenia is part of a larger secondary analysis of the data from the International Literacy Survey project (IALS). The purpose of the study was to examine the characteristics of 79 (2.68%) individuals who reported experiencing learning disabilities and compare them to the general population on a variety of indicators of educational background, employment status, and reading and writing activities at work and at home. The proficiency scores of the SRLD individuals were lower in all three literacy domains (prose, document and quantitative literacy). In prose literacy 77.9% of SRLD adults performed at Level 1 and only 7.8% reached the level necessary for a modern technological society. Experiencing learning disabilities was not related to gender or age, however, results showed significant differences between the levels achieved by older and younger people with SRLD. In SRLD groups aged 40 years and above, no one achieved more than the second level of literacy in any domain. Learning disabilities were reported more frequently in rural areas. SRLD groups achieve significantly lower educational attainment, and lower employment status, with a preference for manual labour or craft. These findings are of critical importance. SRLD people report that poorer literacy skills are an obstacle to their progression in employment. In the Slovene sample, the SRLD group stands out for low scores in quantitative literacy. Results show that they are less active, pick up information only auditorily or in short written form. They need more frequent help from relatives in literacy activities. Interpretation of the IALS data on SRLD presents many problems. These include amongst others, problems in terminology, different background factors, and the validity of self-report measures. However, the study also raises many interesting challenges for future research and policy. Increasing the availability of support, assistance and counselling for adolescents and adults with learning disabilities remains a very important goal for dyslexia and LD policies in Slovenia. Copyright © 2003 John Wiley & Sons, Ltd. [source] LOCAL HETEROZYGOSITY-FITNESS CORRELATIONS WITH GLOBAL POSITIVE EFFECTS ON FITNESS IN THREESPINE STICKLEBACKEVOLUTION, Issue 8 2006Mélissa Lieutenant-Gosselin Abstract The complex interactions between genetic diversity and evolution have important implications in many biological areas including conservation, speciation, and mate choice. A common way to study these interactions is to look at heterozygosity-fitness correlations (HFCs). Until recently, HFCs based on noncoding markers were believed to result primarily from global inbreeding effects. However, accumulating theoretical and empirical evidence shows that HFCs may often result from genes being linked to the markers used (local effect). Moreover, local effect HFCs could differ from global inbreeding effects in their direction and occurrence. Consequently, the investigation of the structure and consequences of local HFCs is emerging as a new important goal in evolutionary biology. In this study of a wild threespine stickleback (Gasterosteus aculeatus) population, we first tested the presence of significant positive or negative local effects of heterozygosity at 30 microsatellites loci on five fitness components: survival, mating success, territoriality, length, and body condition. Then, we evaluated the direction and shape of total impact of local HFCs, and estimated the magnitude of the impacts on fitness using regression coefficients and selection differentials. We found that multilocus heterozygosity was not a reliable estimator of individual inbreeding coefficient, which supported the relevance of single-locus based analyses. Highly significant and temporally stable local HFCs were observed. These were mainly positive, but negative effects of heterozygosity were also found. Strong and opposite effects of heterozygosity are probably present in many populations, but may be blurred in HFC analyses looking for global effects only. In this population, both negative and positive HFCs are apparently driving mate preference by females, which is likely to contribute to the maintenance of both additive and nonadditive genetic variance. [source] Limits of fine-mapping a quantitative traitGENETIC EPIDEMIOLOGY, Issue 2 2003Larry D. Atwood Abstract Once a significant linkage is found, an important goal is reducing the error in the estimated location of the linked locus. A common approach to reducing location error, called fine-mapping, is the genotyping of additional markers in the linked region to increase the genetic information. The utility of fine-mapping for quantitative trait linkage analysis is largely unknown. To explore this issue, we performed a fine-mapping simulation in which the region containing a significant linkage at a 10-centiMorgan (cM) resolution was fine-mapped at 2, 1, and 0.5 cM. We simulated six quantitative trait models in which the proportion of variation due to the quantitative trait locus (QTL) ranged from 0.20,0.90. We used four sampling designs that were all combinations of 100 and 200 families of sizes 5 and 7. Variance components linkage analysis (Genehunter) was performed until 1,000 replicates were found with a maximum lodscore greater than 3.0. For each of these 1,000 replications, we repeated the linkage analysis three times: once for each of the fine-map resolutions. For the most realistic model, reduction in the average location error ranged from 3,15% for 2-cM fine-mapping and from 3,18% for 1-cM fine-mapping, depending on the number of families and family size. Fine-mapping at 0.5 cM did not differ from the 1-cM results. Thus, if the QTL accounts for a small proportion of the variation, as is the case for realistic traits, fine-mapping has little value. Genet Epidemiol 24:99,106, 2003. © 2003 Wiley-Liss, Inc. [source] Fluorimetric Nerve Gas Sensing Based on Pyrene Imines Incorporated into Films and Sub-Micrometer FibersADVANCED FUNCTIONAL MATERIALS, Issue 5 2009Jeremy M. Rathfon Abstract The chemical sensing of nerve gas agents has become an increasingly important goal due to the 1995 terrorist attack in a Tokyo subway as well as national security concerns in regard to world affairs. Chemical detection needs to be sensitive and selective while being facile, portable, and timely. In this paper, a sensing approach using a pyrene imine molecule is presented that is fluorimetric in response. The detection of a chloro-Sarin surrogate is measured at 5 ppmv in less than 1 second and is highly selective towards halogenated organophosphates. The pyrene imine molecule is incorporated into polystyrene films as well as micrometer and sub-micrometer fibers. Using both a direct drawing approach and electrospinning, micrometer and nanofibers can be easily manufactured. Applications for functional sensing micrometer and nanofibers are envisioned for optical devices and photonics in addition to solution and airflow sensing devices. [source] Solution-Processible Phosphorescent Blue Dendrimers Based on Biphenyl-Dendrons and Fac -tris(phenyltriazolyl)iridium(III) Cores,ADVANCED FUNCTIONAL MATERIALS, Issue 19 2008Shih-Chun Lo Abstract Solution-processible saturated blue phosphorescence is an important goal for organic light-emitting diodes (OLEDs). Fac -tris(5-aryltriazolyl)iridium(III) complexes can emit blue phosphorescence at room temperature. Mono- and doubly dendronized fac -tris(1-methyl-5-phenyl-3- n -propyl-1H -[1,2,4]triazolyl)iridium(III) 1 and fac -tris{1-methyl-5-(4-fluorophenyl)-3- n -propyl-1H -[1,2,4]triazolyl}iridium(III) 4 with first generation biphenyl-based dendrons were prepared. The dendrimers emitted blue light at room temperature and could be solution processed to form thin films. The doubly dendronized 3 had a film photoluminescence quantum yield of 67% and Commission Internationale de l'Eclairage (CIE) coordinates of (0.17, 0.33). OLEDs comprised of a neat film of dendrimer 3 and an electron transport layer achieved a brightness of 142,cd m,2 at 3.8,V with an external quantum efficiency of 7.9%, and CIE coordinates of (0.18, 0.35). Attachment of the fluorine atom to the emissive core had the effect of moving the luminescence to shorter wavelengths but also quenched the luminescence of the mono- and doubly dendronized dendrimers. [source] Towards consensus in the long-term management of relapse prevention in schizophreniaHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 3 2005M. Taylor Abstract Approach to developing guidance When developing guidance for the long-term management of schizophrenia, one approach is to adopt a proactive strategy that sets out clear treatment goals and strategies. This should involve a broad view being taken, embracing overall mental and physical well-being rather than simply the absence of illness. Although relapse prevention is an important goal of any long-term management strategy, there are other aspects that need to be considered, such as reintegration into society, regaining independence and quality of life. Current treatment To help achieve these goals, a range of interventions can be incorporated into long-term management strategies for schizophrenia, including pharmacological interventions, psychosocial therapies and alliance-building initiatives. The current UK National Institute for Clinical Excellence guidelines already recommend that continuous therapy should be practised using an atypical (second-generation) antipsychotic drug, whenever possible, in preference to older typical drugs. The launch of the first long-acting atypical antipsychotic is an interesting new advance that may benefit many patients with schizophrenia. Psychosocial interventions, particularly family-based therapies, as well as cognitive behavioural and compliance therapies, when used alongside antipsychotics, have been shown to reduce relapse rates dramatically and to assist in social reintegration. In addition, forging collaborative alliances with patients and their carers can help to demystify schizophrenia and empower patients to take responsibility for their illness. Consensus statement This article outlines a consensus reached by a panel of leading UK healthcare professionals working with schizophrenia brought together to discuss long-term management strategies. Copyright © 2005 John Wiley & Sons, Ltd. [source] Medical management of patients with aneurysmal subarachnoid haemorrhageINTERNATIONAL JOURNAL OF STROKE, Issue 3 2008Gabriel J. E. Rinkel Abstract Treating patients with aneurysmal subarachnoid haemorrhage is taking care of acutely ill patients, and should be performed in centres where a multidisciplinary team is available 24 hours a day 7 days a week, and where enough patients are managed to maintain and improve standards of care. There is no medical management that improves outcome by reducing the risk of rebleeding, therefore occlusion of the aneurysm, nowadays preferably by means of coiling, remains an important goal in treating patients with aneurysms. Because the poor outcome after subarachnoid haemorrhage is caused to a large extent by complications other than rebleeding, proper medical management to prevent and treat these complications is therefore essential. On basis of the available evidence, oral (not intravenous) nimodipine should be standard care in patients with subarachnoid haemorrhage. It is rational to refrain from treating hypertension unless cardiac failure develops and to aim for normovolaemia, even in case of hyponatraemia. There is no evidence for prophylactic hypervolaemia, and the strategy of hypervolaemia and hypertension in patients with secondary cerebral ischaemia is based on case reports and uncontrolled observational series of patients. Magnesium sulphate and statins are promising therapies, and large trials on effectiveness in improving clinical outcome are underway. There is no evidence for prophylactic use of anti epileptic drugs, and routine use of corticosteroids should be avoided. [source] Nonparametric Varying-Coefficient Models for the Analysis of Longitudinal DataINTERNATIONAL STATISTICAL REVIEW, Issue 3 2002Colin O. Wu Summary Longitudinal methods have been widely used in biomedicine and epidemiology to study the patterns of time-varying variables, such as disease progression or trends of health status. Data sets of longitudinal studies usually involve repeatedly measured outcomes and covariates on a set of randomly chosen subjects over time. An important goal of statistical analyses is to evaluate the effects of the covariates, which may or may not depend on time, on the outcomes of interest. Because fully parametric models may be subject to model misspecification and completely unstructured nonparametric models may suffer from the drawbacks of "curse of dimensionality", the varying-coefficient models are a class of structural nonparametric models which are particularly useful in longitudinal analyses. In this article, we present several important nonparametric estimation and inference methods for this class of models, demonstrate the advantages, limitations and practical implementations of these methods in different longitudinal settings, and discuss some potential directions of further research in this area. Applications of these methods are illustrated through two epidemiological examples. Résumé Modèles non-paramétriques à coefficients variables pour l'analyse de données longitudinales Les méthodes longitudinales ont été largement utilisées en biomédecine et en épidémiologie pour étudier les modèles de variables variant dans le temps, du type progression de maladie ou tendances détat de santé. Les ensembles de données d'études longitudinales comprennent généralement des ésultats de mesures répétées et des covariables sur un ensemble de sujets choisis au hasard dans le temps. Un objectif important des analyses statistiques consisteàévaluer les effets des covariables, qui peuvent ou non dépendre du temps, sur les résultats d'intérêt. Du fait que des modèles entièrement paramétriques peuvent faire l'objet d'erreur de spécification de modèle et que des modèles non-paramétriques totalement non-structurés peuvent souffrir des inconvénients de la «malédiction de dimensionnalité», les modèles à coefficients variables sont une classe de modèles structurels non-paramétriques particulièrement utiles dans les analyses longitudinales. Dans cet article, on présente plusieurs estimations non-paramétriques importantes, ainsi que des méthodes d'inférence pour cette classe de modéles, on démontre les avantages, limites et mises en ,uvre pratiques de ces méthodes dans différents contextes longitudinaux et l'on traite de certaines directions possibles pour de plus amples recherches dans ce domaine. Des applications de ces méthodes sont illustrées à travers deux exemples épidémiologiques. [source] Climate-based models of spatial patterns of species richness in Egypt's butterfly and mammal faunaJOURNAL OF BIOGEOGRAPHY, Issue 11 2009Tim Newbold Abstract Aim, Identifying areas of high species richness is an important goal of conservation biogeography. In this study we compared alternative methods for generating climate-based estimates of spatial patterns of butterfly and mammal species richness. Location, Egypt. Methods, Data on the occurrence of butterflies and mammals in Egypt were taken from an electronic database compiled from museum records and the literature. Using Maxent, species distribution models were built with these data and with variables describing climate and habitat. Species richness predictions were made by summing distribution models for individual species and by modelling observed species richness directly using the same environmental variables. Results, Estimates of species richness from both methods correlated positively with each other and with observed species richness. Protected areas had higher species richness (both predicted and actual) than unprotected areas. Main conclusions, Our results suggest that climate-based models of species richness could provide a rapid method for selecting potential areas for protection and thus have important implications for biodiversity conservation. [source] Classically and alternatively activated macrophages contribute to tissue remodelling after myocardial infarctionJOURNAL OF CELLULAR AND MOLECULAR MEDICINE, Issue 9b 2009C. Troidl Abstract An important goal in cardiology is to minimize myocardial necrosis and to support a discrete but resilient scar formation after myocardial infarction (MI). Macrophages are a type of cells that influence cardiac remodelling during MI. Therefore, the goal of the present study was to investigate their transcriptional profile and to identify the type of activation during scar tissue formation. Ligature of the left anterior descending coronary artery was performed in mice. Macrophages were isolated from infarcted tissue using magnetic cell sorting after 5 days. The total RNA of macrophages was subjected to microarray analysis and compared with RNA from MI and LV-control. mRNA abundance of relevant targets was validated by quantitative real-time PCR 2, 5 and 10 days after MI (qRT-PCR). Immunohistochemistry was performed to localize activation type-specific proteins. The genome scan revealed 68 targets predominantly expressed by macrophages after MI. Among these targets, an increased mRNA abundance of genes, involved in both the classically (tumour necrosis factor ,, interleukin 6, interleukin 1,) and the alternatively (arginase 1 and 2, mannose receptor C type 1, chitinase 3-like 3) activated phenotype of macrophages, was found 5 days after MI. This observation was confirmed by qRT-PCR. Using immunohistochemistry, we confirmed that tumour necrosis factor ,, representing the classical activation, is strongly transcribed early after ligature (2 days). It was decreased after 5 and 10 days. Five days after MI, we found a fundamental change towards alternative activation of macrophages with up-regulation of arginase 1. Our results demonstrate that macrophages are differentially activated during different phases of scar tissue formation after MI. During the early inflammatory phase, macrophages are predominantly classically activated, whereas their phenotype changes during the important transition from inflammation to scar tissue formation into an alternatively activated type. [source] A literature review of spirituality in coping with early-stage Alzheimer's diseaseJOURNAL OF CLINICAL NURSING, Issue 5a 2008Linda Beuscher PhD Aims., This paper presents a literature review focusing on the use of spirituality in coping by older persons with early-stage Alzheimer's disease from their perspectives. The purpose of this literature review is to examine the existing body of knowledge about spirituality in coping with Alzheimer's disease and to apply a spiritual framework of coping in organizing the literature to identify themes and gaps in knowledge. Background., Despite the abundance of Alzheimer's disease research, little is known about how older persons with this devastating disease cope with the consequential losses. Maintaining a sense of normalcy and preserving self-worth are coping strategies reported by older persons with early-stage Alzheimer's disease. As spirituality is an effective coping resource for older persons with numerous psychological and personal losses in their lives, it may be an important coping resource for person with Alzheimer's disease. Method., A literature search was conducted to find research published between 1990,2006 aimed at understanding spirituality in coping with early-stage Alzheimer's disease. Conclusions., Six research studies were reviewed. Findings suggest that persons with early-stage Alzheimer's disease draw from their spirituality and faith to find meaning and courage in facing the challenges of cognitive losses. Furthermore, they are able to provide rich information about their spirituality and the psychosocial aspects of living with Alzheimer's disease. Limited empirical knowledge compels the need for future research to explore how spirituality is utilized in coping with early-stage Alzheimer's disease. Relevance to clinical practice., Enhancing persons' abilities to cope effectively with their diseases is an important goal of nursing care. Understanding how older persons with Alzheimer's disease cope with their memory loss is critical to the development of evidence-based interventions to minimize the stress of living with this disease. [source] Esthetic Correction of Gingival Recession Using a Modified Tunnel Technique and an Acellular Dermal Connective Tissue AllograftJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 1 2002DOUGLAS H. MAHN DDS ABSTRACT Esthetic correction of gingival recession is an important goal of periodontal therapy. This article describes a surgical technique that combines a modified tunnel technique and an acellular dermal connective tissue allograft. With the aid of vertical incisions, a tunnel is created under the buccal mucosa of the affected tooth. These incisions enable easy access for graft placement and create mobility for gingival coronal positioning. The use of an acellular dermal connective tissue allograft eliminates the need for a surgical palatal donor site. This minimizes postsurgical complications. CLINICAL SIGNIFICANCE The combination of a modified tunnel technique and an acellular dermal connective tissue allograft permits esthetic root coverage in a manner that reduces postsurgical complications. [source] Breeding upland rice for drought resistanceJOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE, Issue 6 2008Jérôme Bernier Abstract Upland rice, produced by smallholder farmers, is the lowest-yielding rice production system. Drought stress is the most severe abiotic constraint in upland rice. Improving productivity of rice in the upland ecosystem is essential to meet rice food security needs of impoverished upland communities. Breeding drought-resistant upland rice is therefore an increasingly important goal. Numerous secondary characters have been suggested to help plant breeders in their selections. Most of these traits are not used in selection, as they are not practical for selection purposes, exhibit low heritability, or are not highly correlated with grain yield. The use of managed drought stress, where drought stress can be imposed at specific periods, has been shown to increase the heritability of yield under stress to values similar to those obtained for yield in well-watered conditions. It has now been demonstrated that drought-tolerant upland rice can be bred by directly selecting for yield in stress environments. The use of molecular markers to perform selection may eventually provide plant breeders with more efficient selection methods. To date, many quantitative trait loci (QTL) for drought resistance have been identified in rice, but few are suitable for use in marker-assisted selection. However, large-effect drought resistance QTL have now been identified and may enable effective use of marker-assisted selection for drought resistance. Copyright © 2008 Society of Chemical Industry [source] Mutation Causing von Willebrand's Disease in Scottish TerriersJOURNAL OF VETERINARY INTERNAL MEDICINE, Issue 1 2000Patrick J. Venta Von Willebrand's Disease (vWD) in the Scottish Terrier breed is a serious, often fatal, hereditary bleeding disorder. Elimination of the mutated gene by selective breeding is an important goal for the health of this breed. Although the standard protein-based tests are accurate for identification of affected Scottish Terriers, they are not reliable for the identification of carriers of the mutant gene unless multiple replicate assays are performed. A simple, highly accurate test for carriers of the disease is needed so that veterinarians can counsel clients on which animals to use in their breeding programs. The complete coding region of von Willebrand factor (vWF) complementary DNA (cDNA) was sequenced from an affected animal, and a single base deletion in the codon for amino acid 85 of the prepro-vWF cDNA that leads to Scottish Terrier vWD was identified. A highly accurate polymerase chain reaction assay was developed that can distinguish homozygous normal animals from those that are homozygous affected or heterozygous. In a voluntary survey of 87 animals provided by Scottish Terrier owners, 15 were carriers and 4 were affected with vWD, 2 of which had previously been shown to have undetectable vWF. The determination of the complete canine vWF cDNA sequence should facilitate the identification of additional vWD alleles in other breeds and other species. [source] User participation when using milieu therapy in a psychiatric hospital in Norway: a mission impossible?NURSING INQUIRY, Issue 4 2009Christine Oeye In the past decade, the Norwegian government has emphasized user participation as an important goal in the care of mentally ill patients, through governmental strategic plans. At the same time, the governmental documents request normalization of psychiatric patients, including the re-socialization of psychiatric patients back into society outside the psychiatric hospital. Milieu therapy is a therapeutic tool to ensure user participation and re-socialization. Based on an ethnographic study in a long-term psychiatric ward in a psychiatric hospital, we identified how staff tried to implement user participation in their milieu-oriented therapy work. We have identified three major tensions and challenges in implementing user participation in milieu-therapeutic work. First, it is difficult to implement individual-based user participation and at the same time take collective house rules and codes of conduct into consideration. Second, user participation proved a difficulty when patients' viewpoints challenged staff judgements on proper conduct and goals for which patients might aim. Third, user participation becomes a challenge when trying to establish relationships based on equality when using milieu therapy in a biomedical hierarchical hospital structure. These tensions and challenges are seen in light of paradoxical political frames and demands on one side, and milieu therapy as a complex tradition anchored in different ideologies on the other. [source] A Survey of the Practice of Lead Extraction in the United StatesPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 6 2010CHARLES A. HENRIKSON M.D. Background:,Endovascular lead extraction is an important component of the management of patients with chronically implanted arrhythmia control devices. Although it is associated with the potential for significant morbidity and mortality, there is little information about its scope and practice. Methods:,We surveyed 1,000 physician members of the Heart Rhythm Society via e-mail solicitation. Results:,Of the 252 respondents (25%), 221 (88%) reported either performing extractions themselves (63%), or having privileges at a hospital where extractions are performed (25%). Electrophysiologists perform extractions at most sites (83%) but cardiac surgeons perform endovascular lead extraction at a significant minority of sites (20%). Most respondents report low annual volumes of extractions at their site: 15% reported <10 procedures/year, 42% 10,25 procedures/year, 23% 26,50 procedure/year, and only 19% reported >50 procedures/year. Thirty-six percent of respondents reported that extractions were done in the operating room (OR) with surgeon present or immediately available, 39% in the electrophysiology (EP) lab with surgeon and OR identified and available, and 25% in EP lab without a surgeon or OR identified. The overall risks of lead extraction were felt to be 1,5% of major complication and 0.5,1% of mortality, roughly in line with published data. Conclusions:,While there is agreement as to the risk of major complication and death from lead extraction, the degree of surgical availability varies considerably. The new guidelines document recommends the ability to promptly initiate an emergent surgical procedure, and this should be an important goal for all extractionists. (PACE 2010; 33:721,726) [source] Non-adherence to medications following pediatric liver transplantationPEDIATRIC TRANSPLANTATION, Issue 6 2004Eyal Shemesh Abstract:, Non-adherence to medications is a leading cause of organ loss and morbidity in children and adolescents who had a liver transplant. Yet there are very few published studies about ways to detect whether patients are taking their medications or not, and about treatment options to improve adherence. The Pediatric Liver/Liver Transplant Program at Mount Sinai developed clinical and research programs that evaluate adherence. We review initial results from these programs. Clinic patients participate in an adherence-monitoring program that involves standardized assessments by patients, parents, clinicians, and routine examinations of medication blood levels. A research program adds an electronic monitoring device (MEMS-caps©, AARDEX/APREX, Switzerland) and examines the use of azathioprine metabolites as predictors for non-adherence. Patients receive a thorough psychosocial evaluation to identify potential risk factors for non-adherence. Preliminary results indicate that an objective adherence detection method has to be incorporated into practice if non-adherence is to be reliably detected (clinicians' impressions and patients' reports are not sufficient). A risk factor for non-adhernce, post-traumatic stress disorder, emerges as a potential target for intervention. It is possible to integrate a formal mechanism to assess adherence into the work of a liver/liver transplant clinic. We hope that the presented program will inspire clinicians in the community and other programs to regard the assessment and improvement of adherence to medications as an important goal in the management of children who had a transplant. [source] Photosynthetic limitations in olive cultivars with different sensitivity to salt stressPLANT CELL & ENVIRONMENT, Issue 4 2003F. LORETO ABSTRACT Olive (Olea europea L) is one of the most valuable and widespread fruit trees in the Mediterranean area. To breed olive for resistance to salinity, an environmental constraint typical of the Mediterranean, is an important goal. The photosynthetic limitations associated with salt stress caused by irrigation with saline (200 mm) water were assessed with simultaneous gas-exchange and fluorescence field measurements in six olive cultivars. Cultivars were found to possess inherently different photosynthesis when non-stressed. When exposed to salt stress, cultivars with inherently high photosynthesis showed the highest photosynthetic reductions. There was no relationship between salt accumulation and photosynthesis reduction in either young or old leaves. Thus photosynthetic sensitivity to salt did not depend on salt exclusion or compartmentalization in the old leaves of the olive cultivars investigated. Salt reduced the photochemical efficiency, but this reduction was also not associated with photosynthesis reduction. Salt caused a reduction of stomatal and mesophyll conductance, especially in cultivars with inherently high photosynthesis. Mesophyll conductance was generally strongly associated with photosynthesis, but not in salt-stressed leaves with a mesophyll conductance higher than 50 mmol m,2 s,1. The combined reduction of stomatal and mesophyll conductances in salt-stressed leaves increased the CO2 draw-down between ambient air and the chloroplasts. The CO2 draw-down was strongly associated with photosynthesis reduction of salt-stressed leaves but also with the variable photosynthesis of controls. The relationship between photosynthesis and CO2 draw-down remained unchanged in most of the cultivars, suggesting no or small changes in Rubisco activity of salt-stressed leaves. The present results indicate that the low chloroplast CO2 concentration set by both low stomatal and mesophyll conductances were the main limitations of photosynthesis in salt-stressed olive as well as in cultivars with inherently low photosynthesis. It is consequently suggested that, independently of the apparent sensitivity of photosynthesis to salt, this effect may be relieved if conductances to CO2 diffusion are restored. [source] Comparison of binding energies of SrcSH2-phosphotyrosyl peptides with structure-based prediction using surface area based empirical parameterizationPROTEIN SCIENCE, Issue 10 2000Denise A. Henriques Abstract The prediction of binding energies from the three-dimensional (3D) structure of a protein,ligand complex is an important goal of biophysics and structural biology. Here, we critically assess the use of empirical, solvent-accessible surface area-based calculations for the prediction of the binding of Src-SH2 domain with a series of tyrosyl phosphopeptides based on the high-affinity ligand from the hamster middle T antigen (hmT), where the residue in the pY+3 position has been changed. Two other peptides based on the C-terminal regulatory site of the Src protein and the platelet-derived growth factor receptor (PDGFR) are also investigated. Here, we take into account the effects of proton linkage on binding, and test five different surface area-based models that include different treatments for the contributions to conformational change and protein solvation. These differences relate to the treatment of conformational flexibility in the peptide ligand and the inclusion of proximal ordered solvent molecules in the surface area calculations. This allowed the calculation of a range of thermodynamic state functions (,Cp, ,S, ,H, and ,G) directly from structure. Comparison with the experimentally derived data shows little agreement for the interaction of SrcSH2 domain and the range of tyrosyl phosphopeptides. Furthermore, the adoption of the different models to treat conformational change and solvation has a dramatic effect on the calculated thermodynamic functions, making the predicted binding energies highly model dependent. While empirical, solvent-accessible surface area based calculations are becoming widely adopted to interpret thermodynamic data, this study highlights potential problems with application and interpretation of this type of approach. There is undoubtedly some agreement between predicted and experimentally determined thermodynamic parameters; however, the tolerance of this approach is not sufficient to make it ubiquitously applicable. [source] Localization and targeting of the VP14 epoxy-carotenoid dioxygenase to chloroplast membranesTHE PLANT JOURNAL, Issue 5 2001Bao-Cai Tan Summary Abscisic acid (ABA) is a key regulator of seed dormancy and plant responses to environmental challenges. ABA is synthesized via an oxidative cleavage of 9- cis epoxy-carotenoids, the first committed and key regulatory step in the ABA biosynthetic pathway. Vp14 of maize encodes an epoxy-carotenoid dioxygenase that is soluble when expressed in E. coli. An important goal has been to determine how the soluble VP14 protein is targeted to epoxy-carotenoid substrates that are located in the thylakoid and envelope membranes of chloroplasts and other plastids. Using an in vitro chloroplast import assay, we have shown that VP14 is imported into chloroplasts with cleavage of a short stroma-targeting domain. The mature VP14 exists in two forms, one which is soluble in stroma and the other bound to thylakoid membranes. Analysis of a series of truncated VP14 mutants mapped the membrane targeting signal to the 160 amino acid N-terminal sequence. A putative amphipathic ,-helix within this region is essential, but not sufficient, for the membrane targeting. Either deletion of or insertion of helix breaking residues into this region abolished the membrane binding, whereas a chimeric protein carrying just the amphipathic region fused with bacterial glutathione S -transferase failed to associate with the thylakoid membrane. The membrane-bound VP14 was partially resistant to chaotropic washes such as 0.1 m Na2CO3 (pH 11.5) and 6 m urea. Unlabelled recombinant VP14 inhibited the tight binding of imported VP14, suggesting that VP14 is associated with specific components of the thylakoid membrane. [source] The Diagnostic Conundrum and Liver Transplantation Outcome for Combined Hepatocellular-CholangiocarcinomaAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010C. Panjala Combined hepatocellular-cholangiocarcinoma (cHCC-CC) is a rare primary liver malignancy with mixed hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) histological features. It is almost impossible to obtain an accurate, preoperative noninvasive diagnosis of cHCC-CC with tumor markers or cross-sectional abdominal imaging due to the mixed histological features. Despite these difficulties, accurate cHCC-CC diagnosis remains an important goal with prognostic significance. In our study, we retrospectively reviewed the tumor markers: AFP and CA 19-9, and cross-sectional liver imaging, in light of liver explant findings, to identify and characterize cHCC-CC features followed by liver transplantation (LT) outcome analysis. The results from this 12 patient cohort failed to identify characteristic features for cHCC-CC. None of the imaging features helped to identify the cHCC-CC tumor and they mimicked either HCC or CC, depending on the degree of glandular differentiation expressed histologically. In our cHCC-CC LT recipients, the 1-, 3- and 5-year cumulative survival probabilities were 79%, 66% and 16%, respectively with a 5-year survival comparable to or better than LT for intrahepatic CC but poorer than LT for HCC following the Milan criteria. Conceivably explained by its cholangiocarcinoma component the LT outcome for this rare and hard to diagnose tumor appears poor. [source] Teaching Statistical Consulting Before Statistical MethodologyAUSTRALIAN & NEW ZEALAND JOURNAL OF STATISTICS, Issue 2 2003Ross H. Taplin Abstract This paper outlines and discusses the advantages of an ,Introduction to Statistical Consulting' course (ISC) that exposes students to statistical consulting early in their studies. The course is intended for students before, or while, they study their units in statistical techniques, and assumes only a first-year introductory statistics unit. The course exposes undergraduate students to the application of statistics and helps develop statistical thinking. An important goal is to introduce students to work as a statistician early in their studies because this motivates some students to study statistics further and provides a framework to motivate the learning of further statistical techniques. The ISC has proved popular with students, and this paper discusses the reasons for this popularity and the benefits of an ISC to statistical education and the statistics profession. [source] Evaluation of software for introducing protein structureBIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 5 2010Visualization, simulation Abstract Communicating an understanding of the forces and factors that determine a protein's structure is an important goal of many biology and biochemistry courses at a variety of levels. Many educators use computer software that allows visualization of these complex molecules for this purpose. Although visualization is in wide use and has been associated with student learning, it is quite challenging to develop visualizations that allow students to interactively observe the effects of altered amino acid sequence on protein structure. A software simulation, the protein investigator (PI), has been developed to specifically facilitate this type of exploration. When using the PI, students enter or edit an amino acid sequence; the software then simulates its folding in two dimensions using the major forces involved in protein structure. This study explores freshman undergraduate students' use of visualization and simulation when learning about protein structure. It also evaluates some of the learning outcomes from these two approaches. Our results show that simulation leads to similar learning outcomes as visualization. Because simulation allows a more interactive exploration, a combination of the two approaches may be an effective approach to introducing the basic principles of protein structure. [source] Helical Chiral Pyridine N -Oxides: A New Family of Asymmetric CatalystsCHEMISTRY - A EUROPEAN JOURNAL, Issue 30 2009Jinshui Chen Dr. Abstract Optically active chiral alkyl chlorides are valuable compounds because of their bioactivity and versatile synthetic utility. Accordingly, the ring opening of epoxides with a chloride nucleophile stands as an important goal in asymmetric catalysis. We describe herein recent advances in the design and development of chiral pyridine N -oxide catalysts for the enantioselective synthesis of chlorohydrins. [source] Photophysical Aspects of Single-Molecule Detection by Two-Photon Excitation with Consideration of Sequential Pulsed IlluminationCHEMPHYSCHEM, Issue 5 2004R. Niesner Abstract An important goal in single molecule fluorescence correlation spectroscopy is the theoretical simulation of the fluorescence signal stemming from individual molecules and its autocorrelation function. The simulation approaches developed up to now are based exclusively on continuous-wave (cw) illumination and consequently on cw-excitation. However, this approximation is no longer valid in the case of two-photon excitation, for which pulsed illumination is usually employed. We present a novel theoretical model for the simulation of the fluorescence signal of single molecules and its autocorrelation function with consideration of the time dependence of the excitation flux and thus of all illumination-dependent photoprocesses: two-photon excitation, induced emission and photobleaching. Further important characteristics of our approach are the consideration of the dependence of the photobleaching rate on illumination and the low intersystem-crossing rates of the studied coumarins. Moreover, using our approach, we can predict quantitatively the effect of the laser pulse width on the fluorescence signal of a molecule, that is, the contributions of the photobleaching and saturation effects, and thus we can calculate the optimal laser pulse width. The theoretical autocorrelation functions were fitted to the experimental data, and we could ascertain a good agreement between the resulting and the expected parameters. The most important parameter is the photobleaching constant ,, the cross section of the transition Sn,S1, which characterises the photostability of the molecules independent of the experimental conditions. Its value is 1.7×10,23 cm2 for coumarin 153 and 5×10,23 cm2 for coumarin 314. [source] Overview of the relationship between ischemia and congestive heart failureCLINICAL CARDIOLOGY, Issue S4 2000PH.D., Willem J. Remme M.D. Abstract Ischemic heart disease is the principal etiology of heart failure in the Western world. Myocardial ischemia is important in cardiac remodeling, a process that leads to a progressive change in the shape and size of the heart and significantly worsens the prognosis of patients with heart failure. Preventing ischemic events, therefore, is an important goal in the management of patients with coronary artery disease. Statins have been shown to reduce the number of ischemic events in these patients, whereas the benefit of beta-blocker and aldosterone antagonist therapy on ischemic causes of heart failure remains unclear. Several large trials involving patients with asymptomatic left ventricular dysfunction after myocardial infarction or heart failure have shown that angiotensin-converting enzyme (ACE) inhibitors reduce the incidence of progressive heart failure, death, and ischemic events, thus establishing ACE inhibitors as first-line therapy for these patients. Other lines of evidence have suggested that ACE inhibitor therapy may also benefit patients with preserved left ventricular function, a hypothesis that is being evaluated in three large, controlled, randomized trials. One of these trials, the Heart Outcomes Prevention Evaluation (HOPE) study, was terminated prematurely because it demonstrated the significant positive effects of the ACE inhibitor ramipril on cardiovascular outcomes in patients with coronary artery disease and preserved left ventricular function. A growing body of data confirms the relationship between ischemia and heart failure and the benefits of ACE inhibitor treatment in a broad range of high-risk patients. [source] Thymoglobulin induction and steroid avoidance in cardiac transplantation: results of a prospective, randomized, controlled studyCLINICAL TRANSPLANTATION, Issue 1 2008Mohamad H Yamani Abstract:, Background:, Chronic use of corticosteroids (CS) following transplantation is associated with significant long-term morbidities. Minimizing exposure to CS to improve long-term outcomes, without compromising allograft function, remains an important goal in transplantation. Objectives:, This single-center, prospective, randomized, open-label study was designed to evaluate the efficacy of Thymoglobulin® as part of a CS-sparing regimen in cardiac transplantation. Methods:, Thirty-two low-risk cardiac transplant patients were randomized in a 1:1 ratio to receive either a Thymoglobulin-based CS-avoidance regimen (CS-avoidance group; n = 16) or a long-term CS-based regimen with no antibody induction (control group; n = 16). Pulse CS therapy was used for the treatment of acute cellular rejection in both groups. Results:, Baseline characteristics were similar between groups. At one yr, there was no significant difference in the mean incidence of acute cellular rejection (,3A) episodes between the CS-avoidance and control groups, 0.81 ± 1.05 and 1.07 ± 1.03, respectively. Importantly, the CS-avoidance patients had significant improvement in muscle strength and less bone loss compared with the control patients during the first six months post-transplant. Conclusions:, CS-avoidance regimen with Thymoglobulin induction appeared to be safe and effective in cardiac transplantation. Further studies are required to demonstrate the long-term safety and benefits of such a regimen. [source] | ||||||||||||||||||||||||||||||||||||||||