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Critical Areas (critical + area)
Selected AbstractsDifferential Expression Patterns of Runx2 Isoforms in Cranial Suture MorphogenesisJOURNAL OF BONE AND MINERAL RESEARCH, Issue 5 2001Mi-Hyun Park Abstract Runx2 (previously known as Cbfa1/Pebp2,A/AML3), a key transcription factor in osteoblast differentiation, has at least two different isoforms using alternative promoters, which suggests that the isoforms might be expressed differentially. Haploinsufficiency of the Runx2 gene is associated with cleidocranial dysplasia (CCD), the main phenotype of which is inadequate development of calvaria. In spite of the biological relevance, Runx2 gene expression patterns in developing calvaria has not been explored previously, and toward this aim we developed three probes: pRunx2, which comprises the common coding sequence of Runx2 and hybridizes with all isoforms; pPebp2,A, which specifically hybridizes with the isoform transcribed with the proximal promoter; and pOsf2, which hybridizes with the isoform transcribed with the distal promoter. These probes were hybridized with tissue sections of mouse calvaria taken at various time points in development. Runx2 expression was localized to the critical area of cranial suture closure, being found in parietal bones, osteogenic fronts, and sutural mesenchyme. Pebp2,A and Osf2 showed tissue-specific expression patterns. The sites of Pebp2,A expression were almost identical to that of pRunx2 hybridization but expression was most intense in the sutural mesenchyme, where undifferentiated mesenchymal cells reside. The Osf2 isoform was strongly expressed in the osteogenic fronts, as well as in developing parietal bones, where osteopontin (OP) and osteocalcin (OC) also were expressed. However, in contrast to Pebp2,A, Osf2 expression did not occur in sutural mesenchyme. Pebp2,A also was expressed prominently in primordial cartilage that is found under the sutural mesenchyme and is not destined to be mineralized. Thus, Osf2 isoforms contribute to events later in osteoblast differentiation whereas the Pebp2,A isoform participates in a wide variety of cellular activities ranging from early stages of osteoblast differentiation to the final differentiation of osteoblasts. [source] Advancing Alcohol Biomarkers ResearchALCOHOLISM, Issue 6 2010Cynthia F. Bearer Biomarkers to detect past alcohol use and identify alcohol-related diseases have long been pursued as important tools for research into alcohol use disorders as well as for clinical and treatment applications and other settings. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) sponsored a workshop titled "Workshop on Biomarkers for Alcohol-Induced Disorders" in June 2008. The intent of this workshop was to review and discuss recent progress in the development and implementation of biomarkers for alcohol use and alcohol-related disorders with a goal to formulate a set of recommendations to use to stimulate and advance research progress in this critical area of alcoholism research. Presentations at this workshop reviewed the current status of alcohol biomarkers, providing a summary of the history of biomarkers and the major goals of alcohol biomarker research. Moreover, presentations provided a comprehensive overview of the current status of several well-recognized biomarkers of alcohol use, a summary of recent studies to characterize novel biomarkers and their validation, along with perspectives and experiences from other NIH institutes and from other federal agencies and industry, related to regulatory issues. Following these presentations, a panel discussion focused on a set of issues presented by the organizers of this workshop. These discussion points addressed: (i) issues related to strategies to be adopted to stimulate biomarker discovery and application, (ii) the relevance of animal studies in biomarker development and the status of biomarkers in basic science studies, and (iii) issues related to the opportunities for clinical and commercial applications. This article summarizes these perspectives and highlights topics that constituted the basis for recommendations to enhance alcohol biomarker research. [source] Systematic multidisciplinary approach to reporting perinatal mortality: Lessons from a five-year regional reviewAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 5 2009Alison L. KENT Background:, Because of differences in reporting criteria throughout the world, comparing perinatal mortality rates and identifying areas of concern can be complicated and imprecise. Aims:, To detail the systematic approach to reporting perinatal deaths and to identify any significant differences in outcomes in the Australian Capital Territory (ACT). Methods:, Review of perinatal deaths from 2001 to 2005 in the ACT using the Australian and New Zealand Antecedent Classification of Perinatal Mortality (ANZACPM) and the Australian and New Zealand Neonatal Death Classification (ANZNDC) systems. Results:, ACT residents' perinatal mortality rate was 10.6 per 1000 total births, fetal death rate 7.5 per 1000 total births and neonatal death rate 3.2 per 1000 live births. The three leading antecedent causes of perinatal death were congenital anomalies, spontaneous preterm birth and unexplained antepartum death. The three leading causes of neonatal death were extreme prematurity, cardiorespiratory disorders and congenital anomalies. Multiple births attributed to 20% (65 of 321) of perinatal deaths. Perinatal autopsy was performed in 50% of cases, but in only 64% of unexplained antepartum deaths. Conclusions:, Causes of perinatal death for the ACT and surrounding New South Wales region are similar to other states using this classification system. The following are considered important lessons to promote accurate perinatal mortality reporting: (i) a universal reporting system for Australia utilising a multidisciplinary team; (ii) a high perinatal autopsy rate, especially in the critical area of antepartum death with no identifiable cause; and (iii) standardised definitions for avoidability. Attention to these areas may prompt further research and changes in practice to further reduce perinatal mortality. [source] An economic comparison of different fermentation configurations to convert corn stover to ethanol using Z. mobilis and SaccharomycesBIOTECHNOLOGY PROGRESS, Issue 1 2010Abhijit Dutta Abstract Numerous routes are being explored to lower the cost of cellulosic ethanol production and enable large-scale production. One critical area is the development of robust cofermentative organisms to convert the multiple, mixed sugars found in biomass feedstocks to ethanol at high yields and titers without the need for processing to remove inhibitors. Until such microorganisms are commercialized, the challenge is to design processes that exploit the current microorganisms' strengths. This study explored various process configurations tailored to take advantage of the specific capabilities of three microorganisms, Z. mobilis 8b, S. cerevisiae, and S. pastorianus. A technoeconomic study, based on bench-scale experimental data generated by integrated process testing, was completed to understand the resulting costs of the different process configurations. The configurations included whole slurry fermentation with a coculture, and separate cellulose simultaneous saccharification and fermentation (SSF) and xylose fermentations with none, some or all of the water to the SSF replaced with the fermented liquor from the xylose fermentation. The difference between the highest and lowest ethanol cost for the different experimental process configurations studied was $0.27 per gallon ethanol. Separate fermentation of solid and liquor streams with recycle of fermented liquor to dilute the solids gave the lowest ethanol cost, primarily because this option achieved the highest concentrations of ethanol after fermentation. Further studies, using methods similar to ones employed here, can help understand and improve the performance and hence the economics of integrated processes involving enzymes and fermentative microorganisms. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2010 [source] Detecting Tropical Forests' Responses to Global Climatic and Atmospheric Change: Current Challenges and a Way ForwardBIOTROPICA, Issue 1 2007Deborah A. ClarkArticle first published online: 21 DEC 200 ABSTRACT Because of tropical forests' disproportionate importance for world biodiversity and for the global carbon cycle, we urgently need to understand any effects on these ecosystems from the ongoing changes in climate and atmosphere. This review, intended to complement existing data reviews on this topic, focuses on three major classes of challenges that we currently face when trying to detect and interpret directional changes in tropical forests. One is the very limited existing information on the historical context of study sites. Lasting effects from past climate, natural disturbances, and/or human activities could be significantly affecting current-day processes in tropical forests and need to be investigated for all active field sites. Second, while progress has been made in recent years on standardizing and refining research approaches, a number of methods- and data-limitations continue to affect efforts both to detect within-forest changes and to relate them to ongoing environmental change. Important outstanding needs are improved sampling designs, longer time-series of observations, filling key data gaps, and data access. Finally, forest responses to ongoing environmental change are complex. The effects of many simultaneously changing environmental factors are integrated by the plants, and their responses can involve significant lags, carryovers, and non-linearities. Specifying effects of individual environmental changes, however, is required for accurate ecosystem-process models and thus for projecting future impacts on these forests. After discussing these several types of challenges and ways to address them, I conclude with a priority agenda for this critical area of research. Abstract in Spanish is available at http://www.blackwell-synergy.com/loi/btp. RESUMEN Debido a la importancia desproporcionada de los bosques tropicales para la biodiversidad mundial y para el ciclo global del carbono, es urgente identificar los impactos sobre estos ecosistemas provocados por los cambios actuales en el clima y en la atmósfera. Este artículo de revisión, escrito con el propósito de complementar otras revisiones recientes, se enfoca en tres principales clases de retos que enfrentamos actualmente en la detección e interpretación de cambios direccionales en los bosques tropicales. Primero es la gran escasez de información histórica acerca de los sitios de estudio. Los procesos actuales en los bosques tropicales pueden reflejar los efectos prolongados del pasado climático, las perturbaciones naturales y/o las actividades humanas, por lo que deben de ser investigados en todos los sitios actuales de estudio. Segundo, a pesar de avances recientes en la estandarización y el refinamiento de los métodos de investigación, nuestra habilidad para detectar cambios en los bosques y ligarlos a los grandes cambios ambientales sigue siendo limitada. Para garantizar avances en el área se requiere mejorar los diseños de muestreo, extender las series de observación en el tiempo a plazos mayores, llenar ciertos vacíos claves en el conocimiento, y facilitar el acceso a los datos existentes. Por último, se requiere de enfoques que tomen en cuenta la complejidad de las respuestas de los bosques a los cambios ambientales. Las plantas integran los efectos de cambios simultáneos en múltiples factores ambientales, y sus respuestas pueden ser no lineales e incluir efectos de retraso y acarreo. No obstante, es importante también especificar los efectos individuales de los diferentes cambios ambientales para afinar los modelos de procesos a nivel del ecosistema, y así poder proyectar los impactos futuros sobre estos bosques. Después de discutir dichos retos y estrategias para enfrentarlos, concluyo con una agenda de prioridades para esta área crítica de investigación. [source] Comparisons of U.S. Government Communication Practices: Expanding the Government Communication Decision WheelCOMMUNICATION THEORY, Issue 3 2010J. Suzanne Horsley Government communication is pervasive and has an impact on every aspect of American public life. However, there is minimal theory-driven research in this critical area of communication. This research explores comparisons of communication practices and the status of professional development among the four levels of U.S. government organizations through a survey of 781 government communicators. The study identifies six significant differences and two similarities in how the public sector environment affects communication practices at the city, county, state, and federal levels. The findings were applied to a modification of the government communication decision wheel, a model that offers a theoretical foundation for the study of government communication within its unique environmental context free from the bias of corporate-centric research assumptions. The findings contribute to communication theory development for the underresearched public sector. Comparaisons des pratiques de communication du gouvernement américain : pour développer la roue des décisions communicationnelles du gouvernement J. Suzanne Horsley, Brooke Fisher Liu, & Abbey Blake Levenshus La communication gouvernementale est omniprésente et affecte tous les aspects de la vie publique américaine. Néanmoins, il existe très peu de recherches guidées par la théorie dans ce domaine critique de la communication. Cette recherche explore des comparaisons dans les pratiques communicationnelles et le développement professionnel auprès de quatre niveaux gouvernementaux américains, par une enquête menée auprès de 781 agents de communication du gouvernement. L'étude identifie cinq différences importantes et trois similarités dans les façons par lesquelles le milieu du secteur public influence les pratiques de communication aux niveaux de la municipalité, du comté, de l'État et du pays. Les résultats ont été appliqués de façon à modifier la roue des décisions communicationnelles du gouvernement, un fondement théorique pour l'étude de la communication gouvernementale dans son milieu unique, sans les biais des hypothèses de recherche axées sur le secteur privé. Les résultats contribuent au développement des théories en communication à propos du secteur public, toujours sous-étudié. Vergleiche von Kommunikationspraktiken der US-Regierung: Eine Erweiterung des Kommunikationsentscheidungsrads der Regierung J. Suzanne Horsley, Brooke Fisher Liu, & Abbey Blake Levenshus Die Kommunikation der Regierung ist allgegenwärtig und berührt jeden Aspekt des Lebens der amerikanischen Öffentlichkeit. Dennoch gibt es wenig theoriebasierte Forschung in diesem zentralen Feld der Kommunikation. Diese Studie betrachtet Vergleiche der Kommunikationspraktiken und professionellen Entwicklung auf vier Ebenen der US-Regierung mittels einer Umfrage unter 781 Regierungskommunikatoren. Die Studie identifiziert fünf signifikante Unterschiede und drei ähnliche Aspekte, wie der öffentliche Sektor die Kommunikationspraktiken auf Stadt-, Landkreis-, Länder- und Bundesebene beeinflusst. Die Ergebnisse wurden zur Modifikation des Kommunikationsentscheidungsrads der Regierung herangezogen - eine theoretische Basis für die Untersuchung von Regierungskommunikation innerhalb ihres einzigartigen Kontextes und frei von Befangenheiten unternehmenszentristischer Forschungsannahmen. Die Ergebnisse tragen zur Entwicklung von Kommunikationstheorie im bislang unterbeleuchteten öffentlichen Sektor bei. Las Comparaciones de las Prácticas de Comunicación del Gobierno de los EE.UU.: Expandiendo la Comunicación de la Rueda de Decisión del Gobierno J. Suzanne Horsley, Brooke Fisher Liu, & Abbey Blake Levenshus Advertising and Public Relations, University of Alabama, 255 S Central Campus Dr., Room 2400, Salt Lake City, UT 84112, USA Resumen La comunicación del gobierno es dominante y toca cada aspecto de la vida pública Americana. No obstante, hay un mínimo de investigación dirigida por la teoría sobre esta área de comunicación crítica. Esta investigación explora las comparaciones de las prácticas de comunicación y el desarrollo profesional entre 4 niveles del gobierno de los EE.UU. mediante una encuesta de 781 comunicadores del gobierno. Este estudio identifica 5 diferencias significativas y 3 similitudes en cómo el sector público del medio ambiente afecta las prácticas de comunicación al nivel de la ciudad, el condado, el estado y el estado federal. Estos hallazgos fueron aplicados a modificación de la comunicación de la rueda de decisión del gobierno, una fundación teórica para el estudio de la comunicación del gobierno dentro de este contexto único del medio ambiente libre de las preconcepciones de las asunciones de la investigación centradas en las corporaciones. Los hallazgos contribuyen al desarrollo de la teoría de la comunicación para el sector público poco investigado. [source] A Freshwater Classification Approach for Biodiversity Conservation PlanningCONSERVATION BIOLOGY, Issue 2 2005JONATHAN V. HIGGINS biodiversidad de agua dulce; clasificación; planificación de conservación; representativo Abstract:,Freshwater biodiversity is highly endangered and faces increasing threats worldwide. To be complete, regional plans that identify critical areas for conservation must capture representative components of freshwater biodiversity as well as rare and endangered species. We present a spatially hierarchical approach to classify freshwater systems to create a coarse filter to capture representative freshwater biodiversity in regional conservation plans. The classification framework has four levels that we described using abiotic factors within a zoogeographic context and mapped in a geographic information system. Methods to classify and map units are flexible and can be automated where high-quality spatial data exist, or can be manually developed where such data are not available. Products include a spatially comprehensive inventory of mapped and classified units that can be used remotely to characterize regional patterns of aquatic ecosystems. We provide examples of classification procedures in data-rich and data-poor regions from the Columbia River Basin in the Pacific Northwest of North America and the upper Paraguay River in central South America. The approach, which has been applied in North, Central, and South America, provides a relatively rapid and pragmatic way to account for representative freshwater biodiversity at scales appropriate to regional assessments. Resumen:,La biodiversidad de agua dulce está en peligro y enfrenta amenazas crecientes en todo el mundo. Para ser completos, los planes regionales que identifican áreas críticas para la conservación deben incluir componentes representativos de la biodiversidad de agua dulce así como especies raras y en peligro. Presentamos un método espacialmente jerárquico para clasificar sistemas de agua dulce para crear un filtro grueso que capte a la biodiversidad de agua dulce en los planes regionales de conservación. La estructura de la clasificación tiene cuatro niveles que describimos utilizando factores abióticos en un contexto zoogeográfico y localizamos en un sistema de información geográfico. Los métodos para clasificar y trazar mapas son flexibles y pueden ser automatizados, donde existen datos espaciales de alta calidad, o desarrollados manualmente cuando tales datos no están disponibles. Los productos incluyen un inventario completo de unidades mapeadas y clasificadas que pueden ser usadas remotamente para caracterizar patrones regionales de ecosistemas acuáticos. Proporcionamos ejemplos de procedimientos de clasificación en regiones ricas y pobres en datos en la cuenca del Río Columbia en el noroeste de Norte América y del Río Paraguay en Sudamérica central. El método, que ha sido aplicado en Norte, Centro y Sudamérica, proporciona una forma relativamente rápida y pragmática de contabilizar biodiversidad de agua dulce representativa en escalas adecuadas para evaluaciones regionales. [source] Research Priorities for Surge CapacityACADEMIC EMERGENCY MEDICINE, Issue 11 2006Richard E. Rothman MD The 2006 Academic Emergency Medicine Consensus Conference discussed key concepts within the field of surge capacity. Within the breakout session on research priorities, experts in disaster medicine and other related fields used a structured nominal-group process to delineate five critical areas of research. Of the 14 potential areas of discovery identified by the group, the top five were the following: 1) defining criteria and methods for decision making regarding allocation of scarce resources, 2) determining effective triage protocols, 3) determining key decision makers for surge-capacity planning and means to evaluate response efficacy (e.g., incident command), 4) developing effective communication and information-sharing strategies (situational awareness) for public-health decision support, and 5) developing methods and evaluations for meeting workforce needs. Five working groups were formed to consider the above areas and to devise sample research questions that were refined further by the entire group of participants. [source] Importance of changing CO2, temperature, precipitation, and ozone on carbon and water cycles of an upland-oak forest: incorporating experimental results into model simulationsGLOBAL CHANGE BIOLOGY, Issue 9 2005Paul J. Hanson Abstract Observed responses of upland-oak vegetation of the eastern deciduous hardwood forest to changing CO2, temperature, precipitation and tropospheric ozone (O3) were derived from field studies and interpreted with a stand-level model for an 11-year range of environmental variation upon which scenarios of future environmental change were imposed. Scenarios for the year 2100 included elevated [CO2] and [O3] (+385 ppm and +20 ppb, respectively), warming (+4°C), and increased winter precipitation (+20% November,March). Simulations were run with and without adjustments for experimentally observed physiological and biomass adjustments. Initial simplistic model runs for single-factor changes in CO2 and temperature predicted substantial increases (+191% or 508 g C m,2 yr,1) or decreases (,206% or ,549 g C m,2 yr,1), respectively, in mean annual net ecosystem carbon exchange (NEEa,266±23 g C m,2 yr,1 from 1993 to 2003). Conversely, single-factor changes in precipitation or O3 had comparatively small effects on NEEa (0% and ,35%, respectively). The combined influence of all four environmental changes yielded a 29% reduction in mean annual NEEa. These results suggested that future CO2 -induced enhancements of gross photosynthesis would be largely offset by temperature-induced increases in respiration, exacerbation of water deficits, and O3 -induced reductions in photosynthesis. However, when experimentally observed physiological adjustments were included in the simulations (e.g. acclimation of leaf respiration to warming), the combined influence of the year 2100 scenario resulted in a 20% increase in NEEa not a decrease. Consistent with the annual model's predictions, simulations with a forest succession model run for gradually changing conditions from 2000 to 2100 indicated an 11% increase in stand wood biomass in the future compared with current conditions. These model-based analyses identify critical areas of uncertainty for multivariate predictions of future ecosystem response, and underscore the importance of long term field experiments for the evaluation of acclimation and growth under complex environmental scenarios. [source] Assessment, intervention, and research with infants in out-of-home placementINFANT MENTAL HEALTH JOURNAL, Issue 5 2002Robert B. Clyman Infants constitute a large and increasing proportion of youth in out-of-home placement. These infants have very high rates of medical illnesses, developmental delays, and substantial risks for psychopathology. They receive varying amounts of services from a complex and poorly integrated service system that includes four principal service sectors: the child welfare, medical, early intervention, and mental health service sectors. These service systems are currently undergoing major changes in their policies, organization, and financing, such as the introduction of managed care into the child welfare system. In this article, we provide an overview of what is known about infants in out-of-home placement. We then summarize approaches to infant mental health assessment and intervention from a comprehensive perspective that addresses the infants' multiple problems and acknowledges that they need to receive services from multiple systems that are undergoing rapid change. We conclude by highlighting a number of critical areas in need of research. ©2002 Michigan Association for Infant Mental Health. [source] Subclinical reactivation of herpes simplex virus type 1 in the oral cavityMOLECULAR ORAL MICROBIOLOGY, Issue 5 2000B. Knaup Reactivation in the oral cavity either symptomatically (recrudescence) or without symptoms (recurrence) may contribute to the transmission of herpes simplex virus type 1 (HSV-1), especially in critical areas of exposure such as dentistry. In order to measure the frequency of HSV-1 reactivation, nested polymerase chain reaction (PCR) was performed on oral swabs collected from 30 healthy people over a period of 58,161 days. In total 19 of 25 (76%) seropositive people were PCR-positive at least once, 6 of these 19 (32%) had recrudescence and 13 (68%) had only asymptomatic reactivation. Frequencies of additional recurrences were higher in people showing symptomatic reactivation than in those who had only recurrences. Recrudescence is a risk factor for elevated levels of asymptomatic HSV-shedding. In most cases HSV-1 was detected only by nested PCR investigated by early onset of therapy or time span before sampling. [source] Adjunct faculty and the continuing quest for qualityNEW DIRECTIONS FOR COMMUNITY COLLEGES, Issue 140 2007Donald W. Green This chapter addresses the use of adjunct faculty in community colleges. It examines issues of finding, hiring, orienting, evaluating, and developing adjuncts and stresses critical areas of ensuring quality and maintaining institutional standards. [source] Collective bargaining and community collegesNEW DIRECTIONS FOR COMMUNITY COLLEGES, Issue 125 2004Richard J. Boris This chapter reviews the three-decade history of collective bargaining at community colleges and analyzes how collective bargaining has altered critical areas in the life of community colleges. [source] Complaint handling in pharmaceutical companiesQUALITY ASSURANCE JOURNAL, Issue 1 2007Glaucia Karime Braga Abstract Complaints show customer dissatisfaction about the quality of a pharmaceutical product. Despite a regulatory obligation in several countries, a good complaint handling system gives the company an opportunity to improve the quality of their products, being a good tool for the maintenance of Good Manufacturing Practices and a way to establish a committed relationship with their customers. A systematic procedure must be developed and implemented in order to register and investigate each complaint received and not only the Quality Assurance area must be involved. This process must involve other critical areas such as Marketing, Production, Quality Control, Finance, Regulatory and Legal Affairs. Thus the aim of this article is to discuss the main steps of a good complaint handling procedure that can be readily implemented in pharmaceutical companies. Copyright © 2007 John Wiley & Sons, Ltd. [source] Company Competencies as a Network: The Role of Product DevelopmentTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 3 2000Hanne Harmsen Product development managers and academics like to assure themselves and each other that new product development is one of the most critical areas of company competence and contributes positively to company success. But does top management agree? Because if they do not, the consequences will heavily influence the resource allocation to product development and career possibilities of new product developments manager. This study examines how top managers view the importance of product development relative to other central competence areas. Although asking managers about their perception is one way of evaluating the importance, its contribution to company success is another important measure. In this study, the impact of product development, relative to other important competence areas, is measured to assess further how critical product development is for overall company success. The authors investigate these matters in a survey of top managers in 513 Danish production companies. Ten areas important for achieving company objectives are identified. These are product development, market intelligence, production management, strategy and vision, sales, market responsiveness, promotion, internal co-operation, image, and supply management. Product development is rated a fairly important competence as it ranks number four, with sales, market responsiveness, and production management ranking numbers one to three. Yet a distressing negative impact on overall company success is found for product development proficiency, whereas success is positively related to production management, image, and differentiation of products. Further analysis reveals that product development contributes positively to success by enabling product differentiation and enhancing promotion proficiency. Influenced by and influencing many other competencies, product development is found to be a central competence. Results support a nonfunctional and broad perspective of how bundles of competences interact and impact on success and establish a positive overall contribution to product development. [source] Birds as tourism flagship species: a case study of tropical islandsANIMAL CONSERVATION, Issue 6 2009D. Veríssimo Abstract Species selected as flagships to promote conservation activities around the world are typically well known and charismatic mega-fauna. Unfortunately this limits the scope for applying the concept as some critical areas for biodiversity conservation, such as tropical islands, lack such species. In this study, we explore the potential to apply the concept of ,tourism flagship species' to tropical island birds of the Seychelles, an archipelago of considerable importance for conservation that is highly dependent on international tourism. In particular we wish to identify which species attributes are most influential with regard to their potential for fundraising among international tourists. Using a choice experiment approach and using state-of-the-art econometric methods, we found that conservation attributes and physical appearance of the bird species are both important in terms of raising funds for conservation. Nevertheless, conservation attributes ranked higher in the respondents preferences. Our results suggest that there is considerable potential for a variety of species to effectively act as flagships in developing nations that are dependent on international tourism and rich in biodiversity but lack charismatic fauna. [source] Improvement on the Auxiliary Total Artificial Heart (ATAH) Left Chamber Design,ARTIFICIAL ORGANS, Issue 5 2003Aron Andrade Abstract: The auxiliary total artificial heart (ATAH) is an electromechanically driven artificial heart with reduced dimensions, which is able to be implanted in the right thoracic or abdominal cavities of an average human patient without removing the natural heart or the heart neurohumoral inherent control mechanism for the arterial pressure. This device uses a brushless direct current motor and a mechanical actuator (roller screw) to move two diaphragms. The ATAH's beating frequency is regulated through the change of the left preload, based on Frank-Starling's law, assisting the native heart in obtaining adequate blood flow. The ATAH left and right stroke volumes are 38 ml and 34 ml, respectively, giving approximately 5 L/min of cardiac output at 160 bpm. Flow visualization studies were performed in critical areas on the ATAH left chamber. A closed circuit loop was used with water and glycerin (37%) at 25°C. Amberlite particles (80 mesh) were illuminated by a 1 mm planar helium-neon laser light. With left mean preload fixed at 10 mm Hg and the afterload at 100 mm Hg, the heart rate varied from 60 to 200 bpm. Two porcine valves were used on the inlet and outlet ports. The flow pattern images were obtained using a color micro-camera and a video recorder. Subsequently, these images were digitized using a PC computer. A persistent stagnant flow was detected in the left chamber inlet port. After improvement on the left chamber design, this stagnant flow disappeared. [source] Erosion models: quality of spatial predictionsHYDROLOGICAL PROCESSES, Issue 5 2003Victor Jetten Abstract An Erratum has been published for this article in Hydrological Processes 18(3) 2004, 595. An overview is given on the predictive quality of spatially distributed runoff and erosion models. A summary is given of the results of model comparison workshops organized by the Global Change and Terrestrial Ecosystems Focus 3 programme, as well as other results obtained by individual researchers. The results concur with the generally held viewpoint in the literature that the predictive quality of distributed models is moderately good for total discharge at the outlet, and not very good for net soil loss. This is only true if extensive calibration is done: uncalibrated results are generally bad. The more simple lumped models seem to perform equally well as the more complex distributed models, although the latter produce more detailed spatially distributed results that can aid the researcher. All these results are outlet based: models are tested on lumped discharge and soil loss or on hydrographs and sedigraphs. Surprisingly few tests have been done on the comparison of simulated and modelled erosion patterns, although this may arguably be just as important in the sense of designing anti-erosion measures and determining source and sink areas. Two studies are shown in which the spatial performance of the erosion model LISEM (Limburg soil erosion model) is analysed. It seems that: (i) the model is very sensitive to the resolution (grid cell size); (ii) the spatial pattern prediction is not very good; (iii) the performance becomes better when the results are resampled to a lower resolution and (iv) the results are improved when certain processes in the model (in this case gully incision) are restricted to so called ,critical areas', selected from the digital elevation model with simple rules. The difficulties associated with calibrating and validating spatially distributed soil erosion models are, to a large extent, due to the large spatial and temporal variability of soil erosion phenomena and the uncertainty associated with the input parameter values used in models to predict these processes. They will, therefore, not be solved by constructing even more complete, and therefore more complex, models. However, the situation may be improved by using more spatial information for model calibration and validation rather than output data only and by using ,optimal' models, describing only the dominant processes operating in a given landscape. Copyright © 2003 John Wiley & Sons, Ltd. [source] | |||||||||||||||||||