Home About us Contact
|
Home About us Contact | ||
|
|
||
Biases
Kinds of Biases Selected AbstractsTeaching Culturally Appropriate Care: A Review of Educational Models and MethodsACADEMIC EMERGENCY MEDICINE, Issue 12 2006Cherri Hobgood MD Abstract The disparities in health care and health outcomes between the majority population and cultural and racial minorities in the United States are a problem that likely is influenced by the lack of culturally competent care. Emergency medicine and other primary-care specialties remain on the front lines of this struggle because of the nature of their open-door practice. To provide culturally appropriate care, health care providers must recognize the factors impeding cultural awareness, seek to understand the biases and traditions in medical education potentially fueling this phenomenon, and create a health care community that is open to individuals' otherness, thus leading to better communication of ideas and information between patients and their health care providers. This article highlights the rationale for and current problems in teaching cultural competency and examines several different models implemented to teach and promote cultural competency along the continuum of emergency medicine learners. However, the literature addressing the true efficacy of such programs in leading to long-lasting change and improvement in minority patients' clinical outcomes remains insufficient. [source] The Need to Rationalize and Prioritize Threatening Processes Used to Determine Threat Status in the IUCN Red ListCONSERVATION BIOLOGY, Issue 6 2009MATT W. HAYWARD carnivora; competencia; estatus de conservación; procesos amenazantes Abstract:,Thorough evaluation has made the International Union for Conservation of Nature (IUCN) Red List the most widely used and accepted authority on the conservation status of biodiversity. Although the system used to determine risk of extinction is rigorously and objectively applied, the list of threatening processes affecting a species is far more subjectively determined and has not had adequate review. I reviewed the threats listed in the IUCN Red List for randomly selected groups within the three most threatened orders of mammals: Artiodactyla, Carnivora, and Primates. These groups are taxonomically related and often ecologically similar, so I expected they would suffer relatively similar threats. Hominoid primates and all other terrestrial fauna faced similar threats, except for bovine artiodactyls and large, predatory carnivores, which faced significantly different threats. Although the status of bovines and hominoids and the number of threats affecting them were correlated, this was not the case for large carnivores. Most notable, however, was the great variation in the threats affecting individual members of each group. For example, the endangered European bison (Bison bonasus) has no threatening processes listed for it, and the lion (Panthera leo) is the only large predator listed as threatened with extinction by civil war. Some threatening processes appear spurious for the conservation of the species, whereas other seemingly important factors are not recorded as threats. The subjective nature of listing threatening processes, via expert opinion, results in substantial biases that may be allayed by independent peer review, use of technical manuals, consensus among multiple assessors, incorporation of probability modeling via decision-tree analysis, and adequate coordination among evaluators. The primary focus should be on species-level threats rather than population-level threats because the IUCN Red List is a global assessment and smaller-scale threats are more appropriate for national status assessments. Until conservationists agree on the threats affecting species and their relative importance, conservation action and success will be hampered by scattering scarce resources too widely and often by implementing conflicting strategies. Resumen:,La evaluación exhaustiva ha hecho que la Lista Roja de la Unión Internacional para la Conservación de la Naturaleza (UICN) sea la autoridad más aceptada y ampliamente utilizada respecto al estatus de conservación de la biodiversidad. Aunque el sistema utilizado para determinar el riesgo de extinción es aplicado rigurosa y objetivamente, la lista de procesos amenazantes que afectan a las especies es determinado muy subjetivamente y no es revisado adecuadamente. Revisé las amenazas consideradas en la Lista Roja UICN para grupos seleccionados aleatoriamente en los tres órdenes de mamíferos más amenazados: Artyodactila, Carnivora y Primates. Estos grupos están relacionados taxonómicamente y a menudo son ecológicamente similares, así que esperaba que tuvieran amenazas relativamente similares. Los primates homínidos y toda la demás fauna terrestre enfrentan amenazas similares, excepto por los bovinos artiodáctilos y los carnívoros depredadores mayores, que enfrentan amenazas significativamente diferentes. Aunque el estatus de los bovinos y homínidos y el número de amenazas que los afectan estuvieron correlacionados, este no fue el caso para los carnívoros mayores. Sin embargo, lo más notable fue la gran variación en las amenazas que afectan a miembros individuales de cada grupo. Por ejemplo, no hay procesos amenazantes enlistados para el bisonte europeo (Bison bonasus), y el león (Panthera leo) es el único depredador mayor enlistado como amenazado de extinción por la guerra civil. Algunos procesos amenazantes parecen espurios para la conservación de las especies, mientras que otros factores aparentemente importantes no están registrados como amenazas. La naturaleza subjetiva de los procesos de enlistado, por medio de la opinión de expertos, resulta en sesgos sustanciales que pueden disiparse por la revisión independiente por pares, el uso de manuales técnicos, el consenso de múltiples asesores, la incorporación del modelado probabilístico mediante análisis de árboles de decisión y la adecuada coordinación entre evaluadores. El enfoque principal debería ser sobre amenazas a nivel de especies en lugar de amenazas a nivel de poblaciones porque la Lista Roja UICN es una evaluación global y las amenazas a menor escala son más apropiadas para evaluaciones nacionales de estatus. Hasta que los conservacionistas estén de acuerdo sobre las amenazas que afectan a las especies y su importancia relativa, las acciones de conservación y su éxito estarán obstaculizados por la dispersión demasiado amplia de recursos limitados y a menudo por la implementación de estrategias contrapuestas. [source] Expanding the Global Network of Protected Areas to Save the Imperiled Mediterranean BiomeCONSERVATION BIOLOGY, Issue 1 2009EMMA C. UNDERWOOD análisis de disparidad; áreas protegidas; biodiversidad; ecosistemas Mediterráneos; pérdida de hábitat Abstract:,Global goals established by the Convention on Biological Diversity stipulate that 10% of the world's ecological regions must be effectively conserved by 2010. To meet that goal for the mediterranean biome, at least 5% more land must be formally protected over the next few years. Although global assessments identify the mediterranean biome as a priority, without biologically meaningful analysis units, finer-resolution data, and corresponding prioritization analysis, future conservation investments could lead to more area being protected without increasing the representation of unique mediterranean ecosystems. We used standardized analysis units and six potential natural vegetation types stratified by 3 elevation zones in a global gap analysis that systematically explored conservation priorities across the mediterranean biome. The highest levels of protection were in Australia, South Africa, and California-Baja California (from 9,11%), and the lowest levels of protection were in Chile and the mediterranean Basin (<1%). Protection was skewed to montane elevations in three out of five regions. Across the biome only one of the six vegetation types,mediterranean shrubland,exceeded 10% protection. The remaining vegetation types,grassland, scrub, succulent dominated, woodland, and forest,each had <3% protection. To guard against biases in future protection efforts and ensure the protection of species characteristic of the mediterranean biome, we identified biodiversity assemblages with <10% protection and subject to >30% conversion and suggest that these assemblages be elevated to high-priority status in future conservation efforts. Resumen:,Las metas globales establecidas por la Convención sobre Diversidad Biológica estipulan que 10% de las regiones ecológicas del mundo deberán estar conservadas efectivamente en 2010. Para alcanzar esa meta en el bioma mediterráneo, por lo menos 5% más de superficie debe estar protegida formalmente en los próximos años. Aunque las evaluaciones globales identifican al bioma mediterráneo como una prioridad, sin unidades de análisis biológicamente significativas, datos de resolución más fina y los correspondientes análisis de priorización, las inversiones futuras en conservación pudieran conducir a la protección de más superficie sin incrementar la representación de los ecosistemas mediterráneos únicos. Utilizamos unidades de análisis estandarizadas y seis tipos potenciales de vegetación natural estratificados en tres zonas de elevación en un análisis global de disparidad que exploró sistemáticamente las prioridades de conservación en el bioma mediterráneo. Los niveles de protección más altos se localizaron en Australia, África del Sur y California-Baja California (de 9,11%) y los niveles de protección más bajos se localizaron en Chile y la Cuenca del mediterráneo (<1%). La protección estaba sesgada hacia elevaciones altas en tres de las cinco regiones. En todo el bioma, solo uno de los seis tipos de vegetación,matorral mediterráneo,excedió 10% de protección. Los tipos de vegetación restantes,pastizal, matorral, dominio de suculentas, y bosques,tenían <3% de protección cada uno. Para evitar sesgos en futuros esfuerzos de protección y asegurar la protección de especies características del bioma mediterráneo, identificamos ensambles de biodiversidad con <10% de protección y sujetos a >30% de conversión y sugerimos que estos ensambles sean elevados a un estatus de alta prioridad en esfuerzos de conservación en el futuro. [source] Potential Errors in Detecting Earnings Management: Reexamining Studies Investigating the AMT of 1986,CONTEMPORARY ACCOUNTING RESEARCH, Issue 4 2001Won W. Choi Abstract In this paper we seek to document errors that could affect studies of earnings management. The book income adjustment (BIA) of the alternative minimum tax (AMT) created apparently strong incentives to manage book income downward in 1987. Five earlier papers using different methodologies and samples all conclude that earnings were reduced in response to the BIA. This consensus of findings offers an opportunity to investigate our speculation that methodological biases are more likely when there appear to be clear incentives for earnings management. A reexamination of these studies uncovers potential biases related to a variety of factors, including choices of scaling variables, selection of affected and control samples, and measurement error in estimated discretionary accruals. A reexamination of the argument underlying these studies also suggests that the incentives to manage earnings are less powerful than initially predicted, and are partially mitigated by tax and non-tax factors. As a result, we believe that the extent of earnings management that occurred in 1987 in response to the BIA remains an unresolved issue. [source] Behavioural Biases of Japanese Institutional Investors: fund management and corporate governanceCORPORATE GOVERNANCE, Issue 4 2005Megumi Suto This study examines the behavioural biases of Japanese institutional investors and discusses implications for their role in corporate governance, based on the findings of a questionnaire survey of fund managers carried out in 2003. Statistical analysis of the survey results reveals a short-term bias in fund managers' investment time horizons, herding and self-marketing to improve the appearance of portfolio performance under the pressure either of customers or of institutional restraints. We conclude that institutional investors' behaviour contradicts their role as shareholders. [source] Escalation: The Role of Problem Recognition and Cognitive BiasDECISION SCIENCES, Issue 3 2007Mark Keil ABSTRACT Escalation of commitment to a failing course of action is an enduring problem that remains central to the study of managerial behavior. Prior research suggests that escalation behavior results when decision makers choose to ignore negative feedback concerning the viability of a previously chosen course of action. Previous work has also suggested that certain cognitive biases might promote escalation behavior, but there has been little attempt to explore how biases other than framing affect escalation. In this article, we explore the extent to which decision makers actually perceive negative feedback as indicative of a problem and how this influences their decision to escalate. Although problem recognition and cognitive biases have been intensively studied individually, little is known about their effect on escalation behavior. In this research, we construct and test an escalation decision model that incorporates both problem recognition and two cognitive biases: selective perception and illusion of control. Our results revealed a significant inverse relationship between problem recognition and escalation. Furthermore, selective perception and illusion of control were found to significantly affect both problem recognition and escalation. The implications of these findings for research and practice are discussed. To improve problem recognition and reduce the incidence of escalation, practicing managers should implement modern project management practices that can help to identify and highlight potential problems while guarding against these two key cognitive biases that promote the behavior. [source] Selective attention in anxiety: Distraction and enhancement in visual searchDEPRESSION AND ANXIETY, Issue 1 2003Mike Rinck Abstract According to cognitive models of anxiety, anxiety patients exhibit an attentional bias towards threat, manifested as greater distractibility by threat stimuli and enhanced detection of them. Both phenomena were studied in two experiments, using a modified visual search task, in which participants were asked to find single target words (GAD-related, speech-related, neutral, or positive) hidden in matrices made up of distractor words (also GAD-related, speech-related, neutral, or positive). Generalized anxiety disorder (GAD) patients, social phobia (SP) patients afraid of giving speeches, and healthy controls participated in the visual search task. GAD patients were slowed by GAD-related distractor words but did not show statistically reliable evidence of enhanced detection of GAD-related target words. SP patients showed neither distraction nor enhancement effects. These results extend previous findings of attentional biases observed with other experimental paradigms. Depression and Anxiety 18:18,28, 2003. © 2003 Wiley-Liss, Inc. [source] Gender, Traditional Authority, and the Politics of Rural Reform in South AfricaDEVELOPMENT AND CHANGE, Issue 4 2002Haripriya Rangan The new South African Constitution, together with later policies and legislation, affirm a commitment to gender rights that is incompatible with the formal recognition afforded to unelected traditional authorities. This contradiction is particularly evident in the case of land reform in many rural areas, where women's right of access to land is denied through the practice of customary law. This article illustrates the ways in which these constitutional contradictions play out with particular intensity in the ,former homelands' through the example of a conflict over land use in Buffelspruit, Mpumalanga province. There, a number of women who had been granted informal access to communal land for the purposes of subsistence cultivation had their rights revoked by the traditional authority. Despite desperate protests, they continue to be marginalized in terms of access to land, while their male counterparts appropriate communal land for commercial farming and cattle grazing. Drawing on this protest, we argue that current South African practice in relation to the pressing issue of gender equity in land reform represents a politics of accommodation and evasion that tends to reinforce gender biases in rural development, and in so doing, undermines the prospects for genuinely radical transformation of the instituted geographies and institutionalized practices bequeathed by the apartheid regime. [source] The evolutionary psychology of left and right: Costs and benefits of lateralizationDEVELOPMENTAL PSYCHOBIOLOGY, Issue 6 2006Giorgio VallortigaraArticle first published online: 2 AUG 200 Abstract Why do the left and right sides of the vertebrate brain play different functions? Having a lateralized brain, in which each hemisphere carries out different functions, is ubiquitous among vertebrates. The different specialization of the left and right side of the brain may increase brain efficiency,and some evidence for that is reported here. However, lateral biases due to brain lateralization (such as preferences in the use of a limb or, in animals with laterally placed eyes, of a visual hemifield) usually occur at the population level, with most individuals showing similar direction of bias. Individual brain efficiency does not require the alignment of lateralization in the population. Why then are not left- and right-type individuals equally common? Not only humans, but most vertebrates show a similar pattern. For instance, in the paper I report evidence that most toads, chickens, and fish react faster when a predator approaches from the left. I argue that invoking individual brain efficiency (lateralization may increase fitness), evolutionary chance or direct genetic mechanisms cannot explain this widespread pattern. Instead, using concepts from mathematical theory of games, I show that alignment of lateralization at the population level may arise as an "evolutionarily stable strategy" when individually asymmetrical organisms must coordinate their behavior with that of other asymmetrical organisms. Thus, the population structure of lateralization may result from genes specifying the direction of asymmetries which have been selected under "social" pressures. © 2006 Wiley Periodicals, Inc. Dev Psychobiol 48: 418,427, 2006. [source] Cross-species investigations of prenatal experience, hatching behavior, and postnatal behavioral lateralityDEVELOPMENTAL PSYCHOBIOLOGY, Issue 2 2001Michael Bernard Casey Abstract Turning biases have been reported in some mammalian species, but less is known about such biases in nonmammalians. This study investigated turning biases in domestic chicks, bobwhite and Japanese quail, leopard geckos, and snapping turtles. Domestic chicks (white leghorn and bantam) and bobwhite quail demonstrate strong group laterality. Japanese quail chicks, snapping turtles, and leopard geckos demonstrate no significant group bias. Results are discussed with regard to differences in embryonic experience, hatching behavior, and postnatal environment. © 2001 John Wiley & Sons, Inc. Dev Psychobiol 39: 84,91, 2001 [source] Generality with specificity: the dynamic field theory generalizes across tasks and time scalesDEVELOPMENTAL SCIENCE, Issue 4 2008Vanessa R. Simmering A central goal in cognitive and developmental science is to develop models of behavior that can generalize across both tasks and development while maintaining a commitment to detailed behavioral prediction. This paper presents tests of one such model, the Dynamic Field Theory (DFT). The DFT was originally proposed to capture delay-dependent biases in spatial recall and developmental changes in spatial recall performance. More recently, the theory was generalized to adults' performance in a second spatial working memory task, position discrimination. Here we use the theory to predict a specific, complex developmental pattern in position discrimination. Data with 3- to 6-year-old children and adults confirm these predictions, demonstrating that the DFT achieves generality across tasks and time scales, as well as the specificity necessary to generate novel, falsifiable predictions. [source] Enhanced perceptual processing of speech in autismDEVELOPMENTAL SCIENCE, Issue 1 2008Anna Järvinen-Pasley Theories of autism have proposed that a bias towards low-level perceptual information, or a featural/surface-biased information-processing style, may compromise higher-level language processing in such individuals. Two experiments, utilizing linguistic stimuli with competing low-level/perceptual and high-level/semantic information, tested processing biases in children with autism and matched controls. Whereas children with autism exhibited superior perceptual processing of speech relative to controls, and showed no evidence of either a perceptual or semantic processing bias, controls showed a tendency to process speech semantically. The data provide partial support to the perceptual theories of autism. It is additionally proposed that the pattern of results may reflect different patterns of attentional focusing towards single or multiple stimulus cues in speech between children with autism and controls. [source] Biased to learn languageDEVELOPMENTAL SCIENCE, Issue 6 2007Núria Sebastián-Gallés Some recent publications that explore the foundations of early language development are reviewed in this article. The review adopts the pivotal idea that infants' advancements are helped by the existence of different types of biases. The infant's discovery of the phonological properties of the language of the environment, as well as their learning of words, is assisted by different types of processing biases, ranging from perceptual to social factors. [source] Hemispheric asymmetries in children's perception of nonlinguistic human affective soundsDEVELOPMENTAL SCIENCE, Issue 1 2004Seth D. Pollak In the present work, we developed a database of nonlinguistic sounds that mirror prosodic characteristics typical of language and thus carry affective information, but do not convey linguistic information. In a dichotic-listening task, we used these novel stimuli as a means of disambiguating the relative contributions of linguistic and affective processing across the hemispheres. This method was applied to both children and adults with the goal of investigating the role of developing cognitive resource capacity on affective processing. Results suggest that children's limited computational resources influence how they process affective information and rule out attentional biases as a factor in children's perceptual asymmetries for nonlinguistic affective sounds. These data further suggest that investigation of perception of nonlinguistic affective sounds is a valuable tool in assessing interhemispheric asymmetries in affective processing, especially in parceling out linguistic contributions to hemispheric differences. [source] Judgment and action knowledge in speed adjustment tasks: experiments in a virtual environmentDEVELOPMENTAL SCIENCE, Issue 2 2003Susanne Huber Two experiments were conducted to investigate children's and adults' knowledge of time and speed in action and judgment tasks. Participants had to set the speed of a moving car to a new speed so that it would reach a target line at the same time as a reference car moving at a higher speed and disappearing in a tunnel at the midway point. In Experiment 1 (24 10-year-olds, 24 adults), children's and adults' speed adjustments followed the normative pattern when responses had to be graded linearly as a function of the car's initial speed. In a non-linear condition, only adults' action responses corresponded with the normative function. Simplifying the task by shortening the tunnel systematically in Experiment 2 (24 10-year-olds, 24 adults) enabled children to grade the speeds adequately in the action conditions only. Adults now produced normative response patterns in both judgment and action. Whether people show linearization biases was thus shown to depend on the interaction of age, task demands and response mode. [source] The effect of thiazolidinediones on adiponectin serum level: a meta-analysisDIABETES OBESITY & METABOLISM, Issue 5 2008N. Riera-Guardia Background and aims:, Adiponectin is a hormone mainly produced by white adipose tissue. Decreased levels of adiponectin are linked with visceral obesity, insulin resistance states, and cardiovascular diseases. Recently, several studies have pointed out an increase in adiponectin serum levels in subjects undergoing treatment with thiazolidinediones (TZD). The aim of this study is to systematically review the current state of evidence of the effect of TZD on adiponectin serum level with special attention to avoid publication bias. Materials and methods:, An extensive literature search was performed. Meta Analysis Version 2.0 computer program was used to calculate statistical differences in means and 95% confidence interval (CI). Publication bias was assessed using different statistical approaches. Results:, In the meta-analysis including 19 studies the overall standardized mean difference was 0.94 (95% CI, 0.81,1.06) which means that subjects treated with TZDs on average had means of adiponectin concentration that were about 1 standard deviation higher than the comparison groups even after controlling for possible biases. Conclusions:, The results obtained agree with a moderate increase of serum adiponectin. The results clearly reveal an increase of endogenous serum adiponectin levels by intake of TZDs and may point to a potential new option to manage obesity-related diseases. [source] Potential flaws and biases in a randomized controlled trial (RCT) of insulin determir vs. insulin glargine by Pieber and colleaguesDIABETIC MEDICINE, Issue 1 2008J. Alcolado No abstract is available for this article. [source] Randomized controlled trials in schizophrenia: a critical perspective on the literatureACTA PSYCHIATRICA SCANDINAVICA, Issue 4 2002S. Gilbody Objective:,The randomized trial provides an opportunity to minimize the inclusion of biases in the evaluation of interventions in psychiatry. Difficulties arise, however, when applying their results to `real world' clinical practice and decision-making. We, therefore, examined the real world applicability of schizophrenia trials. Method:,A narrative overview of the content and quality of the randomized trials relevant to the care of those with schizophrenia is provided. Results:,Complex, explanatory, under-powered randomized drug trials dominate evaluative research in schizophrenia. Conclusion:,Explanatory designs are a necessary but insufficient step in establishing the true worth of interventions in schizophrenia. Research from other spheres of mental health and wider health care suggest that pragmatic trials are feasible. This design allows large scale trials to be conducted which include patients which we would recognize from routine practice and which record outcomes which are of genuine interest to decision-makers. [source] Can distribution models help refine inventory-based estimates of conservation priority?DIVERSITY AND DISTRIBUTIONS, Issue 4 2010A case study in the Eastern Arc forests of Tanzania, Kenya Abstract Aim, Data shortages mean that conservation priorities can be highly sensitive to historical patterns of exploration. Here, we investigate the potential of regionally focussed species distribution models to elucidate fine-scale patterns of richness, rarity and endemism. Location, Eastern Arc Mountains, Tanzania and Kenya. Methods, Generalized additive models and land cover data are used to estimate the distributions of 452 forest plant taxa (trees, lianas, shrubs and herbs). Presence records from a newly compiled database are regressed against environmental variables in a stepwise multimodel. Estimates of occurrence in forest patches are collated across target groups and analysed alongside inventory-based estimates of conservation priority. Results, Predicted richness is higher than observed richness, with the biggest disparities in regions that have had the least research. North Pare and Nguu in particular are predicted to be more important than the inventory data suggest. Environmental conditions in parts of Nguru could support as many range-restricted and endemic taxa as Uluguru, although realized niches are subject to unknown colonization histories. Concentrations of rare plants are especially high in the Usambaras, a pattern mediated in models by moisture indices, whilst overall richness is better explained by temperature gradients. Tree data dominate the botanical inventory; we find that priorities based on other growth forms might favour the mountains in a different order. Main conclusions, Distribution models can provide conservation planning with high-resolution estimates of richness in well-researched areas, and predictive estimates of conservation importance elsewhere. Spatial and taxonomic biases in the data are essential considerations, as is the spatial scale used for models. We caution that predictive estimates are most uncertain for the species of highest conservation concern, and advocate using models and targeted field assessments iteratively to refine our understanding of which areas should be prioritised for conservation. [source] Wilderness and future conservation priorities in AustraliaDIVERSITY AND DISTRIBUTIONS, Issue 6 2009James E.M. Watson Abstract Aim, Most approaches to conservation prioritization are focused on biodiversity features that are already threatened. While this is necessary in the face of accelerating anthropogenic threats, there have been calls to conserve large intact landscapes, often termed ,wilderness', to ensure the long-term persistence of biodiversity. In this study, we examine the consequences of directing conservation expenditure using a threat-based framework for wilderness conservation. Location, The Australian continent. Methods, We measured the degree of congruence between the extent of wilderness and the Australian protected area network in 2000 and 2006, which was established using a threat-based systematic planning framework. We also assessed priority areas for future reserve acquisitions identified by the Australian government under the current framework. Results, In 2000, 14% of Australia's wilderness was under formal protection, while the protected area network covered only 8.5% of the continent, suggesting a historical bias towards wilderness protection. However, the expansion of the reserve system from 2000 to 2006 was biased towards non-wilderness areas. Moreover, 90% of the wilderness that was protected over this period comprised areas not primarily designated for biodiversity conservation. We found a significant (P < 0.05) negative relationship between bioregions considered to be a priority for future reserve prioritization and the amount of wilderness they contain. Main conclusions, While there is an urgent need to overcome past biases in reserve network design so as to better protect poorly represented species and habitats, prioritization approaches should not become so reactive as to ignore the role that large, intact landscapes play in conserving biodiversity, especially in a time of human-induced climate change. This can be achieved by using current or future threats rather than past threats to prioritize areas, and by incorporating key ecological processes and costs of acquisition and management within the planning framework. [source] How does the knowledge about the spatial distribution of Iberian dung beetle species accumulate over time?DIVERSITY AND DISTRIBUTIONS, Issue 6 2007Jorge M. Lobo ABSTRACT Different distribution maps can be obtained for the same species if localities where species are present are mapped at different times. We analysed the accumulation of information over time for a group of dung beetle species in the Iberian Peninsula. To do this, we used all available information about the distribution of the group as well as data on selected species to examine if the process of discovery of species distribution has occurred in a climatically or spatially structured fashion. Our results show the existence of a well-defined pattern of temporal growth in distributional information; due to this, the date of capture of each specimen can be explained by the environmental and spatial variables associated to the collection sites. We hypothesize that such temporal biases could be the rule rather than the exception in most distributional data. These biases could affect the weighting of environmental factors that influence species distributions, as well as the accuracy of predictive distribution models. Systematic surveys should be a priority for the description of species geographical ranges in order to make robust predictions about the consequences of habitat and climate change for their persistence and conservation. [source] The First-Episode Psychosis Outcome Study: premorbid and baseline characteristics of an epidemiological cohort of 661 first-episode psychosis patientsEARLY INTERVENTION IN PSYCHIATRY, Issue 2 2007Philippe Conus Abstract Aims:, Studies conducted in first-episode psychosis (FEP) samples avoid many biases. However, very few studies are based on epidemiological cohorts treated in specialized FEP services. The aim of this file audit study was to examine premorbid and baseline characteristics of a large epidemiological sample of FEP. Methods:, File audit study of all patients admitted to the Early Psychosis Prevention and Intervention Centre between 1998 and 2000 using a specialized questionnaire. Results:, There were 661 patient files included in the study. Premorbid evaluation revealed high rates of substance use disorder (74.1%), history of psychiatric disorder (47.5%), past traumatic events (82.7%) suicide attempts (14.3%) and family history of psychiatric illness (55.6%). Baseline characteristics revealed high intensity of illness (mean CGI 5.5), high prevalence of lack of insight (62%) and high rate of comorbidity (70%). Conclusion:, High rates of traumatic events or episodes of mental illness before treatment for FEP must be considered when designing treatment approaches because a too narrow focus on positive psychotic symptoms will inevitably lead to incomplete treatment. Additionally, early intervention programmes need sufficient range of resources to address the multiple challenges presented by FEP patients such as high severity of illness, comorbidities and functional impairment. Finally, observation of an important degree of functional impairment despite short duration of untreated psychosis suggests that while early detection of FEP is a necessary step in early intervention, it may not be sufficient to improve functional recovery in psychosis and that efforts aimed at identifying people during the prodromal phase of psychotic disorders should be pursued. [source] Grid-induced biases in connectivity metric implementations that use regular gridsECOGRAPHY, Issue 3 2010Adam G. Dunn Graph-theoretic connectivity analyses provide opportunities to solve problems related to the management, design and maintenance of fragmented landscapes. However, several modern connectivity metrics are implemented using algorithms that are affected by a grid-induced bias. When paths through a regular grid are calculated, distance errors are introduced into the metric outputs, with patterns based on the shape and orientation of the underlying grid structure. The bias is significant in the proposed implementations of the conditional minimum transit cost method introduced by Pinto and Keitt, and the effective resistance method introduced by McRae, Dickson, Keitt and Shah. One solution for ameliorating the bias that affects regular grids is to use an irregular lattice to represent the landscape. The purpose of this paper is to serve as a timely reminder of the grid-induced bias and to provide a demonstration of the irregular grid as a simple solution to the problem. [source] Determining prey distribution patterns from stomach-contents of satellite-tracked high-predators of the Southern OceanECOGRAPHY, Issue 2 2006J. C. Xavier The distribution of many cephalopod, crustacean and fish species in the Southern Ocean, and adjacent waters, is poorly known, particularly during times of the year when research surveys are rare. Analysing the stomach samples of satellite-tracked higher predators has been advocated as a potential method by which such gaps in knowledge can be filled. We examined the viability of this approach through monitoring wandering albatrosses Diomedea exulans at their colony on Bird Island, South Georgia (54°S, 38°W) over the winters (May,July) of 1999 and 2000. At this time, these birds foraged in up to three different water-masses, the Antarctic zone (AZ), the sub-Antarctic zone (SAZ) and the sub-Tropical zone (STZ), which we defined by contemporaneous satellite images of sea surface temperature. A probabilistic model was applied to the tracking and diet data collected from 38 birds to construct a large-scale map of where various prey were captured. Robustness/sensitivity analyses were used to test model assumptions on the time spent foraging and relative catch efficiencies and to evaluate potential biases associated with the model. We were able to predict the distributions of a wide number of cephalopod, crustacean of fish species. We also discovered some of the limitations to using this type of data and proposed ways to rectify these problems. [source] Drug classification: science, politics, both or neither?ADDICTION, Issue 7 2010Harold Kalant ABSTRACT Governments currently classify illicit drugs for various purposes: to guide courts in the sentencing of convicted violators of drug control laws, to prioritize targets of prevention measures and to educate the public about relative risks of the various drugs. It has been proposed that classification should be conducted by scientists and drug experts rather than by politicians, so that it will reflect only accurate factual knowledge of drug effects and risks rather than political biases. Although this is an appealing goal, it is inherently impossible because rank-ordering of the drugs inevitably requires value judgements concerning the different types of harm. Such judgements, even by scientists, depend upon subjective personal criteria and not only upon scientific facts. Moreover, classification that is meant to guide the legal system in controlling dangerous drug use can function only if it is in harmony with the values and sentiments of the public. In some respects, politicians may be better attuned to public attitudes and wishes, and to what policies the public will support, than are scientific experts. The problems inherent in such drug classification are illustrated by the examples of cannabis and of salvinorin A. They raise the question as to whether the classification process really serves any socially beneficial purpose. [source] Host plants and butterfly biology.ECOLOGICAL ENTOMOLOGY, Issue 1 2004Do host-plant strategies drive butterfly status? Abstract., 1.,To determine whether rarity and decline is linked to organism ecology, associations have been examined between butterfly larval host-plant competitive, stress-tolerant, ruderal (C-S-R) strategies and butterfly biology. 2.,Associations have been sought between mean C-S-R scores for larval host plants with butterfly life history, morphology and physiology variables, resource use, population attributes, geography, and conservation status. Comparisons are carried out across species and controlled for phylogenetic patterning. 3.,Butterfly biology is linked to host-plant strategies. An increasing tendency of a butterfly's host plants to a particular strategy biases that butterfly species to functionally linked life-history attributes and resource breadth and type. In turn, population attributes and geography are significantly and substantially affected by host choice and the strategies of these host plants. 4.,The greatest contrast is between butterfly species whose host plants are labelled C and R strategists and those whose host plants are labelled S strategists. Increasingly high host-plant C and R strategy scores bias butterflies to rapid development, short early stages, multivoltinism, long flight periods, early seasonal emergence, higher mobility, polyphagy, wide resource availability and biotope occupancy, open, areally expansive, patchy population structures, denser distributions, wider geographical ranges, resistance to range retractions as well as to increasing rarity in the face of environmental changes. Increasing host-plant S strategy scores have reversed tendencies, biasing those butterfly species to extended development times, fewer broods, short flight periods, smaller wing expanse and lower mobility, monophagy, restricted resource exploitation and biotope occupancy, closed, areally limited populations with typical metapopulation structures, sparse distributions, and limited geographical ranges, range retractions, and increased rarity. 5.,Species with S strategy host plants are species vulnerable to current environmental changes and species of conservation concern. [source] Measuring dispersal and detecting departures from a random walk model in a grasshopper hybrid zoneECOLOGICAL ENTOMOLOGY, Issue 2 2003R. I. Bailey Abstract. 1. The grasshopper species Chorthippus brunneus and C. jacobsi form a complex mosaic hybrid zone in northern Spain. Two mark,release,recapture studies were carried out near the centre of the zone in order to make direct estimates of lifetime dispersal. 2. A model framework based on a simple random walk in homogeneous habitat was extended to include the estimation of philopatry and flying propensity. Each model was compared with the real data, correcting for spatial and temporal biases in the data sets. 3. All four data sets (males and females at each site) deviated significantly from a random walk. Three of the data sets showed strong philopatry and three had a long dispersal tail, indicating a low propensity to move further than predicted by the random walk model. 4. Neighbourhood size estimates were 76 and 227 for the two sites. These estimates may underestimate effective population size, which could be increased by the long tail to the dispersal function. The random walk model overestimates lifetime dispersal and hence the minimum spatial scale of adaptation. 5. Best estimates of lifetime dispersal distance of 7,33 m per generation were considerably lower than a previous indirect estimate of 1344 m per generation. This discrepancy could be influenced by prezygotic isolation, an inherent by-product of mosaic hybrid zone structure. [source] Estimating the number of alcohol-attributable deaths: methodological issues and illustration with French data for 2006ADDICTION, Issue 6 2010Grégoire Rey ABSTRACT Aims Computing the number of alcohol-attributable deaths requires a series of hypotheses. Using French data for 2006, the potential biases are reviewed and the sensitivity of estimates to various hypotheses evaluated. Methods Self-reported alcohol consumption data were derived from large population-based surveys. The risks of occurrence of diseases associated with alcohol consumption and relative risks for all-cause mortality were obtained through literature searches. All-cause and cause-specific population alcohol-attributable fractions (PAAFs) were calculated. In order to account for potential under-reporting, the impact of adjustment on sales data was tested. The 2006 mortality data were restricted to people aged between 15 and 75 years. Results When alcohol consumption distribution was adjusted for sales data, the estimated number of alcohol-attributable deaths, the sum of the cause-specific estimates, was 20 255. Without adjustment, the estimate fell to 7158. Using an all-cause mortality approach, the adjusted number of alcohol-attributable deaths was 15 950, while the non-adjusted estimate was a negative number. Other methodological issues, such as computation based on risk estimates for all causes for ,all countries' or only ,European countries', also influenced the results, but to a lesser extent. Discussion The estimates of the number of alcohol-attributable deaths varied greatly, depending upon the hypothesis used. The most realistic and evidence-based estimate seems to be obtained by adjusting the consumption data for national alcohol sales, and by summing the cause-specific estimates. However, interpretation of the estimates must be cautious in view of their potentially large imprecision. [source] Ecological perspectives on the sequenced genome collectionECOLOGY LETTERS, Issue 12 2005Jennifer B. Hughes Martiny Abstract Our complete genome collection is one of our most valuable biological resources. A key challenge for the future is the interpretation of these genomes from an ecological perspective. In this review, we discuss current work at this increasingly important interface. In particular, we review ongoing work aimed at developing high quality data sets that combine ecological, environmental, evolutionary and genomic information. Such data will help to identify biases in the sequence collection and facilitate future discoveries about the nature of ecological adaptation at the genome level. These efforts will be greatly enhanced by the contributions of ecologists. [source] Evaluation of the effects of catch-and-release angling on the Atlantic salmon (Salmo salar) of the Ponoi River, Kola Peninsula, Russian FederationECOLOGY OF FRESHWATER FISH, Issue 1-2 2000F. G. Whoriskey Abstract , We studied the effects of catch-and-release fishing upon the Ponoi River's Atlantic salmon populations. The Ponoi River is located on the Kola Peninsula of the Russian Federation, and has recently been developed for sports fishing. Angler exploitation rates are estimated to range from 10.4% to 19% of the river's salmon, thus the possibility of significant levels of post-release mortality is of concern. We radio-tracked fish caught and released by anglers in 1995 and 1996. Despite our simple equipment and the large size of the river, we were able to relocate most fish. These fish had high rates of survival, and anglers recaptured about 11% of them per year a second time. This is very similar to the recapture rates observed for Floy-tagged fish released in an angler-based mark-recapture assessment. We also held 62 angled fish for 24 hours in a live cage to evaluate rates of delayed mortality. Only one of the 62 fish died, and it was heavily scarred with gillnet marks. Most fish that are fatally stressed by angling die within 24 h (e.g., Booth et al. 1995). In 1996, up to 10% of our Floy-tagged fish were angled and released twice, and about 0.5% were angled and released three times. No significant biases were detected in the post-angling movement patterns of these fish. The multiple captures and lack of movement bias suggest that fish behavior was little altered by the angling experience. Nine fish Floy tagged prior to spawning have been recovered as typical emaciated kelts. Three were killed, and a post mortem exam showed all had spawned. Parr numbers at all monitored sites have been steadily increasing since the advent of catch-and-release fishing. By contrast, parr growth rates are generally unchanged or significantly better., [source] | |||||||||||||||||||||||||||||||||||||