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Research Suggesting (research + suggesting)
Selected AbstractsPrescribing Flood Regimes to Sustain Riparian Ecosystems along Meandering RiversCONSERVATION BIOLOGY, Issue 5 2000Brian D. Richter By managing river flows for water supplies and power generation, water management agencies have inadvertently caused considerable degradation of riverine ecosystems and associated biodiversity. New approaches for meeting human needs for water while conserving the ecological integrity of riverine ecosystems are greatly needed. We describe an approach for identifying the natural flooding characteristics that must be protected or restored to maintain riparian ( floodplain) ecosystems along meandering rivers. We developed a computer model to simulate flood-driven changes in the relative abundance of riparian patch types along the Yampa River in Colorado ( U.S.A.). The model is based on research suggesting that the duration of flooding at or above 209 m3 per second (125% of bankfull discharge) is particularly important in driving lateral channel migration, which is responsible for initiating ecological succession in the Yampa's riparian forest. Other hydrologic variables, such as the magnitude of annual peak flows, were not as strongly correlated with lateral channel migration rates. Model simulations enabled us to tentatively identify a threshold of alteration of flood duration that could lead to substantial changes in the abundance of forest patch types over time should river flows be regulated by future water projects. Based on this analysis, we suggest an ecologically compatible water management approach that avoids crossing flood alteration thresholds and provides opportunity to use a portion of flood waters for human purposes. Recommended improvements to the Yampa model include obtaining additional low-elevation aerial photographs of the river corridor to enable better estimation of channel migration rates and vegetation changes. These additional data should greatly improve the model's accuracy and predictive capabilities and therefore its management value. Resumen: La composición y estructura de ecosistemas ribereños están fuertemente ligadas a la variabilidad hidrológica natural. Al manejar el flujo de ríos para abastecer agua y generar energía, las agencias de manejo de agua han causado inadvertidamente una degradación considerable de los ecosistemas ribereños y la biodiversidad asociada a ellos. Se necesitan nuevas estrategias para satisfacer las necesidades humanas de agua al mismo tiempo que se conserva la integridad de los ecosistemas ribereños. Describimos una estrategia para identificar las características de inundaciones naturales que deben ser protegidas o restauradas para mantener ecosistemas riparios ( planicies de inundación) a lo largo de ríos sinuosos. Desarrollamos un modelo de computadora para simular los cambios causados por inundaciones en la abundancia relativa de tipos de parche ripario a lo largo del río Yampa, en Colorado ( Estados Unidos de Norteamérica). Este modelo se basa en investigación que sugiere que la duración de la inundación a, o mayor a, 209 m3 por segundo (125% de descarga del banco lleno a su capacidad) es particularmente importante en la conducción de la migración de canales laterales, lo cual es responsable de la iniciación de la sucesión ecológica en el bosque ripario del río Yampa. Otras variables hidrológicas, como lo es la magnitud del pico de los flujos anuales no estuvieron tan fuertemente correlacionadas con las tasas de migración lateral de canales. Las simulaciones del modelo nos permitieron identificar límites tentativos de alteración de la duración de la inundación que podrían conducir a cambios sustanciales en la abundancia de tipos de parches forestales en el tiempo si los flujos de los ríos son regulados en proyectos de agua futuros. En base a este análisis, sugerimos una estrategia de manejo de agua ecológicamente compatible que evita sobrepasar los límites de alteración de las inundaciones y provee la oportunidad de usar una porción del agua de las inundaciones para fines humanos. Las recomendaciones de mejoras al modelo del río Yampa incluyen la necesidad de obtener fotografías aéreas de baja elevación adicionales del corredor del río, que permitan una mejor estimación de las tasas de migración de los canales y los cambios en la vegetación. Estos datos adicionales deberán mejorar en gran medida la precisión del modelo y sus capacidades predictivas y, por lo tanto, su valor de manejo. [source] Behavioural Syndromes in Urban and Rural Populations of Song SparrowsETHOLOGY, Issue 7 2010Jackson Evans Animals in urban habitats are often noticeably bold in the presence of humans. Such boldness may arise due to habituation, as urban animals learn, through repeated exposure, that passing humans do not represent a threat. However, there is growing research suggesting that: (1) inherent traits, as opposed to learned behaviour, influence which species invade urban habitats, and (2) individuals exhibit individual personality traits that limit behavioural flexibility, with the possible result that not all individuals would be able to demonstrate an appropriate level of boldness in urban environments. As a result, perhaps only birds with inherently bold personalities could successfully settle in an area of high human disturbance, and further, we might also expect to see the existence of behavioural syndromes, where boldness is correlated with variation in other behavioural traits such as aggression. In this study, we examined boldness and territorial aggression in urban and rural populations of song sparrows. We found that urban birds were bolder towards humans and that urban birds also showed higher levels of territorial aggression. We also found an overall correlation between boldness and territorial aggression, suggesting that urban boldness may be part of a behavioural syndrome. However, we see no correlation between boldness and aggression in the urban population, and thus, more work is needed to determine the mechanisms accounting for high levels of boldness and aggression urban song sparrows. [source] Nature, extent, and causes of bullying among personality-disordered patients in a high-secure hospitalAGGRESSIVE BEHAVIOR, Issue 3 2004Jane L. Ireland Abstract The present study explored the perceptions and experiences of the nature, extent and causes of bullying among personality-disordered patients, with a subsidiary aim of exploring differences in perceptions between staff and patients. The sample was selected from the Personality Disorder Unit of a high secure hospital. The total sample consisted of 60 participants, 30 patients and 30 staff. Participants engaged in a semi-structured interview based on that developed by Brookes [1993] and modified by Ireland and Archer [1996] and Ireland [2002a]. The interview assessed their perceptions and experiences of patient-to-patient bullying. One fifth of patients and staff reported that they had seen a patient being bullied in the previous week. One-fifth of patients reported that they had been bullied in the previous week and less than one tenth reported that they had bullied others. The most frequent types of bullying reported were theft-related, verbal abuse, being made to do chores, physical assaults and intimidation. One fifth of the sample reported that sexual abuse took place. Victims were generally perceived to be ,easy targets' that were vulnerable, either physically or emotionally. Staff identified a wider range of victim types than patients. The results highlight how patient-to-patient bullying does occur and is an important issue worthy of further research. A number of similarities were found between the current findings and those of prison-based research suggesting that both hospitals and prisons share a number of environmental similarities that help to explain why bullying takes placed in secure forensic settings. Aggr. Behav. 30:229,242, 2004. © 2004 Wiley-Liss, Inc. [source] Associations Among GABRG1, Level of Response to Alcohol, and Drinking BehaviorsALCOHOLISM, Issue 8 2009Lara A. Ray Background:, Recent studies of the genetics of alcoholism have focused on a cluster of genes encoding for ,-aminobutyric acid (GABAA) receptor subunits, which is thought to play a role in the expression of addiction phenotypes. This study examined allelic associations between 2 single nucleotide polymorphisms (SNPs) of the GABRG1 gene (rs1391166 and rs1497571) and alcohol phenotypes, namely level of response to alcohol, alcohol use patterns, and alcohol-related problems. Method:, Participants were non-treatment-seeking seeking hazardous drinkers (n = 124) who provided DNA samples, participated in a face-to-face interview for level of response to alcohol, and completed a series of drinking and individual differences measures. Results:, Analyses revealed that a SNP of the GABRG1 gene (rs1497571) was associated with level of response to alcohol and drinking patterns in this subclinical sample. Follow-up mediational analyses were also conducted to examine putative mechanisms underlying these associations. Discussion:, These findings replicate and extend recent research suggesting that genetic variation at the GABRG1 locus may underlie the expression of alcohol phenotypes, including level of response to alcohol. [source] Teaching science problem solving: An overview of experimental workJOURNAL OF RESEARCH IN SCIENCE TEACHING, Issue 4 2001R. Taconis The traditional approach to teaching science problem solving is having the students work individually on a large number of problems. This approach has long been overtaken by research suggesting and testing other methods, which are expected to be more effective. To get an overview of the characteristics of good and innovative problem-solving teaching strategies, we performed an analysis of a number of articles published between 1985 and 1995 in high-standard international journals, describing experimental research into the effectiveness of a wide variety of teaching strategies for science problem solving. To characterize the teaching strategies found, we used a model of the capacities needed for effective science problem solving, composed of a knowledge base and a skills base. The relations between the cognitive capacities required by the experimental or control treatments and those of the model were specified and used as independent variables. Other independent variables were learning conditions such as feedback and group work. As a dependent variable we used standardized learning effects. We identified 22 articles describing 40 experiments that met the standards we deemed necessary for a meta-analysis. These experiments were analyzed both with quantitative (correlational) methods and with a systematic qualitative method. A few of the independent variables were found to characterize effective strategies for teaching science problem solving. Effective treatments all gave attention to the structure and function (the schemata) of the knowledge base, whereas attention to knowledge of strategy and the practice of problem solving turned out to have little effect. As for learning conditions, both providing the learners with guidelines and criteria they can use in judging their own problem-solving process and products, and providing immediate feedback to them were found to be important prerequisites for the acquisition of problem-solving skills. Group work did not lead to positive effects unless combined with other variables, such as guidelines and feedback. © 2001 John Wiley & Sons, Inc. J Res Sci Teach 38: 442,468, 2001 [source] A Polymorphism of the ,-Opioid Receptor Gene (OPRM1) and Sensitivity to the Effects of Alcohol in HumansALCOHOLISM, Issue 12 2004Lara A. Ray Background: Recent research has implicated the endogenous opioid system in the development of alcohol use disorders. The A118G polymorphism of the OPRM1 gene has been shown to confer functional differences to ,-opioid receptors, such that the G variant binds ,-endorphin three times more strongly than the A variant. The goal of this study was to test whether the A118G polymorphism is associated with sensitivity to the effects of alcohol. Methods: Participants who were either homozygous for the A allele (n= 23) or heterozygous (n= 15) received intravenous doses of alcohol designed to reach three target levels of breath alcohol concentration: 0.02, 0.04, and 0.06. The testing procedure consisted of measures of subjective intoxication, stimulation, sedation, and mood states at baseline and at each of the three target breath alcohol concentrations. Results: The results suggested that individuals with the G allele reported higher subjective feelings of intoxication, stimulation, sedation, and happiness across trials as compared with participants with the A allele. Furthermore, participants with the G allele were almost three times more likely to report a positive family history of alcohol use disorders than participants with the A allele. Conclusions: These findings may help to explain previous research suggesting that naltrexone is more effective among individuals with the G allele. A medication that reduces feelings of euphoria after alcohol consumption may be more successful among individuals with a genetic predisposition to greater feelings of euphoria after consuming alcohol. [source] Cultural consonance and body morphology: Estimates with longitudinal data from an Amazonian societyAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Victoria Reyes-García Abstract Researchers have hypothesized that the degree to which an individual's actual behavior approximates the culturally valued lifestyle encoded in the dominant cultural model has consequences for physical and mental health. We contribute to this line of research by analyzing data from a longitudinal study composed of five annual surveys (2002,2006 inclusive) from 791 adults in one society of foragers,farmers in the Bolivian Amazon, the Tsimane'. We estimate the association between a standard measure of individual achievement of the cultural model, cultural consonance, and three indicators of body morphology. Drawing on research suggesting that in societies in the early stages of economic development an increase in socioeconomic status is associated with an increase in mean body mass, we expect to find a positive association between cultural consonance and three anthropometric measures. We found the expected positive association between cultural consonance and anthropometric measures,especially for men,only when using ordinary least square (OLS) regression models, but not when using fixed-effects regression models. The real magnitude of the association was low. The comparison of estimates from OLS and fixed-effect regression models suggests that previous findings on the effects of cultural consonance on body morphology using cross-sectional data should be read with caution because the association might be largely explained by fixed characteristics of individuals not accounted in OLS models. Am J Phys Anthropol 143:167,174, 2010. © 2010 Wiley-Liss, Inc. [source] Testing the boundaries of the choice overload phenomenon: The effect of number of options and time pressure on decision difficulty and satisfactionPSYCHOLOGY & MARKETING, Issue 3 2009Graeme A. Haynes The number of alternatives available to people in many day-to-day decisions has greatly increased in Western societies. The present research sought to build upon recent research suggesting that having large numbers of alternatives can sometimes have negative consequences for individuals. In the present experiment, participants were presented with descriptions of either 3 or 10 prizes and asked to choose one, for which they were to be entered in a drawing. The number of alternatives was manipulated in conjunction with the amount of time people were allotted to make a decision (limited vs. extended decision time). Following their decisions, participants completed measures of decision-related difficulty, task enjoyment, satisfaction, and regret. Participants given a limited amount of time to choose with a larger set of alternatives found their decisions to be more difficult and frustrating than did participants in the other conditions. The larger set of alternatives led to less satisfaction, but not less regret, with people's decisions. Implications for research on the choice overload phenomenon are discussed. © 2009 Wiley Periodicals, Inc. [source] Reconstructing Rituals: Expressions of Autonomy and Resistance in a Sino-Indonesian SchoolANTHROPOLOGY & EDUCATION QUARTERLY, Issue 4 2002Assistant Professor Christopher BjorkArticle first published online: 8 JAN 200 This article examines the role that rituals enacted in an Indonesian school for Chinese play in shaping behavior, inculcating values, and sustaining a learning community. The analysis draws from research suggesting that school rituals may promote the interests of the dominant culture, but can also function counterhegemonically, creating opportunities for subordinate groups to promote their own interests. In the hands of teachers at St. Timothy's Junior High, activities designed to venerate national cohesion were revised to highlight the school's independence from the central government and the dominant culture. This evidence adds to recent literature suggesting that hegemony is not always unidirectionally imposed on students, and reveals formations of resistance that diverge from the common student versus school model. [source] | ||||||||||