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Significant Negative Effects (significant + negative_effects)
Selected AbstractsAge, period and cohort influences on beer, wine and spirits consumption trends in the US National Alcohol SurveysADDICTION, Issue 9 2004William C. Kerr ABSTRACT Aims To estimate the separate influences of age, period and cohort on the consumption of beer wine and spirits in the United States. Design Linear age,period,cohort models controlling for demographic change with extensive specification testing. Setting US general population 1979,2000. Measurements Monthly average of past-year consumption of beer, wine and spirits in five National Alcohol Surveys. Findings The strongest cohort effects are found for spirits; cohorts born before 1940 are found to have significantly higher consumption than those born after 1946, with especially high spirits consumption for men in the pre-1930s cohorts. Significant cohort effects are also found for beer with elevated consumption in the 1946,65 cohorts for men but in the pre-1940 cohorts for women. Significant negative effects of age are found for beer and spirits consumption, although not for wine. Significant period effects are found for men's beer and wine consumption and for women's spirits consumption. Increased educational attainment in the population over time is associated with reduced beer consumption and increased wine consumption. Conclusions Changing cohort demographics are found to have significant effects on beverage-specific consumption, indicating the importance of controlling for these effects in the evaluation of alcohol policy effectiveness and the potential for substantial improvement in the forecasting of future beverage-specific consumption trends, alcohol dependence treatment demand and morbidity and mortality outcomes. [source] Effects of fertilization on understorey vegetation in a Norwegian Pinus sylvestris forestAPPLIED VEGETATION SCIENCE, Issue 2 2002Astrid Skrindo Abstract. Boreal coniferous forests have been impacted by long distance airborne pollutant deposition for most of the 20th century. Changes in forest understorey vegetation attributable to N-deposition have been observed in southern Sweden, but not so far in southern Norway. We recorded the quantity of all species of vascular plants, bryophytes and lichens in 144 plots in a fertilization experiment in a 35-yr old Pinus sylvestris forest in Aust Agder County, southernNorway initiated 6 yr before our study. Each plot represented a combination of three levels of nitrogen, two levels of magnesium and two levels of phosphorus addition. Effects of fertilization on species quantity were tested by Kruskal-Wallis one-way analysis by ranks. For vascular plants, only small and hardly significant differences were found between treatments and control. Significant negative effects of N-fertilization were found on both mosses and lichens. To some extent, these effects could be attributed to direct effects of application of the fertilizer, but were more likely to be due to a negative feedback response to the faster growth of pine trees in fertilized stands, reducing throughfall precipitation and increasing litter fall. Significant differences between Mg- and P-fertilized sites and respective controls were found for too few species to be likely to represent an overall trend. [source] Effects of Rock Climbing on the Land Snail Community of the Niagara Escarpment in Southern Ontario, CanadaCONSERVATION BIOLOGY, Issue 2 2003Michele A. McMillan We examined the effects of rock climbing on the density, richness, diversity, and community composition of snails on the Niagara Escarpment in southern Ontario, Canada. We sampled from randomly selected climbed and unclimbed sections of cliffs on the plateau ( cliff edge ), cliff face, and talus ( cliff base ). Snail density, richness, and diversity were lower along climbing routes than in unclimbed areas, and community composition differed between climbed and unclimbed samples. These results suggest that rock climbing has significant negative effects on all aspects of the snail community on cliffs; therefore, we recommend the inclusion of gastropods in conservation plans for protected areas containing cliffs. Resumen: Las barrancas del acantilado del Niagara proveen hábitat para comunidades extremadamente diversas de caracoles terrestres que pueden estar en riesgo debido al alpinismo recreativo. Examinamos los efectos del alpinismo en la densidad, riqueza, diversidad y composición de comunidades de caracoles del acantilado del Niagara en Ontario Meridional, Canadá. Tomamos muestras de las mesetas ( bordes de acantilados ), la cara del acantilado y el talud ( base del acantilado ) de secciones de barrancas usadas y no usadas para el alpinismo y seleccionadas al azar. La densidad, la riqueza y la diversidad de caracoles fueron más bajas en las rutas escaladas que en aquellas áreas no escaladas y la composición de la comunidad difirió entre muestras escaladas y no escaladas. Estos resultados sugieren que el alpinismo tiene impactos negativos significativos en todos los aspectos de la comunidad de caracoles en acantilados; por lo tanto, recomendamos la inclusión de gasterópodos en los planes de conservación para áreas protegidas que contengan acantilados. [source] Response Time of Wetland Biodiversity to Road Construction on Adjacent LandsCONSERVATION BIOLOGY, Issue 1 2000C. Scot T Findlay Species loss is unlikely to occur immediately, however. Rather, populations of susceptible species are expected to decline gradually after road construction, with local extinction occurring sometime later. We document lags in wetland biodiversity loss in response to road construction by fitting regression models that express species richness of different taxa ( birds, mammals, plants, and herptiles) as a function of both current and historical road densities on adjacent lands. The proportion of variation in herptile and bird richness explained by road densities increased significantly when past densities were substituted for more current densities in multiple regression models. Moreover, for vascular plants, birds, and herptiles, there were significant negative effects of historical road densities when the most current densities were controlled statistically. Our results provide evidence that the full effects of road construction on wetland biodiversity may be undetectable in some taxa for decades. Such lags in response to changes in anthropogenic stress have important implications for land-use planning and environmental impact assessment. Resumen: La construcción de caminos puede resultar en significativas pérdidas de biodiversidad tanto a escala local como regional debido a la restricción de movimiento entre poblaciones, incremento de la mortalidad, fragmentación de hábitat y efectos de borde, invasión de especies exóticas o mayor acceso de humanos a hábitats silvestres, con lo cual se espera que se incrementen las tasas locales de extinción o disminuyan las tasas locales de recolonización. Sin embargo, es improbable que la pérdida de especies ocurra inmediatamente. Más bien, se espera que las poblaciones de especies susceptibles declinen gradualmente después de la construcción del camino, extinguiéndose localmente poco tiempo después. Documentamos la pérdida de biodiversidad en humedales como respuesta a la construcción de caminos ajustando modelos de regresión que expresan la riqueza de especies de diferentes taxa (aves, mamíferos, plantas, reptiles y anfibios) como una función de las densidades actual e histórica de los caminos en tierras adyacentes. La proporción de variación en anfibios, reptiles y aves incrementó significativamente cuando las densidades históricas fueron sustituidas por densidades actuales en los modelos de regresión múltiple. Más aun, hubo efectos negativos significativos de las densidades de caminos históricas para plantas vasculares, aves, anfibios y reptiles cuando las densidades actuales fueron estadísticamente controladas. Nuestros resultados proporcionan evidencia de que los efectos de la construcción de caminos sobre la biodiversidad de humedales pueden se indetectables para algunos taxa por décadas. Tales rezagos en la respuesta a cambios en el estrés antropogénico tienen implicaciones importantes en la planificación de uso del suelo y la evaluación de impacto ambiental. [source] Foreign direct investment and the dark side of decentralizationECONOMIC POLICY, Issue 49 2007Sebastian G. Kessing SUMMARY Fiscal decentralization VERTICAL, HORIZONTAL, AND FDI Both in the developed and developing world, decentralization of fiscal policy is frequently argued to foster investment, because allowing investors to choose between competing locations should make it difficult for each jurisdiction to tax the investment's returns. We point out that this ,horizontal' dimension of decentralization cannot eliminate ex post incentives to tax investments once they are irreversibly located in a jurisdiction, and that the negative ex ante investment effects of such ,hold up' problems are actually stronger when decentralization inevitably leads to multiple levels of taxation power in each location. Empirically, we detect significant negative effects on FDI of the ,vertical' dimension of decentralization, measured by the number of government layers, in a data set containing many countries and many suitable control variables. Indicators of overall fiscal decentralization do not appear to affect the investment climate negatively per se, but our theoretical arguments and empirical results suggest that policymakers should consider very carefully the form and degree of government decentralization if they aim at improving the investment climate. , Sebastian G. Kessing, Kai A. Konrad and Christos Kotsogiannis [source] Longitudinal Effects of Hope on Depression and Anxiety: A Latent Variable AnalysisJOURNAL OF PERSONALITY, Issue 1 2007Randolph C. Arnau ABSTRACT This study tested the prospective effects of hope on depression and anxiety using a longitudinal design. A sample of 522 college students completed self-report measures of hope, depression, and anxiety at three time points, with 1-month delays between administrations. Structural equation modeling was employed to test two cross-lagged panel models of the reciprocal effects of the Agency and Pathways components of hope on depression and anxiety. Results indicated statistically significant negative effects for the Agency component of hope on later depression but no unique effect of the Pathways component of hope on depression. Likewise, Agency showed a statistically significant negative effect on later anxiety, but again Pathways had no significant influence on anxiety. In both cases, neither depression nor anxiety demonstrated any longitudinal effects on either the Agency or Pathways components of hope. Implications of these findings are discussed, along with potential directions for future research. [source] Relational Aggression and Adverse Psychosocial and Physical Health Symptoms Among Urban AdolescentsPUBLIC HEALTH NURSING, Issue 6 2009Jessica Roberts Williams ABSTRACT Objectives: The purpose of this study was to examine relational aggression and its relationship with adverse psychosocial and physical health symptoms among urban, African American youth. Design and Sample: Quantitative, cross-sectional survey design. The sample consisted of 185 predominantly African American (95.1%) seventh-grade students (mean age: 13.0; female: 58%) attending 4 urban middle schools. Measures: The Children's Social Behavior Scale and Social Experience Questionnaire were used to measure relational aggression and relational victimization. The Pediatric Symptom Checklist was used to assess psychosocial difficulties, including internalizing behaviors, externalizing behaviors, and attention problems. Physical health symptoms were measured with questions about colds/flu, headaches, and stomach aches. Results: 2-way multivariate analysis of variance revealed significant differences in externalizing behavior, with perpetrators reporting higher levels than nonperpetrators. Victims reported more internalizing behavior than nonvictims; however, this was only significant for males. For females, significant negative effects on health outcomes were found, resulting from the interaction of perpetration and victimization. Conclusions: Findings suggest that relational aggression is a common occurrence among urban, minority adolescents and may result in adverse health outcomes. These results provide several avenues for future research and implications for healthcare practice. Intervention strategies are needed to prevent relational aggression and continual or subsequent adverse health symptoms. [source] Cryotolerance of Bovine Blastocysts is Affected by Oocyte Maturation in Media Containing Palmitic or Stearic AcidREPRODUCTION IN DOMESTIC ANIMALS, Issue 1 2009MA Shehab-El-Deen Contents In this study, non-esterified fatty acids (NEFAs) were added during in vitro maturation at concentrations measured previously in follicular fluid (FF) of high-producing dairy cows in a negative energy status to evaluate their subsequent effect on the embryos cryotolerance. Oocytes were matured for 24 h in serum-free media with or without (negative control) the addition of NEFAs dissolved in ethanol or ethanol alone (positive control). Matured oocytes were fertilized and cultured for 7 days in synthetic oviduct fluid medium supplemented with 5% FCS. Embryos that had at least reached the blastocyst stage were vitrified by open pulled straw (OPS) vitrification. Addition of palmitic (C16 : 0) or stearic acid (C18 : 0) during oocyte maturation had significant negative effects on embryo cryotolerance, whereas ethanol or oleic acid (C18 : 1) had no effect. These in vitro results suggest that high NEFA concentrations in FF during a period of negative energy balance in high-yielding dairy cows can have carry-over effects on embryo quality. [source] Revisiting the empirical estimation of the effect of margin changes on futures trading volumeTHE JOURNAL OF FUTURES MARKETS, Issue 6 2003Hans R. Dutt This study revisits the empirical estimation of the effect of margin requirements on trading volume. Although theory suggests that margin requirements impose a cost to traders and will therefore likely reduce volume traded, empirical examinations have generally failed to find this association. The contention of this article is that the theory is correct, but empirical estimation has generally neglected to adjust margins for underlying price risk. After adjusting for risk, this analysis finds economically and statistically significant negative effects of margin requirements on trading volume as predicted by theory. This study examined 6 contracts over a 17-year time period and found that financial futures contracts (gold, Dow Jones, and 10-Year Treasury Notes) were considerably more sensitive to changes in margin requirements than agricultural futures (wheat, corn, and oats). © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:561,576, 2003 [source] The mortality of Helicoverpa armigera (Hübner) (Lepidoptera: Noctuidae) neonate larvae in relation to drop-off and soil surface temperature: the dangers of bungy jumpingAUSTRALIAN JOURNAL OF ENTOMOLOGY, Issue 4 2008David J Perovi Abstract The first larval instar has been identified as a critical stage for population mortality in Lepidoptera, yet due to the body size of these larvae, the factors that contribute to mortality under field conditions are still not clear. Dispersal behaviour has been suggested as a significant, but ignored factor contributing to mortality in first-instar lepidopteran larvae. The impact that leaving the host plant has on the mortality rate of Helicoverpa armigera neonates was examined in field crops and laboratory trials. In this study the following are examined: (1) the effects of soil surface temperature, and the level of shade within the crop, on the mortality of neonates on the soil after dropping off from the host plant; (2) the percentage of neonates that dropped off from a host plant and landed on the soil; and (3) the effects of exposure to different soil surface temperatures on the development and mortality of neonates. The findings of this study showed that: (1) on the soil, surface temperatures above 43°C were lethal for neonates, and exposure to these temperatures contributed greatly to the overall mortality rate observed; however, the fate of neonates on the soil varied significantly depending on canopy closure within the crop; (2) at least 15% of neonates dropped off from the host plant and landed on the soil, meaning that the proportion of neonates exposed to these condition is not trivial; and (3) 30 min exposure to soil surface temperatures approaching the lethal level (>43°C) has no significant negative effects on the development and mortality of larvae through to the second instar. Overall leaving the plant through drop-off contributes to first-instar mortality in crops with open canopies; however, survival of neonates that have lost contact with a host plant is possible, and becomes more likely later in the crop growing season. [source] | ||||||||||||||||