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Additional Considerations (additional + consideration)
Selected AbstractsImplications of Climatic Warming for Conservation of Native Trees and Shrubs in FloridaCONSERVATION BIOLOGY, Issue 4 2001David W. Crumpacker Climatic-envelope models are useful for simultaneous investigation of many plant species whose range-limiting mechanisms are poorly known. They are most effectively applied in regions with strong temperature and moisture gradients and low relief. Their required databases are often relatively easy to obtain. We provide an example involving the effect of six annual warming scenarios, ranging from +1° C to +2° C and from +10% to ,20% annual precipitation (some have greater warming in winter than in summer), on 117 native woody species in Florida (U.S.A.). Tree species at their southern range boundaries in several parts of Florida are likely to be negatively affected by as little as 1° C warming if it is greater in winter than in summer or is accompanied by a 20% decrease in annual precipitation. Potential species responses to an identical type of 1° C warming may be different for some conservation areas in the same region of Florida. Potentially extensive disruption of some major woody ecosystems is predicted under certain types of 1° C annual warming and under all types of 2° C annual warming that were investigated. Additional consideration of nonclimatic factors suggests that many potential effects on species and ecosystems are not underestimates of actual effects over a 100-year period of warming. We recommend monitoring for decreased fertility and viability of ecologically important, temperate woody species near their southern range limits in Florida. Early detection of such changes in fitness might then provide time for mitigations designed to alleviate more serious subsequent effects on biodiversity. Control of invasive, non-native plant species and prevention of their additional introduction, human-assisted translocation of native subtropical plant species into previously temperate parts of Florida, and restoration of more natural hydrological regimes are examples of potentially useful mitigations if climatic warming continues. Resumen: Los modelos de procesos ecológicos y los modelos empíricos han sido usados para relacionar predicciones de cambio climático con los efectos en especies de plantas y vegetación. Los modelos climáticos son útiles para la investigación simultánea de muchas especies de plantas cuyos mecanismos limitantes de rango son poco conocidos. Estos modelos son más eficientemente aplicados en regiones con gradientes de temperatura y humedad fuertes y con relieve bajo. Las bases de datos requeridas son a menudo relativamente fáciles de adquirir. Proveemos un ejemplo que involucra el efecto de seis escenarios anuales de calentamiento con un rango de +1° C a +2° C y de +10% a ,20% de precipitación anual (algunos con rangos de calentamiento mayores en el invierno que en el verano), en 117 especies leñosas nativas de Florida ( E.U.A.). Las especies de árboles en sus límites de rango al sur en diversas partes de Florida son más factibles de ser negativamente afectadas por tan poco como 1° C de calentamiento, si este es mayor en el invierno que en el verano o si es acompañado por una disminución de un 20% de precipitación anual. Las respuestas potenciales de las especies a un tipo idéntico de calentamiento de 1° C puede ser diferente para algunas áreas de conservación en la misma región de Florida. Se predicen perturbaciones potencialmente extensivas en algunos ecosistemas leñosos principales investigados bajo ciertos tipos de calentamiento anual de 1° C y bajo todos los tipos de calentamiento anual de 2° C. Las consideraciones adicionales de factores no climáticos sugieren que muchos efectos potenciales sobre las especies y ecosistemas no son subestimaciones de los efectos actuales sobre un período de calentamiento de 100 años. Se recomienda el monitoreo de la disminución de la fertilidad y viabilidad de especies leñosas templadas ecológicamente importantes cerca de los límites sureños de sus rangos en la Florida. La detección temprana de estos cambios en adaptabilidad pueden proveer tiempo para mitigaciones diseñadas para aliviar efectos posteriores más serios en la biodiversidad. Algunos ejemplos de mitigaciones potencialmente útiles en caso de que el calentamiento global continúe incluyen el control de especies de plantas invasoras no nativas y la prevención de su introducción adicional, la translocación asistida por humanos de plantas nativas subtropicales en partes previamente templadas de Florida y la restauración de regimenes hidrológicos más naturales. [source] An Evaluation of the Compensation Required by European Union Cereal Growers to Accept the Removal of Price SupportJOURNAL OF AGRICULTURAL ECONOMICS, Issue 3 2003Rob Fraser Motivated by the policy trend of exposing European Union farmers to more market risk by reducing price support, this paper evaluates the compensation required by EU cereal growers to accept the complete removal of price support. Additional considerations are whether this policy change also includes the removal of set-aside, or features only a partial removal of price support. A model is developed which captures the main on- and off-farm factors influencing grower perceptions of the impact of this policy change. This model is subjected to a numerical analysis which shows that divergent assessments of the expected profitability of releasing to production land previously set-aside mean growers are unlikely to agree whether compensation is even required. It is concluded that the retention of set-aside for environmental purposes is likely to mean growers are more united in their perception of the need for, and amount of, compensation to accept the removal of price support. [source] Free tissue transfer in pregnancy: Guidelines for perioperative managementMICROSURGERY, Issue 5 2001G. Robert Meger M.D. A successful free tissue transfer of serratus anterior muscle, to provide coverage for an open ankle defect in a pregnant patient, is described. Microvascular surgery in the presence of a viable pregnancy demands considerations unique to this situation. Although rarely possible, an attempt should be made to plan surgery to coincide with the second trimester, to lessen the risk of anesthesia to the fetus. Maternal positioning, fluid balance, and aspiration precautions need to be critically addressed. Close perioperative monitoring by an obstetrician is essential. The condition of pregnancy results in a hypercoagulable state that may lead to an increased risk of anastomotic failure. The use of anticoagulants results in increased risk of bleeding, not only for the patient but also for the fetus, as well as risk of teratogenic effects. Closely monitored heparin is considered safe in pregnancy as is low-molecular-weight dextran and low-dose aspirin. Additional considerations include the use of narcotics and sedatives for comfort postoperatively, as well as antibiotic choices, if indicated. © 2001 Wiley-Liss, Inc. Microsurgery 21:202,207 2001 [source] Compartmental factors influencing tear film osmolarityACTA OPHTHALMOLOGICA, Issue 2008AJ BRON Purpose To illustrate how compartmental factors could influence the distribution of tear osmolarity at the ocular surface in normals and dry eye. Methods Mathematical modelling using parameters in the literature. Results Tear film hyperosmolarity is a final common pathway causing ocular surface damage in dry eye. Modelling predicts that tear osmolarity is higher in the tear film than the meniscus, which may influence the distribution of ocular surface damage and the initiation of symptoms caused by hyperosmolarity. Once tear film break up occurs within the blink interval it is likely that this differential is amplified locally. The model allows the effect of compartmental factors on tear osmolarity to be addressed, including: regional differences in air flow and surface temperature, variations in ambient temperature and humidity, imperfect tear mixing, differential corneal and conjunctival exposure and individual differences in reflex tear flow, evaporation rate and blink interval. We hypothesise that interactions between these factors determine the dry eye phenotype in an individual. Additional considerations suggest that events at the ocular surface differ in aqueous-deficient and evaporative dry eye. Conclusion Hyperosmolarity at the ocular surface is affected by multiple factors, each of which may make different contributions to distribution and severity of surface damage in a given individual. This may determine the phenotype, frequency and severity of dry eye in a population. [source] ESTIMATING A GEOGRAPHICALLY EXPLICIT MODEL OF POPULATION DIVERGENCEEVOLUTION, Issue 3 2007L. Lacey Knowles Patterns of genetic variation can provide valuable insights for deciphering the relative roles of different evolutionary processes in species differentiation. However, population-genetic models for studying divergence in geographically structured species are generally lacking. Since these are the biogeographic settings where genetic drift is expected to predominate, not only are population-genetic tests of hypotheses in geographically structured species constrained, but generalizations about the evolutionary processes that promote species divergence may also be potentially biased. Here we estimate a population-divergence model in montane grasshoppers from the sky islands of the Rocky Mountains. Because this region was directly impacted by Pleistocene glaciation, both the displacement into glacial refugia and recolonization of montane habitats may contribute to differentiation. Building on the tradition of using information from the genealogical relationships of alleles to infer the geography of divergence, here the additional consideration of the process of gene-lineage sorting is used to obtain a quantitative estimate of population relationships and historical associations (i.e., a population tree) from the gene trees of five anonymous nuclear loci and one mitochondrial locus in the broadly distributed species Melanoplus oregonensis. Three different approaches are used to estimate a model of population divergence; this comparison allows us to evaluate specific methodological assumptions that influence the estimated history of divergence. A model of population divergence was identified that significantly fits the data better compared to the other approaches, based on per-site likelihood scores of the multiple loci, and that provides clues about how divergence proceeded in M. oregonensis during the dynamic Pleistocene. Unlike the approaches that either considered only the most recent coalescence (i.e., information from a single individual per population) or did not consider the pattern of coalescence in the gene genealogies, the population-divergence model that best fits the data was estimated by considering the pattern of gene lineage coalescence across multiple individuals, as well as loci. These results indicate that sampling of multiple individuals per population is critical to obtaining an accurate estimate of the history of divergence so that the signal of common ancestry can be separated from the confounding influence of gene flow,even though estimates suggest that gene flow is not a predominant factor structuring patterns of genetic variation across these sky island populations. They also suggest that the gene genealogies contain information about population relationships, despite the lack of complete sorting of gene lineages. What emerges from the analyses is a model of population divergence that incorporates both contemporary distributions and historical associations, and shows a latitudinal and regional structuring of populations reminiscent of population displacements into multiple glacial refugia. Because the population-divergence model itself is built upon the specific events shaping the history of M. oregonensis, it provides a framework for estimating additional population-genetic parameters relevant to understanding the processes governing differentiation in geographically structured species and avoids the problems of relying on overly simplified and inaccurate divergence models. The utility of these approaches, as well as the caveats and future improvements, for estimating population relationships and historical associations relevant to genetic analyses of geographically structured species are discussed. [source] Analysis of recent incidents of on-field violence in sport: legal decisions and additional considerations from psychologyAGGRESSIVE BEHAVIOR, Issue 1 2009John H. Kerr Abstract This article focuses on two recent incidents of serious on-field violence in sports and the legal consequences for those involved. The two incidents occurred in Dutch football (soccer) and became infamous owing to the nature of the violent incidents and widespread media coverage. The legal outcomes of these two incidents are described, and some of the difficulties that legal authorities face in considering assaults on the sports field are discussed. A new way of categorizing such violent incidents and the motivation behind them, based on an established psychological theory [reversal theory, Apter, 1982, 2001] is proposed. Taken along with the other points made in this article, being aware of when and how individuals cross the boundaries between play and anger, power or thrill violence may provide an additional perspective to making informed decisions about illegal violent acts on the sports field. Aggr. Behav. 35:41,48. 2009. © 2008 Wiley-Liss, Inc. [source] Issues in the Drive to Measure Liabilities at Fair ValueAUSTRALIAN ACCOUNTING REVIEW, Issue 21 2000MICHAEL E. BRADBURY This paper compares the discussion on liability measurement in Accounting The0y Monograph 10 with the liability measurement requirements in recent international proposals on accounting for financial instruments. Rather than conducting a detailed review of the Monograph, the paper examines three major issues which wawant amplifjing, extending or criticising: What is "fair value"? Why fair value liabilities? Should fair value include an entity's own credit risk? The focus is on financial liabilities such as "plain vanilla" debt; other financial liabilities, such as insurance obligations, pensions, wawanties and environmental damage restoration involve additional considerations and are therefore not considered. [source] | ||||||||||||||||