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Substantial Implications (substantial + implication)
Selected AbstractsRegime-dependent streamflow sensitivities to Pacific climate modes cross the Georgia,Puget transboundary ecoregionHYDROLOGICAL PROCESSES, Issue 24 2007Sean W. Fleming Abstract The Georgia Basin,Puget Sound Lowland region of British Columbia (Canada) and Washington State (USA) presents a crucial test in environmental management due to its combination of abundant salmonid habitat, rapid population growth and urbanization, and multiple national jurisdictions. It is also hydrologically complex and heterogeneous, containing at least three streamflow regimes: pluvial (rainfall-driven winter freshet), nival (melt-driven summer freshet), and hybrid (both winter and summer freshets), reflecting differing elevation ranges within various watersheds. We performed bootstrapped composite analyses of river discharge, air temperature, and precipitation data to assess El Niño,Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO) impacts upon annual hydrometeorological cycles across the study area. Canadian and American data were employed from a total of 21 hydrometric and four meteorological stations. The surface meteorological anomalies showed strong regional coherence. In contrast, the seasonal impacts of coherent modes of Pacific circulation variability were found to be fundamentally different between streamflow regimes. Thus, ENSO and PDO effects can vary from one stream to the next within this region, albeit in a systematic way. Furthermore, watershed glacial cover appeared to complicate such relationships locally; and an additional annual streamflow regime was identified that exhibits climatically driven non-linear phase transitions. The spatial heterogeneity of seasonal flow responses to climatic variability may have substantial implications to catchment-specific management and planning of water resources and hydroelectric power generation, and it may also have ecological consequences due to the matching or phase-locking of lotic and riparian biological activity and life cycles to the seasonal cycle. The results add to a growing body of literature suggesting that assessments of the streamflow impacts of ocean,atmosphere circulation modes must accommodate local hydrological characteristics and dynamics. Copyright © 2007 John Wiley & Sons, Ltd. The copyright in Paul H. Whitfield's contribution belongs to the Crown in right of Canada and such copyright material is reproduced with the permission of Environment Canada. [source] The Decline of America's Soft Power in the United Nations1INTERNATIONAL STUDIES PERSPECTIVES, Issue 3 2009Monti Narayan Datta To what extent does anti-Americanism precipitate a decline in America's soft power? Nye postulates a negative relationship, presenting substantial implications for the U.S. national interest. In this paper, I test Nye's hypothesis through an examination of America's political influence within the United Nations. Using a fixed effects model, I regress voting alignment within the UN General Assembly (UNGA) on cross-national, aggregate public opinion toward the United States from 1985 to 2007. Controlling for foreign aid received and alliances with the United States, I find a statistically significant, positive relationship between favorable attitudes toward the United States and voting alignment within the UNGA on overall plenary votes and those votes for which the U.S. lobbies other UN-member states extensively. At the same time, controlling for temporal effects, states are far less supportive of U.S. interests in the UN throughout the tenure of President George W. Bush, capturing the effect of "anti-Bushism" in addition to anti-Americanism. The results of this study shed light on an emerging area of the literature that not only studies the sources of anti-Americanism, but also its consequences. [source] Habitat heterogeneity influences connectivity in a spatially structured pest populationJOURNAL OF APPLIED ECOLOGY, Issue 2 2006G. S. HAMILTON Summary 1Patterns of connectivity influence pest population system dynamics, and it is essential to consider connectivity when planning effective management strategies. Traditional connectivity models often consider populations embedded in a matrix of unsuitable habitat. This approach is unlikely to be applicable to those pest species that can utilize most of the landscape in which they live. There is therefore a need for a simple and flexible tool to assess connectivity in such systems. 2In this study, we developed a new model in which contiguous resource patches that differ in quality, and landscape elements that impede dispersal, impact on connectivity within a population system. The model was applied to a wild rabbit population system, a well-studied pest species in Australia. An independent population genetic data set was used to validate the model. 3There was a highly significant association between pairwise population connectivity and the genetic data (Mantel test, r=,0·502, P= 0·002). As predicted, two populations that showed very low connectivity were strongly isolated genetically. These sites appeared to be substantially isolated because of forests, which acted to impede rabbit dispersal. When these sites were excluded from analysis, connectivity indices again explained the pattern of genetic data (Mantel test, r=,0·46, P= 0·037). This showed that both spatial variation in resource quality and forests influenced connectivity in this system. Sensitivity analyses confirmed that the distribution and extent of forests was important in limiting connectivity to some sites. The model was relatively robust to changes in population parameters. 4Synthesis and applications. Connectivity among wild rabbit populations in this system was strongly influenced by habitat heterogeneity, rather than factors such as geographical distance or major landscape elements such as rivers, both of which are traditionally considered to influence system dynamics. This may have substantial implications for many pest systems, and suggests that the impact of habitat heterogeneity on connectivity should be considered when planning efficient management strategies. [source] The implications of differences between employer and worker employment/earnings reports for policy evaluationJOURNAL OF POLICY ANALYSIS AND MANAGEMENT, Issue 4 2007Geoffrey L. Wallace Differences in administrative (UI) and survey (S) records on employment and earnings have substantial implications for assessing the impact of a variety of public interventions, such as welfare-to-work and employment training programs, and especially the state-oriented welfare reform legislation of 1996. We use data from the 1998 and 1999 waves of the Child Support Demonstration Evaluation (CSDE) Resident Parent Surveys to explore individual differences between survey and UI employment and earnings reports for a Wisconsin sample of current and former welfare recipients. After exploring the potential causes of misreports from both sources, we document the degree of discrepancy between survey and UI earnings and employment measures and assess the difference between the two earnings measures in estimates of simple human capital (earnings) functions. Last, we evaluate the correspondence of the two measures with "hardship" indicators of economic well-being. [source] Simulation and extremal analysis of hurricane eventsJOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES C (APPLIED STATISTICS), Issue 3 2000E. Casson In regions affected by tropical storms the damage caused by hurricane winds can be catastrophic. Consequently, accurate estimates of hurricane activity in such regions are vital. Unfortunately, the severity of events means that wind speed data are scarce and unreliable, even by standards which are usual for extreme value analysis. In contrast, records of atmospheric pressures are more complete. This suggests a two-stage approach: the development of a model describing spatiotemporal patterns of wind field behaviour for hurricane events; then the simulation of such events, using meteorological climate models, to obtain a realization of associated wind speeds whose extremal characteristics are summarized. This is not a new idea, but we apply careful statistical modelling for each aspect of the model development and simulation, taking the Gulf and Atlantic coastlines of the USA as our study area. Moreover, we address for the first time the issue of spatial dependence in extremes of hurricane events, which we find to have substantial implications for regional risk assessments. [source] The K+,Cl, cotransporter KCC2 promotes GABAergic excitation in the mature rat hippocampusTHE JOURNAL OF PHYSIOLOGY, Issue 9 2010Tero Viitanen GABAergic excitatory [K+]o transients can be readily evoked in the mature rat hippocampus by intense activation of GABAA receptors (GABAARs). Here we show that these [K+]o responses induced by high-frequency stimulation or GABAA agonist application are generated by the neuronal K+,Cl, cotransporter KCC2 and that the transporter-mediated KCl extrusion is critically dependent on the bicarbonate-driven accumulation of Cl, in pyramidal neurons. The mechanism underlying GABAergic [K+]o transients was studied in CA1 stratum pyramidale using intracellular sharp microelectrodes and extracellular ion-sensitive microelectrodes. The evoked [K+]o transients, as well as the associated afterdischarges, were strongly suppressed by 0.5,1 mm furosemide, a KCl cotransport inhibitor. Importantly, the GABAAR-mediated intrapyramidal accumulation of Cl,, as measured by monitoring the reversal potential of fused IPSPs, was unaffected by the drug. It was further confirmed that the reduction in the [K+]o transients was not due to effects of furosemide on the Na+ -dependent K+ -Cl, cotransporter NKCC1 or on intraneuronal carbonic anhydrase activity. Blocking potassium channels by Ba2+ enhanced [K+]o transients whereas pyramidal cell depolarizations were attenuated in further agreement with a lack of contribution by channel-mediated K+ efflux. The key role of the GABAAR channel-mediated anion fluxes in the generation of the [K+]o transients was examined in experiments where bicarbonate was replaced with formate. This anion substitution had no significant effect on the rate of Cl, accumulation, [K+]o response or afterdischarges. Our findings reveal a novel excitatory mode of action of KCC2 that can have substantial implications for the role of GABAergic transmission during ictal epileptiform activity. [source] Regulation of bladder muscarinic receptor subtypes by experimental pathologiesAUTONOMIC & AUTACOID PHARMACOLOGY, Issue 3 2006M. R. Ruggieri Sr Summary 1 The M3 muscarinic receptor subtype is widely accepted as the receptor on smooth muscle cells that mediates cholinergic contraction of the normal urinary bladder and other smooth muscle tissues, however, we have found that the M2 receptor participates in contraction under certain abnormal conditions. The aim of this study was to determine the effects of various experimental pathologies on the muscarinic receptor subtype mediating urinary bladder contraction. 2 Experimental pathologies resulting in bladder hypertrophy (denervation and outlet obstruction) result in an up-regulation of bladder M2 receptors and a change in the receptor subtype mediating contraction from M3 towards M2. Preventing the denervation-induced bladder hypertrophy by urinary diversion prevents this shift in contractile phenotype indicating that hypertrophy is responsible as opposed to denervation per se. 3 The hypertrophy-induced increase in M2 receptor density and contractile response is accompanied by an increase in the tissue concentrations of mRNA coding for the M2 receptor subtype, however, M3 receptor protein density does not correlate with changes in M3 receptor tissue mRNA concentrations across different experimental pathologies. 4 This shift in contractile phenotype from M3 towards M2 subtype is also observed in aged male Sprague,Dawley rats but not females or either sex of the Fisher344 strain of rats. 5 Four repeated, sequential agonist concentration response curves also cause this shift in contractile phenotype in normal rat bladder strips in vitro, as evidenced by a decrease in the affinity of the M3 selective antagonist p -fluoro-hexahydro-sila-diphenidol (p -F-HHSiD). 6 A similar decrease in the contractile affinity of M3 selective antagonists (darifenacin and p -F-HHSiD) is also observed in bladder specimens from patients with neurogenic bladder as well as certain organ transplant donors. 7 It is concluded that although the M3 receptor subtype predominately mediates contraction under normal circumstances, the M2 receptor subtype can take over a contractile role when the M3 subtype becomes inactivated by, for example, repeated agonist exposures or bladder hypertrophy. This finding has substantial implications for the clinical treatment of abnormal bladder contractions. [source] Truncated hemoglobins: trimming the classical ,three-over-three' globin fold to a minimal sizeBIOCHEMISTRY AND MOLECULAR BIOLOGY EDUCATION, Issue 3 2001Mario Milani Abstract Truncated hemoglobins (trHbs) host the heme in a ,two-over-two' ,-helical sandwich which results from extensive editing of the classical ,three-over-three' globin fold. The three-dimensional structure of trHbs is based on four main ,-helices, arranged in a sort of ,-helical bundle composed of two antiparallel helix pairs (B/E and G/H). Most notably, trHbs deviate from the conventional globin fold in that they display an extended loop substituting for the heme proximal F-helix observed in globins. Moreover, since efficient adaptation of a 110,130 amino acid trHb chain to host the porphyrin ring firstly requires specific chain flexibility, trHbs contain three invariant Gly-based motifs. Inspection of the trHb three-dimensional trHb structures shows that an apparent protein cavity or tunnel would connect the protein surface to an inner region very close to the heme distal site. Such a structural feature, never observed before in (non) vertebrate globins, may have substantial implications for ligand diffusion and binding properties in trHbs. © 2001 IUBMB. Published by Elsevier Science Ltd. All rights reserved. [source] The need and total cost of Finnish eyecare services: a simulation model for 2005,2040ACTA OPHTHALMOLOGICA, Issue 8 2009Anja Tuulonen Abstract. Purpose:, The aims of this study were: (i) to create a structural simulation model capable of predicting the future need and cost of eyecare services in Finland; and (ii) to test and rank different policy alternatives for access to care and the required physician workforce. Methods:, Using the system dynamics approach, the number and cost of patients with cataract, glaucoma, diabetic retinopathy and age-related macular degeneration (AMD) were described with causal-loop diagrams and were then translated into a set of mathematical equations to build a computer simulation model. Mathematically, the problem was formulated as a set of differential equations that were solved numerically with specialized software. The validity of the model was tested against prevalence and administrative historical data. The costs covered by the public sector in Finland were obtained from 2003 from the Finnish Hospital Discharge Register (including outpatient care), the Finnish Social Insurance Institution and a survey of hospital price lists. Different levels of access to public care were then simulated in four eye diseases, for which the model estimated the need for services and resources and their costs in the years 2005,2040. Results:, The model forecasted that the adoption of the 2005 national ,access to care' criteria for cataract surgery would shorten waiting lists. If the workload of Finnish ophthalmologists were kept at the 2003 level, the graduation rate of new ophthalmologists would have to increase by 75% from the current level. If all glaucoma patients were followed in the public sector in future, even this increase in training would not meet the demand for physician workforce. The current model indicated that the screening frequency of diabetes can be increased without large sacrifices in terms of costs. AMD therapy has a significant role in the allocation of future resources in eyecare. The modelling study predicted that ageing alone will increase the costs of eyecare during the next four decades in Finland by about 1% per year in real terms (undiscounted and without inflation of unit costs). The increases in total yearly costs were on average 8.6% between 2001 and 2003. Conclusions:, The results of this modelling study indicate that policy initiatives, such as defining criteria for access to care, can have substantial implications on the demand for care and waiting times whereas the effect of ageing alone was relatively small. Measures to control several other factors , such as the adoption and price level of new technologies, treatments and practice patterns , will be at least equally important in order to restrain healthcare costs effectively. [source] | |||||||||||||