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Spillovers
Kinds of Spillovers Terms modified by Spillovers Selected AbstractsINTERREGIONAL KNOWLEDGE SPILLOVERS AND OCCUPATIONAL CHOICE IN A MODEL OF FREE TRADE AND ENDOGENOUS GROWTH,JOURNAL OF REGIONAL SCIENCE, Issue 5 2009Colin R. Davis ABSTRACT A two region model of horizontal innovation with free trade and occupational choice is used to examine the spatial patterns of innovation and manufacturing industry in interior and core-periphery long-run equilibria. The inclusion of skill heterogeneity among workers creates a tension between stabilizing productivity effects that coincide with reallocations of workers across industries, and destabilizing productivity effects that arise with localized stocks of knowledge capital. We find that while core-periphery equilibria are always saddlepath stable, interior equilibria are saddlepath stable when knowledge spillovers exceed a threshold level but are unstable otherwise. In addition, incorporating skill heterogeneity into the model allows for interior equilibria with asymmetric shares for innovation and industry. [source] R&D COMPETITION AND ENDOGENOUS SPILLOVERSTHE MANCHESTER SCHOOL, Issue 1 2006JIM Y. JIN The paper examines firms' choices between innovation and imitation in duopoly. We show that in the unique equilibrium asymmetric firms choose the same level of expenditure on imitation and the same ratio of innovative cost reduction to output. We evaluate the marginal contribution of innovation and imitation expenditure by small and large firms to consumer surplus and welfare, and discuss the desirability of differentiated R&D subsidies on innovation and imitation in terms of R&D tax rebates. [source] Financial Restatements, Cost of Debt and Information Spillover: Evidence From the Secondary Loan MarketJOURNAL OF BUSINESS FINANCE & ACCOUNTING, Issue 9-10 2009Jong Chool Park Abstract:, In this paper, we investigate the effect of financial restatements on the debt market. Specifically, we focus on the secondary loan market, which has become one of the largest capital markets in the US, and ask the following: (1) whether financial restatements increase restating firm's cost of debt financing and (2) whether the information about restatements arrives at the secondary loan market earlier than at the stock market? Using 176 restatement data, we find significant negative abnormal loan returns and increased bid-ask spreads around restatement announcements. Furthermore, this negative loan market reaction is more pronounced when the restatement is initiated by either the SEC or auditors, and when the primary reason for restatement is related to revenue recognition issues. Additionally, we find restatement information arrives at the secondary loan market earlier than at the equity market, and that such private information quickly flows into the equity market. We also show that stock prices begin to decline approximately 30 days prior to the restatement announcements for firms with traded loans. However, we do not find such informational leakage for firms without traded loans. Collectively, the results of this paper suggest: (1) increased cost of debt financing after restatements and (2) superior informational efficiency of the secondary loan market to the stock market. [source] Gender, Work, and Intimate Violence: Men's Occupational Violence Spillover and Compensatory ViolenceJOURNAL OF MARRIAGE AND FAMILY, Issue 4 2002Scott A. Melzer Researchers have rarely studied the effects of occupations on intimate violence, only occasionally distinguishing between blue-collar and white-collar work, and generally finding higher rates of reported abuse in the former group. This research incorporates ideas from feminist, work-family, and power or resource theories to examine the potential effects of occupations on men's violence toward wives and cohabiting female partners. Data from the 1988 National Survey of Families and Households (NSFH) were analyzed using logistic regression techniques. Hypotheses related to occupational spillover and compensation were tested with results suggesting that men in physically violent, female-dominated, professional specialty, and dangerous occupations are more likely to use violence against female partners, net of other commonly hypothesized predictors. The findings suggest that more detailed occupational data should be collected in future intimate violence research. [source] Reverse Hydrogen Spillover in Supported Subnanosize Clusters of the Metals of Groups 8 to 11.CHEMINFORM, Issue 9 2006A Computational Model Study. Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] Knowledge Spillovers and Knowledge Management , Charlie Karlsson, Per Flensburg and Sven-Ake HörteCREATIVITY AND INNOVATION MANAGEMENT, Issue 4 2006Jeroen Kraaijenbrink No abstract is available for this article. [source] Competition Among Banks, Capital Requirements and International SpilloversECONOMIC NOTES, Issue 3 2001Viral V. Acharya The design of prudential bank capital requirements interacts with the industrial organization of the banking sector, in particular, with the level of competition among banks. Increased competition leads to excessive risk-taking by banks which may have to be counteracted by tighter capital requirements. When capital requirements are internationally uniform but the levels of competition among banks in different countries are not, international spillovers arise on financial integration of these countries. This result begs a more careful analysis of the effect of financial liberalization on the stability of banking sectors in emerging countries. It also calls into question the merits of employing uniform capital requirements across countries that diverge in the industrial organization of their banking sectors. (J.E.L.: G21, G28, G38, F36, E58, D62) [source] Spillovers and Local Growth Controls: An Alternative Perspective on SuburbanizationGROWTH AND CHANGE, Issue 2 2005PILLSUNG BYUN ABSTRACT Since the 1970s, many local jurisdictions in politically fragmented metropolitan regions have enacted growth control and management measures to tackle the challenges arising from rapid suburban growth. These locally implemented growth controls have produced spillovers,the spatial shifts of homebuilding and households to nearby localities. Using data for California, this paper investigates the link between growth controls and homebuilding. The results suggest that some of the excess homebuilding can be linked to the presence or absence of growth control measures and thus be attributed to spillover effects. Moreover, generators of spillovers are nearly exclusively located in urban areas along the coast whereas the receptors of spillovers are primarily found at the metropolitan fringes and in peripherally located jurisdictions of the interior. [source] Research And Development Productivity And Spillovers: Empirical Evidence At The Firm LevelJOURNAL OF ECONOMIC SURVEYS, Issue 4 2005Robert Wieser Abstract., A variety of methods have been used to investigate the empirical relationship between research and development (R&D) spending and the productivity of firms. The most widely employed frameworks are the production function and the associated productivity framework. In these settings, productivity growth is related to expenditures on R&D, and an attempt is made to estimate statistically the part of productivity growth that can be attributed to R&D activities. This article surveys the expansive body of empirical literature on this subject and finds a large and significant impact of R&D on firm performance on average. However, the estimated returns vary considerably between the different studies due to differences across data samples and econometric models, as well as methodological and conceptual issues. A meta-analysis on the studies surveyed reveals that the estimated rates of return do not significantly differ between countries, whereas the estimated elasticities do. Furthermore, the estimated elasticities are significantly higher in the 1980s and consistently higher in the 1990s compared with the 1970s. Hence, contrary to a widely held belief, we find no convincing evidence of an exhaustion of R&D opportunities in the last two decades. [source] Knowledge Spillovers and Growth in the Disagglomeration of the Us Advertising-Agency IndustryJOURNAL OF ECONOMICS & MANAGEMENT STRATEGY, Issue 3 2003Charles King III We investigate knowledge spillovers and externalities in the disagglomeration and growth of the advertising-agency industry. A simple model of high demand, low wages, and externalities associated with clusters of related industries can explain the dispersion of advertising agency employment across states. Other factors affected the industry growth rate within states. Consistent with Jacobs and Porter but contrary to Marshall, Arrow, and Romer, competition, but not specialization, enhanced growth. In accord with Porter (1990), growth increased with buyer cluster size. Diversity had no effect on growth. Despite improvements in telecommunications and transportation reducing effective distances, location still matters. [source] Entrepreneurial Access and Absorption of Knowledge Spillovers: Strategic Board and Managerial Composition for Competitive AdvantageJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 2 2006David B. Audretsch The resource theory of the firm implies that knowledge is a key resource bestowing a competitive advantage for entrepreneurial firms. However, it remains rather unclear up to now how new ventures and small businesses can access knowledge resources. The purpose of this study was to suggest two strategies, in particular, that facilitate entrepreneurial access to and absorption of external knowledge spillovers: the attraction of managers and directors with an academic background. Based on data on board composition of 295 high-technology firms, the results clearly demonstrate the strong link between geographical proximity to research-intense universities and board composition. [source] Human Capital Spillovers within the Workplace: Evidence for Great Britain,OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 5 2003Harminder Battu Abstract In this paper, we use a unique matched worker,workplace data set to estimate the effect on own earnings of co-workers' education. Our results, using the 1998 GB Workplace Employee Relations Survey, show significant effects. An independent, significantly positive effect from average workplace education is evident; own earnings premia from years of education fall only slightly when controlling for workplace education. This result suggests that the social returns to education are strongly positive , working with colleagues who each had 1.2 years (1 standard deviation) of more education than the average worker, boosts own earnings by 11.1%. An additional year of any single co-worker's education is worth about 3.2% of an additional own year of education. We also test for interactions between own and co-worker education levels and for ,skills incompatibility' when worker education levels are heterogeneous. The interactions appear negative: own education is not much valued at workplaces where co-workers' education levels are already high. There is no evidence that workplace heterogeneity in worker education levels adversely affects own earnings. This result runs counter to theoretical predictions, and suggests that workers compete in tournaments for high-paying jobs. [source] Comovement After Joining an Index: Spillovers of Nonfundamental EffectsREAL ESTATE ECONOMICS, Issue 1 2007Brent W. Ambrose This study considers the case of two overlapping categories in the context of recent category models. Specifically, we examine whether investor sentiment and market frictions specific to one category can affect the returns on assets belonging to the other category. With recent additions of several real estate investment trusts (REITs) into general stock market indices as a natural experiment, we find support for spillovers of such nonfundamental effects, as evidenced by the increased return correlation between REITs that remain outside the index and the index stocks. Further analysis reveals that market frictions play a greater role than investor sentiment. [source] Spillovers, Investment Incentives and the Property Rights Theory of the FirmTHE JOURNAL OF INDUSTRIAL ECONOMICS, Issue 2 2004David de Meza This paper examines the property rights theory of the firm when a manager's relationship-specific investment can be partially appropriated by the owner of an asset even if cooperation breaks down. The investments of non owners may then be devalued, but are seldom wholly lost to the owner. With such spillovers, the outside-option principle can be incorporated into the Grossman-Hart-Moore framework without implying that ownership demotivates. Enriched predictions on the determinants of integration emerge. [source] Research and Development, Regional Spillovers and the Location of Economic ActivitiesTHE MANCHESTER SCHOOL, Issue 4 2004Alberto Franco Pozzolo I present an endogenous growth model that studies the effects of local inter-industry and intra-industry knowledge spillovers in R&D on the allocation of economic activities between two regions. The equilibrium is the result of a tension between a centripetal force, the cost of transporting goods from one region to the other, and a centrifugal force, the cost increase associated with life in a more crowded area. The presence of local knowledge spillovers, which determines the concentration of the R&D activities within one region, also introduces a further centripetal force that makes a symmetric allocation of the economic activities impossible. The concentration of R&D fosters the equilibrium rate of growth of the economy with respect to the case of no-integration, by increasing the positive effect of local knowledge spillovers. Contrary to the findings of the majority of models in the new economic geography literature, within this framework a reduction in transport costs may be associated with a more even geographical distribution of economic activities. [source] Productivity Spillovers from FDI in Malaysian Manufacturing: Evidence from Micro-panel Data,ASIAN ECONOMIC JOURNAL, Issue 2 2009Noor Aini Khalifah C23; F23; L6 Using an establishment-level panel dataset for the Malaysian manufacturing industries for 2000,2004, we argue that differences in the proxies and degrees of foreign shareholdings in measuring foreign presence lead to opposite signs and/or significance of spillover effects. The results show significant evidence of positive productivity spillovers to local establishments in the same industry, based on a broad measure of foreign presence. However, there is no evidence of positive spillover when employment share is used as a proxy for foreign presence. Furthermore, significant negative spillover effects are related to higher employment shares of wholly foreign-owned establishments. Although there is no significant difference in labor productivity between wholly foreign-owned and locally-owned establishments, both majority and minority foreign-owned establishments have significantly lower levels of labor productivity than locally-owned establishments in Malaysia. [source] US Credit Crisis and Spillovers to AsiaASIAN ECONOMIC POLICY REVIEW, Issue 2 2009Morris GOLDSTEIN F41; F34; F31; F37 We review key highlights of the global credit crisis. We then consider how financial turmoil in the largest advanced economies might be transmitted to East Asia. The focus is on foreign trade links, international capital flows, currency market pressures and mismatches, financial sector fragilities, and countercyclical monetary and fiscal policy actions. We introduce a set of vulnerability indicators and explore whether an ordinal ranking of East Asian economies according to these vulnerability indicators seems to be related to the cross-country differences in estimated slowdowns of economic growth during the crisis. Finally, we discuss how Asian economies might encourage the adoption of a stronger regulatory and supervisory framework in the USA and whether some Asian economies and the USA might pursue a more "balanced" growth strategy after the crisis. [source] R&D Subsidies versus R&D Cooperation in a Duopoly with Spillovers and PollutionAUSTRALIAN ECONOMIC PAPERS, Issue 1 2002Emmanuel Petrakis We introduce pollution, as a by-product of production, into a non-tournament model of R&D with spillovers. Technology policy takes the form of either R&D subsidisation or pre-competitive R&D cooperation. We show that, when the emissions tax is exogenous, the optimal R&D subsidy can be negative, i.e. there should be a tax on R&D, depending on the extent of the appropriability problem and the degree of environmental damage. In a wide class of cases, depending on the parameter values, welfare in the case of R&D cooperation, is lower than welfare in the case of R&D subsidisation. [source] Potential of Marine Reserves to Cause Community-Wide Changes beyond Their BoundariesCONSERVATION BIOLOGY, Issue 2 2007PAOLO GUIDETTI arrecifes rocosos templados; cambios a nivel comunitario; cascadas tróficas; estados comunitarios alternativos; exceso de pesca; reservas marinas Abstract:,Fishing and other human activities can alter the abundances, size structure, and behavior of species playing key roles in shaping marine communities (e.g., keystone predators), which may in turn cause ecosystem shifts. Despite extensive evidence that cascading trophic interactions can underlie community-wide recovery inside no-take marine reserves by protecting high-level predators, the spatial extent of these effects into adjacent fished areas is unknown. I examined the potential for community-wide changes (i.e., the transition from overgrazed coralline barrens to macroalgal beds) in temperate rocky reefs within and around a no-take marine reserve. For this purpose I assessed distribution patterns of predatory fishes, sea urchins, and barrens across the reserve boundaries. Predatory fishes were significantly more abundant within the reserve than in adjacent locations, with moderate spillover across the reserve edges. In contrast, community-wide changes of benthic assemblages were apparent well beyond the reserve boundaries, which is consistent with temporary movements of predatory fishes (e.g., foraging migration) from the reserve to surrounding areas. My results suggest that no-take marine reserves can promote community-wide changes beyond their boundaries. Resumen:,La pesca y otras actividades humanas pueden alterar la abundancia, tamaño, estructura y comportamiento de las especies que juegan papeles clave en el modelado de las comunidades marinas (e.g., depredadores clave), que a su vez pueden causar cambios en los ecosistemas. No obstante la evidencia extensiva de que las interacciones tróficas en cascada pueden subyacer en la recuperación de la comunidad dentro de reservas marinas que no permiten la pesca mediante la protección de depredadores de nivel alto, se desconoce la extensión espacial de estos efectos en áreas adyacentes. Examiné el potencial de los cambios a nivel comunidad (i.e., la transición de áreas coralinas sobre pastoreadas a lechos de microalgas) en arrecifes rocosos templados dentro y alrededor de una reserva marina sin pesca. Para este propósito, evalué los patrones de distribución de peces depredadores, erizos de mar y áreas sobre pastoreadas en los límites de la reserva. Los peces depredadores fueron significativamente más abundantes dentro de la reserva que en localidades adyacentes, con un excedente moderado en los bordes de la reserva. En contraste, los cambios a nivel de comunidad en los ensambles bénticos fueron aparentes más allá de los límites de la reserva, lo que es consistente con los movimientos temporales de los peces depredadores (e.g., migración de forrajeo) desde la reserva hacia las áreas circundantes. Mis resultados sugieren que las reservas que no permiten la pesca pueden promover cambios a nivel comunidad más allá de sus límites. [source] THE EFFECTS OF THE 1.03 MILLION YEN CEILING IN A DYNAMIC LABOR SUPPLY MODELCONTEMPORARY ECONOMIC POLICY, Issue 2 2009YUKIKO ABE In this paper I examine the effects of a means-tested transfer system in Japan ("1.03 million yen ceiling") in a dynamic labor supply model with endogenous retirement. In Japan, married women have reason to limit their annual earnings to no more than 1.03 million yen in order to receive a number of benefits available to low-income wives, and in fact often choose to do so. In a dynamic model, the optimal labor supply schedule follows a pattern that is not seen in a static framework, which I call the "spillover effect." The paper also examines the properties of dynamic welfare cost of this ceiling. (JEL J22, H24, H55) [source] Functions of glutamate transporters in cerebellar Purkinje cell synapsesACTA PHYSIOLOGICA, Issue 1 2009Y. Takayasu Abstract Glutamate transporters play a critical role in the maintenance of low extracellular concentrations of glutamate, which prevents the overactivation of post-synaptic glutamate receptors. Four distinct glutamate transporters, GLAST/EAAT1, GLT-1/EAAT2, EAAC1/EAAT3 and EAAT4, are distributed in the molecular layer of the cerebellum, especially near glutamatergic synapses in Purkinje cells (PCs). This review summarizes the current knowledge about the differential roles of these transporters at excitatory synapses of PCs. Data come predominantly from electrophysiological experiments in mutant mice that are deficient in each of these transporter genes. GLAST expressed in Bergmann glia contributes to the clearing of the majority of glutamate that floods out of the synaptic cleft immediately after transmitter release from the climbing fibre (CF) and parallel fibre (PF) terminals. It is indispensable to maintain a one-to-one relationship in synaptic transmission at the CF synapses by preventing transcellular glutamate spillover. GLT-1 plays a similar but minor role in the uptake of glutamate as GLAST. Although the loss of neither GLAST nor GLT-1 affects cerebellar morphology, the deletion of both GLAST and GLT-1 genes causes the death of the mutant animal and hinders the folium formation of the cerebellum. EAAT4 removes the low concentrations of glutamate that escape from uptake by glial transporters, preventing the transmitter from spilling over into neighbouring synapses. It also regulates the activation of metabotropic glutamate receptor 1 (mGluR1) in perisynaptic regions at PF synapses, which in turn affects mGluR1-mediated events including slow EPSCs and long-term depression. No change in synaptic function is detected in mice that are deficient in EAAC1. [source] Labor productivity of small and large manufacturing firms: the case of TaiwanCONTEMPORARY ECONOMIC POLICY, Issue 3 2000M. Hsu This work studies the factors influencing the labor productivity of small and medium-sized enterprises (SMEs) and large firms using Taiwan as a case study. A special emphasis is placed on two possible international channels: exports and foreign direct investment (FDI). Different from conventional studies, we employ the two-stage switching regressions to correct the firm-size effect on labor productivity and estimate labor productivity for SMEs and large firms. The main findings are as follows. First, the estimates of the selectivity variable are statistically significant for both SMEs and large firms, supporting the hypothesis of correcting the effect of firm-size truncation. Second, while a larger trade intensity significantly increases the labor productivity of SMEs, it deteriorates significantly that of large firms. Third, FDI enhances the labor productivity of SMEs internally, whereas it has a negative spillover on that of other small and large firms in the industry. While the first outcome lends supports to the role of self-selection, the remaining stands in sharp contrast to conventional wisdom. [source] Near-infrared dyes for six-color immunophenotyping by laser scanning cytometryCYTOMETRY, Issue 3 2002Andreas O.H. Gerstner Abstract Background To adequately analyze the complexity of the immune system and reduce the required sample volume for immunophenotyping in general, more measurable colors for the discrimination of leukocyte subsets are necessary. Immunophenotyping by the laser scanning cytometer (LSC), a slide-based cytometric technology, combines cell detection based on multiple colors with their subsequent visualization without the need for physical cell sorting. In the present study, the filter setting of the LSC was adapted for the measurement of the far-red emitting dye cyanine 7 (Cy7), thereby increasing the number of measurable commercially available fluorochromes. Methods The optical filters of the LSC were replaced,photomultiplier (PMT) 3/allophycocyanin (APC): 740-nm dichroic long pass, and 670-/55-nm bandpass; PMT 4/Cy7: 810-/90-nm bandpass. Peripheral blood leukocytes were stained directly by fluorochrome-labeled antibodies or by indirect staining. The tandem dyes of Cy7 (phycoerythrin [PE]-Cy7, APC-Cy7) and the fluorochromes fluorescein isothiocyanate (FITC), PE, PE-Cy5, and APC were tested alone and in different combinations. Results With the new filter combination and tandem fluorochromes, Cy7 was measurable at 488-nm (argon laser) or 633-nm (helium-neon laser) excitation. Resolution was in the range of FITC for PE-Cy7 but approximately 30% lower for APC-Cy7; spillover into the respective donor fluorochrome channel for both tandem dyes was prominent. A six-color panel for leukocyte subtyping was designed. Conclusions With this adaptation, it is possible to measure the tandem conjugates PE-Cy7 and APC-Cy7. This new setup opens the way for six-color immunophenotyping by LSC. Cytometry 48:115,123, 2002. © 2002 Wiley-Liss, Inc. [source] Spillover edge effects: the dispersal of agriculturally subsidized insect natural enemies into adjacent natural habitatsECOLOGY LETTERS, Issue 5 2006Tatyana A. Rand Abstract The cross-edge spillover of subsidized predators from anthropogenic to natural habitats is an important process affecting wildlife, especially bird, populations in fragmented landscapes. However, the importance of the spillover of insect natural enemies from agricultural to natural habitats is unknown, despite the abundance of studies examining movement in the opposite direction. Here, we synthesize studies from various ecological sub-disciplines to suggest that spillover of agriculturally subsidized insect natural enemies may be an important process affecting prey populations in natural habitat fragments. This contention is based on (1) the ubiquity of agricultural,natural edges in human dominated landscapes; (2) the substantial literature illustrating that crop and natural habitats share important insect predators; and (3) the clear importance of the landscape matrix, specifically distance to ecological edges, in influencing predator impacts in agroecosystems. Further support emerges from theory on the importance of cross-boundary subsidies for within site consumer,resource dynamics. In particular, high productivity and temporally variable resource abundance in agricultural systems are predicted to result in strong spillover effects. More empirical work examining the prevalence and significance of such natural enemy spillover will be critical to a broader understanding of fragmentation impacts on insect predator,prey interactions. [source] Pre- and postsynaptic GABAA receptors at reciprocal dendrodendritic synapses in the olfactory bulbEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 11 2004Patrizia Panzanelli Abstract Presynaptic ionotropic receptors are important regulators of synaptic function; however, little is known about their organization in the presynaptic membrane. We show here a different spatial organization of presynaptic and postsynaptic GABAA receptors at reciprocal dendrodendritic synapses between mitral and granule cells in the rat olfactory bulb. Using postembedding electron microscopy, we have found that mitral cell dendrites express GABAA receptors at postsynaptic specializations of symmetric (GABAergic) synapses, as well as at presynaptic sites of asymmetric (glutamatergic) synapses. Analysis of the subsynaptic distribution of gold particles revealed that in symmetric synapses GABAA receptors are distributed along the entire postsynaptic membrane, whereas in asymmetric synapses they are concentrated at the edge of the presynaptic specialization. To assess the specificity of immunogold labelling, we analysed the olfactory bulbs of mutant mice lacking the ,1 subunit of GABAA receptors. We found that in wild-type mice ,1 subunit immunoreactivity was similar to that observed in rats, whereas in knockout mice the immunolabelling was abolished. These results indicate that in mitral cell dendrites GABAA receptors are distributed in a perisynaptic domain that surrounds the presynaptic specialization. Such presynaptic receptors may be activated by spillover of GABA from adjacent inhibitory synapses and modulate glutamate release, thereby providing a novel mechanism regulating dendrodendritic inhibition in the olfactory bulb. [source] Region-specific changes in sympathetic nerve activity in angiotensin II,salt hypertension in the ratEXPERIMENTAL PHYSIOLOGY, Issue 1 2010John W. Osborn It is now well accepted that many forms of experimental hypertension and human essential hypertension are caused by increased activity of the sympathetic nervous system. However, the role of region-specific changes in sympathetic nerve activity (SNA) in the pathogenesis of hypertension has been difficult to determine because methods for chronic measurement of SNA in conscious animals have not been available. We have recently combined indirect, and continuous and chronic direct, assessment of region-specific SNA to characterize hypertension produced by administration of angiotensin II (Ang II) to rats consuming a high-salt diet (Ang II,salt hypertension). Angiotensin II increases whole-body noradrenaline (NA) spillover and depressor responses to ganglionic blockade in rats consuming a high-salt diet, but not in rats on a normal-salt diet. Despite this evidence for increased ,whole-body SNA' in Ang II,salt hypertensive rats, renal SNA is decreased in this model and renal denervation does not attenuate the steady-state level of arterial pressure. In addition, neither lumbar SNA, which largely targets skeletal muscle, nor hindlimb NA spillover is changed from control levels in Ang II,salt hypertensive rats. However, surgical denervation of the splanchnic vascular bed attenuates/abolishes the increase in arterial pressure and total peripheral resistance, as well as the decrease in vascular capacitance, observed in Ang II,salt hypertensive rats. We hypothesize that the ,sympathetic signature' of Ang II,salt hypertension is characterized by increased splanchnic SNA, no change in skeletal muscle SNA and decreased renal SNA, and this sympathetic signature creates unique haemodynamic changes capable of producing sustained hypertension. [source] Contagion Effects from the 1994 Mexican Peso Crisis: Evidence from Chilean StocksFINANCIAL REVIEW, Issue 1 2002Ike Mathur The contagion, or informational spillover, effects of the 1994 peso crisis from the Mexican market to the Chilean market, and to the Chilean American Depository Receipts (ADRs) trading in the U.S., are examined. Significant excess returns are observed for Chilean stocks for the event dates of the Mexican Peso crisis, providing evidence of contagion effects. Significant excess returns on these Chilean ADRs are also observed for each of the five event dates associated with the Peso crisis, suggesting that the contagion effects spilled over to the ADRs. A multiple regression model shows that the spillover contagion effects were very efficiently transmitted from the Mexican market to the Chilean market to the Chilean ADRs. Multifactor regressions show that the most significant influence on the pricing of Chilean ADRs is the raw Chilean Index, rather than the Chilean Index expressed in U.S. dollars. [source] How do individual transferable quotas affect marine ecosystems?FISH AND FISHERIES, Issue 1 2009Trevor A Branch Abstract Published papers were reviewed to assess ecosystem impacts of individual transferable quotas (ITQs) and other dedicated access systems. Under ITQs, quota shares increase with higher abundance levels, thus fishers may request lower total allowable catches (TACs) and pay for monitoring and research that improves fishery sustainability. Mortality on target species generally declines because catches are closer to TACs and because ghost fishing through lost and abandoned gear decreases. High-grading and discarding often decline, but may increase if landings (and not catches) count against ITQs and when there is little at-sea enforcement. Overall, ITQs positively impact target species, although collapses can occur if TACs are set too high or if catches are routinely allowed to exceed TACs. Fishing pressure may increase on non-ITQ species because of spillover from ITQ fisheries, and in cases where fishers anticipate that future ITQ allocations will be based on catch history and therefore increase their current catches. Ecosystem and habitat impacts of ITQs were only sparsely covered in the literature and were difficult to assess: ITQs often lead to changes in total fishing effort (both positive and negative), spatial shifts in effort, and fishing gear modifications. Stock assessments may be complicated by changes in the relationship between catch per unit effort, and abundance, but ITQ participants will often assist in improving data collection and stock assessments. Overall, ITQs have largely positive effects on target species, but mixed or unknown effects on non-target fisheries and the overall ecosystem. Favourable outcomes were linked to sustainable TACs and effective enforcement. [source] Glutamate spillover augments GABA synthesis and release from axodendritic synapses in rat hippocampusHIPPOCAMPUS, Issue 1 2010Misty M. Stafford Abstract Tight coupling between gamma-aminobutyric acid (GABA) synthesis and vesicle filling suggests that the presynaptic supply of precursor glutamate could dynamically regulate inhibitory synapses. Although the neuronal glutamate transporter excitatory amino acid transporter 3 (EAAT3) has been proposed to mediate such a metabolic role, highly efficient astrocytic uptake of synaptically released glutamate normally maintains low-extracellular glutamate levels. We examined whether axodendritic inhibitory synapses in stratum radiatum of hippocampal area CA1, which are closely positioned among excitatory glutamatergic synapses, are regulated by synaptic glutamate release via presynaptic uptake. Under conditions of spatially and temporally coordinated release of glutamate and GABA within pyramidal cell dendrites, blocking glial glutamate uptake enhanced quantal release of GABA in a transporter-dependent manner. These physiological findings correlated with immunohistochemical studies revealing expression of EAAT3 by interneurons and uptake of D-asparate into putative axodendritic inhibitory terminals only when glial uptake was blocked. These results indicate that spillover of glutamate between adjacent excitatory and inhibitory synapses can occur under conditions when glial uptake incompletely clears synaptically released glutamate. Our anatomical studies also suggest that perisomatic inhibitory synapses, unlike synapses within dendritic layers of hippocampus, are not capable of glutamate uptake and therefore transporter-mediated dynamic regulation of inhibition is a unique feature of axodendritic synapses that may play a role in maintaining a homeostatic balance of inhibition and excitation. © 2009 Wiley-Liss, Inc. [source] Gradualism, Transparency and the Improved Operational Framework: A Look at Overnight Volatility Transmission,INTERNATIONAL FINANCE, Issue 2 2009Silvio Colarossi This paper proposes a possible way of assessing the effect on interest rate dynamics of changes in the decision-making method, in the communication strategy and in the operational framework of a central bank. Through a generalized autoregressive conditional heteroscedasticity (GARCH) specification, we show that the United States and the euro area displayed a limited but significant spillover of volatility from money market to longer-term rates. We then checked the stability of this phenomenon in the most recent period of improved policy-making and found empirical evidence to show that the transmission of overnight volatility along the yield curve had entirely disappeared. [source] | |||||||||||||||||||||||||||||||||||||||||||