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Cyclical Fluctuations (cyclical + fluctuation)

Distribution by Scientific Domains

Business, Economics, Finance and Accounting	40%

Selected Abstracts

Oestrogenic Regulation Of Brain Angiotensinogen

JOURNAL OF NEUROENDOCRINOLOGY, Issue 6 2004
K. J. Greenland
Abstract Oestrogens are now recognized as playing a regulatory role on components of the systemic renin,angiotensin system, such as its precursor, angiotensinogen (AGT). In the brain, this role is poorly understood. The aim of this study was to investigate the influence of oestrogens on brain AGT of female rats at different stages of the oestrous cycle, in pregnancy and following ovariectomy with and without hormone replacement. AGT content of different brain regions was also studied in male rats treated with oestrogens. The brain was divided into five regions: cortex, cerebellum, brainstem, midbrain and thalamus/hypothalamus, and AGT was measured by direct radioimmunoassay using a highly specific AGT antibody. Cyclical fluctuations in AGT content were observed in all regions except the cerebellum over the course of the 4-day oestrous cycle, with peak concentrations at estrus and lowest concentrations at metestrus. Following ovariectomy, brain AGT was significantly decreased in the thalamic/hypothalamic region, an effect that was reversed by oestrogen-replacement. In pregnant rats, AGT contents were elevated in the brainstem region. Oestrogen treatment of male rats induced significant increases in AGT concentrations in all areas except the cortex. In summary, these results show that oestradiol has actions on brain AGT that are region-specific and dependent on the particular physiological and reproductive context. Moreover, the changes in AGT concentrations in the oestrous cycle suggest the involvement of other factors besides oestrogen. Finally, this study supports the view that the brain renin,angiotensin system has a broad role in oestrogen-modulated brain functions beyond those specific to the hypothalamic,pituitary,ovarian axis. [source]

Disability, capacity for work and the business cycle: an international perspective

ECONOMIC POLICY, Issue 63 2010
Hugo Benítez-Silva
Summary Important policy issues arise from the high and growing number of people claiming disability benefits for reasons of incapacity for work in OECD countries. Economic conditions play an important part in explaining both the stock of disability benefit claimants and inflows to and outflows from that stock. Employing a variety of cross-country and country-specific household panel data sets, as well as administrative data, we find strong evidence that local variations in unemployment have an important explanatory role for disability benefit receipt, with higher total enrolments, lower outflows from rolls and, often, higher inflows into disability rolls in regions and periods of above-average unemployment. In understanding the nature of the cyclical fluctuations and trends in disability it is important to distinguish between work disability and health disability. The former is likely to be influenced by economic conditions and welfare programmes while the latter evolves in a slower fashion with medical technology and demographic changes. There is little evidence of health disability being related to the business cycle, so cyclical variations are driven by work disability. The rise in unemployment due to the current global economic crisis is expected to increase the number of disability insurance claimants. --- Hugo Benítez-Silva, Richard Disney and Sergi Jiménez-Martín [source]

Relative contributions from exposed inshore and estuarine nursery grounds to the recruitment of stone flounder, Platichthys bicoloratus, estimated using otolith Sr:Ca ratios

FISHERIES OCEANOGRAPHY, Issue 4 2000
Yoh Yamashita
In Sendai Bay, stone flounder larvae settle and spend their juvenile period in either shallow exposed inshore nursery grounds or estuarine nursery grounds. The purpose of this study is to examine the relative contributions of these two kinds of nursery grounds to the flounder population using otolith strontium:calcium ratios. Stone flounder juveniles were collected from both nursery grounds, and one- and two-year-old flounder were caught deeper in Sendai Bay. Sr and Ca content in the otoliths were measured by electron probe micro analysis. The Sr:Ca ratios in the otolith section corresponding to the early postsettlement period ranged from 3.06 to 3.85 for the exposed inshore areas with stable low temperature and high salinity conditions, and from 3.81 to 5.32 in brackish estuaries with high temperature and low salinity conditions but with large diel and tidal cyclical fluctuations. Values from an estuarine site with stable salinity ranged from 3.58 to 4.15 overlapping with both the above ranges. Rearing experiments supported our inference that the high otolith Sr:Ca ratios of juveniles inhabiting estuarine nursery grounds are attributable to higher temperature and physiological stress caused by the large diel temperature and salinity fluctuations within the estuaries. Estimation of the Sr:Ca ratio of recruited fish using the otolith section formed while in the nursery area showed that at least 20 out of 42 individuals examined originated from estuarine nursery grounds. The present study indicates that estuaries play an important role as nursery grounds for stone flounder, producing about half of the stock in spite of the small and restricted area compared with the wide expanse of the exposed inshore area. [source]

Maastricht's Fiscal Rules at Ten: An Assessment

JCMS: JOURNAL OF COMMON MARKET STUDIES, Issue 5 2002
Marco Buti
The Maastricht Treaty is ten years old. Its fiscal rules played a key role in kickstarting and sustaining the budgetary retrenchment efforts in European Union countries in the run,up to economic and monetary union (EMU). The experience of the Maastricht,induced fiscal consolidation shows that the political economy dimension of the rules is key to their success. It remains to be seen whether the stability and growth pact , which aims to lock EMU members into a permanent fiscal discipline commitment while allowing for flexibility to cushion cyclical fluctuations , will work. In order to succeed in this undertaking, EU governments and institutions have to tackle a number of open issues in the implementation of the pact while recreating the political drive which made Maastricht a success. [source]

A Complete Decomposition of Unemployment Dynamics using Longitudinal Grouped Duration Data,

OXFORD BULLETIN OF ECONOMICS & STATISTICS, Issue 1 2005
Muriel Dejemeppe
Abstract In this paper, we study the unemployment dynamics in the Belgian regions, Flanders and Wallonia, on the basis of aggregate stratified data covering the period 1973,93. We decompose the aggregate exit probability from unemployment into calendar time and, both observed and unobserved, compositional effects. We find that changes in the inflow composition affect the cyclical fluctuations in unemployment duration only marginally. However, the long-run improvement in the quality of entrants into unemployment, notably in terms of educational attainment, mitigates the strong upward trend in this duration. This is a new result as none of the existing studies purges the trend in the aggregate outflow rate of the variation in its composition. We also conclude that in Belgium, incidence explains as much as 45% of the evolution of unemployment. Finally, the diverging evolution of unemployment across Flanders and Wallonia predominantly results from a stronger decline in the exit rates from unemployment in Wallonia. [source]