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Current Regime (current + regime)
Selected AbstractsMigration of landlocked brown trout in two Scandinavian streams as revealed from trap dataECOLOGY OF FRESHWATER FISH, Issue 3 2004J. Carlsson Abstract,,, Anthropogenic barriers that may interfere or prevent fish migration are commonly found in streams throughout the distribution of salmonids. Construction of fish passages in streams is a common solution to this problem. However, the goal with fish passages is often, at least in Scandinavia, to allow Atlantic salmon (Salmo salar L.) and migratory brown trout (S. trutta L.) to get access to spawning areas above these barriers. Hence, the fish passages may often only be open during the spawning migration of salmonids (late summer to autumn). We present data, on wild brown trout migration, from two trapping systems in two Scandinavian streams showing that intra- and interstream migrations are common throughout the summer and autumn. Moreover, differences in size were found between trap-caught trout and electrofished trout where trapped trout were generally larger than electrofished trout. We suggest that the current regime with fish passages only open parts of the year can have negative effects on populations by depriving trout from the possibility to perform migrations throughout the year. Resumen 1. Barreras de origin antrópico que pueden interferer o prevenir las migraciones de los peces son frecuentes a lo largo de las áreas de distribución de los salmónidos. Una solución común a este problema es la construcción de pasos. Si embargo, el fin general de estos pasos es, por lo menos en Escandinavia, permitir el acceso a las áreas de reproducción por encima de las barreras tanto a salmones (Salmo salar L.) como a truchas migratorias (S. trutta L.). Frecuentemente, estos pasos están solamente abiertos durante el período de migración reproductiva (final del verano y otoño) porque se piensa que este régimen no tiene consecuencias negativas ya que estas especies muestran movimientos muy limitados en otros periodos del año. 2. Presentamos datos sobre migraciones de truchas colectados en dos sistemas de trampas de dos ríos escandinavos. Un río localizado por encima de una catarata inaccesible. El segundo, con una población migratoria de truchas. Los datos indicaron claramente migraciones intensivas a lo largo de todo el período en el que las trampas estuvieron operativas. Ambos ríos mostraron un pico de migración aguas arriba a mediados de Julio. Migraciones aguas abajo fueron raramente observadas en la población por encima de la catarata aunque migraciones aguas abajo en la población del río fueron intensivas al final del otoño. 3. Sugerimos que el régimen actual de pasos de peces que abren solamente partes del año puede tener efectos negativos sobre las poblaciones, al privar a las truchas de la posibilidad de migrar a lo largo del año. Esto puede extenderse a otros sistemas con barreras ya que observamos también migraciones intensivas en la población localizada por encima de la catarata. [source] Keeping up or Falling behind?FISCAL STUDIES, Issue 4 2008Poverty, Tax Uprating on Incomes, The Impact of Benefit D31; I38 Abstract Each year, the government decides how much to raise benefits and tax allowances. In the UK, the basis for these upratings is rarely debated, yet has major long-term consequences for the relative living standards of different groups as well as for the public finances. This paper considers the medium-term implications of present uprating policies, which vary across parameters of the tax,benefit system. Continuing these policies for 20 years, other things staying the same, would result in a near doubling of the child poverty rate alongside a substantial gain to the public finances. At the same time, pensioners are largely protected by the earnings indexation of pensioner benefits including, in time, the basic state pension. We show how difficult it will be to meet the UK child poverty targets unless the greater inequality inherent in the current regime for uprating payments and allowances is redressed. [source] CURRENT VARIABILITY SHAPES MORPHOLOGICAL COMPLEXITY IN COLONIAL STREAM DIATOMSJOURNAL OF PHYCOLOGY, Issue 2001Article first published online: 24 SEP 200 Passy, S. I.1,2 & Freehafer, D.2 1Department of Biology, Rensselaer Polytechnic Institute, Troy, NY 12180; 2US Geological Survey, 425 Jordan Rd., Troy, NY 12180-8349 USA On August 27, 1999 diatoms were sampled, and current velocity was measured at 81 locations on a regular square sampling grid in an unshaded, cobble-bottom reach of White Creek, NY. The grid had an extent of 16 m2, interval, the distance between neighboring sampling points, of 0.5 m, and grain size, the size of the elementary sampling unit, of 0.01 m2. Six of the seven dominant benthic diatoms were colonial forms, including Diatoma vulgaris, Fragilaria capucina, F. crotonensis, Gomphoneis minuta, Melosira varians, and Synedra ulna. Their morphology and distribution were investigated from the perspective of fractal geometry and stream ecology, respectively. Fractal dimension of diatom colonies, indicative of their shape complexity, ranged from 1.06 to 1.54, demonstrating vast morphological variation from simple geometric shapes to complex outlines. The relative abundance of the six diatoms was regressed against current regime, which ranged from 0.03 to 0.66 m, s -1. All regression models were significant at P < 0.05 and explained between 55% and 94% of the variation in diatom distribution. The diatom niche breadth, i.e. the amount of environmental variability a species can tolerate, was defined from these models and showed substantial variation, from 5 to 14. The regression model of fractal dimension against niche breadth was significant and explained 76% of colonial shape variation, revealing a strong relationship between diatom colonial complexity and habitat variability. This finding suggests that environmental variability could create highly complex colonial morphologies in benthic diatoms as an evo-lutionary strategy for survival in unpredictable environments. [source] People's Exit in North Korea: New Threat to Regime Stability?PACIFIC FOCUS, Issue 2 2010Kyung-Ae Park As suggested in a growing literature that securitizes the phenomenon of refugee migration and analyzes it as a national as well as a regional security issue, the growing number of North Korean border-crossers has far-reaching political implications for both North Korea and the international community. Studies have argued that refugees could contribute significantly to democratic change in their home countries by assisting and actively participating in the struggle of the domestic opposition, even sparking regime instability and eventual regime breakdown. Much of the North Korean refugee research has focused on the human rights issues faced by the refugees, but a largely unexplored area of the refugee research concerns the political consequences of the refugee flight for the current regime in Pyongyang. This article examines whether North Korean refugees are expected to play the role of political opposition in exile by raising the following four questions: (i) Are the refugees political dissidents? (ii) Are they a resourceful critical mass? (iii) Does exit always lead to regime instability? and (iv) Would China and South Korea encourage exile politics against the current North Korean regime? The article contends that the North Korean refugee community does not currently represent a critical mass that can trigger instability of the Pyongyang regime. Most of the North Korean refugees are not political dissidents, nor have they organized into any resourceful critical mass capable of generating a threat to their home country. In addition, people's exit does not necessarily destabilize the regime as it can sometimes yield a positive political effect by driving out dissidents' voices. Furthermore, several of the receiving countries, in particular, China and South Korea, would not encourage exile dissident movements against North Korea for fear of Pyongyang's collapse. The North Korean regime's stability does not seem to be threatened by the current refugee situation, although the potential of refugees becoming a critical threat should not be discounted should people's exit ever reach the point of developing into an uncontrollable mass exodus. [source] Simulation of dc conductance of two-dimensional heterogeneous system: application to carbon wires made by ion irradiation on polycrystalline diamondPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 6 2006N. A. Poklonski Abstract A percolation model of two-dimensional heterogeneous system composed of two conductive phases and a method for calculating the macroscopic electric conductance of such a system in direct current regime is proposed. The parameters of the model are its geometrical dimensions, the conductance of the two phases and the relative fractions of the phases in the system. The model satisfactorily describes the non-linear dependence on width of conductance of the carbon nano- and microwires made on polycrystalline diamond surface by focused ion beam irradiation. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Entry and regulation: evidence from health care professionsTHE RAND JOURNAL OF ECONOMICS, Issue 4 2008Catherine Schaumans In many countries, pharmacies receive high regulated markups and are protected from competition through geographic entry restrictions. We develop an empirical entry model for pharmacies and physicians with two features: entry restrictions and strategic complementarities. We find that the entry restrictions have directly reduced the number of pharmacies by more than 50%, and also indirectly reduced the number of physicians by about 7%. A removal of the entry restrictions, combined with a reduction in the regulated markups, would generate a large shift in rents to consumers, without reducing the availability of pharmacies. The public interest motivation for the current regime therefore has no empirical support. [source] A modified HICUM model for GaInP/GaAs HBT devicesMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 4 2006S.-C. Tseng Abstract A compact physics-based transit-time model is established for the GaInP/GaAs HBT device. The VBIC model fails to describe the transit-time frequency versus bias (IC, VCE), especially at low- and medium-current regimes. Starting with the HICUM model, we introduce a new time constant to describe the transit-time frequency versus bias (IC, VCE) more precisely. This model has obvious advantages over the VBIC model for showing the relation of ft versus bias (IC, VCE) in the low and medium current regimes for GaInP/GaAs HBT devices. © 2006 Wiley Periodicals, Inc. Microwave Opt Technol Lett 48: 780,783, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21474 [source] | |||||||||||||