Analyzing female labor supply: Evidence from a Dutch tax reform

This paper uses the exogenous variation caused by the Dutch tax reform of 2001 to investigate how married women react to financial incentives. Among OECD countries, the Netherlands has average female labor force participation, but by far the highest rate of part-time work. Our main conclusion is that the positive significant effect of the 2001 tax reform on labor force participation dominates the negative insignificant effect on working hours. Our preferred explanation is that women respond more to changes in tax allowances than to changes in marginal tax rates.

The influence of arginine supplementation on performance and metabolism in athletes

Objective: The aim of this review was to investigate the effects of supplementation with arginine, mainly in combination with aspartate and/or other potentially ergogenic amino acids, on metabolism of substrates, endocrine parameters and performance in endurance and resistance athletes. Data sources: The database PUBMED was consulted, using the following keywords "arginine", "aspartate", "performance" and "metabolism". The references in these articles were scanned for further relevant publications. Study section: Studies with oral or intravenous administration of arginine and/or aspartate alone or in combination with other amino acids were selected. Data extraction: Studies with at least six subjects and utilising a placebo-controlled design were analysed. Data synthesis: Seven studies with the combination of arginine aspartate and evaluation of the effect on performance in athletes were found and evaluated. In addition, further studies with arginine and combination with other amino acids were found and analysed in the same manner. Conclusions: No effect on selected parameters of metabolism or the endocrine system have been shown after oral or intravenous arginine, arginine aspartate or other combinations with arginine and aspartate. Neither were there any ergogenic effects in trained athletes after oral or intravenous arginine use, either alone or in combination with aspartate and/or other potentially ergogenic amino acids

FARM ADVISORY SERVICES AND PESTICIDE TOXICITY ON COTTON AND PEANUTS IN THE ALBEMARLE-PAMLICO WATERSHED

According to a Virginia-North Carolina watershed survey, farmers view advisory services as having the effect of decreasing pesticide use. However, analysis of pesticide use shows that hired staff, scouting personnel, and extension agents are associated with higher pesticide toxicity applied to cotton while chemical dealers and scouting personnel are associated with higher toxicity applied to peanuts.Crop Production/Industries, Environmental Economics and Policy,

Motivic Serre invariants, ramification, and the analytic Milnor fiber

We show how formal and rigid geometry can be used in the theory of complex singularities, and in particular in the study of the Milnor fibration and the motivic zeta function. We introduce the so-called analytic Milnor fiber associated to the germ of a morphism f from a smooth complex algebraic variety X to the affine line. This analytic Milnor fiber is a smooth rigid variety over the field of Laurent series C((t)). Its etale cohomology coincides with the singular cohomology of the classical topological Milnor fiber of f; the monodromy transformation is given by the Galois action. Moreover, the points on the analytic Milnor fiber are closely related to the motivic zeta function of f, and the arc space of X. We show how the motivic zeta function can be recovered as some kind of Weil zeta function of the formal completion of X along the special fiber of f, and we establish a corresponding Grothendieck trace formula, which relates, in particular, the rational points on the analytic Milnor fiber over finite extensions of C((t)), to the Galois action on its etale cohomology. The general observation is that the arithmetic properties of the analytic Milnor fiber reflect the structure of the singularity of the germ f.Comment: Some minor errors corrected. The original publication is available at http://www.springerlink.co

Yield Reserve Program Costs in the Virginia Coastal Plain

A proposed Yield Reserve Program designed to compensate farmers for any reduced yields resulting from nitrogen (N) application rates reduced to below recommended rates is evaluated. Assuming that farmers currently follow Extension recommendations for applying N, Yield Reserve Program participation reduces expected net revenue by $10 to$13/ha. The Yield Reserve Program reduces expected net revenue by $17 to$20/ha for farmers who apply N to maximize expected net revenue. Farmers’ costs of participation increase with lower probabilities of inadequate rainfall and higher corn prices and decline with higher N prices. The Yield Reserve Program can significantly reduce N applications to cropland, which may reduce N content of surface waters, but the costs to taxpayers and farmers will depend on how the program is implemented.compliance cost, nitrogen fertilizer, nonpoint source pollution, policy, yield response function, Agricultural and Food Policy, Crop Production/Industries,

Nicknames as sex-role stereotypes

Nicknames are powerful indicators of attitudes towards gender categories and because of their transient and optional nature, it has been argued that they are more likely to show a closer relationship to ongoing trends in the culture and society than other more fixed parts of the language E. B. Phillips (1990) ["Nicknames and Sex Role Stereotypes," Sex Roles, Vol. 23, pp. 281-289]. This study reports on a survey of nickname usage among a group of South African adolescents from mixed socioeconomic backgrounds (approximately 25% other than white) in an attempt to explicate gender-linked trends in frequency of occurrence, usage and attitudes to such special names. It reveals that conventions regarding nickname coinage and usage are intimately connected to the gender of bearers and users, and that more males have nicknames and coin them than females; it also shows significant sex-linked differences in the linguistic sources and users of nicknames, and reveals a greater tendency for female nicknames to function as indicators of affection rather than for humorous or critical effect. It could be argued that these trends could be linked to the nurturing and nurtured role of females in society, and to the differences in social power generally between males and females

Collective patterns arising out of spatio-temporal chaos

We present a simple mathematical model in which a time averaged pattern emerges out of spatio-temporal chaos as a result of the collective action of chaotic fluctuations. Our evolution equation possesses spatial translational symmetry under a periodic boundary condition. Thus the spatial inhomogeneity of the statistical state arises through a spontaneous symmetry breaking. The transition from a state of homogeneous spatio-temporal chaos to one exhibiting spatial order is explained by introducing a collective viscosity which relates the averaged pattern with a correlation of the fluctuations.Comment: 11 pages (Revtex) + 5 figures (postscript

The Expected Perimeter in Eden and Related Growth Processes

Following Richardson and using results of Kesten on First-passage percolation, we obtain an upper bound on the expected perimeter in an Eden Growth Process. Using results of the author from a problem in Statistical Mechanics, we show that the average perimeter of the lattice animals resulting from a very natural family of "growth histories" does not obey a similar bound.Comment: 11 page

Properties of Galaxy Groups in the SDSS: II.- AGN Feedback and Star Formation Truncation

Successfully reproducing the galaxy luminosity function and the bimodality in the galaxy distribution requires a mechanism that can truncate star formation in massive haloes. Current models of galaxy formation consider two such truncation mechanisms: strangulation, which acts on satellite galaxies, and AGN feedback, which predominantly affects central galaxies. The efficiencies of these processes set the blue fraction of galaxies as function of galaxy luminosity and halo mass. In this paper we use a galaxy group catalogue extracted from the Sloan Digital Sky Survey (SDSS) to determine these fractions. To demonstrate the potential power of this data as a benchmark for galaxy formation models, we compare the results to the semi-analytical model for galaxy formation of Croton et al. (2006). Although this model accurately fits the global statistics of the galaxy population, as well as the shape of the conditional luminosity function, there are significant discrepancies when the blue fraction of galaxies as a function of mass and luminosity is compared between the observations and the model. In particular, the model predicts (i) too many faint satellite galaxies in massive haloes, (ii) a blue fraction of satellites that is much too low, and (iii) a blue fraction of centrals that is too high and with an inverted luminosity dependence. In the same order, we argue that these discrepancies owe to (i) the neglect of tidal stripping in the semi-analytical model, (ii) the oversimplified treatment of strangulation, and (iii) improper modeling of dust extinction and/or AGN feedback. The data presented here will prove useful to test and calibrate future models of galaxy formation and in particular to discriminate between various models for AGN feedback and other star formation truncation mechanisms.Comment: 16 pages, 5 figures, submitted to MNRA