A variational formulation of relativistic hydrodynamics

We combine Taub's and Ray's variational approaches to relativistic hydrodynamics of perfect fluids into another simple formulation.Comment: 3 pages; published versio

Estimating Costs and Benefits Associated with Evidence-Based Violence Prevention: Four case studies based on the Fourth R program

Teen violence in dating and peer relationships has huge costs to society in numerous areas including health care, social services, the workforce and the justice system. Physical, psychological, and sexual abuse have long-lasting ramifications for the perpetrators as well as the victims, and for the families involved on both sides of that equation. An effective violence prevention program that is part of a school’s curriculum is beneficial not only for teaching teenagers what is appropriate behaviour in a relationship, but also for helping them break the cycle of violence which may have begun at home with their own maltreatment as children. The Fourth R program is an efficacious violence prevention program that was developed in Ontario and has been implemented in schools throughout Canada and the U.S. Covering relationship dynamics common to dating violence as well as substance abuse, peer violence and unsafe sex, the program can be adapted to different cultures and to same-sex relationships. The program, which gets its name from the traditional 3Rs — reading, ’riting and ’rithmetic — offers schools the opportunity to provide effective programming for teens to reduce the likelihood of them using relationship for violence as they move into adulthood. The federal government has estimated that the societal costs of relationship violence amount to more than $7 billion. These costs can continue to be incurred through the legal and health-care systems as the ripple effects of violence play out over the years, even after a relationship has ended. Other types of violence are also costly to society and not just in terms of dollars, but in young lives diverted into criminal activity. Up to 15 per cent of youth who become involved with the justice system grow into serious adult offenders who develop lengthy criminal careers. Yet, research shows that if prevention programs such as the Fourth R can deter just one 14-year-old high-risk juvenile from a life of crime, up to$5 million can be saved in costs to society

Analysis of high-speed continuous casting with inverse finite elements

A recently proposed inverse isotherm finite element method is further extended in order to account for processes with distorted isotherms. With this method a variety of problems can be solved which require the explicit calculation of characteristic material lines along with the common field of unknowns in transport phenomena. The method is applied to high-speed metal casting, where the location and shape of the extensive solidification front is calculated simultaneously with the primary unknowns, the velocity and the pressure, whereas the temperature is fixed at the moving nodes of the finite element tessellation. This is achieved by solving the energy equation inversely along with the rest of the conservation equations, i.e. the temperature field is fixed and its location is calculated. Empirical correlations may be derived which give the shape of the solidification front as a function of the process parameters. This may be used to improve the control means of metal casting, which is currently based on one-dimensional approximate analyses.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/50204/1/1650131002_ftp.pd

Galactic rotation curves and brane world models

In the present investigation flat rotational curves of the galaxies are considered under the framework of brane-world models where the 4d effective Einstein equation has extra terms which arise from the embedding of the 3-brane in the $5d$ bulk. It has been shown here that these long range bulk gravitational degrees of freedom can act as a mechanism to yield the observed galactic rotation curves without the need for dark matter. The present model has the advantage that the observed rotation curves result solely from well-established non-local effects of gravitation, such as dark radiation and dark pressure under a direct use of the condition of flat rotation curves and does not invoke any exotic matter field.Comment: 7 Latex pages, 7 figures; Edited substantially with new figures and references; Accepted for Mon. Not. R. Astron. So

Alcohol Sales and Risk of Serious Assault

In a population-based case-crossover analysis, Joel Ray and colleagues find that the risk of being a victim of serious assault increases with retail alcohol sales, especially among young urban men

Metabolomic, Transcriptional, Hormonal, and Signaling Cross-Talk in Superroot2

Auxin homeostasis is pivotal for normal plant growth and development. The superroot2 (sur2) mutant was initially isolated in a forward genetic screen for auxin overproducers, and SUR2 was suggested to control auxin conjugation and thereby regulate auxin homeostasis. However, the phenotype was not uniform and could not be described as a pure high auxin phenotype, indicating that knockout of CYP83B1 has multiple effects. Subsequently, SUR2 was identified as CYP83B1, a cytochrome P450 positioned at the metabolic branch point between auxin and indole glucosinolate metabolism. To investigate concomitant global alterations triggered by knockout of CYP83B1 and the countermeasures chosen by the mutant to cope with hormonal and metabolic imbalances, 10-day-old mutant seedlings were characterized with respect to their transcriptome and metabolome profiles. Here, we report a global analysis of the sur2 mutant by the use of a combined transcriptomic and metabolomic approach revealing pronounced effects on several metabolic grids including the intersection between secondary metabolism, cell wall turnover, hormone metabolism, and stress responses. Metabolic and transcriptional cross-talks in sur2 were found to be regulated by complex interactions between both positively and negatively acting transcription factors. The complex phenotype of sur2 may thus not only be assigned to elevated levels of auxin, but also to ethylene and abscisic acid responses as well as drought responses in the absence of a water deficiency. The delicate balance between these signals explains why minute changes in growth conditions may result in the non-uniform phenotype. The large phenotypic variation observed between and within the different surveys may be reconciled by the complex and intricate hormonal balances in sur2 seedlings decoded in this study