Parallel Implementation of the PHOENIX Generalized Stellar Atmosphere Program. II: Wavelength Parallelization

We describe an important addition to the parallel implementation of our generalized NLTE stellar atmosphere and radiative transfer computer program PHOENIX. In a previous paper in this series we described data and task parallel algorithms we have developed for radiative transfer, spectral line opacity, and NLTE opacity and rate calculations. These algorithms divided the work spatially or by spectral lines, that is distributing the radial zones, individual spectral lines, or characteristic rays among different processors and employ, in addition task parallelism for logically independent functions (such as atomic and molecular line opacities). For finite, monotonic velocity fields, the radiative transfer equation is an initial value problem in wavelength, and hence each wavelength point depends upon the previous one. However, for sophisticated NLTE models of both static and moving atmospheres needed to accurately describe, e.g., novae and supernovae, the number of wavelength points is very large (200,000--300,000) and hence parallelization over wavelength can lead both to considerable speedup in calculation time and the ability to make use of the aggregate memory available on massively parallel supercomputers. Here, we describe an implementation of a pipelined design for the wavelength parallelization of PHOENIX, where the necessary data from the processor working on a previous wavelength point is sent to the processor working on the succeeding wavelength point as soon as it is known. Our implementation uses a MIMD design based on a relatively small number of standard MPI library calls and is fully portable between serial and parallel computers.Comment: AAS-TeX, 15 pages, full text with figures available at ftp://calvin.physast.uga.edu/pub/preprints/Wavelength-Parallel.ps.gz ApJ, in pres

A review of acute bacterial meningitis in childhood

This paper reviews the epidemiology, pathogenesis and management of acute bacterial meningitis in childhood. The epidemiology of this infection has undergone significant changes with the implementation of effective immunisation, antibiotic therapy and chemoprophylaxis. The reported incidence of bacterial meningitis in children in the Maltese Islands is low compared to other countries. A high index of suspicion is required to diagnose the onset of bacterial meningitis especially in infants. Third-generation cephalosporins are currently the antibiotics of choice for the acute disease. The timely administration of penicillin may be life saving in cases of meningococcal septicaemia. Adjuvant therapy such as dexamethasone may reduce the occurrence and the severity of sequelae, in particular sensorineural hearing loss. Chemoprophylaxis with rifampicin has played an important role in curtailing epidemics of meningococcal disease. The Haemophilus influenzae type b (Hib) vaccine has made a significant impact on the incidence of H. influenzae meningitis in children. Effective vaccines against pneumococci and meningococci (type b) do not yet exist, however ongoing research seeks to produce these vaccines in an effort to emulate the successful outcome attained by the Hib vaccine.peer-reviewe

Officer-Involved Domestic Violence: The Mediating Factors

Domestic and family violence has been a critical issue in contemporary society. Efforts have been made in researching the causes, effects, and mediating factors of domestic violence in relation to the workplace. Studies demonstrate that a relationship between conflict crossing over from the work to the home environment exist. Additional studies demonstrate that domestic violence does affect the workplace; however, there is little to no scientific data on the reverse relationship. The reverse relationship regards whether the workplace affects the occurrence of domestic violence. This research paper will dive into this topic, and on the lack of data available. Supporting data will illustrate that factors from the workplace do affect the likelihood of domestic and/or family violence occurring in police families. Not considering or viewing police family violence as an effect of workplace factors is shortsighted, and it demonstrates the need for education on this topic. With new data, comes new policies and implications that are reconfigurations of the existing policies. There is a need to bring this subject to light, and in view of the law enforcement community

Counterfactuals of Ontological Dependence

A great deal has been written about 'would' counterfactuals of causal dependence. Comparatively little has been said regarding 'would' counterfactuals of ontological dependence. The standard Lewis-Stalnaker semantics is inadequate for handling such counterfactuals. That's because some of these counterfactuals are counterpossibles, and the standard Lewis-Stalnaker semantics trivializes for counterpossibles. Fortunately, there is a straightforward extension of the Lewis-Stalnaker semantics available that handles counterpossibles: simply take Lewis's closeness relation that orders possible worlds and unleash it across impossible worlds. To apply the extended semantics, an account of the closeness relation for counterpossibles is needed. In this paper I offer a strategy for evaluating 'would' counterfactuals of ontological dependence that understands closeness between worlds in terms of the metaphysical concept of grounding

Women and Girls Equality: A Clear Focus For Social Investing

Gender lens investing is the strategy of putting investment capital to work with the goal of improving the lives of women and girls. Social investment products with this gender focus can be found in multiple asset classes and at varying levels of risk and return. Historically, they have included community development notes, microfinance, private equity, venture capital, pooled funds and managed accounts. Such investments sometimes have a direct, grassroots impact -- for example, financing a catering business owned by women that serves nutritious meals to children in public schools, or providing poor women in India access to low-interest loans to foster the development of cottage industries. Another related strategy for creating social change has been to invest in companies that have progressive corporate employment policies that seek to promote gender equality in the workplace.Whatever the investment vehicle or approach, the mission is the same. Endowments, foundations and individual investors recognize that focusing their investments in this way can not only create benefits and opportunities for individual women and girls but also help provide economic security for their families and communities. Organizations, too, have embraced the idea that investing in gender equality is a powerful strategy for promoting social change. A study by the Foundation Center and the Women's Funding Network found that foundation grants benefiting women and girls are growing at a faster pace than foundation giving as a whole. Women investors in particular often want their investments to support women's issues and to have a positive impact on their gender