A multilocus likelihood approach to joint modeling of linkage, parental diplotype and gene order in a full-sib family

BACKGROUND: Unlike a pedigree initiated with two inbred lines, a full-sib family derived from two outbred parents frequently has many different segregation types of markers whose linkage phases are not known prior to linkage analysis. RESULTS: We formulate a general model of simultaneously estimating linkage, parental diplotype and gene order through multi-point analysis in a full-sib family. Our model is based on a multinomial mixture model taking into account different diplotypes and gene orders, weighted by their corresponding occurring probabilities. The EM algorithm is implemented to provide the maximum likelihood estimates of the linkage, parental diplotype and gene order over any type of markers. CONCLUSIONS: Through simulation studies, this model is found to be more computationally efficient compared with existing models for linkage mapping. We discuss the extension of the model and its implications for genome mapping in outcrossing species

Renormalization formalism for superconducting phase transition with inner-Cooper-pair dynamics

As charge carrier of the macroscopic superconductivity, the Cooper pair is a composite particle of two paired electrons, which has both center-of-mass and inner-pair degrees of freedom. In most cases, these two different degrees of freedom can be well described by the macroscopic Ginzburg-Landau theory and the microscopic Bardeen-Cooper-Schrieffer (BCS) theory, respectively. Near the superconducting phase transition where the Cooper pair is fragile and unstable because of the small binding energy, there are non-trivial couplings between these two different degrees of freedom due to such as finite energy and/or momentum transfer. The non-trivial couplings make the original derivation of the Ginzburg-Landau theory from the BCS theory fail in principle as where these two different degrees of freedom should not be decoupled. In this manuscript, we will present a renormalization formalism for an extended Ginzburg-Landau action for the superconducting phase transition where there is finite energy transfer between the center-of-mass and the inner-pair degrees of freedom of Cooper pairs. This formalism will provide a theoretical tool to study the unusual effects of the inner-pair time-retarded physics on the superconducting phase transition.Comment: 10 pages, 4 figure

Occupational skin diseases and prevention among sanitation workers in China

Background: Little research has been focused on the health status or the occupational protection awareness of sanitation workers. The policy recommendations on the occupational safety and health of sanitation workers based on the scientific research are also insufficient in developing countries like China. Objective: To study the incidence of dermatoses and the relevance with occupational exposure, protection awareness and protective measures among sanitation workers for better management and protection of the sanitation workers. Methods: 273 sanitation workers and 113 administrative staff from 11 streets of Wuhan were recruited. Dermatological problems were evaluated and recorded by physical examination. Occupational exposure, protection awareness, the use of protective equipments and personal history of skin disease were assessed by questionnaires. Results: Compared with administrative staff, sanitation workers had much more occupational dermatological problems and had a much higher rate of harmful ultraviolet ray exposure. Young sanitation workers were more aware of occupational self-protection and a relatively higher rate of them using protective equipments compared with old ones. Conclusion: Exposure to multiple health hazards and the poor use of protective equipments are related to skin diseases in sanitation workers. Prejob training of self-protection and the use of protective equipments are recommended