The prediction of wake wash in the towing tank

The wash or ship-generated waves from high speed craft has become a common subject in research and development of marine transportation. Since some time now the wake wash of high speed craft has become a problem in particular on inland or confined waterways. This wake wash has an impact on safety and environment such as bank/shoreline erosion, risk to people on shore and small boats in harbors and changes in the local ecology. This paper describes the results of model test of a high speed patrol, together with theoretical prediction of wake wash

Investigating ethnic inequalities in the incidence of sexually transmitted infections: mathematical modelling study.

OBJECTIVES: To investigate ethnic differences in rates of gonorrhoea using empirical sexual behaviour data in a simple mathematical model. To explore the impact of different intervention strategies in this simulated population. METHODS: The findings from cross sectional studies of gonorrhoea rates and sexual behaviour in three ethnic groups in south east London were used to determine the parameters for a deterministic, mathematical model of gonorrhoea transmission dynamics, in a population stratified by sex, sexual activity (rate of partner change), and ethnic group (white, black African, and black Caribbean). We compared predicted and observed rates of infection and simulated the effects of targeted and population-wide intervention strategies. RESULTS: In model simulations the reported sexual behaviours and mixing patterns generated major differences in the rates of gonorrhoea experienced by each subpopulation. The fit of the model to observed data was sensitive to assumptions about the degree of mixing by level of sexual activity, the numbers of sexual partnerships reported by men and women, and the degree to which observed data underestimate female infection rates. Interventions to reduce duration of infection were most effective when targeted at black Caribbeans. CONCLUSIONS: Average measures of sexual behaviour in large populations are inadequate descriptors for the epidemiology of gonorrhoea. The consistency between the model results and empirical data shows that profound differences in gonorrhoea rates between ethnic groups can be explained by modest differences in a limited number of sexual behaviours and mixing patterns. Targeting effective services to particular ethnic groups can have a disproportionate influence on disease reduction in the whole community

A new distributional record of Zozymodes cavipes (Dana, 1852) (Crustacea; Decapoda) from the coastal waters of Pakistan

One male and one female of Zozymodes cavipes (Dana, 1852) have revently been collected from the rocky shores near Karachi; the species is widely distributed in the Indo-Pacific region. It is, however, being reported for the first time from the pakistani coast of the northern Arabian Sea and thus fills the gap in the known distribution of the species. The pakistani material is housed in the Marine Reference Collection Centre, University of Karachi. The specimens are briefly descibed below. Only restricted synonym is given

Occurrence of four Xanthid (Brachyura) crabs in Karachi waters (northern Arabian Sea)

Four Xanthid crabs, namely Euxanthus exsculptus (Herbst), Halimede ochtodes (Herbst), Medaeops edwardsi Guinot, and Neolimera intermadia Odhner, previously not known from the northern Arabian Sea are being reported. Each species is briefly described and illustrated

An Indian Ocean record for a porcellanid crab, Raphidopus ciliatus Stimpson, 1958

Several specimens of a porcellanid crab Raphidopus ciliatus are being reported for the first time from the northern Arabian Sea, extending the range of the species into the Indian Ocean. Specimens were found in by-catches landing at fish harbour, four specimens were recovered from stomachs of noncommercial fish, Batrachus grunniens. Salient features of the species are described. Individual variations specially noted

Recovery of a leucosid crab Nursia abbreviata Bell, 1855 from Arabian Sea fish

On two occasions Nursia abbreviata Bell, 1855 has been recovered from the stomachs of Batrochus grunniens (Linnaeus, 1758) caught with commercial fish. Nursia abbreviata has been previously recorded from Karachi by Alcock (1896). The present specimens afford the first subsequent record of the species from the region, and are represented by only two males recovered from fish stomachs. The only other species of the genus from Pakistan is N. Rubifera Muller, 1866 which is common in shore collections (Tirmizi and Kazmi, 1988). A brief description of the present material is given below

The exp-log normal form of types

Lambda calculi with algebraic data types lie at the core of functional programming languages and proof assistants, but conceal at least two fundamental theoretical problems already in the presence of the simplest non-trivial data type, the sum type. First, we do not know of an explicit and implemented algorithm for deciding the beta-eta-equality of terms---and this in spite of the first decidability results proven two decades ago. Second, it is not clear how to decide when two types are essentially the same, i.e. isomorphic, in spite of the meta-theoretic results on decidability of the isomorphism. In this paper, we present the exp-log normal form of types---derived from the representation of exponential polynomials via the unary exponential and logarithmic functions---that any type built from arrows, products, and sums, can be isomorphically mapped to. The type normal form can be used as a simple heuristic for deciding type isomorphism, thanks to the fact that it is a systematic application of the high-school identities. We then show that the type normal form allows to reduce the standard beta-eta equational theory of the lambda calculus to a specialized version of itself, while preserving the completeness of equality on terms. We end by describing an alternative representation of normal terms of the lambda calculus with sums, together with a Coq-implemented converter into/from our new term calculus. The difference with the only other previously implemented heuristic for deciding interesting instances of eta-equality by Balat, Di Cosmo, and Fiore, is that we exploit the type information of terms substantially and this often allows us to obtain a canonical representation of terms without performing sophisticated term analyses

Oral Cancer Awareness and its Determinants among a Selected Malaysian Population

Objective: To assess oral cancer awareness, its associated factors and related sources of information among a selected group of Malaysians. Methods: A cross-sectional survey was conducted on all Malaysian ethnic groups aged >= 15 years old at eight strategically chosen shopping malls within a two week time period. Data were analysed using chi-square tests and multiple logistic regression. Significance level was set at alpha<0.05. Results: Most (84.2%) respondents had heard of oral cancer. Smoking was the most (92.4%) recognized high risk habit. Similar levels of awareness were seen for unhealed ulcers (57.3%) and red/white patches (58.0%) as signs of oral cancer. Age, gender, ethnicity, marital status, education, occupation and income were significantly associated with oral cancer awareness (p<0.05). Conclusions: There was a general lack of awareness regarding the risk habits, early signs and symptoms, and the benefits of detecting this disease at an early stage. Mass media and health campaigns were the main sources of information about oral cancer. In our Malaysian population, gender and age were significantly associated with the awareness of early signs and symptoms and prevention of oral cancer, respectively.Article Link: http://koreascience.or.kr/article/ArticleFullRecord.jsp?cn=POCPA9_2013_v14n3_195

Low Incidence of Contrast Induced Nephropathy after Coronary Angiography in Patients with Advanced Chronic Kidney Disease Treated with Prophylactic Continuous Veno-venous Hemofiltration

Introduction: Contrast-induced nephropathy (CIN) is associated with increased risk of in-hospital morbidity and mortality. The purpose of this study was to find out whether continuous venovenous hemofiltration (CVVH) after coronary angiography in chronic kidney disease (CKD) patients is associated with a lower incidence of CIN than that reported in the literature. Methods: All patients with CKD who underwent coronary angiography in the Chest Disease Hospital, Kuwait, between January 2004 and December 2005 were treated by CVVH after the procedure. Renal function was assessed before and after the procedure. Results: A total of 98 patients were enrolled in the study, 52 (53.1%) of whom were males. Their mean age was 60.7 years. Before the procedure, the mean serum creatinine level was 4.65 mg/dl and the mean creatinine clearance (Cr Cl) was 18.04 ml/min. Patients underwent CVVH for a mean duration of 21.3 hours, after a mean time-interval of 44.3 min. Their mean serum creatinine was 4.57 mg/dl at discharge (within the first week after the procedure) and 4.78 mg/dl at 15 days after the procedure. Mean Cr Cl was 18.52 ml/min at discharge and 17.62 ml/min at 15 days after the procedure. There was no statistically significant difference between the mean serum creatinine and Cr Cl values before and after the procedure. However, one patient (1.02%) developed CIN and ended on regular hemodialysis. The in-hospital mortality was 0%. Conclusion: Patients with advanced CKD who undergo coronary angiography may be protected from further deterioration in their renal function after exposure to radiological contrast material if the procedure is immediately followed by CVVH. A randomized controlled clinical trial is needed to verify our encouraging results. Keywords: contrast induced nephropathy, chronic kidney disease, continuous venovenous hemofiltratio