Booster HBV vaccination; is it really necessary?

Egypt J Pediatr Allergy Immunol 2011;9(2):9

Diffusion and advection in two-dimensional rotating flow

This paper presents the results of an investigation of mass transport by diffusion and advection in two-dimensional steady, spatially varied confined flow. In practice, this type of flow occurs in recirculating regions ofstreams and rivers or behind hydraulic structures. A simple vorticity transport model is used to simulate shear-induced flow in a square region confined on three sides and open to a uniform flow on one side. The differential equation governing diffusion and advection of a known quantity of tracer mass introduced in such flow is solved. The solution scheme is based on Galerkin finite element approximation of the transport equation. Diffusion is represented by a second-order tensor, the components of which are related to the eddy diffusion coefficient, as well as the magnitude and direction of the mean local velocity. The unsteady transport term is approximated by implicit finite differencing in time. Simulation results are given for one and two-dimensional test cases and for shear induced rotating flow.U.S. Department of the InteriorU.S. Geological SurveyOpe

Modeling streamlines and mass transport in circulating flow

State-of-the-art of hydraulic and water quality modeling in streams and rivers does not include the role of large, slowly circulating regions in dilution and transport of effluents discharged in such water bodies. Examples of circulating regions include meander, blocked arms of the stream, and flow behind engineering structures such as jetties, wing dams, and bridge piers as well as flow within small marinas and fleeting areas. Numerical schemes have been developed to simulate streamline patterns and mass transport within a circulating region approximated by a square cavity on the side of a channel. The circulating flow is assumed two-dimensional (depth averaged) and is generated and maintained by a known main flow at the open boundary. Results are given for characteristic Reynolds numbers ranging from 500 to 30,000. The equation governing the mixing and transport of a finite quantity of conservative tracer instantaneously introduced at any location in the flow field has been numerically solved. The numerical scheme is based on the finite element approximation of the governing differential equation and uses the method of weighted residuals. The flow geometry is represented by triangular elements, and a linear basis function is used in the interpolation scheme. The unsteady term is approximated by finite differencing in full-forward time steps. Dispersion coefficient has been represented as a first-order tensor, the components of which are functions of the dispersion coefficients along and normal to the streamlines. Results are given for scalar and vectorized dispersion coefficients as well as a range of computation time steps.U.S. Department of the InteriorU.S. Geological SurveyOpe

Preliminary report of hepatitis B virus genotype prevalence in Iran

Aim: To determine the prevalence of hepatitis B virus (HBV) genotypes in Iranian hepatitis B surface antigen (HBsAg) carriers, chronic hepatitis B and cirrhotic patients. Methods: A total of 109 HBsAg-positive patients were included in this study. HBV genotypes were determined by using INNO-LiPA methodology which is based on the reverse hybridization principle. Results: The distribution of patients with different stages of liver disease was as follows: 95 (86.4) chronic hepatitis, 11 (10) liver cirrhosis, and 3 (2.7) inactive carrier. Of the chronic hepatitis and liver cirrhosis patients, 26.4 were HBeAg-positive while 70 were HBeAg-negative. Genotype D was the only detected type found in all patients. Conclusion: Classifying HBV into genotypes has to be cost-effective and clinically relevant. Our study indicates that HBV genotype D prevails in the Mediterranean area, Near and Middle East, and South Asia. Continued efforts for understanding HBV genotype through international co-operation will reveal further virological diffierences of the genotypes and their clinical relevance. © 2006 The WJG Press. All rights reserved

Multi-job production systems: definition, problems, and product-mix performance portrait of serial lines

This paper pursues two goals: (a) Define a class of widely used in practice flexible manufacturing systems, referred to as Multi-Job Production (MJP) and formulate industrially motivated problems related to their performance. (b) Provide initial results concerning some of these problems pertaining to analysis of the throughput and bottlenecks of MJP serial lines as functions of the product-mix. In MJP systems, all job-types are processed by the same sequence of manufacturing operations, but with different processing time at some or all machines. To analyse MJP with unreliable machines, we introduce the work-based model of production systems, which is insensitive to whether single- or multi-job manufacturing takes place. Based on this model, we investigate the performance of MJP lines as a function of the product-mix. We show, in particular, that for the so-called conflicting jobs there exists a range of product-mixes, wherein the throughput of MJP is larger than that of any constituent job-type manufactured in a single-job regime. To characterise the global behaviour of MJP lines, we introduce the Product-Mix Performance Portrait, which represents the system properties for all product-mixes and which can be used for operations management. Finally, we report the results of an application at an automotive assembly plant

Prevalence and determinants of diabetes mellitus among Iranian patients with chronic liver disease

BACKGROUND: Alterations in carbohydrate metabolism are frequently observed in cirrhosis. We conducted this study to define the prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in Iranian patients with chronic liver disease (CLD), and explore the factors associated with DM in these patients. METHODS: One hundred and eighty-five patients with CLD were enrolled into the study. Fasting plasma glucose and two-hour plasma glucose were measured in patients' sera. DM and IGT were diagnosed according to the latest American Diabetes Association criteria. RESULTS: The subjects included 42 inactive HBV carriers with a mean age of 42.2 ± 12.0 years, 102 patients with HBV or HCV chronic hepatitis with a mean age of 41.2 ± 10.9 years, and 41 cirrhotic patients with a mean age of 52.1 ± 11.4 years. DM and IGT were diagnosed in 40 (21.6%) and 21 (11.4%) patients, respectively. Univariate analysis showed that age (P = 0.000), CLD status (P = 0.000), history of hypertension (P = 0.007), family history of DM (P = 0.000), and body mass index (BMI) (P = 0.009) were associated with DM. Using Multivariate analysis, age (OR = 4.7, 95%CI: 1.8–12.2), family history of DM (OR = 6.6, 95%CI: 2.6–17.6), chronic hepatitis (OR = 11.6, 95%CI: 2.9–45.4), and cirrhosis (OR = 6.5, 95%CI: 2.4–17.4) remained as the factors independently associated with DM. When patients with cirrhosis and chronic hepatitis were analyzed separately, higher Child-Pugh's score in cirrhotic patients (OR = 9.6, 95%CI: 1.0–88.4) and older age (OR = 7.2, 95%CI: 1.0–49.1), higher fibrosis score (OR = 59.5, 95%CI: 2.9–1211.3/ OR = 11.9, 95%CI: 1.0–132.2), and higher BMI (OR = 30.3, 95%CI: 3.0–306.7) in patients with chronic hepatitis were found to be associated with higher prevalence of DM. CONCLUSIONS: Our findings indicate that patients with cirrhosis and chronic hepatitis are at the increased risk of DM occurrence. Older age, severe liver disease, and obesity were associated with DM in these patients

Study on age-related bioaccumulation of some heavy metals in the soft tissue of rock oyster (Saccostrea cucullata) from Laft Port – Qeshm Island, Iran

Heavy metals widely enter into aquatic ecosystems, and cause various environmental problems due to bioaccumulation and biomagnification in food chains. The accumulation of heavy metals in bivalve tissues is affected by a number of intrinsic and extrinsic factors such as physiological conditions, growth, seasonal changes, pH, salinity, temperature, genera and age. The present study investigated the effects of age of the rock oyster Saccostrea cucullata on the accumulation of Ni, Cd and Pb in the Laft Port coast located on the Qeshm Island. 200 oysters were collected and their age was determined, then they were classified into four age categories and 15 oysters from each category were selected. Samples were dry digested and the metal concentrations were measured by an ICP-OES (PerkinElmer, USA) instrument. Results revealed that the accumulation of Ni and Pb in one year old oysters (immature) was more than those in mature oysters (two, three and four year old oysters). Significant differences were observed between concentrations of Ni and Pb in mature and immature oysters. The results suggested that aging has a negative effect on bioaccumulation of Ni and Pb in S. cucullata; while it has no effect on bioaccumulation of Cd

Epidemiological and Clinical Characteristics of Scorpion Stings in Ahwaz, Southwest Iran (2006-2010)

Background: Scorpion sting is a health problem in the world including tropical regions of Iran as in rural region of Khuzestan province. Therefore appropriate diagnosis and treatment has a special aspect. The aim of present study was to evaluation of demographic status and clinical aspect of scorpion sting patient due to better prevention and treatment and diagnosis.Methods: This survey done by analyzing medical records of patients suffered from scorpion sting, hospitalize in Razi hospital in Khuzestan province (southwest of Iran) among 2006-2010. Patient information have been extracted and inserted in the inquiry form and data were analyzed by SPSS software.Results: In the present study 1922 patients have been studied. Proportion of females stung by scorpion to male was 1.29 to 1. Place of sting were mostly trunk (693 cases =36.05%) and remains were on other part of body. About 419 persons (21.8 %) have come to hospital about 6-24 hours after being stung and 708 people (36.83 %) came there in less than 6 hours. Most sting (41.2 %) were at night time and other were at daylight. 1308 persons were stung by an unknown black and yellow scorpion and 614 cases (31.94%) by scorpion known as Hemiscorpius lepturus. 708 persons of patients (39.83%) have been suffered from hemoglobinoria , 709 persons (39.88%) were suffered from coagulation dysfunction. Totally 508 persons of patients (26.43%) received blood products. 36 of patients were died, of which 24 cases (1.24%) were female and 12 patients (0.62%) were male. most of patients (1842 cases  95.83%) were hospitalized 1-2 days.Conclusion: In this survey, Patients at the emergency units showed signs of local and systemic effects, 36 patients were died. We propose that public awareness and physician readiness combined with the availability of effective antivenom has potential value in reducing complications and lethality in scorpion envenomation