Effect of Bolt Layout on the Mechanical Behavior of Four Bolted Shear Joint using Three – Dimensional Finite Element Analysis

Bolted joint is a typical connection that is widely used in the machine assemblies and construction of structural components etc. Bolted joints when put in use encounter one or more type of working loads. In general, analysis of bolted joint is not simple, it involves many factors such as bolt pretensioning, number of bolts, number of members, clearance between the bolt and hole, flange thickness, loading conditions and friction coefficient, etc. Here, a comprehensive study is conducted to investigate the effect of four-bolted joint layout on the mechanical behavior of the joint. Threedimensional model is analyzed in shear type of loading. This model helps us to visualize the localized points of high stress concentration that is not possible by using two dimensional or axisymmetric models. Displacement pattern and stress distribution in different arrangements is studied. Critical regions and the critical bolt are being identified

Anaemia in pregnancy: occurrence in two economically different clinic populations of Karachi

According to previous WHO standards, anaemia in pregnancy denoted a haemoglobin level of 11.0 gms/dl or less, but this is now considered to be variable1 as it differs from country to country depending on local reference ranges and socio-economic conditions. Each country should “lay down minimal acceptable standards” below which an individual is considered to be anaemic, taking into account the available fmancial and manpower resources and other health needs of the country2. There is a wide divergence in the quoted prevalence of anaemia in Pakistan and neigh­bouring countries.3-6 This study was undertaken to determine a range of haemoglobin levels and frequency of anaemia in pregnancy in 2 clinic populations of Karachi. This study emphasises the relationship between anaemia and socio-economic levels of the population

Neonatal screening for congenital hypothyroidism in Pakistan

Congenital hypothyroidism is a preventable cause of mental retardation. Since clinical signs of congenital hypothyroidism do not generally become obvious before three months of age, screening programmes have been introduced in North America and Europe, which consist of T4 or TSH screening on newborn infants on the third day of life. The screening for congenital hypothyroidism was initiated in Pakistan by the Aga Khan University Hospital (AKUH) in March 1987. By April 1988, 5000 neonates were screened and five cases of congenital hypothyroidism were diagnosed. The study revealed the incidence of hypothyroidism to be one case per 1000 newborns which is about 4 times more than that in the Wes

A High Order Numerical Scheme for Incompress ible Navier-Stokes Equations

To solve the incompressible Navier-Stokes equations in a generalized coordinate system, a high order solver is presented. An exact projection method/fractional-step scheme is used in this study. Convective terms of the Navier-Stokes (N-S) equations are solved using fifth-order WENO spatial operators, and for the diffusion terms, a sixth-order compact central difference scheme is employed. The third-order Runge-Kutta (R-K) explicit time-integrating scheme with total variation diminishing (TVD) is adopted for the unsteady flow computations. The advantage of using a WENO scheme is that it can resolve applications using less number of grid points. Benchmark cases such as, driven cavity flow, Taylor-Green (TG) vortex, double shear layer, backward-facing step, and skewed cavity are used to investigate the accuracy of the scheme for two dimensional flow

Cardiovascular risk factors in school children from low middle income families in Karachi, Pakistan

Serum levels of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) and trigly cerides (TG) were determined on 239 school children aged 5-19 years belonging to lower middle class families. The mean TC, LDL-C, HDL-C and TG ranged from 3.70-4.37 mmol/L, 2.17- 2.70 mmol/L, 0.94-1.14 mmol/L, 1.07-1.26 mmol/L respectively. In general, girls had higher TC, LDL-C and HDL-C levels. There was no significant difference in the TG levels between boys and girls. Thirty-three percent of the girls and 22% of the boys had TC level _4.4 mmol/L, the level at which dietary intervention is recommended for children. Fifty-three percent of the girls and 37% of the boys bad TG levels _ than the 90th percentile of the levels for children of similar age and sex in North America. The HDL-C levels were low with 37% of the girls and 44% of boys having values _ the lath percentile of levels for North American children. The mean daily intake of cholesterol ranged from 241 mg to 364 mg/day. Except for the 5-9 year olds, boys had a higher cholesterol intake than girls (P\u3c0.005). Twenty-two percent of the boys and 32% of the girls were overweight but weight status was significantly associated with elevated TC levels only in the boys (P \u3c0.05). Activity level was not significantly related to TC levels but girls who were active had significantly higher HDL-C levels than girls who were sedentary (P \u3c0.02). Family history of cardiovascular disease was significantly associated with elevated cholesterol levels in girls (P \u3c0.05). The results show that the prevalence of cardiovascular risk factors in these school children is relatively high even though they belong to lower middle class families in a developing countr

Platelets and leucocyte counts in pregnancy

A study involving the obstetric clinic population of 3 major teaching hospitals of Karachi has been conducted to define changes in leucocyte and platelet counts as pregnancy progresses. 573 “normal” pregnant women - 183 in the first trimester, 195 in the second trimester and 194 in the third trimester were included in this analysis. We have found leucocytosis to be a feature of normal pregnancy; the change is subsequent to a progressive increase in granulocytes. Platelet counts were found to decrease slightly as pregnancy progresse

Hospital pharmacy practice in Saudi Arabia: Prescribing and transcribing in the Riyadh region

AbstractPurposeThe purpose of this survey is to outline pharmacy services in hospitals on a regional level in the Kingdom of Saudi Arabia.MethodsA modified-American Society of Health-System Pharmacists (ASHP) survey questionnaire as pertinent to Saudi Arabia was used to conduct a national survey. After discussing with the pharmacy directors of 48 hospitals in the Riyadh region over the phone on the survey’s purpose, the questionnaires were personally delivered and collected upon completion. The hospital lists were drawn from the Ministry of Health hospital database.ResultsTwenty-nine hospitals participated in the survey giving a response rate of 60.4%. Approximately 60% of the hospitals which participated in the survey required prior approval for the use of non-formulary medications. About 83.3% of hospitals reviewed compliance with clinical practice guidelines and 72.7% hospitals reported that pharmacists are also actively involved in these activities. Pharmacists in more than 95% of hospitals provided consultations on drug information. A staff pharmacist routinely answering questions was the most frequently cited (74.1%) method by which objective drug information was provided to prescribers. Electronic drug information resources were available in 77.7% of hospitals, although internet use is not widely available to hospital pharmacists, with only 58.6% of hospitals providing pharmacist access to the internet. About, 34.5% of hospitals had computerized prescriber order entry (CPOE) systems with clinical decision-support systems (CDSSs) and 51.9% of the hospitals had electronic medical record (EMR) system.ConclusionHospital pharmacists are increasingly using electronic technologies to improve prescribing and transcribing of medications in Saudi Arabia

Testing an Intentional Naming Scheme Using Genetic Algorithms

Abstract. Various attempts have been made to use genetic algorithms (GAs) for software testing, a problem that consumes a large amount of time and eort in software development. We demonstrate the use of GAs in automating testing of complex data structures and methods for manipulating them, which to our knowledge has not been successfully displayed before on non-trivial software structures. We evaluate the ef-fectiveness of our GA-based test suite generation technique by applying it to test the design and implementation of the Intentional Naming Sys-tem (INS), a new scheme for resource discovery and service location in a dynamic networked environment. Our analysis using GAs reveals serious problems with both the design of INS and its inventors ' implementation.

Effect of exogenous application of nicotinic acid on morpho-physiological characteristics of Hordeum vulgare L. under water stress

Abiotic stresses, such as high temperature and drought conditions, greatly influence the development of plants and the quality and quantity of products. Barley (Hordeum vulgare L.) crop production is largely impacted by drought, affecting growth, yield, and ultimately the productivity of the crop in hot arid/semi-arid conditions. The current pot experiment was directed to observe the outcome of nicotinic acid (NA) treatments on barley’s physiological, biochemical, and production attributes at two capacity levels, i.e., 100% normal range and withholding water stress. Randomized complete block design (RCBD) was used during the experimentation with the two-factor factorial arrangement. NA was applied exogenously by two different methods, i.e., foliar and soil application (fertigation). NA solution contained various application levels, such as T1 = control, foliar applications (T2 = 0.7368 gL−1, T3 = 1.477 gL−1, T4 = 2.2159 gL−1), and soil applications (T5 = 0.4924 gL−1, T6 = 0.9848 gL−1, and T7 = 1.4773 gL−1). Results depicted that, overall, foliar treatments showed better effects than control and soil treatments. Plant growth was preeminent under T4 treatment, such as plant height (71.07 cm), relative water content (84.0%), leaf water potential (39.73-MPa), leaf area index (36.53 cm2), biological yield (15.10 kgha−1), grain yield (14.40 kgha−1), harvest index (57.70%), catalase (1.54 mmolg−1FW−1), peroxidase (1.90 g−1FWmin−1), and superoxide dismutase (52.60 µgFW−1) were superior under T4 treatment. Soil plant analysis development (54.13 µgcm−2) value was also higher under T4 treatment and lowest under T7 treatment. In conclusion, NA-treated plants were more successful in maintaining growth attributes than non-treated plants; therefore, the NA foliar treatment at the rate of 2.2159 gL−1 is suggested to find economical crop yield under drought conditions. The present study would contribute significantly to improving the drought tolerance potential of barley through exogenous NA supply in water deficit areas