3,206 research outputs found
Factors related to attrition in a cohort study of HIV in Malawi
Background: Longitudinal studies face power reduction due to loss to follow up (LTFU). Bias may also arise because of differences between those who stay in the study and those who are LTFU We studied factors associated with LTFU in a cohort of HIV sero-negative and sera-positive mothers in urban Malawi.Objective: To bridge the existing gaps by examining the factors associated with attrition.Design: Longitudinal study.Setting: Queen Elizabeth Central Hospital (QECH) and the Kamuzu Central Hospital in Blantyre, Malawi.Subjects: One thousand three hundred and fifty three women who attended the prenatal clinic, between October 1989 and October 1990 were recruited as part of a study to determine rates and risk factors of sero-prevalence and sera-conversion of HIV -1 among this cohort.Results: In this cohort study, 1353 women were enrolled at delivery and 1188 (88%) returned for the first follow-up visit at three months post-partum. Of those who returned, 177 (15%) were subsequently lost during the remaining months of follow-up. The main predictors of L TFU were younger maternal age, lower educational level of the father, HIV infection of the mother, lower birth weight of the index child and mother not being married.Conclusions: Researchers planning studies in developing countries should consider the impact of lower education and poorer infant health on study retention in developing countries
Psychiatric morbidity in two urban communities in Nigeria
Background: There is a welter of evidence for an inverse relationship between socio-economic status (SES) and mental health. The relationship is grossly under researched in the developing countries.
Objective: To ascertain rates of gross psychiatric morbidity and some demographic correlations in two communities with different socio-economic standards.
Design: A cross-sectional community based study.
Subjects: Random samples of two socio-economically dissimilar communities (N1 = 189, N2 = 148) were assessed for psychiatric morbidity.
Results: Rates of psychiatric morbidity obtained for the lower status community (Ajegunle) and the higher status community (Victoria Island/Ikoyi) on the GH Q-12 were 26.5 and 14.2 respectively and the corresponding figures on the SRQ (non-psychosis) were 41.8 and 18.2 and on the SRQ (psychosis) 61.5 and 31.7. A large number of positive socio-demographic correlations between cases and non-cases were obtained on SRQ and GHQ-12 in both communities. Family history of psychiatric illness significantly differentiates cases from non-cases on all measures of morbidity.
Conclusion: The socio-economic inequality demonstrated should be minimised by evolving a social welfare policy in Nigeria and other developing countries that is responsive to the survival needs of the populace and ensures equitable distribution of resources across socio-economic strata. There is dire need for further research into the complex bearings of the link between social status and psychological wellness in the developing world.East African Medical Journal Vol. 85 (8) 2008: pp. 368-37
Physiological Response Of Laying Birds To Neem (Azadirachta Indica) Leaf Meal-Based Diets: Body Weight Organ Characteristics And Haematology
A 12-weeks feeding trial was conducted to evaluate the effects of Neem (Azadirachta indica) leafmeal (NLM) on body weight gain, carcass and organ characteristics and haematological values of laying hens. The leaves were harvested, chopped to facilitate drying in the sun until they became crispy but still greenish in coloration. The Sun-dried leaves were milled using a hammer mill to produce the leaf meal. Four layers diets were formulated to contain the NLM at 0%,5%, 10% and 15% dietary levels respectively and were used to feed 120 Shikka brown layers already 10 months in lay. The birds were divided into 4 groups of 30 each and randomly assigned to the 4 treatment diets in a completely randomized design (CRD). NLM did not show any appreciable difference in weight gain between the birds at 0% and those at 5%, 10% dietary levels. Carcass weight, dressed weight, liver, heart and gizzard weights were significantly (P<0.05) increased at 5% dietary level of NLM. There were no significant difference in Hb and PCV between birds on O% and 5% treatment diets. However, these differed significantly (P<0.05%) from those of birds on 10% and 15% treatment diets. There were variations in the differential WB count , marked lymphocytopenia adversely affected the total leucocyte counts in the birds on 5%, 10% and 15% treatment diets. The results of this study suggest that laying birds could tolerate 5%- 15% dietary levels of NLM without deleterious effects
Comparative Assessment of the Fracture Behaviour of API‐5L X65 and Micro‐alloyed Steels in E80 Simulated Fuel Ethanol Environment
Monotonic J‐integral tests were carried out on API‐5L X65 steel and micro‐alloyed steel (MAS) in E80
simulated fuel grade ethanol (SFGE) environment using three‐point bend specimens. A ramp rate of
10-04 mm/s was used for loading in each sequence so as to enhance stress corrosion cracking (SCC)
influence if any. The influence of the SFGE environment on tearing resistance and fracture toughness of
the steels was studied. Both steels exhibited decrease in fracture toughness in E80 in relation to air. The
decrease in fracture toughness may be due to anodic dissolution at the crack tip. Ductile tearing
resistance of the steels increased in E80 due to decline in toughness property. In comparison with X65
steel, MAS showed better fracture properties
Evaluation of the concentration of toxic metals in cosmetic products in Nigeria
It has been shown that heavy metals toxicity to humans is as a result of long term or high level exposure to pollutants common in the environment including the air, water, food and numerous consumer products such as the cosmetics and toiletries. In this study, we assessed the levels of toxic metals in different cosmetic products sold at local shops in Lagos, Nigeria. The cosmetic items included thirty creams and twenty lipsticks and lip glosses. These items were purchased from various shops at different locations in Lagos. The cosmetics were analyzed for heavy metals (arsenic, cadmium, lead, mercury and nickel) after digestion with concentrated acids HNO3: H2SO4: HClO4 in ratio 2:2:1. The concentrations of the selected toxic heavy metals were determined in duplicate using a Buck 205 flame atomic absorption spectrophotometer. All the samples analyzed contained a detectable amount of all the metals of interest. The concentration of the heavy metals in the samples ranged from 0.006 to 0.207 ppm. It is obvious from the present study that the use of some cosmetic products exposes users to low concentrations of toxic heavy metals which could constitute potential health risk to users since it has been known that heavy metals can accumulate in the biological system over time and are known to induce skin problems or diseases such as cancer. Further research to better understand the sources of heavy metals in cosmetic products is recommended.Key words: Toxic heavy metals, cosmetics, atomic absorption spectrophotometer, environment
Effect of differential uniform temperature with thickness-wise linear temperature gradient oninterfacial stresses of a bi-material assembly
The thermal mismatch induced interfacial stresses are one of the major reliability issues in electronic packaging and composite materials. Consequently an understanding of the nature of the interfacial stresses under different temperature conditions is essential in order to eliminate or reduce the risk of structural and functional failure. Approach: In this analysis, a model was proposed for the shearing and peeling stresses occurring at the interface of two bonded dissimilar materials with the effect of different uniform temperatures in the layers. The model was then upgraded by accounting thickness wise linear temperature gradients in the layers using two temperature drop ratios. The upgraded models were then compared with the existing uniform temperature model. The proposed model can be seen as a more generalized form to predict interfacial stresses at different temperature conditions that may occur in the layers. Results: The results were presented for an electronic bi-material package consisting of die and die-attach. Conclusion: The numerical simulation is in a good matching agreement with analytical results
(E)-3-[2-(4-Chlorophenylsulfonyl)vinyl]-6-methyl-4H-chromen-4-one
In the title compound, C18H13ClO4S, the mean planes of the chlorophenyl ring and the S—C=C—C chain are oriented at angles of 52.7 (2) and 51.3 (2)°, respectively, with respect to the sulfonyl (O=S=O) plane. The dihedral angle between the mean planes of the chlorophenyl group and the benzopyran ring is 80.7 (1)°. The crystal structure is stabilized by two intermolecular C—H⋯O interactions, forming centrosymmetrc dimers, which are linked via a second C—H⋯O interaction into a chain structure
Intermediate and high peri-operative cardiac enzyme release following isolated coronary artery bypass surgery are independently associated with higher one-year mortality
BACKGROUND: The relationship between cardiac enzyme (CE) release following coronary artery bypass surgery (CABG) and medium term outcome is unclear. We sought to determine the relationship between post-operative CE release and one-year survival following isolated CABG. METHODS: Over three years 3,024 consecutive patients underwent isolated CABG. Patient characteristics were prospectively recorded in a cardiac surgical database. CE release, taken as the highest single measurement recorded in the first 24 hours post-op, was abstracted from an electronic archive. All cause mortality was taken from a national registry of deaths. RESULTS: Data were complete for 2,860 (94.6%) patients. CK-MB isoenzyme (reference range 5–24 U/l) was recorded in 2,568 (89.8%), total CK in 292 (10.2%). CE release three or more times the upper limit of the reference range (ULR) were recorded in 498 (17.4%) patients, 163 (5.7%) patients had CE more than six times ULR. There were 122 deaths (4.3%). Cox proportional hazards analysis showed that CE release 3–6 times ULR (adjusted HR 2.1 [95% CI: 1.6 to 2.6], p = 0.002) and CE release six or more times the ULR (adjusted HR 5.0 [95% CI: 4.5 to 5.4], p < 0.001) were independently associated with increased one-year mortality. CONCLUSION: Cardiac enzyme release following CABG is associated with increased one-year all-cause mortality. The definition of peri-operative myocardial infarction following CABG should include elevation of CK-MB three or more times the upper limit of normal
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