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Relationship between adiposity and admixture in African-American and Hispanic-American women.
ObjectiveThe objective of this study was to investigate whether differences in admixture in African-American (AFA) and Hispanic-American (HA) adult women are associated with adiposity and adipose distribution.DesignThe proportion of European, sub-Saharan African and Amerindian admixture was estimated for AFA and HA women in the Women's Heath Initiative using 92 ancestry informative markers. Analyses assessed the relationship between admixture and adiposity indices.SubjectsThe subjects included 11 712 AFA and 5088 HA self-identified post-menopausal women.ResultsThere was a significant positive association between body mass index (BMI) and African admixture when BMI was considered as a continuous variable, and age, education, physical activity, parity, family income and smoking were included covariates (P<10(-4)). A dichotomous model (upper and lower BMI quartiles) showed that African admixture was associated with a high odds ratio (OR=3.27 (for 100% admixture compared with 0% admixture), 95% confidence interval 2.08-5.15). For HA, there was no association between BMI and admixture. In contrast, when waist-to-hip ratio (WHR) was used as a measure of adipose distribution, there was no significant association between WHR and admixture in AFA but there was a strong association in HA (P<10(-4); OR Amerindian admixture=5.93, confidence interval=3.52-9.97).ConclusionThese studies show that: (1) African admixture is associated with BMI in AFA women; (2) Amerindian admixture is associated with WHR but not BMI in HA women; and (3) it may be important to consider different measurements of adiposity and adipose distribution in different ethnic population groups
Crew Motion and the Dynamic Environment of Spaceborne Experiments
Analytical study of crew motion on dynamic environment of orbiting laboratorie
Hydrogeology and Water Quality of Umm Alradhma Aquifer, Eastern Saudi Arabia
Umm Alradhma limestone aquifer represents the most important aquifers in Saudi Arabia. This aquifer is the largest groundwater reservoir in the Arabian Peninsula. It has high potential of groundwater with average saturated thickness of Umm Alradhma 270 m. the average transmissivity, hydraulic conductivity and effective porosity of Umm Alradhma limestone aquifer are 5800 m2/day, 33 m3/day and 30% respectively. The groundwater of the Umm Alradhma limestone aquifer exists under confined condition in the study area. The productivity of the wells reached 704000 m3/day and provided Riyadh City about 300,000 m3/day. The hydrochemical analyses of 52 groundwater samples representing Umm Alradhma limestone aquifer reveal that the groundwater origin is meteoric. The presence of marine salts in groundwater is attributed to the effective leaching and dissolution processes through the flow path within the aquifer materials (limestone, dolomitic limestone and dolomite). The groundwater salinity of the Umm Alradhma limestone aquifer in the study area ranges between 1195-1429 ppm. This suggests that groundwater of Umm Alradhma limestone aquifer is acceptable for domestic, industrial and agricultural purposes. Keywords: Umm Alradhma aquifer, Hydrogeology, Water Qualit
Environmental Impact of Landfill on Groundwater, South East of Riyadh, Saudi Arabia
The main objective of this work had been given to the environmental impact of landfill on groundwater. The groundwater in the study area had problems caused by the landfill and the high volumes of sewage water percolating into the groundwater. The existing soil stratigraphy at the landfill consisting of sandy sheet and fractured limestone lead to increasing leachate percolation into the groundwater. The groundwater resources are used mainly for crop irrigation in an agriculture dominated area. The chemical analysis of groundwater indicates that nitrate pollution can be a serious problem affecting groundwater due to the infiltration of leachate in landfill downward to groundwater and the use of nitrogen (N) fertilizers in agriculture. The high concentrations of NO3- and Zn especially in landfill site in groundwater, likely indicate that groundwater is being significantly affected by leachate percolation. The nitrate and Zinc concentrations in groundwater samples in landfill site reach 191 ppm and 1473 ? g/L respectively. The groundwater in the study area is exploited from fractured limestone aquifer belonging to several limestone formations and groundwater of the concerned aquifer exists under unconfined conditions. The groundwater flow direction is from the northwest to the southeast direction. The leachate produced by waste disposal sites contains large amounts of substances which are likely to contaminate groundwater. Chemical analyses were carried out on groundwater samples collected from the neighborhood of landfill yard and spread to southeast direction. The effects of dumping activity on groundwater appeared most clearly as high concentrations of total dissolved solids (TDS), electrical conductivity (EC), total hardness (TH), chloride, nitrates and sulphates. Groundwater samples from the wells situated close to the landfill were found to be more contaminated than that of the wells situated farther away. Keywords: Environmental Impact, Landfill, Groundwater, Saudi Arabi
Identifying Patterns of Breast Cancer Genetic Signatures using Unsupervised Machine Learning
Deploying machine learning to improve medical diagnosis is a promising area. The purpose of this study is to identify and analyze unique genetic signatures for breast cancer grades using publicly available gene expression microarray data. The classification of cancer types is based on unsupervised feature learning. Unsupervised clustering use matrix algebra based on similarity measures which made it suitable for analyzing gene expression. The main advantage of the proposed approach is the ability to use gene expression data from different grades of breast cancer to generate features that automatically identify and enhance the cancer diagnosis. In this paper, we tested different similarity measures in order to find the best way that identifies the sets of genes with a common function using expression microarray data
The relation between ST-segment resolution and in-hospital mortality after primary percutaneous coronary interventions
Objective: The resolution of ST-segment elevation (>50%) indicates successful reperfusion with thrombolytic therapy. The aim of this study is to evaluate the relation of ST-segment resolution post-primary percutaneous cardiac intervention (PCI) with in-hospital mortality and coronary thrombolysis in myocardial infarction (TIMI) blood flow. Methods: This study is a single-centred retrospective study. The study enrolled 100 patients who were referred to the Nasiriya Heart Centre for primary PCI. We measured the ST segment amplitude in the lead with the highest elevation prior to primary PCI and assessed the ST-segment elevation post-primary PCI. The ratio of ST-segment resolution was calculated and considered complete if reaches ≥70% from the initial ST-segment elevation. We assessed the association of ST-segment resolution with in-hospital mortality. Results: Analysis of the electrocardiogram (ECG) showed that 21 patients (21%) had complete ST-segment (≥ 70%) resolution. No significant association was shown between ST-segment resolution and in-hospital mortality. Two out of 21 patients with complete ST-segment resolution died in the hospital and 6 out of 79 patients with incomplete ST-segment resolution died (P=0.77). There is no significant association between ST-segment resolution and coronary TIMI flow grades. In patients with complete ST-segment resolution, 19 patients had TIMI III flow and 2 patients had TIMI II flow. In patients with incomplete ST-segment resolution, 72 patients had TIMI III flow, 6 patients had TIMI II flow; and 1 patient had no-reflow (P=0.84). Conclusion: Complete ST-segment resolution in post-primary PCI settings has no significant association with in-hospital mortality. Absent or incomplete ST-segment resolution is not necessarily an indicator of coronary artery re-occlusion after primary PCI
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