Geochronology of Massif-Type Anorthosites from the Ubendian Belt, Tanzania

Massif-type anorthosites occur in East Africa at the margins of the Tanzania Craton in the Ubendian Belt. The massif assemblage constitutes of mafic-composition plutons (meta-anorthosite and meta-gabbro), ultramafic plutons, and titaniferous iron-ore. Silicic ortho-gneisses (tonalitic, dioritic, and granodioritic intrusives) also occur in the vicinity of the said massif-type anorthosites. This article presents ages of meta-anorthosites and meta-gabbros. The new U-Pb zircon age indicates that meta-gabbros and meta-anorthosites crystallized between 1915 ± 24 and 1905 ± 24 Ma concomitantly with the silicic magmatic bodies. Geochronological databases indicate that the period between 1920 and 1850 Ma HP-LT metamorphic interface was formed at subduction zone settings in the Ubendian Belt along with emplacement of arc related voluminous batholiths and volcanic rocks. The subduction tectonics was probably a driving engine for magmatism in the region. A Neoproterozoic metamorphic event dated at 547 ± 25 Ma reworked the Ubendian Belt massifs-type anorthosites. Keywords: Ubendian Belt; massif-type Anorthosites; U-Pb zircon age

Geochemical Characterization of the Paleoproterozoic Massif-Type Anorthosites from the Ubendian Belt, Tanzania

Paleoproterozoic massif-type anorthosites occur in Southern Ubendian Belt (Upangwa Terrane) in Tanzania, mainly as mafic-plutons (meta-anorthosite and meta-gabbro) associated with ultramafic stocks and titaniferous magnetite bodies. Variably metamorphosed silicic granitoids are also recorded in the area. This article presents geochemical characteristics of meta-anorthosites, meta-gabbros and the associated granitoids in order to determine their genetic links and geotectonic settings. The meta-anorthosites, meta-gabbros and meta-tonalite have indistinguishable chondrite normalized REE patterns displaying LREE-enriched patterns (e.g., (La/Sm)N = 1.97–6.10) and negatively sloping HREE ((La/Yb)N = 4.05–47.06) suggesting continental crustal affinity. The trace element patterns of the studied meta-anorthosites are characterized by enrichments of Eu and Sr, which is a typical signature of plagioclase dominated cumulates. The MORB-normalized trace element patterns of meta-anorthosites and meta-gabbros resemble the average continental arc trace element patterns. Likewise, trace element ratios (e.g., Th/Yb and Nb/Yb) Upangwa Terrane plutons point to their crystallization at a continental arc probably between 1920 and 1850 Ma. Keywords: Ubendian Belt; Massif-type Anorthosites; Trace Element Geochemistry; Tanzania

Prevalence and risk factors associated with retinopathy in diabetic patients at Parirenyatwa Hospital outpatients’ clinic in Harare, Zimbabwe

Diabetic retinopathy is the fifth leading cause of blindness worldwide accounting for nearly 5% of all blindness. However, most of the prevalence and incidence data is from developed countries, with very limited information from sub-Saharan Africa. The study sought to determine the prevalence of, and factors associated with, retinopathy in diabetic patients. Diabetes mellitus patients attending the outpatients’ clinic at Parirenyatwa Group of Hospitals between October 2013 and July 2014 were recruited into this analytical cross-sectional study. Demographic information was collected. A nurse carried out anthropometric measurements. An ophthalmologist using slit lamp indirect ophthalmoscopy with a 20-diopter and a 90-diopter lens diagnosed retinopathy. Blood samples were collected and analysed for triglycerides, total cholesterol, HDL cholesterol, glycosylated hemoglobin and serum creatinine. A total of 340 patients were enrolled into the study, of whom 73.2% were female. Mean (SD) age was 57.5 (14.9) years and there was no difference in age between females [57.6 (14.1) years] and males [57.2 (16.8) years]. The overall prevalence of diabetic retinopathy was 28.4%. Using multivariate logistic regression analysis retinopathy was associated with longerduration of diabetes mellitus (OR 1.06, 95% CI 1.03-1.09, p value ˂ 0.001) and lower serum creatinine (OR 0.99, 95% CI 0.97-1.00, p value 0.025). The prevalence of diabetic retinopathy was 28.4%. Longer duration of diabetes mellitus and lower serum creatinine, which is a marker of renal damage, were independent risk factors of diabetic retinopathy.Keywords: Diabetes mellitus; Diabetic retinopathy; Complications; Blindness; Prevalence; Risk facto

Writing in Britain and Ireland, c. 400 to c. 800

No abstract available

Anti-Severe Acute Respiratory Syndrome Coronavirus 2 Immunoglobulin G Antibody Seroprevalence Among Truck Drivers and Assistants in Kenya.

In October 2020, anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunoglobulin G seroprevalence among truck drivers and their assistants (TDA) in Kenya was 42.3%, higher than among healthcare workers and blood donors. Truck drivers and their assistants transport essential supplies during the coronavirus disease 2019 pandemic, placing them at increased risk of being infected and of transmitting SARS-CoV-2 over a wide geographical area

Assessment of Solid Waste Management in Kinondoni Municipality

This study aimed to assess the Solid waste Management in Kinondoni Municipality in the year 2014. The sample comprised a total number of 50 households in which two wards of Sinza and Ubungo were purposively chosen to represent the rest of wards in Kinondono Municipality. Data on solid waste management were collected using direct observation, interview and questionnaires. Both descriptive and inferential statistics were used for data analysis. Data were analysed using Statistical Package for Social Sciences (SPSS) Version 16.0. Findings indicates that high solid waste are generated from the following sources households 80% (1618.8 t/day), informal sector waste 16% (322.2 t/day), market waste 2% (40.5 t/day) and commercial waste 1% (30.4 t/day). Furthermore, 76% of the respondents had no access to door to door solid waste collection services delivered by the municipality due to poor collection system (85%), poor road access (76%) and lack of community participation. Only 15% of the respondent had an acess to the service that collect and transfer their waste to disposal site. It can be concluded that, the overall solid waste management service is poor. Waste generated is in high quantity compared to the amount collected and transferred to disposal site. Insufficient methods of solid waste collection and transportation in kinondoni municipal are not improved and there is little access to municipal vehicle for solid waste transfer and transportation to the final disposal. It is recommended from this study that, for efficiency and effective solid waste management a cooperative effort involving all stakeholders, including citizens, businesses, community based organizations, nongovernmental organizations, government agencies, universities, and other research organizations is un avoidable

Pyruvate carboxylase : studies on the reaction mechanism / by Nelson Francis Boniface Phillips

Typescript (photocopy)vii, 148 leaves : ill. ; 30 cm.Thesis (Ph.D.)--University of Adelaide, Dept. of Biochemistry, 198