363 research outputs found
Sea floor bedforms and their influence on slope accommodation (2019)
We sincerely thank Petroleum Geo-Services (PGS) Investigação Petrolífera Limitada, and specifically David Hajovsky and Scott Opdyke, that kindly provided the dataset and allowed us to show these results. We would also like to thank Schlumberger for providing academic licenses of their software (Petrel). We are grateful to Associate Editor Kei Ogata for his support, and we sincerely thank reviewers Daniele Casalbore and Kamaldeen Omosanya for their comments and suggestions that significantly improved the quality of the manuscript.Peer reviewedPostprin
Emulsifying and Suspending Properties of Enterolobium cyclocarpum Gum
Background:The thermodynamic instability of emulsions and suspensions necessitate the incorporation of emulsifiers and suspending agents respectively, in order to stabilize the formulations and ensure administration of accurate doses.Objective:Enterolobium cyclocarpum gum was characterized and evaluated for its emulsifying and suspending properties in comparison with official acacia gum.Method:Physicochemical and phytochemical characterization of Enterolobium cyclocarpum gum (ENCG) were carried out. Emulsifying properties were assessed using creaming rate, globule-size distribution and viscosity measurements. Metronidazole suspensions containing 1.0 -5.0%w/v of ENCG (or acacia) were assessed by sedimentation volume, pH determinations, viscosity and flow rate. Primary emulsions containing ENCG (or acacia) were formulated. Polysorbate-80 was also incorporated in the formulations to enhance the surface activity of the system.Results:ENCG contains anthraquinones, cardiac glycosides and flavonoids. It is a highly viscous, weakly acidic gum (pH 5.96 at 250C), with a high hydration power and swelling index of 15.14. Acacia emulsions were more stable than ENCG emulsions, however, polysorbate-80 at 8.95 %v/v, reduced the creaming rate of the emulsions. Globule size and viscosity (250C) ranked ENCG emulsions > acacia emulsions. Sedimentation volume decreased over time with ENCG suspensions demonstrating faster sedimentation rate. The pH of the suspensions remained relatively unchangedSuspensions containing ENGG were more viscous and the flow rates ranked ENCG suspensions < acacia emulsions.Conclusion:The results suggest that Enterolobium cyclocarpum gum is a highly viscous, poorly emulsifying gum but it hassuspending properties comparable with official acacia gum.Keywords: Enterolobium cyclocarpum, Emulsions, Suspensions, Pharmaceutical excipients
Health insurance coverage and modern contraceptive use among sexually active women in Nigeria: Further analysis of 2018 Nigeria Demographic Health Survey.
Studies have shown that affordable health insurance can influence healthcare visits and increase the choice of medication uptake in sub-Saharan Africa. However, there is a need to document the influence of health insurance coverage and modern contraceptive use in order to encourage its uptake. Thus, this study examined the influence of health insurance coverage on modern contraceptive use among sexually active women in Nigeria. The secondary dataset utilised in this study were derived from the 2018 Nigeria Demographic and Health Survey (NDHS). Data analyses were restricted to 24,280 women of reproductive age 15-49 years who were sexually active in the survey dataset. Weighted bivariate and multivariable logistic regression models were used to examine the influence of health insurance coverage on modern contraceptive use while controlling for possible confounders. A Significant level of alpha was determined at p < 0.05 using STATA 16.0. The prevalence of health insurance coverage and modern contraceptive use among sexually active women in Nigeria were 25.47% and 13.82%, respectively. About 1 out of every 4 sexually active women covered by health insurance were using a modern contraceptive, while 86.50% of the women not covered by health insurance were not using any modern contraceptive method. After adjusting for socio-demographic characteristics, the odds of using any modern contraceptive were significantly higher for sexually active women who were covered by any health insurance [aOR = 1.28; 95% (CI = 1.01-1.62)] compared to sexually active women not covered by health insurance in Nigeria. The study demonstrated that health insurance coverage is a significant driver of health service utilization, including modern contraceptive use. Health insurance benefits are recommended to be expanded to cover a broader spectrum of family planning services in Nigeria. More research is required to understand the influence of different health insurance schemes and the use of modern family planning methods in Nigeria. [Abstract copyright: © 2022. The Author(s).
Ultrastructural studies of acrosomal formation in the testis of male greater cane rat (Thryonomys swinderianus)
Purpose: In furthering the understanding of the process of spermatogenesis in the greater cane rat, this study describes the ultrastructural spermiogenic transformation and acrosomal formation in the testes of this hystricomorphic rodent that is currently undergoing domestication in parts of West Africa. Materials and Methods: Testicular samples were obtained from ten sexually mature cane rats that were perfused-fixed using Karnovsky\u27s fixative (phosphate buffered 2% paraformaldehyde – 2.5% glutaraldehyde fixative at pH 7.4). The samples were processed for ultrastructural analysis and examined under the transmission electron microscope. Results: The testes of the cane rat showed uniqueness in its cellular associations and the ultrastructure of the spermatogenic cells especially in the formation of the acrosome. The spermatid differentiation and acrosomal formation occurred in 12 steps with the first three steps being the Golgi phase and the next three steps making up the cap phase. While the three steps that follow constitute the acrosomal phase, the last 3 steps make up the maturation phase. At the cap and acrosomal phases, the entire acrosomal system comprising the vesicle and granule covers the head of the spermatids with no clear indentation of the nuclear surface by the formed acrosome. Furthermore, elongated spermatids at the maturation phase contained abundance of nuclear vacuoles. Conclusion: This work has not only provided information that will further the understanding of spermatogenesis but also aid the understanding of acrosomal reaction in the reproduction of the greater cane rat
Screening of effective electrolyte additives for zinc-based redox flow battery systems
This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this record.The purpose of this work is to assess the suitability of potential electrolyte additives for
zinc morphology control and improved electrochemical performance of the zinc electrode for
application in zinc based redox flow battery (RFB) systems. Based on existing literature in
the field, sixteen candidates are selected, including four metallic additives, two non-ionic
surfactants and ten quaternary ammonium compounds. The electrochemical performance of
the zinc electrode is assessed using cyclic voltammetry, linear sweep voltammetry and zinc
half-cell cycling tests using chronopotentiometry. Zinc electrodepositions are carried out
using chronopotentiometry in order to assess the effect of additives on zinc morphology with
scanning electron microscopy. Based on zinc reduction and oxidation reaction potentials, the
cycling efficiencies, and the effect on zinc morphology, the most promising additives of those
tested are tetraethylammonium hydroxide and tetraethylammonium bromide. Both provide
smooth and compact zinc deposits and zinc electrode coulombic efficiencies of 95-97 %
without leading to significant changes in the zinc reduction/oxidation overpotentials, yielding anodic and cathodic current densities of 77-78 mA cm-2 and 31-32 mA cm-2 at overpotentials of +/- 50 mV, respectively. In a zinc-nickel flow cell, these additives provide energy efficiencies of 78-79 %, compared with 69 % without an additive.This work was supported by the EPSRC Supergen Energy Storage Project (grant number: EP/P003494/1) entitled ‘Zinc-Nickel Redox Flow Battery for Energy Storage’; the EPSRC PhD studentship as a Doctoral Training Partnership (DTP); and the support from the College of Engineering, Mathematics and Physical Sciences in the University of Exeter
MICROBIOLOGICAL AND NUTRITIONAL QUALITY OF KUNU-ZAKI MADE FROM DIFFERENT GRAINS
Evaluation was made of the microbial profile and nutritional content of Kunu zaki prepared from different grains and their combinations; Millet only, White Sorghum only, Maize only, Red Sorghum only, Millet and Maize (1:1), Sorghum and Maize (1:1) and Sorghum and Millet (1:1). Total Aerobic Plate Count (TAPC) of the samples ranged from 2.0×103 - 1.4×105cfuml-1, Coliform Count (CC) ranged from 2.0 × 103 - 2.2×105 cfuml-1 and Fungal Count (FC) was 2.0× 103 – 6.0× 104 cfuml-1). The pH values ranged from 3.55 - 3.92. The proximate composition of the Kunun-zaki prepared from the different grains ranged from 83.74 - 88.39% for moisture content, 0.28 - 0.45% for protein, 0.38 - 1.35% for Crude fat, 0.001 - 0.010% for Crude fibre, 9.99 - 14.86% for Carbohydrate and 0.12 - 0.73% for Total ash content. Bacteria isolated from the various Kunu zaki samples were Bacillus subtilis, Escherichia coli, Staphyloccocus aureus, species of Klebsiella, Lactobacillus and Shigella. The fungi isolated include Aspergillus fumigatus, Aspergillus niger, species of Cephalosporium, Mucor and Penicillum. Kunun-zaki is a refreshing drink produced by natural unclassified array of microorganisms some of which could be pathogenic. The need to employ HACCP, GMP during production and development of starter culture is advocated
Potential of Indigenous Vegetable-Fortified Food Products for Improved Human Nutrition and Health in West Africa
The study developed and tested the acceptability of key innovative value-added products, including vegetable-fortified bread and pastry products (cookies and chinchin), using each of these three indigenous vegetables, namely Telfairia occidentalis Hook. F. (fluted pumpkin), Amaranthus virdis L. (local amaranth), and Solanum macrocarpon L. (eggplant). The bread was fortified with each of the individual dried leafy vegetables at levels of 1%, 3%, and 5%. Ogi was also fortified with the equivalent of the dried Telfaria occidentalis in the wet form at 1%, 3%, and 5%, while pastry was fortified with the only extract obtained from amaranth leafy vegetable at 1%, 3%, and 5%. Results from the MicroVeg project showed that bread fortified with 3% (w/w) dried vegetable leaf powders had higher nutritional properties. Pastry formulations that included 3% dried vegetable leaf powders had slightly lower consumer acceptability in terms of taste and color; however, due to the associated potential health benefits, consumers were willing to buy the vegetable-fortified products as replacements for the regular products. This chapter discusses the full details of the nutrition and value addition aspects of MicroVeg with empirical examples of the interventions and the potential contributions to dietary diversity and enhanced family nutrition
Chemical Composition and Quality Characteristics of Wheat Bread Supplemented with Leafy Vegetable Powders
The study investigated the effect of supplementation of the leaf powders of Telfairia occidentalis, Amaranthus viridis, and Solanum macrocarpon on the chemical composition and the quality characteristics of wheat bread. The bread samples were supplemented with each of the vegetable leaf powders at 1%, 2%, and 3% during preparation. The bread samples were assayed for proximate composition, mineral composition, physical, sensory, and antioxidant properties using standard methods. The addition of vegetable powders significantly increased the protein (9.50 to 13.93%), fibre (1.81 to 4.00%), ash (1.05 to 2.38%), and fat (1.27 to 2.00%). Supplementation with vegetable powder however significantly decreased (p<0.05) the carbohydrate and moisture contents. Significant (p<0.05) increases were recorded for all evaluated minerals as the level of vegetable powder increased. Supplementation with vegetable powder caused significant decrease in total phenolic content, percentage DPPH inhibition, metal chelating ability, ferric reducing antioxidant power, and total antioxidant capacity. Sensory results showed that there was significant decrease in sensory qualities with increasing supplementation. This therefore suggests that bread supplemented with vegetable powder could have more market penetration if awareness is highly created
Clinical use of HIV integrase inhibitors : a systematic review and meta-analysis
Background: Optimal regimen choice of antiretroviral therapy is essential to achieve long-term clinical success. Integrase inhibitors have swiftly been adopted as part of current antiretroviral regimens. The purpose of this study was to review the evidence for integrase inhibitor use in clinical settings.
Methods: MEDLINE and Web-of-Science were screened from April 2006 until November 2012, as were hand-searched scientific meeting proceedings. Multiple reviewers independently screened 1323 citations in duplicate to identify randomized controlled trials, nonrandomized controlled trials and cohort studies on integrase inhibitor use in clinical practice. Independent, duplicate data extraction and quality assessment were conducted.
Results: 48 unique studies were included on the use of integrase inhibitors in antiretroviral therapy-naive patients and treatment-experienced patients with either virological failure or switching to integrase inhibitors while virologically suppressed. On the selected studies with comparable outcome measures and indication (n = 16), a meta-analysis was performed based on modified intention-to-treat (mITT), on-treatment (OT) and as-treated (AT) virological outcome data. In therapy-naive patients, favorable odds ratios (OR) for integrase inhibitor-based regimens were observed, (mITT OR 0.71, 95% CI 0.59-0.86). However, integrase inhibitors combined with protease inhibitors only did not result in a significant better virological outcome. Evidence further supported integrase inhibitor use following virological failure (mITT OR 0.27; 95% CI 0.11-0.66), but switching to integrase inhibitors from a high genetic barrier drug during successful treatment was not supported (mITT OR 1.43; 95% CI 0.89-2.31). Integrase inhibitor-based regimens result in similar immunological responses compared to other regimens. A low genetic barrier to drug-resistance development was observed for raltegravir and elvitegravir, but not for dolutegravir.
Conclusion: In first-line therapy, integrase inhibitors are superior to other regimens. Integrase inhibitor use after virological failure is supported as well by the meta-analysis. Careful use is however warranted when replacing a high genetic barrier drug in treatment-experienced patients switching successful treatment
Effects of Externally Rated Job Demand and Control on Depression Diagnosis Claims in an Industrial Cohort
This study examined whether externally rated job demand and control were associated with depression diagnosis claims in a heavy industrial cohort. The retrospective cohort sample consisted of 7,566 hourly workers aged 18–64 years who were actively employed at 11 US plants between January 1, 1996, and December 31, 2003, and free of depression diagnosis claims during an initial 2-year run-in period. Logistic regression analysis was used to model the effect of tertiles of demand and control exposure on depression diagnosis claims. Demand had a significant positive association with depression diagnosis claims in bivariate models and models adjusted for demographic (age, gender, race, education, job grade, tenure) and lifestyle (smoking status, body mass index, cholesterol level) variables (high demand odds ratio = 1.39, 95% confidence interval: 1.04, 1.86). Control was associated with greater risk of depression diagnosis at moderate levels in unadjusted models only (odds ratio = 1.47, 95% confidence interval: 1.12, 1.93), while low control, contrary to expectation, was not associated with depression. The effects of the externally rated demand exposure were lost with adjustment for location. This may reflect differences in measurement or classification of exposure, differences in depression diagnosis by location, or other location-specific factors
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