
University of Uyo
UniversityUyo, Nigeria
Research output, citation impact, and the most-cited recent papers from University of Uyo (Nigeria). Aggregated across the NobleBlocks index of 300M+ scholarly works.
Top-cited papers from University of Uyo
The drying of fruits and vegetables is a complex operation that demands much energy and time. In practice, the drying of fruits and vegetables increases product shelf-life and reduces the bulk and weight of the product, thus simplifying transport. Occasionally, drying may lead to a great decrease in the volume of the product, leading to a decrease in storage space requirements. Studies have shown that dependence purely on experimental drying practices, without mathematical considerations of the drying kinetics, can significantly affect the efficiency of dryers, increase the cost of production, and reduce the quality of the dried product. Thus, the use of mathematical models in estimating the drying kinetics, the behavior, and the energy needed in the drying of agricultural and food products becomes indispensable. This paper presents a comprehensive review of modeling thin-layer drying of fruits and vegetables with particular focus on thin-layer theories, models, and applications since the year 2005. The thin-layer drying behavior of fruits and vegetables is also highlighted. The most frequently used of the newly developed mathematical models for thin-layer drying of fruits and vegetables in the last 10 years are shown. Subsequently, the equations and various conditions used in the estimation of the effective moisture diffusivity, shrinkage effects, and minimum energy requirement are displayed. The authors hope that this review will be of use for future research in terms of modeling, analysis, design, and the optimization of the drying process of fruits and vegetables.
BACKGROUND: For more than three decades, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) has provided a framework to quantify health loss due to diseases, injuries, and associated risk factors. This paper presents GBD 2023 findings on disease and injury burden and risk-attributable health loss, offering a global audit of the state of world health to inform public health priorities. This work captures the evolving landscape of health metrics across age groups, sexes, and locations, while reflecting on the remaining post-COVID-19 challenges to achieving our collective global health ambitions. METHODS: The GBD 2023 combined analysis estimated years lived with disability (YLDs), years of life lost (YLLs), and disability-adjusted life-years (DALYs) for 375 diseases and injuries, and risk-attributable burden associated with 88 modifiable risk factors. Of the more than 310 000 total data sources used for all GBD 2023 (about 30% of which were new to this estimation round), more than 120 000 sources were used for estimation of disease and injury burden and 59 000 for risk factor estimation, and included vital registration systems, surveys, disease registries, and published scientific literature. Data were analysed using previously established modelling approaches, such as disease modelling meta-regression version 2.1 (DisMod-MR 2.1) and comparative risk assessment methods. Diseases and injuries were categorised into four levels on the basis of the established GBD cause hierarchy, as were risk factors using the GBD risk hierarchy. Estimates stratified by age, sex, location, and year from 1990 to 2023 were focused on disease-specific time trends over the 2010-23 period and presented as counts (to three significant figures) and age-standardised rates per 100 000 person-years (to one decimal place). For each measure, 95% uncertainty intervals [UIs] were calculated with the 2·5th and 97·5th percentile ordered values from a 250-draw distribution. FINDINGS: Total numbers of global DALYs grew 6·1% (95% UI 4·0-8·1), from 2·64 billion (2·46-2·86) in 2010 to 2·80 billion (2·57-3·08) in 2023, but age-standardised DALY rates, which account for population growth and ageing, decreased by 12·6% (11·0-14·1), revealing large long-term health improvements. Non-communicable diseases (NCDs) contributed 1·45 billion (1·31-1·61) global DALYs in 2010, increasing to 1·80 billion (1·63-2·03) in 2023, alongside a concurrent 4·1% (1·9-6·3) reduction in age-standardised rates. Based on DALY counts, the leading level 3 NCDs in 2023 were ischaemic heart disease (193 million [176-209] DALYs), stroke (157 million [141-172]), and diabetes (90·2 million [75·2-107]), with the largest increases in age-standardised rates since 2010 occurring for anxiety disorders (62·8% [34·0-107·5]), depressive disorders (26·3% [11·6-42·9]), and diabetes (14·9% [7·5-25·6]). Remarkable health gains were made for communicable, maternal, neonatal, and nutritional (CMNN) diseases, with DALYs falling from 874 million (837-917) in 2010 to 681 million (642-736) in 2023, and a 25·8% (22·6-28·7) reduction in age-standardised DALY rates. During the COVID-19 pandemic, DALYs due to CMNN diseases rose but returned to pre-pandemic levels by 2023. From 2010 to 2023, decreases in age-standardised rates for CMNN diseases were led by rate decreases of 49·1% (32·7-61·0) for diarrhoeal diseases, 42·9% (38·0-48·0) for HIV/AIDS, and 42·2% (23·6-56·6) for tuberculosis. Neonatal disorders and lower respiratory infections remained the leading level 3 CMNN causes globally in 2023, although both showed notable rate decreases from 2010, declining by 16·5% (10·6-22·0) and 24·8% (7·4-36·7), respectively. Injury-related age-standardised DALY rates decreased by 15·6% (10·7-19·8) over the same period. Differences in burden due to NCDs, CMNN diseases, and injuries persisted across age, sex, time, and location. Based on our risk analysis, nearly 50% (1·27 billion [1·18-1·38]) of the roughly 2·80 billion total global DALYs in 2023 were attributable to the 88 risk factors analysed in GBD. Globally, the five level 3 risk factors contributing the highest proportion of risk-attributable DALYs were high systolic blood pressure (SBP), particulate matter pollution, high fasting plasma glucose (FPG), smoking, and low birthweight and short gestation-with high SBP accounting for 8·4% (6·9-10·0) of total DALYs. Of the three overarching level 1 GBD risk factor categories-behavioural, metabolic, and environmental and occupational-risk-attributable DALYs rose between 2010 and 2023 only for metabolic risks, increasing by 30·7% (24·8-37·3); however, age-standardised DALY rates attributable to metabolic risks decreased by 6·7% (2·0-11·0) over the same period. For all but three of the 25 leading level 3 risk factors, age-standardised rates dropped between 2010 and 2023-eg, declining by 54·4% (38·7-65·3) for unsafe sanitation, 50·5% (33·3-63·1) for unsafe water source, and 45·2% (25·6-72·0) for no access to handwashing facility, and by 44·9% (37·3-53·5) for child growth failure. The three leading level 3 risk factors for which age-standardised attributable DALY rates rose were high BMI (10·5% [0·1 to 20·9]), drug use (8·4% [2·6 to 15·3]), and high FPG (6·2% [-2·7 to 15·6]; non-significant). INTERPRETATION: Our findings underscore the complex and dynamic nature of global health challenges. Since 2010, there have been large decreases in burden due to CMNN diseases and many environmental and behavioural risk factors, juxtaposed with sizeable increases in DALYs attributable to metabolic risk factors and NCDs in growing and ageing populations. This long-observed consequence of the global epidemiological transition was only temporarily interrupted by the COVID-19 pandemic. The substantially decreasing CMNN disease burden, despite the 2008 global financial crisis and pandemic-related disruptions, is one of the greatest collective public health successes known. However, these achievements are at risk of being reversed due to major cuts to development assistance for health globally, the effects of which will hit low-income countries with high burden the hardest. Without sustained investment in evidence-based interventions and policies, progress could stall or reverse, leading to widespread human costs and geopolitical instability. Moreover, the rising NCD burden necessitates intensified efforts to mitigate exposure to leading risk factors-eg, air pollution, smoking, and metabolic risks, such as high SBP, BMI, and FPG-including policies that promote food security, healthier diets, physical activity, and equitable and expanded access to potential treatments, such as GLP-1 receptor agonists. Decisive, coordinated action is needed to address long-standing yet growing health challenges, including depressive and anxiety disorders. Yet this can be only part of the solution. Our response to the NCD syndemic-the complex interaction of multiple health risks, social determinants, and systemic challenges-will define the future landscape of global health. To ensure human wellbeing, economic stability, and social equity, global action to sustain and advance health gains must prioritise reducing disparities by addressing socioeconomic and demographic determinants, ensuring equitable health-care access, tackling malnutrition, strengthening health systems, and improving vaccination coverage. We live in times of great opportunity. FUNDING: Gates Foundation and Bloomberg Philanthropies.
Why Evidence-Based Guidelines Are Urgently Needed Mental, neurological, and substance use (MNS) disorders are highly prevalent and are responsible for 14% of the global burden of disease expressed in disabilityadjusted life years (DALYs) The resources that have been provided in countries to tackle the huge burden are insufficient, inequitably distributed, and inefficiently used, which results in a large majority of people with these disorders receiving no care at all [2-7]. Even when available, treatment and care often is neither evidence-based nor of high quality. The result is a large treatment gap, with more than 75% in many low-and middleincome countries (LAMIC).
Adsorption of methylene blue from aqueous solution onto coconut coir dust (CCD) a low cost agricultural waste material in a batch process was investigated. Adsorption was studied as a function of amount of adsorbent, pH and concentration with time. It was found that percentage adsorption varied linearly with the amount of adsorbent and concentration with time but varies non-linearly with pH. Adsorption equilibrium data were represented by isotherm, kinetics and thermodynamics models. Three isotherm models namely Langmuir, Freundlich and Temkin were tested and adsorption was found to fit well into these models with R2 ⩾ 0.90. The kinetic data were well described by the pseudo-second order kinetic model. The adsorption process was endothermic with a mean change in enthalpy (ΔH) (+17.87 KJ mol−1) and spontaneous with a mean free energy change (ΔG) (−9.69 KJ mol−1). FTIR analyses of the adsorbent suggest that adsorption of the dye was through a chemical interaction of the functional groups on the surface of the adsorbent.
The main objective of this paper is to examine African culture and values. Since culture is often seen as the sum total of the peculiarities shared by a people, a people’s values can be seen as part of their culture. In discussing African culture and values, we are not presupposing that all African societies have the same explanation(s) for events, the same language, and same mode of dressing and so on. Rather, there are underlying similarities shared by many African societies which, when contrasted with other cultures, reveal a wide gap of difference. In this paper, we try to show the relevance of African culture and values to the contemporary society but maintain that these values be critically assessed, and those found to be inimical to the well-being and holistic development of the society, be discarded. In this way, African culture and values can be revaluated, their relevance established and sustained in order to give credence to authentic African identity.
CONTEXT: In animals, methamphetamine is known to have a neurotoxic effect on serotonin neurons, which have been implicated in the regulation of mood, anxiety, and aggression. It remains unknown whether methamphetamine damages serotonin neurons in humans. OBJECTIVE: To investigate the status of brain serotonin neurons and their possible relationship with clinical characteristics in currently abstinent methamphetamine abusers. DESIGN: Case-control analysis. SETTING: A hospital research center. PARTICIPANTS: Twelve currently abstinent former methamphetamine abusers (5 women and 7 men) and 12 age-, sex-, and education-matched control subjects recruited from the community. INTERVENTIONS: The brain regional density of the serotonin transporter, a structural component of serotonin neurons, was estimated using positron emission tomography and trans-1,2,3,5,6,10-beta-hexahydro-6-[4-(methylthio)phenyl]pyrrolo-[2,1-a]isoquinoline ([(11)C](+)McN-5652). Estimates were derived from region-of-interest and statistical parametric mapping methods, followed by within-case analysis using the measures of clinical variables. MAIN OUTCOME MEASURES: The duration of methamphetamine use, the magnitude of aggression and depressive symptoms, and changes in serotonin transporter density represented by the [(11)C](+)McN-5652 distribution volume. RESULTS: Methamphetamine abusers showed increased levels of aggression compared with controls. Region-of-interest and statistical parametric mapping analyses revealed that the serotonin transporter density in global brain regions (eg, the midbrain, thalamus, caudate, putamen, cerebral cortex, and cerebellum) was significantly lower in methamphetamine abusers than in control subjects, and this reduction was significantly inversely correlated with the duration of methamphetamine use. Furthermore, statistical parametric mapping analyses indicated that the density in the orbitofrontal, temporal, and anterior cingulate areas was closely associated with the magnitude of aggression in methamphetamine abusers. CONCLUSIONS: Protracted abuse of methamphetamine may reduce the density of the serotonin transporter in the brain, leading to elevated aggression, even in currently abstinent abusers.
Purpose To investigate the inhibitive effect of gum arabic (GA) for the corrosion of aluminium in alkaline (NaOH) medium and determine its adsorption characteristics. The present work is another trial to find a cheap and environmentally safe inhibitor for aluminium corrosion. Design/methodology/approach The inhibition efficiency (%I) has been evaluated using the hydrogen evolution (via the gasometric assembly) and the thermometric methods at 30 and 40°C. The concentrations of GA (inhibitor) used were 0.1‐0.5 g/l and the concentrations of NaOH (the corrodent) were 0.1‐2.5 M. The mechanism of adsorption inhibition and type of adsorption isotherms were proposed from the trend of inhibition efficiency with temperature, E a , Δ G ads and Q ads values. Findings GA inhibited the corrosion of aluminium in NaOH solutions. The inhibition efficiency increased with increase in GA concentration and with increase in temperature. Phenomenon of chemical adsorption is proposed for the inhibition and the process followed the Langmuir and Freundlich adsorption isotherms. The results obtained in this study for the %I were comparable for the two methods used and were corroborated by kinetic and thermodynamic parameters evaluated from the experimental data. Research limitations/implications Further investigations involving electrochemical studies such as polarization method will enlighten more on the mechanistic aspect of the corrosion inhibition. Originality/value This paper provides new information on the possible application of GA as an environmentally friendly corrosion inhibitor even in highly aggressive alkaline environments. It has not been published elsewhere.
Zebrafish ( Danio rerio ) associative responses are useful for pharmaceutical and toxicology screening, behavioral genetics, and discovering neural mechanisms involved in behavioral modulation. In novel environments, zebrafish swim to tank bottoms and dark backgrounds, behaviors attributed to anxiety associated with threat of predation. To examine possible genetic effects of inbreeding and segregation on this behavior, we compared Zebrafish International Resource Center (ZIRC) AB and WIK lines to zebrafish and GloFish® from a pet store (PETCO) in two qualitatively different novel environments: the dive tank and aquatic light/dark plus maze. Behavior was observed in the dive tank for 5 min, immediately followed by 5 min in the light/dark plus maze. Among strains, WIK spent more time in the dive tank top than AB (76 + 30 vs. 17 + 11 sec), and AB froze in the plusmaze center for longer than PETCO or GloFish® (162 + 61 vs. 72 + 29 or 27 + 27 sec). Further,behavior of zebrafish exposed for 3 min to 25 mg/L nicotine, desipramine, chlordiazepoxide,yohimbine, 100 mg/L citalopram, 0.05% DMSO, or 0.5% ethanol was compared to controls. Approximately 0.1% of drug is available in brain after such exposures. Desipramine or citalopram exposed fish spent more time in the dive tank top, and both reuptake inhibitors bound to serotonin transporters in zebrafish brain with high affinity (K i = 7 + 5 and 9 + 5 nM). In the plus maze, chlordiazepoxide, ethanol and DMSO-exposed fish crossed more lines and spent more time in white arms. Neither 25 mg/L nicotine nor yohimbine altered zebrafish behavior in novel environments, but nicotine was anxiolytic at higher doses. Overall, the light/dark plus maze and dive tank are distinct behavioral measures that are sensitive to treatment with anxiolytic compounds, but zebrafish line selection and solvents can influence baseline behavior in these tests.
The aim of this study was to evaluate the removal of Pb (II) and Ni (II) from untreated waste water using sugarcane bagasse and possible desorption of the metal ions from the adsorbent for effective re-use. The effects of pH (4-6), temperature (30−70 °C), contact time (30−150 min) and adsorbent dosage (0.3−0.7 g) were examined. Optimum conditions for the removal efficiencies of Pb (89.31 %) and Ni (96.33 %) were pH, 6.0; temperature, 30 °C; contact time, 90 min. and adsorbent dosage, 0.5 g. The maximum monolayer adsorption capacities of Pb (II) and Ni (II) were 1.61 mg/g and 123.46 mg/g respectively, by fitting the equilibrium data to the Langmuir isotherm model. Freundlich isotherm and pseudo second order kinetic models were best fitted for Pb (II) and Ni (II) uptake. Desorption of the metal ions from the metal-loaded bagasse was best performed by HNO3 with removal efficiency of 85.2 %. Therefore, sugarcane bagasse has a high potential for removal of heavy metals from waste water and can be re-used at any time after desorption without losing its efficiency.
Corrosion inhibition of mild steel in 1 M H2SO4 by leaves and stem extracts of Sida acuta was studied using chemical (weight loss and hydrogen evolution) and spectroscopic (AAS, FTIR and UV-V) techniques at 30–60 °C. It was found that the leaves and stem extracts of S. acuta inhibited the acid induced corrosion of mild steel. The inhibition efficiency increases with increase in concentration of the extracts but decrease with rise in temperature. Inhibitive effect was afforded by adsorption of the extracts’ components which was approximated by Freundlich adsorption isotherm. Inhibition mechanism is deduced from the temperature dependence of the inhibition efficiency and also from spectroscopic results.
A new phenanthroline derivative, 2-mesityl-1H-imidazo[4,5-f][1,10]phenanthroline (MEIP), was synthesized and characterized by elemental analysis, FT-IR, 1 HNMR, and 13 CNMR spectra. MEIP was evaluated as corrosion inhibitor for carbon steel in 0.5 M H 2 SO 4 solution using gravimetric and UV−visible spectrophotometric methods at 303−333 K. Results obtained show that MEIP is a good inhibitor for mild steel in H 2 SO 4 solution. The inhibition efficiency was found to increase with increase in MEIP concentration but decreased with temperature, which is suggestive of physical adsorption mechanism. Activation parameters and Gibbs free energy for the adsorption process using Statistical Physics were calculated and discussed. The UV−visible absorption spectra of the solution containing the inhibitor after the immersion of mild steel specimen indicate the formation of a MEIP-Fe complex. The calculations of global reactivity indices of MEIP such as the localization of frontier molecular orbitals, E HOMO, E LUMO, energy gap (Δ E ), dipole moment ( D ), hardness (η), softness (σ), the fractions of electrons transferred (Δ N ), electrophilicity index (ω), total energy change (Δ E T ), and Mulliken charge distributions together with local reactivity by means of Fukui indices were used to explain the electron transfer mechanism between the MEIP molecules and the steel surface. The quantum chemical calculations were performed at the density functional theory (DFT) level using B3LYP functional with the 6-31G (d) basis set for all atoms using Spartan’06 V112 program package.
Drying operations can help in reducing the moisture content of food materials for avoidance of microbial growth and deterioration, for shelf life elongation, to minimize packaging and improving storage for easy transportation. Thin-layer drying of materials is necessary to understand the fundamental transport mechanism and a prerequisite to successfully simulate or scale up the whole process for optimization or control of the operating conditions. Researchers have shown that to rely solely on experimental drying practices without mathematical considerations for the drying kinetics, can significantly affect the efficiency of dryers, increase the cost of production, and reduce the quality of the dried product. An effective model is necessary for the process design, optimization, energy integration and control; hence, the use of mathematical models in finding the drying kinetics of agricultural products is very important. The statistical criteria in use for the evaluation of the best model(s) has it that coefficient of determination (R2) has to be close to unity while the rest statistical measures will have values tending to zero. In this work, the essence of drying using thin-layer, general approaches to modeling for food drying mechanisms thin layer drying models and optimization of the drying processes have been discussed.
OBJECTIVE: Antimicrobial stewardship is one of the strategic objectives of the WHO global action plan on antimicrobial resistance. This paper sought to review the extent of implementation of antimicrobial stewardship programmes (ASPs) in African countries and the reported outcomes. METHODS: We searched five electronic databases, including PubMed, Scopus, Cochrane library, African Journal Online, CINAHL and Google scholar for papers published between 1990 and March 2019. We combined the names of countries in the five regions of Africa with antimicrobial stewardship terms. Studies of any design, employing any stewardship strategies were included. The quality of included studies was assessed using the National Heart, Lung and Blood Institute (NHLBI) quality assessment tool for before and after studies. RESULTS: Of 1752 titles identified, 13 studies met the criteria for inclusion. Seven of the studies were conducted in South Africa, three in Kenya and one each in Sudan, Tanzania and Egypt. Eleven studies were of high quality with low risk of bias. The included studies mainly assessed the outcome using process measures and these were associated with improved compliance with antibiotic guidelines, appropriateness of prescribing, reduction in antibiotic use and cost savings. Decrease in rate of surgical site infections and nonsignificant change in mortality and 30-day readmission rate were reported in two studies respectively. CONCLUSION: Findings of this review show the paucity of data on implementation of ASPs in African countries. Although the continent is faced with challenges which impact on effective implementation of ASPs, the successes reported in the included studies show that other African countries can implement these programmes.
This paper applies a Multivariate Vector Error Correction (VECM) framework to examine the long run and causal relationship between electricity consumption, carbon emissions and economic growth in Nigeria. Using annual time series data for 1970 to 2008, findings show that in the long run, economic growth is associated with increase carbon emissions, while an increase in electricity consumption leads to an increase in carbon emissions. These imply that Nigeria’s growth process is pollution intensive, while the negative relationship between electricity consumption (or positive relationship between electricity consumption) and emissions in Nigeria is a clear indication that electricity consumption in the country has intensified carbon emissions. No support was obtained for the hypothesized environmental Kuznets curve (EKC). Granger-causality results confirm a unidirectional causality running from economic growth to carbon emissions, indicating that carbon emissions reduction policies could be pursued without reducing economic growth in Nigeria. No causality was found between electricity and growth, in either way, which further lends credence to the crisis in the Nigerian electricity sector. Overall, the paper submits that efficient planning and increased investment in electricity infrastructure development may be the crucial missing variable in the obtained neutrality hypothesis between electricity and growth.
The enormous amount of wastes produced during wood processing operations in many countries provides challenging opportunities for the use of wood waste as a construction material. In this research, wood waste (sawdust and wood shaving) ash (WWA) of pretreated timber of 0, 5, 10, 15, 20, 25, and 30% by weight of cement was added as a supplement to a concrete of mix proportion 1:2:4:0.56 (cement:sand:coarse aggregate:water cement ratio), and the strengths and the water absorption of the matrix were evaluated. Also, the metal leachability of WWA was analyzed. The compressive and the flexural strengths of WWA concrete for the ages investigated ranged from 12.83to28.66N∕mm2 , and 3.65to5.57N∕mm2 , respectively, with the lowest values obtained at 30% additive level of ash. When compared with the strength of plain concrete (control), the compressive and flexural strengths of WWA concrete were between 62 and 91% and 65 and 98%, respectively, of the former. The trend of the water absorption of WWA concrete was a reversal of those of the strengths, that is, the highest water absorption values were recorded for concrete specimens with the highest additive level of ash. A batch leaching test also performed at an ash-leachant volumetric ratio of 20 produced leachate containing chromium, arsenic, iron, copper, and zinc at the following concentrations: 410, 6720, 150, 280, and 1690μg∕L , respectively, when leached at a pH of 4, and 400, 10,670, 0, 100, 1470μg∕L , respectively, when leached at a pH of 5. These concentration levels exceed the EPA fresh water acute criteria limits.
Mycotoxin contamination of foods from mycotoxigenic fungi such as Aspergillus, Alternaria, Fusarium and Penicillium spp. is a significant threat to food safety and quality. Aflatoxins, ochratoxins, fumonisins, deoxynivalenol, zearalenone, trichothecenes and patulin have been demonstrated to show immune toxicity, carcinogenicity, nephrotoxicity, hepatotoxicity, neurotoxicity and teratogenicity activities in humans and animals. Implementation of the prerequisite programs like the HACCP-based procedures can reduce mycotoxin contamination, while conventional chemical, biological and physical methods can be employed for detoxification after contamination. But the increasing fungal resistance and challenges associated with the conventional systems necessitate the development of innovative strategies for rapid elimination with short processing time and negligible impact on quality. This review evaluated recent innovative strategies of cold atmospheric plasma (CAP), polyphenols and flavonoids, magnetic materials and nanoparticles and natural essential oils (NEOs) for controlling mycotoxin in foods. Although the available studies indicated the promising potential of these strategies, complete decontamination was not achieved. The mechanisms for the reduced bioactivity of mycotoxins included the disruption of fungal cell membrane and structural degradation of complex biochemical molecules by the oxidative effects of reactive species, inhibition of enzymes responsible for breakdown of carbohydrates and adsorption and binding of functional groups of mycotoxins in food substrate. Integrated management systems of combining multiple strategies can be explored for achieving higher efficiency and better adaptability to different food matrices. Additional studies on the toxicity of the food matrices, degraded products and industrial up-scaling are necessary for ensuring widespread adoption and cost-effective commercialisation for sustainable food processing.
INTRODUCTION: The widespread use of antiretroviral therapies (ART) has increased life expectancy in HIV patients, predisposing them to chronic non-communicable diseases including Chronic Kidney Disease (CKD). We performed a systematic review and meta-analysis (PROSPERO registration number CRD42016036246) to determine the global and regional prevalence of CKD in HIV patients. METHODS: We searched PubMed, Web of Science, EBSCO and AJOL for articles published between January 1982 and May 2016. CKD was defined as estimated glomerular filtration rate (eGFR) <60ml/min using the MDRD, Cockcroft-Gault or CKD-EPI equations. Random effects model was used to combine prevalence estimates from across studies after variance stabilization via Freeman-Tukey transformation. RESULT: Sixty-one eligible articles (n = 209,078 HIV patients) in 60 countries were selected. The overall CKD prevalence was 6.4% (95%CI 5.2-7.7%) with MDRD, 4.8% (95%CI 2.9-7.1%) with CKD-EPI and 12.3% (95%CI 8.4-16.7%) with Cockcroft-Gault; p = 0.003 for difference across estimators. Sub-group analysis identified differences in prevalence by WHO region with Africa having the highest MDRD-based prevalence at 7.9% (95%CI 5.2-11.1%). Within Africa, the pooled MDRD-based prevalence was highest in West Africa [14.6% (95%CI 9.9-20.0%)] and lowest in Southern Africa (3.2%, 95%CI 3.0-3.4%). The heterogeneity observed could be explained by WHO region, comorbid hypertension and diabetes mellitus, but not by gender, hepatitis B or C coinfection, CD4 count or antiretroviral status. CONCLUSION: CKD is common in HIV-infected people, particularly in Africa. HIV treatment programs need to intensify screening for CKD with added need to introduce global guidelines for CKD identification and treatment in HIV positive patients.
Some properties of concrete with sawdust ash (SDA) as a replacement for ordinary portland cement (OPC) are investigated. The compressive strength of specimens with replacement levels ranging from 10 to 30% cured for periods of 3–90 days showed a decreasing strength with higher ash content. The 28-day split tensile strength of SDA concrete specimens showed a similar trend. The SDA concrete was observed to gain rapid strength at later ages, indicating a pozzolanic activity of the ash. Although only concrete with a 10% replacement level attained the 20 N/mm2 designed strength at 28 days, test results indicate that SDA concrete can attain the same order of strength as conventional concrete at longer curing periods.
BACKGROUND: Although there is considerable public concern about the environmental impacts of oil pollution in the Niger Delta of Nigeria, actual evidence on the pathological and psychological effects in the health of local communities is minimally known. We sought to associate the perspective measures of exposure to oil pollution with health outcomes (inventory of health symptoms and functional capacity limitations) and determine how emotional reactions to environmental risks moderate these health outcomes. METHOD: The study was conducted with 600 participants selected from five local government areas in Akwa Ibom State where oil pollution is rampant. A structured questionnaire was used to collect the data on the respondents' exposure to oil pollution, self-rated health and disease symptoms, perception of risk of exposure and emotional reactions to local oil pollution. RESULTS: Most of the participants lived in areas with visible oil pollution and/or near gas flaring facilities and regularly suffered direct exposure to oil in their environment. High level of emotional distress was a part of everyone's life for the study population. Risk perception in the study area was mediated, to a large extent, by dreaded hazards (catastrophic fears of pipeline explosions and oil spill fire), visual cues (gas flares and smoke stacks) and chemosensory cues (off-flavor in drinking water). The exposure metrics were found to be significant predictors of the health effects and influencing factors (emotional reactions). Multi-levels models suggest that at the individual level, the demographic variables and direct contact with oil pollution were important mediators of functional capacity limitation. At the community level, emotional distress from fear of the sources of exposure was an important mediator of the health symptoms. CONCLUSIONS: This study documents high levels of disease symptoms and environmental distress (worry, annoyance and intolerance) associated with oil pollution in the Niger Delta areas of Nigeria. It highlights the need for some intervention to ameliorate the psychological distress associated with living under such environmental adversity.