Africa Centres of Excellence Scholarly Output

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A 2-hop LoRa Approach Based on Smart and Transparent Relay-Device
(Springer Nature, Switzerland, 2019) Diop, Mamour; Pham, Congduc; Thiare, Ousmane
LoRa is designed for long-range communication where devices are directly connected to the gateway, which removes typically the need of constructing and maintaining a complex multi-hop network. Nonetheless, even with the advantage of penetration of walls, the range may not sometimes be sufficient. This article describes a 2-hop LoRa approach to reduce both packet losses and transmission cost. To that aim, we introduce a smart, transparent and battery-operated relay-devicethat can be added after a deployment campaign to seamlessly provide an extra hop between the remote devices and the gateway. Field tests were conducted to assess relays’ ability to automatically synchronize to the network without advertising their presence.
4-index theory of gravity
(arXiv, 2019-01-16) Moradpour, H.; Licata, I.; Corda, C.; Salako, Ines G.
Recently, a 4-index generalization of the Einstein theory is proposed by Moulin [1]. Using this method, we find the most general 2-index field equations derivable from the Einstein-Hilbert action. The application of Newtonian limit, the role of gravitational coupling constant and the effects of the properties of ordinary energy-momentum tensor in obtaining a 4-index gravity theory have been studied. We also address the results of building Weyl free 4-index gravity theory. Our study displays that both the Einstein and Rastall theories can be obtained as the subclasses of a 4-index gravity theory which shows the power of 4-index method in unifying various gravitational theories. It is also obtained that the violation of the energy-momentum conservation law may be allowed in 4-index gravity theory, and moreover, the contraction of 4-index theory generally admits a non-minimal coupling between geometry and matter field in the Rastall way. This study also shows that, unlike the Einstein case, the gravitational coupling constant of 4-index Rastall theory generally differs from that of the ordinary 2-index Rastall theory.
Acceptability of Babies Conceived through Assisted Reproductive Technology among Married Women in University of Benin Teaching Hospital, Benin City, Nigeria
(CHRISMED Journal of Health and Research, 2021-01-25) Olorunfemi, Olaolorunpo; Osian, Eunice Amaechi; Oahimijie, Florence Onyemaechi
Infertility is a condition whereby a married woman is unable to et pregnant despite having frequent unprotected sex for at least a year. This has been an area of medicine in which health care practitioners has limited means to help their patients. The landscape of this fields changed dramatically with the announcement of birth through the of Assisted Reproductive Technology (ART) by Louise Brown in 1978. This has given hope to millions of couples suffering from infertility
Acceptability of mentor mother peer support for women living with HIV in North-Central Nigeria: a qualitative study
(Spinger Nature, 2021-08-07) Odiachi, Angela; Al‑Mujtaba, Maryam; Torbunde, Nguavese
Background Mentor mothers provide psychosocial and other support to pregnant and post-partum women living with HIV (WLHIV), which has been shown to enhance maternal-infant outcomes in the prevention of mother-to-child transmission of HIV (PMTCT). Our objective was to assess the acceptability of mentor mothers as a PMTCT intervention, and to explore opinions on mentor mother program composition and delivery among stakeholders in North-Central Nigeria. Methods We conducted nine focus group discussions and 31 in-depth interviews with 118 participants, including WLHIV, pregnant women, male partners, health workers, traditional birth attendants, community leaders, PMTCT program implementers, and policymakers. Participants were purposively recruited from health facilities and surrounding communities in the Federal Capital Territory and Nasarawa State. Transcripts were manually analysed using a Grounded Theory approach, where theory was derived from the data collected. Results Most participants were female (n = 78, 67%), and married (n = 110, 94%). All participant groups found mentor mothers acceptable as women providing care to pregnant and postpartum women, and as WLHIV supporting other WLHIV. Mentor mothers were uniquely relatable as role models for WLHIV because they were women, living with HIV, and had achieved an HIV-negative status for their HIV-exposed infants. Mentor mothers were recognized as playing major roles in maternal health education, HIV treatment initiation, adherence, and retention, HIV prevention for male partners and infants, and couple HIV disclosure. Most WLHIV preferred to receive mentor mothers’ services at health facilities rather than at home, due to concerns about HIV-related stigma and discrimination through association with mentor mothers. Key mentor mother needs were identified as training, remuneration, and validation as lay health workers. Conclusions Mentor mothers are an acceptable PMTCT intervention among stakeholders in North-Central Nigeria. However, stigma and discrimination for both mentor mothers and their clients remain a critical challenge, and mentor mother needs such as training, pay, and a sustainably supported niche in health systems require focused attention.
Access to antivenoms in the developing world: A multidisciplinary analysis
(2021-11-01) Potet, Julien; Beran, David; Ray, Nicolas
Access to safe, effective, quality-assured antivenom products that are tailored to endemic venomous snake species is a crucial component of recent coordinated efforts to reduce the global burden of snakebite envenoming. Multiple access barriers may affect the journey of antivenoms from manufacturers to the bedsides of patients. Our review describes the antivenom ecosystem at different levels and identifies solutions to overcome these challenges. At the global level, there is insufficient manufacturing output to meet clinical needs, notably for antivenoms intended for use in regions with a scarcity of producers. At national level, variable funding and deficient regulation of certain antivenom markets can lead to the procurement of substandard antivenom. This is particularly true when producers fail to seek registration of their products in the countries where they should be used, or where weak assessment frameworks allow registration without local clinical evaluation. Out-of-pocket expenses by snakebite victims are often the main source of financing antivenoms, which results in the underuse or under-dosing of antivenoms, and a preference for low-cost products regardless of efficacy. In resource-constrained rural areas, where the majority of victims are bitten, supply of antivenom in peripheral health facilities is often unreliable. Misconceptions about treatment of snakebite envenoming are common, further reducing demand for antivenom and exacerbating delays in reaching facilities equipped for antivenom use. Multifaceted interventions are needed to improve antivenom access in resource-limited settings. Particular attention should be paid to the comprehensive list of actions proposed within the WHO Strategy for Prevention and Control of Snakebite Envenoming.
Activity of Compounds from Temperate Propolis against Trypanosoma brucei and Leishmania mexicana
(MDPI, 2021-06-26) Alotaibi, Adullah; Ebiloma, Godwin U.; Williams, Roderick
Ethanolic extracts of samples of temperate zone propolis, four from the UK and one from Poland, were tested against three Trypanosoma brucei strains and displayed EC50 values < 20 g/mL. The extracts were fractionated, from which 12 compounds and one two-component mixture were isolated, and characterized by NMR and high-resolution mass spectrometry, as 3-acetoxypinobanksin, tectochrysin, kaempferol, pinocembrin, 40-methoxykaempferol, galangin, chrysin, apigenin, pinostrobin, cinnamic acid, coumaric acid, cinnamyl ester/coumaric acid benzyl ester (mixture), 40,7- dimethoxykaempferol, and naringenin 40,7-dimethyl ether. The isolated compounds were tested against drug-sensitive and drug-resistant strains of T. brucei and Leishmania mexicana, with the highest activities 15 M. The most active compounds against T. brucei were naringenin 40,7 dimethyl ether and 40methoxy kaempferol with activity of 15–20 M against the three T. brucei strains. The most active compounds against L. mexicana were 40,7-dimethoxykaempferol and the coumaric acid ester mixture, with EC50 values of 12.9 3.7 M and 13.1 1.0 M. No loss of activity was found with the diamidine- and arsenical-resistant or phenanthridine-resistant T. brucei strains, or the miltefosineresistant L. mexicana strain; no clear structure activity relationship was observed for the isolated compounds. Temperate propolis yields multiple compounds with anti-kinetoplastid activity.
Actualisation de la distribution géographique des cercosporioses des bananiers en Côte d’Ivoire : diversité et incidence de l’agent pathogène
(Journal of Applied Biosciences, 2021-10) Tou, Seydou; CAMARA, Brahima; Kassi, Koffi Fernand Jean-Martial
Les cercosporioses noire et jaune causées respectivement par les champignons ascomycètes Mycosphaerella fijiensis et Mycosphaerella musicola sont les maladies foliaires les plus dévastatrices en culture du bananier. La cercosporioses noire ou maladie des raies noires (MRN) est considérée comme la plus contraignante et se traduit par des pertes de rendement allant de 30 à 80 %. La présente étude se propose d’actualiser la carte de distribution géographique des cercosporioses noire et jaune en Côte d’Ivoire par l’évaluation sanitaire des bananeraies dans les principales zones de production et de caractériser la variabilité des isolats de Mycosphaerella spp. isolés. Méthodologie et résultats : Pour se faire, des prospections ont été effectuées pendant 3 années successives dans des zones préalablement sélectionnées de production de banane dessert ou de banane plantain sur la base de la diversité des conditions écologiques et la facilité d’accès. Les paramètres phytopathologiques observées pendant ces prospections ont été la plus jeune feuille touchée par la maladie (PJFT), la plus jeune feuille nécrosée (PJFN) et le nombre de feuilles vivantes (NFV) sur les bananiers. Les résultats ont montré que la cercosporiose noire est bien établie dans toutes les plantations prospectées soit 100 % et que la cercosporiose jaune est présente seulement dans 3 zones agro-écologiques (ZAE II, ZAE III et ZAE IV), soit 8,79 % des plantations prospectées. La sévérité des attaques dues à Mycosphaerella spp. a varié selon les cultivars de bananes et de bananes plantain rencontrés et également en fonction de l’agro-écologie des régions de production. Les pathogènes isolés et identifiés ont montré que les phénotypes diffèrent dans la quasi-totalité des sites visités. Les caractéristiques phénotypiques de l’aspect noir du revers des boîtes de Pétri et non jaune des cultures ont permis de suspecter Mycosphaerella fijiensis. Conclusion et application des résultats : Cette étude a permis de faire ressortir dans toutes les zones agro-écologiques, le caractère épidémique de la cercosporiose noire dans les conditions naturelles d’infestation de production. La cercosporiose jaune est présente uniquement dans les zones agro-écologiques II, III et V. Les résultats de cette étude ont montré une variabilité entre les isolats de Mycosphaerella spp. et aideront à envisager une méthode de lutte alternative à la lutte chimique contre la maladie des raies noires.
Acute toxicity and antimalarial studies of extract of Allophylus spicatus in animals
(Toxicol Res, 2021-01-09) Adebayo, Abiodun H.; Yakubu, Omolara F.; Ishola, Temitope A
Medicinal plants produce a variety of chemical substances with varied physiological effects. They are a huge reservoir of various chemical substances with potential therapeutic properties. Allophylus spicatus is a shrub that belong to the Sapindaceae family. In this study, male albino wistar rats (18) were used for acute toxicity test. Animals were divided into six groups of three rats each. Group A served as the control group while the other groups were dosed orally with 200, 500, 1000, 2000 and 5000 mg/kg body weight of extract and were observed for 14 days. Swiss albino mice (42) were used for the antimalarial study; five groups of six infected mice per group (Groups C–G) were respectively dosed orally with 25 mg chloroquine/kg bw, 200 mg of extract/kg bw, 400 mg/kg bw of extract, 25 mg chl./kg bw+200 mg/kg bw of extract and 25 mg chl./kg bw+400 mg/kg bw extract with three groups serving as the control (Groups A–C) for three days. Acute toxicity test and histology analysis on the liver tissue confrmed the safety of the extract at concentrations less than 1000 mg/kg b/w. Antimalarial studies showed the highest activity in the group administered with 400 mg/kg+25 mg chl./kg b/w. In conclusion, A. spicatus was non-toxic at doses less than 1000 mg/kg and significantly reduced parasitemia count in P. berghei infected mice, thus validating its folkloric usage.
Acute, sub-acute, sub-chronic and chronic toxicity studies of four important Nigerian ethnomedicinal plants in rats
(Springer Nature, 2021-01-02) Abdullah M. Tauheed, Abdullah M.; Mamman, Mohammed; Ahmed, Abubakar
Background: Azadirachta indica, Khaya senegalensis, Anogeissus leiocarpus and Tamarindus indica are important ethnomedicinal plants used for health mitigation since the history of mankind. They are used discretionarily in folkloric medicine on the premise that they are natural products devoid of synthetic preservatives. However, nature endows plants with metabolites for warding off potential attacks from animals and the environment. Some of these metabolites are responsible for toxicity of some plants. Furthermore, drug-induced liver injuries and nephrotoxicity are the leading causes of pharmaceutical attrition of promising drug candidates in clinical trials. Thus, we aimed to evaluate the safety of four ethnomedicinal plants in short-, medium- and long-term usage. Methods: Rats dosed once with 5000 mg/kg extracts of each of these plants served as acute study (AS) while rats dosed daily with 2000 mg/kg for 2, 12 and 14 weeks served as sub-acute (SAS), sub-chronic (SCS) and chronic (CS) studies, respectively. Rats administered distilled water served as the negative control (NC). Results: A. leiocarpus and T. indica significantly reduced percentage weight gain in the SCS compared to the NC. A.leiocarpus significantly (P< 0.05) increased transaminases and alkaline phosphatase in the AS only; and total protein (TP) in the AS, SAS, SCS and CS compared to the NC. K. senegalensis significantly (P< 0.05) increased alanine aminotransferase but significantly (P< 0.05) decreased TP in the AS only compared to the NC. However, A. indica and T. indica significantly (P< 0.05) increased globulin and aspartate transaminase in the CS only. Whereas A. leiocarpus and K. senegalensis significantly (P< 0.05) increased urea and creatinine in the AS than SAS, SCS and CS; Na+ and K+ were significantly higher in the SCS and CS studies compared to the NC. The histological lesions seen ranged from cellular degeneration, congestion, fibrosis to necrosis. Conclusion: Thus, nonlethal, reversible toxic insults occur in short-term usage (AS); while, insidious lethal toxic effects occur in medium-term (SAS) and long-term usage (SCS and CS). The ability of these plant to maintain adequate hematological parameters, bodyweight and absence of mortality may explain free usage of preparations made from these plants in folkloric medicine
Adaptation Responses to Early Drought Stress ofWest Africa Sorghum Varieties
(MDPI, 2021-02) Gano, Boubacar; Dembele, Joseph Sékou B.; Tovignan, Thierry Klanvi
Sorghum is the fifth most important cereal crop world-wide and feeds millions of people in the Sahel. However, it often faces early-stage water deficit due to false onsets of rainy seasons resulting in production decrease. Therefore, developing early drought tolerant material becomes a necessity but requires a good knowledge of adaptation mechanisms, which remains to be elucidated. The present study aimed at assessing the effects of early drought stress on ten elite sorghum varieties tested over two years (2018–2019) at the National Agronomic Research Centre (CNRA) of Bambey (Senegal, West Africa). Two different water regimes (well-watered and drought stress) were applied during the dry season. Water stress was applied by withholding irrigation 25 days after sowing for one month, followed by optimal irrigation until maturity. Soil moisture measurements were performed and allowed to follow the level of stress (down to a fraction of transpirable soil water (FTSW) of 0.30 at the end of stress). An agro-physio-morphological monitoring was carried out during the experiment. Results showed highly significant effects of early drought stress in sorghum plants growth by decreasing leaf appearance, biomass, height but also yield set up. The combined analysis of variance revealed highly significant differences (p 0.01) between varieties in the different environments for most characters. Under water deficit, the variability was less strong on leaf appearance and plant height at the end of stress. The adaptation responses were related to the capacity of varieties to grow up fast and complete their cycle rather, increase the dead leaves weight, reduce photosynthesis rate, stomatal conductance, leaf transpiration and increase the roots length density. However, varieties V1, V2, V8 and V9 showed promising behavior under stress and could be suitable for further application in West Africa for sorghum breeding and farming
Adapting the QUEFTS model to predict attainable yields when training data are characterized by imperfect management
(Elsevier, 2021) Ravensbergen, Arie Pieter Paulus; Chamberlin, Jordan; Craufurd, Peter
Understanding yield responses to nutrient application is a key input for extension advice and strategic agricultural investments in developing countries. A commonly used model for yield responses to nutrient inputs in tropical smallholder farming systems is QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils). While QUEFTS has a strong conceptual foundation, a key assumption is that nutrients are the only limiting factors. One implication of this is the required assumption of ‘perfect management’. This may be problematic in the application of QUEFTS in smallholder farming systems with a wide variety of yield limiting factors. In a previous study, QUEFTS was calibrated using farm trials in two major maize production zones in Nigeria. To reduce observed variability in correlations between estimated soil nutrient (N, P, K) supply and soil parameters (e.g. soil organic carbon, soil pH; step 1 of QUEFTS) a Mahalanobis distance method was used to remove data points not adhering to expected correlations. In this study, we assessed an alternative approach: can the QUEFTS model be adapted to fit smallholder farming systems and associated variation in management? Using 676 observations from the same nutrient omission trials in two major maize production zones in Nigeria, we compare a standard linear regression approach with a quantile regression approach to calibrate QUEFTS. We find that under the standard linear regression approach, there is a poor relation between predicted and observed yields. Using quantile regression, however, QUEFTS performed better at predicting attainable yields – defined as the 90th percentile of observed yields – under a wide variety of production conditions. Our results indicate that using quantile regression as a way to predict attainable yields, is a useful alternative implementation of QUEFTS in smallholder farming systems with high variability in management and other characteristics.
Adapting the QUEFTS model to predict attainable yields when training data are characterized by imperfect management
(Field Crops Research, 2021-03-31) Ravensbergen, Arie Pieter Paulus; Chamberlin, Jordan
Understanding yield responses to nutrient application is a key input for extension advice and strategic agricultural investments in developing countries. A commonly used model for yield responses to nutrient inputs in tropical smallholder farming systems is QUEFTS (QUantitative Evaluation of the Fertility of Tropical Soils). While QUEFTS has a strong conceptual foundation, a key assumption is that nutrients are the only limiting factors. One implication of this is the required assumption of ‘perfect management’. This may be problematic in the application of QUEFTS in smallholder farming systems with a wide variety of yield limiting factors. In a previous study, QUEFTS was calibrated using farm trials in two major maize production zones in Nigeria. To reduce observed variability in correlations between estimated soil nutrient (N, P, K) supply and soil parameters (e.g. soil organic carbon, soil pH; step 1 of QUEFTS) a Mahalanobis distance method was used to remove data points not adhering to expected correlations. In this study, we assessed an alternative approach: can the QUEFTS model be adapted to fit smallholder farming systems and associated variation in management? Using 676 observations from the same nutrient omission trials in two major maize production zones in Nigeria, we compare a standard linear regression approach with a quantile regression approach to calibrate QUEFTS. We find that under the standard linear regression approach, there is a poor relation between predicted and observed yields. Using quantile regression, however, QUEFTS performed better at predicting attainable yields – defined as the 90th percentile of observed yields – under a wide variety of production conditions. Our results indicate that using quantile regression as a way to predict attainable yields, is a useful alternative implementation of QUEFTS in smallholder farming systems with high variability in management and other characteristics.
An Adaptive Genetic Algorithm with Recursive Feature Elimination Approach for Predicting Malaria Vector Gene Expression Data Classification using Support Vector Machine Kernels
(Walailak J Sci & Tech, 2021-07-27) Arowolo, Micheal Olaolu; Adebiyi, Marion Olubunmi; Nnodim, Chiebuka Timothy
Adherence to antiretroviral therapy among HIV patients visiting HIV counselling centres in selected hospitals, Benin City, Edo State
(International Journal of Nursing, Midwife and Health Related Cases, 2020-05) EHWARIEME, Timothy .A; UNIGWE, Joy K; IDHIGU, Kingsley U
The introduction of antiretroviral drugs over the past two decades has helped greatly towards controlling HIV/AIDS infection outcome. However its effectiveness depends largely on adherence to the drug. This study was undertaken to assess adherence to antiretroviral drugs among HIV patients visiting HIV counselling centres in selected hospitals, Benin City, Edo state. The study was carried among 220 HIV patients visiting three selected counselling centre in Benin City using convenient sampling technique and a self-structured questionnaire. Data collected were analysed using descriptive statistics and inferential statistics such as Chi square, multivariate logistic regression and ANOVA were used to test hypothesis at 5% level of significance. Result shows 78(35.9%) have poor knowledge, 60(27.6%)) have moderate, while the remaining 79(36.40) have good knowledge. majority 171(77.7%) have good adherence level. factors are food (2.66±1.03), Unavailability drugs (2.76±0.98), drug toxic effect (2.61±0.88), Stigmatization (2.60±0.96) were found to affect adherence. There was no significant relationship (p>0.05) between adherence of sociodemographic characteristics. However significant difference (p<0.05) was found in the level of knowledge among HIV patient. Multivariate logistic regression showed that respondents that are 18 – 20 years are ten times (O.R = 10.39; C.I = 1.01-107.10) more likely not to adhere than those above 50years. Also respondents with tertiary education are 19% (O.R. 0.81; C.I. = 0.15 – 4.20) less likely not to adhere than those with no education and Christians are 50% (O.R. = 0.50; C.I. = 0.12-2.05) less likely not to adhere than those with traditions/other religion. Conclusion more awareness campaigns and other interventions are needed to improve and sustain the present level of adherence.
Adsorption of Heavy Metals Contaminants in Used Lubricating Oil Using Palm Kernel and Coconut Shells Activated Carbons
(2020-03-10) Opoku, Boadu Kwasi; Friday, Joel Ogbonna; Kofi, Essumang David
Abstract: This research work investigated the adsorption of some heavy metals contaminants in used lubricating oil using chemically activated carbon adsorbents produced from palm kernel and coconut shells. The adsorption mechanism was able to remove some heavy metals such as zinc, chromium, cadmium and magnesium contaminants from the used lubricating oil to appreciable levels. For instance, zinc from initial concentrations of 16.475±0.950 ppm before to 10.375±0.171 ppm after filtration processes for used lubricating oil sample A. Also, for coconut shell from an initial concentration of 14.575±0.272 ppm to 5.450±0.3000 ppm after filtration processes. It was observed that the coconut shell activated carbons was effective in the removal of lead metals while palm kernel cannot. However, the activated carbons produced from palm kernel and coconut shells are not suitable for the removal of both copper and iron metals. For example, after the filtration process with the palm kernel shell activated carbon, the mean concentration of copper metal increases for virgin (C) 0.001± 0.000 to 0.075±0.013 ppm and used lubricating oil samples (A&B) from 0.150±0.008 to 0.400±0.018 ppm and from 0.220±0.096 to 0.230±0.008 ppm respectively. Also, in the case of the coconut shell activated carbon, the mean concentration of copper in virgin lubricating oil remains the same 0.001±0.000 whereas for used lubricating oils samples (i.e. A&B) it increases from 0.150±0.008 to 0.780±0.014 and from 0.220±0.096 to 0.790±0.026 respectively. Also, the equilibrium adsorption data were analysed using the Langmuir isotherm model. The fit of this isotherm model to the equilibrium adsorption data was determined, using the linear coefficient of correlation (R2). The following R2 values were obtained; Copper (0.8185), Cadmium (0.8347), Lead (0.9349), Chromium (0.9378), Iron (0.9927), Zinc (0.9953), and Magnesium (0.9997) respectively. From the results obtained and statistics point of view, it can be concluded that the Langmuir model shows a better fit due to the high coefficient of correlation (R2 ≈ 1). The recovered oil could be also re-used.
Adsorption of Heavy Metals Contaminants in Used Lubricating Oil Using Palm Kernel and Coconut Shells Activated Carbons
(Science Publishing Group, 2020-03-10) Boadu, Kwasi Opoku; Joel, Ogbonna Friday; Essumang, David Kofi
This research work investigated the adsorption of some heavy metals contaminants in used lubricating oil using chemically activated carbon adsorbents produced from palm kernel and coconut shells. The adsorption mechanism was able to remove some heavy metals such as zinc, chromium, cadmium and magnesium contaminants from the used lubricating oil to appreciable levels. For instance, zinc from initial concentrations of 16.475±0.950 ppm before to 10.375±0.171 ppm after filtration processes for used lubricating oil sample A. Also, for coconut shell from an initial concentration of 14.575±0.272 ppm to 5.450±0.3000 ppm after filtration processes. It was observed that the coconut shell activated carbons was effective in the removal of lead metals while palm kernel cannot. However, the activated carbons produced from palm kernel and coconut shells are not suitable for the removal of both copper and iron metals. For example, after the filtration process with the palm kernel shell activated carbon, the mean concentration of copper metal increases for virgin (C) 0.001± 0.000 to 0.075±0.013 ppm and used lubricating oil samples (A&B) from 0.150±0.008 to 0.400±0.018 ppm and from 0.220±0.096 to 0.230±0.008 ppm respectively. Also, in the case of the coconut shell activated carbon, the mean concentration of copper in virgin lubricating oil remains the same 0.001±0.000 whereas for used lubricating oils samples (i.e. A&B) it increases from 0.150±0.008 to 0.780±0.014 and from 0.220±0.096 to 0.790±0.026 respectively. Also, the equilibrium adsorption data were analyzed using the Langmuir isotherm model. The fit of this isotherm model to the equilibrium adsorption data was determined, using the linear coefficient of correlation (R 2 ). The following R2 values were obtained; Copper (0.8185), Cadmium (0.8347), Lead (0.9349), Chromium (0.9378), Iron (0.9927), Zinc (0.9953), and Magnesium (0.9997) respectively. From the results obtained and statistics point of view, it can be concluded that the Langmuir model shows a better fit due to the high coefficient of correlation(R 2≈ 1). The recovered oil could be also re-used
Advanced Burkitt Lymphoma in Sub-Saharan Africa Pediatric Units
(Research Gate, 2019-11) Bouda, Gabrielle C.; Traore, Fousseyni; Couitchere, Line; Raquin, Marie-Anne; Guedenon, Koffi M.; Pondy, Angele; Moreira, Claude; Rakotomahefa, Mbola; Harif, Mhamed; Patte, Catherine
Purpose To evaluate the results of an intensive polychemotherapy regimen for Burkitt lymphoma (BL) in sub-Saharan African pediatric centers. Patients and Methods Children with advanced-stage BL (stages II bulky, III, and IV) treated with the GFAOP–Lymphomes Malins B (GFALMB) 2009 protocol in 7 centers between April 2009 and September 2015 were prospectively registered. Treatment regimen contained a prephase with cyclophosphamide followed by 2 induction courses (cyclophosphamide, vincristine, prednisone, high-dose methotrexate [HDMTX]), 2 consolidation courses (cytarabine, HDMTX), and a maintenance phase only for stage IV. HDMTX was given at the dose of 3 g/m2. Results Four hundred patients were analyzed: 7% had stage II bulky, 76% stage III, and 17% stage IV disease. Median age was 7.3 years, and sex ratio was 1.9:1 (male:female). A total of 221 patients received the whole protocol treatment and 195 achieved complete remission (CR), 11 of them after a second-line treatment. Treatment abandonment rate was 22%. One hundred twenty-five patients died, of whom 49 deaths were related to treatment toxicity. A total of 275 patients are alive, including 25 despite treatment abandonment, but only 110 are known to be in CR with a follow-up . 1 year, indicating a high rate of loss to follow-up. Twelve-month overall survival (OS) was 60% (95% CI, 54% to 66%) and 63%, 60%, and 31%, respectively, for stage II bulky, III, and IV. Patients with stage III disease who started second induction course within 34 days had OS of 76%, versus 57% (P = .0062) beyond 34 days. Coclusion The GFA-LMB2009 protocol improved patients’ survival. Early dose intensity of treatment is a strong prognostic factor. Improving supportive care and decreasing loss to follow-up are crucial.
Advances in biotechnological applications of waste cooking oil
(Case Studies in Chemical and Environmental Engineering, 2021-10-31) Awogbemi, Omojola; Von Kallon, Daramy Vandi; Aigbodion, Victor Sunday
Waste cooking oil (WCO) is generated when edible vegetable oil is used for frying food items. Inappropriate disposal of WCO exacerbates environmental pollution, block drains and contaminates terrestrial and aquatic habitats while its consumption deleteriously impacts human and animal health. In this review, the current efforts into the biotechnological conversion and applications of WCO as feedstock for biofuel, bisabolene, biolubricants, liquid detergents, dishwashing soap and aromatherapy candle, plasticizer, polyurethane foam, surfactants, asphalt rejuvenator are discussed. Aspects related to the global scenario of WCO generation, their physico-chemical properties and avenues of their utilization are also presented. These applications ensure appropriate utilization of WCO as valuable household commodities and industrial products. More investigations are needed for the deployment of WCO for the production of valuable products and to promote circular economy.
Africa needs to prioritize One Health approaches that focus on the environment, animal health and human health
(Nature Medicine, 2021-05-20) Namisango, Eve; Ochu, Chinwe; Effa, Emmanuel
Urbanization, armed confict, and deforestation in African countries have increased the risk of zoonotic infections, which requires a One Health approach focused on the environment, animal health and human health.
Allognissode, F.K, Diop, M.A, Ezzinbi, K, Ogouyandjou, C. (2019) Stochastic partial functional integrodifferential equations driven by a sub-fractional Brownian motion, existence and asymptotic behavior, Random Operators and Stochastic Equations. https://doi.org/10.1515/rose-2019-2009
(De Gruyter, 2019-05-10) Allognissode, Fulbert Kuessi; Diop, Mamadou Abdoul; Ezzinbi, Khalil; Ogouyandjou, Carlos
This paper deals with the existence and uniqueness of mild solutions to stochastic partial functional integro-differential equations driven by a sub-fractional Brownian motion S[H/Q] (t), with Hurst parameter H∈(1\2,1). By the theory of resolvent operator developed by R. Grimmer (1982) to establish the existence of mild solutions, we give sufficient conditions ensuring the existence, uniqueness and the asymptotic behavior of the mild solutions. An example is provided to illustrate the theory.

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