14 research outputs found

    Urbanization and climate change: the role of road transport in carbon dioxide emission in Kano Metropolis, Nigeria

    Get PDF
    No AbstractKeywords: CO2 abatement, automobile density, climate change, global warming, greenhouse gase

    Performance of pearl millet variety LCIC-MV1 in a pearl millet-cowpea-based system in Nigeria

    Get PDF
    The performance of a new pearl millet (Pennisetum glaucum) cultivar LCIC-MVI in a traditional and improved intercropping system with cowpea was determined in a field experiment in Nigeria, in 1999. In traditional intercropping, pearl millet and cowpea were sown in 1 : 1 ratio, while in the improved system, 2 rows of pearl millet cv. LCIC-MV1 were cropped with 4 rows of cowpea cv. IT 90K 277-2. The improved system produced higher pearl millet stover and grain yields than the traditional system

    Influence of egg shell as heterogeneous catalyst in the production of biodiesel via transesterification of Jatropha oil

    Get PDF
    The increase in energy demand together with the negative global environmental impacts of using fossil fuel for energy generations brings a question on dependability on it for sustainable economic growth. The way out is the use of renewable sources of energy such as biodiesel which has significant advantages over its counterpart (fossil fuel). Biodiesel can be produced through various methods such as transesterification, micro emulsion and pyrolysis. The influence of egg shell as heterogeneous catalysts in the production of biodiesel via transesterification of Jatropha oil was investigated. The physical and chemical properties of the catalyst were studied using scanning electron microscopy (SEM) and Xray fluoroscopy (XRF) characterizations. The crude Jatropha oil was transesterified and 0.1 wt%, 0.2 wt%, 0.3wt%, 0.5wt% and 0.5wt% of egg shell were used as heterogeneous catalyst during transesterification process. Fourier Transform Infrared (FTIR) was used to determine the functional group of the samples. SEM and FTIR characterizations indicate the presence of dispersed particles on the catalyst and ester (biodiesel) on the samples respectively. The maximum percentage of biodiesel yield is 94.3% at the application of 0.2wt% egg shell as catalyst using 1:6 oil to methanol ratio in 1hr at 60-65℃. This indicated that the egg shell has high potential to be used as catalyst in the production of biodiesel via transesterification of Jatropha oil

    Effects of zinc oxide nanoparticles on viscosity of transesterified neem oil

    Get PDF
    Efforts have been made worldwide to find alternative fluids for industrial applications. Vegetable oil appears to be a perfect alternative, but using most of the vegetable oil as a feedstock made its use for industrial purposes challenging. The recent trend is to develop coolants/lubricants from non-edible seed oil. This work investigates the effects of zinc oxide nanoparticles on viscosity of transesterified neem oil. The crude neem oil was purified, transesterified and nanoparticles were dispersed in the transesterified oil at concentrations ranging from 0.0% to 1.0% at 0.2% intervals. Fourier Transform Infrared (FTIR) spectra were used to examine the structures of the samples and Scanning Electron Microscopy (SEM) analyses were used to examine the surface morphology of the samples. Viscosity were examined. Among other things, it was found that a small amount of ZnO (0.6%) nanoparticles in the oil could improve the viscosity of the fluid. The nanoliquid with a ZnO concentration of 0.6% appears to have optimal properties

    MasakhaNER 2.0: Africa-centric Transfer Learning for Named Entity Recognition

    Get PDF
    African languages are spoken by over a billion people, but are underrepresented in NLP research and development. The challenges impeding progress include the limited availability of annotated datasets, as well as a lack of understanding of the settings where current methods are effective. In this paper, we make progress towards solutions for these challenges, focusing on the task of named entity recognition (NER). We create the largest human-annotated NER dataset for 20 African languages, and we study the behavior of state-of-the-art cross-lingual transfer methods in an Africa-centric setting, demonstrating that the choice of source language significantly affects performance. We show that choosing the best transfer language improves zero-shot F1 scores by an average of 14 points across 20 languages compared to using English. Our results highlight the need for benchmark datasets and models that cover typologically-diverse African languages

    MasakhaPOS: Part-of-Speech Tagging for Typologically Diverse African languages

    Get PDF
    In this paper, we present AfricaPOS, the largest part-of-speech (POS) dataset for 20 typologically diverse African languages. We discuss the challenges in annotating POS for these languages using the universal dependencies (UD) guidelines. We conducted extensive POS baseline experiments using both conditional random field and several multilingual pre-trained language models. We applied various cross-lingual transfer models trained with data available in the UD. Evaluating on the AfricaPOS dataset, we show that choosing the best transfer language(s) in both single-source and multi-source setups greatly improves the POS tagging performance of the target languages, in particular when combined with parameter-fine-tuning methods. Crucially, transferring knowledge from a language that matches the language family and morphosyntactic properties seems to be more effective for POS tagging in unseen languages

    Effects of antibiotic resistance, drug target attainment, bacterial pathogenicity and virulence, and antibiotic access and affordability on outcomes in neonatal sepsis: an international microbiology and drug evaluation prospective substudy (BARNARDS)

    Get PDF
    Background Sepsis is a major contributor to neonatal mortality, particularly in low-income and middle-income countries (LMICs). WHO advocates ampicillin–gentamicin as first-line therapy for the management of neonatal sepsis. In the BARNARDS observational cohort study of neonatal sepsis and antimicrobial resistance in LMICs, common sepsis pathogens were characterised via whole genome sequencing (WGS) and antimicrobial resistance profiles. In this substudy of BARNARDS, we aimed to assess the use and efficacy of empirical antibiotic therapies commonly used in LMICs for neonatal sepsis. Methods In BARNARDS, consenting mother–neonates aged 0–60 days dyads were enrolled on delivery or neonatal presentation with suspected sepsis at 12 BARNARDS clinical sites in Bangladesh, Ethiopia, India, Pakistan, Nigeria, Rwanda, and South Africa. Stillborn babies were excluded from the study. Blood samples were collected from neonates presenting with clinical signs of sepsis, and WGS and minimum inhibitory concentrations for antibiotic treatment were determined for bacterial isolates from culture-confirmed sepsis. Neonatal outcome data were collected following enrolment until 60 days of life. Antibiotic usage and neonatal outcome data were assessed. Survival analyses were adjusted to take into account potential clinical confounding variables related to the birth and pathogen. Additionally, resistance profiles, pharmacokinetic–pharmacodynamic probability of target attainment, and frequency of resistance (ie, resistance defined by in-vitro growth of isolates when challenged by antibiotics) were assessed. Questionnaires on health structures and antibiotic costs evaluated accessibility and affordability. Findings Between Nov 12, 2015, and Feb 1, 2018, 36 285 neonates were enrolled into the main BARNARDS study, of whom 9874 had clinically diagnosed sepsis and 5749 had available antibiotic data. The four most commonly prescribed antibiotic combinations given to 4451 neonates (77·42%) of 5749 were ampicillin–gentamicin, ceftazidime–amikacin, piperacillin–tazobactam–amikacin, and amoxicillin clavulanate–amikacin. This dataset assessed 476 prescriptions for 442 neonates treated with one of these antibiotic combinations with WGS data (all BARNARDS countries were represented in this subset except India). Multiple pathogens were isolated, totalling 457 isolates. Reported mortality was lower for neonates treated with ceftazidime–amikacin than for neonates treated with ampicillin–gentamicin (hazard ratio [adjusted for clinical variables considered potential confounders to outcomes] 0·32, 95% CI 0·14–0·72; p=0·0060). Of 390 Gram-negative isolates, 379 (97·2%) were resistant to ampicillin and 274 (70·3%) were resistant to gentamicin. Susceptibility of Gram-negative isolates to at least one antibiotic in a treatment combination was noted in 111 (28·5%) to ampicillin–gentamicin; 286 (73·3%) to amoxicillin clavulanate–amikacin; 301 (77·2%) to ceftazidime–amikacin; and 312 (80·0%) to piperacillin–tazobactam–amikacin. A probability of target attainment of 80% or more was noted in 26 neonates (33·7% [SD 0·59]) of 78 with ampicillin–gentamicin; 15 (68·0% [3·84]) of 27 with amoxicillin clavulanate–amikacin; 93 (92·7% [0·24]) of 109 with ceftazidime–amikacin; and 70 (85·3% [0·47]) of 76 with piperacillin–tazobactam–amikacin. However, antibiotic and country effects could not be distinguished. Frequency of resistance was recorded most frequently with fosfomycin (in 78 isolates [68·4%] of 114), followed by colistin (55 isolates [57·3%] of 96), and gentamicin (62 isolates [53·0%] of 117). Sites in six of the seven countries (excluding South Africa) stated that the cost of antibiotics would influence treatment of neonatal sepsis

    Construction of a simple laptop battery charger that can use 19V DC/3A to charge a battery

    No full text
    In this article, a construction of a laptop battery charger was carried out. The laptop battery charger consists of a transformer which steps down the 220VAC to 12VAC, the rectifier which converts the AC input to pulsated DC voltages and a capacitor which filtered the pulsated DC voltage, while the regulator regulates the voltage that is used to charge the 19VDC laptop rechargeable battery. However, the design and construction of 12VDC laptop battery charger was carried to charge laptop battery. Automatic charging was not included due to limited resources. The charger was tested and found to function properly. This charger is very simple, affordable and can be used anywhere

    Toxicity study of four partially purified leaf extract of Vitex simplicifolia on liver function in wistar rats

    No full text
    This study evaluated the liver toxicological indices, following 21 days administration of fractionated leaf extracts of Vitex simplicifolia in Wistar rats. Acute toxicity studies with very high concentrations of the four fractionated extracts were carried out followed by sub chronic toxicities studies involving administration of 250mg/kg, 500mg/kg and 1000mg/kg body weight of the four fractionated leaf extracts to the experimental animals for 21 days. Aqueous, methanolic and ethyl acetate fractions significantly increase Alanine transaminase ALP (P < 0.05) and significantly decrease (P < 0.05) Aspartate transaminase (AST). However, the n- hexane fraction showed significant increase in ALP, AST and unconjugated bilirubin. The histopathological studies of the liver showed mild to moderate sinusoidal lymphocytosis with prominent kupfer cells and focal portal inflammation in the test groups. These observations shows that care should be taken when using Vitex simplicifolia as a phytoremedy against any ailments as sub chronic administration at high concentrations of the extract may induce injury to the liver.Keywords: Vitex simplicifolia, Unconjugated billirubin, Alanine aminotransferase, Aspartate transaminase,  Aspartate  transaminas
    corecore