Design Considerations of a Flexible Biogas Digester System for Use in Rural Communities of Developing Countries

Several challenges are associated with the development, adoption and deployment of biogas digesters in developing countries. Amongst these challenges is a comprehensive and systematic procedure for the design of digesters suitable for rural communities. This paper proposes the Flexible Biogas Digester System (FBDS) as a viable option for rural communities in developing countries and provides a detailed step-by-step procedure for its design. The biogas production process is a function of the digester operating factors which may be grouped into physical, process and performance parameters. The physical design parameters include the digester volume, the volume of the biogas storage tank, and the volume of the installation pit. The process parameters include total solid content of the slurry (TS), organic loading rate (OLR), digester operating temperatures, pH of the slurry inside the digester. The performance parameters include biogas production rate, biogas productivity and biogas quality. The Net Present Value and the Levelised Cost of Energy are presented for simple economic evaluation of the FBDS.

Global Climate Change Impacts on Human Health in Sub-Sahara Africa

Health and climate have been linked since antiquity.The impact of climate change on human health has received increasing recognition since it was first mentioned in the IRCC(Intergovernmental Report on Climate Change).Climate change is widely considered to be a major driver of inter-annual variability of malaria incidence in Africa.Several researches have suggested that climate can affect infectious disease patterns because disease agents

Veterinary Laboratory Diagnosis: A Missed Opportunity in the Continuum of Care for Veterinarians in Selected Countries in Sub-Sahara Africa

In Africa, sustainable livestock production must address food security, as well as animal disease concerns simultaneously in addition to social aspects. Livestock disease challenges seem to be increasing with one of them being lack of good animal diagnostics services with notable emerging zoonotic diseases which if not correctly diagnosed in animals pose risks to humans. The major livestock hubs in sub-Sahara Africa (SSA) include Uganda, Ethiopia, Tanzania and Nigeria and utilization of diagnostic services by veterinarians in these countries could inform further action by different stakeholders in the SSA region. A cross sectional survey with veterinarians was conducted between January 2022 and February 2022 to determine the number of veterinarians who have submitted samples for veterinary diagnosis, laboratory utilization rates and challenges faced by veterinarians using veterinary labs in sub-Sahara Africa between the period of 2018 and 2022. Methods: This was a cross sectional study, where an online questionnaire was shared with veterinarians through their online social group networks in different countries and data was captured and analyzed. Results: 74% (64/87) of veterinarians reported having submitted a sample to a lab, Government labs were the most utilized at 54%, followed by private labs at 37% and the human health labs recorded 9% utilization rate. The most faced challenge by veterinarians was failing to get samples to the lab because the labs where far (52%) with the least challenge reported being failure to understand the lab results at 3%. Conclusion: Government labs were the most utilized in this period, however notable challenges like failing to get samples to the lab still exist. Veterinary diagnosis is still an underutilized service in sub-Sahara Africa and more measures need to be worked on in terms of sample logistics, capacity building and trainings of both lab personnel and veterinarians in interpretation of results to ensure improved utilization of veterinary diagnostics services.

A Preliminary Feasibility Study on Wind Resource and Assessment of a Novel Low Speed Wind Turbine for Application in Africa

This paper posits that a low-speed wind turbine design is suitable for harnessing wind energy in Africa.Conventional wind turbines consisting of propeller designs are commonly used across the world.A major hurdle to utilizing wind energy in Africa is that conventional commercial wind turbines are designed to operate at wind speeds greater than those prevalent in most of the continent,especially in sub-Sahara Africa(SSA).They are heavy and expensive to purchase,install,and maintain.As a result,only a few countries in Africa have been able to include wind energy in their energy mix.In this paper,the feasibility of a novel low-speed wind turbine based on a Ferris wheel is demonstrated for low wind speed applications in Africa.The performance of Ferris wheel wind turbines(FWT)with 61m(200 ft),73m(240 ft)and 104m(341 ft)diameter rims and an 800kW generator are evaluated for selected African cities.The research also compares the Weibull wind distribution of the African cities of interest.A comparison between the FWT and the conventional commercial wind turbines in terms of efficiency,rated wind speed,cost,performance,and power to weight is included.Results show that the FWT has the potential for economic power generation at rated wind speeds of 6.74m/s,which are lower than the average of 12 m/s for conventional wind turbines and have lower power to weight ratios of 5.2 kW/tonne as compared to 6.0-9.2 kW/tonne for conventional wind turbines.

Modelling Electricity Generation and Capacity with CO₂Emissions for Sub Saharan Africa

In this investigation the electricity generation and the electricity capacity of energy mix for sub Saharan Africa from 2020 to 2040 including CO2 emission from (coal, oil, gas) (Total Final Consumption, transport) and power generation were analyzed. These energy sources include conventional and renewable energy sources such as coal, oil, gas, hydro, nuclear, bioenergy, solar PV, and other renewables. We developed a linear regression equation based on the least-square method of estimation to forecast the value of energy and CO2 emission. We fit a linear trend to the energy time series including CO2 emission to show how simple linear regression analysis can be used to forecast future value. The predicted results from 2020 to 2040 show that the electricity capacity and the electricity generation from gas, hydro, solar PV and other renewables will dominate compared to nuclear and bioenergy. Some forms of energies contributions such as nuclear and bioenergy will remain insignificant. The gas will continue to emit a lot carbon dioxide compared to the emission from oil and coal. The emission of CO2 from total final consumption (TFC) of oil will be high compared to its emission from power generation (PG) and transport. The least squares estimated regression equation adequately describes the relationship between Energy or CO2 emission and time period with a high R-squared. This approach of modeling in a linear regression, the energy and CO2 emission simplifies significantly the analysis to help policy makers underlying reasons for the trends to develop appropriate strategies for the future, may be useful to assess the sustained economic development and transformation that require a definition of electricity access in those countries.

Scaling up impact of malaria control programmes: a tale of events in Sub-Saharan Africa and People’s Republic of China

This review aims at providing synthetic information with scientific evidence on the trends in the malaria events from 1960 to 2011,with the hope that it will help policy makers to take informed decisions on public health issues and intervention designs on malaria control towards elimination in both Sub-Sahara Africa and in the People’s Republic of China by highlighting the achievements,progress and challenges in research on moving malaria from epidemic status towards elimination.Our findings showed that since 1960,malaria control programmes in most countries have been disjointed and not harmonized.Interestingly,during the last decade,the causal factors of the unprecedented and substantial decline in malaria morbidity and mortality rates in most vulnerable groups in these endemic areas are multifaceted,including not only the spread of malaria and its related effects but also political and financial willingness,commitment and funding by governments and international donors.The benefits of scaling up the impact of malaria coverage interventions,improvement of health system approaches and sustained commitment of stakeholders are highlighted,although considerable efforts are still necessary in Sub-Sahara Africa.Furthermore,novel integrated control strategies aiming at moving malaria from epidemic status to control towards elimination,require solid research priorities both for sustainability of the most efficient existing tools and intervention coverage,and in gaining more insights in the understanding of the epidemiology,pathogenesis,vector dynamics,and socioeconomic aspects of the disease.In conclusion,political commitment and financial investment of stakeholders in sustaining the scaling up impact of malaria control interventions,networking between African and Chinese scientists,and their Western partners are urgently needed in upholding the recent gains,and in translating lessons learnt from the Chinese malaria control achievements and successes into practical interventions in malaria endemic countries in Africa and elsewhere.

非洲沼气技术发展和潜力

本研究主要着眼于沼气技术的潜在市场、投资和发展瓶颈,简要回顾了非洲沼气技术发展的现状。非洲生物质资源储量丰富,具有进行厌氧消化的巨大潜力,可降低对林木燃料和化石燃料过度依赖并减少温室气体的排放。尽管非洲有着丰富的生物质资源,具有厌氧消化的潜力,但是目前只建设了少量的沼气池。虽然沼气池推广数量在2011年翻了一番,但是这和潜在目标相比还相差甚远。本研究特将发展潜力和问题进行分析讨论。

Irrigated agriculture for food self-sufficiency in the sub-Saharan African region

Increasing agricultural productivity in Africa will have important impacts not only on the agricultural sector but also can be a catalyst for industrialization through agro-processing.Irrigation,therefore,has a crucial role in enhancing food security and reducing hunger in the region.Numerous countries in Africa consider water and irrigation management as a key factor in improving their food security and ensuring access to drinking-water for their populations.Fortunately,there is evidence from a number of places on the continent where the adoption of efficient irrigation systems has led to higher productivity among smallholder farmers.While the appropriate interventions for the diverse agro-ecological zones of sub-Saharan Africa are known,adoption among smallholder farmers still remains a challenge.Digital technology opens the vast untapped potential for farmers,investors,and entrepreneurs to improve the efficiency of food production and consumption in Africa.From precision farming to an efficient food supply chain,technology could bring major economic,social,and environmental benefits.Increasing investment and involvement of the private sector is crucial for the up-scaling of irrigation technologies.Indeed,the sheer optimism across the startup ecosystem is that extreme hunger can be cured in Africa,in this generation,by significantly transforming the industry that employs most of its citizens.This paper draws on lessons from past trends in the irrigation industry and emphasizes on novel directions to ensure that farmers,as well as other stakeholders reap the benefits associated with improved technologies.

Men without Sperms

Introduction: Men without sperm (azoospermic) make up about 15% of all infertile men in reproductive age of fatherhood. Male infertility is a health and social problem in many communities. Subjects and Methods: This retrospective study was carried from 2010 to 2015. Initially, 907 men were included in the study among whom 109 (12.02%), 346 (38.15%) and 452 (49.83%) were azoospermic, oligospermic and normospermic, respectively. This study only investigated the association between age, BMI, semen volume, liquefaction time and pus cells among normospermic and azoospermic men. Standard semen analysis was performed and subjects were categorized by age into Results: The 562 subjects of the study had means (±sd) age of 42.6 (±7.10) years and BMI of 27.0 (4.1) kg/m2 respectively. In all, 109 (19.4%) were azoospermic. Overweight and obese men were, respectively, more than 1? and about 2? times more likely to be azoospermic compared to normal weight men. Azoospermic men were significantly heavier than men with normal sperm count (t = -0.34;P-value = 0.003). Among those with normal weight, liquefaction time was significantly shorter (t = 5.49, P-value = 0.000001) in azoospermic (28.70 min.) than in men with normal sperm count (31.82 min.). Obese azoospermic men were about 4 times as likely to have high pus cells in semen than normal weight azoospermic men (OR = 3.82;95% CI: 0.39, 37.01). Multivariate regression analysis shows a strong but negative coefficient correlation between sperm concentration and BMI (coef. = -0.48, Std Err. = 0.25, P-value = 0.05, 95% CI: -0.96, 0.10). Conclusion: Our findings suggest that high BMI is associated with azoospermia. Azoospermia also did not seem to negatively impact liquefaction time.

Lumbar Spondylolisthesis in Rheumatological Practice in Lome (Togo): Frequency and Semiological Profile

Objectives: To determine the frequency, the clinical and radiological features of lumbar spondylolisthesis in a rheumatological practice in Lomé. Patients and methods: This was a cross-sectional study conducted in the rheumatology department of the Sylvanus Olympio Teaching Hospital in Lomé between January 1997 and December 2019. Medical records of patients with symptomatic spondylolisthesis with radiographic confirmation were reviewed. The Meyerding classification system was used for grading. Results: Of the 350 patients contacted, 118 consented to participate in the study, making a response rate of 33.71%. Of the 118, 104 (88.1%) were females. 109 (92.4%) presented with radicular pain and 9 (7.6%) presented low back pain. The mean age of the patients was 54.24 ± 11.19 years. The average duration of the pain was 4.56 ± 1.32 years. The spondylolisthesis level most involved was the L4 - L5 (92/118), followed by L5 - S1 (23/118). 106 (89.8%) patients had anterolisthesis only, seven (5.9%) combination anterolisthesis and retrolisthesis. The spondylolisthesis was associated with spondylosis in 110 (93.2%) patients. Spondylosis was found at level L4 - L5 in 38.98% patients, followed by L5 - S1 (24.58%), L3 - L4 (18.64%). Grade I slip was found in 108 (91.53%) patients and Grade II slips 10 (8.47%). Isthmic lysis was found in 40 (33.9%) patients and it was located at L4 in 30 (75.0%). Conclusion: Lumbar spondylolisthesis appears to be expected in Lomé patients with nonspecific back pain and mainly affects females.

Low-Cost Automated PV Panel Dust Cleaning System for Rural Communities

Dust accumulation on photovoltaic (PV) panels degrades PV panels’ performance;leading to decreased power output and consequently high cost per generated kilowatt. Research addressing the severity of dust accumulation on PV panels has been ongoing since the 1940s, but proposed solutions have tended to increase the cost of PV systems either from oversizing or from cleaning the system. The objective of this work, therefore, is to design and implement a low-cost affordable automated PV panel dust cleaning system for use in rural communities of Sub-Saharan Africa (SSA);where financial resources are limited and significantly strained in meeting livelihood activities. Complete design and implementation details of a prototype system are provided for easy replication and capitalization on PV systems for sustainable energy needs. The system detects dust based on the innovative use of light-dependent resistors. Testing and observation of the system in operational mode reveal satisfactory performance;measured parameters quantify a power output increase of 33.76% as a result of cleaning dust off the PV panel used in the study.

Geospatial data infrastructure for sustainable development in sub-Saharan countries

People are now using geoinformation for many different purposes and consequently one can confidently say that the need for geospatial data infrastructure(GDI)cannot be overstated in sub-Saharan Africa.Geospatial information(GI)is essential to socioeconomic planning and development of sub-Sahara African countries.This paper therefore examines:GI during the last centuries in sub-Sahara Africa;recent paradigms in GDI in sub-Sahara Africa;the benefit of GDI to the African economy and the future of GDI in sub-Sahara Africa.This study discovered that most countries in sub-Saharan Africa did not have timely access to accurate geospatial data throughout the last centuries.This significantly hindered meaningful social and economic development.Development of GDI nonetheless,will enhance search and retrieval of geospatial data in Africa.This is one of the benefits that can be derived from implementing GDI in sub-Sahara Africa.Therefore,it is necessary to review cadastral survey laws and regulations so as to incorporate the use of recent geospatial equipment.