Single-use bioreactor technologies for early stage development of microalgae cultivation processes

This work describes the engineering characterization and evaluation of two novel, single-use photobioreactor technologies for microalgal cultivation. There is currently considerable interest in microalgae as alternative expression systems for the production of value-added chemicals as well as therapeutic proteins and vaccines. In contrast to mammalian expression systems, however, bioreactor platforms to address early stage development challenges are not well established particularly for phototrophic and mixotrophic cultivation strategies. To support early stage cell line selection and process characterization a single-use, 24-well micro photo-bioreactor (mPBr) was established together with an illuminated and environmentally controlled shaker platform [1]. The same orbital shaker platform was also used for microalgae cultivation up to 10L scale, in single-use bags usually used for mammalian cell cultivation on rocked platforms [2]. Particularly for small and micro-companies this single-use photobioreactor (SUPBr) provides a route for rapid process optimization and materialization of novel products from microalgae. Both bioreactor technologies were characterized in terms of their fluid hydrodynamics, mixing and gas-liquid mass transfer. The influence of these factors as well as light path length and light intensity on growth and pigment formation in Chlorella sorokiniana was also studied. Successful scale translation between the mPBr and the SUPBr was demonstrated illustrating the complementarity of the two approaches to help reduce microalgal bioprocess development timelines

Local Farmers’ Perceptions about Covid-19 Impact on Agriculture: Case of Selected Rural Areas in Ekiti State, Nigeria

The outbreak of the Corona virus that ravaged most parts of the globe including Nigeria had impacted all sectors in all economies. Understanding the perception of rural farmers about Covid-19 pandemic impacts on agricultural activities becomes imperative as it will help local government authorities identify possible vulnerabilities and prioritize interventions. This study therefore seeks 1) to know farmer perceptions of the probable impacts of Covid-19 pandemic on agricultural production process of rural farmers and 2) to examine if this perception varies by the population subgroups of farmers? Using selected rural areas in five local government areas in Ekiti state as case study, primary data obtained through the administered questionnaire were analysed using descriptive statistics and analysis of variance. Results indicated that the two most potential and identified possible vulnerabilities are agricultural output and access to finance, and income with respect to production process and welfare, respectively. ANOVA results indicated that both age and gender are not statistically significant at 5 percent in explaining perceived impact of covid-19 on agricultural output likewise others such as educational attainment, years of farming experience and marital status. Hence, none of the levels in each of the chosen categorical variables is found to be statistically different from the other ones in impacting agricultural production. It is therefore recommended that government policies aimed at stimulating agricultural production should not be gender bias and age driven. Similarly, other factors such as years of farming experience, educational attainment and marital status should be de-emphasized when initiating such policies

Sexuality in Nigerian older adults

Introduction: Oftentimes the older adults are assumed to be asexual as few studies explore into the sexuality of this age group worldwide and even in Nigeria. It is an important aspect of quality of life which is often neglected by people in this age group, attending physicians and the society as a whole. The study was aimed at determining the perception of older adults about sexuality, identify the factors that could militate against sexuality and fill any void in information in this regard. Methods: Descriptive study conducted in one hundred older adults. A semistructured questionnaire was administered to consenting participants between 1st of September 2013 and 31st of March 2014. Results: Mean age of respondents was 66.42± 5.77 years. Seventy-eight percent of the male respondents considered engaging in sexual activity as safe compared to 45.8% of the female respondents. More of the women (33.3%) regarded sexuality in the older adults as a taboo when compared to the men (5.4%). However, the men were more favourably disposed to discussing sexual problems than the women with their spouses (42% vs 20%) and Physicians (23.2% vs 0.0%). Major factors responsible for sexual inactivity were participants' medical ailments (65%), partners' failing health (15%) as well as anxiety about sexual performance (25%) in the men and dyspareunia (25%) in women. Conclusion: There is an urgent need to correct the misconception about sexuality in this age group especially among the women and for the physicians to explore the sexual history of every patient.Pan African Medical Journal 2015; 2

Agro-processing Output and Agricultural Sector Employment: Evidence from South Africa

This paper empirically examined the relationship between agro-processing sub-sector output and agricultural sector employment in South Africa by using time series data from 1975-2015. The study employed ARDL-bounds testing approach to examine the existence long-run equilibrium relationship. The result of the ARDL test confirmed the existence of long-run relationship among the variables examined. The long-run estimate result revealed that the relationship between agro-processing output and agricultural sector employment is negative in the long-run. The study further examined the causality between agro-processing output and agricultural sector employment using TYDL causality test and it observed a unidirectional causal relationship running from agro-processing output to agricultural sector employment. While it is deduced that agro-processing sector output is found to be unable to promote agricultural sector employment, this study recommends stimulation of agricultural export for agricultural sector employment generation in South Africa

Comparative of Ziegler Nichols, Fuzzy Logic and Extremum Seeking Based Proportional Integral Derivative Controller for Quadcopter Unmanned Aerial Vehicle Stability Control

Unmanned aerial vehicle is potentially recognized in autonomous sectors where intelligence gathering, surveillance, reconnaissance missions, power line inspection, aerial video, search and rescue monitoring devices are required. It is essential in modern era control and monitoring especially a rotary unit where quadcopter performed a crucial task. However, the flight behavior of a quadcopter is determined by the synchronous speed of each of the motors as the speed changes with load torque variations. The dynamics model equation of the system, external disturbances and its parameters variation of the motor makes it difficult for the manual tuning techniques employed into the system to perform its stability operation. The purpose of this work is to employ adaptive controllers to enhance the stability performance so as to prevent the risk of human lives and financial implication that may arise from improper monitoring of the system. Therefore, Ziegler Nichols, fuzzy logic and extremum seeking controllers were employed to auto-tuned the parameters of proportional integral derivative (PID) gains controller to optimize and give a satisfactory performance of motor speed control at different operating condition. The altitude, pitch, roll and yaw parameters of the quadcopter are simulated using the x-plane II flight simulator MATLAB tools. The simulation results presented in this work show better performance for extremum seeking-PID in terms of decrease in rise time, settling time and overshoot relative to Zigler-Nichols-PID and Fuzzy-PID controllers

Process safety education framework : lessons from Safety and Chemical Engineering Education (SAChE) faculty workshops

Safety and Chemical Engineering Education (SAChE) program was initiated in 1992 under the auspices of the Center for Chemical Process Safety (CCPS) of the American Institute of Chemical Engineers (AIChE) and engineering schools (http://www.sache.org). Historically, significant progress made over the last two decades include newsletter publication, dedicated website hosting different learning materials, faculty workshops and student safety certificate programmes. This paper is aimed at developing an implementable framework for upskilling engineering graduates in process safety using SAChE workshop as a case study. The developed educational safety framework referred to as Cognitive-Experiential (CogEx) is based on combined cognitive and experiential learning pedagogies adapted to process safety education. For an emerging economy, CogEx implies initiating industry-university collaboration with a focus on process safety education. This further extends to different activities such as faculty workshops and training, curriculum development for process safety modules, industry experts’ participation in teaching and assessments, and the development of educational materials based on current industry practices. In general, the CogEx framework developed provides a structure for skills transferability and programme implementation outside the USA, where SAChE is domiciled. Learning context such as this becomes necessary for enabling robust safety skills and culture exchange. It also proactively mitigates the shortage in process safety expertise for future expansion of the emerging natural gas industry and the established petroleum industry

Household Cooking Energy Situation in Nigeria: Insight from Nigeria Malaria Indicator Survey 2015

The lingering electricity energy crisis in Nigeria which is beyond the control of most households necessitates making decision and choice on alternative energy pathways for households' sustenance and welfare. This study assessed households' energy situation with respect to choice of cooking fuel and cooking energy poverty status in Nigeria. Further investigation was sought to isolate the main factors influencing households' choice of individual fuels as main cooking fuels using data from Nigeria's Malaria Indicator Survey of 2015 with the application of descriptive and multivariate probit analyses. Findings revealed that wood and kerosene fuels remain the major fuels utilized by most households in Nigeria for cooking purposes. Meanwhile, level of education, household size, wealth status and regional factors are significant predictors driving choices of fuels among households, though the impact of these factors differs across the highlighted choices. Based on these findings, mass enlightenment campaign on the safe use of clean energy is recommended while the need for economic diversification by rural households to aid their wealth status is also emphasized. Also, there is need to gear up corporate social responsibilities by the available private establishments in ensuring rural accessibility, availability and affordability of modern and cleaner fuel (such as LPG). Keywords: Cooking Energy Choice, Multivariate Probit Model, Nigeria JEL Classifications: D10, I30, Q40 DOI: https://doi.org/10.32479/ijeep.691

A community survey of the pattern and determinants of household sources of energy for cooking in rural and urban south western, Nigeria

Introduction:The use of solid fuels for cooking is associated with indoor pollution and lung diseases. The objective of the study was to determine the pattern and determinants of household sources of energy for cooking in rural and urban South Western, Nigeria. Methods: We conducted a cross sectional study of households in urban (Ado-Ekiti) and rural (Ido-Ekiti) local council areas from April to July 2010. Female respondents in the households were interviewed by trained interviewers using a semi-structured questionnaire. Results: A total of 670 households participated in the study. Majority of rural dwellers used single source of energy for cooking (55.6%) and urban dwellers used multiple source of energy (57.8%). Solid fuel use (SFU) was higher in rural (29.6%) than in urban areas (21.7%). Kerosene was the most common primary source of energy for cooking in both urban and rural areas (59.0% vs.66.6%) followed by gas (17.8%) and charcoal (6.6%) in the urban areas, and firewood (21.6%) and charcoal (7.1%) in the rural areas. The use of solid fuel was strongly associated with lack of ownership of dwellings and larger household size in urban areas, and lower level of education and lower level of wealth in the rural areas. Kerosene was associated with higher level of husband education and modern housing in urban areas and younger age and indoor cooking in rural areas. Gas was associated with high income and modern housing in the urban areas and high level of wealth in rural areas. Electricity was associated with high level of education, availability of electricity and old age in urban and rural areas respectively. Conclusion: The use of solid fuel is high in rural areas, there is a need to reduce poverty and improve the use of cleaner source of cooking energy particularly in rural areas and improve lung health. Pan African Medical Journal 2012; 12:

FEED PETs: Further Experimentation and Expansion on the Disambiguation of Potentially Euphemistic Terms

Transformers have been shown to work well for the task of English euphemism disambiguation, in which a potentially euphemistic term (PET) is classified as euphemistic or non-euphemistic in a particular context. In this study, we expand on the task in two ways. First, we annotate PETs for vagueness, a linguistic property associated with euphemisms, and find that transformers are generally better at classifying vague PETs, suggesting linguistic differences in the data that impact performance. Second, we present novel euphemism corpora in three different languages: Yoruba, Spanish, and Mandarin Chinese. We perform euphemism disambiguation experiments in each language using multilingual transformer models mBERT and XLM-RoBERTa, establishing preliminary results from which to launch future work

Developing process understanding for continuous manufacturing of Lamivudine (Epivir®) Stable Form I

Why the considerations for Lamivudine? * Increasing numbers of HIV/AIDS infections on yearly basis (2.1 million new cases in 2015, UNAIDS) * Hepatitis B infections (257 million cases globally, WHO) * Currently FDA-approved antiretroviral therapy for the prevention and treatment of both viral infections (FDA). Key research considerations and interests To the best of our knowledge, no publication yet exists on continuous manufacturing of stable Lamivudine form 1. The key research question here is: * Translate current batch crystallisation into a continuous process? * Improve the downstream process-ability by modifying the particle properties? * Develop miniaturise platforms for accelerated process development