Parametric Evaluation of a Parabolic Trough Solar Collector

A parabolic trough collector was studied to determine its performance parameters when stationary and when tracked. The overall heat loss coefficient, heat removal factor, efficiency function, flow factor and its thermal efficiency are the factors of interest. Optimum values obtained for the collector when tracked were as follows: Collector efficiency function, 12m2K/Kw; heat removal factor, 0.59, flow factor, 0.76; overall heat loss, 0.02KW/m2K and thermal efficiency of 56%. Keywords: parabolic trough, performance, parameters

The effects of selected bio-active feed additives on NIle tilapia (Oreochromis niloticus) production and health

Three investigations were conducted to assess the effects of selected bio-active feed additives on tilapia (Oreochromis niloticus) growth performance, feed utilisation, haemato-immunological status, intestinal morphology and microbiology. The first experiment was conducted to evaluate the effects of feeding tilapia semi-practical diets supplemented with exogenous enzymes (phytase, protease or carbohydrase). After six weeks of the dietary supplementation, tilapia fed diets supplemented with exogenous enzymes (phytase and carbohydrase) showed enhanced growth performance and higher microvilli density when compared to the control group. Additionally, the intestinal bacterial community profile of tilapia fed the carbohydrase supplemented diet was significantly altered in contrast to those fed the control diet. In the second experiment, tilapia were fed with practical diets supplemented with exogenous enzymes (phytase, protease or xylanase) for eight weeks. Tilapia fed the xylanase supplemented diet demonstrated significantly higher final body weight (FBW), improved feed conversion ratio (FCR) and better protein efficiency ratio (PER) when compared to the control group. Apparent digestibility coefficients of protein, ash, energy, phosphorus, calcium and sodium were highest in tilapia fed a diet supplemented with phytase. The third experiment was carried out to assess the combined effects of dietary exogenous enzymes (phytase, protease and xylanase) and probiotics (Bacillus subtilis, B. licheniformis and B. pumilus) on tilapia growth performance and health. After seven weeks of feeding, tilapia fed the diet supplemented with both exogenous enzymes and probiotics showed significantly higher FBW, specific growth rate, improved FCR and better PER. The serum lysozyme activity was observed to be significantly higher in tilapia fed the probiotic supplemented diet when compared to the control group. The dietary supplementation with combined exogenous enzymes and probiotics increased intestinal perimeter ratio, microvilli count (density), diameter and subsequently resulted in higher enterocyte absorptive area in tilapia. This study demonstrates that feeding tilapia with dietary exogenous enzymes can enhance growth performance and modulate microbial community profile. In addition, supplementation with both exogenous enzymes and probiotics is capable of improving tilapia growth performance, immune parameters and intestinal morphology.Commonwealth Scholarship Commission in U

Perspectives of health care professionals on artificial insemination of donor semen: appraising their knowledge and perceptions: a single institution study in Nigeria

Background: Artificial inseminations of donor semen (AID) involve use of heterologous donated semen for conception in infertile couple when indicated or in a single woman desirous of pregnancy. Its practice often requires regulation to address possible ethical and legal issues which may arise. In formulating acceptable guidelines/policies, the perspectives of health professionals and the participants should be considered. Therefore, we sought to explore the knowledge and perception of semen donation for artificial insemination among health professionals.Methods: A cross sectional study conducted on consenting health workers in a single health institution using a structured questionnaire to assess their knowledge and perception on artificial insemination of donor semen (AID). Descriptive and analytical statistics were applied to the data collected with a statistically significant value of <0.05.Results: One hundred and twenty-one health professionals completed the questionnaires. The mean age of the respondents was 27.58±5.5years. Sixty of the respondents were males while 61 were females. Eighty-four of the respondents (69.4%) demonstrated good knowledge of AID while 37 (30.6%) had poor knowledge. Cadre of health professionals and marital status influenced the knowledge of respondents. Perceptions on AID varied among the respondents mostly influenced by psycho-social factors and possible legal disputes on third party reproductive process. None of the male respondents has ever donated semen and willingness to donate semen was low; with anonymity preferred by the willing donors.Conclusions: Substantial knowledge gap of AIDS existed among health professionals which were influenced by cadre and marital status. Psycho-social factors and possible legal disputes influenced their perceptions of AID

Challenges and Investment Opportunities for Large Scale Aquaculture Farmers in Nigeria

Fisheries sector plays an important role in Nigeria economy. Contribution of the sector to the nation's economy can be increased if challenges in the industry are minimized and the opportunities explored. Large scale aquaculture, an economic activity earning people a living is a very important industry encompassing fish traders, fish processors, fish farmers etc. The sector supports many Nigerians directly and indirectly. However fish importation is much more in quantity and value. 80% of aquaculture production in Nigeria is manned by small-scale farmers, except for few commercial ventures. Nigeria is blessed with numerous opportunities for large-scale aquaculture; however the challenges seem to override these opportunities. Constraints to production in the industry have been identified as recurrent high cost fish feed, poor water quality management, poor quality fish seed, technical know-how etc. Beyond the constraints to production are more pertinent factors responsible for un-sustainability of fish farm operation as business ventures. This paper focuses on the investment opportunities in large scale aquaculture and the current challenges that the farmers are facing in Nigeria. The paper shows that unprofitable operation of fish farms in Nigeria could be broadly attributed to two factors: poor production planning and inadequate technical know-how. The paper recommends the need to commercialize the industry through broad government fiscal efforts and sectorial re-organization in Nigeria

Influence of glyphosate on rhizosphere microorganisms and their ability to solubilise phosphate

Objective: To determine cowpea rhizosphere microor-ganisms with phosphate solubilizing potential in a soil treated with glyphosate. Methods: Four different con-centrations of glyphosate herbicides (0.00, 0.50, 1.00, and 3.00) were assayed. Cowpea seedlings were planted and later harvested after 30 days of germina-tion. Microorganisms from rhizosphere treated with glyphosate were cultured and identified using selective media Wakesman A and B agar. The activity of isolates were evaluated by Tricalcium phosphate solubilization and screening for phosphatase in a Pikovskaya me-dium.. Results: Bacillus cereus, Bacillus subtilis, Micrococ-cus luteus, Pseudomonas aeruginosa, Proteus mirabi-lis, Bacillus pumilis, Staphylococcus aureus, Aspergil-lus flavus, Rhizopus nigrifican, and Aspergillus sapro-phyiticus were obtained from the glyphosate treated soil. There was decrease in the bacterial and fungal population in the rhizosphere as glyphosate concentra-tion increased. The concentration of the solubilized Tricalcium phosphate ranged from 42.48 to 515.78gl-1. Micrococcus luteus, Bacillus subtilis, Proteus mirabi-lis, Aspergillus flavus, Aspergillus saprophyticus iso-lated at the different concentrations of glyphosate have increased phosphate solubilization with reduction in their pH. Proteus mirabilis showed the highest phos-phatase activity (23.157mM/min/ml) at 30hrs and As-pergillus saprophyticus showed highest phosphatase activity (35.263 mM/min/ml) at 72hrs. Bacillus sub-tilis had the lowest protein concentration (3.034mg/ml) at 12hrs. Conclusion: This study showed that these rhizosphere microorganisms when applied as inoculants into the soil at different concentration of glyphosate can help increase the availability of soluble phosphates

Application of gas chromatography mass spectrometry (GC-MS)-based metabolomics for the study of fermented cereal and legume foods:a review

A new era of cutting-edge technologies and advancements in analytical platforms and omics sciences is disruptively bringing a paradigm shift in fundamental and translational research. Metabolomics is one of the omics strategies that yields big data and has gained popularity in a wide spectrum of applications. Among various analytical platforms used in metabolomics, gas chromatography mass spectrometry (GC-MS) allows the measurement of thermally stable (volatiles and semi-volatiles) metabolites, with an advantage of spectral reproducibility. Cereal and legume-based fermented foods are part of the food culture in various countries throughout the world. Thus, this review provides an overview of recent applications of GC-MS-based metabolomics in the food fermentation field, specifically cereal and legume-based fermented foods. This emerging use of metabolomics in food fermentation studies illustrates the potentials of this omics science to elucidate metabolome landscapes of fermented foods. Such insights would advance our predictive understanding of fermentation processes and molecular descriptions of resultant food products; a necessary step for improvements and sustainability in food industry. Furthermore, the review echoes the current need of collaborative efforts in the scientific community (in this field) to harness and maximise the potentials of metabolomics in food fermentation studies

Effect of Technology-Enabled Video Instruction on Senior Secondary School Students’ Performance in Selected Technical Drawing Concept in Ilorin

The study examined the effect of technology-enabled video instruction (TEVI) on senior secondary school students’ performance in selected technical drawing (TD) concepts in Ilorin. The sample for this study consists of an intact class in a senior secondary school in Ilorin. The research adopted a mixed method of quantitative and qualitative research, pre-experimental research of one-group pretest-posttest design. Technology-Enabled Video was used for data collection. The findings from the study revealed that TEVI had a positive effect on the academic performance of students taught selected TD concept, (63.1˃ 51.5), there was a significant difference in the pretest and posttest performance of students taught selected technical drawing concept using TEVI i.e. (df=15, t=-565, p=.000˂0.05). The study concluded that technology-enabled video instruction which is an improvised instructional aid did enhance the academic performance of the students. The study implies that proper integration of technology-based packages like TEVI for instructional delivery will adequately enhance students’ performance. The study Recommended that TEVI should be encouraged among teachers and students, as this will help to boost learners’ interest and provide learners the ability to learn in a direct, self-paced, and individualistic manner, which will, in turn, translate to better academic performance

Combined effects of exogenous enzymes and probiotic on Nile tilapia (Oreochromis niloticus) growth, intestinal morphology and microbiome

A study was carried out to investigate the combined effect of exogenous enzymes and probiotic supplementation on tilapia growth, intestinal morphology and microbiome composition. Tilapia (34.56 ± 0.05 g) were fed one of four diets (35% protein, 5% lipid); one of which was a control and the remaining three diets were supplemented with either enzymes (containing phytase, protease and xylanase), probiotic (containing Bacillus subtilis, Bacillus licheniformis and Bacillus pumilus) or enz-pro (the combination of the enzymes and probiotic). Tilapia fed diet supplemented with enz-pro performed better (P < 0.05) than tilapia fed the control and probiotic supplemented diets in terms of final body weight (FBW), specific growth rate (SGR), feed conversion ratio (FCR) and protein efficiency ratio (PER). The dietary treatments did not affect somatic indices. The serum lysozyme activity was significantly higher (P < 0.05) in tilapia fed the probiotic supplemented diet than of those fed the remaining experimental diets. The intestinal perimeter ratio was higher (P < 0.05) in tilapia fed enz-pro supplemented diet when compared to those fed with the control and probiotic supplemented diets. Goblet cells abundance, microvilli diameter and total enterocyte absorptive surface was higher (P < 0.05) in tilapia fed diet supplemented with enz-pro than those fed the control diet. High-throughput sequencing revealed that majority of reads derived from the tilapia digesta belonged to members of Fusobacteria (predominantly Cetobacterium) distantly followed by Proteobacteria and Firmicutes. The alpha and beta diversities did not differ among dietary treatments indicating that the overall microbial community was not modified to a large extent by dietary treatment. In conclusion, supplementation of the diet with a combination of enzymes and probiotic is capable of improving tilapia growth and intestinal morphology without deleterious effect on the intestinal microbial composition

Principals’ perspectives on managing learner discipline in Secondary Schools

Abstract: This study explores principals’ perspectives on managing learner discipline in secondary schools. The study was located in a qualitative approach and employed a generic qualitative design. A literature study was undertaken to tap into the existing knowledge base on discipline, indiscipline and the causes and effects of indiscipline. Data was collected by means of semi-structured interviews with five secondary school principals. Qualitative content analysis was employed to analyse the data and subsequently three themes and various sub-themes emerged from the study. Findings indicate that learner discipline in secondary schools is in a poor state and is deteriorating. The study further revealed strategies that principals currently use to manage learner discipline. These include positive discipline and prevention, discipline structures in school, stakeholder involvement and the school’s code of conduct. Various challenges that principals face in managing learner discipline in schools were identified, which are inadequate parental involvement, ineffective parental skills in fostering discipline and insufficient support from the Department of Education...M.Ed. (Educational Leadership and Management