Application of Synthetic Storm Technique for Diurnal and Seasonal Variation of Slant Path Ka-Band Rain Attenuation Time Series over a Subtropical Location in South Africa

As technology advances and more demands are on satellite services, rain-induced attenuation still creates one of the most damaging effects of the atmosphere on the quality of radio communication signals, especially those operating above 10 GHz. System designers therefore require statistical information on rain-induced attenuation over the coverage area in order to determine the appropriate transmitter and receiver characteristics to be adopted. This paper presents results on the time-varying rain characterization and diurnal variation of slant path rain attenuation in the Ka-band frequency simulated with synthetic storm techniques over a subtropical location in South Africa using 10-year rain rate time-series data. The analysis is based on the CDF of one-minute rain rate; time-series seasonal variation of rain rate observed over four time intervals: 00:00–06:00, 06:00–12:00, 12:00–18:00, and 18:00–24:00; diurnal fades margin; and diurnal variation of rain attenuation. Comparison was also made between the synthesized values and measured attenuation data. The predicted statistics are in good agreement with those obtained from the propagation beacon measurement in the area. The overall results will be needed for an acceptable planning that can effectively reduce the fade margin to a very low value for an optimum data communication over this area

Dividend Policy and Shareholders’ Wealth in Nigerian Quoted Banks

In 2008, the global financial meltdown was partly responsible for the bearish movement of stock prices in the Nigerian Stock Exchange. This shows that more than a single factor could be responsible for the movement of prices of quoted stocks. Company performance and information about the introduction of new technologies are among the factors that have significantly affected the market value of shares in the past. Therefore, this paper examines empirically, the implications of adopted dividend policies on the value of shareholders’ wealth and the extent to which dividend policy affects the market value of shares in quoted banks in Nigeria. The paper focuses on the situation before and after the financial meltdown. Correlation results of dividend paid in 2007-2010 and their corresponding market value showed that payment of dividend by quoted banks is relevant to their market value and the amount paid as dividend affects the value of their share. The paper also provides insight into the implications and effect’s of policy decisions as it affects dividend payout and dividend retained for further growth on shareholders’ wealth

Genetics evaluation of phosphorus utilization in tropical cowpea (Vigna unguiculata (L) Walp)

Genetics evaluation of phosphorus utilization in cowpea (Vigna unguiculata (L) Walp) was studied in a cross involving a tropically adapted genotype (IT90K-277-2) with a reported positive response to rock phosphate (RP) and a second genotype (IT89KD-288) that responds negatively to RP, using generation mean analysis of the parents, their F1, F2 and the two backcross generations. Highly significant differences among the six generations with respect to seed phosphorus (P) concentration and grain yield per plant were observed. The F1 progenies produced seeds with higher seed P concentration (0.31 mg/g) than the mid-parent value (0.27mg/g). Mean yield per plant in the F1(48.03g) that was significantly greater than the mid-parent value (28.85g) was also observed suggesting positive heterosis for the two traits. Backcrossing to both parents showed good convergence of genes on the recurrent parents. Possibility of transgressive segregation for seed P concentration and grain yield per plant in the F2 generation was also observed. Absence of significant reciprocal differences among individuals in the F1 and F2 populations suggested lack of maternal and cytoplasmic effects. Non-additive gene action (dominance and epistasis) made significant contributions to total genetic variations in both traits within the cross. Whereas seed P concentration was observed to be under polygenic control, number of genes for seed yield per plant was biased downward by epistasis. Observed narrow-sense heritability estimate (HN)) for seed P concentration of 50.51% and very low (0.040) expected genetic gain in the F3 over the F2 means suggested that although expected progress from selection could be lowered by non-additive gene effects, this trait could be transmitted to the offsprings of hybridization program with huge success, through backcrossing. Although, available soil P (6.03 – 8.09mg/kg) was observed to be below the critical level, phosphorus uptake in the F1 and the segregating generations was observed to be higher than what obtained in the parents to suggest that the progenies of a P-efficient x P-inefficient cross would be efficient in P utilization.Keywords: Generation mean analysis, Phosphorus uptake, Polygenes, Transgressive segregants, Tropical vigna

Iris feature extraction: a survey

Biometric as a technology has been proved to be a reliable means of enforcing constraint in a security sensitiveenvironment. Among the biometric technologies, iris recognition system is highly accurate and reliable becauseof their stable characteristics throughout lifetime. Iris recognition is one of the biometric identification thatemploys pattern recognition technology with the use of high resolution camera. Iris recognition consist of manysections among which feature extraction is an important stage. Extraction of iris features is very important andmust be successfully carried out before iris signature is stored as a template. This paper gives a comprehensivereview of different fundamental iris feature extraction methods, and some other methods available in literatures.It also gives a summarised form of performance accuracy of available algorithms. This establishes a platform onwhich future research on iris feature extraction algorithm(s) as a component of iris recognition system can bebased.Keywords: biometric authentication, false acceptance rate (FAR), false rejection rate (FRR), feature extraction,iris recognition system

Diallel analysis of maize inbred lines for agronomic traits in nitrogen stress and optimal conditions

Increasing demand, soil cultivation pressure and adverse climate change effects necessitated maize production in nitrogen stress soils. This study examined the general combining ability (GCA) of 12 maize inbreds and specific combining ability of their crosses for agronomic traits under varied nitrogen conditions. GCA accounted for 53% of the variation for grain yield (GY) under stress and 40% under optimal condition. GCA contributed over 59% for days to anthesis (DTA) and days to silking (DTS), anthesis-silking-interval (ASI) and ear aspect (EASP) under both conditions. BD74-165 and BD74-161 had positive significant GCA for GY under stress with TZEI12 under optimal and BD74-222 under both conditions. TZEI13 and TZEI16 had positive significant GCA for DTA and ASI under stress, and TZEI12, TZEI11 and BD74-161 under optimal. Additive genes control DTA, DTS and PH; non-additive genes were responsible for ASI, PASP and EASP while both additive and non-additive genes governed inheritance of GY, EH and leaf-senescence (SEN) under stress. Inheritance of GY, ASI, PH, PASP and EASP were due to non-additive genes; DTA and DTS to additive genes while additive and non-additive genes control EH and SEN under opti­mal condition. Inbreds with significant GCA can be parents for GY improvement under respective conditions. Keywords: Combining ability; diallel; low nitrogen; maize lines; stress toleranc

Student Perceptions of Problem Topics/Concepts in a Traditional Veterinary Embryology

Even though particular attention is paid to the nature and content of anatomy curricula, little has been published about the actual problem topics/concepts experienced by students of anatomy. This information is relevant to modifying existing courses and methods of teaching. The present study thus sought to identify, by means of a questionnaire administered to students of veterinary anatomy, perceived problem topics, the possible reasons for the problems, as well as student suggestions for solving the problems. A wide range of problem topics were identified by this survey, of which the development of heart and cardiovascular system, development of face/head, foetal membrane/placentation particularly 3 D pictures and then the development of body form and urogenital (including external genitalia) recurred most frequently. A major reason given for the problems experienced was an inability to conceptualise 3-dimensional structures. Students requested more time, more lectures and appealed for a reduction in detail of textual information. Many of the problems experienced by this group of students are reflected in other studies of veterinary, medical and dental students, which suggests the existence of ‘universal’ problem topics in the various fields of anatomy. We believe that these universal problem topics exist in many anatomy courses, despite the application of innovative teaching methods and advanced audio-visual technologies. Only by identifying these topics can suitable strategies (within the constraints of the particular curriculum) be devised to resolve them.Keywords: Anatomy, Embryology, Histology, Problem Topics/Concepts, Student Perceptions

PERFORMANCE EVALUATION OF TROPICAL BIOFUELLED FISH SMOKING STRUCTURES

Environmental and hygienic concerns associated with traditional fish smoking structures restrict the sale and consumption of smoked products to local markets. This study evaluated the performance of three(improved kiln oven (IKO), mud-type ovens (MTO) and extended drum ovens (EDO)) locally available Biofuelledfish smoking structures and proposed modifications to improve product quality.Three groups of prepared freshwater catfish (Clarias gariepinus) with average live weights of 1.93 kg±46 g, 1.92 kg±50 g and 1.86 kg±50 g was used as test samples. Smoking profiles, final moisture content (FMC), smoking time, smoking temperatures, percentage weight loss (WL) and organoleptic evaluation (ORE) were the performance indicators used during evaluatio

Differences in digital health literacy and future anxiety between health care and other university students in England during the COVID-19 pandemic.

Background: This study investigates university students' digital health literacy and web-based information-seeking behaviours during the early stages of the COVID-19 pandemic in England. It compares undergraduate and postgraduate students in non-health related subjects with health care students, many of whom were preparing for, or working in, frontline roles. The survey was conducted as part of a wider study by the COVID-HL research consortium. Methods: A cross-sectional study was conducted among n=691 university students aged ≥18 years from 25 universities across England using an adapted digital survey developed by COVID-HL. Data were collected regarding sociodemographic characteristics and specific measures drawn from the Future Anxiety Scale and the Digital Health Literacy Instrument (DHLI). These had been adapted for use in an English setting and to the specific context of the COVID-19 pandemic. Other data collected included students’ anxiety or worries about the future using the Dark Future Scale as well as behaviours in online information-seeking. Data were analysed using correlations to test for relationships between constructs and also between group comparisons to test for differences between students studying health and non-health related subjects. Results: Across digital health literacy dimensions, there was no significant difference between students studying health-related subjects and other students. Health care students did report greater difficulties in relation to how to behave online. They also relied less on public body sources for information about the pandemic. A significant difference was found between the two student populations in relation to their anxiety about the future with health care students reporting fewer fears about the future. Conclusions: Although digital health literacy is well developed in university students, a significant proportion of students still face difficulties with evaluating online information which may frustrate public health efforts. This could be addressed by ensuring health students’ curriculum in particular encompasses digital health literac

The effect of farmyard manure and urea on grain yield and agronomic characteristics of maize (Zea mays)

Combining organic and inorganic fertilizer has been proved to be an effective and sustainable soil management strategy for increased crop yield and safe environment. Field experiments were conducted in two locations in Nigeria namely Malete and Shao during 2018 and 2019 seasons. This was to find out the efficacy of organic and inorganic fertilizer (including prilled and granular urea) and their various combinations on grain yield and agronomic characteristics of maize. The use of full dose of P and K + 75% N through Granular Urea + 25 % N through farmyard manure improved most of the soil chemical properties with high economic returns. It was concluded from the experiment that a combination of organic and inorganic fertilizers is an environmentally friendly practice and could lead to high yields and improve farmers’ income and their livelihoods