MACROECONOMIC SHOCKS, HUMAN CAPITAL AND PRODUCTIVE EFFICIENCY: EVIDENCE FROM WEST AFRICAN FARMERS

Little empirical work has quantified the transitory effects of macroeconomic shocks on farm-level production behavior. We develop a simple analytical model to explain how macroeconomic shocks might temporarily divert managerial attention, thereby affecting farm-level productivity, but perhaps to different degrees and for different durations across production units. We then successfully test hypotheses from that model using panel data bracketing massive currency devaluation in the west African nation of Cote d'Ivoire. We find a transitory increase in mean plot-level technical inefficiency among Ivorien rice producers and considerable variation in the magnitude and persistence of this effect, attributable largely to ex ante complexity of operations, and the educational attainment and off-farm employment status of the plot manager.Labor and Human Capital, O1, Q12, Q18,

Design and Simulation of 1.28 Tbps Dense Wavelength Division Multiplex System Suitable for Long Haul Backbone

Wavelength division multiplex (WDM) system with on/off keying (OOK) modulation and direct detection (DD) is generally simple to implement, less expensive and energy efficient. The determination of the possible design capacity limit, in terms of the bit rate – distance product in WDM – OOK –DD systems is therefore crucial, considering transmitter/receiver simplicity, as well as energy and cost efficiency. A 32-channel WDM system is designed and simulated over 1000 km fiber length using Optsim commercial simulation software. The standard channel spacing of 0.4 nm was used in the C–band range from 1.5436 to 1.556 nm. Each channel used the simple non return to zero – on/off keying (NRZ – OOK) modulation format to modulate a continuous wave (CW) laser source at 40 Gbps using an external modulator, while the receiver uses a DD scheme. It is proposed that the design will be suitable for long haul mobile backbone in a national network, since up to 1.28 Tbps data rates can be transmitted over 1000 km. A bit rate length product of 1.28 Pbps.km was obtained as the optimum capacity limit in 32 channel dispersion managed WDM – OOK – DD system

Swarming modulatory effects of some amino acids on Proteus strains from Lagos, Nigeria

Swarming motility, a multicellular behaviour characterized by periodic concentric growth on solid media has severally been reported as a constraint in the clinical investigation of mixed-culture infections involving Proteus and as a requirement for virulence. While media are being formulated to restrain swarming in this organism, the roles played by amino acids in the biogenesis of swarming have not been fully clarified. The effects of 20 amino acids on swarming, extracellular protease activity, cellular RNA level and total protein concentration in 20 clinical Proteus strains from Lagos, Nigeria were investigated. At 0.5mM concentration, glutamine, serine, and methionine were the only amino acids found to enhance swarming motility on M9 minimal medium (7.1—11.3 mm), cause significant increases in protease activity (33.7—48.3 units/ml), total protein concentration (22.5—28.6 mg/ml) and cellular RNA concentration (192.8—264.7 mg/ml) when compared to values obtained for other 17 amino acids (P < 0.05). Furthermore, the amino acid induced swarming in these strains was found to vary directly and significantly (P < 0.05) with protease activity and cellular RNA concentration. The exclusion of methionine, serine and glutamine when supplementing antiswarming media for clinical investigation of Proteus - associated polymicrobial infections in Nigeria is suggested. (African Journal of Biotechnology: 2002 1(1): 10-16

Aerosols Loading Trends and its Environmental Threats Over Cotonou-Benin.

Environmental security is totally relegated in countries of West Africa. The monitoring of the aerosols loading over Cotonou was the aim of this study. The outcome of our finding has salient links to food security, aviation and communication industry, thermal comfort and climate system of Benin. Cotonou is located on longitude 2.43°E and latitude 6.37°N. Fifteen years data were obtained from the multiangled spectro-reflectometry (MISR). The aerosol loading was monitored using analytical and statistical techniques. The aerosols retention over Cotonou was high in 2000 (69.91%), 2008 (72%) and 2013 (42.45%). This means that there is the possibility of higher rising sea levels and exposure to coastal erosion due to a twisted cloud formation

Rain Induced Cross Polarization on Satellite Communication in Nigeria

Microwave systems performance on satellite communication link operating above 10 GHz is increasingly degraded by rain when designing telecommunication systems. Cross polarization is one of the major source of signal degradation that affectthe frequency reuse when employed to boost capacity of the channel. The effect of cross-polarization in thirty-seven (37) stations in Nigeria were carried out using 10 years data obtained from Nigeria Meteorological Agency (NIMET) at the look angle from Nigeria Communication Satellite (NigComSat). International Telecommunication Union-Recommendation (ITU-R) model was used to for this study. The stations were grouped into six geopolitical zones in Nigeria which are Southwest (SW), Southeast (SE), South-south (SS), Northcentral (NC), Northwest (NW) and Northeast (NE). The results reveal that cross-polarization discrimination (XPD) become very poor as frequency (at Ku-band, Ka-band, V-band) increases especially at lower percentage of time (such as 0.001%, and 0.01%) unavailability. Hence XPD, at all frequencies is poorer in the southern part of Nigeria SE, SS and SW due to high rainfall rate. The results also show that only Northern part of the country will experience no interference at 0.01% as XPD is over 30 dB ITU-R base line for Ku-band transmission. However, for Ka-band and V-band at 0.001% and 0.01% unavailability of time interference will occur in all stations in Nigeria, but at 0.1% and 1% XPD is over 30 dB for all stations. This study will help in the adequate planning and designing of satellite telecommunication expansion in all the six geopolitical zones in Nigeria

Dynamics of Wind Strength and Wind Direction on Air Pollution Dispersion

The aim of the study is to examine the wind dynamics of Ota to understand certain atmospheric influences. An average volume of about four hundred and eighty thousand (480,000) wind speed data from the Davis weather station data logger of the department of physics, covenant university were considered. The data studied were divided into eight hour period, namely, night time (10pm to 6am following day); day time (6am to 2pm) and noon/evening time (2pm to 10pm). Of the three periods studied, wind speed at night time was observed to be the least. December, January and February (DJF) data set was statistically analyzed. The correlation coefficient values recorded with the wind flow for the months of DJF are 0.28 for December, 2012, 0.20 for January, 2013, and 0.39 for February, 2013. While a significant low correlation coefficient values observed for the months of March, April and May (MAM) are 0.02 for March, 0.01 for April and 0.04 for May. A further daily analysis was conducted for February. A significant occurrence of atmospheric stagnation was observed in the night time readings of February 3, 2013 with an exceptional low average wind speed of 0.143 ms-1. While February 17, 2013 recorded all day normal air ventilation with wind speed of 1.443 ms-1, 1.998 ms-1, 4.482 ms-1 for night, day and noon/evening time respectivel

Theoretical Study of Aerosols Loading and Retention Over Bolgatanga, Ghana

The aerosols loading and retention over West Africa have grave effect on life-forms through the impact on health, farming, rainfall pattern, cloud formation, and regional climate. Bolgatanga can be found on the latitude and longitude of 10.78°N and 0.85°W, respectively. This research is focused on an investigative consideration of the negative effect of atmospheric aerosols over Bolgatanga in Ghana through a conceptual model using analytical and descriptive statistical methods with MATLAB curve-fitting tool. The model was verified using aerosol optical depth data set from satellite imagery—multi-angle imaging specto-reflectometer (MISR)—obtained over a period of 13 years. The highest percentage increase of aerosol retention was 64.27% over the research site. The model was used to estimate the atmospheric constants as 0.67, tuning constants as 0.24, and phase difference as ± π 4 . The physical interpretation of the results was analyzed systematicall

Low Cost Real-Time Portable Pulse Oximeter with Wireless Network

To facilitate quicker detection of symptoms of cardiovascular and respiratory disorders, the use of smaller portable wireless sensors which consume less power is an essential requirement. Wireless pulse oximeter are convenient devices which aid to remotely monitor a patient’s heart rate and blood oxygen saturation (SpO ), The result of this studyshows a developed portable, low cost device which can be used to measure the heart rate, and SpO of an individual. To this end, a small pulse oximeter was developed; which used an elastic transmissive mode finger probe to measure the heart rate and SpO . The device could successfully measure these vital signs and display on a LCD screen. The readings taken from individual for a period of one minute shows average heart rate of 75.6 bpm at zero offset and the average SpO readings derived from the device was 98.7% at zero offset. The model designed is also rechargeable to make it more sustainable for use in rural areas where there is insufficient power supply. The prototype pulse oximeter designed is portable, consumes less power and capable of sending processed measured data to an online database via a WLAN network thereby satisfying the criteria for sustainable telemedicine.This device is therefore recommended for use in local hospitals and remote medical centre to aid easier detection and prevention of critical medical disease

Effects of lead nitrate on the geotechnical properties of lateritic soils

This study explored the effects of lead (II) nitrate on the geotechnical properties of two soil samples. The geotechnical properties of the natural soil samples were determined prior to their contamination with lead nitrate. The samples were then contaminated with 500 ppm, 1000 ppm and 2000 ppm of lead (II) nitrate and cured for 1, 14 and 28 days. The geotechnical properties of contaminated soil samples were determined after each of the curing periods. Results show that the maximum dry unit weights of the samples generally reduced with increasing concentration of lead nitrate and with increasing curing period. The optimum moisture contents of the samples increased with increasing curing period but reduced with increasing concentration of lead nitrate. However, an increase in the CBR after 28 days curing period was noticed for the samples as the concentration of the lead nitrate increased. The contaminated soil samples are suitable for use as subgrade and subbase materials for road pavement construction

PEDAGOGIC REPOSITIONING OF CURRICULUM IN ARCHITECTURE AND CIVIL ENGINEERING EDUCATION TO MEET INDIGENOUS NEEDS

Inadequate provision for required Traditional Knowledge (TK) is identified as a weakness in the educational curricula that seek to birth adequately-trained and well-motivated professionals with the capacity to pragmatically solve local problems with indigenous technology. The focus of this paper is to review the present curricula of Architecture and Civil Engineering courses, identify the gaps and recommend how they can be filled. The current pedagogical approaches and curriculum contextrelevance employed at the Architecture and Civil Engineering Departments of Covenant University Ota, Nigeria were evaluated. Specific references were made to project-based courses that involve architecture and civil engineering. Lectures, site visits, participatory projects and workshops were identified as means of building the capacity of young professionals and students towards the acquisition of the required TK and other relevant skills. It is expected that a successfully-integrated indigenous design would connect all relevant sustainable indices of the design together at different levels. In this way, the sustainability indices of (energy-efficient) designs, construction and maintenance of infrastructure in the built-environment industry would not be compromised. The study recommends the incorporation of all critical elements of traditional based curricula development for best practices that will promote indigenous architecture and civil engineering education for future professional