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Spodoptera eridania (Stoll), a polyphagous lepidopteran pest from the Americas, has recently invaded western and central Africa. Like its congeners, S. eridania has developed pesticide resistance. The rapid global spread and impacts of Spodoptera frugiperda (J.E. Smith) has raised concerns about whether S. eridania is set to do the same. Here we fit a CLIMEX niche model for S. eridania and apply a climate change scenario for 2050 to investigate the sensitivity of the pest threat. We find that S. eridania can potentially expand its range throughout the tropics and into the sub-tropics, threatening a range of important commercial and subsistence crops. An important feature of the pest threat posed by S. eridania is the extent of its ephemeral habitat during warmer months. Modelled climatic changes will mostly expand this species potential range poleward by around 200 km by 2050, indicating a moderate sensitivity. These areas of emerging potential expansion are mostly into subtropical climates, supporting diverse cropping systems, including at risk crops beans, groundnut, potato, soybeans, tomato and sweet potato. The potential distribution of S. eridania in the Amazon basin and the southern boundary of the Sahara Desert appear set to contract substantially due to increasing heat stress. While it may not be as invasive as some of its congeners, nor acquire pesticide resistance as readily, S. eridania does have some of these traits, and the current and emerging pest threat posed by this moth deserves closer attention, especially in relation to intercontinental phytosanitary measures to slow its spread.

Empirical evidence is scanty on the nexus between caregivers’ nutrition knowledge, market accessibility, and preschool children’s dietary diversity in remote communities of Africa’s most populous country, Nigeria. To fill this gap, this study evaluated the effects of caregivers’ nutrition knowledge and access to food market on dietary diversity of preschool children. We used cross-sectional data from four hundred households selected from twenty remote communities in Southeast Nigeria. The study adopted instrumental variable regression to estimate the impacts of nutrition knowledge and food market access on preschool children’s dietary diversity. The findings show that in remote communities, caregivers’ nutrition knowledge and households’ closeness to the market improved preschool children’s dietary diversity. The study demonstrates the potential of improving preschool children’s nutrition outcomes through enhancing access to food market and the nutrition knowledge of the caregivers.

This manuscript describes the particle size distribution based model.This model accounts for the degradation and methane production from the anaerobic digestion of the (OFMSW) organic fraction of municipal solid waste. The model also shows the reduction in cost of solid waste treatment. Analysis was done based on laboratory test, carried out to test the operating parameter such as Ammonia, PH, Temperature, volume of gas, total solid, volatile solid, nitrate, nitrite, phosphate and conductivity while Volatile fatty acid was negligible. The organic waste samples used was cow dung, and was digested using a continuous flow stirred reactor, which was constructed locally at the institution hydraulic laboratory. Results from the test and analysis reveals high concentration of ammonia which inhibited the production of gas. The total solid content was observed to determine the rate of organic loading of the reactor. The biogas production from the continuous flow reactor, contains ammonia concentration of 460mg/l ,385mg/l, 300mg/l, 193mg/l, 120mg/l and 130mg/l, under similar operating PH of 6.68. There was no contribution of biogas production from inoculation. Total volume of biogas produced was calculated and was found to be 0.036m3, 0.040m3, 0.055m3 0.053m3and varied according to PH range of 6.67 to 7.2. The result also shows that at a PH of 7.2, ammonia concentration was high, limiting the methane production rate. The highest form or concentration of nitrate and nitrite occurs at the end of the detention period. Decrease in the PH value and conductivity was a strong indication of the present of nitrate and nitrite in the solution of the waste sample.

The effects of climate change are evident worldwide, from melting ice caps at the Poles to deforestation at the tropics, and to rising sea level along the world's coastal margins. The cause is due largely to atmospheric greenhouse activities. The anthropogenic emissions from fossil fuel have altered the compositional balance of carbon dioxide (an important greenhouse gas) in the atmosphere. The spread of climate change impact is wide and affect lands and peoples across national boundaries. Among the threatened are people who inhabit the vulnerable lands such as coastal barrier lands, troughs between highlands, marshlands, etc. For generations, the people who live by the coast of Cross River Estuary and the tributaries of Calabar, Imo and Great Kwa Rivers in Nigeria have practised their fishing occupation without serious hitches. This situation has changed of late due to uncertainties associated with unpredicted flooding attributed mainly to climate change. This paper examines a scenario of the likely effe...

Le réchauffement climatique et les changements dans les régimes de précipitations sont parmi les principaux effets du changement climatique. Dans cette étude, la variabilité à long terme de la température ambiante de surface et des précipitations a été évaluée dans la région du centre-nord du Nigeria (Abuja, Kogi, Kwara, Niger et Plateau) à l'aide d'observations météorologiques obtenues entre 1975 et 2008. Les données quotidiennes sur les précipitations des stations météorologiques synoptiques ont été soigneusement contrôlées par la qualité à l'aide du RClimdex 1.1 développé par l'équipe d'experts sur la détection, la surveillance et les indices du changement climatique (ETCCDMI). L'ensemble de données à qualité contrôlée a été homogénéisé à l'aide de RHtestsV4 et les points de changement détectés ont été ajustés. Les résultats ont montré une diminution des nuits fraîches et des jours frais (TN10P, TX10P), et une tendance à la hausse des nuits et des jours chauds (TN90P, TX90P). La tendance des précipitations est variable par rapport aux changements de température. Les indices de précipitations ont indiqué une tendance à la hausse des précipitations annuelles totales (PRCPTOT) et une diminution significative du nombre de jours humides consécutifs (CWD) dans cette région. En général, les changements régionaux dans les températures climatiques et les précipitations extrêmes étaient significatifs (p<0,05) et pourraient entraîner de graves effets induits par le climat. El calentamiento global y los cambios en los patrones de precipitación se encuentran entre los principales efectos del cambio climático. En este estudio, se evaluó la variabilidad a largo plazo en la temperatura de la superficie ambiental y la precipitación en la región centro-norte de Nigeria (Abuja, Kogi, Kwara, Níger y Plateau) utilizando datos meteorológicos obtenidos entre 1975 y 2008. Los datos diarios de precipitación de las estaciones meteorológicas sinópticas se controlaron cuidadosamente utilizando el RClimdex 1.1 desarrollado por el Equipo de Expertos en Detección, Monitoreo e Índices de Cambio Climático (ETCCDMI). El conjunto de datos de calidad controlada se homogeneizó utilizando RHtestsV4 y se ajustaron los puntos de cambio detectados. Los resultados mostraron una disminución en las noches y días frescos (TN10P, TX10P) y una tendencia creciente en las noches y días cálidos (TN90P, TX90P). La tendencia de las precipitaciones es variable en comparación con los cambios de temperatura. Los índices de precipitación indicaron una tendencia creciente en la precipitación anual total (PRCPTOT) y una disminución significativa en el número de días húmedos consecutivos (CWD) en esta región. En general, los cambios regionales en la temperatura climática y las precipitaciones extremas fueron significativos (p<0,05) y podrían provocar graves efectos inducidos por el clima. Global warming and changes in precipitation patterns are among the major effects of climate change. In this study, the long-term variability in ambient surface temperature and precipitation were evaluated in the north central region of Nigeria (Abuja, Kogi, Kwara, Niger, and Plateau) using meteorological observations obtained from 1975-2008. Daily precipitation data from synoptic weather stations were carefully quality-controlled using the RClimdex 1.1 developed by Expert Team on Climate Change Detection, Monitoring and Indices (ETCCDMI). The quality-controlled dataset were homogenized using RHtestsV4 and the detected change points were adjusted. Results showed a decrease in cool nights and cool days (TN10P, TX10P), and increasing trend in warm nights and days (TN90P, TX90P). The trend in rainfall is variable compared to changes in temperature. The precipitation indices indicated increasing trend in total annual precipitation (PRCPTOT), and a significant decrease in the number of consecutive wet days (CWD) in this region. In general, regional changes in climate temperature and precipitation extremes were significant (p<0.05) and could result in serious climate induced effects. الاحترار العالمي والتغيرات في أنماط هطول الأمطار هي من بين الآثار الرئيسية لتغير المناخ. في هذه الدراسة، تم تقييم التباين طويل الأجل في درجة حرارة السطح المحيط وهطول الأمطار في المنطقة الشمالية الوسطى من نيجيريا (أبوجا وكوجي وكوارا والنيجر والهضبة) باستخدام ملاحظات الأرصاد الجوية التي تم الحصول عليها من 1975-2008. تم التحكم بعناية في بيانات هطول الأمطار اليومية من محطات الطقس الشاملة باستخدام مؤشر RClimdex 1.1 الذي طوره فريق الخبراء المعني بكشف تغير المناخ ورصده ومؤشراته (ETCCDMI). تم تجانس مجموعة البيانات الخاضعة للرقابة على الجودة باستخدام RHtestsV4 وتم تعديل نقاط التغيير المكتشفة. أظهرت النتائج انخفاضًا في الليالي الباردة والأيام الباردة (TN10P، TX10P)، واتجاهًا متزايدًا في الليالي والأيام الدافئة (TN90P، TX90P). الاتجاه في هطول الأمطار متغير مقارنة بالتغيرات في درجة الحرارة. أشارت مؤشرات هطول الأمطار إلى اتجاه متزايد في إجمالي هطول الأمطار السنوي (PRCPTOT)، وانخفاض كبير في عدد الأيام الرطبة المتتالية (CWD) في هذه المنطقة. بشكل عام، كانت التغيرات الإقليمية في درجات الحرارة المناخية وهطول الأمطار المتطرفة كبيرة (أقل من 0.05) ويمكن أن تؤدي إلى آثار خطيرة ناجمة عن المناخ.

Abstract The need to understand and proffer sustainable solutions to the persistent energy crises and energy starvation in Nigeria even in the face of abundant endowment of both renewable and fossil energy resources motivated this study. This study justified why solar energy should be accorded the highest priority as energy source in not only Nigeria but globally. A detailed review of the past, current and future status of solar integration in Nigeria is presented; it is seen that for grid-connected solar power integration the past status is nil, the current status is nil and future status may not be completely bleak as a number of Memoranda of Understanding have been signed. The existing supportive solar energy policies are highlighted and discussed; the chasm between the commendable Nigeria policy landscape and near-to-zero status of solar integration is blamed on poor implementation of the existing provisions by the Government. Recommendations were made on the basis of the existing policies and proposed policies. Additional provisions to some of existing laws of the Federation to accommodate support for solar energy integration are suggested. It is recommended that the poor and incipient status of solar integration in the vastly populated Nigeria should be viewed in a positive light by potential foreign investors as such status is a guarantee that solar power and thermal industry is a firsthand investment opportunity.

AbstractThe present study investigates three different fuels such as gasoline, liquefied petroleum gas (LPG), and syngas in spark‐ignition Honda GX270 Genset engine under wide‐open throttle position on its performance, combustion characteristic as well as availability analysis. The results showed that when the engine operated with gasoline fuel, the brake thermal efficiency was higher than that of LPG and syngas by 6.2% and 7.4%, respectively, throughout the engine load condition. Brake‐specific fuel consumption of the engine with syngas (660 g/kW h) and LPG fuel (812 g/kW h) was higher than that of the gasoline fuel (510 g/kW h) at the 4.5 kW of engine load. The engine emission results showed syngas operation caused a significant reduction in NOx by 58.4%, CO by 16.5%, HC by 23.2% compared to gasoline fuel at peak load conditions. On the other hand, exergy analysis concludes the exergy efficiency for all the test fuels increases with an increase in engine load due to a high rise in shaft output. At a 4.5 kW power output, the exergy efficiency of the engine was improved to 46.45% from 45.62% and 29.73% with syngas, gasoline, and LPG, respectively. The maximum exhaust gas availability has been observed as 24.51% of availability input for syngas at 100% load condition.

Crude oil, which was first discovered in Nigeria in 1956 by the Shell-BP Development Company, has contributed significantly to the country's economic development. The exploitation of this resource transformed Nigeria's balance of trade from chronic deficits to huge surpluses (especially during the early-to-mid 1970s). This occurred as a result of the increase in the volume as well as the value of crude oil during this period. However, the surplus started to decline in the mid-1970s due to a combination of increased imports (resulting from the oil-boom mentality that had developed) and reduced crude oil exports (caused by the downward trend in world economic situations). By late 1977 the country again had a deficit on visible trade.

AbstractInvestigations are reported on high‐ and low‐temperature vulcanized silicone rubber composite insulators that were exposed to service for three, nine and eleven years under industrial or marine pollution conditions. Wetting angles and thermally stimulated depolarization (TSD) current spectra were measured. Microscopic observations of selected insulator surfaces were carried out as well. The prolonged services cause gradual and inhomogeneous losses of hydrophobicity on surfaces and inside of insulator housing materials. It is shown that there exists a correlation between the measured TSD current spectra and the wettability changes. In addition, the spectra also allow to predict an ability to support a process of hydrophobicity recovery at a housing surface. It seems that TSD measurements may be applied as a complementary test method during performance assessment of silicone rubber composite insulators.