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Carbapenemase-producing (CPEC) has been an issue of public health concern due to high resistance to major antibiotics. This pathogen can be acquired through the consumption of contaminated foods. The use of detergents for the control of pathogens in food contact surfaces is commonly practiced by most food vendors. This study is aimed at assessing the efficacy of some commonly used detergents against CPEC from food contact surfaces in Nasarawa State, Nigeria. A total of 924 swab samples from food contact surfaces (246 each from plates, cups and spoons and 186 from tabletops) in various food vending outlets were screened for phenotypic identification of CPEC using Imipenem (30µg) and Meropenem (10µg) antibiotics susceptibility disk diffusion method. Tubes of varying concentrations of test detergents (1:140, 1:160, 1:180, 1:200 and 1:220) were seeded against phenol as standard with varying concentrations of 1:50, 1:60, 1:70 1:80 and 1:90. Hawkers outlets had highest CPEC isolation frequencies among swab samples and isolates with values of 3.33% and 7.70% respectively while cups and spoons surfaces had highest samples (1.63%) and isolates (7.69%) frequencies respectively. Overall CPEC isolation frequencies were 1.30% and 6.00% among the screened samples and isolates respectively. Though there was significant difference (p0.05. Highest phenol coefficient value of 2.6 was obtained for MFD while SLD and LPD had 2.3 and 1.7 respectively. The difference in the phenol coefficient values among the detergents were statistically insignificant (p>0.05). All detergents used in this study were effective against CPEC isolated from the food contact surfaces. Using locally produced detergents in appropriate concentrations especially for low-income earners is quite promising and is a good alternative to other branded detergents.

The study presents an optimal design of simply supported rectangular reinforced concrete beams based on the ultimate limit state philosophy of BS8110 and using genetic algorithm as optimization tool. An optimization model was formulated. The model consists of an objective function which focuses on minimizing the steel ratio of the beams and constraint equations which are focused on checking that all the requirements of BS8110 for the design of reinforced concrete beams are satisfied. Results obtained showed a difference of up to 46% and 12.6% in steel ratios obtained using the traditional approach and those obtained using the optimization model for singly and doubly reinforced concrete beams respectively, depending on the magnitude of the applied moment. The model has proved to minimize the final dimensions of rectangular reinforced concrete beams and by implication, the steel ratio even though all the requirements of the code were satisfied.

Climate change is a global environmental threat, affecting every sector of the economy with agriculture being the most affected as a result of its dependence on climate especially rainfall and temperature. The objective of this study is to examine the impacts of climate change on agriculture (crop production) and identify the farmers’ adaptation strategies to the impacts of climate change in Senegal. This study employed systematic literature review. Searching of relevant documents were conducted between 26th December 2020 and 10th February, 2021. A comprehensive search of six databases were conducted. The databases searched were Scopus, African Journal Online (AJOL), ProQuest, Elsevier, Research gate, and Google scholar. The findings revealed that temperature is expected to increase by median value of 0.90C (0.70C-1.50C) by 2035, by 2.10 (1.60C-3.30C) by 2065, and 4.00C (2.6-5.90C) by 2100 and rainfall could increase by 1% (uncertainty range of −4% to +8%) by 2035, 2% (−8% to +8%) by 2065, and 5% (−10% to +16%) by 2100. As a result of rising temperatures, local agricultural production will be less than 50kg per capita by 2050. This is expected to have an effect on crop imports as well as regional migration. The decrease in rainfall under RCP2.6, (Representative Concentration Pathway) combined with the effect of temperature, has a significant impact on the yield of sorghum, maize, and millet, with production decreasing by up to 20-50%. Farmers employed several adaptation strategies to adapt to the impacts of climate change; sowing improved variety, mixed cropping, income diversification, ownership of multiple farms, religious practices in form of prayer. The review recommends strengthening of climate related institutions, adoption of new innovations, implementation of new climate related policies, climate monitoring and forecasting, enhancing and strengthening community-based adaptation through sensitization and incentives.

Despite the several kinds of literature on the dispersion behaviour of supercritical CO2 in CH4 at conditions relevant to enhanced gas recovery (EGR), studies have so far limited in keeping this parameter as low as possible. This study aims to highlight, experimentally, to determine the effect of N2 as cushion gas on the dispersion coefficient in consolidated sandstones core plug under reservoir conditions applicable to EGR. A laboratory core flooding experiment was carried out to simulate a detailed process of an unsteady state methane displacement in Bandera gray and Bentheimer core plugs at reservoir conditions of 40oC temperature, 1500 psig of pressure, the optimum injection rate of 0.4ml/min, and at varying N2 cushion volumes (8-36 cm3). Further experimental runs were carried out to investigate the effect of high CO2 injection rates (0.6-1.2 ml/min) on the longitudinal coefficient of dispersion as it plumes transverses into the core plugs during the EGR process. The coefficient of longitudinal dispersion declines with raises in cushion gas volume, hence the higher the amount of N2 cushion volume the less the dispersion of CO2 into CH4. This is due to the high shielding barrier inhibited by nitrogen, making it difficult for the CO2 to dispersed itself and mixed with the nascent natural gas resulting in delayed breakthrough as it plumes transverses into the CH4 during the displacement process. The inclusion of N2 as cushion gas prior to CO2 injection recorded the highest decline at 36cm3 cushion volume, presenting a 48 and 28% reduction in longitudinal dispersion coefficient for Bandera and Bentheimer core samples respectively, compared to that of conventional/traditional CO2 injection (with zero cushion volume). Recording lower nascent CO2-CH4 mixing resulting in less natural gas contamination and more storage volumes. Also, a reverse phenomenon was observed when the CO2 injection rate was increased from 0.6-1.2 ml/min due to the high diffusion rate of CO2 at higher interstitial velocities, resulting in a rapid increase in dispersion coeffient and indirectly high widespread contamination of the remaining natural gas.

The use of carbon dioxide (CO2) for simultaneous methane recovery and CO2 storage is gaining recognition globally within the oil and gas industries. On the other hand, most of the residual natural gas recovered during the EGR process is highly contaminated with the injected CO2 due to their nascent miscibility nature, resulting in premature breakthrough. In this study, N2 gas was used as a buster to mitigate such early mixing between the CH4 and CO2. The experiment was administered at reservoir conditions of 40oC temperature, 1500 psig of pressure, the optimum injection rate of 0.4ml/min, and at varying N2 cushion volumes (8-36 cm3) using Bandera gray as the porous medium. Further experimental tests were administered to study the effect of this technique on connate water salinity with 5-20% water salinity been considered. The increase in buster gas volume was in direct proportion to delayed CO2 breakthrough, with the maximum at 36cm3 buster volume. This breakthrough occurred at 177 minutes which is 110min additional delayed than the conventional CO2 flooding with a breakthrough time of 67 minutes. This was due to the high shielding barrier inhibited by nitrogen, making it difficult for the CO2 to dispersed itself and mixed with the nascent natural gas resulting in delayed breakthrough as it plumes transverses into the CH4 during the displacement process. Furthermore, a poor performance was observed with the inclusion of the connate water salinity, especially at 20% wt. This was because the free pore spaces were already occupied by connate water molecules prior to the cushion gas injection which hinders its economic potential application.

Inoculation of promiscuous soybean with rhizobia has been proven to improve yield. Screenhouse pot experiments were conducted to assess the response of promiscuous soybean, TGx1448-2E to rhizobia inoculation and to determine the relative efficiency of indigenous rhizobia from soils collected from the Northern and Southern Guinea and Sudan Savanna agro-ecological zones of Nigeria. Soils were collected at 0 to 20 cm depth from 45 sites spread in 15 local government areas of Kaduna and Kano states. The treatments used were uninoculated control, mineral nitrogen and Legumefix, a commercial rhizobia inoculant which were arranged in randomized complete block design and replicated three times. Nodulation and biomass were assessed at eight weeks after planting. Response to inoculation and relative efficiency were also determined. The results showed that response to inoculation was higher in the Sudan Savanna than in the Northern Guinea Savanna. These were observed in 12 out of 21 and 9 out of 19 sites in the Sudan Savanna and Northern Guinea Savanna, respectively. Of these, inoculation response reached 62 and 90% in two sites in the Sudan Savanna while it barely reached 20% in the remaining sites. The results also showed a relative efficiency which is greater than 100% in some locations. This implies that the indigenous rhizobia populations were superior to mineral nitrogen and Legumefix inoculant. Notable among the locations were ALB 1, GRK 1, SOB 4 and KOL, which spread across all the agro-ecological zones. Strains from such locations have high potential for use as inoculants. Key words: Legumefix, mineral nitrogen, inoculation, indigenous strains, agro-ecological zones.