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The study focuses on the evaluation of the impact of acid rain on some common roofing sheets, including; Stone Coated, Galvanized, 0.55 m and 0.45 mm Long Span , Aluminum/Zinc sheet  using simulated acid rain. The simulated acid rain was from four different molar concentrated H2SO4 and HNO3. The parameter used for the evaluation was a weight loss of the roofing sheet over the study period. Gravimetric analysis technique was adopted for the study. At the end of the study, the result obtained showed that for 1 mole solution H2SO4, 0.45 mm long Span recorded the lowest weight loss of 0.43 g, followed by Cameroon zinc with loss of 0.46 g while 0.55 mm long Span recorded 0.63 g. Stone-coated and galvanized sheet melted up before the end of the experiment. 1 mole solution of HNO3 recorded a similar trend with 0.46 g, 0.36 g, 0.47 g and 3.95 g weight loss for 0.55 mm long Span, Cameroon Zinc, 0.45 mm Long Span and stone Coated sheet respectively while Galvanized sheet melted up before the experiment ends. Stone Coated and Galvanized sheet melted up before the end of the experiment in 0.5 mole H2SO4 while 0.45 mm Long Span, 0.55 mm long span and Cameroon Zinc recorded 0.47 g, 0.5 g and 0.35 g weight loss respectively. Only Galvanized sheet melted up in 0.5 mole of HNO3, 3.5 g, 0.28 g, 0.38 g and 0.3 g weight loss was recorded for stone coated sheet, 0.45 mm long Span, 0.55 mm long Span and Cameroon Zinc respectively. Polynomial model of the fourth order show the best fit for the data. The models obtained for the weight loss and rate of corrosion showed a good fit with R2's ranging from 0.9 and above except for stone coated and galvanized sheets in 1 mole solution of H2SO4 with R2 of 0.782 and 0.8142. It is worthy to note from all the results obtained from the research that high percentage Aluminum base roofing sheet is the best for H2SO4 and HNO3 polluted environment.

Extraction and characterization of carrier oil has been conducted experimentally on coconut, avocado and carrot oil. FTIR scan analysis was carried out on the extracted oil. Also physical and chemical properties of the carrier oils were assessed to evaluate oil quality including Specific gravity, peroxide value, saponification value, acid value and free fatty acid. The result showed all the extracted oils were liquid at room temperature an indication of the presence of oleic acid and linoleic acid and other unsaturated fatty acids. The specific gravities of 0.92, 0.91 and 0.93 for coconut, avocado and carrot oils indicate that each of the oils could be used on commercial scale. The Peroxide value recorded 0.11-0.12 meq/kg which is far below the maximum limits of 1-5 meq/kg and can last for a long time without going rancid. The low saponification values of coconut, avocado and carrot oils  of 127.62 meq/kg oil, 120.12 meq/kg oil and 130.47 meq/kg oil respectively indicates that the oils could be used industrially (soap making). An iodine value of 54.63g I2/100g coconut oil, 49.21g I2/100g avocado oil and 55.01g I2/100g carrot oil obtained indicates high level of unsaturated fatty acids and can explain its liquid state on storage at room temperature. Acid values of 6.10 mg KOH/g coconut oil, 9.40 mg KOH/g avocado oil and 6.50 mg KOH/g carrot oil indicated that the oils are acceptable for industrial purposes. The % FFA values obtained as 3.10%, 4.70% and 3.30% for coconut, avocado and carrot oils respectively indicates the suitability of the oils for consumption. The FTIR scan analysis showed the various compounds present in the oils and by indication presented that coconut oil have dominant properties over that of carrot oil and should not be used as base oil for its extraction. Carboxylic acid (effective in providing antioxidant and anti-aging protection as well as improving moisture retention) and aromatic groups were found present as well as esters (excellent hydrating and softening agents). These compounds are found in all vegetable oils thereby validating their quality and explain the excellent properties of carrier oils and why they are used in conjunction with essential oils for aromatherapy purposes as well as for human consumption.

Problem statement: Resistance to third generation cephalosporins due to acquisition and expression of Extended Spectrum β-Lactamase (ESBL) among Gram-negative bacteria is on the increase. Infections involving extended spectrum beta lactamase bacteria are associated with significant morbidity and mortality. Therefore, infections due to ESBL isolates continue to pose a serious challenge to infection management worldwide. Since screening for ESBL is not a common practice in hospitals in Enugu state, this study was undertaken to characterize ESBL genes in K. pneumoniae strains from intensive care unit of the University of Nigeria Teaching Hospital (UNTH) Enugu. Approach: Over a period of 29 months, 57 patients out of 140 receiving treatment in the intensive care unit of the University of Nigeria Teaching Hospitals Enugu were found to be infected with extended-spectrum β-lactamase-producing strains of K. pneumoniae. Species identification of K. pneumoniae strains was performed by Standard Microbiology methods and reconfirmed by MALDI-TOF technology. Phenotypic characterization of Extended Spectrum Beta Lactamase (ESBL) was determined by double disc synergy test and presence of ESBL genes was determined by specific PCR. Results: All ESBL producers were positive in a PCR for bla CTX-M-1 cluster and on sequencing, bla CTX-M-15 were found to be present. Genotypic characterization of extended spectrum beta-lactamase producing K. pneumoniae showed that all isolates carried CTX-M-15and SHV genes, 41(71.9%) carried aac (6')-Ib-cr and bla OXA-1, 19(33%) carried bla TEM. ISEcp1 was found upstream and ORF 477 downstream of bla CTX-M. in all strains. Random amplified polymorphic DNA analysis grouped the strains into two clonal groups-A and B and majority of the strains belong to clonal group A (n = 42). Conclusion: This study shows for the first time the presence of ESBL genes in K. pneumoniae from the ICU of UNTH Enugu and therefore strongly butresses the need for regular screening for ESBLproducing bacteria in clinical specimen in ICU and other wards in Nigerian hospitals.

The search for the healing properties of plants is an ancient idea that has remained even till date. In this work, the antibacterial activity of leaf extracts of Corchorus olitorius, Pterocarpus santaliniodes, Pentaclethra macrophylla and Azadirachta indica was tested against resistant strains of Staphylococcus aureus, Escherichia coli, Klebsiella species and Streptococcus species using agar well diffusion method. The following concentrations of 100, 50, 25 and 12.5 mg/ml of aqueous, ethanol and methanol leaf extracts were used against the test organisms. Results of this study reveal that all the leaf extracts had antibacterial activity against the test organisms at various concentrations (in particular: at 100 and 50 mg/ml) but the aqueous leaf extracts had higher inhibitory effect for all of them. However, little inhibitory effect was observed with the methanol and ethanol leaf extracts. Our findings justify the therapeutic use of these plants by traditional healers in most part of Nigeria for the treatment of infections caused by these bacteria. Medicinal plants have unlimited possibilities to produce putative compounds for the development of novel drugs to curtail the upward trend in bacterial resistance, thus the need for sustained research towards this objective.

Microbial fuel cells (MFCs) are typically designed as a two-chamber system with the bacteria in the anode chamber separated from the cathode chamber by a polymeric proton exchange membrane (PEM). Most MFCs use aqueous cathodes where water is exposed to air to provide dissolved oxygen to electrode. To increase energy output and reduce the cost of Microbial Fuel Cells, charcoal electrode (locally prepared) at the composition of 2:1 charcoal/cement ratio was used. Ammonia fertilizer plant liquid effluent was used as the substrate, while the bacteria present in the wastewater were used as the biocatalyst. The cells were operated at room temperature with pH of 6.68. The anode and cathode chambers were kept under anaerobic and aerobic conditions respectively. The cell 3 setup with electrode area of 3.63×10-3 m 2 was observed to have the highest power density of 134.5455mW/m 2 and current density of 181.8182mA/m 2 while cell 4 setup with electrode area of 3.63×10-3 m 2 was observed to have the least power density of 108.9807mW/m 2 and current density of 126.7218mA/m 2 .

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