Abstract: Background and Objective: Schiff bases as organic compounds have gained applications in different fields and recently as good inhibitors of mild steel corrosion, hence the evaluations of 2-(thiazol-2-ylamino)-2,3-dihydronaphthalene-1,4-dione (TADHN) for corrosion inhibition potentials. Materials and Methods: Perkin Elmer and Jeol-400 MHz spectrophotometers were used to acquire the spectral data of the compounds. The Hanna-H1991-300 conductivity meter and Johnson Matthey μeff balance were utilized for molar conductance plus μeff properties’ measurements. The C, H, N, S estimations were acquired on an Elementar Vario-EL-Cube analyzer. TADHN has been obtained in a 1:1 ratio from the condensation of 2-hydroxy-2,3-dihydro naphthalene-1,4-dione with thiazol-2-amine (TZ-2-A). Further reaction of TADHN with divalent salts in 2:1 stoichiometric faction gave the corresponding complexes. Results: Acquired spectral data plus the magnetometric evaluation conformed to the keto-imine tautomeric assemblage of TADHN, octahedral, tetrahedral and square planar structural assemblages for the Mn2+ and Fe2+, Co2+, Ni2+ and Zn2+, plus Cu2+ complexes separately. The molar conductance values acquired for M2+ complexes were too low to accommodate dissociation within each complex unit validating their ionic free status. All the M2+ complexes apprised for magnetic behaviours remained paramagnetic in the validation of the suggested structural assemblages, except the Zn2+ complex which was practically diamagnetic. Also, Density Functional Theory (DFT) technique substantiated the optimized structure of TADHN. Conclusion: The corrosion inhibition experimentations validated that the studied inhibitor exhibited 92% inhibition efficiency at a concentration of 500 ppm and 300K. Hence, this study concludes that the corrosion inhibition effect was dependent on the concentration of the inhibitor plus the solution temperature. PubDate: 14 May, 2022
Abstract: Background and Objective: Seropositivity rates of rubella virus infection among pregnant women vary worldwide. Yemen is among the developing countries the rubella disease is still present. This study was designed to estimate the seropositivity rate of rubella infection and risk factors associated among pregnant women attending antenatal care clinics in Mukalla city, Hadhramaut, Yemen. Materials and Methods: This was a cross-sectional study performed on a total of 190 pregnant women and the serum samples were collected and screened using the enzyme-linked immunosorbent assay (ELISA) anti-rubella virus IgM and IgG test. Qualitative demographic and reproductive data were collected using a standardized questionnaire. Results: One hundred-ninety pregnant women tested for rubella antibodies, 136 (71.6%), were positive for anti-rubella IgG, while 17 (8.9%) was positive for IgM. Higher seropositivity rates were found in the age group of the age groups 15-30 years with significantly dependent (COR = 0.749, 95% CI = 0.113-0.557, p = 0.001) and the moderate level income (COR = 0.761, 95% CI = 0.075-0.760, p = 0.015). Anti-IgM positive rubella infection had a significant relationship with the pregnant women miscarriage (COR = 0.925, 95% CI = 0.020-0.283, p = 0.00) and the risk of contracting rubella virus infection was found to increase with history of live births with a statistical significance (COR = 1.942, 95% CI = 1.020-3.695, p = 0.043). Conclusion: Seropositivity rates of a rubella infection are high in Mukalla city, Hadhramaut and are significantly associated with an increase in age and being income level. The risk of contracting rubella infection was found to increase with gestational age and associated with miscarriage. Screening of rubella and immunization of women at risk is highly recommended in this area with a high non-immune rate against the rubella virus. PubDate: 14 May, 2022
Abstract: Background and Objective: Population growth and high demand for wood and wood products in Nigeria is on the increase and subsequently put undue pressure on the forest estates, therefore this research was centred on the identification and status of commonly exploited indigenous timber species by saw millers in Odigbo Local Government Area, Ondo State, Nigeria. Materials and Methods: One hundred and twenty well-structured questionnaires were administered in ten different sawmills to obtain information from the respondents using the purposive sampling method. A total of 120 respondents, comprising of 80 males and 40 females with an average age of 45 years were interviewed. About 20 indigenous timber species belonging to 13 families and 16 genera were identified. Results: The result reveals that Meliaceae had the highest frequency of 5 (18.5%), followed by Fabaceae with a frequency of 4 (14.8%). It was observed that vulnerable (11), endangered (10), un-evaluated (4), critically endangered (1) and least concern (1), respectively were trees species from the families of (Caesalpinioideae, Meliaceae, Rubiaceae, Combretaceae, Euphorbiaceae and Ochnaceae), Bombacaceae, Fabaceae, Bignoniaceae, Malvaceae, Leguminosae and Sterculiaceae), (Apocynaceae, Moraceae and Fabaceae), (Santalaceae) and (Boraginaceae), respectively. Conclusion: The rate at which trees are exploited in this area revealed a tremendous decline in the number of indigenous timber species in the study area and this necessitates an urgent need for proper strategies and policy enforcement to minimize the rate at which indigenous timber species are being exploited in the area to ensure sustainability. PubDate: 14 May, 2022
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