Origin of light hydrocarbons in recent carbonate oolites in relation to the problem of petroleum genesis in carbonate rocks

Imperial Users onl

Perceived Impact of Industrial Actions on the Academic Performance of Students in Tertiary Institutions in Delta State Nigeria

The study investigated the perceived impact of industrial actions on the academic performance of students in tertiary institutions in Delta State, Nigeria. Three research questions were raised and answered in the study. Two null hypotheses were formulated and tested at a .05 level of significance. A descriptive survey research design was used in the study. Two hundred seventeen students of tertiary institutions in Delta State comprised the sample of the study. A structured questionnaire titled ‘Impact of Industrial Action on Students’ Academic Performance Questionnaire’ (IIASAPQ)’ was used for data collection. Mean and standard deviation, as well as t-test statistics, were used to answer the research questions. The formulated null hypotheses were tested at a .05 level of significance using t-test statistics. The findings revealed that instability in the policies of the government both at the central and state levels, poor welfare and remuneration package of the staff of the various unions, among others, are causes of industrial actions of unions of Nigeria tertiary institutions, and the difference in the mean ratings on the causes of industrial actions of unions of Nigeria tertiary institutions is not significant based on gender. Additionally, lack of interest in school among students, which leads to poor academic performance, reduced and low grades, and poor study habits among students to a great extent are the impact of industrial actions of various unions on the academic performance of students in Nigeria tertiary institutions, and, the difference in the mean ratings on the extent industrial actions impacts academic performance of students in Nigeria tertiary institutions is not significant based on gender. Based on the findings, the study recommended, among others, that the federal government should ensure that there is a smooth and regular dialogue with various unions of tertiary institutions so as to avoid incessant industrial actions. The unions of various tertiary institutions should understand the impact of their industrial action on the academic performance of the students, therefore, seek alternative means of dispute and conflict resolution with the federal government instead of resorting to industrial actions

Fate, Distribution and Sources of Polycyclic Aromatic Hydrocarbons (PAHs) in Contaminated Soils in Parts of Calabar Metropolis, South Eastern Nigeria

The paper is aimed at the investigation of polycyclic aromatic hydrocarbons (PAHs) in contaminated soils collected at depths of 15 to 100cm from two spilled sites in the vicinity of a leaking pipeline (Calabar, Nigeria). The soils were prepared in the laboratory using standard procedure and were analyzed for sixteen priority PAHs using Gas Chromatography – Mass Spectrophotometer (GC - MS).The concentration of total PAHs (TPAHs) in the contaminated soils ranged from 4.28 to 29.77mg/Kg and decreased with depth. These levels are higher than values obtained from rural and semi urban soils but lower than values obtained from soils in the vicinity of some petroleum handling facilities in part of the study area. Generally the soils were relatively enriched with medium- and lower-molecular-weight PAHs. Phenanthrene/Anthracene, Fluoranthene/Pyrene, Fluorantine/Fluorantine+Pyrene and Benzo(A)Anthracene/Chrysene ratios and the relative abundance of PAHs according to the number of rings were used to access the sources of PAHs. In addition, the main mechanism of PAHs transport in the study area was proposed.Keywords: Fate; Distribution; Sources; PAHs; Soils; contaminated soils; Calaba

Analyses of Use of Improved Beekeeping Equipment among Agricultural Development Programme Registered Bee Farmers in Imo State, Nigeria

The study examined improved beekeeping in Imo State, Nigeria. A sample of 30 registered bee farmers participated in the study. Data were elicited from the farmers using structured questionnaire and analysed using percentages and means. Results showed that the major sources of information on modern bee keeping equipment were farmers’ association (96%), extension agents (76%) and friends/relatives (70%). Available bee products in the area were honey (97%), bee wax (83%), bee venom (70%) and propolis (63%). Improved beekeeping equipment used in the area were foot wears (100%), gloves (100%), smokers (93%), bee veil (96%) and bee suits (87%). Constraints to improved beekeeping in the area include; lack of favourable agricultural policies (87%), lack of standard market for the products (77%), inadequate training and information on beekeeping (67%) and high cost of equipment (70%). The study therefore recommends the need for efforts aimed at promoting modern bee farming in the area, especially targeted at younger and educated farmers

M/M/1 Multiple Vacation Queueing Systems with Differentiated Vacations

We consider a multiple vacation queueing system in which a vacation following a busy period has a different distribution from a vacation that is taken without serving at least one customer. For ease of analysis it is assumed that the service times are exponentially distributed and the two vacation types are also exponentially distributed but with different means. The steady-state solution is obtained

GENDER AND LEVELS OF ATTAINMENT OF SCIENTIFIC LITERACY AMONG SCIENCE STUDENTS UNDER CONSTRUCTIVIST INSTRUCTIONAL MODEL

The study investigated levels of attainment of scientific literacy by junior secondary (8th grade) male and female students. Quasi-experiment of non- equivalent control group design was used. A total of 162 students were selected by purposive sampling of four coeducational schools out of twenty three in Ohafia Local Government Area, Abia state, Nigeria. In each of the four schools, an intact class was randomly selected. These were randomly assigned, two to experimental and control groups. Research questions were answered using mean and standard deviations and the hypotheses tested using ANCOVA. TOSL instrument for data collection had parts A and B. Reliability Coefficient of part A was established using Spearman rank order correlation and B using Kuder-Richardson formula 20(K-R). The internal consistencies were 0.69 and 0.72. The findings showed that constructivist instruction enhanced students’ attainment of scientific literacy irrespective of their sexes. Based on the findings recommendations were made

Antioxidant and antimicrobial evaluation of the methanol leaf extract and fractions of dacryodes klaineana pierre (burseraceae)

ABSTRACT. Dacryodes klaineana is used in traditional medicine for the treatment of painful menstruation; tachycardia and cough. The study aims to evaluate the antioxidant and antimicrobial properties of the plant. The extract and fractions of D. klaineana were screened for their antioxidant effects using the 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and the total phenolic contents (TPC) assay methods. The antimicrobial activity of the plant was evaluated using the agar diffusion method against four different bacterialstrains (Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa) and two fungi strains (Aspergillus niger and Candida albicans). The crude methanol extract (MLE), hexane fraction (MLHF), ethyl acetate fraction (MLEF) and butanol fraction (MLBF) produced dose-dependent antioxidant activity using DPPH and FRAP assays. The antioxidant activity of MLEF was comparable to the standard drug, ascorbic acid. MLEF also gave the highest content of total phenol content with a percent gallic acid equivalent of 100.68 ± 1.17 mg GAE/g. The extract and fractions were active against the bacteria species, but inactive against the fungi species. The study demonstrated that the antioxidant and antimicrobial potentials of D. klaineana may offer a promising source of new antioxidants and antimicrobials in the ethnomedicinal management of diseases.                 KEY WORDS: Medicinal plant, FRAP, TPC, DPPH, Antioxidant, Dacryodes klaineana   Bull. Chem. Soc. Ethiop. 2022, 36(1), 85-94.                                                                   DOI: https://dx.doi.org/10.4314/bcse.v36i1.8                                                       &nbsp

Cosmic Ray Spectra in Nambu-Goldstone Dark Matter Models

We discuss the cosmic ray spectra in annihilating/decaying Nambu-Goldstone dark matter models. The recent observed positron/electron excesses at PAMELA and Fermi experiments are well fitted by the dark matter with a mass of 3TeV for the annihilating model, while with a mass of 6 TeV for the decaying model. We also show that the Nambu-Goldstone dark matter models predict a distinctive gamma-ray spectrum in a certain parameter space.Comment: 16 pages, 4 figure

Patterns of Soft Masses from General Semi-Direct Gauge Mediation

We give a general formulation of semi-direct gauge mediation of supersymmetry breaking where the messengers interact with the hidden sector only through a weakly gauged group. Using this general formulation, we provide an explicit proof that the MSSM gaugino masses are vanishing to leading order in the gauge couplings. On the other hand, the MSSM sfermion masses have, generically, a non-vanishing leading contribution. We discuss how such a mechanism can successfully be combined with other mediation schemes which give tachyonic sfermions, such as sequestered anomaly mediation and some direct gauge mediation models.Comment: 26 pages, 5 figures; v2: refs added; v3: minor corrections, clarifications added, mainly in section

Small steps towards Grand Unification and the electron/positron excesses in cosmic-ray experiments

We consider a small extension of the standard model by adding two Majorana fermions; those are adjoint representations of the SU(2)_L and SU(3)_c gauge groups of the standard model. In this extension, the gauge coupling unification at an energy scale higher than 10^{15} GeV is realized when the masses of the triplet and the octet fermions are smaller than 10^4 GeV and 10^{12} GeV, respectively. We also show that an appropriate symmetry ensures a long lifetime of the neutral component of the triplet fermion whose thermal relic density naturally explains the observed dark matter density. The electron/positron excesses observed in recent cosmic-ray experiments can be also explained by the decay of the triplet fermion.Comment: 11 pages, 5 figure