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Item ENVIRONMENTAL HYGIENE AND MICROBIOLOGICAL ASSESSMENT OF FOOD SERVICE ESTABLISHMENTS IN SELECTED BOARDING HIGH SCHOOLS IN IBADAN, NIGERIA(2023-07) ADEBAYO, K.ASchools’ Food Service Establishments (FSEs) have been incriminated in numerous foodborne diseases outbreaks globally and have been linked to the environment and food handling procedures in the establishments. Despite this, FSEs in Nigerian boarding schools have been poorly investigated. In order to provide baseline data for infection control, this study was designed to assess environmental hygiene and food handlers’ Knowledge, Attitude and Practices (KAP) and investigate food-related microbial contamination from selected boarding schools’ FSEs in Ibadan, Nigeria.Observational checklist and interviewer-administered questionnaire were used to evaluate environmental hygiene parameters, food handlers’ KAP in four schools’ FSEs out of forty-three schools by inclusion criteria and balloting. Swabs from Food Contact Surfaces (FCS): utensils and surfaces; 20 food handlers’ hands and samples of Ready to-Eat (RTE) foods were examined for Aerobic Plate Count (APC), Total Coliform (TC), Faecal Coliform (FC) and selected important foodborne pathogens counts using standard methods. Isolated bacteria were characterised phenotypically and subjected to 16S rRNA sequencing. Antibiotic susceptibility testing was determined using disc diffusion and E-strip techniques based on CLSI and EUCAST standards, respectively. Data were analysed using descriptive statistics and ANOVA at α0.05. Schools FSEs’ compliance mean scores for environmental hygiene parameters were 82.2, 56.8, 52.7 and 65.6% for toilets, dining areas, kitchens and observed food handlers at work, respectively. The food handlers had good knowledge (61.9%), positive attitude (81.4%) to ensure food safety, but poor hygiene practices (52.6%) which differed significantly among schools (p=0.012, χ2=10.15). Major unsanitary practices observed were: use of basins and buckets for dish washing, uncovered solid waste receptacles, non-availability of sanitising agents and inadequate handwashing. Mean logCFU/cm2 of APC for counter tops, chopping boards, grinders, trays and knives were 5.59±1.56, 4.38±2.62, 4.01±0.77, 2.47±2.23 and 2.38±1.75, respectively. Food handlers’ hands’ mean logCFU/cm2 of APC, TC, FC, Staphylococcus and Bacillus species were 3.10±1.78, 2.62±1.23, 2.80±1.74, 1.94±1.04 and 1.97±1.39, respectively. Seventy-eight percent of RTE foods conformed to acceptable limit of < 4logCFU/g for APC. The distribution of bacteria from schools FSEs were 62.0% (FCS), 19.0% (food handlers’ hands) and 19.0% (RTE foods). The identified food-related bacteria were Alcaligenes faecalis, Achromobacter xylosoxidans, Bacillus cereus, Ochrobactrum anthropi,viiiProteus mirabilis, Serratia marcescens, Staphylococcus saprophyticus and Bordetella species. Alcaligenes faecalis resistance (%) to cefixime, cefuroxime, ceftazidime, gentamicin, augmentin, nitrofurantoin, ofloxacin and ciprofloxacin were 76.2, 71.4, 66.7, 61.9, 57.1, 42.9, 4.8 and 4.8, while for Bacillus cereus, they were 85.7,100.0, 57.1, 85.7, 28.6, 57.1, 0.0 and 0.0, respectively. The minimum inhibitory concentration of colistin for Alcaligenes faecalis ranged from 1.5 µg/mL to >256 µg/mL which was highly significant (F=9.194, p<0.05) compared to other antibiotics. Two Bacillus cereuswere resistant to imipenem, 81.0% were multi-antibiotic resistant, while none of the identified bacteria showed resistance to piperacillin/tazobactam.Food contact surfaces and food handlers’ hands were grossly contaminated. The presence of colistin-resistant Alcaligenes faecalis and resistance of Bacillus cereus to imipenem in boarding schools’ food service establishments is a serious public health concern. These findings will be useful in policy formulation and the development of food safety guidelines in boarding schools.Item INDIGENOUS BACTERIAL DIVERSITIES IN TWO AGRICULTURAL SOILS AS INFLUENCED BY CHEMICAL AND ORGANIC HERBICIDES(2024-06) NWOKOCHA, A.GAgricultural soils as habitats for beneficial soil bacteria are usually invaded by weeds, an occurrence which has detrimental effects on crops. Chemical herbicides mostly employed for weed control adversely affect soil bacteria. Previous studies have reported chemical herbicides’ effects on soil bacterial diversity suppressing microbial growth, however, information on soil types, and organic herbicides that could be an alternative is limited. Therefore, this study was designed to investigate the effects of chemical and organic herbicides on bacterial diversity in Alfisol and Inceptisol. Soils (Alfisol and Inceptisol) were collected from research farms at University of Ibadan, Institute of Agricultural Research and Training, National Horticultural Research Institute, and International Institute of Tropical Agriculture. In a screen house experiment using a factorial arrangement in a completely randomised design, Atrazine and S-Metolachlor (AS-M), Isopropyl Amine (IA), and Acetic Acid (AA) herbicides were applied as pre-, post- and organic herbicides, respectively on the soils. In the field experiments, AS-M, IA and AA herbicides were also applied to the Alfisol and Inceptisol. All herbicide-treated soils were sampled at 4 and 8 weeks and bulked to determine physico-chemical parameters and herbicides persistency of the treated and untreated soils using standard methods. The effect on bacterial diversity in herbicide treated Alfisol and Inceptisol were determined by DNA extraction from the soil samples using 16S rRNA amplicons sequenced on illumina miseq. Data were analysed using descriptive statistics, QIIME 2, and ANOVA at α0.05. Untreated Alfisol pH (6.20±0.12), organic carbon (3.90±0.04g/kg) and clay content (112.20±0.55g/kg) were significantly higher than Inceptisol pH (5.50±0.15), organic carbon (1.90±0.01g/kg) and clay content (103.90±0.81g/kg). At week 4, pH and organic carbon were significantly higher in Alfisol (6.30±0.21: 0.40±0.06g/kg) than Inceptisol (5.40±0.21; 0.10±0.06g/kg). Herbicides’ persistency was higher in Alfisol than Inceptisol. Intermediate products (acetamide) in AA-treated soil (Alfisol: 30.2%; Inceptisol: 25.0%) < 2-amino-3-4- dihydro-4-4-dimethyl-6-pyrimidinone (Alfisol: 48.7%; Inceptisol: 35.3%) in IA < atrazine (Alfisol: 50.9%; Inceptisol: 37.1%) in AS-M at week 4, with a similar trend Alfisol: 22.1%, Inceptisol: 19.2%; Alfisol: 42.6%, Inceptisol: 33.2%; Alfisol: 43.9%, Inceptisol: 35.1% at week 8. Alfisol had significantly higher bacteria taxa of 79% than 21% in Inceptisol. Methylomicrobium, Saccharopolyspora, Domibacillus, Blatococcus, Fuctibacillus, Limnobacter, Sneathiella, Nocardiopsis, Aquisphaera, and Stenotrophomonas were found in Alfisol and Inceptisol. However, Limnobacter and Methylomicrobium; Sneathiella and Nocardiopsis; Aquisphaera and Saccharopolyspora; were the bacterial genera that survived in AS-M, IA and AAtreated-soils, respectively. Significant effect in relative abundance of bacterial genera Chthoniobacter (Alfisol: 0.5%, 0.4%, 0.3%, 0.6%: Inceptisol: 0.3%, 0.2%, 0.3%, 0.5%) and Pedosphaera (Alfisol: 0.6%, 0.6%, 0.5%, 0.9%, Inceptisol: 0.7%, 0.5%, 0.5%, 0.9%) were observed at week 4, Chthoniobacter (Alfisol: 0.5%, 0.4%, 0.4%, 0.6%: Inceptisol: 0.3%, 0.3%, 0.4%, 0.5%) and Pedosphaera (Alfisol: 0.6%, 0.8%, 0.5%, 0.9%, Inceptisol: 0.3%, 1.2%, 0.9%, 1.3%) at week 8 in untreated and soil treated with AS-M, IA and AA, respectively. Alpha and beta diversity indicated significant differences in the relative abundance of bacteria between Alfisol and Inceptisol. The relative abundance of bacteria diversity in Alfisol and Inceptisol were reduced by chemicals but increased by organic herbicidesItem A VECTOR MATRIX APPROACH OF COUNTING CYCLIC QUOTIENTS OF SOME ABELIAN P-GROUPS(2009) Enioluwafe, M.We determine in this paper, the precise number of cyclic quotients of Abelian p-groups of exponent p i and rank r > 1, i = 1, 2, . . . , n for all natural numbers nItem The Subgroups for the Finite p-Group of the Structure D24 x C25(2022) Adebisi, S.A.; Ogiugo, M.; EniOluwafe, M.Every finite p-group is nilpotent. The nilpotence property is an hereditary one. Thus, every finite p-group possesses certain remarkable characteristics. Efforts are carefully being intensified to calculate, in this paper, the explicit formulae for the number of distinct fuzzy subgroups of the cartesian product of the dihedral group of order with a cyclic group of order of an m power of two for, which .Item The Computation for the Fuzzy Subgroups of the Algebraic Structure D2> x C-z(2022) Adebisi, S.A.; Ogiugo, M.; EniOluwafe, M.Any finite uilpoleut group can be uniquely written as a direct product of /<- groups In this paper, an attempt for the compulation of Dv.i x CTi was made. This happens to be the eomputatioii of the number of distinct fuzzy subgroups of the cartesian product of the dihedral group of order 24 with a cyclic group of order sixteenItem The Number of Chains of Subgroups in the Lattice of Subgroups of Group(2022) Ogiugo, M.; Seghal, A.; Adebisi S.A.; EniOluwafe, M.In this paper, we established the number of chains of subgroups in the subgroup lattice of the Cartesian product of the alternating group and cyclic group using computational technique induced by the set of representatives of isomorphism classes of subgroupsItem The Fuzzy Subgroups for the Nilpotent (P-Group) of (D23 × C2m) for M ≥ 3(2022) Adebisi, S.A.; Ogiugo, M.; EniOluwafe, M.A group is nilpotent if it has a normal series of a finite length n. By this notion, every finite p-group is nilpotent. The nilpotence property is an hereditary one. Thus, every finite p-group possesses certain remarkable characteristics. In this paper, the explicit formulae is given for the number of distinct fuzzy subgroups of the Cartesian product of the dihedral group of order 23 with a cyclic group of order of an m power of two for, which m ≥ 3.Item The Modular Nilpotent Group Mpn × Cp for p > 2(2021) Adebisi, S. A.; EniOluwafe, M.In this paper, the classification of finite p-groups is extended to the modular nilpotent group of the form Mpn × Cp in which, p is greater than 2Item The Number of Chains of Subgroups of the Group Zm ×Sn,n ≤ 5,m ≤ 3(2021) Ogiugo, M.; Adebisi, S.A.; EniOluwafe, M.The study of chains of subgroups in this paper describes the set of all chains of subgroups of G that end in G which is used to solve many computational problems in fuzzy group theory. It is also showed that a fuzzy subgroup is simply a chain of subgroups in the lattice of subgroups.Item The Abelian Groups of Large Order: Perspective from (Fuzzy) Subgroups of Finite p-Groups(Science Publishing Group, 2021) Adebisi, S.A.; Ogiugo, M.; EniOluwafe, M.In the recent past, results have shown that Nilpotent groups such as p-groups, have normal series of finite length. Any finite p-group has many normal subgroups and consequently, the phenomenon of large number of non-isomorphic subgroups of a given order. This makes it an ideal object for combinatorial and cohomological investigations. Cartesian product (otherwise known as the product set) plays vital roles in the course of synthesizing the abstract groups. Previous studies have determined the number of distinct fuzzy subgroups of various finite p-groups including those of square-free order. However, not much work has been done on the fuzzy subgroup classification for the nilpotent groups formed from the Cartesian products of p-groups through their computations. Here, part of our intention is therefore trying to make some designs so as to classify the nilpotent groups formed from the Cartesian products of p-groups through their computations. The Cartesian products of p-groups were taken to obtain nilpotent groups. Results up to two dimensions are now obtainable. In this paper, the fuzzy subgroups of the nilpotent product of two abelian subgroups of orders 2n and 128. The integers n ≥ 7 have been successfully considered and the derivation for the explicit formulae for its number distinct fuzzy subgroups were calculated. Some methods were once being used in counting the chains of fuzzy subgroups of an arbitrary finite p-group G. Here, the adoption of the famous Inclusion-Exclusion principle is very necessary and imperative so as to obtain a reasonable, and as much as possible accurate