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AtzABC Catabolic Gene Probe from Novel Atrazine-Degrading Rhodococcus Strain Isolated from a Nigerian Agricultural Soil

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Advances in Microbiology 2012年第4期2卷 593-597页

作者： Ahmed Faruk Umar Fatimah Tahir Michael J. Larkin Olubukola Mojisola Oyawoye Balarabe Lawal Musa mohammed bello yerima Ediga Bede Agbo Biological Sciences Programme Abubakar Tafawa Balewa University Bauchi Nigeria Microbiology Department Usmanu Dan Fodio University Sokoto Nigeria Queens University Environmental and Genomic Research (QUESTOR) Center Queens University of Belfast Belfast Northern Ireland UK

A batch enrichment technique was used to isolate atrazine-degrading Rhodococcus sp strain from an agricultural land with history of atrazine application in Bauchi state, Northeastern Nigeria. The strain was identified on the basis of physiological, biochemical and 16S r RNA gene sequencing. Growth studies and HPLC analysis showed that the strain has potential of atrazine degradation. An investigation into the catabolic genes Atz ABC, which transform atrazine to cyanuric acid, confirms the chromosomal DNA of strain to harbor BC genes, as compared with the positive control, Rhodococcus jostii RHA1. The strain does not possess the Atz A in all catabolic gene probe carried out. The isolation and characterization of the Rhodococcus sp strain showed that catabolic genes may have evolved from a single origin with widespread global distribution, with possible potential in atrazine bioremediation.

关键词： Enrichment Catabolic Genes Bioremediation Atrazine

Classification, Tectonic Setting, and Mineralization Potential of Ayetoro and Sasaro Syenitic Plutons in Igarra Schist Belt, Southwestern Nigeria

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International Journal of Geosciences 2024年第6期15卷 493-510页

作者： mohammed Olatoye Adepoju Yinusa Ayodele Asiwaju-bello Department of Applied Geology Federal University of Technology Akure Nigeria

Petrographic and geochemical studies of syenite-looking Ayetoro and Sasaro plutons within Igarra Schist Belt were carried out in order to classify them and determine their tectonic setting and mineralization potential. Petrographic study and geochemical classification revealed that while Ayetoro boss is microgranite constituting an aggregate of medium grained muscovite, quartz and biotite minerals, Sasaro stock is micromonzonite made up of medium grained albite, orthoclase, biotite, hornblende and pyroxene. Geotectonic setting showed the boss and stock are orogenic, probably derived from the same upper mantle magma as Igarra batholith that got contaminated by crustal materials responsible for their difference in lithology. Their mineralization potential showed that the massive Ayetoro microgranite with no appreciable trace-element contents cannot serve as host of any metallic deposit, and should be suitable for industrial applications. Whereas, the silicified, highly sheared Sasaro monzonite, with elevated level of some trace elements contents as Ag, Au and Cu, could harbor Ag-Au-Cu deposit.

关键词： ICP-MS Microgranite Micromonzonite Orogenic Ag-Au-Cu Deposit Igarra Schist Belt

Ethmoidal Polyposis, Adenoid Hypertrophy and Tympanic Membrane Perforation—A Case Report

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International Journal of Otolaryngology and Head & Neck Surgery 2024年第3期13卷 178-186页

作者： Ahmad Mahmud mohammed bello Fufore Abubakar Umar Hamisu Abdullahi Thomas Musa Samdi Auwal Adamu Onyekwere George B. Nwaorgu Department of Otorhinolaryngology Modibbo Adama University/Modibbo Adama University Teaching Hospital Yola Nigeria Department of Otorhinolaryngology Bayero University/Aminu Kano Teaching Hospital Kano Nigeria National Ear Care Centre (NECC) Kaduna Nigeria Department of ENT Abubakar Tafawa Balewa Teaching Hospital Bauchi Nigeria Department of ENT Federal University of Health Sciences Azare Bauchi Nigeria Department of Otorhinolaryngology University College Hospital Ibadan/College of Medicine University of Ibadan Ibadan Nigeria

Background: Ethmoidal polyposis coexisting with adenoid enlargement and tympanic membrane perforation is a rare condition in otolaryngological practice. Evidences have shown that antrochoanal polyp often times coexists with adenoid enlargement especially in the young which was in sharp contrast to ethmoidal polyposis occurring in the presence of adenoid enlargement. Moreover, the hidden location of nasopharynx housing the adenoids, coupled with the masking effect of bilateral sinonasal polyps, leads to inadvertent misdiagnosis of this complex pathology with subsequent difficulty in providing effective management. Case Presentation: A 24 year-old lady presented with recurrent bilateral nasal obstruction that became persistent associated with nasal discharge and anosmia. She also had recurrent right otorrhoea with associated hearing loss. Diagnostic rigid nasal endoscopy revealed mucoid discharge with bilateral polypoid masses filling both nasal cavities. Otoendoscopic finding revealed a small (about 5%) central tympanic membrane perforation. A clinical assessment of chronic rhinosinusitis with nasal polyposis complicated by chronic suppurative otitis media (CSOM) was made. A non-contrast CT scan of the paranasal sinuses showed isodense lesions in the nasal cavities, all paranasal sinuses and the entire nasopharynx. She had endoscopic sinus surgery and a nasopharyngeal clearance biopsy. The nasal, paranasal and nasopharyngeal masses had histologic confirmation of inflammatory nasal polyps and lymphoid (adenoid) hyperplasia respectively. Her condition improved remarkably with subsequent medical treatment. She was followed up for 8 months and no recurrence was observed. Conclusion: Sinonasal polyposis can coexist with adenoid hypertrophy and middle ear disease as a single pathological condition. Hence, a high index of suspicion and thorough evaluation become necessary for making timely diagnoses and instituting effective management.

关键词： Sino-Nasal Polyps Adenoid Enlargement Rhinosinusitis Otitis Media Endoscopic Sinus Surgery

Quartz dissolution in a single phase-high pH Berea sandstone via alkaline injection

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Energy Geoscience 2021年第3期2卷 181-188页

作者： Abdullah Musa Ali mohammed yerima Kwaya Abubakar Mijinyawa Department of Geology Bayero University Kano(BUK)KanoNigeria

A common assertion is that alkaline solution aids oil mobilization by generating in situ soap,or by lowering interfacial tension(IFT)to ultra-low values in synergy with *** study takes a different approach that involves the alkaline dissolution of detrital quartz grains of sandstone reservoirs to create pathways for oil migration and *** dissolution via alkaline injection will result in changes in permeability and *** study performed high-pH core flooding on Berea sandstones using core displacement *** molybdate spectrophotometry was applied to measure the amount of dissolved *** and confining pressure variations were also *** molar concentration of NaOH varied at 0.5 M and 1.0 *** results show higher initial silica dissolution for 0.5 M NaOH(˃200mg/L)compared to 1.0 M NaOH(20 mg/L),which can be attributed to the presence of pre-existing dissolved silica and precipitates in the system prior to the first injection ***,a steady quartz dissolution rate of 0.4 mg/L/hr for 20 h was only achieved at 1.0 ***,an abrupt drop in quartz dissolution to below 0 mg/L was recorded for 0.5 M NaOH after 3 h of *** higher molar concentration of injected alkaline solution,both confining and inlet pressures increased from 8 and 5 bars to 12 and 11 bars as a result of the increased secondary phase of(hydr)oxides or precipitates in the ***,it can be inferred that the effect of alkaline solution on quartz dissolution is strongly dependent on molar concentration.

关键词： Alkaline injection Core flooding Dissolved silica Quartz Petroleum recovery

Characterization of cobalt ferrite-supported activated carbon for removal of chromium and lead ions from tannery wastewater via adsorption equilibrium

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Water Science and Engineering 2020年第3期13卷 202-213页

作者： Muibat Diekola Yahya Kehinde Shola Obayomi mohammed bello Abdulkadir Yahaya Ahmed Iyaka Adeola Grace Olugbenga Department of Chemical Engineering Federal University of TechnologyMinnaP.M.B.65Nigeria Department of Chemical Engineering Landmark UniversityOmu-AranP.M.B.1001Nigeria Department of Chemistry Federal University of TechnologyMinnaP.M.B.65Nigeria

In this experiment,cobalt ferrite-supported activated carbon(CF-AC)was developed and characterized via the wet impregnation method for the removal of Cr and Pb(II)ions from tannery *** adsorption was carried out to evaluate the effect of experimental operating conditions(pH of solution,contact time,adsorbent dose,and temperature),and the removal efficiencies of Cr and Pb(II)ions by the developed adsorbents were calculated and recorded for all experimental *** variables were estimated and reported as removal efficiencies of 98.2%for Cr and 96.4%for Pb(II)ions at the optimal conditions of 5,0.8 g,80 min,and 333 K for pH,adsorbent dose,contact time,and temperature,*** equilibrium for the sorption of Cr and Pb(II)ions was studied using four widely used isotherm models(the Langmuir,Freundlich,Dubinin-Radushkevich,and Temkin isotherm models).It was found that the Freundlich isotherm model fit better with the coefficient of determination(R2)of 0.9484 and a small sum of square error of *** maximum adsorption capacities(Qm)of Pb(II)and Cr adsorbed onto CF-AC were determined to be 6.27 and 23.6 mg/g,*** adsorption process conformed well to pseudo-second order kinetics as revealed by the high R2 values obtained for both *** thermodynamic parameters showed that adsorption of Cr and Pb(II)ions onto CF-AC was spontaneous,feasible,and endothermic under the studied *** mean adsorption energy(E)values revealed that the adsorption mechanism of Cr and Pb(II)by CF-AC is physical in *** results of the study showed that adsorbent developed from CF-AC can be efficiently used as an environmentally friendly alternative adsorbent,for removal of Cr and Pb(II)ions in tannery wastewater.

关键词： Almond husk Cobalt ferrite Equilibrium study Heavy metals Adsorption Removal efficiency

Geothermal Gradient and Heat Flow in the Nigeria Sector of the Chad Basin, Nigeria

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Computational Water, Energy, and Environmental Engineering 2016年第2期5卷 70-78页

作者： mohammed yerima Kwaya Ewa Kurowska Abdullahi Suleiman Arabi Department of Geology Usmanu Danfodiyo University Sokoto Nigeria Department of Fundamental Geology University of Silesia Katowice Poland Center for Energy Research and Training Ahmadu Bello University Zaria Nigeria

Information on geothermal gradient and heat flow within the subsurface is critical in the quest for geothermal energy exploration. In a bid to ascertain the thermal potential of Nigeria sector of the Chad Basin for energy generation, subsurface temperature information from 19 oil wells, 24 water boreholes drilled to depths beyond 100 metres and atmospheric temperature from the Chad basin were utilized in calculating geothermal gradient of the area. Selected ditch cuttings from the wells were subjected to thermal conductivity test using Thermal Conductivity Scanner (TCS) at the Polish Geological Institute Laboratory in Warsaw. The terrestrial heat flow was calculated according to the Fourier’s law as a simple product of the geothermal gradient and the mean thermal conductivity. Results obtained indicated geothermal gradient range of 2.81 °C/100 m to 5.88 °C/100 m with an average of 3.71 °C/100 m. The thermal conductivity values from the different representative samples range from 0.58 W/m*K to 4.207 W/m*K with an average of 1.626 W/m*K. The work presented a heat flow value ranging from 45 mW/m2 to about 90 mW/m2 in the Nigerian sector of the Chad Basin.

关键词： Geothermal Gradient Heat Flow Chad Basin Thermal Conductivity

Yield and Yield Components of Bread Wheat as Influenced by Water Stress, Sowing Date and Cultivar in Sokoto, Sudan Savannah, Nigeria

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American Journal of Plant Sciences 2013年第12期4卷 122-130页

作者： mohammed bello Sokoto Agit Singh Department of Crop Science Faculty of Agriculture Usmanu Danfodiyo University Sokoto Nigeria School of Biosciences Faculty of Science The University of Nottingham Malaysia Campus Jalan Broga Semenyih Selangor Malaysia

Field experiments were conducted during 2009/10 and 2010/2011 dry seasons at the Fadama Teaching and Research Farm of the Usmanu Danfodiyo University, Sokoto, in the Sudan Savanna ecological zone of Nigeria (latitude 13°01'N;longitude 5°15'E, altitude of 350 m above sea level) to study the effect of water stress, sowing date and cultivar on yield and yield components of wheat (Triticum aestivum L.). The treatments consisted of factorial combination of water stress at three critical growth stages which was imposed by withholding water at tillering, flowering, grain filling and control (no stress), four sowing dates (21st November, 5th December, 19th December and 2nd January) and two bread wheat cultivar (Star 11 TR 77173/SLM and Kuaz/Weaver), laid out in a split-plot design with three replications. Water stress and date of sowing were assigned to the main-plot, while variety was assigned to the sub-plots. Result revealed that water stress at tillering significantly reduced spike length and grains per spike. Whereas, water stress at flowering and grain filling significantly reduced 1000-grain weight, grain yield and harvest index. Results also indicated significant (P st November and 5th December and lowest at 19th December and 2nd January, therefore wheat should be sown in November or at least first week of December in this area and other area with similar climate. Variety had significant effect on spike per m-2, grain yield and harvest index. Water stress at flowering and grain filling should be avoided as they are the most critical growth stages in yield determination in wheat, because plants cannot recover, while delay in sowing resulted in reduction in yield and yield components. Star II TR 77173/SLM is therefore recommended for the area.

关键词： Yield Yield Components Bread Wheat Water Stress Sowing Date Cultivar Sudan Savanna

Clinical Isolates of Staphylococcus aureus Show Variation in β-Lactamase Production and Are More Susceptible to Antibiotics Conjugated with β-Lactamase Inhibitors

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Open Journal of Medical Microbiology 2016年第4期6卷 143-149页

作者： Uzal Umar Umar Ahmed Faruk Damoroem M. Tanko mohammed B. yerima Department for Biological Sciences Abubakar Tafawa Balewa University Bauchi Nigeria Department of Microbiology Federal University Dutse Dutse Nigeria

β-Lactam antibiotics are a cornerstone in the treatment of bacterial infections on account of its high therapeutic index and selective toxicity—they act by inhibiting the biosynthesis of peptidoglycan, a key component in bacterial cell wall. Ninety (90) clinical specimens obtained from the microbiology unit Specialist Hospital Bauchi were screened for S. aureus, positive isolates were examined for β-Lactamase expression by using two Penicillin G concentrations (5000 IU/ml and 25,000 IU/ml) in acidometric agar technique with phenol red as indicator, and the susceptibility pattern of the isolates to β-Lactam antibiotics was also determined. S. aureus prevalence of 31% (28/90) was obtained, of which 96% (27/28) of strains were β-Lactamase positive in the standard test, while 63% (17/27) were able to hydrolyze penicillin G concentration of 25,000 IU/ml (5X the concentration in the standard test), and a strain was found to be β-Lactamase negative. The resistance to five β-Lactams, ampicillin, cephalexin, amoxicillin, cloxacillin and flucloxaillin, were 100%, 96%, 89%, 74% and 56% respectively. When ampicillin and amoxicillin were conjugated to β-Lactamase inhibitors sulbactam and clavulanic acid respectively the resistance to ampicillin decreased to 21% and to amoxicillin to 15%. The antibiotic susceptibility profile revealed β-Lactamase elaboration to be the major mechanism of resistance to the β-Lactams. β-Lactam utilization as therapeutic option would thus require the search for sensitive irreversible β-Lactamase inhibitors for the β-Lactamase enzymes or agents to block the release of β-Lactamase by strains.

关键词： β-Lactamase Peptidoglycan Transpeptidation Haemolysis Resistance Antibiotics

以石墨烯为二维防护涂层的镍基合金（蒙乃尔）抗腐蚀性能的研究报告

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以石墨烯为二维防护涂层的镍基合金（蒙乃尔）抗腐蚀性能的研究报...

作者： HABIB mohammed-bello ABDULLAHI 华北电力大学(北京)

学位级别：硕士

一直以来,腐蚀一直被认为是金属浪费的主要原因,尤其是钢铁材料的浪费。许多机构都面临着与腐蚀相关的经济损失,同时,这些组织和机构及时采取了相应的腐蚀安全措施,以防止其不同的作业材料变质。在本论文中,主要着手于合成腐蚀防护膜,... 详细信息

一直以来,腐蚀一直被认为是金属浪费的主要原因,尤其是钢铁材料的浪费。许多机构都面临着与腐蚀相关的经济损失,同时,这些组织和机构及时采取了相应的腐蚀安全措施,以防止其不同的作业材料变质。在本论文中,主要着手于合成腐蚀防护膜,该膜基于掺杂有蒙脱尔合金吸附的酒石酸盐和草酸盐的组合的2D聚合物(石墨烯)涂层。与此同时,对防护膜在蒙乃尔合金上的耐腐蚀性能进行了研究,并将其与未涂层的蒙乃尔合金基底进行了比较。其次,采用循环伏安法和开路电势测量相结合的方法对它们进行了评估和研究。将石墨烯薄膜从PH值为8.0的0.10摩尔草酸酯溶液和PH值为7.0的0.10摩尔酒石酸酯溶液中沉积在蒙乃尔合金上,以在蒙乃尔合金上生成石墨烯-酒石酸酯和石墨烯-草酸酯薄膜。使用扫描电子显微镜的显微照片来确认聚合物是均质的、无缺陷、无裂纹的。此外,通过在环境空气,湿气和含氯化氢的环境中进行的详细实验室研究,对由高速空气燃料系统喷涂的石墨烯基涂料进行了研究,将暴露在有或没有氯化氢盐存在下于600摄氏度进行长达168小时。在蒙乃尔合金界面处形成包含石墨烯-酒石酸酯/石墨烯-草酸酯和石墨烯-草酸酯/聚吡咯-酒石酸酯的双层,并且该双层提供了更好的防腐蚀涂层。使用双层可观察到更高的击穿电位,在没有氯化氢的情况下,通过在高速空气燃料系统喷涂的石墨烯基涂料进行详细研究,以及就环境空气、湿气和氯化氢丰富的环境中进行了研究,我们发现,由于以下原因,所有涂料在所有环境中均具有极高的防护性在涂层表面形成保护氧化皮。

关键词：腐蚀石墨烯涂层合金蒙乃尔