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Geology of the Structurally Controlled Quartz Vein Gold Mineralization in the Dikko Area, Part of Zungeru—Minna—Birnin Gwari Schist Belt, NW Nigeria

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Journal of Geoscience and Environment Protection 2021年第7期9卷 180-191页

作者： abdullahi adamu mohammed adamu Usman mohammed Otorison Abdulganiu Danladi Abubakar Sadiq Applied Geology Department Abubakar Tafawa Balewa University Bauchi Nigeria Geology Department (Engineering Services) Federal Capital Development Authority (FCDA) Abuja Nigeria Hadejia Jama’are River Basin Development Authority Kano Nigeria

Dikko area, Niger State, North Central Nigeria falls within the Pan-African thermo-tectonic event which occurred in Nigeria as in other parts of West Africa with widespread effect on the mineralization of rejuvenated basement and geosynclinal trough deposits. The Pan-African Belt in Nigeria forms part of the Benin-Nigeria (Dahomeyan) shield which is regarded as the southern prolongation of the circumcratonic Pan-African belt of the West African Craton. Structurally controlled, gold-bearing quartz veins were measured and studied in the area from an extensive geological ground investigation. Field and petrographical studies indicate that the Neoproterozoic rocks constitute gneisses, amphibolite schist, amphibolites and migmatites. The amphibolites are intruded by pegmatites. The associated quartz veins are generally concordant with the main N-S regional structural trend. The lithological and structural studies carried out in these areas have demonstrated the relationship between structures and mineralization and/or lithology. The main characteristics of the gold mineralization in the area appear to indicate hydrothermal mineralization in connection with shear zones. This study allows us to predict that quartz veins in the amphibolite can be mined at a profit and a detailed geochemical and resource valuation needs to be carried out for the Au and associated Galena and Ag mineralization to fully exploit their economic potential.

关键词： Gold Mineralization Quartz Veins Pan-African Economic Potential Mined

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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

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First-Principles Investigation of Charge Transfer Mechanism of B-Doped 3C-SiC Semiconductor Material

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World Journal of Condensed Matter Physics 2024年第2期14卷 35-44页

作者： abdullahi Alkali Dauda Muhammad Yusuf Onimisi Adeyemi Joshua Owolabi Hameed Adeneyi Lawal Hassan Muhammad Gambo Bashir mohammed Aliyu Surajo Bala Muhammad Lamido Madugu Muhammad Abdurrahman Nainna Johnson Akinade Bamikole Physics Department Faculty of Science Air Force Institute of Technology Kaduna Nigeria Physics Department Faculty of Science Nigeria Defence Academy Kaduna Nigeria Physics Department Umaru Musa Yar&#8217adua University Batagarawa Nigeria Physics Department Faculty of Science Gombe State University Gombe Nigeria Physics Department Federal University of Lafia Lafia Nigeria

This study delves into the charge transfer mechanism of boron (B)-doped 3C-SiC through first-principles investigations. We explore the effects of B doping on the electronic properties of 3C-SiC, focusing on a 12.5% impurity concentration. Our comprehensive analysis encompasses structural properties, electronic band structures, and charge density distributions. The optimized lattice constant and band gap energy of 3C-SiC were found to be 4.373 Å and 1.36 eV respectively, which is in agreement with previous research (Bui, 2012;Muchiri et al., 2018). Our results show that B doping narrows the band gap, enhances electrical conductivity, and influences charge transfer interactions. The charge density analysis reveals substantial interactions between B dopants and surrounding carbon atoms. This work not only enhances our understanding of the material’s electronic properties, but also highlights the importance of charge density analysis for characterizing charge transfer mechanisms and their implications in the 3C-SiC semiconductors.

关键词： First-Principles Calculations DFT Boron (B)-Doped 3C-SiC Charge Transfer

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Research on LI-ION Battery Thermal Management in Low Temperature Zone Channel Management in Low Temperature Zone

Research on LI-ION Battery Thermal Management in Low Tempera...

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作者： mohammed abdullahi 华南理工大学

学位级别：硕士

随着环境污染问题的日益突出和传统化石燃料的日益短缺,世界各国都开始重视电动汽车的发展。锂离子电池作为电动汽车的动力源,只能在20℃-40℃的工作温度范围内表现良好。也就是说,极端气候会严重影响锂离子电池的性能。因此,电池热管... 详细信息

随着环境污染问题的日益突出和传统化石燃料的日益短缺,世界各国都开始重视电动汽车的发展。锂离子电池作为电动汽车的动力源,只能在20℃-40℃的工作温度范围内表现良好。也就是说,极端气候会严重影响锂离子电池的性能。因此,电池热管理成为近年来的研究热点之一。可以根据不同的温度区间将电池热管理分为电池冷却和电池加热两个方面。目前,大多数研究人员关注的是电池冷却问题,而锂离子电池加热面临着严重挑战,但科学家和研究人员却对此关注较少。锂离子电池在低温环境下的性能退化极大地限制了锂离子动力电池在寒冷气候和高纬度地区的应用,因此,有必要对低温区间的电池热管理进行系统深入的研究。本文以18650锂离子电池为研究对象,开展低温区间的电池热管理的研究,为电池热管理系统的设计提供参考。本文的主要工作如下:(1)讨论了低温对锂电池充电能力、容量和功率的影响。现有的研究成果表明,在低于零度时,锂离子电池的性能会下降。通过对不同电池加热方法的分析比较,选择石墨烯加热片进行本课题的研究工作。(2)使用商用ANSYS FLUENT软件计算电池在加热过程中的温度变化。首先通过ANSYS Workbench平台建立2D物理模型并对其进行简化处理,模型采用六面体网格划分方式,将模型划分为231,336个网格。其次,把网格文件导入到FLUENT 2020R2中并设置模型设置边界条件、指定控制方程的离散格式。最后利用CFD-post软件对数值计算结果进行处理和分析。(3)进行实验以收集实际的电池温度变化数据,从而验证模型的有效性。实验采用了一个2×5(包含10节电池)电池组。还采用了6个具有不同最高温度(60℃,70℃,80℃,90℃,100℃,110℃)的石墨烯加热片。这些石墨烯加热片尺寸相同,为360mm×65mm(5*30cm)且工作电压为12V,电流为8A。实验目标是将电池从零下20度加热到20度。实验结果表明,电池温度变化与仿真结果基本一致。

关键词：电动汽车锂离子电池热管理石墨烯加热片数值模拟

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Antihyperglycaemic activity of ethylacetate extract of Chlorophytum alismifolium in type 2 diabetes:The involvement of peroxisome proliferator-activated receptor-γand dipeptidyl peptidase-4

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Journal of Integrative Medicine 2021年第1期19卷 78-84页

作者： Abdulhakim Abubakar abdullahi Balarabe Nazifi Idris mohammed Maje Yusuf Tanko Joseph Akpojo Anuka Ezzeldin Mukthar Abdurahman Department of Pharmacology and Therapeutics Ahmadu Bello UniversityZaria PMB-1044Nigeria Department of Pharmacology and TherapeuticsBayero UniversityKano PMB-3011Nigeria Department of Human PhysiologyAhmadu Bello UniversityZaria PMB-1044Nigeria Department of Pharmacognosy and Drug DevelopmentAhmadu Bello UniversityZaria PMB-1044Nigeria

Objective:This research is to investigate the antihyperglycaemic activity and the underlying mechanisms of action of the ethylacetate extract of Chlorophytum alismifolium(EACA)tubers in a type 2 diabetes ***:The tubers were processed and sequentially extracted in hexane followed by ethylacetate,using a Soxhlet apparatus,and subjected to gas chromatography-mass spectrometry(GC–MS).The acute toxicity of EACA was investigated in albino Wistar *** antihyperglycaemic study was carried out using high-fat diet(pelletized diet and margarine in the ratio of 10:1 and 20%fructose solution)and streptozotocin-induced hyperglycaemic Wistar *** effects of the extract(150,300 and 600 mg/kg)on blood glucose level,insulin,peroxisome proliferator-activated receptor-c(PPAR-c)and dipeptidyl peptidase-4(DPP-4)were evaluated using enzyme-linked immunosorbent ***:The oral median lethal dose in Wistar rats was estimated to be>5000 mg/*** with EACA at all doses significantly reduced the fasting blood glucose levels,compared to the hyperglycaemic control,and over *** of EACA increased the serum insulin and PPAR-c levels while decreasing DPP-4 ***–MS analysis revealed the presence of 13 compounds,with isothiazole and isoxazolidine covering total area of 24.6%and 22.69%,***:The findings from this study showed that EACA has important compounds with beneficial effect in type 2 diabetes and acts by increasing insulin secretion and PPAR-c level and decreasing DPP-4 activity.

关键词： Chlorophytum alismifolium Diabetes mellitus Gas chromatography-mass spectrometry Insulin Peroxisome proliferator-activated receptor-c Dipeptidyl-peptidase 4

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Prevalence and risk factors associated with malaria infection among pregnant women in a semi-urban community of north-western Nigeria

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Infectious Diseases of Poverty 2015年第1期4卷 193-197页

作者： Sani abdullahi Fana mohammed Danladi Abubakar Bunza Sule Aliyu Anka Asiya Umar Imam Shehu Usman Nataala Author details 1 Department of Medical Microbiology Faculty of Medical Laboratory ScienceUsmanuDanfodiyo UniversitySokotoNigeria Department of Biological Sciences UsmanuDanfodiyo UniversitySokotoNigeria

Background:Malaria during pregnancy remains a serious public health problem,with substantial risks for the mother,her foetus and the *** aim of this study was to determine the prevalence of malaria and possible risk factors for malaria infection among pregnant women in a semi-urban area in north-western *** women are among the most susceptible to malaria *** of their malaria infection status is an important yardstick to measure the effectiveness of any malaria control ***:We conducted a cross sectional study in the semi-urban area of Argungu,Kebbi State *** hundred and fifty five pregnant women were included in the study after informed verbal consent was *** each participant,the socio-demographic profile,stage of pregnancy and attitude to the use of insecticide-treated nets(ITNs)were investigated using a *** blood samples were collected and thick blood smears were prepared and stained with Giemsa stains to check for malaria *** associations between age,education level and use of ITNs with occurrence of malaria infection during pregnancy were analysed using the chi-square ***:One hundred and six(41.6%)out of 255 pregnant women were infected with malaria parasites,with a mean parasite density of 800 parasitesμl−*** was found that prevalence and parasite density decreased as age *** chi-square test indicated that a lack of education and non-usage of ITNs were significantly associated with malaria ***:Malaria is still a major public health issue among pregnant women mainly due to illiteracy and non-compliance to using *** awareness about malaria preventive measures and early attendance of antenatal care services will help to reduce malaria and,consequently,its associated morbidities and mortalities.

关键词： Malaria Pregnant women Mean parasite density Prevalence Risk factors Giemsa stain Argungu

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Phytochemical screening and anticonvulsant studies of ethyl acetate fraction of Globimetula braunii on laboratory animals

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Asian Pacific Journal of Tropical Biomedicine 2014年第4期4卷 285-289页

作者： Musa Mumammad Aliyu abdullahi Isma'il Musa Muhammad Ja'afar Kanial Magaji Garba mohammed Department of Pharmaceutical and Medicinal Chemistry Ahmadu Bello University Department of Pharmaceutical and Medicinal Chemistry Usmanu Danfodio University Chemistry Advance Laboratory Sheda Science and Technology Complex Department of Pharmacology and Therapeutics Ahmadu Bello University

Objective:To investigate the phytochemical properties and the anticonvulsant potential of the ethyl acetate soluble fraction of ethanol leaf extract of Globimetida braunii,a plant used in ethnomedicine for the treatment of ***:The phytochemical screening was carried out using standard protocol while the anticonvulsant activity was studied using maximal electroshock test in chicks,pentylenetetrazole and 4-aminopyridine—induced seizures in ***:The preliminary phytochemical screening carried out on the crude ethanol extract revealed the presence of saponins,carbohydrates,flavonoids,tannins,anthraquinones and ***,tannins,flavonoids and steroids/terpenes were found to be present in the ethyl acetate fraction,In the pharmacological screening,150 mg/kg of the fraction protected 83.33%of animals against pentylenetetrazole-induced seizure in mice whereas sodium valproate a standard anti-epileptic drug offered 100%*** the 4-aminopyridine-induced seizure model,the fraction produced a significant(P<0.05)increase in the mean onset of seizure in unprotected *** fraction did not exhibit a significant activity against maximal electroshock *** median lethal dose of the fraction was found to be 1261.91 mg/***:These results suggest that the ethyl acetate fraction of Globimetula braunii leaves extract possesses psychoactive compound that may be useful in the management of petit mal epilepsy and lend credence to the ethnomedical use of the plant in the management of epilepsy.

关键词： Epilepsy Globimetula braunii Seizure Medicinal Pentylenetetrazole

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Pattern, Precipitants and Short Term Outcome of Heart Failure Patients Managed at Federal Medical Centre Nguru, a Tertiary Health Centre in Yobe State Northeastern Nigeria

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International Journal of Clinical Medicine 2018年第5期9卷 432-444页

作者： Musa mohammed Baba Faruk Buba mohammed abdullahi Talle Habu Abdul Department of Internal Medicine Federal Medical Centre Nguru Nguru Nigeria Department of Medicine College of Medical Sciences University of Maiduguri Maiduguri Nigeria

Heart Failure (HF) is a syndrome characterized by typical symptoms (e.g. breathlessness, ankle swelling and fatigue) that may be accompanied by signs (e.g. elevated jugular venous pressure, pulmonary crackles and peripheral oedema) caused by a structural and/or functional cardiac abnormality, resulting in a reduced cardiac output and/or elevated intracardiac pressures at rest or during stress. Clinical studies investigating the aetiological patterns of heart failure in Sub-Saharan Africa (SSA) revealed that hypertension, cardiomyopathy and rheumatic heart disease account for more than two-thirds of cardiac disease cases. The objective of this study therefore is to assess the pattern, precipitating factors and short term outcome of heart failure among patients admitted into our hospital. Method: The study was a prospective cross-sectional type conducted among in patients with heart failure in the medical ward of the hospital. Results: A total of three and fifty four (354) subjects were recruited into the study, comprising one hundred and twenty nine males (36.4%) and two hundred and twenty five (63.4%) females. Majority of the patients were admitted in NYHA functional class IV. This however improved to class II at discharge though few were discharged in NYHA class III. Heart failure secondary to progressive hypertensive heart disease was the most common (39.0%) followed by peripartum cardiomyopathy (22.6%) while idiopathic dilated cardiomyopathy (11.0%) and rheumatic heart disease (7.3%) were the third and fourth causes of heart failure respectively. The most common precipitating factor for heart failure in this study was chest infection (44.9%). In conclusion, the study revealed that progressive hypertensive heart disease was the leading cause of heart failure, followed by peripartum cardiomyopathy while idiopathic dilated cardiomyopathy and rheumatic heart disease were ranked third and fourth causes of heart failure respectively. Though myocardial infarction is on

关键词： Patterns Precipitant Short Term Outcome Heart Failure

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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

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Nasal Response from Formaldehyde Exposure Used as Cadaver Preservative among Pre-Clinical Medical Students in a Nigerian Medical College

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International Journal of Otolaryngology and Head & Neck Surgery 2014年第4期3卷 173-178页

作者： mohammed abdullahi abdullahi Daudu Zagga Kufre Robert Iseh Stanley Baba Amutta Daniel Aliyu Department of Anatomy College of Health Science Usman Danfodiyo University Sokoto Nigeria Department of Ear Nose and Throat Usman Danfodiyo University Teaching Hospital Sokoto Nigeria

Background: Formaldehyde is commonly used for cadaver preservation in most anatomy laboratories with medical students at risk of acute toxic reactions involving the mucosal surface of the upper respiratory tract. Aim: To assess the nasal induced physical reactions from formaldehyde exposure among pre-clinical medical students. Materials and Method: This is a cross sectional, anonymous questionnaire-based study that included 119 preclinical medical students who took human anatomy laboratory course in the year 2012 at the College of Health Science of the Usman Danfodiyo University, Sokoto, Nigeria. Results: One hundred and nineteen students responded to the questionnaires. There were 82 males and 37 females with a ratio of 2.2:1. Fifty nine (49.6%) of the respondents had watery rhinorrhea, nose itching 41 (34.5%), excessive sneezing 34 (28.6%), nasal obstruction 32 (26.9%), hyposmia 23 (19.3%) and 6 (5%) epistaxis. Thirty (29.2%) respondents had persistent nasal symptoms throughout the dissection session and nasal obstruction accounted for 40% of those affected. Majority of the respondents 113 (95%) had no knowledge of health hazards and precautions against formaldehyde exposure. Conclusion: Watery rhinorrhea, followed by nasal obstruction were the most common nasal symptoms which were persistent in 36.7% and 40% of the respondents respectively throughout the anatomy dissection sessions. Ninety five percent of the respondents had no knowledge of health hazards and precautions against formaldehyde exposure, therefore we recommend creation of awareness and precautionary measures against formaldehyde exposure in our Nigerian medical schools.

关键词： Formaldehyde Nasal Symptoms Health Hazards Medical Students

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