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Journal of Geoscience and Environment Protection 2016年第1期4卷 84-92页

作者： Abba aliyu Kasim Abubakar Aminu usman Department of Soil Water Land Engineering & Management Sam Higginbottom Institute of Agriculture Technology & Sciences Allahabad India

Soil surface wetness is indispensable land surface parameter in agriculture, hydrology and environmental engineering. This paper explores the relationship between surface radiant temperature and fractional vegetation cover derived from satellite imagery to estimate soil surface wetness (triangle method) in Allahabad district. The pixel distributions create triangular shapes because the range of surface radiant temperature decreases as the amount of vegetation cover increases and sufficient number of pixels exists. A very weak correlation is found between the simulated soil surface wetness and ground measured soil moisture at deeper soil layers (R2 < 0.15) on all the dates under investigation. This is because the drying rates at the surface discontinue to be linearly correlated to that at lower levels (depths). The standing water pixels distort the shape of the triangle especially at lower left edge of the triangle. This distortion is removable. The spatial and temporal inhomogeneity of soil surface wetness is examined.

关键词： Triangle Method Soil Surface Wetness Surface Radiant Temperature Fractional Vegetation Cover

Assessment of breast cancer immunohistochemistry and tumor characteristics in Nigeria

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World Journal of Clinical Oncology 2020年第11期11卷 935-944页

作者： usman Malami aliyu Abdulrahaman Auwal Musa Department of Radiotherapy and Oncology Usmanu Danfodiyo University/Teaching HospitalSokoto 840212Nigeria Department of Histopathology Usmanu Danfodiyo University Teaching HospitalSokoto 840221Nigeria

BACKGROUND Female breast cancer is the leading type of cancer worldwide with an incidence of approximately 2.1 million in *** receptor status plays a vital role in its *** To determine the molecular expression pattern of biomarkers in breast cancer and their correlation with tumor *** This prospective study was designed to analyze expression patterns of estrogen receptor(ER),progesterone receptor(PR)and human epidermal growth factor receptor(HER2/neu)in breast cancer *** dataset has been taken from the Department of Radiotherapy and Oncology of usmanu Danfodiyo University Teaching Hospital Sokoto,Nigeria from 1 January 2015 to 2 December *** dataset had 259 records and 7 *** version 23.0 for statistical analysis was *** data analyzed demographic and other clinicopathological characteristics as categorical *** mean and standard deviation were determined for the quantitative *** A total of 259 breast cancer cases were included in the *** mean age was 48.3±11.0,with an age range of 26-80 years and a median age of 46 *** morphological categories were invasive ductal carcinoma 258(99.6%)and invasive lobular carcinoma 1(0.4%).ER,positivity increased in 73 patients(50%)under the age of 50 years,as well as PR positivity increased in 34 patients(23.6%)under the age of 50 ***/2neupositivity decreased in 8 patients(5.6%)under the age of 50 *** receptors were statistically significant with clinicopathological characteristics(P<0.05).CONCLUSION Our study showed that ER,PR and HER2/neuexpression had a strong correlation with age,tumor grade,tumor size and lymph node ***,hormone receptor assessment is highly recommended because of its significance in clinical management and prognostication.

关键词： Breast cancer Hormonal receptors Sokoto state Tertiary Health Institution Northwestern Nigeria

Spatio-Temporal Assessment of Vegetation Resource Dynamics in Nigeria from SPOT Satellite Imageries

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American Journal of Climate Change 2019年第4期8卷 502-519页

作者： Sadiq Abdullahi Yelwa aliyu Bilya Sanda Umar usman Department of Environmental and Resources Management Faculty of Engineering and Environmental Design Usmanu Danfodiyo University Sokoto Nigeria Department of Mathematics and Statistics Faculty of Science Usmanu Danfodiyo University Sokoto Nigeria

Vegetation resources in Nigeria are of vital importance for the sustainable development of the country. However, this essential resource is in danger due to the effect of anthropogenic and climate induced impacts. Currently desert encroachment which cuts across the Sahel is affecting most of the states in the northern part of the country particularly the eleven states considered by the Federal Ministry of Environment in Nigeria as the frontline states. Several studies on the Nigerian environment have shown that there are serious threats to the general environment particularly vegetation. Due to population growth and the need for housing as well as the expansion of the over-utilised farmlands across these states, places considered as reserved areas across the country are being exploited to the detriment of the vegetal resources particularly the forest and rangeland areas. This study utilized Idrisi TerrSet (version 18) raster-based remote sensing and GIS software to analyse seventy two (72) dekadal Normalised Vegetation Index (NDVI) imageries from SPOT satellite covering Nigeria in order to assess the anthropogenic and likely climatic impacts on the vegetal resources using the forward t-mode Principal Component Analysis (PCA) with standardised principal components. Results indicated that Component 1 which explains about 69% of the 72 time-series NDVI imageries shows typical vegetation cover over the study area within the time period under study. While component two indicated a cyclic trend differentiating the ENSO events of 1999 and 2009;component three indicated positive anomaly pattern of vegetation NDVI mostly within Sokoto, Kebbi, Kano, Jigawa and the northern parts of Bauchi, Yobe and Borno states. However, Component four imagery indicated a likely link to the 2009 flood that affected Kainji dam and rivers Niger and Benue. For a better result, the integration of socio-economic and high spatial resolution data into an assessment of this kind in future studies is

关键词： Vegetation Resources Desertification NDVI SPC

Mathematical Model for the Transmission Dynamics of Zika Virus Infection with Combined Vaccination and Treatment Interventions

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Journal of Applied Mathematics and Physics 2017年第10期5卷 1964-1978页

作者： Sulaiman usman Ibrahim Isa Adamu Huzaifa aliyu Babando Department of Mathematics Modibbo Adama University of Technology Yola Nigeria

In this paper, we studied the transmission dynamics of ZIKV in the presence of a vector under the combined effects of treatment and vaccination in a hypothetical population. The disease-free εo and endemic ε1 equilibria were established with local stability on εo. We established the basic reproduction number Ro which served as a threshold for measuring the spread of the infection in the population using the next-generation matrix and computed its numerical value to be Ro = 0.0185903201 using the parameter values. It was established that the disease-free equilibrium εo is locally asymptotically stable since Ro < 1;meaning ZIKV infection would be eradicated from the population. The computational results of the study revealed that combining the two interventions of vaccination and treatment concomitantly proffers an optimal control strategy in taming the transmission of the virus than a single intervention strategy.

关键词： Zika Virus Infection Flavivirus Compartment Asymptomatic Basic Reproduction Number Local Asymptotic Stability

Harmonics Measurement Analysis for a Stand Alone Photovoltaic System with Linear and Non-Linear Loads

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材料科学与工程（中英文A版） 2014年第5期4卷 183-189页

作者： Hamisu usman Ramatu aliyu Abarshi Sani M. Lawal Electrical/Electronic Engineering Department College of Engineering Kaduna Polytechnic PMB 2021 Kaduna Nigeria

Nowadays Photovoltaic systems have become one of the dominant renewable energy sources for generating electricity in the world. The photovoltaic system is a clean, friendly and non-polluting energy source with the reduced carbon dioxide (CO 2 ) emission, when compared with the conventional energy sources, which pollutes the environment and makes it hazardous to human health. However, the output wave forms of Voltage and Current generated by the Photovoltaic systems produce harmonics. This is due to the power electronic converters and the non-linear loads connected to the PV systems. In this paper, we present experimental results and analysis for an interactive standalone Photovoltaic system connected with different linear and non-linear loads. The experiment was performed with HIOKI 3196 power quality analyzer. The percentage of the total harmonics distortion (THD) of the Voltage (THDV) and Current (THD I ) have been studied in this paper. Results of the THD are presented and compared with IEEE 519-1992 standard.

关键词：光伏发电系统非线性负载谐波失真测量分析独立光伏系统电能质量分析仪可再生能源电子转换器

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