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Assessment of Heavy Metals Concentration in Shore Sediments from the Bank of River Benue, North-Central Nigeria

Journal of Geoscience and Environment Protection 2018年第4期6卷 35-48页

作者： ejembi emmanuel Terver Sombo Jonathan Ugwanyi Department of Natural and Applied Sciences Namibia University of Science and Technology Windhoek Namibia Department of Physics University of Agriculture Makurdi Nigeria

Heavy metals are elements, whose density is greater than water. They are generated from our environment. Rocks, sediments, plants, water and aerosol particles represent the carriers of heavy metals. An accumulated amount of heavy metal in the body, either by inhalation, food or drinking water, can cause an adverse health effect to human. The Benue river passed through the town of makurdi, was high population of the inhabitant of Benue State dwells. The industrial and agricultural activities carried out in this region, increase the concentration of heavy metals. This may result to adverse health effect on the inhabitant of Makurdi. The objectives of this work were to determine the heavy metal concentration and its site contaminations along the bank of river Benue, Makurdi. An inductively coupled plasma optical emission spectrometry (ICP-OES) was used to determine the heavy metals concentration. The metals concentrations (Iron, Copper, Manganese, Lead, Zinc, Chromium, Arsenic, and Cadmium) of the three stations were found. This ranges from 3.55 - 9454.0 mg/kg, 0.20 - 8928.0 mg/kg and 2.80 - 13,657 mg/kg for stations 1, 2 and 3. With Fe recorded as the highest concentration in the sediment, this value is compared with the World Health Organisation (WHO) and World Surface Rock Average (WSRA) standard. The assessment on contamination status of heavy metals in the riverbank, showed low degree of contamination in stations 1 and 2, and moderate degree in station 3. The degree of enrichment to heavy metals in all the stations is deficient to minimal. The evaluation of the results of pollution load index (PLI) from this present study indicated PLI 1 in stations 1 and 3. Hence stations 1 and 3 are polluted, while station 2 is not polluted with heavy metals.

关键词： Heavy Metals Site Contamination Parameter ICP-OES

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Assessment of Spatial Distribution and Temporal Trends of Precipitation and Its Extremes over Nigeria

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American Journal of Climate Change 2021年第3期10卷 331-352页

作者： Moses Owoicho Audu emmanuel ejembi Tertsee Igbawua Department of Physics Joseph Sarwuan Tarka University Makurdi Nigeria Department of Natural and Applied Sciences Namibia University of Science and Technology Namibia

This study analyzed the spatial distribution and temporal trends of precipitation and its extremes over Nigeria from 1979-2013 using climate indices, in order to assess climatic extremes in the country. Daily precipitation data used in this study were obtained from Nigeria Meteorological Agency (NIMET), Lagos. The study used climate indices developed by the Expert Team on Climate Change Detection (ETCCDI) for assessing extreme precipitation. Sen’s slope estimator and Mann-Kendall trend test were employed in data analysis. Results revealed that precipitation and its extremes varied spatially across Nigeria. Significant negative trends were observed in most of the precipitation indices for the period under study. Furthermore, significant downward trends were observed in the CWD (Consecutive Wet Day) while the CDD (Consecutive Dry Day) showed significant upward trends in all the regions. These spatial and temporal changes indicate that Nigeria’s climate is trending towards a warmer and drier condition, which could be attributed to global warming-induced climate change;which altered historical rainfall patterns thereby leading to extreme events. The findings of this study have provided useful information in understanding the extreme events that are assumed by the general populace to be normal recurrent events in Nigeria. The results of the analysis of yearly and decadal changes in precipitation totals and extreme values for the last 35 years (1979-2013) suggest the likelihood of severe impacts on water resources, agriculture, and water-sensitive economic activities

关键词： Climate Indices Climate Extreme Climate Change Spatial Pattern Temporal Trends Nigeria

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Assessment of Radionuclide Content of Shore Sediments Collected from the Bank of River Benue, North-Central Nigeria

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Journal of Geoscience and Environment Protection 2017年第12期5卷 57-65页

作者： Terver Sombo ejembi emmanuel Jonathan Ugwuanyi Department of Physics University of Agriculture Makurdi Nigeria Department of Natural and Applied Sciences Namibia University of Science and Technology Windhoek Namibia

Ionizing Radiation emitted from radionuclide has an adverse effect on human health. A continuing population exposure to naturally occurring radioactive materials (NORMS) found in our environment is one of the major scientific subjects that attract public attention. The assessment of radionuclide content of shore sediments of river Benue-North Central Nigeria was carried out using gamma-ray spectrometry. The activity concentrations of U-238, Th-232 and K-40 were found to have an average concentration of 1.17, 3.31 and 405.95 Bq·kg-1 respectively. The values gotten from present study were compared with the world average values. World average values of U-238, Th-232 and K-40 are 50 Bq·kg-1, 50 Bq·kg-1 and 500 Bq·kg-1 respectively. The mean concentration of daughter radionuclides generated from U-238, Th-232 was 4.32, 10.37, 5.24, 3.86, 11.87, and 6.52 for Bi-212, Pb-212, Bi-214, Pb-214, Ra-226 and Ac-228, respectively. The mean of the absorbed dose, Annual effective dose equivalent, for radium equivalent activity, and external hazard index, were evaluated to be 19.45 nGy·h-1, 23.82 μSv·y-1, 37.16 Bq·kg-1, 0.10 mSv·y1, below the permissible limit of 57 nGy·h-1, 70 μSv·y-1, 370 Bq·kg-1 and 1 mSv·y-1 respectively. These shore sediments from river Benue are therefore, radiologically safe for construction and other domestic and industrial purposes.

关键词： Radionuclides Sediments Gamma Spectrometry Radiological Parameter

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Measurement of Noise Pollution in Northern Industrial Areas of Windhoek, Namibia

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Journal of Environmental Protection 2019年第9期10卷 1144-1154页

作者： Sylvanus Ameh Onjefu emmanuel ejembi Leonard Agbo Onjefu Department of Natural and Applied Sciences Namibia University of Science and Technology Windhoek Namibia Department of Civil and Environmental Engineering Namibia University of Science and Technology Windhoek Namibia

The increase in industrial activities and vehicular movement along the northern industrial area of Windhoek has vastly increased the amount of traffic noise and other noise pollution in the area. Noise pollution has an adverse health effect to human population, when exposed for a long period. Residence in proximate communities along the north industrial area and those working in the various industries located in the area may be affected, when the noise pollution level exceed the permissible standard for human exposure. A sound level meter was used to measure the amount of noise pollution at the streets of the northern industrial area. The measurements were done during the daytime, at a time interval of 2 hours, from 08:00 am - 06:00 pm. The amount of noise pollution obtained from the study ranges from (64 - 72) dB (A), with a maximum of 72 dB (A) in Bonsmara Street, (67.4 - 75.3) dB (A), with a maximum of 75.3 dB (A) in New Castle Street, (60.5 - 81.0) dB (A), with a maximum of 72.3 dB (A) in Braham Street. (62.5 - 72.3) dB (A), with a maximum of 82.3 dB (A) in Hosea Kutako Street, (66.0 - 82.3) dB (A), with a maximum of 76.8 dB (A) in Simmentaler Street and (65.1 - 76.8) dB (A), with a maximum of 76.8 dB (A) in Dortmund Street. The variation of noise level index L10, L50, L90 and Leq, Noise Climate (NC) and Traffic Noise index (TNI) were calculated. The maximum noise pollution values obtained from the study were higher than the WHO recommended limit of 70 dB (A).

关键词： Noise Pollution Northern Industries Sound Intensity Source of Noise

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Preliminary Investigation of Total Ozone Column and Its Relationship with Atmospheric Variables

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Atmospheric and Climate Sciences 2023年第2期13卷 225-239页

作者： Moses Owoicho Audu ejembi emmanuel Otor Daniel Abi Daniel Audu Ogbe Chibuoke Kingsley Arinze Department of Physics Joseph Sarwuan Tarka University (Federal University of Agriculture) Makurdi Nigeria Department of Natural and Applies Sciences Namibia University of Science and Technology Windhoek Namibia Department of Chemical Science Yaba College of Technology Lagos Nigeria

This study attempts to investigate the interaction between lower and upper atmosphere, employing daily data of Total Ozone Column (TOC) and atmospheric parameter (cloud cover) over Nigeria from 1998-2012;in order to study the dynamic effect of ozone on climate and vice versa. This is due to the fact that ozone and climate influence each other and the understanding of the dynamic effect of the interconnectivity is still an open research area. Monthly mean daily TOC and cloud cover data were obtained from the Earth Probe Total Ozone Mass Spectroscopy (EPTOMS) and the International Satellite Cloud Climatology Project (ISCCP)-D2 datasets respectively. Bivariate analysis and Mann Kendall trend tests were used in data analysis. MATLAB and ArcGIS software were employed in analyzing the data. Results reveal that TOC increased spatially from the coastal region to the north eastern region of the country. Seasonally, the highest value of TOC was observed at the peak of rainy season when cloud activity is very high, while the lowest value was recorded in dry season. These variations were attributed to rain producing mechanisms and atmospheric phenomena which influence the transport and distribution of ozone. Furthermore, the statistical analysis reveals significant relationship between TOC and low and middle cloud covers in contrast to high cloud cover. This relationship is consistent with previous studies using other atmospheric variables. This study has given scientific insight which is useful in understanding the coupling of the lower and upper atmosphere.

关键词： Total Ozone Column Cloud Cover Ozone Depletion Atmospheric Variables EPTOMS Nigeria

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Modern drug discovery for inflammatory bowel disease: The role of computational methods

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World Journal of Gastroenterology 2023年第2期29卷 310-331页

作者： Titilayo Omolara Johnson Augustina Oduje Akinsanmi Stephen Adakole ejembi Olugbenga Eyitayo Adeyemi Jane-Rose Oche Grace Inioluwa Johnson Abayomi emmanuel Adegboyega Department of Biochemistry University of JosJos 930222PlateauNigeria Faculty of Clinical Sciences College of Health SciencesUniversity of JosJos 930222PlateauNigeria

Inflammatory bowel diseases(IBDs)comprising ulcerative colitis,Crohn’s disease and microscopic colitis are characterized by chronic inflammation of the gastrointestinal *** has spread around the world and is becoming more prevalent at an alarming rate in developing countries whose societies have become more *** therapy,intestinal microecology,apheresis therapy,exosome therapy and small molecules are emerging therapeutic options for ***,it is thought that low-molecular-mass substances with good oral bio-availability and the ability to permeate the cell membrane to regulate the action of elements of the inflammatory signaling pathway are effective therapeutic options for the treatment of *** small molecule inhibitors are being developed as a promising alternative for IBD *** use of highly efficient and time-saving techniques,such as computational methods,is still a viable option for the development of these small molecule *** computeraided(in silico)discovery approach is one drug development technique that has mostly proven *** approaches when combined with traditional drug development methodology dramatically boost the likelihood of drug discovery in a sustainable and cost-effective *** review focuses on the modern drug discovery approaches for the design of novel IBD drugs with an emphasis on the role of computational *** computational approaches to IBD genomic studies,target identification,and virtual screening for the discovery of new drugs and in the repurposing of existing drugs are discussed.

关键词： Inflammatory bowel disease Computer-aided drug design Janus Kinase Molecular docking Genome-wide association study Molecular dynamics simulation

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