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Journal of Water Resource and Protection 2009年第6期1卷 456-468页

作者： david kofi essumang Christian. Kweku ADOKOH Joseph AFRIYIE Esther MENSAH 不详

The study looked at the levels of polycyclic aromatic hydrocarbons (PAHs) in leachates from a solid waste disposal site and an effluent from an oil refinery in some water bodies around Accra. Sixteen (PAHs) were extracted simultaneously by solid phase and analysis by gas chromatograph. The results of this study gener-ally demonstrated that there were elevated levels of PAHs in the water sample of the Densu River, Chemu, Korle and Kpeshi Lagoons. The average concentration of PAHs in the water ranged from 0.000 of many of the PAHs to 0.552µg/L, for Acenapththene to 11.399µg/L for Benzo (ghi) perylene of the Chemu Lagoon, 0.00µg/L for Benzo (a) Pyrene to 8.800µg/L for Benzo (ghi) perylene (Korle Lagoon) and 0.052µg/L for Pyrene to 4.703ug/L for Acenaphthylene of the Kpeshi Lagoon and 0.00µg/L for pyrene to Acenaphthylene 2.926µg/L of the Weija Dam. Concentrations ranging from below detection level to 14.587µg/L were also recorded at the Oblogo solid waste dump and it’s environ. The Weija dam supply over two million gallons of portable water daily to the people of Accra and the levels of the PAH determined is worrying, as a result, the Oblogoh disposal site ought to be re-located to avert any possible epidemic.

关键词： Accra Metropolitan Assembly (AMA) Oblogo Dumping Site Weija Dam Densu River PAHs Chemu Lagoon Korle Lagoon Kpeshi Lagoon

Pesticide and Nutrient Loads of Lake Bosomtwe in the Ashanti Region of Ghana

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Journal of Water Resource and Protection 2021年第10期13卷 794-806页

作者： Collins Kuffour david kofi essumang Hugh Komla Akotoye Richard Amankwah Kuffour Janice Dwomoh Abraham Department of Environmental Health and Sanitation Education Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Mampong Ashanti Region Ghana School of Physical Sciences University of Cape Coast Cape Coast Central Region Ghana Department of Environmental Science University of Cape Coast Cape Coast Central Region Ghana Department of Biological Sciences Education Akenten Appiah-Menka University of Skills Training and Entrepreneurial Development Mampong Ashanti Region Ghana

Pollution of Lake Bosomtwe is a major concern in Ghana due to its derived socio-economic benefits such as employment, ecotourism and major protein source to the people in the basin. Besides these benefits, the lake water is used for domestic purposes and has since served as the drinking water source to the people. However, the use of agrochemicals within the basin has intensified within the last decade. The problems associated with fertilizer and pesticide use in the Bosomtwe basin seem to carry with it a higher price, which, if not identified and checked, will overshadow the desired benefits of the lake. This study assesses pesticide and nutrient loads of Lake Bosomtwe in the Ashanti Region of Ghana. Fifty-four (54) lake water samples were collected from September 2016 to February 2017. Pesticide samples were extracted using the solid phase extraction method and GCMS to identify the pesticides present in the water samples and determine their loads. The data obtained were analyzed using Statistical Product Service Solutions (SPSS version 20) for descriptive statistics. The concentration of dichlorvos was a bit lower when compared with the WHO/USEPA guidelines of 5 ppb for surface water. Diazinon had a mean concentration of 0.28 ± 0.03 ppb which was higher than the WHO 0.05 ppb and USEPA 0.04 ppb for surface water bodies. The detection of diazinon confirms the findings from the field survey, which revealed that diazinon, is an active ingredient of a pesticide with a trade name “Akate suro”, which was extensively used by cocoa farmers along the banks of the lake. The mean concentration recorded for nitrate and phosphate were 0.15 ± 0.05 mg/L and 0.40 ± 0.12 mg/L respectively. The pesticides application inventory and implications of pesticide and nutrient loads on the lake are discussed in the paper.

关键词： Organochlorine Organophosphorus Pesticide Fertilizer Bosomtwe

Root System Traits Contribute to Variability and Plasticity in Response to Phosphorus Fertilization in 2 Field-Grown Sorghum[Sorghum bicolor(L.)Moench]Cultivars

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Plant Phenomics 2023年第1期5卷 6-21页

作者： Michael O.Adu Paul A.Asare david O.Yawson Kwadwo K.Amoah kofi Atiah Matthew K.Duah Alex Graham Department of Crop Science School of AgricultureCollege of Agriculture and Natural SciencesUniversity of Cape CoastCape CoastGhana Centre for Resource Management and Environmental Studies(CERMES) The University of the West IndiesCave Hill CampusP.O.Box 64Bridgetown BB11000Barbados Department of Soil Science School of AgricultureCollege of Agriculture and Natural SciencesUniversity of Cape CoastCape CoastGhana

Due to roots'physical and physiological roles in crop productivity,interest in root system architecture(RSA)and plasticity in responses to abiotic stresses is *** is significant for the food security of millions of *** deficiency is an important limitation of sorghum *** is little information on the RSA-based responses of sorghum to variations in external P supply([P]_(ext)).This study evaluated the phenotypic plasticity and RSA responses to a range of[P]_(ext) in 2 sorghum *** results showed that both genotypes responded to[P]_(ext) but with significant variations in about 80%of the RSA traits *** biomass and most RSA traits increased with increasing[P]_(ext).Plasticity was both genotype-and *** most RSA traits,the white sorghum genotype showed significantly higher plasticity than the red genotype,with the former having about 28.4%higher total plasticity than the *** traits,such as convex area,surface area,total root length,and length diameter ranges,showed sizeable genetic *** biomass had a high degree of plasticity,but root number and angle traits were the leading contributors to *** results suggested 2 root trait spectra:root exploration and developmental spectrum,and there was an indication of potential trade-offs among groups of root *** is concluded that RSA traits in sorghum contribute to variability and plasticity in response to[P]_(ext).Given that there might be trade-offs among sorghum root traits,it would be instructive to determine the fundamental constraints underlying these trade-offs.

关键词： Root instru constraints

The Design of a Mobile Phone-Based Remote-Control Application to Submersible Motor for Effective Water Supply

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Journal of Sensor Technology 2022年第2期12卷 19-31页

作者： Winfred Adjardjah david Bright kofi Arthur Alex Ewuam Kingsley Nunoo Department of Electrical and Electronic Engineering Takoradi Technical University Takoradi Ghana

In the last few decades, several monitoring systems integrated with water level detection have been the major research focus. Production boost and its sustainability depend mainly on sustainable water supply, measuring water level, and avoiding waste of water is an essential task for all stakeholders. Therefore, the aim of this paper is to design and implement a mobile phone-based remote control. This will be applied to control the operation of a submersible motor in a water tank. The water level in the tank is detected and the device remotely turns the motor pump on/off. The design process is accomplished by developing an android application that works on GSM technology to manage the filling of water tank. An AT89C51 microcontroller is used for the desired programming. At the transmitting end, sensor is used for level detection and GSM module is used to send the information to user. According to this information, user controls the on/off operation of the pump. A SIM card is required for its operation and it works on attention (AT) commands. After the design and implementation of the device, the test results showed that all features of the device worked properly, and the device functions exactly as expected. More significantly, the paper has shown that ultrasonic sensors can be used to determine the level of water in a water tank and a GSM module can be used to control a submersible pump. The design and implementation of this device can help to reduce waste of time and power. Ultimately, it avoids water wastage thereby ensuring availability, conservation, and sustainability of water supply.

关键词： Water Supply Submersible Motor Pump Mobile Phone GSM Android

High-efficiency,large-area,topologyoptimized metasurfaces

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Light(Science & Applications) 2019年第1期8卷 749-757页

作者： Thaibao Phan david Sell Evan W.Wang Sage Doshay kofi Edee Jianji Yang Jonathan A.Fan Department of Electrical Engineering Stanford UniversityStanfordCA 94305USA Department of Applied Physics Stanford UniversityStanfordCA 94305USA Universite Clermont Auvergne Institut PascalBP 10448F-63000 Clermont-FerrandFrance CNRS UMR 6602Institut PascalF-63177 AubiereFrance

Metasurfaces are ultrathin optical elements that are highly promising for constructing lightweight and compact optical *** their practical implementation,it is imperative to maximize the metasurface *** optimization provides a pathway for pushing the limits of metasurface efficiency;however,topology optimization methods have been limited to the design of microscale devices due to the extensive computational resources that are *** introduce a new strategy for optimizing large-area metasurfaces in a computationally efficient *** stitching together individually optimized sections of the metasurface,we can reduce the computational complexity of the optimization from high-polynomial to *** a proof of concept,we design and experimentally demonstrate large-area,high-numerical-aperture silicon metasurface lenses with focusing efficiencies exceeding 90%.These concepts can be generalized to the design of multifunctional,broadband diffractive optical devices and will enable the implementation of large-area,high-performance metasurfaces in practical optical systems.

关键词： topology optimization surface

A Comparison of the Solubilizing Potential of Some Aminopolycarboxylic Acids, Hortrilon^(█)and Fetrilon^(█)for Use in Phytoextraction

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Open Journal of Soil Science 2013年第4期3卷 182-190页

作者： Emmanuel Amoakwah Jerry Ampofo-Asiama Stijn Van Slycken david K.essumang Department of Soil Genesis Survey and ClassificationSoil Research InstituteKumasiGhana Department of Analytical Chemistry and Echo Chemistry Faculty of BioScience EngineeringGhent UniversityGentBelgium Department of Chemistry University of Cape CoastCape CoastGhana

Phytoextraction has been introduced as a new technology to clean up soils contaminated with heavy metals as the use of conventional methods to clean up the soil is very expensive and destructive to the ecosystem. However, using plants to clean up contaminated soils takes a considerable period before the contaminants are removed from the soil by the plants. This has necessitated the use of amendments to enhance phytoextraction in order to shorten the period of contaminants removal by plants. In view of this, a pot experiment was conducted to study the effect of various aminopolycarboxylic acids (EDTA, EDDS, NTA dry and NTA liquid) and two commercial fertilizers which are Hortrilon? and Fetrilon? on their ability to solubilize Cd and Zn in contaminated soils. It was observed that the inducing effect of EDTA on the solubility of Cd and Zn persisted throughout the experimental period. Initially, EDDS enhanced the solubility Cd and Zn, however, its effect dissipated with time. The application of both NTA dry (powder) and NTA liquid had a significant effect on the solubility of Zn as a result of the formation of Zn-NTA soluble complexes. Hortrilon? and Fetrilon? solubilized significant concentrations of both Cd and Zn with Hortrilon? having the greatest inducing effect on the solubility of Cd and Zn.

关键词： EDTA EDDS NTA Hortrilon^(█) Fetrilon^(█) Soil Amendments Phytoextraction

Spatial and Temporal Distribution of Polychlorinated Biphenyl Residues in Tropical Soils

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Open Journal of Applied Sciences 2016年第4期6卷 234-247页

作者： John K. Bentum david K. Dodoo Peter K. Kwakye david K. essumang George A. Adjei Department of Chemistry College of Agric & Natural Sciences University of Cape Coast Cape Coast Ghana University College of Agriculture and Environmental Studies Bunso Eastern Region Ghana

Polychlorinated biphenyls (PCBs) in tropical soil samples from the Central Region of Ghana, and their variation with the soil characteristics were assessed. The soil characteristics of seventy eight samples were first determined. The PCBs was extracted with (1:1) hexane:acetone mixture, and then the extract treated with concentrated H2SO4, 5% KMnO4 and copper. The extract was finally eluted from a silica gel column with hexane:dichloromethane (97:3 v/v), and the PCBs analyzed using a gas chromatograph equipped with 63Ni electron capture detector (GC-ECD model CP 3800). The composition of PCBs homologous in the soils followed the order: hexa-PCBs (31.89%) > penta- PCBs (23.98%) > tri-PCBs (18.47%) > tetra-PCBs (13.67%) > hepta-PCBs (11.99%). The PCB congener profile in the study area was PCB 28 > PCB 153 > PCB 138 > PCB 52 > PCB 101 > PCB 180 > PCB 118. The mean concentration of the PCB congeners (dry matter basis) was PCB 28, 2.27 ± 2.436;PCB 52, 1.84 ± 2.27;PCB 101, 2.17 ± 2.52 μg/kg;PCB 118, 0.83 ± 0.89 μg/kg;PCB 138, 0.99 + 0.91 μg/kg;PCB 153, 1.18 ± 1.11 μg/kg and PCB 180, 1.18 ± 1.19 μg/kg. The mean concentrations of ΣPCBs were 9.15 ± 0.52 μg/kg for the surface soils (0 - 10 cm), 7.55 ± 0.56 μg/kg and 7.82 ± 0.55 μg/kg for the 10 - 20 cm and 20 - 30 cm sub-surface soils respectively. Significant but weak correlations were observed between PCBs and the soil pH, moisture, and exchangeable base. The coefficient of determination for all significant correlations was between 6.6% and 18.75%.

关键词： Polychlorinated Biphenyls Soil Properties Principal Component Analysis Contamination

Double Burden of Malnutrition: Toxic Metals in Breast Milk May Limit the Amounts of Micronutrients Available to Infants through Breast Milk

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Food and Nutrition Sciences 2019年第3期10卷 298-314页

作者： Adolf kofi Awua Rose Boatin Theodosia Adom Edward Christian Brown-Appiah Akusika M. Diaba Dominic Datohe david Kwaku Bansa Cellular and Clinical Research Centre Radiological and Medical Sciences Research Institute of the Ghana Atomic Energy Commission Accra Ghana Nutrition Research Centre Radiological and Medical Sciences Research Institute of the Ghana Atomic Energy Commission Accra Ghana

Background: The amounts of micronutrients in the diets of infants, and the factors that influence them needs to be monitored at the population level in order to avert detrimental developmental defects that impose lifetime-limitations on an infant’s regulatory and defense systems. This study therefore, sought to evaluate if increasing levels of the toxic metals, Hg, Pb and Cd in breast milk will result in reducing amounts of the micronutrients Zn, Se and Cu in breast milk. Methods: Breast milk samples of 114 women living in two mining areas (57 women each) in Ghana, whose babies’ amounts of breast milk intake at three months postpartum, and amounts of toxic metals had previously been determined in a prospective study, were analyzed for micronutrients by a combination of acid and microwave digestion, and quantifications were by two different modes (hydrogen and helium) of Octapole Reaction System Inductively Coupled Plasma Mass Spectrometer (7500 ce. Agilent), equipped with an ASX-510 Auto-sampler (Cetac). Results: All the breast milk specimen collected contained detectable amounts of Cu, Zn, both at levels less than have been previously reported, and Se. For specimen that did not contain Pb the amount of Se ranged from about 110 to 245 ng/g of milk, however, as the amount of Pb increased, the corresponding highest detected amount of Se reduced steeply, resulting in a right-angle triangle-shaped scatter plot. Similar relationships were observed between other toxic metals and micronutrients studied. A curve fitting regression analysis showed significant quadratic and cubic relationships between the amounts of Hg and Se, as well as between Pb, As and Cu. Conclusion: The results clearly suggest a double burden of malnutrition in these mining areas, where high loads of maternal toxic metals in breast milk, related significantly with a progressive reduction in the amounts of the micronutrients Cu and Se in breast milk, potentially reducing in infants’ intake of these micro

关键词： Toxic Metals Micronutrients Breastmilk Mining Infant Nutrition

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基于图像分割的驾驶员分心行为识别研究

浙江科技学院学报 2020年第3期32卷 209-215页

作者：叶绿陈铖 Sugianto Sugianto Chido Natasha Muponda Agordzo George kofi Koi david Ernest 浙江科技学院信息与电子工程学院杭州310023 浙江科技学院机械与能源工程学院杭州310023

针对驾驶员分心行为对交通安全产生隐患的问题,提出一种结合图像分割与卷积神经网络的驾驶员分心行为检测方法。该方法通过使用图像分割处理后的驾驶员不同分心行为的图像对卷积网络结构模型进行训练,来减轻背景噪声的影响,以提高模型... 详细信息

针对驾驶员分心行为对交通安全产生隐患的问题,提出一种结合图像分割与卷积神经网络的驾驶员分心行为检测方法。该方法通过使用图像分割处理后的驾驶员不同分心行为的图像对卷积网络结构模型进行训练,来减轻背景噪声的影响,以提高模型的识别性能。试验中使用未经分割的图像与经过前景分割后图像分别训练卷积神经网络模型,用分割后图像训练的模型识别的准确率达到了93.84%,高于使用原图像训练的模型。试验结果表明,结合图像分割和深度学习的驾驶员分心行为检测方法对驾驶员的分心行为有较好的检测效果。

关键词：图像分割神经网络特征提取分心行为识别

Study on the mechanism of JiChuanJian in the treatment of slow-transmission constipation based on network pharmacology

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Drug Combination Therapy 2023年第1期5卷 27-34页

作者： Hai-Zhao Liu Lu Han Yu-Tong Jin Yi-Yang Wang Joseph kofi Abankwah Xue-Tao Dong Chen Xu Yu-Hong Bian School of Intergrative Medicine Tianjin University of Traditional Chinese MedicineTianjin 301617China Department of Colorectal Surgery Tianjin Union Medical CenterTianjin 300121China

Background:Slow-transit constipation remains a functional colonic disorder with the most common gastrointestinal *** JiChuanJian(JCJ)is used for treatment,little is known about its mechanism of *** aimed to investigate the mechanism of JCJ in treating slow-transmission constipation based on network ***:The chemical components and action targets of the six herbs of JCJ were retrieved from the Traditional Chinese Medicine Systematic Pharmacology Analysis *** targets of the chemical components were obtained from the UniProt database,whiles the disease targets were retrieved from the Gene Cards database,Disgenet,and TTD databases.A Wayne diagram was drawn and the intersected targets were imported onto the STRING website for analysis to construct protein-protein interaction target *** Cytoscape software constructed protein-protein interaction to identify core targets and drug-active component-target interaction *** Kyoto Encyclopedia of Genes and Genomes and gene ontology enrichment analyses were performed through the david analysis ***:A total of 55 potential drug-active components of JCJ,233 drug-active ingredient targets,3215 slow-transmission constipation-related targets,and 176 drug and disease targets were *** core drug-active ingredients included quercetin,beta-sitosterol,stigmasterol,kaempferol and *** enrichment analysis in david database,we obtained 236 biological processes,31 cellular components and 41 molecular functions,mainly involving serotonin binding,G-protein coupled serotonin receptor activity,and neurotransmitter receptor activity,were identified.118 pathway enrichment results were obtained after the Kyoto Encyclopedia of Genes and Genomes pathway enrichment ***,we hypothesized that the active components in JCJ,such as quercetin,β-sitosterol,and stigmasterol,may treat slow transit constipation by regulating the serotonergic synaps

关键词： JiChuanJian slow-transmission constipation network pharmacology