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Partial Purification and Characterization of Cellulase Produced by <i>Bacillus sphaericus</i>CE-3

Advances in Microbiology 2017年第4期7卷 293-303页

作者： Chito Clare Ekwealor fredrick John Chidi Odibo Chukwudi Ogbonnaya Onwosi Department of Applied Microbiology & Brewing Nnamdi Azikiwe University Awka Nigeria Department of Microbiology University of Nigeria Nsukka Nigeria

Cellulase is an enzyme produced by fungi, bacteria, protozoa and termite, that hydrolyze cellulose. They are known for their diverse applications in industry and medicine. The aim of this study is to purify and investigate cellulolytic properties of cellulase enzyme produced by Bacillus sphaericus CE-3 isolated from refuse dump in Nnamdi Azikiwe University, Awka, Nigeria. Enzyme was produced by submerged fermentation at 30°C for 30 h. The enzyme was purified to homogeneity by dialysis in 4M sucrose solution, ion-exchange chromatography on Q-Sepharose FF and by hydrophobic interaction chromatography on Phenyl Sepharose CL-4B. The relative molecular mass of the enzyme was estimated using SDS-Polyacrylamide gel electrophoresis. Effects of temperature, pH and metals on enzyme activity and stability and the relative rate of hydrolysis of various substrates were also studied. The Purification fold for the enzyme was 7.8, with 66.4 μ/mg specific activity protein and overall yield of 35.8. The relative molecular mass range of the enzyme was estimated between 22.3 kDa - 26.3 kDa. The enzyme was optimally active at pH 9.0 and 40°C, stable at pH 9.0 and unusually retained over 90% activity between 50°C - 100°C after 30 min incubation. It was strongly activated by Mn2+ but inhibited by Ba2+, Co2+, Hg2+, Pb2+, Cu2+, Sr2+, Fe2+, Ca2+ and Zn2+. The cellulase displayed high catalytic activity with untreated sawdust, followed by carboxymethyl cellulose, while sodium hydroxide treated sawdust was the least hydrolyzed. Since the enzyme is thermo-stable, alkalophilic and could utilize natural wastes like sawdust as substrate, it is obvious that it would be of great use in textile, starch processing and pulp and paper industries.

关键词： Cellulase Bacillus sphaericus CE-3 Untreated Sawdust Catalytic Activity

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Influence of Human Resource Needs on Adoption of Forest Innovations in Kenya

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Open Journal of Forestry 2016年第5期6卷 460-475页

作者： Michael O. Mukolwe Gilbert O. Obwoyere fredrick U. Ngesa Kenya Forestry Research Institute Nairobi Kenya Department of Natural Resources Egerton University Egerton Kenya Department of Agricultural Education and Extension Egerton University Egerton Kenya

A combination of factors, including inadequate interactive influence of professional human resource needs, contributes to low adoption of forest innovations. This study was conducted to assess the influence of quantity of professional human resource needs on adoption of forest innovations across relevant institutions in Kenya. The study considered 51 main institutions involved in, or support conservation activities, of which 33 were public, 14 non-governmental, and 4 private. Purposive sampling was used due to the heterogeneity of the institutions involved in conservation. Primary data were collected using a structured questionnaire. A quartile graph-based quantitative model was used to establish the differences in capacity variation expressed as expected variation region or the common cause and the unexpected variation region or the special cause. The latter should be investigated and acted upon. Statistical analysis involved Levene’s Test of Equality of Variances. Embracing both approaches confirmed the model as an appropriate quantitative analytical framework for assessing and articulating elements of institutional capacity, and that quantity of professional human capital (P < 0.05) is key to influencing adoption of forest innovations in Kenya. The study reiterates that to overcome professional capacity gaps and respond to conservation paradigm shift, quantity was relevant and was an imperative policy issue.

关键词： Professional Human Resource Institutional Capacity Adoption Forest Innovations

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Lay perceptions of breast cancer in Western Kenya

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World Journal of Clinical Oncology 2015年第5期6卷 147-155页

作者： Violet Naanyu Chite fredrick Asirwa Juddy Wachira Naftali Busakhala Job Kisuya Grieven Otieno Alfred Keter Anne Mwangi Orango Elkanah Omenge Thomas Inui Academic Model Providing Access to Healthcare (AMPATH) Department of Behavioral Sciences School of MedicineCollege of Health SciencesMoi University Department of Medicine School of MedicineIndiana University Department of Pharmacology School of MedicineCollege of Health SciencesMoi University Department of Reproductive Health School of MedicineCollege of Health SciencesMoi University Regenstrief Institute Inc.

AIM: To explore lay perceptions of causes, severity, presenting symptoms and treatment of breast cancer. METHODS: In October-November 2012, we recruited men and women(18 years and older) from households and health facilities in three different parts of Western Kenya, chosen for variations in their documented burdens of breast cancer. A standardized and validated tool,the breast cancer awareness measure(BCAM), was administered in face-to-face interviews. Survey domains covered included socio-demographics, opinions about causes, symptoms, severity, and treatment of breast cancer. Descriptive analyses were done on quantitative data while open-ended answers were coded, and emerging themes were integrated into larger categories in a qualitative analysis. The open-ended questions had been added to the standard BCAM for the purposes of learning as much as the investigators could about underlying lay beliefs and perceptions. RESULTS: Most respondents were female, middle-aged(mean age 36.9 years), married, and poorly educated. Misconceptions and lack of knowledge about causes of breast cancer were reported. The following(in order of higher to lower prevalence) were cited as potential causes of the condition: Genetic factors or heredity(n = 193, 12.3%); types of food consumed(n = 187, 11.9%); witchcraft and curses(n = 108, 6.9%); some family planning methods(n = 56, 3.6%); and use of alcohol and tobacco(n = 46, 2.9%). When asked what they thought of breast cancer's severity, the most popular response was "it is a killer disease"(n = 266, 19.7%) a lethal condition about which little or nothing can be done. While opinions about presenting symptoms and signs of breast cancer were able to be elicited, such as an increase in breast size and painful breasts, earlystage symptoms and signs were not widely recognized. Some respondents(14%) were ignorant of available treatment altogether while others felt breast cancer treatment is both dangerous and expensive. A minority reported alte

关键词： Breast cancer Health education Cancer control Lay health beliefs

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The Effect of Industrial Effluents on the Quality of Onukpawahe Stream, Tema-Ghana

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Journal of Environmental Science and Engineering(B) 2016年第10期5卷 457-475页

作者： Abdalla Abubakari Anyemedu fredrick Oppong-Kyekyeku Donkor Emmanuel Jackson Adiyiah Nyantakyi Environmental Protection Agency (EPA) Accra M326 Ghana Department of Civil Engineering Kwame Nkrumah University of Science and Technology PMB Kumasi Ghana Environmental Protection Agency (EPA) Sunyani 1505 Brong-Ahafo Ghana

Industrial effluents discharged into surface water body present a high percent of pollution in Ghanaian streams and rivers. The current study assessed the effects of industrial effluent on the quality of Onukpawahe stream which receives industrial effluents from the Tema Metropolis. Effluent samples were collected from six （6） selected industries and the water samples were collected from sixteen （16） different locations on the Onukpawahe stream. Various physico-chemical parameters such as BOD, TDS, Conductivity, COD, pH, TSS, Turbidity, Temperature, Colour, Sulphate, Phosphate, Ammonia and Nitrate were analysed during the current investigation. The average values of all the physico-chemical parameters （except pH and DO） were all above the EPA sector specific effluent guidelines. It was established in the study that the industries have polluted the stream and have grievously compromised the quality of the Onukpawahe stream. The surface water and industrial effluent must be monitored by the authorities in order to prevent further degradation of the river quality.

关键词： Onukpawahe stream industrial effluent water quality physico-chemical parameters EPA limits.

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Economic Growth, Governance and CO2 Emissions in West Africa

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Chinese Journal of Urban and Environmental Studies 2023年第1期11卷 27-48页

作者： Innocent IFELUNINI Ugochinyere EKPO S.Adzugbele AGBUTUN O.Winnie ARAZU C.Samuel UGWU Nnabuike OSADEBE O.fredrick ASOGWA Department of Economics/Resource & Environmental Policy Research Centre University of Nigeria Department of Economics University of Nigeria Department of Public Administration and Local Government University of Nigeria Department of Sociology and Anthropology University of Nigeria

Despite being the regions with the least levels of carbon emissions in the world, African countries are facing unique challenges on climate change, increased carbon emission levels and the need for environmental governance improvement. This study, therefore, examined the implications of economic growth and governance on CO2emissions in West Africa. Specifically, the study investigated the role of governance in moderating the effect of economic growth on CO2emissions in West Africa. The study utilized data for 16 West African countries from 2000 to 2020 in an unbalanced panel data framework. Empirical analyses were conducted using the Instrumental Variable Fixed Effects estimator with Driscoll and Kraay Standard Errors, as well as the Instrumental Variable Quantile Regression in order to account for serial correlation, endogeneity and conditional heteroskedasticity. The following conclusions were drawn from the results. First,economic growth significantly increases CO2emissions in the region with the Environmental Kuznet Curve hypothesis present. Second, the quantile regression estimates reveal that the effect of economic growth on CO2emissions is higher in countries where the initial level of carbon emissions is considerably high. Third, the results further show that in the presence of improved governance quality, economic growth does not significantly influence CO2emissions in the region. Fourth, political stability and regulatory quality were the only indicators of governance that significantly impacted environmental pollution in the region. Finally, we found that other factors such as trade, urbanization, and renewable energy also significantly influenced CO2emissions in the region. The study concludes by highlighting the importance of governance in moderating the effect of economic growth on CO2emissions, as well as the importance of heterogeneous analysis for understanding the dynamism in economic relationships.

关键词： Economic growth governance CO 2 emissions environmental pollution West Africa

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中小型企业的创新与生产力：来自加纳的实证研究

中小型企业的创新与生产力：来自加纳的实证研究

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作者：弗雷德（fredrick Darimeh）首都经济贸易大学

学位级别：硕士

创新对于中小企业生产率的提升和国家的进步都有至关重要的作用。本文以世界银行网站对加纳的四个地区（阿克拉、北塔马莱、特马和塔莫拉迪）的企业调查数据为样本,对创新与生产力的关系展开研究。研究结果表明,创新对加纳中小企业的运... 详细信息

创新对于中小企业生产率的提升和国家的进步都有至关重要的作用。本文以世界银行网站对加纳的四个地区（阿克拉、北塔马莱、特马和塔莫拉迪）的企业调查数据为样本,对创新与生产力的关系展开研究。研究结果表明,创新对加纳中小企业的运营存在正向影响。这进一步证实了具有创新能力的中小企业更容易获得竞争优势的结论。同时,本文对中小企业创新性的影响因素提出不同见解。以前学者的研究指出,大企业比小企业更具创新性。但本文的研究发现,在其他条件不变的情况下,随着企业规模的增长,额外花销将会增加,导致创新产出水平下降。大型企业拥有更多运营资金,却未必具有创新的动力;相反,拥有技术知识、运营效率和竞争压力的小公司更具有创新性。此外,企业规模对生产力水平存在影响作用,这对企业竞争战略的制定至关重要。创新对中小企业生产率水平存在正向影响。但由于中等收入国家与发达国家创新驱动因素的差异,特别是在知识能力、信息、通信技术和环境特征的不同导致对发达国家中小企业创新和生产率关系的研究结果在中等收入国家中并不适用。

关键词：创新生产率中小型企业中等收入

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Nmp4促进TNF-α诱导的成骨细胞凋亡

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中国生物化学与分子生物学报 2010年第9期26卷 828-835页

作者：杨周岐 fredrick M.PAVALKO 商澎空间生物实验模拟技术重点实验室西北工业大学生命学院特殊环境生物物理学研究所西安710072 美国印第安纳大学医学院细胞与整体生理学系印第安纳波利斯in46202

核基质蛋白4(nuclear matrix protein4,Nmp4)是一种具有核质穿梭功能的结构性转录因子.主要通过负调控调节成骨细胞分化和增殖,抑制骨密度及骨量增加,而Nmp4是否调节成骨细胞凋亡,还未有相关报道.本课题通过分离Nmp4基因敲除(Nmp4-KO)... 详细信息

核基质蛋白4(nuclear matrix protein4,Nmp4)是一种具有核质穿梭功能的结构性转录因子.主要通过负调控调节成骨细胞分化和增殖,抑制骨密度及骨量增加,而Nmp4是否调节成骨细胞凋亡,还未有相关报道.本课题通过分离Nmp4基因敲除(Nmp4-KO)和野生型(WT)小鼠原代成骨细胞,以肿瘤坏死因子(TNF-α)为凋亡诱导手段,研究了Nmp4对成骨细胞凋亡的影响及其作用机制.体外细胞实验发现,Nmp4-KO显著抑制TNF-α诱导的成骨细胞内caspase-3激活.Nmp4-KO促进细胞外信号调节激酶(Erk)和丝氨酸/苏氨酸蛋白激酶(Akt)信号途径的激活,抑制c-Jun氨基末端激酶(JNK)磷酸化,从而对抗成骨细胞凋亡.TNF-α诱导处理可增强成骨细胞核因子NFκB磷酸化及其核转位,但Nmp4基因缺失无进一步促进作用.未经诱导处理的Nmp4-KO细胞内NFκB磷酸化水平显著高于WT对照.此外,TNF-α诱导处理促使线粒体途径信号分子Bad磷酸化及Bcl-xl表达水平适当升高,但在两种细胞表型间无显著差异.这些结果证实,Nmp4基因敲除可促进相关抗凋亡信号分子的激活和表达,抑制促凋亡信号的激活,进而抑制成骨细胞凋亡的发生.

关键词：核基质蛋白4 成骨细胞凋亡肿瘤坏死因子α

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The Impact of the Ghana＇s Oil Discovery on Land Investment and Its Implications in the People, Agriculture and the Environment （Case Study： Cape Three Points, Ghana）

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Journal of Environmental Science and Engineering(B) 2012年第7期1卷 922-930页

作者： Peter Paa-Kofi Yalley Chris Atanga Joe fredrick Cobbinah Philip Kwaw Design and Technology Department University of Education Kumasi 233 32 Ghana Western Regional Land Commission Sekondi 233 31 Ghana Building Technology Department Takoradi Polytechnic Takoradi 233 31 Ghana Civil Engineering Department Takoradi Polytechnic Takoradi 233 31 Ghana

The study was conducted to assess the impact of Ghana＇s oil discovery on the land values, the extent of acquisition, and their implications of the land investment in the people, agriculture and the environment in the Cape Three Points area, which is the communities close to the oil field. Questionnaires were designed and administered to collect data from the chiefs, queen mothers, family heads and opinion leaders of the area. Results of the studies indicated that there had been an increase of about 2000% in land values from 2007 to 2011. Also there was an increase in demand for lands in the Cape Three Points with acquisitions usually ranging from 10 acres to over 600 acres. It also emerged that the livelihood of the inhabitants of Cape Three Points was threatened due to the conversion of arable land to non-agriculture uses. This change in land uses has significant negative impacts on land degradation and its related reduction of agricultural and food production in the area. The technical difficulties of assessing land degradation, the weakness of existing databases, and the poorly explored linkages between land degradation and other aspects of rural development were some of the limitation of the studies. The study increased awareness of the chiefs and other land owners to reserve land for the future generation and for agriculture purposes. The study drew government＇s attention through the Ahanta West District Assembly to the planning needs of the towns in the Cape Three Points to streamline land use of the area.

关键词： Cape Three Points oil agriculture land degradation.

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Application of Hydrazine Hydrate in the Synthesis of Octa(aminophenyl)silsesquioxane (OAPS) Poss

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Advances in Chemical Engineering and Science 2013年第1期3卷 93-97页

作者： Jacob Kiptanui Koech Qun Shao fredrick Nzioka Mutua Yimin Wang State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University Shanghai China

Octa(aminophenyl)silsesquioxane (OAPS) was prepared from octaphenyl silsesquioxane (OPS) in two steps, first nitration to obtain Octa(nitrophenyl)silsesquioxane (ONPS) then reduction by using the stable, inexpensive, and readily available hydrazine hydrate as the reducing agent in the presence of Iron(III)Chloride catalyst with a yield of around 87%. Hydrazine is a two-electron reducing agent whereas nitro group is a four-electron reduction process. The activated carbon serves as an adsorbent and electrical conductor enabling the reaction to occur by acting as a mediator between a two-electron reagent and a four-electron process. Adsorption provides a reducing potential and a supply of electrons from many hydrazines making possible the initial four-electron process even though each individual hydrazine is a two-electron donor. The product was characterized by FTIR and 1H NMR. The time period for preparation of ONPS from octaphenyl silsesquioxane was considerably shortened to avoid double nitration of the aromatic rings.

关键词： Octa(aminophenyl)silsesquioxane Octa(nitrophenyl)silsesquioxane Hydrazine Nanocomposite Iron(III)Chloride Reduction

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Processes Governing the Retention of Phosphorus and Nitrogen in Nyashishi Wetland

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Open Journal of Ecology 2014年第3期4卷 124-134页

作者： Baraka C. Sekadende John F. Machiwa fredrick F. Mwanuzi College of Engineering Science and Technology Dar es Salaam Tanzania Tanzania Fisheries Research Institute Kigoma Tanzania University of Dar es Salaam Dar es Salaam Tanzania

One of the important functions of the wetland is the retention of catchment nutrients and improving lacustrine water quality. This study analyzed how much nutrients were retained in the Nyashishi wetland, southern part of Lake Victoria, and went further to analyze the processes which were responsible in the reduction of nutrients. Three major processes were analysed in this study, namely nutrients uptake by three macrophyte species (Eichhornia crassipes, Cyperus papyrus and Typha domingensis) dominating the Nyashishi wetland, nitrification and denitrification processes. The study demonstrated high nutrients retention especially phosphorus nutrients of which up to 98% were retained. In some occasions, particularly for nitrogen nutrients, there was 0% retention especially during wet season. In some other instances, the inflow exceeded the outflow meaning that, more nutrients were generated by the wetland itself. Among the three processes analyzed, nutrients uptaken by macrophytes were more efficient in reducing nutrients in wetland water. Biological nitrification and denitrification which are believed to be the major pathway for ammonia removal in both natural and constructed wetlands were less important in this study. Among the macrophyte species, Eichhornia crassipes demonstrated higher uptake rate than the other two species possibly due to its high turnover rate. This ability can be exploited in removing excess nutrients from runoff by frequent harvesting of the mature plants.

关键词： Phosphorus Nitrogen Nitrification Denitrification Nutrients Uptake

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