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Assessment of the Wind Energy Potential of Two Burundian Sites

Energy and Power Engineering 2022年第5期14卷 181-200页

作者： Mathias Bashahu Pierre Nsabimana Juvenal Barakamfitiye fidele niyukuri Department of Physics and Technology University of Burundi Bujumbura Burundi Department of Mathematics Institute of Applied Pedagogy University of Burundi Bujumbura Burundi

1-year hourly wind speed data from two Burundian stations, namely Bujumbura and Muyinga, have been processed in this work to bring an efficient help for the planning and installation of wind energy conversion systems (WECS) at those localities. Mean seasonal and diurnal variations of wind direction and wind shear exponent have been derived. Two-parameter Weibull probability density functions (PDFs) fitting the observed monthly and annual wind speed relative frequency distributions have been implemented. As shown through three complementary statistical tests, the fitting technique was very satisfactory. A wind resource analysis at 10 m above ground level (AGL) has led to a mean power density at Bujumbura which is almost thirteen fold higher than at Muyinga. The use of the empirical power law to extrapolate wind characteristics at heights from 150 to 350 m AGL has shown that energy potential of hilltops around Muyinga was only suitable for small, individual scale wind energy applications. At the opposite, wind energy potential of ridge-tops and hilltops around Bujumbura has been found suitable for medium and large scale electricity production. For that locality and at those heights, energy outputs and capacity factors (CF or Cf) have been computed for ten selected wind turbines (WTs), together with costs of electricity (COE) using the present value of cost (PVC) method. Amongst those WTs, YDF-1500-87 and S95-2.1 MW have emerged as the best options for installation owing to their highest CF and lowest COE. Moreover, an analysis of those two quantities at monthly basis for YDF-1500-87 WT has led to its best performance in the dry season. Compared to the average present COE of household hydroelectricity consumption, results of this study have evidenced economical feasibility and benefit of WECS setting in selected Burundian sites in order to supplement traditional electricity sources.

关键词： Wind Shear Exponent Two-Parameter Weibull PDFs Statistical Tests Wind Energy Potential WT’s Energy Output and Capacity Factor Cost of Electricity Two Burundian Sites

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Cost-Effective Monitoring of the Fuel Air Equivalence-Ratio with a Lambda Sensor and a Microcontroller in a Downdraft Biomass Gasifier

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Open Journal of Applied Sciences 2024年第2期14卷 545-560页

作者： Jean fidele Nzihou Salou Hamidou Ousmane Zoundi Frederic Ouattara Bila Gerard Segda Formation and Research Unit in Sciences and Technologies University Norbert ZONGO Koudougou Burkina-Faso

The operation of biomass treatment devices such as gasifiers is based on the control of key parameters that play an important role in product formation. These include: temperature, excess oxygen, relative humidity and biomass composition. This work focuses on excess oxygen and temperature. Unfortunately, flue gas oxygen analyzers are expensive and not accessible to small industries. However, the equivalence ratio is linked to excess oxygen and has the advantage of not depending on biomass composition. This study therefore focuses on the design and development of a device for controlling this equivalence ratio by measuring oxygen concentration using a self-propelled Lambda probe, and a system for monitoring this equivalence ratio using an Arduino Uno 3 microcontroller. The temperature is recorded with an accuracy of ±1.5°C. For a heating time of 10 minutes, the response time to temperature change is around 3 seconds, which is sufficient for the device to function properly. This simple device is an efficient and cost-effective means of checking the equivalence ratio.

关键词： Equivalence Ratio Biomass Gasification Lambda Sensor Microcontroller C++

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Relationship between Inter Canine Width and Inter Alar Width, Inter Commissural Width, and Inter Canthal Distance: A Pilot Study

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Open Journal of Stomatology 2024年第6期14卷 279-290页

作者： Grevisse Bindele Ndombolo Augustin Mantshumba Milolo fidele Nyimi Bushabu Em Kalala Kazadi Pierrot Kumpanya Ntumba Jean Marie Kayembe Bukama Elias Lubadi Tshilumba Jean Paul Sekele Isouradi Department of Prosthodontics Teaching Hospital of Kinshasa University Kinshasa Democratic Republic of the Congo National Center of Research in Dental Sciences Kinshasa Democratic Republic of the Congo Department of Oral and Maxillofacial Surgery Teaching Hospital of Kinshasa University Kinshasa Democratic Republic of the Congo Department of Periodontology Teaching Hospital of Kinshasa University Kinshasa Democratic Republic of the Congo Department of Operative Dentistry Teaching Hospital of Kinshasa University Kinshasa Democratic Republic of the Congo

The aim of this study was to determine the relationship between inter canine width (ICW) and inter alar width (IAW), inter commissural width (ICoW), and inter canthal distance (ICaD) in Bantu population. Materials and Methods: It was a pilot study included all participants who were aged at least 18 years, without a history of orthodontics treatment from Prosthodontics Department, Faculty of Dental Medicine, University of Kinshasa. The Ethics committee of the National Center of Research for Dental Sciences in DR Congo approved the study protocol (CNRSB 1504.218). The participants medical records were obtained from the interview and dental examination. Nature of the study was explained with participant information sheet, and an informed consent of all participants was obtained. The inclusion criteria were no missing maxillary and mandibular teeth, no diastema, and no anterior restorations, 18 years old before enrollment in the study. The exclusion criteria were inability to meet the above requirements, pregnancy, and refusal to participate in the study. The inter-canine width (ICW), inter alar width (IAW), inter canthal distance (ICaD) and inter-commissural width (ICoW) of each participant were measured with a digital Vernier caliper (Mitutoyo, UK Ltd.,) (0.01 mm) three times and the average value was recorded. The inter canthal distance (ICaD) was measured without applying pressure by bringing the recording parts of the caliper just in contact with the medial angle. The inter alar width (IAW) was marked with a fine marked pencil on the widest outer surface of the alae of the nose on either side or width. Those two points were measured without applying pressure by bringing the recording parts of the caliper just in contact with the outer surface. The participant was told to stop breathing shortly to avoid any change in shape of the nose. The inter-commissural width (ICoW) was determined by measuring the maxillary lip vermilion from commissure to commissure without the

关键词： Relationship Inter-Canine Width Inter Alar Width Inter Canthal Distance Inter Commissural Width

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Evaluation of Hemostatic and Antihemolytic Effects of Aqueous Extract of Garcinia kola (Clusiaceae) Fresh Seeds

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Journal of Biosciences and Medicines 2022年第4期10卷 205-218页

作者： Kpahe Ziéhi fidele Bleu Gomé Michèle Ackah Jacques Auguste Laboratory of Biodiversity and Tropical Ecology Jean Lorougnon Guédé University Daloa Cote d’Ivoire Laboratory of Agrovalorization Jean Lorougnon Guédé University Daloa Cote d’Ivoire

Objectives: Garcinia kola seeds (EAgk) (Clusiaceae) contain coagulant components use to pretreat aquaculture wastewater in Nigeria. This work was undertaken to assess the effects of EAgk on blood coagulation because of its contents. Methods: Five groups of four rats of both sexes (200 ± 5 g) received orally distilled water, phytomenadione (15 mg/kg b.w.) and garcinia kola seeds extract (250, 500 and 1000 mg/kg b.w.) for four days and after this period, bleeding time was measured by tail hemorrhage model. Activated partial thromboplastin time (aPTT) and platelet count were determined by coagulometer and hematological analyzer respectively. Blood red cells protection of EAgk was measured by the methods of 2,2’-Azobis(2-methylpropionamidine) dihydrochloride (AAPH)-induced hemolysis and inhibition of 2,2-Diphenyl-1-picryl hydrazyl (DPPH) radical and hydrogen peroxide. Results: EAgk at 1000 mg/kg b.w. induced a significant decrease in bleeding time from 420 ± 27.3 s to 157.5 ± 18.9 s. The platelet count of group of rat treated with EAgk (1000 mg/kg b.w.) increased significantly (p 0.05, n = 4). EAgk inhibited hemolysis, DPPH radical and hydrogen peroxide with IC50 values of 1.02 ± 0.2;3.2 × 10?2 ± 0.12 and 1.01 ± 0.5 mg/mg respectively. Conclusions: EAgk exhibits hemostatic effects, which could justify the presence of coagulant components in the extract. Erythrocytes’ protective activity of Garcinia kola seeds may be due to free radicals and hydrogen peroxide inhibition.

关键词： Garcinia kola Hemostatic Antihemolytic Bleeding Time Platelet

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Spatio-temporal variation of soil moisture in a fixed dune at the southern edge of the Gurbantunggut Desert in Xinjiang, China

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Journal of Arid Land 2019年第5期11卷 685-700页

作者： ZHU Hai HU Shunjun YANG Jingsong fidele KARAMAGE LI Hao FUSihua State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Akesu National Station of Observation and Research for Oasis Agro-ecosystem Aksu 843017China Nanjing Institute of Geography and Limnology Chinese Academy of SciencesNanjing 210008China

Soil moisture is critical for vegetation growth in ***,detailed data regarding the soil moisture distribution in space and time in the Gurbantunggut Desert of China have not yet been *** this study,we conducted a series of in situ observation experiments in a fixed sand dune at the southern edge of the Gurbantunggut Desert from February 2014 to October 2016,to explore the spatio-temporal variation of soil moisture content,investigate the impact of Haloxylon ammodendron(***.)Bungeon soil moisture content in its root zone,and examine the factors influencing the soil moisture spatial ***-way analysis of variance,least significant difference tests and correlation analysis were used to analyze the *** results revealed that the soil moisture content exhibited annual periodicity and the temporal variation of soil moisture content throughout a year could be divided into three periods,namely,a moisturegaining period,a moisture-losing period and a moisture-stable *** to the temporal and spatial variability,the 0–400 cm soil profile could be divided into two layers:an active layer with moderate variability and a stable layer with weak *** temporal variability was larger than the spatial variability in the active layer,and the mean profile soil moisture content at different slope positions displayed the trend of decreasing with increasing relative height and mainly followed the order of interdune area>west and east slopes>slope *** mean profile soil moisture content in the root zone of dead *** individuals was significantly higher than that in the root zones of adult and young individuals,while the soil moisture content in the root zone of adult individuals was slightly higher than that in the root zone of young individuals with no significant *** spatial pattern of soil moisture was attributable to the combined effects of snowfall,vegetation and soil texture,whereas the effects of rainfall a

关键词： fixed sand dune soil moisture root zone Haloxylon ammodendron Gurbantunggut Desert

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Relationships between soil seed banks and above-ground vegetation along a disturbance gradient in the W National Park trans-boundary biosphere reserve,West Africa

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Journal of Plant Ecology 2017年第2期10卷 349-363页

作者： Patrice Savadogo Lassina Sanou SDjibril Dayamba fidele Bognounou Adjima Thiombiano World Agroforestry Centre and International Crop Research Institute for the Semi-Arid Tropics(ICRAF-ICRISAT) West and Central Africa Region-Sahel NodeBP 12404 NiameyNiger Centre National de la Recherche Scientifique et Technologique INERADépartement Productions Forestières03 BP 7047Ouagadougou 03BurkinaFaso Unitéde Formation et de Recherche en Sciences de la Vie et de la Terre/Laboratoire de Biologie et Ecologie Végétales(UFR/SVT) Universitéde Ouagadougou03 BP 7047Ouagadougou 03BurkinaFaso World Agroforestry Centre(ICRAF) West and Central Africa Regional Office-Sahel NodeBP E5118 BamakoMali Département des Sciences Biologiques Université´du QuébecàMontréal2080 rue Saint Urbain8888Montréal QC H3C 3P8Canada

Aims Vegetation succession depends on the availability of suitable prop-agules in the soils,thus knowledge of soil seed banks is essential for formulating effective strategies for restoring the vegetation of degraded *** W National Park,the only trans-boundary bio-sphere reserve in West Africa,is being extensively fragmented and degraded in recent *** aims of this study were to assess the reserve’s soil seed banks,their relationships with standing veg-etation and bundle of disturbances and their potential significance for vegetation *** The size and composition of the above-ground species vegetation were assessed in nine plots of 1 ha each representing a range of habitats with differing disturbance severity(low,intermediate and high).A total of 702 soil samples were taken from three layers(0-3,3-6 and 6-9 cm)and soil seed bank was analyzed using the seed-ling emergence *** Findings Generally,seeds of non-woody taxa dominated in samples from all soil depths and habitats of all disturbance *** mean soil seed density was 17.8,24.4 and 26.3 seeds/dm^(3) in samples from the least,intermediate and most disturbed sites,respectively,and highest in the upper soil layers in all *** results indi-cate that there is limited potential for restoring woody vegetation solely from soil seed banks,and that woody species in the region rely more on recently shed seeds trapped in the standing dead biomass and litter on the ground than soil seed banks for ***,human intervention is needed to accelerate forest recovery,mainly through alleviating anthropogenic impacts on the ecosystem(for instance,avoiding destruction of new seeds by intense fire),and site manipulation to improve environmen-tal conditions for seedling establishment and *** ways of restoring forests than through the soil seed bank(*** seeds collected elsewhere,and planting tree seedlings)could also be relevant.

关键词： disturbance savanna-woodland restoration regeneration seed bank vegetation degradation West Africa

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Hypolipidemic,antioxidant and anti-atherosclerogenic effects of aqueous extract of Zanthoxylum heitzii stem bark in diet-induced hypercholesterolemic rats

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Asian Pacific Journal of Tropical Medicine 2015年第5期8卷 359-365页

作者： fidele Ntchapda Kakesse Maguirgue Hamadjida Adjia Paul Faustin Seke Etet Théophile Dimo Department of Biological Sciences Faculty of ScienceUniversity of Ngaoundéré Department of neuroscience Faculty of Medicine.University of Montreal Department of Basic Health Sciences College of Applied Medical SciencesQassim University Department of Animal Biology and Physiology Faculty of ScienceUniversity of Yaoundé

Objective:To evaluate anti-dyslipidemic,antioxidant and anti-atherosclerogenic properties of this extract in diet-induced hypercholesterolemic rat.a model of metabolic syndrome-induced atherosclerosis and associated cardiovascular ***:Normocholeslerolemic(NC) male rats were divided into six groups(n=10) and fed a high-cholesterol(HC) diet for 30 days(5 groups),or normal rat chow(normal control group).Rats given a HC diet also received distilled water(disease control),the potent hypocholcsterolcmic agent with antiatherosclerotic activity atorvastatin(2 mg/kg,positive control),or one of the three doses of Zanthoxylum heitzii stem bark aqueous extract tested(225,300 and 375 mg/kg) concomitantly for four *** of general toxicity,body temperature and weight,and water and food intake were monitored in live *** sacrifice,lipid profiles and oxidative stress markers were assessed in the blood and liver,aorta,and feces,and histopathological analysis of aorta was ***:Plant extract prevented the elevation of aortic total cholesterol and triglycerides,and hepatic low density lipoprotein,very low density lipoprotein,and total *** peroxidation(TBARS) was decreased and aortic atherosclerotic plaque formation ***:These observations strongly suggest that stem bark aqueous extract of Zanthoxylum heitzii has anti-atherosclerogenic properties,at least partly mediated by antioxidant and hypolipidemic effects.

关键词： Zanthoxylum heitzii Plant extract Antioxidant Anti-atherosclerogenic Hypocholesterolemic Hypolipidemic

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Natural Products as Potential Lead Compounds for Drug Discovery Against SARS-CoV-2

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Natural Products and Bioprospecting 2021年第6期11卷 611-628页

作者： Oyere Tanyi Ebob Smith B.Babiaka fidele Ntie-Kang Department of Chemistry Faculty of ScienceUniversity of BueaP.O.Box 63BueaCameroon Institute for Pharmacy Martin-Luther-Universität Halle-WittenbergKurt-Mothes-Str.306120 Halle(Saale)Germany

For the past 2 years,the coronavirus responsible for the COVID-19 infection has become a world pandemic,ruining the lives and economies of several nations in the *** has scaled up research on the virus and the resulting infection with the goal of developing new vaccines and *** products are known to be a rich source of lead compounds for drug discovery,including against infectious diseases caused by microbes(viruses,bacteria and fungi).In this review article,we conducted a literature survey aimed at identifying natural products with inhibitory concentrations against the coronaviruses or their target proteins,which lie below 10μ*** led to the identification of 42 compounds belonging to the alkaloid,flavonoid,terpenoid,phenolic,xanthone and saponin *** cut off concentration of 10μM was to limit the study to the most potent chemical entities,which could be developed into therapies against the viral infection to make a contribution towards limiting the spread of the disease.

关键词： Antivirals Drug discovery Inhibitors Lead compounds Natural products SARS-CoV-2

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Correlation between the Bizygomatic Distance and the Width of the Upper Central Incisor in the Cameroonian Melanoderma Adult

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Open Journal of Stomatology 2022年第10期12卷 294-304页

作者： Achoundong Makeumo Ericka Flavie Kumpanya Ntumba Pierrot Njajou Omer Agbor Michael Sekele Isouradi Bourley Jean Paul Nyimi Bushabu fidele Faculty of Dental Surgery University of the Mountains Bangangte Cameroon Department of Prosthodontics and Orthodontics Faculty of Dental Medicine University of Kinshasa Kinshasa Democratic Republic of the Congo Department of Oral and Maxilla-Facial Surgery Service of Oral Maxillofacial-Head and Neck Oncology Surgery Faculty of Dental Medicine University of Kinshasa Kinshasa Democratic Republic of the Congo

Bizygomatic distance is a relevant reference used to assist and to guide the choice of antero superior prosthetic teeth, especially when no information about the natural teeth was available. The aim of the present paper was to determine the distance between the canine tips from a bizygomatic distance and to estimate the width of the upper central incisor in normal-dental-facial indices of Cameroonians. Materials and methods: A cross-sectional study of 900 normal Cameroonians of both sexes was conducted. Measurements of bizygomatic distance, distance between the two upper pointers and the mesio-distal width of the upper central incisor were made with a manual and a digital caliper respectively. The equation for calculating the distance of higher canine pointers from the bizygomatic distance was DCT = 0.081 (BZD) + 26.201. The width prediction of the central incisor was obtained by the following formula: WUCI = 6.252 + 0.019 (BZD) + 0.035(DCT) + 0.062 (Reg cul) + (?0.479) sex. *** represents the cultural region of origin. Results: Female sex was represented by 56.6% against 43.30% males. The average age was 37± (32 SD) years. The average value of the bizygomatic distance was 130.23 mm, the width of the upper central incisor was 9.39 mm while the distance between the two upper canine pointers was 36.70 mm. Significant correlations between bizygomatic distance, the distance between the two canine pointers, and the width of the upper central incisor were found (P = 0.000). Conclusion: The width of the central incisor and the distance between the two upper canine pointers may be determined by the non-invasively method of the bizygomatic distance in the perspective of choosing the teeth for dental prosthesis.

关键词： Bizygomatic Distance Dental Prosthesis Cameroonian Melanoderma Facial Indices

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Compounds from African Medicinal Plants with Activities Against Selected Parasitic Diseases:Schistosomiasis,Trypanosomiasis and Leishmaniasis

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Natural Products and Bioprospecting 2018年第3期8卷 151-169页

作者： Conrad V.Simoben fidele Ntie-Kang Sergi H.Akone Wolfgang Sippl Institute of Pharmacy Martin-Luther University of Halle-WittenbergWolfgang-Langenbeck-Str.406120 Halle(Saale)Germany Department of Chemistry Faculty of ScienceUniversity of BueaP.O.Box 63Buea 00237Cameroon Institute of Pharmaceutical Biology and Biotechnology Heinrich-Heine-UniversityUniversitaetsstrasse1Geb.26.23Duesseldorf 40225Germany Department of Chemistry Faculty of ScienceUniversity of DoualaPO Box 24157Douala 00237Cameroon

Parasitic diseases continue to represent a threat on a global scale,particularly among the poorest countries in the *** is particularly because of the absence of vaccines,and in some cases,resistance against available drugs,currently being used for their *** this review emphasis is laid on natural products and scaffolds from African medicinal plants(AMPs)for lead drug discovery and possible further development of drugs for the treatment of parasitic *** the discussion,emphasis has been laid on alkaloids,terpenoids,quinones,flavonoids and narrower compound classes of compounds with micromolar range activities against Schistosoma,Trypanosoma and Leishmania *** each subparagraph,emphasis is laid on the compound subclasses with most promising in vitro and/or in vivo activities of plant extracts and isolated *** for future drug development from African medicinal plants have also been *** review covering 167 references,including 82 compounds,provides information published within two decades(1997-2017).

关键词： African medicinal plants Leishmaniasis Natural products Parasitic diseases Schistosomiasis Trypanosomiasis

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