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A Brief Review of How to Construct an Enzyme-Based H2O2Sensor Involved in Nanomaterials

Advances in Nanoparticles 2021年第1期10卷 1-25页

作者： Uwitonze nestor Hitimana Frodouard Muhizi Theoneste Department of Chemistry School of Science College of Science and Technology University of Rwanda Kigali Rwanda

This article briefly reviews how to construct an enzyme based hydrogen peroxide sensor involving nanomaterials, which has the advantages of high efficiency, good sensitivity and selectivity, fast response time and an extended range of linearity with lower detection limit. Glucose biosensor is constructed by immobilizing glucose oxidase enzyme on the polycarbonate membrane and the protective cover is then filled with a physiological phosphate buffer, pH 7.4. The novel blocking hydrophobic membrane which is only permeable to hydrogen peroxide is used to eliminate electrochemical interferences. This constructed enzyme based H2O2 biosensor is miniaturized by the involvement of nanomaterials like carbon nanotubes, platinum nanoparticles and silver nanoparticles and it can achieve the effective microscopic detection of glucose. The introduction of nanomaterials including some pure metals (Ag, Au, Pd, Ni, Pt, and Cu), metal oxide (ZnO and TiO2), bimetallic (Au/Ag and Au/Pt) and carbon (nanotubes and graphene) nanomaterials in the construction of the enzyme based H2O2 biosensor improves its sensitivity and performance by enhancing the enzymatic activity, and allows the introduction of many new signal transduction technologies in biosensors. This review article summarizes the working principles of glucose oxidase based hydrogen peroxide sensor, importance of involving nanomaterials in biosensor manufacturing, basic characteristics and components of a biosensor, generations glucose biosensors, procedure of making hydrogen peroxide based biosensor, synthesis of nanomaterials involved in hydrogen peroxide biosensor, and finally some examples of nanomaterials which intervene in hydrogen peroxide biosensor.

关键词： Biosensor Glucose Oxidase Hydrogen Peroxide Carbon Nanotubes Nanoparticles

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Effect of the seeds provenance and treatment on the germination rate and plants growth of four forest trees species of Cote d’Ivoire

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Journal of Forestry Research 2021年第1期32卷 161-169页

作者： Sélastique Doff ou Akaff ou AiméKouassi Kouame nestor Bi Boh Gore Georges Yao Abessika Henri Kouadio Kouassi Perla Hamon Sylvie Sabatier Jerome Duminil Department for Seeds and Seedlings Production Jean Lorougnon GuédéUniversityBP 150DaloaCote d’Ivoire IRD UMR DIADEB.P.6450134394 Montpellier Cedex 5France CIRAD UMR AMAP34398 MontpellierFrance

The rapid rate of deforestation in Cote d’Ivoire has led to loss of plant species diversity and also threatens some commercial tree species with *** reforestation and aff orestation has been ***,for some species,the numbers of surviving transplants has ***,it is necessary to develop properly adapted and resilient genotypes that can eff ectively support the programs of forest *** this context we evaluated the eff ects of the provenances of seeds and of various treatments on the germination rates and on plant growth of four commercial trees species(Pycnanthus angolensis,Terminalia superba,Mansonia altissima and Pterygota macrocarpa).We analyzed these parameters for seeds of three provenances(Daloa,Akoupéand Daoukro)of four species and for thirty plants aged 6 months per *** to begin germination and time to reach maximum germination were similar among species,and were not infl uenced by either treatment or *** seeds and those soaked for 24 and 48 h in water at room temperature yielded the highest germination rates,irrespective of species or *** one exception was ***,for which no germination was *** species,some provenances produced higher germination percentages than did *** clear relationship was computed between the germination rate and the morphometric characteristics of the seeds which varied signifi cantly between *** growth and morphological variability also depended greatly on *** factors might be implicated,therefore provenance trials should be undertaken and ***,molecular analysis should be undertaken to confi rm the implications of genetic factors and allow for genetic selection.

关键词： Forest trees Seed germination Plant growth Provenance Cote d’Ivoire

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Cardiac Surgery at Yaoundé General Hospital by a Local Team:Activity Report from September 2022 to January 2024

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World Journal of Cardiovascular Surgery（心血管外科国际期刊） 2024年第6期 87页

作者： Laurence Carole Ngo Yon Charles Mve Mvondo Hermann nestor Tsague Kengni Zephanie Kobe Fokalbo Sépolin Lowe Mireille Dakleu Alain Patrick Menanga William Ngatchou Djomo Vincent De Paul Djientcheu

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对马达加斯加大米市场分析中国和马达加斯加的关系的效用增加效率和价格的稳定

对马达加斯加大米市场分析中国和马达加斯加的关系的效用增加效率...

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作者： MENDRIKAHY JEAN nestor 南京农业大学

学位级别：硕士

2004年初,由于马达加斯加法郎贬值和国际大米价格飙升,马达加斯加面临生产短缺,进口大米的价格急剧上升,马达加斯加试图通过公开招标进口大米和补贴销售官方价格来稳定国内大米价格。本文讨论分析了自2004年大米危机以来的大米市场,记... 详细信息

2004年初,由于马达加斯加法郎贬值和国际大米价格飙升,马达加斯加面临生产短缺,进口大米的价格急剧上升,马达加斯加试图通过公开招标进口大米和补贴销售官方价格来稳定国内大米价格。本文讨论分析了自2004年大米危机以来的大米市场,记述了危机所引发的事件和随后的政府干预,并分析了政策实施后的影响,刺激国内大米市场的措施,以及中马合作对解决马达加斯加的混乱大米市场的作用。

关键词：中马合作杂交水稻大米经济大米危机效率提高大米相关外商直接投资

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Climate Projections and Uncertainties over South America from MRI/JMA Global Model Experiments

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Atmospheric and Climate Sciences 2012年第4期2卷 381-400页

作者： Josefina Blazquez Mario nestor Nunez Shoji Kusunoki Research Centre for Sea and Atmosphere(CIMA-CONICET/FCEN-UBA) Buenos AiresArgentina Department of Atmospheric and Oceanic Sciences(FCEN-UBA) Buenos AiresArgentina Franco-Argentine Institute for Climate Studies and Its Impacts(UMI IFAECI/CNRS) Buenos AiresArgentina Meteorological Research Institute TsukubaJapan

This paper analyses the climate change projected for the near and distant future in South America using MRI/JMA (Japanese Meteorological Agency) global model simulations with resolutions of 20 and 60 km. Changes in mean climate, as well as in the annual cycles and interannual variability of temperature and precipitation are discussed. An analysis is also made of the uncertainties of the 60 km resolution model experiments. For the near and distant future, both, the 20 km and 60 km resolution MRI/JMA models project that temperature changes will be positive in all seasons. The greatest values of change are over the Andes and over tropical and subtropical latitudes of the study region. In all the subregions analysed, the 20 km model projects greater changes in the annual cycle of mean temperature than the 60 km model. Changes in summer precipitation are positive over most of the continent, except for southern Chile. Autumn precipitation is projected to increase over northern Argentina and north-western South America and to decrease over central Chile in winter, which might be due to the southward shift of the Pacific storm-track. The most significant positive change in Southeastern South America (SESA) is projected to occur in spring precipitation. In general, projected changes in the annual cycle are greater in the rainy seasons of each subregion. No significant changes are expected in the interannual variability of temperature and precipitation. La Plata basin is projected to experience increased runoff, which would indicate that the projected rise in precipitation would have stronger effect than projected warming. The analysis of climate projection uncertainties revealed that temperature projections are more reliable than precipitation projections;and that uncertainty in near future simulations is greater than in simulations of the end of the century.

关键词： Climate Projections High Resolution Global Model South America Uncertainties

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Ecological Structure and Fruit Production of African Fan Palm (Borassus aethiopum) Populations

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American Journal of Plant Sciences 2011年第6期2卷 733-743页

作者： Christine Ouinsavi Charlemagne Gbémavo nestor Sokpon 不详

Ecological structure and fruit production of African fan palm stands in Benin were studied on the basis of surveys laid out in ten (10) populations located in three ecological zones. Dendrometric and fruit production parameters such as: diameter at breast height (dbh), total height (TH), number of fruit bunch per tree, number of fruits per tree, number of seeds per fruit, fruit length and width were measured on all African fan palm trees within thirteen (13) plots of 1,000 m2. Diameter and height classes distribution of the palms in each ecological zone adjusted to Weibull distribution showed a bell shaped curve with left dissymmetry, characteristic of young stands (form coefficient between 1 and 3.6). African fan palm stem number was 156 trees/ha. Variation of dbh, TH, number of fruit bunch per tree were highly significant between populations and ecological zones (P < 0.05%). Trees from Sudanian zone were highly grown (mean dbh = 52.2 cm) while those of Sudano - Guinean transition zone were less (mean dbh = 32.73 cm) and dominated by female trees. African fan palm stands of Pahou is suitable for seed collection for in situ conservation of the species while those of Ouorghi and Akomiah could provide fruits for edible hypocotyls production.

关键词： Ecological Structure African Fan Palm Fruit Production Population

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Distinction of an Assortment of Deep Brain Stimulation Parameter Configurations for Treating Parkinson’s Disease Using Machine Learning with Quantification of Tremor Response through a Conformal Wearable and Wireless Inertial Sensor

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Advances in Parkinson's Disease 2020年第3期9卷 21-39页

作者： Robert LeMoyne Timothy Mastroianni Donald Whiting nestor Tomycz Department of Biological Sciences Northern Arizona University Flagstaff AZ USA Cognition Engineering Pittsburgh PA USA Department of Neurosurgery AHN Neuroscience Institute Pittsburgh PA USA AHN Department of Neurosurgery Pittsburgh PA USA

Deep brain stimulation offers an advanced means of treating Parkinson’s disease in a patient specific context. However, a considerable challenge is the process of ascertaining an optimal parameter configuration. Imperative for the deep brain stimulation parameter optimization process is the quantification of response feedback. As a significant improvement to traditional ordinal scale techniques is the advent of wearable and wireless systems. Recently conformal wearable and wireless systems with a profile on the order of a bandage have been developed. Previous research endeavors have successfully differentiated between deep brain stimulation “On” and “Off” status through quantification using wearable and wireless inertial sensor systems. However, the opportunity exists to further evolve to an objectively quantified response to an assortment of parameter configurations, such as the variation of amplitude, for the deep brain stimulation system. Multiple deep brain stimulation amplitude settings are considered inclusive of “Off” status as a baseline, 1.0 mA, 2.5 mA, and 4.0 mA. The quantified response of this assortment of amplitude settings is acquired through a conformal wearable and wireless inertial sensor system and consolidated using Python software automation to a feature set amenable for machine learning. Five machine learning algorithms are evaluated: J48 decision tree, K-nearest neighbors, support vector machine, logistic regression, and random forest. The performance of these machine learning algorithms is established based on the classification accuracy to distinguish between the deep brain stimulation amplitude settings and the time to develop the machine learning model. The support vector machine achieves the greatest classification accuracy, which is the primary performance parameter, and K-nearest neighbors achieves considerable classification accuracy with minimal time to develop the machine learning model.

关键词： Parkinson’s Disease Deep Brain Stimulation Wearable and Wireless Systems Conformal Wearable Machine Learning Inertial Sensor Accelerometer Wireless Accelerometer Hand Tremor Cloud Computing Network Centric Therapy Python

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横风大雨对高速列车绕流的影响

横风大雨对高速列车绕流的影响

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作者： nestor DAVID MEJIA 北京交通大学

学位级别：硕士

随着社会的发展,对交通运输工具的安全、高速、及运载力的要求日益增加。高速铁路是供乘客使用的轨道交通,其运行速度比普通速度的铁路交通有着显著的提高。在安全运行的条件下,其速度可达400-450km/h。然而,横风、大雨等自然现象会对... 详细信息

随着社会的发展,对交通运输工具的安全、高速、及运载力的要求日益增加。高速铁路是供乘客使用的轨道交通,其运行速度比普通速度的铁路交通有着显著的提高。在安全运行的条件下,其速度可达400-450km/h。然而,横风、大雨等自然现象会对高速列车的安全行驶起到负面影响。本文旨在通过研究现代化高速运载工具,从而对经济、环境及技术的可行性的研究提供依据。高速列车的空气动力学特性不仅与其运行效益紧密相关,还与安全性,以及在极端天气条件和其他外部因素下的运行性能密切相关。一些学者研究了横风和大雨对高速列车气动力的影响,但仍然需要进一步的深入研究。本研究的目的在于：1)分析安全行驶的速度范围及其特性;2)研究大雨对高速列车的影响,加深对这项对安全至关重要的因素的认识;3)分析表面压强分布及其对几何设计和运行性能的影响;4)对数值模拟结果进行分析,并与其他研究者在相关研究中提及的概念与理论框架进行验证。在此背景下,现有的知识与研究为进一步的研究提供了基础与依据。本文涉及空气动力学、流体力学、流体动力学、数值分析、计算流体动力学和多相流分析的理论与计算,列车车身绕流考虑了横向风的作用和雨的作用。采用多相流混合模型理论、realizable k-∈湍流模型、多面体网格和标准壁面函数对各项参数进行分析。使用高端台式电脑客户端,数值模拟计算软件使用ANSYS WORKBENCH-FLUENT,结构设计使用整合了Autodesk Inventor与Nx7.5的标准CAD平台。本研究使用了三组不同大小的网格,其单元数量分别为：1824488;2285764;和3555243。这三个有限元组的选择是根据计算和时间的限制确定的。列车的性能一部分是由它的结构决定的,还有很重要的一部分是由外部条件决定的,例如横风和雨。在研究横风影响时,选取以下速度：24m/s,20m/s,16m/s,10m/s,4m/s。参照邵雪明等人的相关研究,降雨量取60mm/h,每滴雨速度5m/s。考虑到网格设计理论与模型,使用y+壁面函数,在列车模型的重要部分,如车头和车尾,y+取30-60;考虑到计算能力的限制,列车其他部分y+选取120-200。通过研究,本文得到以下结论： ●由于数值模拟的计算时间与计算条件有限,圆柱形计算域与多面体网格对本文的数值模拟最为合适。 ·最大压强和最小压强分别分布在车头和车尾。 ·阻力、升力、侧向力、滚动力矩和偏航力矩在横风和大雨的环境下显著增大。 ·高速列车系统在大雨条件下运行是不安全的,其出轨和倾覆的可能性很高。 ●在使用CFD进行数值模拟计算时,为避免结果失真,例如出现回流和残差过大,计算区域的大小、松弛因子、以及离散方法的选择至关重要。

关键词：计算流体动力学空气动力学高速列车横风雨多相流

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Preliminary Network Centric Therapy for Machine Learning Classification of Deep Brain Stimulation Status for the Treatment of Parkinson’s Disease with a Conformal Wearable and Wireless Inertial Sensor

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Advances in Parkinson's Disease 2019年第4期8卷 75-91页

The concept of Network Centric Therapy represents an amalgamation of wearable and wireless inertial sensor systems and machine learning with access to a Cloud computing environment. The advent of Network Centric Therapy is highly relevant to the treatment of Parkinson’s disease through deep brain stimulation. Originally wearable and wireless systems for quantifying Parkinson’s disease involved the use a smartphone to quantify hand tremor. Although originally novel, the smartphone has notable issues as a wearable application for quantifying movement disorder tremor. The smartphone has evolved in a pathway that has made the smartphone progressively more cumbersome to mount about the dorsum of the hand. Furthermore, the smartphone utilizes an inertial sensor package that is not certified for medical analysis, and the trial data access a provisional Cloud computing environment through an email account. These concerns are resolved with the recent development of a conformal wearable and wireless inertial sensor system. This conformal wearable and wireless system mounts to the hand with the profile of a bandage by adhesive and accesses a secure Cloud computing environment through a segmented wireless connectivity strategy involving a smartphone and tablet. Additionally, the conformal wearable and wireless system is certified by the FDA of the United States of America for ascertaining medical grade inertial sensor data. These characteristics make the conformal wearable and wireless system uniquely suited for the quantification of Parkinson’s disease treatment through deep brain stimulation. Preliminary evaluation of the conformal wearable and wireless system is demonstrated through the differentiation of deep brain stimulation set to “On” and “Off” status. Based on the robustness of the acceleration signal, this signal was selected to quantify hand tremor for the prescribed deep brain stimulation settings. Machine learning classification using the Waikato Environment for Kn

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Foraging and Pollination Behaviour of Apis mellifera adansonii Latreille （Hymenoptera, Apidae） on Gossypium hirsutum （Malvaceae） Flowers at Dang （Ngaoundere, Cameroon）

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Journal of Agricultural Science and Technology(A) 2013年第4期3卷 267-280页

作者： Mazi Sanda Tchuenguem Fohouo Femand-nestor Briackner Dorothea Department of Biological Sciences University of Ngaounddrd P.O. Box 454 Ngaounddrd Cameroon Forschungsstelle ffir Bienenkunde Universitdt Bremen FB2 Postfach 330440 28334 Bremen Germany

To evaluate Apis mellifera adansonii Latreille impact on fruit and seed yields of Gossypium hirsutum L., its foraging and pollinating activities were studied in Ngaoundere for two seasons. Observations were made on 340 flowers each year and divided in three treatments. The treatments included unlimited flowers access by all visitors; bagged flowers to deny all visits and limited visits by Apis mellifera adansonii only. The worker bees seasonal rhythm of activity, its foraging behaviour, its pollination efficiency, the fruiting rate, the number of seeds per fruit and the percentage of normal seeds were evaluated. Results show that this bee foraged G. hirsutum flowers throughout the whole blooming period. This bee species intensely harvested pollen and nectar. The mean foraging speed was 9.41 flowers per rain in 2009 and 8.41 flowers per min in 2010. The fruiting rate, the number of seeds per fruit and the percentage of normal seeds of unprotected flowers were significantly higher than those of flowers protected from insects. Through its pollination efficiency, Apis mellifera adansonii provoked a significant increment of the fruiting rate by 60.84% in 2009 and 36.48% in 2010, as well as the number of seeds per fruit by 94.16% in 2009 and 31.41% in 2010, and the percentage of normal seeds by 94.23% in 2009 and 33.49% in 2010. The installation ofA. m. adansonii colonies close to G. hirsutum fields could be recommended to increase fruit, seed and honey yields, and pollen production as a hive product in the region.

关键词： Gossypium hirsutum Apis mellifera adansonii foraging pollination

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