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Phytochemical Tests, Assessment of Antioxidant Properties and Isolation of Two compounds of Ethyl Acetate Extract of chadian Propolis: case of Bebotho (Southern chad)

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American Journal of Analytical chemistry 2022年第7期13卷 241-254页

作者： Salomon Madjitoloum Betoloum Abel Mbaiogaoun severin Mbaihougadobe Emmanuel Talla Department of chemistry Faculty of Exact and Applied Sciences (FSEA) University of N’Djamena N’Djamena The Republic of Chad Department of chemistry Faculty of Science University of Ngaoundéré (UN) Ngaoundéré The Republic of Cameroon

The present work deals with the research of chemical constituents and evaluation of antioxidant properties of Bebotho propolis. From the ethyl acetate extract, we isolated, using various chromatographic techniques, a mixture of two identical compounds (isomers) indexed PBy4a and PByb. The structures of these compounds were elucidated by means of spectroscopic analysis techniques (MS, IR, 1H-NMR, 13c-NMR, HMBc and HSQc) and by comparison of the spectral data with those described in the literature. Thus, these compounds were identified to a mixture of two chromones namely 5,7-dihydroxy-2-methylchromone-6-c-α-D-glucopyranoside and 5,7-dihydroxy-2-methylchromone-8-c-β-D-glucopyranoside, first reported in propolis. The study of the antiradical power, chelating power and the quantification of phenolic compound of these same extracts, showed interesting properties that propolis extracts have to scavenge free radicals.

关键词： Isolation Propolis chelating Power 5 7-Dihydroxy-2-Methylchromone-6-c-α-D-Glucopyranoside and 5 7-Dihydroxy-2-Methylchromone-8-c-β-D-Glucopyranoside

Management of acute heart failure-Is there a paradigm shift around the corner?

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World Journal of cardiovascular Diseases 2013年第2期3卷 1-7页

作者： c. Pater, T. severin Novartis Pharma AG Basel Switzerland

It has become increasingly apparent that the looming epidemic of heart failure calls for systematic treatment approaches tailored to the needs of individual patient phenotypes. Although chronic heart failure (cHF) therapies are continuously evolving based on the increasing understanding of the involved etiology, acute heart failure (AHF) therapies are still based on hemodynamic improvements and symptom alleviation. Guidelines on AHF management have highlighted that the currently administered AHF therapies lack evidence and have raised concerns on the safety and efficacy of some of the hitherto accepted treatment modalities. Additionally, the high mortality and morbidity rates associated with the current AHF therapies also add to the imperative need to revisit AHF management. The last decade has witnessed a paradigm shift in the way we define and diagnose AHF. Apart from it being recognized as a distinct clinical entity, research has also led to new data on the pathophysiological changes associated with AHF. These developments along with the limited short- and long-term effects of currently used therapies may herald a paradigm shift in the way we plan and deliver management strategies to treat the pathological progression of heart failure.

关键词： Acute Heart Failure Hemodynamic clinical and Residual congestion Vasodilators Diuretics Management Strategies

脉冲Nd∶YAG激光联合羟基磷灰石对根尖切除的作用(英文)

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中国激光医学杂志 1999年第3期8卷 172-174页

作者： Y.BENHATIT P.GOUDOT O.DILANcHIAN c.severin K.SOHRABI European Laser Academy Prof.Dr.Y.BENHATITBd.L.METTEWIE471080 BrusselsBelgiumEuropean Laser AcademyProf.D

目的　评价脉冲Nd∶YAG 激光对应用羟基磷灰石的根尖切除术后的牙齿根部的作用。方法　70 颗拔出的上颌中切齿,牙髓腔扩张后用马来乳胶封闭并覆以氧化锌。随机分为7 组,每组10 颗,第1 组为对照组;第2 、3 、4 组为单纯激光照射组,以脉... 详细信息

目的　评价脉冲Nd∶YAG 激光对应用羟基磷灰石的根尖切除术后的牙齿根部的作用。方法　70 颗拔出的上颌中切齿,牙髓腔扩张后用马来乳胶封闭并覆以氧化锌。随机分为7 组,每组10 颗,第1 组为对照组;第2 、3 、4 组为单纯激光照射组,以脉冲Nd∶YAG 激光照射,脉宽150 μs,最高频率30 Hz,波长1064 nm ,照射时间20 s,功率分别为0-5 、1-0 、1-5 W;第5 、6 、7 组为羟基磷灰石加激光照射组,去除马来乳胶0-5 mm ,换以羟基磷灰石,激光照射方法同2 、3 、4 组。7组牙齿标本均进行扫描电镜下观察。结果　电镜观察可见单纯激光照射组牙本质表面出现很多孔状熔化及结晶;羟基磷灰石处理组,激光照射后羟基磷灰石未见明显改变,而在其周围的牙本质表面出现熔化及结晶,在二者之间有明显界限,说明二者没有相互融合。结论　脉冲Nd∶YAG 激光对羟基磷灰石物质无明显作用,牙本质与羟基磷灰石之间也没有反应;在实验所用激光剂量范围内,激光照射可造成牙本质熔化及结晶。

关键词：激光根尖切除术羟基磷灰石

前房水流量的测量——扫描荧光光度计与裂隙灯荧光光度计的比较

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中华眼科杂志 1987年第1期23卷 30-33页

作者：李平余 JH Williams SM Podos c.severin 美国纽约市大学Mount Sinai医学院眼科

对于人和实验动物反复地无损伤地测量前房水流量,荧光光度测量是一种有用的方法.在本实验中,我们对比了扫描荧光光度计和裂隙灯荧光光度计对 cynomolgus 猴眼前房水流量的测量结果。两种仪器测量的结果类似。对20只猴眼的测量结果如下:...

对于人和实验动物反复地无损伤地测量前房水流量,荧光光度测量是一种有用的方法.在本实验中,我们对比了扫描荧光光度计和裂隙灯荧光光度计对 cynomolgus 猴眼前房水流量的测量结果。两种仪器测量的结果类似。对20只猴眼的测量结果如下:扫描荧光光度计测得的前房水流量为1.61±0.05 μL/min;裂隙灯荧光光度计测得的前房水流量为1.59±0.05 μL/min(平均值±标准误)。

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Sero-Prevalence and Risk Factors of Diffusion of Peste des Petits Ruminants in cameroon

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Open Journal of Veterinary Medicine 2020年第7期10卷 103-115页

作者： severin Loul Abel Wade Alexandre Michel Njan Nlôga Ministry of Livestock Fisheries and Animals Industries Yaounde Cameroon center of Research on Emerging and Reemerging Diseases Yaounde Cameroon National Veterinary Laboratory Garoua Cameroon Faculty of Science University of Ngaoundere Ngaoundere Cameroon

The present study was carried out between April 2015 and January 2016 to estimate the sero-prevalence and identify the risk factors of the peste des petits ruminants (PPR) in cameroon. A total of 269 herds randomly sampled across the country have been studied and 1622 samples of serum have been levied on the sheep and goat. The c-ELISA has been studied in order to detect the presence of antibodies in small ruminants like an indicator of exposition to PPRV. The results revealed the circulation of PPRV in the country with a total sero-prevalence of 39% [95%cI;37 - 41] and a sero-prevalence of 63.2% [95%cI;57.2 - 69.2] at the herd level. Sero-prevalence was variable in the ten regions ranging from 7% [95% cI;6.2 - 8.4] to 73% [95% cI;62 - 84] with the northern zone (Adamawa, North and Far-North) having 52.3% [95% cI;37 - 60] and southern zone (including the remaining seven regions) recording 29% [95% cI;11 - 57]. Similarly, it was higher in animals found in urban/peri-urban areas than in rural areas with prevalence ratio of 2.9 [95% cI 2.54 - 3.4;p i.e. 3 times more, 1.6 [95% cI 1.36 - 1.90;p i.e. 1.6 times more, and 5.02 [95% cI 3.91 - 6.85;p i.e. 5 times more at national level, in the northern zone and in the southern area, respectively. Five risk factors have been identified: the breeding environment, introduction of new animals into the herds, gathering of animals for pasture and watering, wandering and transhumance. The breeding area appeared to be the most important risk factor associated with disease exposure. The control measures for the eradication of this disease must take into account the epidemiological situation, the breeding environment, animal transhumance and breeding system.

关键词： Small Ruminants Sero-Prevalence Risk Factors Peste des Petits Ruminants cameroon

Genetic Diversity of Taro Landraces from côte d’Ivoire Based on Qualitative Traits of Leaves

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Agricultural Sciences 2021年第12期12卷 1433-1446页

作者： Jean-Michel Niambet Koffi Kevin Kouamé Koffi severin Beket Bonny Arsène Irié Zoro Bi Unité de Phytotecthnie et Amélioration Génétique UFR des Sciences de la Nature Université Nangui Abrogoua Abidjan C&#244 te d’Ivoire

Taro is an important crop species in côte d’Ivoire. It is cultivated for its tubers and leaves. But its knowledge and genetic diversity and differentiation are very weakly documented. Several morphological types are found in rural area, but their identification is not very clear, and their agronomic potentiality is underexploited. In this context we initiated a survey and collected 213 accessions from 14 growing regions of côte d’Ivoire. The diversity was evaluated based on seven qualitative traits of leaves (Shape of the base of the leaf, Predominant position (shape) of the leaf blade surface, Margin of the leaf blade, Leaf blade variegation, Profile of the petiolar junction, Shape of the leaf sheath, Shape of the appendix) during an experimentation conducted in rural area. The objective of this study was to characterize the collection of taros collected in different geographical zones of côte d’Ivoire and identify the genera cultivated. Results of our study indicated that excepted margin of the leaf blade all traits are very discriminant. Several variants were observed for each of traits. According to observations and statistics analysis accessions were separated into two main groups. The characteristics of these groups indicate that taro cultivated in côte d’Ivoire could belong to two genera: Xanthosoma and colocasia.

关键词： côte d’Ivoire colocasia Diversity Taro Xanthosoma

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符合新兴市场废气排放法规要求的柴油机开发

汽车与新动力 2013年第2期45卷 30-33页

作者： Busch H Henning L Krfer T severin c 张慰

为了降低因交通工具引发的二氧化碳排放,进行了广泛的研究,为此,全球柴油车的销量得到大幅提高。同时,由于日益严格的排放限值要求,在新兴市场中也开始采用排气后处理系统,诸如开放式或封闭式柴油颗粒捕集器。介绍了FEV公司根据这些国... 详细信息

为了降低因交通工具引发的二氧化碳排放,进行了广泛的研究,为此,全球柴油车的销量得到大幅提高。同时,由于日益严格的排放限值要求,在新兴市场中也开始采用排气后处理系统,诸如开放式或封闭式柴油颗粒捕集器。介绍了FEV公司根据这些国家的边界条件提出的排放控制理念和排气后处理技术及其面临的挑战,以及对此所采取的一些合适的解决方案。

关键词：柴油颗粒捕集器排气后处理燃油品质新兴市场降低排放

Qualitative Assessment and Typology of the Water Resource Used for the Production of Drinking Water in Duékoué, Western côte d’Ivoire

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Journal of Geoscience and Environment Protection 2019年第5期7卷 212-231页

作者： Kouamé Kouakou Benoit Konan Kouakou Séraphin Attoungbre Kouakou severin Konan Koffi Félix Boussou Koffi charles Kouamé Kouamé Martin Laboratory of Geosciences and Environment University Jean Lorougnon Guédé Daloa C&#244 te d’Ivoire Laboratory of Ecology Biodiversity and Evolution University Jean Lorougnon Guédé Daloa C&#244 te d’Ivoire

The objective of this study was to evaluate the typology of water through physicochemical and bacteriological characterization with the aim of highlighting its vulnerability as a drinking water resource. The methodology adopted was to evaluate the level of pollution by monitoring the spatiotemporal variation of the water pollution indicator levels of Lake Dohou. The sampling frequency is monthly for one year, from November 2017 to October 2018, in order to obtain a fairly representative image of water quality and its seasonal evolution in eight (8) well-defined stations. The parameters were determined using the standard methods defined by the French Association for Standardization (AFNOR). This study shows that the waters are acidic, with an average pH of 5.81 and a low electrical conductivity of between 42.67 ± 4.30 and 59.62 ± 21.84 μ***-1. At all stations, seasonal mean water transparencies are low (collected had total nitrogen (TN) levels above the limit of 4 mg.L-1. All of the lake’s waters have non-compliant BOD5 (2.L-1) for raw water intended for the production of drinking water. Sites D6 and D7 have cOD/BOD5 ratio greater than 3, which indicates the presence of non-biodegradable organic matter in these areas. Total coliforms, Escherichia coli and Enterococci were present in 100% (28/28) water samples at concentrations ranging from 2300 to 173,000 cFU/100 mL, from 100 to 1650 cFU/100 mL and from 20 to 1140 cFU 1/100 mL respectively. For Salmonella pathogens, they were detected in 50% of the dry season samples and in 100% of the rainy season samples. This almost permanent presence of this pathogenic germ denotes a poor quality of water with reference to this parameter. The presence of total coliform and other microbial contaminants suggests that supplied water is highly contaminated with pathogens and great reservoirs for them. Principal component analysis (PcA) of the physicochemical data set allowed de

关键词： Dohou Lake Water Quality coliform Fecal coliform Physico-chemical Parameters Typology and Variation

Multimodal nonlinear endomicroscopic imaging probe using a double-core double-clad fiber and focus-combining micro-optical concept

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Light(Science & Applications) 2021年第11期10卷 2173-2183页

作者： Ekaterina Pshenay-severin Hyeonsoo Bae Karl Reichwald Gregor Matz Jörg Bierlich Jens Kobelke Adrian Lorenz Anka Schwuchow Tobias Meyer-Zedler Michael Schmitt Bernhard Messerschmidt Juergen Popp GRINTEcH GmbH Schillerstr.107745JenaGermany Leibniz Institute of Photonic Technology Member of Leibniz Health TechnologiesAlbert-Einstein-Str.907745JenaGermany Institute of Physical chemistry and Abbe center of Photonics Friedrich Schiller University JenaHelmholtzweg 407743JenaGermany

Multimodal non-linear microscopy combining coherent anti-Stokes Raman scattering,second harmonic generation,and two-photon excited fluorescence has proved to be a versatile and powerful tool enabling the label-free investigation of tissue structure,molecular composition,and correlation with function and disease *** a routine medical application,the implementation of this approach into an in vivo imaging endoscope is ***,this is a difficult task due to the requirements of a multicolour ultrashort laser delivery from a compact and robust laser source through a fiber with low losses and temporal synchronization,the efficient signal collection in epi-direction,the need for small-diameter but highly corrected endomicroobjectives of high numerical aperture and compact ***,we introduce an ultra-compact fiber-scanning endoscope platform for multimodal non-linear endomicroscopy in combination with a compact four-wave mixing based fiber *** heart of this fiber-scanning endoscope is an in-house custom-designed,single mode,double clad,double core pure silica fiber in combination with a 2.4 mm diameter NIR-dual-waveband corrected endomicroscopic objective of 0.55 numerical aperture and 180µm field of view for non-linear imaging,allowing a background free,low-loss,high peak power laser delivery,and an efficient signal collection in backward direction.A linear diffractive optical grating overlays pump and Stokes laser foci across the full field of view,such that diffraction-limited performance is demonstrated for tissue imaging at one frame per second with sub-micron spatial resolution and at a high transmission of 65%from the laser to the specimen using a distal resonant fiber scanner.

关键词： fiber double scanner