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Efficiency and productivity analysis of vegetable farming within root and tuber-based systems in the humid tropics of Cameroon

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journal of Integrative Agriculture 2017年第8期16卷 1865-1873页

作者： Ajapnwa Akamin jean-claude Bidogeza jules Rene Minkoua N Victor Afari-Sefa Faculty of Economics and Management University of Yaounde IIP.O.Box 18 Soa YaoundeCameroon Liaison Office Cameroon West and Central AfricaWorld Vegetable CenterP.O.Box 2008 Messa YaoundeCameroon Samanko Research Station West and Central AfricaWorld Vegetable CenterP.O.Box 320 BemakoMali

The study analyzes the technical efficiency of vegetable farmers in root and tuber-based farming systems within selected sites of the humid tropics of Cameroon. Multistage sampling was used to collect primary data from a cross-section of vegetable farmers drawn from eight selected sites in Santa sub division, Northwest region of Cameroon. Stochastic frontier analysis was used to estimate the technical efficiency of vegetable farmer and to examine its determinants. The results showed that farmyard manure was the most productive factor input, followed by farm equipment and labor. The mean technical efficiency level was 67%, revealing production shortfalls and indicating possibilities of significantly increasing production with the current input jevels. Female, as well as more educated farmers were found to be significantly more efficient than their counterparts. The results also showed that farmers become less technical efficient as farm sizes become larger. Our study findings suggest that smallholder farmers＇ access to manure, farm implements, and increased women participation in vegetable farming, will produce huge payoffs in vegetable production efficiency in Cameroon.

关键词： technical efficiency vegetable productivity farming systems intensification crop diversification stochasticfrontier analysis

Results of the First 10 Cases of Coronary Bypass Surgery in Senegal

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World journal of Cardiovascular Surgery 2024年第4期14卷 45-60页

作者： Papa Amath Diagne jean claude Ndiogou Dione Papa Ousmane Ba Momar Sokhna Diop El Hadji Boubacar Ba Momar Dioum Marième Soda Mbaye Moussa Seck Diop Mory Camara Abdou Lahad Mbengue Abdou Aziz Thiaw Abdoul Khoudoss Diallo Moussa Mareme Samba Dialtabé Ibrahima Guéssé Ba Anta Mbaye Sall Papa Salmaneba Amadou Gabriel Ciss Department of Cardiovascular and Thoracic Surgery FANN National University Hospital Dakar Senegal

This is a review of the first 10 coronary artery bypass surgeries performed by the local team. The mean age was 62 years old [45 - 74]. The patients were predominantly male, with a M/F ratio of 4:1. Cardiovascular risk factors were mainly myocardial infarction (MI) (60%), hypertension (50%), obesity (40%) and diabetes (30%), with at least two risk factors per patient. Angina was the main symptom (80%). The average time from presentation to surgery was 8 months. The mean Euroscore 2 was 2.92 ± 1.65 [1.33 - 6.60]. Coronary angiography revealed an average of 2 lesions per patient, with 3-vessel involvement in 70% of cases: the Interventricular artery (IVA) (100%), the right coronary artery (90%) and the circumflex artery (70%). On echocardiography, the mean Left ventricular ejection fraction (LVEF) was 59% [33% - 76%]. All patients underwent median sternotomy with bypass grafting. The average duration of the cardiopulmonary bypass was 150 min [46 - 275 min];that of aortic clamping, 120 min [43 - 232 min]. The grafts used were internal thoracic artery (ITA) in 100% of cases (80% on the left and 20% on the right), and the great saphenous vein (GSV) in 60% of cases (50% on the left and 10 on the right). Double bypass was performed in 60% of cases, single bypass in 30% and triple bypass in 10%. The bypasses were performed on the IVA (100%), the middle lateral of the circumflex (30%) and the bisector (20%). The average time to extubation was 11 hours and the length of stay in the intensive care unit was 7 days [03 - 17 days]. One patient had a reoperation on Day 0 post-op. The average hospital stay was 13 days [06 - 27 days]. Complications occurred in nine of the patients (90%), with a predominance of infectious and neurological complications. Overall operative mortality was 3%, all in intensive care.

关键词： Coronary Bypass Surgery Coronary Lesions Cardiac Surgery Senegal

Efficient unidirectional polarization-controlled excitation of surface plasmon polaritons

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Light(Science & Applications) 2014年第1期3卷 100-105页

作者： Anders Pors Michael G Nielsen Thomas Bernardin jean-claude Weeber Sergey I Bozhevolnyi Department of Technology and Innovation University of Southern DenmarkOdenseDenmark LICB UMR 6303 CNRS–University of BurgundyF-21078 DijonFrance

Efficient excitation of surface plasmon polaritons(SPPs)remains one of the most challenging issues in areas of plasmonics related to information communication *** particular,combining high SPP excitation efficiency and acceptance of any polarization of incident light appeared to be impossible to attain due to the polarized nature of *** we demonstrate plasmonic couplers that represent arrays of gap SPP resonators producing upon reflection two orthogonal phase gradients in respective linear polarizations of incident *** couplers are thereby capable of efficiently converting incident radiation with arbitrary polarization into SPPs that propagate in orthogonal directions dictated by the phase *** couplers operate at telecom wavelengths and feature the coupling efficiency of,25%for either of two linear polarizations of incident radiation and directivity of SPP excitation exceeding *** further demonstrate that an individual wavelength-sized unit cell,representing a meta-scatterer,can also be used for efficient and polarization sensitive SPP excitation in compact plasmonics circuits.

关键词： gap surface plasmons metamaterials metasurfaces surface plasmon polaritonsgap surface plasmons metamaterials metasurfaces surface plasmon polaritons

Utility of combining spectral domain optical coherence tomography structural parameters for the diagnosis of early Glaucoma: a mini-review

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Eye and Vision 2018年第1期5卷 91-101页

作者： jean-claude Mwanza joshua L.Warren Donald L.Budenz Department of Ophthalmology School of MedicineUniversity of North Carolina at Chapel HillChapel HillNCUSA Department of Biostatistics Yale UniversityNew HavenCTUSA

Optical coherence tomography(OCT)has moved to the forefront of imaging modalities in the management of glaucoma and retinal *** is modifying how glaucoma and glaucoma progression are diagnosed clinically and augmenting our understanding of the *** provides multiple parameters from various anatomic areas for glaucoma diagnosis,evaluation of treatment efficacy,and progression *** the use of multiple parameters has increased the likelihood of detecting early structural changes,diagnosing glaucoma in early stages is often challenging when the damages are subtle and not apparent on OCT scans,in addition to the fact that assessment of OCT parameters often yields conflicting *** promising approach is to combine multiple individual parameters into a composite parameter from the same test to improve diagnostic accuracy,sensitivity,and *** review presents current evidence regarding the value of spectral domain OCT composite parameters in diagnosing early glaucoma.

关键词： Optical coherence tomography Combination of parameters Early glaucoma

Profile of retinal diseases in adult patients attending two major eye clinics in Kinshasa,the Democratic Republic of Congo

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International journal of Ophthalmology(English edition) 2020年第10期13卷 1652-1659页

作者： Nelly N.Kabedi David L.Kayembe jean-claude Mwanza Departmemt of Ophthalmology School of MedicineUniversity of KinshasaKinshasa XIDemocratic Republic of Congo Department of Ophthalmology School of MedicineUniversity of North Carolina at Chapel HillNC 27599USA

AIM:To determine the frequency and types of retinal diseases and the extend of the related visual loss in adult patients attending two public eye clinics of Kinshasa,Democratic Republic of ***:Review of medical records of patients with retinal diseases seen in the major eye clinics in Kinshasa,the University Hospital of Kinshasa(UHK)and Saint joseph Hospital(SjH),from january 2012 to December *** and diagnoses were retrieved and *** measures were frequency and prevalence of retinal diseases,blindness and low ***:A total of 40965 patients aged 40 y or older were examined during this period in both *** these,1208 had retinal disease,giving a 3-year and an annual prevalence of 3%and 1%,*** age was 61.7±10.7 y,and 55.8%of the patients were *** hypertension(68.1%)and diabetes(43.3%)were the most common systemic *** retinopathy(41.8%),diabetic retinopathy(37.9%),age-related macular degeneration(AMD;14.6%),and chorioretinitis and retinal vein occlusion(7.3%each)were the most common retinal diseases,with 3-year prevalence rates of 1.3%,1.0%,0.43%,and 0.21%*** low vision and blindness were present in 26.8%and 8.4%of the patients at *** causes of low vision and blindness were diabetic retinopathy(14.8%),AMD(4.9%),retinal detachment(2.8%),and retinal vein occlusion(2.5%).The prevalence was significantly higher among males than females,and at the UHK than ***:Retinal diseases are common among Congolese adult patients attending eye clinics in *** cause a significant proportion of low vision and blindness.

关键词： retinal disorders Kinshasa,Democratic Republic of Congo sub-Saharan Africa pattern

Integrating Functional Status Information into Knowledge Graphs to Support Self-Health Management

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Data Intelligence 2023年第3期5卷 636-662页

作者： Mauro Dragoni Tania Bailoni Ivan Donadello jean-claude Martin Helena Lindgren Fondazione Bruno Kessler TrentoItaly Free University of Bolzano BolzanoItaly LISN-CNRS Universite Paris SaclayParisFrance Umea University UmeaSweden

Functional Status Information(FSI)describes physical and mental wellness at the whole-person *** includes information on activity performance,social role participation,and environmental and personal factors that affect the well-being and quality of *** and analyzing this information is critical to address the needs for caring for an aging global population,and to provide effective care for individuals with chronic conditions,multi-morbidity,and *** knowledge graphs(PKGs)represent a suitable way for meaning in a complete and structured way all information related to people's FSI and reasoning over them to build tailored coaching solutions supporting them in daily life for conducting a healthy *** this paper,we present the development process related to the creation of a PKG by starting from the HeLis ontology in order to enable the design of an Al-enabled system with the aim of increasing,within people,the self-awareness of their own functional *** particular,we focus on the three modules extending the HeLis ontology aiming to represent(i)enablers and(ii)barriers playing potential roles in improving(or deteriorating)own functional status and(iii)arguments driving the FSI collection ***,we show how these modules have been instantiated into real-world scenarios.

关键词： Knowledge Graph Personal Healthcare Functional Status Enablers Barriers Arguments

Effects of water-borne copper on the gills and hepatopancreas of Macrobrachium rosenbergii

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Integrative Zoology 2008年第4期3卷 299-310页

作者： Na LI Qiang MA jian YANG Yunlong ZHAO jean-claude BROCHON School of Life Science East China Normal UniversityShanghaiChina Key Laboratory of Ecological Environment and Resources of Inland Fisheries Freshwater Fisheries Research CenterChinese Academy of Fishery SciencesWuxiChina National Research Center Laboratory of Biotechnology and Application Genetic PharmacologyEcole Normale Supérieure CachanCachan cedexFrance

We focused on elucidating the toxic effects of water-borne copper on the giant freshwater prawn Macrobrachium *** seven days of exposure to copper(Cu2+)at concentrations ranging from 0.01 mg L–1 to 0.5 mg L–1,three isozymes,malate dehydrogenase,alkaline phosphatase and esterase,were analyzed and compared using polyacrylamide electrophoresis(PAGE)and biochemical *** results indicated that the electrophoretic patterns of the isozymes showed a copper-concentration-related *** doses of copper stimulated strong expression of the three *** patterns of malate dehydrogenase and alkaline phosphatase gradually became weaker or even lost as the level of copper *** contrast,esterase patterns exhibited an increased molecular heterogeneity at higher copper concentrations.A transmission electron microscope was used to study ultrastructure differences in the gills and hepatopancreas of ***,and the results showed significant structural damage at increased levels of copper compared with the control *** basement mem-branes and mitochondira in the gills were seriously damaged,the cuticle electron density distribution was not homogeneous,and an infolded basement membrane,circularized nucleus,disintegrated nuclear membrane,and decreased mitochondria number and size were observed in the ***,flowing out of karyoplasms,partly falling microvilli,decreased mitochondrion,partly disappeared mitochondrial cristae,and a thinned matrix were observed in the *** findings indicate that exposure to elevated copper levels might damage the ultrastructure of the gills and hepatopancreas of *** and might further weaken their normal physical *** were quite sensitive to environmental stress and changes in isozyme elctrophoretic patterns might be effective biomarkers of environmental contamination.

关键词： copper gills hepatopancreas isozymes Macrobrachium rosenbergii polyacrylamide electrophoresis.

Analysis of the Progressive Collapse Behavior of the RC Frame Structures Reinforced by High-Performance Composite Material

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Analysis of the Progressive Collapse Behavior of the RC Fram...

作者： Evina Mvondo jean claude（艾维）东南大学

学位级别：硕士

本文旨在对钢-连续纤维复合筋(Steel Fiber Composite Bar,简称SFCB)加固钢筋混凝土框架抗连续倒塌性能进行分析研究,利用软件SAP2000.V15.0.1,建立了 22mx18m,层高16m的典型钢筋混凝土框架结构模型,进行传统钢筋加固和SFCB筋加固下结... 详细信息

本文旨在对钢-连续纤维复合筋(Steel Fiber Composite Bar,简称SFCB)加固钢筋混凝土框架抗连续倒塌性能进行分析研究,利用软件SAP2000.V15.0.1,建立了 22mx18m,层高16m的典型钢筋混凝土框架结构模型,进行传统钢筋加固和SFCB筋加固下结构性能的对比;根据相关SFCB筋材性能研究,确定软件中力学性能的调整系数,以更接近筋材的实际情况;利用备用路径法对模型分别进行角柱,中柱,内柱拆除的三种情况,对剩余结构抗连续倒塌性能进行分析研究,得到不同同情况的下的结论;研究SFCB筋二次刚度和塑性铰旋转能力对结构抗连续倒塌的影响,在软件中,通过调整系数的方法,不断提高二次刚度和塑性铰旋转能力,对比分析两种材料性能对结构的作用,得出相应结;根据所有的研究结果,对SFCB筋加固混凝土框架结构抗连续倒塌性能进行评估,并提出相关建议

关键词：连续倒塌混凝土框架结构 SFCB 二次刚度塑性铰

Investigation of the hydro-mechanical behaviour of fouled ballast

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journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第4期14卷 244-255页

作者： Yu-jun CUI Trong Vinh DUONG Anh Minh TANG jean-claude DUPLA Nicolas CALON Alain ROBINET Laboratoire Navier/CERMES Ecole des Ponts ParisTechBlaise PascalCité DescartesChamps-sur-Marne 77455 Marne-la-Vallée Cedex-France French National Railway Company 93574La Plaine St DenisFrance

In this study,a fouled ballast taken from the site of Sénissiat,France,was *** the hydraulic behaviour,a large-scale cell was developed allowing drainage and evaporation tests to be carried out with monitoring of both suction and volumetric water content at various positions of the *** was observed that the hydraulic conductivity of fouled ballast is decreasing with suction increase,as for common unsaturated *** effect of fines content was found to be *** the mechanical behaviour,both monotonic and cyclic triaxial tests were carried out using a large-scale triaxial *** water contents were *** results were interpreted in terms of shear strength and permanent axial *** appeared that the water content is an important factor to be accounted for since any increase of water content or degree of saturation significantly decreases the shear strength and increases the permanent *** modelling has been attempted based on the experimental *** model in its current state is capable of describing the effects of stress level,cycle number and water content.

关键词： Fouled ballast Degree of saturation Hydraulic behaviour Mechanical behaviour Fines content Constitutive modelling