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Multivariate Approach to Characterizing Soil Quality of Gabonese’s Ferralitic Soils

Open Journal of Soil Science 2024年第4期14卷 237-268页

作者： neil-Yohan Musadji Rolf Gaël Mabicka Obame Michel Mbina Mounguengui Jean Aubin Ondo Lydie-Stella Koutika Eric Ravire claude Geffroy Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement Des Sciences Fondamentales De L&#8217Ing&#233nieur Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Institut De Chimie Des Milieux et Maté riaux De Poitiers (IC2MP) Universit&#233 De Poitiers Poitiers France Laboratoire De Chimie Des Milieux et Des Mat&#233riaux Inorganiques Laboratoire D&#8217Analyse Des Sols et Environnement D&#233partement De Phytotechnologie Institut National D&#8217Agronomie et De Biotechnologies Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Dé partement De G&#233ologie Facult&#233 Des Sciences Universit&#233 Des Sciences et Techniques De Masuku Franceville Gabon Laboratoire Pluridisciplinaire Des Sciences Ecole Normale Sup&#233rieure Libreville Gabon Centre De Recherche Sur La Productivité et La Durabilit&#233 Des Plantations Industrielles Pointe Noire Republic of Congo Sucaf Gabon Somdiaa Franceville Gabon

Assessing soil quality is essential for crop management and soil temporal changes. The present study aims to evaluate soil quality in the Ferralitic soils context countrywide. This assessment was done using multivariate soil quality indice (SQI) models, such as additive quality index (AQI), weighted quality indexes (WQIadd and WQIcom) and nemoro quality index (nQI), applied to two approaches of indicator selection: total data set (TDS) and minimum data set (MDS). Physical and chemical soil indicators were extracted from the ORSTOM’s reports resulting from a sampling campaign in different provinces of Gabon. The TDS approach shows soil quality status according to eleven soil indicators extracted from the analysis of 1,059 samples from arable soil layer (0 - 30 cm depth). The results indicated that 87% of all provinces presented a very low soil quality (Q5) whatever the model. Among soil indicators, exchangeable K+ and Mg2+, bulk density and C/n ratio were retained in MDS, using principal component analysis (PCA). In the MDS approach, 50 to 63% of provinces had low soil quality grades with AQI, WQIadd and nQI, whereas the total was observed with WQIcom. Only 25% of provinces had medium soil quality grades with AQI and nQI models, while 12.5% (nQI) and 25% (AQI) presented high quality grades. Robust statistical analyses confirmed the accuracy and validation (0.80 r P ≤ 0.016) of AQI, WQIadd and nQI into the TDS and MDS approaches. The same sensitivity index value (1.53) was obtained with AQI and WQIadd. However, WQIadd was chosen as the best SQI model, according to its high linear regression value (R2 = 0.82) between TDS and MDS. This study has important implications in decision-making on monitoring, evaluation and sustainable management of Gabonese soils in a pedoclimatic context unfavorable to plant growth.

关键词： Gabon Ferralitic Soil Soil Indicators Standard Score Function Soil Quality Indices Sustainable Soil Soil Management

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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

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Green synthesis of biocompatible Gd^(3+)-doped ultrasmall carbon-based nanohybrids from coffee wastes

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Carbon Resources Conversion 2024年第2期7卷 64-73页

作者： Konstantin Paliienko Anna Topchylo Sergei Alekseev Alain Géloën Yurii Milovanov Tetiana Lysenko Valeriy Skryshevsky Tatiana Borisova Vladimir Lysenko Department of neurochemistry Palladin Institute of BiochemistryNational Academy of Sciences of Ukraine9 Leontovicha strKyiv 01054Ukraine Corporation Science Park Taras Shevchenko University of Kyiv60 Volodymyrska Str.Kyiv 01033Ukraine Institute of High Technologies Taras Shevchenko National University of Kyiv64 Volodymyrska Str.01601 KyivUkraine Faculty of Chemistry Taras Shevchenko National University of Kyiv64 Volodymyrska Str.01601 KyivUkraine UMR Ecologie Microbienne Lyon(LEM) CNRS 5557INRAE 1418Claude Bernard University of LyonVetAgro SupResearch Team“Bacterial Opportunistic Pathogens and Environment”(BPOE)University of LyonF-69622 VilleurbanneFrance Light Matter Institute UMR-5306Claude Bernard University of Lyon/CNRSUniversitéde Lyon69622 Villeurbanne CedexFrance

A cheap method allowing fabrication of biocompatible,ultra-small(2-10 nm)and fluorescent(λ_(em)=425-500 nm)nanohybrids(nHs)from coffee wastes is *** gadolinium-doped nanohybrids(GDnHs)or gadolinium-free carbon dots(GFCDs)can be synthesized in a domestic microwave oven according to green synthesis *** sizes,chemical composition,impact on proton magnetic resonance relaxation time and optical properties of the GDnHs and GFCDs were studied in details and *** particular,doping of the nHs with Gd^(3+)ions,up to 1.87%w/w of gadolinium per particles’weight,will allow their application for magnetic resonance imaging(MRI).Furthermore,cell culture tests on human adenocarcinomic alveolar basal epithelial cells line(A549)have shown high biocompatibility of the GDnHs and in a wide concentration range 100-1000μg/ml.

关键词： Carbon dots from coffee waste Carbon dots for MRI Gadolinium-doped carbon dots Microwave-assisted synthesis

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Prevalence of noise-Induced Hearing Loss Related to the Mills in the Markets of the Municipality of Parakou in 2021

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International Journal of Otolaryngology and Head & neck Surgery 2024年第1期13卷 1-10页

作者： Fatiou Alabi Bouraïma Cocouvi Bruno Ametonou Ulrich Bidossèssi Vodouhe François Avakoudjo Jorelle Wafo Marius claude Flatin Spéro H. R. Hounkpatin Wassi Adjibabi Faculty of Medicine University of Parakou Parakou Benin Faculty of Health Sciences University of Abomey-Calavi Cotonou Benin

Introduction: noise is the second leading cause of hearing loss in adults after presbycusis. The objective of this work was to study hearing loss induced by the noise of mills in the markets of Parakou. Methods: This was a descriptive and analytical cross-sectional study, conducted from February 3 to June 3, 2021 in the markets of Parakou. It concerned millers and sellers located within a 5 meter radius around the mills and among whom pure-tone audiometry was performed to detect a hearing loss. Subjects with no particular medical health history, under 55 years of age and having been working in these markets since more than 12 months, were included. Results: In this study, 103 subjects were selected, including 43 millers and 61 sellers. Their average age was 29 ± 13 years. The sex ratio was 0.49. The average length of service in the profession was 8 years with the extremes of 3 months and 47 years. They were exposed to noise on average 10 hours per day and 6 days a week. The average duration of weekly noise exposure was 23 h 28 min ± 13 h 32 min with the extremes of 5 h 00 min and 52 h 30 min. The average level of noise exposure was 90 dB with the extremes of 72 and 110 dB. 24 subjects reported symptoms related to noise such as headache, tinnitus, and hearing loss, with respective proportions of 22.33%, 20.39% and 06.80%. The prevalence of noise-related hearing loss was 26.21% (n = 27/103). Subjects with a notch at 4000 Hz and normal Average Hearing Loss (AHL) (20.39%) had a seven-time greater risk of developing noise-induced hearing loss (OR = 6.58;95% CI [2.54 - 18.8], p Conclusion: Hearing loss related to the noise of mills affected both millers and sellers near the mills in markets, hence the importance of regulating mills.

关键词： noise-Induced Hearing Loss Mills Markets Parakou

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Detecting the presence of natural forests using airborne laser scanning data

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Forest Ecosystems 2023年第6期10卷 668-680页

作者： Marie-claude Jutras-Perreault Terje Gobakken Erik næsset Hans OleØrka Faculty of Environmental Sciences and natural Resource Management Norwegian University of Life SciencesNMBUP.O.BoxNO-1432ÅsNorway

Centuries of forest exploitation have caused significant loss of natural forests in Europe,leading to a decline in populations for many *** prevent further loss in biodiversity,the norwegian government has set a target of protecting 10%of the forested ***,recent data from the national Forest Inventory(nFI)reveals that less than 2%of norway's forested area consists of natural *** identify forests with high conservation value,we used vertical and horizontal variables derived from airborne laser scanning(ALS)data,along with nFI plot *** study aimed to predict the presence of natural forests across three counties in southeastern norway,using three different definitions:pristine,near-natural,and semi-natural *** forests are scarce,and their underrepresentation in field reference data can compromise the accuracy of the *** address this,we assessed the potential gain of including additional field data specifically targeting natural forests to achieve a better balance in the ***,we examined the impact of stratifying the data by dominant tree species on the performance of the *** results revealed that semi-natural forests were the most accurately predicted,followed by near-natural and pristine forests,with Matthews correlation coefficient values of 0.32,0.24,and 0.17,*** additional field data did not improve the ***,stratification by species improved the accuracy of predictions for near-natural and semi-natural forests,while reducing accuracy for pristine *** use of horizontal variables did not improve the *** study demonstrates the potential of ALS data in identifying forests with high conservation *** provides a basis for further research on the use of ALS data for the detection and conservation of natural forests,offering valuable insights to guide future forest preservation efforts.

关键词： natural forest ALS naturalness Vertical variables Horizontal variables Biodiversity Forest condition Ecosystem services

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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

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More constructions of APn and differentially 4-uniform functions by concatenation

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Science China Mathematics 2013年第7期56卷 1373-1384页

作者： CARLET claude LAGA University of Paris 13CNRS (UMR 7539)France Department of Mathematics University of Paris 8 2 rue de la liberté 93526 Saint-Denis Ced-exFrance

We study further the method of concatenating the outputs of two functions for designing an APn or a differentially 4-uniform (n, n)-function for every even n. We deduce several specific constructions of APn or differentially 4-uniform (n, n)-functions from APn and differentially 4-uniform (n/2, n/2)-functions. We also give a construction of quadratic APn functions which includes as particular cases a previous construction by the author and a more recent construction by Pott and Zhou.

关键词： block cipher vectorial function substitution box almost perfect nonlinear almost bent

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G~n filling orbicular n-sided holes using periodic B-spline surfaces

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Science China(Information Sciences) 2011年第7期54卷 1383-1394页

作者： PAUL Jean-claude School of Software Tsinghua University Key Laboratory for Information System Security Ministry of Education of China Tsinghua national Laboratory for Information Science and Technology Institute national de Recherche en Informatique et en Automatique

The orbicular n -sided hole filling problem is usually introduced by filleting an end-point of a part with large *** existing methods based on quadrilateral partition or constrained-optimization can rarely generate high-order continuous blending surfaces under these *** paper first reparameterizes the boundary of the specified orbicular n -sided hole to ensure the compatibility of neighboring cross-boundary derivatives on the connecting points,preserving their G n *** we compute the control points of the periodic B-spline surface using the sufficient G n continuity condition on the pole and the algorithm of extending parametric *** method generates single blending surface,which can be converted into standard Bspline surface by adding knots without introducing *** only elevates the degree of the boundary by *** construction method is simple and efficient,without iteration nor large-scale matrix *** achieves G n continuity under compatible *** blending examples underline its feasibility and practicability.

关键词： CAD periodic B-spline surface polar coordinates n -sided hole filling G n continuity

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On MAXWELL EQUATIOnS WITH THE TRAnSPAREnT BOUnDARY COnDITIOn

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Journal of Computational Mathematics 2008年第3期26卷 284-296页

作者： Zhiming Chen Jean-claude nédélec LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Centre de Mathématiques Appliquées Ecole Polytechnique 91228 Palaiseau Cedex France

In this paper we show the well-posedness and stability of the Maxwell scattering problem with the transparent boundary condition. The proof depends on the well-posedness of the time-harmonic Maxwell scattering problem... 详细信息

关键词： Electromagnetic scattering Well-posedness Stability

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Large Conventional Osteosarcoma of the Proximal Humerus in a 13-Year-Old Child: Case Report

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Open Journal of Pediatrics 2024年第2期14卷 297-304页

作者： Lucienne Irène Patricia Ondima Rhodia Hélène Bosseba Missengue Cardinale Princilia Okiemy niendet nuptia Erica Akobande Jean claude Mieret Caryne Mboutol-Mandavo Redy Atipo Galloye Judith nsondé Malanda Jennifer Mave Sirimé ngandzo Fabien Mouamba Faculty of Health Sciences Marien Ngouabi University Brazzaville Congo Paediatric Surgery Department Brazzaville University Hospital Centre Brazzaville Congo Department of General Surgery Brazzaville University Hospital Centre Brazzaville Congo Carcinology Department Brazzaville University Hospital Centre Brazzaville Congo Anatomo-Pathology Laboratory Brazzaville University Hospital Centre Brazzaville Congo

Introduction: Osteosarcoma is the most common primary malignant bone tumor in children. It is highly aggressive and has a poor prognosis. A late presentation modifies and makes difficult the management affecting the survival of children. We report the case of a large conventional osteosarcoma in a 13-year-old girl. Case Presentation: Adolescent girl admitted for painful swelling of the left shoulder with absolute functional impotence of the thoracic limb and severe anemia. The painful swelling was thought to have been caused by a minor trauma that had occurred six months previously. The patient’s general condition was poor, and she presented with a large, shiny, painful mass over the shoulder and upper 2/3 of the left arm, measuring 28 cm long by 28 cm wide and 57 cm in circumference, and a large fistulous axillary adenopathy. CT scan showed a tumour lesion of the left humerus with liver and lung metastases, raising suspicion of osteogenic osteosarcoma. The tumor was classified according to TnM staging: T2n1M1(a + b). Management was modified when uncontrolled bleeding developed. It consisted of an extended amputation of the left thoracic limb. Pathological analysis showed a high-grade conventional osteosarcoma. Quality improvement was obtained for thirty days, followed by the onset of dyspnea. The evolution was towards death at forty days post-operatively. Conclusion: Osteosarcoma is a highly aggressive cancer. Delayed treatment leads to a fatal outcome. Early diagnosis is one of the challenges to be met in order to improve survival.

关键词： Osteosarcoma Child Conventional Case Report

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