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Journal of Thermal Science 2007年第2期16卷 186-191页

作者： E.Sanz C.Nicot R.Point f.Plaza Laboratoire de Mécanique des fluides et Acoustique LMFA(ECL-UCB-INSA Lyon-CNRS)36Avenue Guy de Collongue69134 Ecully.France.

The boundary layer transition over a flat tilted plate has been studied by means of heat transfer measurements. A heat flux sensor has been developed, in order to measure the efficiency of convective heat transfer for various types of surfaces or flows. Its operation at constant temperature allows direct and fast measurements of heat flux. The present paper reports the development of the sensor and presents its application to the study of transition in a boundary layer depending on the angle of incidence of the external flow. An exponential relationship between critical Reynolds number and pressure gradient parameter has been found.

关键词： convective heat flux boundary layer transition pressure gradient.

Improving the Quality of Rubber Plants in Bagged Nurseries by the Use of Compost-Based Culture Substrates

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Open Journal of Soil Science 2021年第11期11卷 567-585页

作者： Jean Lopez Essehi Eric francis Soumahin guy fernand Yao Samuel Obouayeba Albert Yao-Kouamé National Agricultural of Research Centre Food Crop Research Station Soil Water and Plant Central Laboratory Bouaké C&#244 te d’Ivoire University Jean Lorougnon Guédé Training and Research Unit of Agroforestry Laboratory of Physiology and Plant Pathology Daloa C&#244 te d’Ivoire National Agricultural of Research Centre Research Station of Bimbresso Hevea Program Bimbresso C&#244 te d’Ivoire University félix Houphouë t-Boigny Training and Research Unit of Earth Sciences and Mineral Resources Department of Soil Sciences Abidjan C&#244 te d’Ivoire

The decrease of fertility soils, the rarity of quality potting soil used to fill nursery bags, the high cost of chemical fertilisers and the problems associated with their use are leading planters and rubber nurserymen in developing and/or expanding areas to look for alternative and sustainable fertilization. In this perspective, a trial was carried out at Research Station of CNRA-Bimbresso and in a farmer’s environment in order to evaluate the agronomic quality of compost made from chicken droppings and dry Panicum maximum straw to improve the growth of rubber plants in bagged nurseries. Mixtures based on potting soil and/or compost in different proportions were prepared. The follow-up of the trial focused on determination of the physico-chemical characteristics of the soils, measurement of the parameters of vegetative growth and the grafting success rate evaluation of rubber plants in nursery. The results obtained show that compost-based crop substrates increase soil organic matter, nitrogen, exchangeable bases, etc., in proportion to the doses applied. for the pH, the application of compost resulted in a reduction in soil acidity of about 1.3 unit compared to the initial values at the two study sites. The vegetative behaviour of the rubber plants also shows that qualitative (height and collar diameter) and quantitative (grafting success rate) improvements were recorded in the plants raised in compost-based substrates. The production of rubber plants in bagged nurseries was optimal with compost doses of 27 t⋅ha−1 (at Bimbresso, in the southeast) and 27 t⋅ha−1 combined with fractionated application of urea (at Kimoukro, in the centre), which under the conditions of the present study may be the recommended doses on rubber plants in bagged nurseries at C

关键词： Compost Soils Parameters Vegetative Growth Hevea brasiliensis Côte d’Ivoire

Quantitative Structure-Activity Relationship Study of a Benzimidazole-Derived Series Inhibiting Mycobacterium tuberculosis H37Rv

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Computational Chemistry 2022年第2期10卷 71-96页

作者： Georges Stéphane Dembélé Mamadou guy-Richard Koné fandia Konate Doh Soro Nahossé Ziao Laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan C&#244 te-d’Ivoire Groupe Ivoirien de Recherches en Modélisation des Maladies (GIR2M) Université Nangui Abrogoua Abidjan C&#244 te-d’Ivoire

This work was carried out on a series of twenty-two (22) benzimidazole derivatives with inhibitory activities against Mycobacterium tuberculosis H37Rv by applying the Quantitative Structure-Activity Relationship (QSAR) method. The molecules were optimized at the level DfT/B3LYP/6-31 + G (d, p), to obtain the molecular descriptors. We used three statistical learning tools namely, the linear multiple regression (LMR) method, the nonlinear regression (NLMR) and the artificial neural network (ANN) method. These methods allowed us to obtain three (3) quantitative models from the quantum descriptors that are, chemical potential (μ), polarizability (α), bond length l (C = N), and lipophilicity. These models showed good statistical performance. Among these, the ANN has a significantly better predictive ability R2 = 0.9995;RMSE = 0.0149;f = 31879.0548. The external validation tests verify all the criteria of Tropsha et al. and Roy et al. Also, the internal validation tests show that the model has a very satisfactory internal predictive character and can be considered as robust. Moreover, the applicability range of this model determined from the levers shows that a prediction of the pMIC of the new benzimidazole derivatives is acceptable when its lever value is lower than 1.

关键词： Mycobacterium tuberculosis H37Rv Benzimidazole Derivatives QSAR ANN Applicability Domain

Depression and Suicidal Ideations among Prisoners of the Douala Central Prison

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Open Journal of Psychiatry 2023年第3期13卷 123-135页

作者： Christian Eyoum Josephine Manga Befolo guy Jonas Basseguin Atchou guy Calvin Mbongo’O Jacques Narcisse Doumbe Olen Jean Pierre Kamga Liza Steffi Ndjeukam Bakam Audrey Divine Miyehane fulgence Léonce Kengno Kologne fabrice Minkoa Ngah félicien Ntone Enyime Ida Calixte Penda Yacouba Mapoure Njankouo Noël Emmanuel Essomba Callixte Kuate Tegueu Laquintinie Hospital Douala Cameroon faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon faculty of Medicine and Biomedical Sciences University of Yaoundé I Yaounde Cameroon

Introduction: The prison environment is a conducive environment for the development of psychiatric pathologies such as depression and suicidal ideation. To date, no related study has been conducted in Douala, Cameroon. We have therefore undertaken to study the prevalence of these pathologies and their related factors among inmates of the Douala Central Prison. Method: We conducted a cross-sectional study of 309 prisoners over a 6-month period from 1 January to 31 June 2022. This involved prisoners aged 18 years and over, who were consenting and able to read and write. Data were collected during individual interviews using a structured questionnaire. Depression was assessed by the BECK Short form Depression Inventory and suicidal ideation was assessed by the MINI. These data were processed using the SPSS version 25.0 software. The related factors were studied in bivariate and multivariate analysis. Results: Most of the prisoners were male (97%), and more than half knew their criminal status. The prevalence of depression was 33.7% and that of suicide ideation was 22.7%. Among the factors associated with depression were receiving social visits and suicidal ideation. A history of physical/psychological abuse, repeated offences and prison violence were protective factors. factors associated with suicidal ideation were the absence of social visits, physical abuse in childhood, smoking in prison and depression. Suicidal ideation was independently associated with depression as well as depression being independently associated with suicidal ideation. Conclusion: About 1/3 of the prisoners had depression and almost 1/4 had suicidal ideations. As a result of this and the related factors, there is a need to reorganize psychiatric care within our prison context.

关键词： Depression Suicidal Ideation Prevalence

Evaluation of SON’OR^(█),a Medical Device for Provoked Otoacoustic Emissions and Brainstem Evoked Response Audiometry Made in Cameroon

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Journal of Biomedical Science and Engineering 2017年第8期10卷 376-389页

作者： Jean Espoir E.Vokwely Jean Valentin f.fokouo guy Merlin Ngounou Dalil Asmaou Esthelle G.Minka Ngom Martin Kom Richard L.Njock G.Bengono Alexis Ndjolo Otorhinolaryngology Service Centre Hospitalier d’EssosYaoundeCameroon Regional Hospital Bertoua BertouaCameroon National Advanced School of Engineering YaoundeCameroon BENDO Company YaoundeCameroon General Hospital YaoundeCameroon General Hospital DoualaCameroon Laquintinie Hospital DoualaCameroon Cameroon Society of Otolaryngology and Head and Neck Surgery YaoundeCameroon Chantal Biya International Research Center YaoundeCameroon

Background: There is a huge gap in the audiological care in Africa by comparison with Western countries. Its main reason is the prohibitive cost of the medical devices used to screen or diagnose patients. A Cameroonian team tackled this problem by developing a medical device (SON’OR©) which integrates a new instrumentation amplifier structure dedicated to perform otoacoustic emissions (OAE) and brainstem evoked response audiometry (BERA). The major technical challenges to perform OAE and BERA are the synchronization and the amplification of signals of very low amplitude. In this work, we emphasize on the general criteria necessary and indispensable to achieve an optimal amplification. The application of a novel instrumentation amplifier structure characterized by its optimized noise factor in the case of BERA and OEA emissions provides simulations and experimental results fully in line with forecasts. The design of SON’OR©is based on general techniques of electronic instrumentation to which we associated the new instrumentation amplifier structure. Objective: To report the clinical evaluation of SON’OR©as a screening and diagnostic tool. Methods: We conducted a cross sectional comparative study in Centre Hospitalier d’Essos in Yaoundé. We tested SON’OR©on two sets of subjects, one for OAE with OTODYNAMICS Echoport ILO 292-II as gold standard and the other for BERA with NEUROSOfT NEURO AUDIO©as gold standard. Each patient was tested with both devices and then we studied the inter device differences and calculated the sensitivity, specificity, positive predictive value and negative predictive value for each test. Results: We got 52 subjects for OEA and 51 for BERA testing. Sex ratio was 1 woman for 2 men in both groups. Mean age was 24.86(SD = 10.53) and 26.33 (10.55) for OAE and BERA groups respectively. SON’OR©had good performances, showing sensitivity of 92.85%/95%, specificity of 96.77%/90.47%, positive predictive value of 95.21%/93.4

关键词： SON’OR^(█) Brainstem Evoked Response Audiometry Otoacoustic Emissions Cameroon Neonatal Hearing Screening

Development of Predictive QSPR Model of the first Reduction Potential from a Series of Tetracyanoquinodimethane (TCNQ) Molecules by the DfT (Density functional Theory) Method

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Computational Chemistry 2019年第4期7卷 121-142页

作者： fatogoma Diarrassouba Mawa Koné Kafoumba Bamba Yafigui Traoré Mamadou guy-Richard Koné Edja florentin Assanvo Laboratoire de Thermodynamique et de Physico-chimie du Milieu UFR-SFA Université Nangui Abrogoua Abidjan Côte d’Ivoire Laboratoire de Chimie Organique et des Substances Naturelles UFR-SSMT Université Félix Houphouët Boigny Abidjan Côte d’Ivoire

In this work, which consisted to develop a predictive QSPR (Quantitative Structure-Property Relationship) model of the first reduction potential, we were particularly interested in a series of forty molecules. These molecules have constituted our database. Here, thirty molecules were used for the training set and ten molecules were used for the test set. for the calculation of the descriptors, all molecules have been firstly optimized with a frequency calculation at B3LYP/6-31G(d,p) theory level. Using statistical analysis methods, a predictive QSPR (Quantitative Structure-Property Relationship) model of the first reduction potential dependent on electronic affinity (EA) only have been developed. The statistical and validation parameters derived from this model have been determined and found interesting. These different parameters and the realized statistical tests have revealed that this model is suitable for predicting the first reduction potential of future TCNQ (tetracyanoquinodimethane) of this same family belonging to its applicability domain with a 95% confidence level.

关键词： Tetracyanoquinodimethane first Reduction Potential QSPR Statistical Analysis

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加快国际税务争端解决:新西兰的视角

国际税收 2019年第5期 8-12页

作者：约翰.纳什陈延忠新西兰税务局厦门海事法院海商庭最高人民法院中国应用法学研究所

—、导言新西兰与世界其他国家一样,在日益增长的跨境活动中占有一席之地。因此,新西兰和其他管辖区必须制定切实有效的程序,加快解决关于征税权分配的国际争端。税收协定则为解决缔约国主管当局之间的双边争端提供了平台。

关键词：国际争端新西兰争端解决税务管辖区征税权缔约国跨境

DfT Study, Linear and Nonlinear Multiple Regression in the Prediction of HDAC7 Inhibitory Activities on a Series of Hydroxamic Acids

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Computational Molecular Bioscience 2019年第3期9卷 63-80页

作者： Doh Soro Lynda Ekou Bafétigué Ouattara Mamadou guy-Richard Kone Tchirioua Ekou Nahossé Ziao Laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan C&#244 te-d’Ivoire Laboratoire de Physique fondamentale et Appliquée Université Nangui Abrogoua C&#244 te d’Ivoire

In this work, we conducted a QSAR study on 18 molecules using descriptors from the Density functional Theory (DfT) in order to predict the inhibitory activity of hydroxamic acids on histone deacetylase 7. This study is performed using the principal component analysis (PCA) method, the Ascendant Hierarchical Classification (AHC), the linear multiple regression method (LMR) and the nonlinear multiple regression (NLMR). DfT calculations were performed to obtain information on the structure and information on the properties on a series of hydroxamic acids compounds studied. Multivariate statistical analysis yielded two quantitative models (model MLR and model MNLR) with the quantum descriptors: electronic affinity (AE), vibration frequency of the OH bond (ν(OH)) and that of the NH bond (ν(NH)). The LMR model gives statistically significant results and shows a good predictability R2 = 0.9659, S = 0.488, f = 85 and p-value . Electronic affinity is the priority descriptor in predicting the activity of HDAC7 inhibitors in this study. The results obtained suggest that the descriptors derived from the DfT could be useful to predict the activity of histone deacetylase 7 inhibitors. These models were evaluated according to the criteria of Tropsha et al.

关键词： Hydroxamic Acids Histones Deacetylases DfT Histones Deacetylases Inhibitors QSAR

25 Gbps low-voltage hetero-structured silicongermanium waveguide pin photodetectors for monolithic on-chip nanophotonic architectures

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Photonics Research 2019年第4期7卷 437-444页

作者： DANIEL BENEDIKOVIC LéOPOLD VIROT guy AUBIN fARAH AMAR BERTRAND SZELAG BAYRAM KARAKUS JEAN-MICHEL HARTMANN CARLOS ALONSO-RAMOS XAVIER LE ROUX PAUL CROZAT ERIC CASSAN DELPHINE MARRIS-MORINI CHARLES BAUDOT fRéDéRIC BOEUf JEAN-MARC féDéLI CHRISTOPHE KOPP LAURENT VIVIEN Centre de Nanosciences et de Nanotechnologies CNRS University of Paris-Sud Université Paris-Saclay University Grenoble Alpes and CEA LETI Minatec Campus Technology R&D STMicroelectronics SAS

Near-infrared germanium(Ge) photodetectors monolithically integrated on top of silicon-on-insulator substrates are universally regarded as key enablers towards chip-scale nanophotonics, with applications ranging from sensing and health monitoring to object recognition and optical communications. In this work, we report on the highdata-rate performance pin waveguide photodetectors made of a lateral hetero-structured silicon-Ge-silicon(Si-Ge-Si) junction operating under low reverse bias at 1.55 μm. The pin photodetector integration scheme considerably eases device manufacturing and is fully compatible with complementary metal-oxide-semiconductor technology. In particular, the hetero-structured Si-Ge-Si photodetectors show efficiency-bandwidth products of^9 GHz at-1 V and ~30 GHz at-3 V, with a leakage dark current as low as ~150 nA, allowing superior signal detection of high-speed data traffic. A bit-error rate of 10-9 is achieved for conventional 10 Gbps, 20 Gbps, and25 Gbps data rates, yielding optical power sensitivities of-13.85 dBm,-12.70 dBm, and-11.25 dBm, respectively. This demonstration opens up new horizons towards cost-effective Ge pin waveguide photodetectors that combine fast device operation at low voltages with standard semiconductor fabrication processes, as desired for reliable on-chip architectures in next-generation nanophotonics integrated circuits.

关键词： germanium(Ge) photodetectors chip-scale nanophotonics waveguide photodetectors

Quantitative Structure Anti-Cancer Activity Relationship (QSAR) of a Series of Ruthenium Complex Azopyridine by the Density functional Theory (DfT) Method

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Computational Molecular Bioscience 2017年第2期7卷 19-31页

作者： Kouakou Nobel N’guessan Mamadou guy-Richard Koné Kafoumba Bamba Ouattara Wawohinlin Patrice Nahossé Ziao Laboratoire de Thermodynamique et de Physico-Chimie du Milieu UFR SFA Université Nangui Abrogoua Abidjan C&ocircte-d’Ivoire

A series of ruthenium azopyridine complexes have recently been investigated due to their potential cytotoxic activities against renal cancer (A498), lung cancer (H226), ovarian cancer (IGROV), breast cancer (MCf-7) and colon cancer (WIDR). Thus, in order to predict the cytotoxic potentials of these compounds, quantitative structure-activity relationship studies were carried out using the methods of quantum chemistry. five Quantitative Structure Activity Relationship (QSAR) models were obtained from the determined quantum descriptors and the different activities. The models present the following statistical indicators: regression correlation coefficient R2 = 0.986 - 0.905, standard deviation S = 0.516 - 0.153, fischer test f = 106.718 - 14.220, correlation coefficient of cross-validation = 0.985- 0.895 and = 0.010 - 0.001. The statistical characteristics of the established QSAR models satisfy the acceptance and external validation criteria, thereby accrediting their good performance. The models developed show that the variation of the free enthalpy of reaction , the dipole moment μ and the charge of the ligand in the complex Ql, are the explanatory and predictive quantum descriptors correlated with the values of the anti-cancer activity of the studied complexes. Moreover, the charge of the ligand is the priority descriptor for the prediction of the cytotoxicity of the compounds studied. furthermore, QSAR models developed are statistically significant and predictive, and could be used for the design and synthesis of new anti-cancer molecules.

关键词： Ruthenium Azopyridine Complex Anti-Cancer QSAR DfT Method