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Neural Regeneration Research 2019年第1期14卷 24-33页

作者： Martial Caillaud Laurence Richard Jean-Michel Vallat Alexis Desmoulière fabrice Billet University of Limoges Myelin Maintenance and Peripheral Neuropathies Faculties of Medicine and Pharmacy University Hospital of Limoges Department of Neurology "Reference Center for Rare Peripheral Neuropathies" Department of Neurology

Peripheral nerves are particularly vulnerable to injuries and are involved in numerous pathologies for which specific treatments are lacking. This review summarizes the pathophysiological features of the most common traumatic nerve injury in humans and the different animal models used in nerve regeneration studies. The current knowledge concerning Wallerian degeneration and nerve regrowth is then described. Finally, the involvement of intraneural vascularization in these processes is addressed. As intraneural vascularization has been poorly studied, histological experiments were carried out from rat sciatic nerves damaged by a glycerol injection. The results, taken together with the data from literature, suggest that revascularization plays an important role in peripheral nerve regeneration and must therefore be studied more carefully.

关键词：神经生长新生动物模型 Ihe 组织学损害学习老鼠

Quantitative Analysis of the Sized Ranged Plastic Debris on Beach Shoreline along the Limbe Coastline, Cameroon

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Journal of Environmental Protection 2023年第6期14卷 441-469页

作者： Eric Esongami Ndumbe Veronica Ebot Manga Josepha Tendo Foba fabrice Lamfu Yengong Department of Environmental Science Faculty of Science University of Buea P.O. Box 63 Molyko-Buea Cameroon Department of Chemistry Faculty of Science University of Buea P.O. Box 63 Molyko-Buea Cameroon

In recent years, increased interest in investigating the accumulation of sized ranged plastic debris has been observed on beaches along coastlines. The abundance and distribution of the 4M’s sized class plastic debris were quantitatively assessed on five sandy beaches, in Cameroon. Duplicates of 2 × 2 m (4 m2) quadrants were sampled in each beach/month with a total of 80 quadrants. Collected plastic samples were washed, sieved and dried. Particles of size, ≥2 mm, were sorted and measured using a 30 cm ruler, and converted to mm. Overall, 12,822 particles by number (530.59 g) with a mean abundance of 40.07 items/m2 (1.66 g/m2) plastic debris was recorded. ANOVA (p = 0.05) shows a linear relationship between the meso- and micro-sized classes with significantly higher abundance recorded in LDB sites. The highest abundance by weight was recorded in August and June numerically. 80% of the plastic particles were between the size range, of 5 - 20 mm by number and 6 - 100 mm by weight. Moreover, in all beaches micro-sized class plastics were dominated by number 42.40% with fragmented debris dominant, in number/weight, 54.86% (25.69%) while meso-sized class plastics were 29.28% dominated by weight, with fragmented debris type, the most prevalence in number and weight as 46.11% (26.18%). On average, color and shape fractions revealed, colored and irregularly shaped plastics were dominant with an abundance of 80.45 ± 18.17 items/m2 (2.58 ± 0.68 g/m2) and 47.24 ± 20.40 items/m2 (1.39 ± 0.66 g/m2). Finally, the 0.0001 g plastic debris was dominant with a concentration, of 33.68 ± 7.23 items/m2. The intense use of beaches for recreation and poor waste disposal has increased the potential for plastic contamination.

关键词： Plastic Debris Beach Size-Ranged Class 4M’s Abundance Cameroon

Monolithic crystalline silicon solar cells with SiN_x layers doped with Tb^(3+) and Yb^(3+) rare-earth ions

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Journal of Rare Earths 2019年第5期37卷 515-519页

作者： Ing-Song Yu Shao-Chun Wu Lucile Dumont Julien Cardin Christophe Labbé fabrice Gourbilleau Department of Materials Science and Engineering National Dong Hwa University CIMAP CNRS/CEA/ENSICAEN/Université de Caen Normandie

In this study, we propose the fabrication of monolithic crystalline silicon solar cells with Tb^(3+) and Yb^(3+)-doped silicon nitride(SiN_x) layers by low-cost screen-printing methods. The performances of c-Si solar cells can be enhanced by rare-earth ions doped SiN_x layers via the mechanism of spectrum *** SiN_x doped and codoped thin films were deposited by reactive magnetron co-sputtering and integrated as the antireflection coating layers in c-Si solar cells. The characterizations of SiN_x, SiN_x:Tb^(3+) tand SiN_x:Tb^(3+)-Yb^(3+) thin films were conducted by means of photoluminescence, Rutherford backscattering spectroscopy, Ellipsometry spectroscopy and Fourier transform infrared measurements. Their composition and refractive index was optimized to obtain good anti-reflection coating layer for c-Si solar *** electron microscopy performs the uniform coatings on the textured emitter of c-Si solar cells. After the metallization process, we demonstrate monolithic c-Si solar cells with spectrum conversion layers, which lead to a relative increase by 1.34% in the conversion efficiency.

关键词： Crystalline silicon solar cell Spectrum conversion Silicon nitride Down-shifting Rare-earth ion Anti-reflection coating

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铌在碳酸岩浆体系中的溶解度实验研究

铌在碳酸岩浆体系中的溶解度实验研究

Two-dimensional modeling of fine sediment transport with mixed sediment and consolidation: Application to the Gironde Estuary,France

第十届全国成矿理论与找矿方法学术讨论会

作者：许雅婷 fabrice Gaillard 王汝成南京大学地球科学与工程学院内生金属矿床国家重点实验室地球关键物质循环研究中心

铌(Nb)是一种关键稀有金属,对现代社会的高科技产业具有重要价值。碳酸岩是Nb的重要来源,烧绿石(Pyrochlore)是碳酸岩中重要的赋铌矿物,而碳酸岩中烧绿石的成矿属于岩浆过程还是热液过程一直是热议的研究主题。Nb在碳酸岩岩浆中的溶解...

铌(Nb)是一种关键稀有金属,对现代社会的高科技产业具有重要价值。碳酸岩是Nb的重要来源,烧绿石(Pyrochlore)是碳酸岩中重要的赋铌矿物,而碳酸岩中烧绿石的成矿属于岩浆过程还是热液过程一直是热议的研究主题。Nb在碳酸岩岩浆中的溶解度相关的现有研究不多,本文通过高温高压实验方法,探究了Nb在碳酸岩浆体系中的溶解度,为研究烧绿石在此类岩浆系统中的结晶成矿过程提供了新的见解。

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International Journal of Sediment Research 2021年第6期36卷 736-746页

作者： Sylvain Orseau Nicolas Huybrechts Pablo Tassi Damien Pham Van Bang fabrice Klein Cerema Direction Technique Eau Mer et Fleuves Sorbonne Universités Université de Technologie de Compiégne CNRSFRE2012 RobervalCentre de Recherche Royallieu Electricité de France R&D Department Laboratoire d'Hydraulique Saint Venant (ENPC-EDF/R&D-CEREMA) 5. Centre Eau Terre et Environnement INRS-ETE 6. Grand Port Maritime de Bordeaux

In order to optimize ship navigation in the macrotidal Gironde Estuary, a recent project funded by the port of Bordeaux aims at better understand and forecast hydrodynamic and fine sediment transport within the estuary. In the framework of this project, a two-dimensional hydro-sedimentary model is built. The model includes hydrodynamic forcings, mixed-sediment transport, and consolidation processes. The harmonic analysis of the astronomical tides reveals a strong distortion of the tidal wave inducing the growth of overtide constituents and the non-significant effect of tide-surge interactions in annual-scale prediction. Depending on hydrological conditions, river discharge can considerably alter the model accuracy due to the migration of the turbidity maximum zone modifying the bottom *** with measurements shows the ability of the model to reproduce suspended-sediment concentrations in the central Estuary. Sensitivity of the model to sediment features has also been discussed in regard of suspended-sediment concentrations and fluid mud deposits. The model will be further coupled with ship squat predictions and a morphodynamic model.

关键词： Sediment transport Numerical modeling Mixed sediment Gironde Estuary Opentelemac

Comparing Machine Learning Algorithms for Improving the Maintenance of LTE Networks Based on Alarms Analysis

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Journal of Computer and Communications 2022年第12期10卷 125-137页

作者： Batchakui Bernabe Deussom Djomadji Eric Michel Chana Anne Marie Mama Tsimi Serge fabrice Department of Computer Engineering National Advanced School of Engineering UY1 Yaoundé Cameroon Department of Electrical and Telecommunications Engineering National Advanced School of Engineering Yaoundé Cameroon College of Technology University of Buea Buea Cameroon

Mobile network operators are facing many challenges to satisfy their subscribers in terms of quality of service and quality of experience provided. To achieve this goal, technological progress and scientific advances offer good opportunities for efficiency in the management of faults occurring in a mobile network. Machine learning techniques allow systems to learn from past experiences and can predict, solutions to be applied to correct the root cause of a failure. This paper evaluates machine learning techniques and identifies the decision tree as a learning model that provides the most optimal error rate in predicting outages that may occur in a mobile network. Three machine learning techniques are presented in this study and compared with regard to accuracy. This study demonstrates that the appropriate machine learning technique improves the accuracy of the model. By using the decision tree as a machine learning model, it was possible to predict solutions to network failures, with an error rate less than 2%. In addition, the use of Machine Learning makes it possible to eliminate steps in the network failure processing chain;resulting in reduced service disruption time and improved the network availability which is a key network performance index.

关键词： 4G LTE Mobile Network Machine Learning Network Maintenance Troubleshooting Decision Tree Random Forest

短暂性脱髓鞘导致长期认知障碍、髓鞘改变和神经网络同步缺陷

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神经损伤与功能重建 2024年第3期19卷 F0003-F0003页

作者： Océane Mercier Pascale P Quilichini Karine Magalon Florian Gil Antoine Ghestem fabrice Richard Thomas Boudier Myriam Cayre Pascale Durbec 杜一星(编译) UMR7288 after IBDM Aix Marseille UnivCNRSIBDMMarseilleFrance U1106 after INS Aix Marseille UnivINSERMINSInst Neurosci SystMarseilleFrance Aix Marseille Univ Turing Centre for Living SystemsMarseilleFrance 不详

在成年大脑中,活动依赖性髓鞘可塑性是正确学习和记忆巩固所必需的。因此,髓鞘的丢失、改变,甚至细微的结构变更都会损害神经网络活动,导致功能障碍。在多发性硬化症中,虽然自发的髓鞘修复过程是可能的,但患者之间存在异质性。髓鞘修复... 详细信息

在成年大脑中,活动依赖性髓鞘可塑性是正确学习和记忆巩固所必需的。因此,髓鞘的丢失、改变,甚至细微的结构变更都会损害神经网络活动,导致功能障碍。在多发性硬化症中,虽然自发的髓鞘修复过程是可能的,但患者之间存在异质性。髓鞘修复有时会导致功能恢复,这通常在运动水平比在认知水平更明显。在铜宗处理的小鼠模型中,大量脑脱髓鞘随后发生自发且强烈的髓鞘再生。然而,重组髓鞘虽然具有功能,但可能不会表现出与发育髓鞘相同的形态特征,这可能会对神经网络的活动产生影响。基于此,本研究使用铜腙处理的小鼠模型来分析短暂性脱髓鞘对脑结构、功能和认知的长期影响。本研究结果表明,尽管脱鞘事件后存在髓鞘再生,但仍会导致长期认知障碍,例如空间工作记忆、社交记忆、认知灵活性和多动症的缺陷。这些缺陷与内侧前额叶皮质(m PFC)和海马体(HPC)髓鞘含量的减少以及结构髓鞘修饰有关,表明这些结构中的髓鞘再生过程可能不完善。在体电生理记录表明,脱髓鞘事件改变了HPC-mPFC活动的同步性,这对于记忆过程至关重要。总而言之,本研究数据表明,短暂脱髓鞘后的髓鞘修复过程不允许完全恢复皮质结构中的初始髓鞘特性。这些细微的变更改变了神经网络特征并导致小鼠长期认知缺陷。

关键词：认知多发性硬化症小鼠模型髓鞘再生神经网络活动

Experimental manipulation of reproductive tactics in Seba’s short-tailed bats:consequences on sperm quality and oxidative status

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Current Zoology 2019年第6期65卷 609-616页

作者： Magali MENIRI Florence GOHON Ophelie GNING Gaetan GLAUSER Armelle VALLAT Nicolas JFASEL fabrice HELFENSTEIN Laboratory of Evolutionary Ecophysiology Institute of BiologyUniversity of NeuchatelSwitzerland Neuchatel Platform of Analytical Chemistry University of NeuchatelSwitzerland Leibniz Institute for Zoo and Wildlife Research Germany

To reproduce,males have to fertilize the female’s eggs,sometimes in competition with ejaculates of other *** species where males display alternative reproductive tactics,whereby territorial males secure mating and non-territorial males have to sneak copulations,the latter might be expected to invest relatively more resources towards sperm quality compared with the territorial *** cells are especially vulnerable to oxidative stress,which reduces male ***,antioxidant resources are expected to modulate sperm quality,and might be allocated differently between reproductive *** test the link between reproductive tactics,redox profile and sperm quality,we experimentally induced changes in the reproductive tactics of 39 captive males Seba's short-tailed bats Carollia *** monitored the blood and ejaculate oxidative balance,and the sperm quality before,7 days and 21 days after the manipulation of reproductive *** ejaculates'oxidative damage was negatively related to sperm velocity,males exhibited similar blood and ejaculates redox profiles and similar sperm quality,regardless of their reproductive ***,these results arise as a consequence of some constraints having been lifted during the *** results also suggest that,in Seba's short-tailed bats,the expression of alternative reproductive tactics is not subjected to strong oxidative ***,our results could reflect an absence of trade-off between pre-and post-copulatory traits in harem males,as they could be selected to invest both in female attraction and sperm quality,as a consequence of their inability to fully monopolize females.

关键词： oxidative stress sperm competition alternative reproductive tactics Carollia perspicillata

Long-term high fructose and saturated fat diet affects plasma fatty acid profile in rats

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第4期13卷 307-317页

作者： fabrice TRANCHIDA Léopold TCHIAKPE Zo RAKOTONIAINA Valérie DEYRIS Olivier RAVION Abel HIOL Institute of Molecular Sciences of Marseilles iSm2 UMR 7313CNRSAix-Marseille University13397 Marseilles Cedex 20France Laboratory of Nutrition-Dietetics Faculty of PharmacyAix-Marseille University13385 Marseilles Cedex 5France Food Sciences Department of Biotechnology EngineeringInstitute of TechnologyUniversity of the French West Indies and GuianaSaint-Claude 97120France

As the consumption of fructose and saturated fatty acids(FAs) has greatly increased in western diets and is linked with an increased risk of metabolic syndrome,the aim of this study was to investigate the effects of a mod-erate(10 weeks) and a prolonged(30 weeks) high fructose and saturated fatty acid(HFS) diet on plasma FA com-position in *** effects of a few weeks of HFS diet had already been described,but in this paper we tried to es-tablish whether these effects persist or if they are modified after 10 or 30 *** hypothesized that the plasma FA profile would be altered between 10 and 30 weeks of the HFS *** fed with either the HFS or a standard diet were tested after 10 weeks and again after 30 *** 10 weeks of feeding,HFS-fed rats developed the metabolic syndrome,as manifested by an increase in fasting insulinemia,total cholesterol and triglyceride levels,as well as by impaired glucose ***,the plasma FA profile of the HFS group showed higher proportions of monounsaturated FAs like palmitoleic acid [16:1(n-7)] and oleic acid [18:1(n-9)],whereas the proportions of some polyunsaturated n-6 FAs,such as linoleic acid [18:2(n-6)] and arachidonic acid [20:4(n-6)],were lower than those in the control *** 30 weeks of the HFS diet,we observed changes mainly in the levels of 16:1(n-7)(decreased) and 20:4(n-6)(increased).Together,our results suggest that an HFS diet could lead to an adaptive response of the plasma FA profile over time,in association with the development of the metabolic syndrome.

关键词： High fructose and saturated fatty acid diet Metabolic syndrome Plasma fatty acids Adaptive response Rats