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journal of Geoscience and Environment Protection 2024年第9期12卷 167-181页

作者： Iboukoun Eliézer Biao Oscar Houessou pierre jérôme Zohou Adéchina Eric Alamou National School of Mathematical Engineering and Modeling National University of Sciences Technology Engineering and Mathematics Abomey Benin LaGEA National School of Public Works National University of Sciences Technology Engineering and Mathematics Abomey Benin International Chair of Mathematical Physics and Applications (ICMPA-UNESCO Chair) University of Abomey-Calavi Abomey-Calavi Bnin

Hydrological models are developed to simulate river flows over a watershed for many practical applications in the field of water resource management. The present paper compares the performance of two recurrent neural networks for rainfall-runoff modeling in the Zou River basin at Atchérigbé outlet. To this end, we used daily precipitation data over the period 1988-2010 as input of the models, such as the Long Short-Term Memory (LSTM) and Recurrent Gate Networks (GRU) to simulate river discharge in the study area. The investigated models give good results in calibration (R2 = 0.888, NSE = 0.886, and RMSE = 0.42 for LSTM;R2 = 0.9, NSE = 0.9 and RMSE = 0.397 for GRU) and in validation (R2 = 0.865, NSE = 0.851, and RMSE = 0.329 for LSTM;R2 = 0.9, NSE = 0.865 and RMSE = 0.301 for GRU). This good performance of LSTM and GRU models confirms the importance of models based on machine learning in modeling hydrological phenomena for better decision-making.

关键词： Supervised Learning Modeling Zou Basin Long and Short-Term Memory Gated Recurrent Unit Hyperparameters Optimization

Solving the Dyson-Schwinger equation around its first singularities in the Borel plane

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Frontiers of physics 2016年第6期11卷 25-30页

作者： Clavier, pierre j. Bellon, Marc P. Sorbonne Universites UPMC Univ Paris 06 UMR 7589 LPTHE Paris France CNRS UMR 7589 LPTHE Paris France

The Dyson-Schwinger equation of the massless Wess-Zumino model is written as an equation over the anomalous dimension of the theory. Its asymptotic behavior is derived and the procedure to compute the perturbations of this asymptotic behavior is detailed. This procedure uses ill-defined objects. To solve this, the Dyson-Schwinger equation is rewritten for the Borel plane. It is shown that the ill- defined procedure in the physical plane can be applied in the Borel plane. Other results obtained in the Borel plane are stated and the proof for one result is described.

关键词： Dyson-Schwinger equation Wess-Zumino model Borel transform

Flexible visualization framework for head-mounted display with gesture interaction interface

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International journal of Modeling, Simulation, and Scientific Computing 2018年第3期9卷 22-41页

作者： pierre j.jarsaillon Naohisa Sakamoto Akira Kageyama Computer Science Department INSA Lyon 20 avenue Albert EinsteinVilleurbanne Cedex 69621France Graduate School of System Informatic Kobe University 1-1 Rokko-daiNada-ku Kobe 657-8501Japan Department of Computational Science Kobe University 1-1 Rokko-dai Nada-kuKobe 657-8501Japan

As the development of new visualization systems,within the field of simulation,offers their users more insights from their simulations,immersive systems are becoming a part of the visualization *** the recent advancements of the Head-Mounted Displays(HMDs)and popularity of motion sensors,human beings and computer become more *** study aims to evaluate the potential of such systems as a visualization tool through the development of a new flexible framework for visualization within virtual reality(VR)environment,using an Oculus Rift and a Leap *** approaches are then compared:high-3D object rendering within the virtual scene approach and a user experience-oriented system with an intuitive *** assess the quality of the interface and its relevance for the user,different types of gestures are implemented and *** an experiment on users to evaluate the developed system as a proper visualization tool,the HMDs,paired with a motion sensor to make a gesture-controlled interface seem to be promising mediums despite various constraints on development regarding the technology limitations.

关键词： Virtual reality motion sensor interactive tool user experience immersive visualization.

Competition for food in 2 populations of a wild-caught fish

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Current Zoology 2018年第5期64卷 615-622页

作者： pierre j.C. CHUARD Grant E. BROWN james W.A. GRANT Research School of Biology The Australian National University Canberra ACT 0200 Australia Departmentof Biology Concordia University 7141 Sherbrooke Street West Montreal Quebec Canada H4B 1R6

Aggressive behavior when competing for resources is expected to increase as the ratio of competitors-to-resource ratio （CRR） units increases. Females are expected to be more aggressive than males when competing for food when body size is more strongly related to reproductive suc- cess in females than in males, whereas aggression is predicted to decrease under high ambient predation risk by natural selection. Under the risk allocation model, however, individuals under high ambient predation risk are expected to be more aggressive, and forage more in the absence of imminent risk than their low risk counterparts. An interaction between adult sex ratio （i.e., adult males/females）, ambient predation risk （high vs. low）, and sex on intrasexual competition for mates in Trinidadian guppies Poecilia reticulata has been shown. The interaction suggested an increase in aggression rates as CRR increased, except for males from the high predation population. To compare the patterns of competition for food versus mates, we replicated this study by using food patches. We allowed 4 male or 4 female guppies from high and low predation populations to com- pete for 5, 3, or 1 food patches. The foraging rate was higher in a high rather than low ambient pre- dation risk population. Surprisingly, CRR, sex, and population of origin had no effect on aggression rates. Despite other environmental differences between the 2 populations, the effect of ambient predation risk may be a likely explanation for differences in foraging rates. These results highlight the importance for individuals to secure food despite the cost of competition and predation.

关键词： aggression competitor-to-resource ratio foraging Poecifia reticulata population differences predation risk sex

Local predation risk shapes spatial and foraging neophobia patterns in Trinidadian guppies

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Current Zoology 2016年第5期62卷 457-462页

作者： Chris K. ELVIDGE pierre j.C. CHUARD Grant E. BROWN Department of Biology Concordia University 7141 Sherbrooke St. West Montreal QC H4B 1R6 Canada

The ＂dangerous niche＂ hypothesis posits that neophobia functions to reduce the cost of habitat use among animals exposed to unknown risks. For example, more dangerous foraging or higher competi- tion may lead to increased spatial neophobia. Likewise, elevated ambient predation threats have been shown to induce phenotypically plastic neophobic predator avoidance. In both cases, neophobia is argued to reduce the cost of living associated with ecological uncertainty. Here, we test the hypothesis that ambient predation shapes both neophobic predator avoidance and spatial and foraging neophobia in Trinidadian guppies. Guppies were exposed to a novel foraging arena paired with a known cue （conspecific alarm cue）, a novel cue （lemon odor）, or a stream water control in three streams differing in ambient predation risk. We demonstrate that guppies from a high-predation-risk stream exhibited risk-averse foraging patterns regardless of the chemical stimulus presented （high spatial neophobia） and that those from a low-predation-risk stream were only risk-averse when the foraging arenas were paired with conspecific alarm cue （lower spatial neophobia）. Those tested in the intermediate- predation-risk stream were consistently intermediate to the high-risk vs. low-risk populations. Our study suggests that ambient predation risk shapes both neophobic predator avoidance and space-use pat- terns and that neophobia may function as a ＂generalized＂ response to ecological uncertainty.

关键词： phenotypic plasticity predator recognition foraging predator recognition predator-prey interactions Trinidadian guppies.

Determination and assessment of total mercury levels in local, frozen and canned fish in Lebanon

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journal of Environmental Sciences 2011年第9期23卷 1564-1569页

作者： pierre j Obeid Bilal El-Khoury joanne Burger Samer Aouad Mira Younis Amal Aoun john Hanna El-Nakat University of Balamand Faculty of SciencesDepartment of Chemistry Nelson Biological Laboratory Division of Life SciencesRutgers University

Fish is an important constituent of the Lebanese ***,very little attention in our area is given to bring awareness regarding the effect of the toxicity of mercury （Hg） mainly through fish *** study aimed to report analytical data on total mercury levels in several fish species for the first time in thirty years and to also made individuals aware of the presence and danger from exposure to mercury through fish *** samples were selected from local Lebanese markets and fisheries and included 94 samples of which were fresh,frozen,processed,and canned *** values were reported as microgram of mercury per gram of fish based on wet *** level of mercury ranged from 0.0190 to 0.5700 μg/g in fresh samples,0.0059 to 0.0665 μg/g in frozen samples,and 0.0305 to 0.1190 μg/g in canned *** data clearly showed that higher levels of mercury were detected in local fresh fish as opposed to other types thus placing consumers at higher risk from mercury ***,the data revealed that Mallifa （yellowstripe barracuda/Sphyraena chrysotaenia）,Sargous （white seabream/Diplodus sargus）,Ghobbos （bogue/Boops boops）,and shrimp （Penaeus sp.） were among the types containing the highest amounts of *** the other hand,processed fish such as fish fillet,fish burger,small shrimp and crab are found to contain lower levels of mercury and are associated with lower exposure risks to *** population should therefore,be aware to consume limited amounts of fresh local fish to minimize exposure to mercury.

关键词： total mercury fish Lebanon

Tumor-associated methylation of the putative tumor suppressor AjAP1 gene and association between decreased AjAP1 expression and shorter survival in patients with glioma

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Chinese journal of Cancer 2011年第4期30卷 247-253页

作者： David Cogdell Woonbok Chung Yuexin Liu j. Matthew McDonald Kenneth Aldape jean-pierre j. Issa Gregory N. Fuller Wei Zhang Department of Pathology The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA Department of Leukemia The University of Texas MD Anderson Cancer Center Houston Texas 77030 USA.

Allelic loss of the short arm of chromosome 1 has been observed frequently in a wide spectrum of cancers,most frequently in *** our previous studies,we evaluated 177 oligodendroglial tumor samples and identified the AjAP1 gene(formerly Shrew1) in the consensus region of ***1 is a transmembrane protein found in adheren junctions and functions to inhibit glioma cell adhesion and *** a putative tumor suppressor gene,we did not detect AjAP1 gene *** subsequent studies,we found that AjAP1 was underexpressed in oligodendrogliomas relative to normal brain *** analysis revealed the presence of CpG islands in the promoter of *** analysis of the AjAP1 promoter identified hypermethylation in 21% of oligodendrogliomas(n = 27),and the degree of methylation correlated with low levels of AjAP1 expression(P = 0.045).The AjAP1 promoter was also highly methylated in a wide spectrum of cell lines(n = 22),including cell lines of *** of the National Cancer Institute's REMBRANDT dataset,which contains 343 glioma samples,indicated that low AjAP1 gene expression was associated with decreased ***,both genetic(gene deletion) and epigenetic alterations(promoter methylation) are likely mechanisms that inactivate the putative tumor suppressor AjAP1 in gliomas,which contributes to poor prognosis.

关键词：甲基化分析脑胶质瘤抑癌基因 P1基因肿瘤患者协会少突胶质细胞

Neuron-glia metabolic coupling:relevance for neuronal plasticity and functional brain imaging

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Neuron-glia metabolic coupling:relevance for neuronal plasti...

In vitro and in vivo models used to study bone metabolism

中国生理学会第24届全国会员代表大会暨生理学学术大会

作者： pierre j.Magistretti University of Lausanne Division of Biological and Environmental Sciences and Engineering KAUSTThuwalKSA Brain Mind Intsitute EPFLLausanneSwitzerlandMDPhD

＜正＞A tight metabolic coupling between astrocytes and neurons is a key feature of brain energy metabolism（Allaman et al 2011;Bélanger et al 2011）.Over the years we have described two basic mechanisms of neurometabolic *** the glycogenolytic effect of VIP-restricted to cortical columns-and of noradrenaline-spanning across functionally distinct cortical areas-indicating a regulation of brain

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In vitro and in vivo models used to study bone metabolism

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

第十五届国际药理学大会

作者： pierre j.Marie Inserm U606 and University Paris 7 Hopital Lariboisiere Paris France

＜正＞ Several in vitro and in vivo models proved to be useful to study bone cell metabolism. In vitro, bone formation and bone resorption activity can be analysed using organ cultures of calvaria or long bones. Bone cell proliferation, differentiation, apoptosis, and the osteogenic and resorptive capacity can be tested using osteoblastic or osteoclastic cell cultures. Ex-vivo cultures of bone cells allow to compare in vivo and in vitro cell phenotypes. Useful in vivo models of bone loss include ovariectomy, immobilization, glucocorticoid treatment and protein/mineral deficiency. Multiple models of transgenic （TG） and knock-out （KO） mice were developped. Most relevant models are LRP5, Wnt, leptin, RANKL and OPG TG/KO which show altered bone mass, microarchitecture and resistance （analysed by BMD, micro-CT. biomechanics）, and altered cell activity （measured by histomorphometry, ex-vivo cultures, gene expression）. In humans, analysis of patients with genetic mutations causing increased bone formation or bone mass were also shown to be useful. These models may allow to identify novel mechanisms that control bone metabolism and to develop new treatments for osteoporosis.

关键词： Bone metabolism osteoblast osteoclast

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien G.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error