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

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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

Comparison of Two Recurrent Neural Networks for Rainfall-Runoff Modeling in the Zou River Basin at Atchérigbé (Bénin)

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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

Two-phase flow distributors for fuel cell flow channels

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Particuology 2010年第6期8卷 582-587页

作者： Hsiaotao T.Bi pierre Sauriol jürgen Stumper Clean Energy Research Centre and Department of Chemical and Biological Engineering University of British ColumbiaVancouverBCCanadaV6T 1Z4 Automotive Fuel Cell Corporation BurnabyBCCanadaV5J 5J8

All existing proton exchange membrane （PEM） fuel cell gas flow fields have been designed on the basis of single-phase gas flow distribution. The presence of liquid water in the flow causes non-uniform gas distribution, leading to poor cell performance. This paper demonstrates that a gas flow restrictor/distributor, as is commonly used in two-phase flow to stabilize multiphase transport lines and multiphase reactors, can improve the gas flow distribution by significantly reducing gas real-distribution caused by either non-uniform water formation in parallel flow channels or flow instability associated with negative-slope pressure drop characteristic of two-phase horizontal flow systems.

关键词： Gas distributor Gas-liquid two-phase flow Fuel cell flow field Pressure drop hysteresis Flow real-distribution

Challenges and prospects for consumer acceptance of cultured meat

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journal of Integrative Agriculture 2015年第2期14卷 285-294页

作者： Wim Verbeke pierre Sans Ellen j Van Loo Department of Agricultural Economics Ghent UniversityGent B-9000 Belgium INP-ENV Toulouse Toulouse 31076 France UR1303 ALISS INRA Ivry-sur-Seine 94205 France

Consumer acceptance of cultured meat is expected to depend on a wide diversity of determinants ranging from technologyrelated perceptions to product-specific expectations, and including wider contextual factors like media coverage, public involvement, and trust in science, policy and society. This paper discusses the case of cultured meat against this multitude of possible determinants shaping future consumer acceptance or rejection. The paper also presents insights from a primary exploratory study performed in April 2013 with consumers from Flanders（Belgium）（n=180）. The concept of cultured meat was only known（unaided） by 13% of the study participants. After receiving basic information about what cultured meat is, participants expressed favorable expectations about the concept. Only 9% rejected the idea of trying cultured meat, while two thirds hesitated and about quarter indicated to be willing to try it. The provision of additional information about the environmental benefits of cultured meat compared to traditional meat resulted in 43% of the participants indicating to be willing to try this novel food, while another 51% indicated to be ‘maybe＇ willing to do so. Price and sensory expectations emerged as major obstacles. Consumers eating mostly vegetarian meals were less convinced that cultured meat might be healthy, suggesting that vegetarians may not be the ideal primary target group for this novel meat substitute. Although exploratory rather than conclusive, the findings generally underscore doubts among consumers about trying this product when it would become available, and therefore also the challenge for cultured meat to mimic traditional meat in terms of sensory quality at an affordable price in order to become acceptable for future consumers.

关键词： acceptance artificial attitude consumer cultured in vitro meat synthetic

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

Biomarkers in Barrett's esophagus and esophageal adenocarcinoma:Predictors of progression and prognosis

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World journal of Gastroenterology 2010年第45期16卷 5669-5681页

作者： Chin-Ann j Ong pierre Lao-Sirieix Rebecca C Fitzgerald MRC Cancer Cell Unit Hutchison-MRC Research CentreCambridgeCB20XZUnited Kingdom

Barrett’s esophagus is a well-known premalignant lesion of the lower esophagus that is characterized by intestinal metaplasia of the squamous epithelium. It is clinically important due to the increased risk (0.5% per annum) of progression to esophageal adenocarcinoma (EA), which has a poor outcome unless diagnosed early. The current clinical management of Barrett’s esophagus is hampered by the lack of accurate predictors of progression. In addition, when patients develop EA, the current staging modalities are limited in stratifying patients into different prognostic groups in order to guide the optimal therapy for an individual patient. Biomarkers have the potential to improve radically the clinical management of patients with Barrett’s esophagus and EA but have not yet entered mainstream clinical practice. This is in contrast to other cancers like breast and prostate for which biomarkers are utilized routinely to inform clinical decisions. This review aims to highlight the most promising predictive and prognostic biomarkers in Barrett’s esophagus and EA and to discuss what is required to move the field forward towards clinical application.

关键词： Barrett’s esophagus Esophageal adenocar cinoma Esophageal dysplasia Prognosis

Unravelling the nature of Waiparaconus, a pennatulacean (Cnidaria: Octocorallia) from the Late Mesozoic-Early Cainozoic of the Southern Hemisphere

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Integrative Zoology 2014年第2期9卷 111-120页

作者： john S.BUCKERIDGE Hamish j.CAMPBELL pierre MAURIZOT Earth and Oceanic Systems Group RMIT UniversityVictoriaAustralia GNS Science Lower HuttNew Zealand BRGM The French Geological SurveyNew Caledonia

Enigmatic calcareous conical fossils have been known from marine Paleocene-Eocene sequences of New Zea-land since the early *** recently,similar fossils have been recorded from both Late Cretaceous ma-rine sequences of Western Australia,New Caledonia and Antarctica,and possibly from the Eocene of South *** present paper extends the record to the late Cretaceous of New *** remains are un-like any living taxa,and have been variously interpreted as molluscs(rudistid bivalves),cirripedes(stalked bar-nacles),annelids and inorganic *** to the Cirripedia has been refuted by Buckeridge(1983,1993),who proposed that the material would be better placed within the *** investigate this hypothe-sis in light of the New Caledonian material and by comparison with living gorgonians and pennatulaceans,and demonstrate that Waiparaconus is best placed within the *** zelandicus varies in form somewhat,with 3 morphotypes defined and reinforced by *** is provided on the imperative to fit organic remains into known groups,with reflection on what may happen if taxa are left in insertae sedis.

关键词： Cretaceous Early Paleogene pennatulacean Southern Hemisphere Waiparaconus

Phytochemical Screening, Study of Acute Toxicity and Hypoglycemic and Antihyperglycemic Activities of Silver Nanoparticles from Guibourtia tessmannii (Harms) j. Leonard (Caesalpiniaceae)

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Open journal of Applied Sciences 2024年第1期14卷 118-130页

作者： Ngoulé Charles Christian Eya’ane Meva François Sone Enone Bertin Ngo Nyobe Biwole Caroline Tankeu Séverin Elisée Songue Pascal Nguene jean pierre Etame-Loe Gisèle Department of Pharmaceutical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Biology of Plant Organisms Faculty of Sciences University of Douala Douala Cameroon

According to the World Health Organization, diabetes affects approximately 347 million people worldwide. Its management is not within the reach of all social classes, therefore medicinal plants are still the first resort for many populations in Africa. The biological material used in this study was the trunk bark of Guibourtia tessmannii. 50 g of trunk bark powder were decocted in 500 ml of distilled water for 5 minutes were carried out. The method used for the synthesis of silver nanoparticles (AgNps) was an organometallic bio-reduction of silver nitrate salts mediated by various secondary metabolites contained in the plant extract. The study of the toxicity acute was conducted according to guideline 423 of the OECD protocol. The pharmacological activities were each carried out with 28 female rats divided into 7 groups of four rats. It was a question for the hypoglycemic activity of administering various doses of silver nanoparticles and other substances to the rats thirty minutes after the carbohydrate intake and for the anti-hyperglycemic activity of administering the same substances to the rats thirty minutes before the carbohydrate intake. The extraction yield was 8.76%. Only the alkaloid test was negative. After acute toxicity study, the LD50 was greater than 2000 mg/kg. Blood sugar tests revealed that glibenclamide 5 mg/kg, which is the reference molecule, lowered blood sugar more than the other treatments applied in the other batches. It was followed by treatment with silver nanoparticles at a dose of 400 μg/kg in both tests. It was therefore concluded that silver nanoparticles from G. tessmannii are good for the formulation of improved traditional medicines and bring up their afficacity .

关键词： Guibourtia tessmannii Nanoparticles Hypoglycemia Anti-Hyperglycemia

isoAOT40:An improved ozone exposure index based on the Annual Ozone Spectrum Profile(AO3SP)

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journal of Forestry Research 2022年第6期33卷 1949-1955页

作者： Evgenios Agathokleous Costas j.Saitanis Stefanos Agathokleous Chrysanthos Savvides Vicent Calatayud pierre Sicard Collaborative Innovation Center On Forecast and Evaluation of Meteorological Disasters(CIC-FEMD) Nanjing University of Information Science&TechnologyNanjing 210044People’s Republic of China Research Center for Global Changes and Ecosystem Carbon Sequestration&Mitigation School of Applied MeteorologyNanjing University of Information Science and TechnologyNanjing 210044People’s Republic of China Lab of Ecology and Environmental Science Agricultural University of AthensIera Odos 7511855 AthensGreece The Cyprus Institute NicosiaCyprus Department of Labour Inspection Ministry of Labour and Social InsuranceNicosiaCyprus Fundación CEAM Parque TecnológicoC/Charles R.Darwin14PaternaSpain ARGANS 260 route du Pin MontardBiotFrance

Abstarct In recognition of the rising threats of groundlevel ozone(O_(3))pollution to forests,agricultural crops,and other types of vegetation,accurate and realistic risk assessment is urgently *** accumulated O_(3)exposure over a concentration threshold of 40 nmol mol-1(AOT40)is the most commonly used metric to investigate O3 exposure and its effects on vegetation and to conduct vegetation risk *** is also used by international regulatory authorities for deriving critical levels and setting standards to protect vegetation against surface O_(3).However,fixed periods of the growing season are used universally,yet growing seasons vary with latitudes and elevations,and the periods of plant lifespan also differ among annual ***,we propose the concept of the Annual O_(3)Spectrum Profile(AO_(3)SP)and apply it to calculate the profile of AOT40 throughout the year(AAOT40SP,Annual AOT40 Spectrum Profile)using the International Organization for Standardization(ISO)weeks as a shorter window ISO-based accumulated *** moving time periods of three(for crops)or six(for forests)months,the i so AOT40 behavior throughout the year can be examined as a diagnostic tool for O_(3)risks in the short-or long-term during the lifecycle of local *** this analysis,AOT40(i so AOT40)that is most representative for the local conditions and specific situations can be identified,depending on the exact growing season and lifecycle of the target *** applied this novel approach to data from five background monitoring stations located at different elevations in *** results show that the AAOT40SP approach can be used for improved and more realistic assessment of O3 risks to *** AO_(3)SP approach can also be applied using metrics other than AOT40(exposure-or flux-based),adding a new dimension to the way O_(3)risk to vegetation is assessed.

关键词： Air pollution AOT40 index Ozone risk assessment Critical levels Vegetation exposure metric