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Detection of functional diversity gradients and their geoclimatic filters is sensitive to data types(occurrence ***)and spatial scales(sites ***)

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Plant Diversity 2024年第6期46卷 732-743页

作者： JoséLuiz Alves Silva Alexandre Souza angela pierre vitória Laboratório de Ciências Ambientais Universidade Estadual do Norte Fluminense Darcy RibeiroCampos dos GoytacazesRio de JaneiroBrazil Departamento de Ecologia Universidade Federal do Rio Grande do NorteRio Grande do NorteBrazil

Functional diversity(FD)reflects within-and between-site variation of species traits(α-and β-FD,respectively).Understanding how much data types(occurrence-based ***-weighted)and spatial scales(sites ***)change FD and ultimately interfere with the detection of underlying geoclimatic filters is still *** contribute to this debate,we explored the occurrence of 1690 species in 690 sites,abundances of 1198 species in 343 sites,and seven functional traits of the Atlantic Forest woody flora in South *** FD indices were sensitive and dependent on the data type at both scales,with occurrence particularly increasing a richness and dispersion(occurrence>abundance in 80%of the sites)while abundance increased β total,β replacement,and α evenness(abundance>occurrence in 60%of the sites).Furthermore,detecting the effect of geoclimatic filters depended on the data type and was *** the site scale,precipitation seasonality and soil depth had weak effects on α-and β-FD(max.R^(2)=0.11).However,regional-scale patterns of a richness,dispersion,and evenness strongly mirrored the variation in precipitation seasonality,soil depth,forest stability over the last 120 kyr,and cation exchange capacity(correlations>0.80),suggesting that geoclimatic filters manifest stronger effects at the regional ***,the role of edaphic gradients expands the idea of biogeographical filters beyond *** findings caution functional biogeographic studies to consider the effect of data type and spatial scale before designing and reaching ecological conclusions about the complex nature of FD.

关键词： Environmental filtering Historical events Human pressure n-dimensional hypervolume Biodiversity hotspot Tropical forest

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Video quality based link adaptation for low latency video transmission over WLANs

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第5期7卷 847-856页

作者： FERR pierre DOUFEXI angela CHUNG-HOW James NIX Andrew BULL David University of Bristol Department of Electrical and Electronic Engineering Centre for Communications Research Bristol BS8 1UB UK ProVision Communication Technologies Bristol BS4 4EU UK

Wireless Local Area Networks (WLANs) such as IEEE 802.11a/g and Hiperlan/2 utilise numerous transmission modes, each providing different throughputs and reliability levels. Many link adaptation algorithms proposed in the literature either maximise the error-free data throughput based on channel conditions or are based on the number of failed transmissions. However, these algo- rithms do not take into account the content of the data stream and strongly rely on the use of Automatic Repeat Requests (ARQs). Low latency video applications such as real-time video transmission may require no retransmission, or only a limited number of retrans- missions. Moreover, completely error-free communication is not essential, especially if robust video compression techniques are applied. In such scenarios, improved decoded video quality can be obtained with a video stream transmitted at a higher bit rate using a higher link speed but with some degree of transmission error, rather than an error-free video stream at a lower bit rate using a lower link speed. In this work, we investigate a link adaptation scheme that improves the Quality of Service (QoS) for video transmission, based on the overall received video quality (Peak Signal to Noise Ratio, PSNR), rather than by maximising the error-free throughput. We also study a practical link adaptation approach that uses PER thresholds at the PHY layer. An empirical study showed that thresholds for switching from one mode to another are much lower (almost error free) than those currently used by throughput based schemes. We show that traditional link adaptation strategies are not appropriate for real-time video transmission with no retransmis- sion. Simulation results using the H.264 video compression standard over IEEE 802.11a are presented.

关键词： Link adaptation Wireless LAN Video quality Peak Signal to Noise Ratio (PSNR) Packet Error Rate (PER)

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Chemokine system polymorphisms, survival and hepatocellular carcinoma occurrence in patients with hepatitis C virus-related cirrhosis

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World Journal of Gastroenterology 2008年第5期14卷 713-719页

作者： pierre Nahon angela Sutton pierre Rufat Chantal Simon Jean-Claude Trinchet Liliane Gattegno Michel Beaugrand Nathalie Charnaux Department of Hepatology Jean Verdier Hospital (AP-HP) Bondy 93140 France Department of Biochemistry Jean Verdier Hospital (AP-HP) Bondy 93140 France Department of Public Health Pitié-Salpetrière Hospital (AP-HP) Paris 75013 France

AIM： To explore the influence of polymorphisms in genes encoding for the chemokines Stromal cell-Derived Factor-1 （SDF-1）/CXCL12 and Monocyte Chemotactic Protein-1 （MCP-1）/CCL2, or for the chemokine receptor CCR5 on the risks of liver-related death and hepatocellular carcinoma （HCC） occurrence in hepatitis C virus （HCV）-infected patients. METHODS： SDF-1 3＇A, MCP-1 （-2518） and CCRS-△32 polymorphisms, SDF-1α, Regulated upon Activation Normal T cells Expressed and Secreted （RANTES）/CCL5 and MCP-1 serum levels were determined in 120 HCV- infected patients, included at time of cirrhosis diagnosis and prospectively followed-up. RESULTS： During follow-up, 23/120 （19.1%） patients died and 47/120 （39.1%） developed HCC. Carriers and noncarriers of each genetic marker had similar baseline characteristics estimating the severity of liver disease. The occurrence of death or HCC during follow-up was similar among carriers and noncarriers of each polymorphism. There was no association between the carriage of mutated alleles and chemokine serum levels and the latter were not associated with the risks of death or HCC. CONCLUSION： This study suggests the lack of association of SDF-1 3＇A, MCP-1 （-2518）, CCRS-△32 polymorphisms with death and HCC occurrence in cirrhotic HCV-infected patients.

关键词： Chemokine Polymorphism Cirrhosis Hepatocarcinoma Hepatitis C virus

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Morphological integration and functional modularity in the crocodilian skull

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Integrative Zoology 2014年第4期9卷 498-516页

作者： Paolo PIRAS angela DBUSCALIONI Luciano TERESI Pasquale RAIA Gabriele SANSALONE Tassos KOTSAKIS Jorge CUBO pierre and Marie Curie University ParisFrance Center for Evolutionary Ecology RomeItaly Department of Sciences ‘Roma Tre’UniversityRomeItaly Biology Department Universidad Autónoma de MadridMadridSpain Department of Mathematics and Physics ‘Roma Tre’UniversityRomeItaly Earth Sciences Department Federico II UniversityNaplesItaly Sorbonne Universités UPMC Univ Paris 06UMR 7193ISTePFrance CNRS UMR 7193ISTePParisFrance

We explored the morphological organization of the skull within Crocodylidae,analyzing functional and phylogenetic interactions between its 2 constituent functional modules:the rostrum and the *** used geometric morphometrics to identify localized shape changes,focusing on the differences between the major clades of the crown-group Crocodylia:Alligatoridae and *** used published bite performance data to correlate rostral function with postrostral *** skull modules appear more integrated within Alligatoridae than within *** effects on shape variation are more evident in Alligatoridae than in Crocodylidae,where functional parameters concerning the rostral morphology are proportionally more important than ***-snouted species are characterized by low structural performance,which is significantly associated with a reduction of the pterygoid-quadrate cranial nipper,suggesting that the nipper is important for the ingestion of large food items in generalist *** functional association is coupled with a significant evolutionary allometry at the clade level,while Alligatoridae and Crocodylidae show different degrees of evolutionary allometry for their entire shape and *** postrostrum is more conservative than the rostrum in terms of morphospace occupation,evolutionary allometry and phylogenetic signal.

关键词： crocodilian skull functional performance geometric morphometrics modularity morphological integration

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High-capacity free-space optical link in the midinfrared thermal atmospheric windows using unipolar quantum devices

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Advanced Photonics 2022年第5期4卷 36-46页

作者： pierre Didier Hamza Dely Thomas Bonazzi Olivier Spitz Elie Awwad Étienne Rodriguez angela Vasanelli Carlo Sirtori Frédéric Grillot Télécom Paris Institut Polytechnique de ParisLTCIPalaiseauFrance mirSense Centre d’integration NanoInnovPalaiseau France ENS UniversitéPSLCNRSSorbonne UniversitéUniversitéde ParisLaboratoire de Physique de l’École Normale SupérieureParisFrance University of Central Florida CREOLCollege of Optics and PhotonicsOrlandoFloridaUnited States University of New Mexico Center for High Technology MaterialsAlbuquerqueNew MexicoUnited States

Free-space optical communication is a very promising alternative to fiber communication systems,in terms of ease of deployment and *** light has several features of utter relevance for free-space applications:low absorption when propagating in the atmosphere even under adverse conditions,robustness of the wavefront during long-distance propagation,and absence of regulations and restrictions for this range of wavelengths.A proof-of-concept of high-speed transmission taking advantage of intersubband devices has recently been demonstrated,but this effort was limited by the short-distance optical path(up to 1 m).In this work,we study the possibility of building a long-range link using unipolar quantum *** different detectors are used:an uncooled quantum cascade detector and a nitrogen-cooled quantum well-infrared *** evaluate the maximum data rate of our link in a back-to-back configuration before adding a Herriott cell to increase the length of the light path up to 31 *** using pulse shaping,pre-and post-processing,we reach a record bitrate of 30 Gbit s−1 for both two-level(OOK)and four-level(PAM-4)modulation schemes for a 31-m propagation link and a bit error rate compatible with error-correction codes.

关键词： free-space communication Stark-effect external modulator midinfrared photonics intersubband technology unipolar quantum devices

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酿造香槟的艺术气质——访泰亭哲香槟庄主pierre-Emmanuel Taittinger

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中外食品（酒尚） 2007年第7X期 102-105页

作者： angela 腾飞

在香槟的王国里,有一个品牌把艺术和酒完美地结合在了一起;在查尔斯王子和戴安娜王妃隆重的婚礼上,出现过它的身影;100%的霞多丽让人们品尝到它独特的清爽——它就是Taittinger香槟。一个夏日的花园酒会上,我见到了泰亭哲香槟庄主兼首... 详细信息

在香槟的王国里,有一个品牌把艺术和酒完美地结合在了一起;在查尔斯王子和戴安娜王妃隆重的婚礼上,出现过它的身影;100%的霞多丽让人们品尝到它独特的清爽——它就是Taittinger香槟。一个夏日的花园酒会上,我见到了泰亭哲香槟庄主兼首席酿酒师pierre-Emmanuel Taittinger先生,此次他专门来到中国,为我们带来他引以为傲的Taittinger香槟。

关键词： Emmanuel 酿酒师花园酒霞多丽艺术气质酒业公司中国葡萄酒波尔多 tinge 戴安娜

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