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Ethnography and the Internet： Taking Account of Emerging Technological Landscapes

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Fudan Journal of the Humanities and Social Sciences 2017年第3期10卷 315-329页

作者： christine Hine Department of Sociology University of Surrey Guildford Surrey GU2 7XH UK

This article explores the strengths of ethnography as a methodology for exploring the complex social landscape of the contemporary Intemet. The article outlines the historical development of the Intemet, from Web 1.0 to a participatory Web 2.0 embedded within everyday life and ultimately to the prospect of an autonomous Internet of Things. The benefits of an ethnographic approach for understanding such developments in depth and examining taken-for-granted assumptions are outlined alongside an account of some of the challenges that digital technologies pose for an ethnographic methodology. Amongst these challenges are the difficulties inherent in mapping out a field site that effectively captures the complexity of online/offline connections and of developing a sufficient degree of immersion and co-presence for a rich understanding to be attained. Finally, the challenges offered by the emergence of mobile Internet, algorithmic filtering of information and unpredictable flows of data are explored. It is suggested that the ethnographer of the Internet can usefully position their task as being to explore a socially constructed yet technologically mediated landscape, immersing themselves in it, interrogating how others experience it and mapping the ways in which it becomes meaningful to those who navigate its complexities.

关键词： Internet Ethnography Social media Participant observation methodology Community Internet of Things Field site Landscape Algorithm

Increased Benthic Algal Primary Production in Response to the Invasive Zebra mussel (Dreissena polymorpha) in a Productive Ecosystem,Oneida Lake,New York

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Journal of Integrative Plant Biology 2008年第11期50卷 1452-1466页

作者： Rebecca K.Cecala christine m.mayer Kimberly L.Schulz Edward L.mills Biology Department Syracuse University Biology Deptartment Department of Environmental Sciences and Lake Erie Center University of Toledo State University of New York School of Environmental Science and Forestry Cornell Biological Field Station and Department of Natural Resources Cornell University

Increased water clarity associated with zebra mussel （Dreissena polymorpha） populations may favor benthic algal primary production in freshwater systems previously dominated by pelagic phytoplankton production. While zebra mussel-mediated water clarity effects on benthic primary production have been implicated in published reports, few production estimates are available. This study estimates benthic primary production in Oneida Lake, NY before and after zebra mussel invasion （1992）, using measured photosynthetic parameters （P^Bmax, α^β and β） from sampled benthic algal communities. In the summers of 2003 and 2004, primary production was measured as O2 evolution from algal communities on hard （cobble） and soft （sediment） substrate from several depths. We also backcast estimates of benthic primary production from measurements of light penetration since 1975. Estimates of whole-lake epipelic and epilithic algal primary production showed a significant （4%） increase and exhibited significantly less interannual variability subsequent to the establishment of zebra mussels. We applied our model to two lakes of differing trophic status; the model significantly overestimated benthic primary production in a hypereutrophic lake, but there was no significant difference between the actual and predicted primary production values in the oligotrophic lake. The hypereutrophic lake had higher zebra mussel densities than Oneida （224 vs. 41 per sample respectively）. Though total community respiration （measured in total darkness） was factored into our model predictions of production, our model may need modification when heterotrophic respiration is a large portion of total community metabolism.

关键词： Dreissena ecosystem engineering nonindigenous species Oneida Lake periphyton primary production.

Unexpected Stereospecific Rearrangement-Addition Reaction of Trisubstituted Gibberellin Epoxides with Trimethylaluminium

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Chinese Chemical Letters 2001年第10期12卷 855-858页

作者： An Qi CHEN christine L.WILLIS Department of Chemistry Xiamen UniversityXiamen 361005 School of Chemistry University of BristolBristolUK BS8 1TS

A novel rearrangement-addition reaction of trisubstituted gibberellin epoxides with trimethylaluminium is reported. The reaction proceeds stereospecifically to give tertiary methyl alcohols. The possible mechanism for... 详细信息

关键词： gibberellin epoxide trimethylaluminium rearrangement-addition reaction

Cloud Aesthetics:An Epistemological Challenge, Aesthetics from Below, and the Question of History

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Journal of Foreign Languages and Cultures 2021年第1期5卷 15-25,155页

作者： christine Blaettler Kiel University

Clouds are often appealed to when an objection is raised to the rationalist knowledge paradigm of the clear and distinct,as formulated by Rene *** such cases,clouds serve to establish an anti-classically oriented,non-hierarchical and non-determinative,chaos-theoretically informed *** informed by this tendency,this essay proposes to examine clouds as an epistemological challenge,capable of exposing specific tensions in science,philosophy,and art *** fields negotiate questions of perception and representation,hence aesthetic problems,on the basis of which this contribution formulates an“aesthetics from below.”Such an aesthetics does not proceed from aesthetic theories,nor is it based on fuzzy concepts;rather,it begins with reflection on perception-based experience and specifically historical artifacts and seeks to lead these toward the work of *** this essay,this is accomplished through an examination of the significance of clouds in Siegfried Kracauer’s philosophical reflections on history.

关键词： clouds aesthetics epistemology history Kracauer

The Rain on Underground Porous media Part Ⅰ:Analysis of a Richards model

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Chinese Annals of mathematics,Series B 2013年第2期34卷 193-212页

作者： christine BERNARDI Adel BLOUZA Linda EL ALAOUI Laboratoire Jacques-Louis Lions CNRS & Université Pierre et Marie CurieBC 1874 Place Jussieu75252 Paris Cedex 05France Laboratoire de mathématiques Raphaёl Salem(UmR 6085 CNRS) Université de RouenAvenue de l'UniversitéBP 1276801 Saint-tienne-du-RouvrayFrance Universit Paris 13 Sorbonne Paris CitLAGACNRS(UMR 7539)F-93430VilletaneuseFrance

The Richards equation models the water flow in a partially saturated underground porous medium under the *** it rains on the surface,boundary conditions of Signorini type must be considered on this part of the *** authors first study this problem which results into a variational inequality and then propose a discretization by an implicit Euler's scheme in time and finite elements in *** convergence of this discretization leads to the well-posedness of the problem.

关键词： Richards equation, Porous media, Euler's implicit scheme, Finite element discretization Parabolic variational inequality

Caffeic acid phenethyl ester modifies the Thl/Th2 balance in ileal mucosa afterγ-irradiation in the rat by modulating the cytokine pattern

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World Journal of Gastroenterology 2006年第31期12卷 4996-5004页

作者： Olivier Grémy marc Benderitter christine Linard Institute for Radioprotection and Nuclear SafetyIRSN BP n°17F-92262 Fontenay-aux-Roses CedexFrance

AIm： To pharmacologically modulate Th polarization in the ileum exposed to ionizing radiation by using the immuno-modulatory/apoptotic properties of Caffeic Acid Phenethyl Ester （CAPE）. mETHODS： Rats received CAPE （30 mg/kg） treatment ip 15 min prior to intestinal 10 Gy γ-irradiation and once a day for a 6 d period alter irradiation. Expression of genes implicated in Th differentiation in ileal mucosa （IL-23/IL-12Rβ2）, Th cytokine responses （IFN-γ, IL-2, IL-4, IL-13）, Th migratory behaviour （CXCR3, CCR5, CCR4）, Th signalling suppressors （SOCS1, SOCS3）, transcription factor （T-Bet, GATA-3） and apoptosis （FasL/Fas, TNF/TNFR, XIAP, Bax, caspase-3） was analyzed by RT-PCR 6 h and 7 d post-irradiation. CD4^＋ and TUNEL positive cells were visualized by immunostaining. RESULTS： The expression of Thl-related cytokine/ chemokine receptors （IFN-γ, IL-2, CXCR3, CCR5） was repressed at 7 d post-irradiation while Th2 cell cytokine/ chemokines （IL-4, IL-13, CCR4） were not repressed or even upregulated. The irradiation-induced Th2 profile was confirmed by the upregulation of both Th2-specific transcription factor GATA-3 and SOCS3. Although an apoptosis event occurred 6 h alter 10 Gy of intestinal γ-irradiation, apoptotic mediator analysis showed a tendency to apoptotic resistance 7 d post-irradiation. CAPE amplified apoptotic events at 6h and normalized Bax/FasL expressions at 7 d. CONCLUSION： CAPE prevented the ileal Th2 immune response by modulating the irradiation-influenced cytokine environment and apoptosis.

关键词： Intestinal inflammation T cells Irradiation Apoptosis

Stereoselective Functionalization at C-2 and C-3 of the Gibberellin via an Intramolecular Free Radical Cyclization Approach

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Chinese Chemical Letters 2001年第5期12卷 397-398页

作者： An Qi CHEN christine L.WILLIS Department of Chemistry Xiamen UniversityXiamen3610052School of ChemistryUniversity of BristolBristolUK BS81TS

Stereoselective functionalization at C-2 and C-3 of the gibberellin skeleton was achieved via an intramolecular free radical cyclization approach using a tethered C-19 halomethyl ester as the radical precursor.

关键词： Gibberellin lactonization free radical cyclization.

Acute and persisting Th2-like immune response after fractionated colorectal γ-irradiation

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World Journal of Gastroenterology 2008年第46期14卷 7075-7085页

作者： Olivier Grémy marc Benderitter christine Linard Institute for Radioprotection and Nuclear safety

AIm： To investigate if an immune imbalance may account for the development and progression of chronic radiation enteritis. We analyzed the Th1/Th2 immune response profile early and 6 mo after fractionated colorectal irradiation. mETHODS： A rat model of fractionated colorectal γ-irradiation （4-Gy fractions, 3 fractions per week） was designed to investigate the effects of cumulative dose on inflammatory mediators （cytokines and chemo- kines） and immune response （Th1/Th2 profile and immunosuppressive mediator IL-10） during acute （early） response and 6 mo after the end of fractionated irradiation （chronic response）. Analyses were performed 1 d after the cumulative doses of 16 Gy and 36 Gy and 1 d, 3 d, and 26 wk after the cumulative dose of 52 Gy. RESULTS： Without causing histological damage, fractionated radiation induced elevated expression of IL-1β, TNFα, mCP-1, and iNOS in distal colonic mucosa during the early post-irradiation phase. At that time, a Th2 profile was confirmed by expression of both the Th2- specific transcription factor GATA-3 and the chemokine receptor CCR4 and by suppression of the Thl cytokine IFNγ/IP-10 throughout the irradiation protocol. After 6 mo, despite the 2-fold reduction of iNOS and mCP-1 levels, the Th2 profile persisted, as shown by a 50% reduction in the expression of the Thl transcription factor T-bet, the chemokine receptor CCXCR3, and the IFNγ/ STAT1 pathway. At the same time-point, the immunosuppressive IL-10/STAT3 pathway, known to regulate the Th1/Th2 balance, was expressed, in irradiated rats, at approximately half its level as compared to *** suppression was associated with an overexpression of SOCS3, which inhibits the feedback of the Thl polarization and regulates IL-10 production. CONCLUSION： Colorectal irradiation induces Th2 polarization, defective IL-10/STAT3 pathway activation and SOCS3 overexpression. These changes, in turn, maintain a immunological imbalance that persists in the long term.

关键词： Colorectum Inflammation Th2 cells Irradiation, Suppressor of cytokine signaling 3 STAT

Sympathetically evoked Ca2+signaling in arterial smooth muscle

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Acta Pharmacologica Sinica 2006年第12期27卷 1515-1525页

作者： Joseph ZACHARIA christine LAmONT Withrow Gil WIER Department of Physiology University of Maryland School of MedicineBaltimoreMaryland 21201USA Department of Pharmacology Key Laboratory of Environment and Genes Related to Diseases of Ministry of EducationSchool of MedicineXi-an Jiaotong UniversityXi-an 710061China Department of Physiology University of Maryland School of MedicineBaltimoreMerryland 21201USA

The sympathetic nervous system plays an essential role in the control of totalperipheral vascular resistance and blood flow,by controlling the contraction ofsmall *** sympathetic nerves release ATE norepinephrine（NE）and neuropeptide *** review summarizes our knowledge of the intracellularCa2+signals that are activated by ATP and NE,acting respectively on P2X1and α1-adrenoceptors in arterial smooth *** neurotransmitter produces a uniquetype of post-synaptic Ca2+signal and associated *** neural releaseof ATP and NE is thought to vary markedly with the pattern of nerve activity,probably reflecting both pre-and post-synaptic ***,we showthat Ca2+signaling during neurogenic contractions activated by trains of sympa-thetic nerve fiber action potentials are in fact significantly different from thatelicited by simple bath application of exogenous neurotransmitters to isolatedarteries（a common experimental technique）,and end by identifying importantquestions remaining in our understanding of sympathetic neurotransmission andthe physiological regulation of contraction of small arteries.

关键词： sympathetic nerve Ca2+ signaling arterial smooth muscles receptors junctional Ca2+ transients confocal microscope