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TeV astronomy

Frontiers of physics 2013年第6期8卷 714-747页

作者： frank m. Rieger max-Planck-Institut fiir Kernphysik P.O. Box 103980 69029 Heidelberg Germany Institut de Ciencies de L'Espai (IEEC-CSIC) Campus UAB Torte C5 08193 Bellaterra Spain Dublin Institute for Advanced Studies 31 Fitzwilliam Place Dublin 2 Ireland European Associated Laboratory for Gamma-Ray Astronomy jointly supported by CNRS and MPG

With the successful realization of the current-generation of ground-based detectors, TeV Astronomy has entered into a new era. We review recent advances in VHE astronomy, focusing on the potential of Imaging Atmospheric Cherenkov Telescopes （IACTs）, and highlight astrophysical implications of the results obtained within recent years.

关键词： TeV astronomy gamma-rays Cherenkov telescopes high-energy astrophysics

Influence of groundwater depth on species composition and community structure in the transition zone of Cele oasis

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Journal of Arid Land 2010年第4期2卷 235-242页

作者： frank m. THOmAS Department of Geobotany University of Trier Behringstraβe 21 54296 Trier Germany

The paper analyzes the hypothesis that the distribution of dominant plant species and characteristics of plant communities are related to groundwater depth. The results showed that variations of groundwater depth impacted distributions and characteristics of dominant plant communities. However, besides groundwater depth, the community composition and species diversity were also influenced by physiognomy of the habitat. Based on the similarity coefficient, the differences between dominant plant communities were significant at different groundwater depths. Compared with other results relating to desert vegetation and groundwater depth, variations of community distribution were similar at the large spatial scale. However, in this extremely arid region, there were significant differences in community type and community succession when compared with other arid regions, especially in relationship to deep groundwater depth. With groundwater depth from deep to shallow, communities transformed with the sequence of Alhagi communities, Tamarix spp. communities, Populus communities, Phragmites communities, and Sophora communities. At groundwater depth of less than 6.0 m, the community type and composition changed, and the species diversity increased. Among these dominant species, Tamarix exhibited the biggest efficiency in resource utilization according to niche breadth, which means it possessed the best adaptability to environmental conditions at the oasis margins.

关键词： groundwater depth community characteristic niche breadth oases Taklamakan desert

HIV protease:late action to prevent immune detection

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Signal Transduction and Targeted Therapy 2021年第5期6卷 1408-1409页

作者： Konstantin m.J.Sparrer frank Kirchhoff Institute of molecular Virology Ulm University Medical CenterUlmGermany

A recent study published in Science by Wang and colleagues shows that premature activation of the HIV-1 protease leads to caspase activation and recruitment domain 8(CARD8)inflammasome-mediated pyroptosis of infected macrophages and CD4+T cells(Fig.1).These findings might help to improve approaches aiming to eliminate the latent viral reservoirs upon HIV-1 *** invading viral pathogens trigger the innate immune system and are usually rapidly controlled and eventually *** sense viral intruders via so-called pattern recognition receptors(PRRs)capable of detecting pathogen-associated molecular patterns(PAmPs)allowing discrimination between self and *** many cases,these patterns are viral nucleic acids that show pathogen-specific structures or emerge at the wrong localization in the ***,activation of PRRs by their respective ligands leads to the induction of various anti-viral signaling cascades,among them the inflammasome.

关键词： eventually action eliminate

Endoscopic papillectomy: Data of a prospective observational study

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World Journal of Gastroenterology 2013年第27期19卷 4316-4324页

作者： Uwe Will Anne-Kathrin müller frank Fueldner Igor Wanzar frank meyer Department of Gastroenterology Municipal Hospital Department of Surgery University Hospital

AIm:To investigate the clinical value of endoscopic papillectomy indicated by feasibility and safety of the procedure in various diseases of the papilla in a representative number of patients in a setting of daily clinical and endoscopic practice and care by means of a systematic prospective observational study. mETHODS:Through a defined time period, all consecutive patients with tumor-like lesions of the papilla, who were considered for papillectomy, were enrolled in this systematic bicenter prospective observational study, and subdivided into 4 groups according to endoscopic and endoscopic ultrasonography (EUS) findings as well as histopathological diagnosis:adenoma; carcinoma/ neuroendocrine tumor (NET)/lymphoma; papilla into which catheter can not be introduced; adenomyomatosis, respectively. Treatment results and outcome were characterized by R0 resection, complication, recurrence rates and tumor-free ***:Over a 7-year period, 58 patients underwent endoscopic papillectomy. main symptoms prompting to diagnostic measures were unclear abdominal pain in 50% and cholestasis with and without pain in 44%. Overall, 54/58 patients [inclusion rate, 93.1%; sex ratio, males/females = 25/29 (1:1.16); mean age, 65 (range, 22-88) years] were enrolled in the study. Prior to papillectomy, EUS was performed in 79.6% (n = 43/54). Group 1 (adenoma, n = 24/54; 44.4%):91.6% (n = 22/24) with R0 resection; tumor-free survival after a mean of 18.5 mo, 86.4% (n = 19/22); recurrence, 13.6% (n = 3/22); minor complications, 12.5% (n = 3/24). Group 2 (carcinoma/NET/lymphoma, n = 18/54; 33.3%):75.0% (n = 10/18) with R0 resection; tumor-free survival after a mean of 18.5 (range, 1-84) mo, 88.9% (n = 8/9); recurrence, 11.1% (n = 1/9). Group 3 (adenomyomatosis, n = 4/54; 7.4%). Group 4 (primarily no introducible catheter into the papilla, n = 8; 14.8%). The overall complication rate was 18.5% (n = 10/54; 1 subject with 2 complications):Bleeding, n = 3; pancreatitis, n = 7; perforat

关键词： Papilla of Vater Papillectomy Endoscopic ultrasonography Adenoma Carcinoma Carcinoid-like tumor Adenomyomatosis

Selective Suspension in Aqueous Sodium Dodecyl Sulfate According to Electronic Structure Type Allows Simple Separation of metallic from Semiconducting Single-Walled Carbon Nanotubes

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Nano Research 2009年第8期2卷 599-606页

作者： Kai moshammer frank Hennrich manfred m.Kappes Forschungszentrum Karlsruhe Institut für NanotechnologieD-76021 KarlsruheGermany Institut für Physikalische Chemie Universität KarlsruheD-76128 KarlsruheGermany

Both density gradient centrifugation and gel electrophoresis have been reported to allow high throughput separation of metallic from semiconducting single-walled carbon nanotubes(SWNTs)when using aqueous sodium dodecyl sulphate(SDS)*** show here that both methods rely on an initial dispersion-by-sonication step,which is already selective with respect to electronic structure *** corresponding aqueous SDS“starting”suspensions obtained after sonication and purifi cation by simple centrifugation(70,000 g,1 h)contain semiconducting SWNTs primarily in the form of small bundles whereas metallic SWNTs are predominantly suspended as individual *** gradient centrifugation then separates the bundles from the individual tubes on the basis of differences in their overall buoyant *** electrophoresis separates the longer bundles from the shorter individual tubes on the basis of their different *** also demonstrate that such starting suspensions can be fractionated according to electronic structure type by even simpler techniques such as size exclusion chromatography or gel fi ltration,thus opening the way for simple scale-up.

关键词： Single-walled carbon nanotubes metallic–semiconducting separation electrophoresis density gradient centrifugation size exclusion chromatography

Cap snatch prevention:a novel approach to tackle influenza viruses

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2435-2436页

作者： Konstantin m.J.Sparrer frank Kirchhoff Institute of molecular Virology Ulm University Medical CenterUlmGermany

A recent study published in Science1 by Tsukamoto and colleagues shows that a derivative of tubercidin,a natural product from Streptomyces,selectively inhibits influenza A and B viruses(IAV and IBV,respectively).The compound targets the host RNA methyltransferase mTr1,and thus prevents viral“cap snatching”(Fig.1).These results may help to develop novel drugs that target viral host dependency factors and are thus less likely to induce viral resistance.

关键词： prevention influenza likely

Using occupancy models to determine mammalian responses to landscape changes

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Integrative Zoology 2009年第2期4卷 232-239页

作者： Jeremy m.NICHOLSON frank T.VAN mANEN Department of Forestry Wildlifeand FisheriesUniversity of TennesseeKnoxvilleTennesseeUSA US Geological Survey Southern Appalachian Research BranchUniversity of TennesseeKnoxvilleTennesseeUSA

Determining impacts of anthropogenic landscape changes on wildlife populations is *** the challengesDetermining impacts of anthropogenic landscape changes on wildlife populations is *** the challenges of designing field studies to document conditions before and after landscape changes occur,assessment of popula-of designing field studies to document conditions before and after landscape changes occur,assessment of popula-tion responses(*** in population density)often provide poor inference because of sampling *** responses(*** in population density)often provide poor inference because of sampling *** of occupancy,however,only requires data on detection or non-detection of a species and might provideEstimation of occupancy,however,only requires data on detection or non-detection of a species and might provide better *** demonstrate the utility of occupancy models,we used data from an American black bear(Ursusbetter *** demonstrate the utility of occupancy models,we used data from an American black bear(Ursus americanus Pallas)population in North Carolina,USA to test our research hypothesis that documented declines inamericanus Pallas)population in North Carolina,USA to test our research hypothesis that documented declines in site occupancy of black bears would be greater near a new four-lane *** used multi-season occupancysite occupancy of black bears would be greater near a new four-lane *** used multi-season occupancy models to estimate site occupancy based on bear visitation to survey sites before and after completion of the newmodels to estimate site occupancy based on bear visitation to survey sites before and after completion of the new highway and as a function of distance to the *** occupancy declined from 0.81 to 0.35 between the twohighway and as a function of distance to the *** occupancy declined from 0.81 to 0.35 between the two s

关键词： landscape changes mammalian responses occupancy models transportation infrastructure Ursus americanus.

Growth of the tropical Pinus kesiya as influenced by climate and nutrient availability along an elevational gradient

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Journal of Plant Ecology 2020年第1期13卷 97-106页

作者： Le Tuan Ho Raimund Schneider frank m.Thomas Department of Geobotany University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany Department of Forest Resources management Faculty of ForestryNong Lam University HCMCThu Duc DistrictHo Chi Minh CityVietnam Department of Soil Science University of TrierFaculty of Regional and Environmental SciencesBehringstraße 2154296 TrierGermany

Aims In contrast to temperate regions,the reasons for growth reductions of individual tree species along elevational gradients in tropical mountain ranges are poorly known,especially for tropical *** aimed at testing whether climatic or edaphic conditions are responsible for the reduced growth of Pinus kesiya,a widely distributed pine species of southern and south-eastern Asia,at higher *** We analysed the stem diameter increment and the isotope discrimination against ^(13)C(△^(13)C)in tree rings of *** along an elevational gradient of~900 to~2000 m *** the mountain ranges of South-Central Vietnam,and related growth to△^(13)C and to climatic and edaphic *** findings We found no consistent correlation patterns between the basal area increment(BAI)of the trees and temperature or *** contrast,across the elevational gradient,we obtained significantly negative correlations of BAI with△^(13)C and with the C/N ratios and theδ^(15)N signature of the upper mineral *** was positively correlated with the concentrations of plant-available phosphorus(P_(a))and of“base”cations(calcium,magnesium,potassium)in the *** conclude that lower temperatures at higher elevations exert an indirect effect on tree growth by inducing higher C/N ratios and by reducing the rate of nitrogen(N)and P mineralization,which may be further hampered by lower concentrations of“base”cations(upon enhanced leaching by precipitation)and a negative feedback from low availability of mineralized N and P at higher *** results may be transferable to the uppermost growth limit of *** and to other montane regions of the species’occurrence.

关键词： dendroecology pine pointer year soil nutrient stable isotope

Asymptotics and Blow-up for mass Critical Nonlinear Dispersive Equations(Dedicated to Professor Ham Brezis on the occasion of his 70th birthday)

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Chinese Annals of mathematics,Series B 2017年第2期38卷 579-590页

作者： frank mERLE Universitéde Cergy-pontoise MathématiquesCNRSCNRSF-95000 Cergy-PontoiseFrance Institut des HautesEtudes Scientifiques 35 Route de Chartres91440 Bures-sur-YvetteFrance

The author considers mass critical nonlinear Schrdinger and Korteweg-de Vries equations. A review on results related to the blow-up of solution of these equations is given.

关键词： Dispersive nonlinear PDE, Criticality, Asymptotics, Blow-up, Globalsolution, Soliton