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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

minor fibrillar collagens,variable regions alternative splicing,intrinsic disorder,and tyrosine sulfation

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Protein & Cell 2012年第6期3卷 419-433页

作者： ming Fang Reed Jacob Owen mcDougal Julia thom Oxford Department of Biological sciences Boise State UniversityBoiseID 83725USA Department of Chemistry and Biochemistry Boise State UniversityBoiseID 83725USA Biomolecular Research Center Boise State UniversityBoiseID 83725USA

minor fibrillar collagen types V and XI,are those less abundant than the fibrillar collagen types I,II and *** alpha chains share a high degree of similarity with respect to protein sequence in all domains except the variable *** variation and,in some cases,extensive alternative splicing contribute to the unique sequence characteristics of the variable *** unique expression patterns in tissues exist,the functions and biological relevance of the variable regions have not been *** this review,we summarize the existing knowledge about expression patterns and biological functions of the collagen types V and XI alpha *** of biochemical similarities among the peptides encoded by each exon of the variable region suggests the potential for a shared *** alternative splicing,conservation of biochemical characteristics in light of low sequence conservation,and evidence for intrinsic disorder,suggest modulation of binding events between the surface of collagen fibrils and surrounding extracellular molecules as a shared function.

关键词： minor fibrillar collagens variable regions alternative splicing fibrillogenesis heparan sulfate binding sites intrinsic disorder tyrosine sulfation

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

Finite element analysis of overlay incorporating stress absorbing membrane interlayers against reflective cracking

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Journal of modern Transportation 2014年第2期22卷 104-111页

作者： O.m.Ogundipe N.H.thom A.C.Collop Civil Engineering Department Ekiti State University NTEC University of Nottingham Faculty of Technology De-Montfort University

A wheel tracking test was modelled to gain better understanding of the deflection and stress-strain distribution in an overlaid cracked pavements with and without membrane interlayer （sAmI）. For this purpose, commercial finite element software Abaqus 6.7-1 was used. Two different models were considered, one incorporating stress absorbing membrane interlayers （sAmIs） and the other without sAmI. In the study, full bond condition was assumed for the boundaries between the layers, and a linear elastic model was used for the analysis. The results show that introduction of sAmI caused greater deflection of the pavement. It is found that although with sAmIs, low stiffness is required, a very low stiffness may yield undesirable results. The results show that the introduction of sAmIs results in high strain concentration around the crack region, whilst the strain in the overlay is smaller than the values predicted in the models without sAmIs.

关键词： Overlay Interlayers Crack - strain stress

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

spatially resolved and multiplexed microRNA quantification from tissue using nanoliter well arrays

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microsystems & Nanoengineering 2020年第1期6卷 1007-1015页

作者： maxwell B.Nagarajan Augusto m.Tentori Wen Cai Zhang frank J.slack Patrick s.Doyle Department of Chemical Engineering Massachusetts Institute of TechnologyCambridgeMA 02139USA Hms Initiative for RNA medicine Department of PathologyHarvard Medical SchoolBeth Israel Deaconess Medical CenterBostonMA 02215USA

spatially resolved gene expression patterns are emerging as a key component of medical studies,including companion diagnostics,but technologies for quantification and multiplexing are *** present a method to perform spatially resolved and multiplexed microRNA(miRNA)measurements from formalin-fixed,paraffin-embedded(FFPE)*** nanoliter well arrays to pixelate the tissue section and photopatterned hydrogels to quantify miRNA,we identified differentially expressed miRNAs in tumors from a genetically engineered mouse model for non-small cell lung cancer(K-ras&(LsL-G12D/+);p53^(fl/fl)).This technology could be used to quantify heterogeneities in tissue samples and lead to informed,biomarker-based diagnostics.

关键词： resolved spatial lung

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

selenoprotein expression is regulated at multiple levels in prostate cells

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Cell Research 2006年第12期16卷 940-948页

作者： Cheryl m Rebsch frank J Penna Ⅲ Paul R Copeland Department of molecular Genetics Microbiology and immunology Department of molecular Genetics Microbiology and immunologyThe Cancer Institute of New JerseyUMDNJ-Robert Wood Johnson Medical School675 Hoes LanePiscatawayNJ 08854USA

selenium supplementation in a population with low basal blood selenium levels has been reported to decrease theincidence of several cancers including prostate *** on the clinical findings,it is likely that the antioxidantfunction of one or more selenoproteins is responsible for the chemopreventive effect,although low molecular weightseleno-compounds have also been posited to selectively induce apoptosis in transformed *** address the effects ofselenium supplementation on selenoprotein expression in prostate cells,we have undertaken an analysis of antioxidantselenoprotein expression as well as selenium toxicity in non-tumorigenic prostate epithelial cells(RWPE-1)and prostatecancer cells(LNCaP and PC-3).Our results show that two of the glutathione peroxidase family members(GPX1 andGPX4)are highly induced by supplemental selenium in prostate cancer cells but only slightly induced in RWPE-1 *** addition,GPX1 levels are dramatically lower in PC-3 cells as compared to RWPE-1 or LNCaP ***2 proteinand mRNA,however,are only detectable in RWPE-1 *** the three selenium compounds tested(sodium selenite,sodium selenate and selenomethionine),only sodium selenite shows toxicity in a physiological range of *** and in contrast to previous studies,RWPE-1 cells were significantly more sensitive to selenitethan either of the prostate cancer cell *** results demonstrate that selenoproteins and selenium metabolism areregulated at multiple levels in prostate cells.

关键词： prostate selenium selenoproteins glutathione peroxidase selenocysteine