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Geomorphic indices and relative tectonic uplift in the Guerrero sector of the Mexican forearc

Geoscience Frontiers 2017年第4期8卷 885-902页

作者： k.zysztof gaidzik.maría teresa ramírez-herrera Laboratorio Universitario de Geofísica Ambiental & Instituto de Geografía Universidad Nacional Autónoma de MéxicoCiudad Universitaria Berkeley Seismological Laboratory Department of Earth and Planetary ScienceUniversity of California Berkeley

Tectonically active areas,such as forearc regions,commonly show contrasting relief,differential tectonic uplift,variations in erosion rates,in river incision,and in channel gradient produced by ongoing tectonic ***,information on the tectonic activity of a defined area could be derived via landscape *** study uses topography and geomorphic indices to extract signals of ongoing tectonic deformation along the Mexican subduction forearc within the Guerrero *** this purpose,we use field data,topographical data,knickpoints,the ratio of volume to area（Rva）.the stream-length gradient index（St）,and the normalized channel steepness index（k_（sn））.The results of the applied landscape analysis reveal considerable variations in relief,topography and geomorphic indices values along the Guerrero sector of the Mexican subduction *** argue that the reported differences are indicative of tectonic deformation and of variations in relative tectonic uplift along the studied forearc.A significant drop from central and eastern parts of the study area towards the west in values of R_（VA）（from ~500 to^300）,St（from ~500 to ca.400）,maximum St（from ~1500-2500 to ~ 1000） and k_（sn）（from ~150 to ~100） denotes a decrease in relative tectonic uplift in the same *** suggest that applied geomorphic indices values and forearc topography are independent of climate and *** mechanisms responsible for the observed variations and inferred changes in relative forearc tectonic uplift call for further studies that explain the physical processes that control the forearc along strike uplift variations and that determine the rates of *** proposed methodology and results obtained through this study could prove useful to scientists who study the geomorphology of forearc regions and active subduction zones.

关键词： Relative tectonic uplift Forearc Active tectonics Geomorphic index Drainage network Mexican subduction zone

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kinetic study and kinetic parameters of lipase-catalyzed glycerolysis of sardine oil in a homogeneous medium

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Chinese Journal of Catalysis 2016年第4期37卷 596-606页

作者： Angela García Solaesa maría teresa Sanz Sagrario Beltrán Rodrigo Melgosa 布尔戈斯大学生物技术与食品科学系(化学工程部) 西班牙布尔戈斯09001

The production of polyunsaturated fatty acids （PUFAs） concentrates by enzymatic catalysis has gained interest due to their stereospecificity and the milder conditions employed compared to the use of inorganic catalysts. The enzymatic glycerolysis of sardine oil by Lipozymeò435 to get PUFA concentrates in the forms of di‐and monoacylglycerols （DAGs, MAGs） in an optimized amount of tert‐butanol as the organic solvent was studied. First, mass transfer limitation of the reaction sys‐tem was analyzed. The effects of different operating variables such as lipase loading, temperature and feed composition were investigated. A semi‐empirical kinetic model based on the reversible elementary reactions of glycerolysis and hydrolysis of the glycerides was employed to correlate the experimental kinetic data. A molar ratio glycerol：oil of 3：1 was the optimum, which produced more than 84 wt%of MAG at 323 k. A comparison with other glycerolysis systems was performed using MAG yield, reaction rate and significance of kinetic parameters.

关键词： Lipase Glycerolysis Tert-butanol Mass transfer kinetic model

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SIMULATED THERMAL ALTERATION OF STEROLS AND kETO-ALCOHOLS IN marINE SEDIMENTS OF THE OkINAWA TROUGH

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Chinese Journal of Oceanology and Limnology 1993年第4期11卷 343-350页

作者：姜善春 John k.Volkman teresa O'Leary 张惠之栾作峰 Guangzhou Branch of Institute of Geochemistry Academia Sinica Guangzhou 510640 CSIRO Division of Oceanography Hobart Tasmania Australia 7001 Institute of Oceanology Academia SinicaQingdao 266071

Compositional data on the sterol and alcohol fractions isolated from deep-sea marine sediments from the Okinawa Trough were obtained to determine the relative contribution from. marine and terrestrial inputs. Following extraction, the sterol plus alcohol fraction was isolated by layer chromatography, derivatized with BSTFA and then analysed by capillary GC and GC-MS. A suite of C26-C29 stenols and stanols and C30-C32 keto - alcohols were identified in the sediments. The thermal stability of the compounds in these sediments was studied by heating portions of the surface sediment in glass tubes fpr 16 hours at temperatures from 50℃ to 200℃.The C27 stanol/stenol ratio increased when temperatures went up to 175℃ , but the distribution of C30-C32 keto - alcohols remained unaffected. At 200℃ most of the sterols and keto - alcohols were destroyed.

关键词： sterols ketq -alcohols, thermal alteration, Okinawa Trough

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“Anti-Michael” and Michael Additions in the Reactions of 2-Arylmethyliden-1,3-Indandiones with 2-Aminothiophenol

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International Journal of Organic Chemistry 2017年第1期7卷 57-81页

作者： Jessica J. Sá nchez Garcí a Alberto D. Herná ndez-Suzan Elena martí nez-klimova marcos Flores-Alamo teresa ramí rez Apan Elena I. klimova Departamento de Quí mica Orgá nica Universidad Nacional Aut&oacute noma de Mé xico Facultad de Qu&iacute mica Cd. Universitaria Ciudad de M&eacute xico M&eacute xico Instituto de Quí mica Universidad Nacional Aut&oacute noma de Mé xico Facultad de Qu&iacute mica Cd. Universitaria Ciudad de M&eacute xico M&eacute xico

A novel 2-indano[2,3b]-2-ferrocenyl- and 2-indano[2,3b]-2-(p-methoxy-phenyl)[1,5]benzo-2,5-dihydrothiazepine 5a,b (addition Michael/cyclization) (~30.32%), indano[2,3b]-2-ferrocenyl- and 2-(p-methoxyphenyl)[1,4] benzothiazine 4a,b (addition “anti-Michael”/cyclization) (~45.43%), respectively, were obtained by the condensation of 2-ferrocenyl-and 2-(p-methoxy-phenyl)methyliden-1,3-indandiones 1a,b with o-aminothiophenol 2 in the presence of AcOH and HCl. A new “anti-Michael” addition reaction of 1,4-bis-heteronucleophile 2 into 2-arylmethyliden-1,3-indandiones was reported. As a result of this reaction the product 1a,b was obtained. The structures of the resultant compounds were elucidated by IR, 1H and 13C NMR spectroscopy, mass spectrometry, elemental and X-ray diffraction analysis. The in vitro antitumor activity of the obtained products was researched using the following human cancer cell lines: glioblastoma (CNS U-251), prostatic adenocarcinoma (PC-3), chronic myelogenous leukemia (k562), colorectal adenocarcinoma (HCT-15), mammary adenocarcinoma (MCF-7), and small cell lung cancer (SkLU) and the sulforhodamine B (SRB) method. Among these new compounds some thiazine and thiazepine derivatives showed compelling in vitro antitumor effects on cell lines k-562, HCT-15, SkLU-1 and MCF-7.

关键词： Ferrocene Addition “Anti-Michael” Reaction Cyclization 1 5-Thiazepines 4-Thiazines Antitumor Cell Lines

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Synthesis, Electrochemistry and Antitumor Activity of 1’H, 3’H(Me)-spiro-[(aza)benzimidazoline-2’, 3-(1,2-diferrocenylcyclopropenes)], 2-(1,2-Diferrocenylvinyl)benz- and Azabenzimidazoles

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Open Journal of Synthesis Theory and Applications 2014年第4期3卷 44-56页

作者： Jessica J. Sánchez García Luis Ortiz-Frade Elena martínez-klimova Juan C. García ramos marcos Flores-Alamo teresa ramírez Apan Elena I. klimova Faculty of Chemistry University National Autonomous of México México City México Centre of Investigation and Development Technology in Electrochemistry S.C. Queretaro México Departament of Bioengineering South Kensington Imperial College London London UK Institute of Chemistry University National Autonomous of México México City México

A new method of synthesis of 2-(1,2-diferrocenylvinyl)benz- and azabenzimidazoles (3a-f), (4a-f) and 1’H,3’H(Me)-spiro-[(aza)benzimidazoline-2’,3-(1,2-diferrocenylcyclopropenes)] (5a-f) via reactions of diferrocenyl(methylsulfanyl)cyclopropenylium iodide (1) with aromatic o-diamines (2a-f) in the presence of Et3N (80°C - 82°C) is described. The structures of the resultant compounds are established using IR, 1H and 13C NMR spectroscopy, mass spectrometry and elemental analysis. The structure of one compound, cis-2-(1,2-diferrocenylvinyl)-1-methylbenzimidazole (3b), is confirmed by X-ray diffraction analysis. The electrochemical properties of compounds 3a, 3b, 3d and 5f are investigated using cyclic square wave voltammetry. Two electrochemical processes (I-II), attributed to oxidation of the ferrocene moieties, and the values of E0’(I), E0’(II), DE0’(II-I) and comporportionation constant kcom are reported. The bioactivities of seven compounds 3a, 3c-f, 5d, 5f are evaluated. Compound 5f is the most active compound with a modest cytotoxic activity against six human cancer cell lines: U-251 (glioma), PC-3 (prostate cancer), k-562 (leukemia), HCT-15 (colon cancer), MCF-7 (breast cancer) and SkLU-1 (lung cancer).

关键词： Diferrocenyl(methylthio)cyclopropenylium 2-(1 2-Diferrocenylvinyl)(aza)benzimidazoles 1’H 3’H(Me)-spiro-[(aza)benzimidazoline-2’ 3-(1 2-diferrocenylcyclopropenes)] Electrochemistry Antitumor Activity

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Differential regulation of protein synthesis in skeletal muscle and liver of neonatal pigs by leucine through an mTORC1-dependent pathway

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Journal of Animal Science and Biotechnology 2012年第1期3卷 32-41页

作者： Agus Suryawan Hanh V Nguyen Rosemarie D Almonaci teresa A Davis Department of Pediatrics Baylor College of Medicine United States Department of Agriculture/Agriculture Research Service Children's Nutrition Research Center 1100 Bates Street Houston TX 77030 USA

Neonatal growth is characterized by a high protein synthesis rate that is largely due to an enhanced sensitivity to the postprandial rise in insulin and amino acids, especially leucine. The mechanism of leucine＇s action in vivo is not well understood. In this study, we investigated the effect of leucine infusion on protein synthesis in skeletal muscle and liver of neonatal pigs. To evaluate the mode of action of leucine, we used rapamycin, an inhibitor of mammalian target of rapamycin （mTOR） complex-1 （mTORC1）. Overnight-fasted 7-day-old piglets were treated with rapamycin for 1 hour and then infused with leucine （400 μmol·kg^-1·h^-1） for 1 hour. Leucine infusion increased the rate of protein synthesis, and ribosomal protein S6 kinase 1 （S6k1） and eukaryotic initiation factor （elF） 4E-binding protein-1 （4E-BP1） phosphorylation in gastrocnemius and masseter muscles （P 〈 0.05）, but not in the liver. The leucine-induced stimulation of protein synthesis and S6k1 and 4E-BP1 phosphorylation were completely blocked by rapamycin, suggesting that leucine action is by an mTORC1-dependent mechanism. Neither leucine nor rapamycin had any effect on the activation of the upstream mTQRC1 regulators, AMP-activated protein kinase and protein kinase B, in skeletal muscle or liver. The activation of elF2α and elongation factor 2 was not affected by leucine or rapamycin, indicating that these two pathways are not limiting steps of leucine-induced protein synthesis. These results suggest that leucine stimulates muscle protein synthesis in neonatal pigs by inducing the activation of mTORC1 and its downstream pathway leading to mRNA translation.

关键词： leucine mTORC1 neonatal pigs rapamycin skeletal muscle

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Ectopic expression of the osteogenic master gene RUNX2 in melanoma

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World Journal of Stem Cells 2018年第7期10卷 78-81页

作者： maria teresa Valenti Luca Dalle Carbonare Monica Mottes Department of Medicine University of Verona Department of Neurosciences Biomedicine and Movement Sciences University of Verona

The transcription factor RUNX2 is the osteogenic master gene expressed in mesenchymal stem cells during osteogenic commitment as well as in pre-osteoblasts and early ***,RUNX2 is also ectopically expressed in melanoma and other *** melanoma(MM)is a highly metastatic skin *** incidence of MM has increased considerably in the past *** expression levels and mutation rates of genes such as BRAF,kIT,NRAS,PTEN,P53,TERT and MITF are higher in melanoma than in other solid ***,transcription factors can affect cellular processes and induce cellular transformation since they control gene ***,several studies have identified alterations in RUNX2 *** particular,the regulation of kIT by RUNX2 and the increased expression of RUNX2 in melanoma specimens have been ***,whose transformation results in melanoma,arise from the neural crest and therefore show"stemness"***2 plays an important role in the re-activation of the MAPk and PI-3k/AkT pathways,thus endowing melanoma cells with a high metastatic *** melanoma,the most frequent metastatic sites are the lung,liver,brain and lymph *** addition,bone metastatic melanoma has been ***,studies focusing on RUNX2may contribute to the identification of an appropriate oncotarget in melanoma.

关键词： RUNX2 Mesenchymal stem cells Epitelial mesenchymal transition Bone Melanoma

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Chemistry and particle size distribution of respirable coal dust in underground mines in Central Eastern Europe

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International Journal of Coal Science & Technology 2022年第1期9卷 200-216页

作者： Pedro Trechera Xavier Querol Robert Lah Diane Johnson Aleksander Wrana Ben Williamson teresa Moreno Instituto de Diagnostico Ambiental Y Estudios del Agua Consejo Superior de Investigaciones Cientificas(IDAEACSIC)C/Jordi Girona 18‑2608034 BarcelonaSpain Department of Natural Resources and Environment Industrial and TIC Engineering(EMIT-UPC)08242 ManresaSpain Premogovnik Velenje d.d Partizanskacesta 783320 VelenjeSlovenia Camborne School of Mines University of ExeterPenrynCornwall TR109FEUK Department of Extraction Technology and Mining Support Central Mining Institute(GIG)40‑166 KatowicePlacGwarkow 1Poland

Despite international efforts to limit worker exposure to coal dust,it continues to impact the health of thousands of miners across *** coal dust has been studied to improve risk models and its control to protect *** size distribution analyses shows that using spraying systems to suppress airborne dusts can reduce particulate matter concentrations and that coals with higher ash yields produce finer *** are marked chemical differences between parent coals and relatively coarse deposited dusts(up to _(500)μm,DD_(500)).Enrichments in Ca,k,Ba,Se,Pb,Cr,Mo,Ni and especially As,Sn,Cu,Zn and Sb in the finest respirable dust fractions could originate from:(i)mechanical machinery wear;(ii)variations in coal mineralogy;(iii)coal fly ash used in shotcrete,and carbonates used to reduce the risk of *** enrichments in Ca in mine dusts are attributed to the use of such concrete,and elevated k to raised levels of phyllosilicate mineral *** concentrations are higher in the parent coal than in the DD_(500),probably due to relatively lower levels of organic *** concentrations of all elements observed in this study remained below occupational exposure limits.

关键词： Coal dust Deposited dust Respirable dust Particle size distribution Dust chemistry PM10 coal dust exposure

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Systematic review: Renin-angiotensin system inhibitors in chemoprevention of hepatocellular carcinoma

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World Journal of Gastroenterology 2019年第20期25卷 2524-2538页

作者： Michele Barone maria teresa Viggiani Giuseppe Losurdo mariabeatrice Principi Alfredo Di Leo Gastroenterology Section Department of Emergency and Organ Transplantation University of Bari Aldo Moro

BACkGROUND Neoangiogenesis is one of the key pathogenetic mechanisms in hepatocellular carcinoma (HCC). Modulation of the renin-angiotensin system (RAS) by angiotensin-converting enzyme inhibitors (ACE-Is) and angiotensin receptor blockers (ARBs) seems to be a possible adjuvant therapy for HCC, due to the antiangiogenic and anti-fibrogenic activity of these drugs. AIM To elucidate the role of ARBs and ACE-Is in HCC. METHODS We performed an electronic search of the literature using the most accessed online databases (PubMed, Cochrane library, Scopus and Web of Science), entering the query terms "angiotensin-converting enzyme inhibitors" OR "ACE inhibitors" OR "ACE-I" AND "hepatocarcinoma*" OR "hepatocellular carcinoma;moreover "angiotensin II type 1 receptor blockers" OR "ARBs" AND "hepatocarcinoma*" OR "hepatocellular carcinoma". Eligibility criteria were:(1) prospective or retrospective clinical studies;(2) epidemiological studies;and (3) experimental studies conducted in vivo or in vitro. Abstracts, conference papers, and reviews were excluded a priori. We limited our literature search to articles published in English, in peer-reviewed *** Thirty-one studies were selected. Three interventional studies showed that ACEIs had a significant protective effect on HCC recurrence only when used in combination with vitamin k or branched chain aminoacids, without a significant increase in overall survival. Of six retrospective observational studies, mainly focused on overall survival, only one demonstrated a prolonged survival in the ACE-Is group, whereas the two that also evaluated tumor recurrence showed conflicting results. All experimental studies displayed beneficial effects of RAS inhibitors on hepatocarcinogenesis. Numerous experimental studies, conducted either on animals and cell cultures, demonstrated the anti-angiogenetic and antifibrotic effect of ACE-Is and ARBs, thanks to the suppression of some cytokines such as vascular endothelial growth factor

关键词： Cirrhosis Renin Angiotensin Survival Cancer prevention Hepatocarcinoma

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Exploration on Blended Teaching Mode of Adult Occupational English

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海外英语 2020年第23期 281-282页

作者：吴雪花蔡雪英 teresa k.Debeacker 江苏海事职业技术学院美国俄克拉何马大学教育学院

This study explored occupational English blended teaching mode for adult learners,and introduced the six steps and characteristics in a vocational institute.

关键词： blended teaching mode adult occupational English

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