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Effect of Using Two Different Types of Carbon Nanotubes for Blackberry (Rubus adenotrichos) in Vitro Plant Rooting, Growth and Histology

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American Journal of Plant Sciences 2014年第24期5卷 3510-3518页

作者： Dora Flores Randall Chacón Luis alvarado Alexander Schmidt carlos alvarado Juan Chaves Centro de Investigación en Biotecnología Instituto Tecnológico de Costa Rica Cartago Costa Rica Laboratorio de Nanotecnología Instituto Tecnológico de Costa Rica Cartago Costa Rica

Nanoparticles are able to interact with biomolecules, creating functional nanosystems for transportation within in vivo cells, and leading to the study of their potential applications in the field of plant biotechnology. Therefore, the aim of this research was to determine the growth and rooting effect of functionalized (SWCNTs-COOH) and non-functionalized nanoparticles with iron residue inner particles (SWCNTs-Fe) in blackberry (Rubus adenotrichos) in vitro plants. Two types of SWCNTs were used, both of them characterized in a solid sample through Raman spectroscopy (λ = 532 nm) showing differences in the G band between SWCNT + Fe and SWCNT + COOH. The in vitro plants (approximately 15 mm length) were inoculated in a rooting medium. Six treatments were established: 4, 8, 12 μg/ml for each type of SWCNTs and a control without nanotubes. The assessed variables consisted of the average number of days for root emergence, average number of roots per plant, average root length per plant and the average stem length. This study determined that, in general, the SWCNTs-COOH promoted the growth of the in vitro plants under this assay, when compared to the SWCNTs-Fe trials. The lowest SWCNTs-COOH dose evidenced the best results for the assessed variables. Additionally, the histological analysis also evidenced that the plants treated with SWCNTs-COOH nanotubes (4 μg/ml) increased their cellular metabolism when compared to the control group.

关键词： Single Walled Carbon Nanotubes Growth Rooting Blackberry TEM

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Mode-and wavelength-multiplexed transmission with crosstalk mitigation using a single amplified spontaneous emission source

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Photonics Research 2019年第11期7卷 1363-1369页

作者： Yetian Huang Haoshuo Chen Hanzi Huang Zhengxuan Li Nicolas K.Fontaine Roland Ryf Juan carlos alvarado Rodrigo Amezcua-Correa John van Weerdenburg Chigo Okonkwo A.M.J.Koonen Yingxiong Song Min Wang Key Laboratory of Specialty Fiber Optics and Optical Access Networks Joint International Research Laboratory of Specialty Fiber Optics and Advanced CommunicationShanghai Institute for Advanced Communication and Data ScienceShanghai UniversityShanghai 200444China Nokia Bell Labs HolmdelNew Jersey 07733USA CREOL University of Central FloridaOrlandoFlorida 32816USA Institute for Photonic Integration Eindhoven University of Technology5600 MBEindhovenThe Netherlands

We propose to use the low-coherence property of amplified spontaneous emission(ASE) noise to mitigate optical crosstalk, such as spatial, polarization, and modal crosstalk, which currently limits the density of photonic integration and fibers for dense space-division multiplexing. High optical crosstalk tolerance can be achieved by ASE-based low-coherence matched detection, which avoids dedicated optical lasers and uses spectrally filtered ASE noise as the signal carrier and as a matched local oscillator. We experimentally demonstrate spatial and modal crosstalk reduction in multimode fiber(MMF) and realize mode-and wavelength-multiplexed transmission over1.5-km MMF supporting three spatial modes using a single ASE source. Performance degradation due to model dispersion over MMF is experimentally investigated.

关键词： crosstalk polarization matched

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Numerical Simulation of the Blood Flow through a Brain Vascular Aneurysm with an Artificial Stent Using the SPH Method

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Engineering（科研） 2018年第12期10卷 891-912页

作者： Leonardo Di G. Sigalotti Jaime Klapp Karla Pedroza Edgar Nathal carlos E. alvarado-Rodríguez Area of Physics of Irreversible Processes Department of Basic Sciences Autonomous Metropolitan University-Azcapotzalco (UAM-A) Mexico City Mexico Physics Department National Institute of Nuclear Research (ININ) Ocoyoacac Mexico Los Cabos H+ Hospital San José del Cabo Mexico National Institute of Neurology and Neurosurgery “Manuel Velasco Suárez” Mexico City Mexico Departament of Chemical Engineering DCNyE University of Guanajuato Guanajuato Mexico

We present numerical simulations of blood flow through a brain vascular aneurysm with an artificial stent using Smoothed Particle Hydrodynamics (SPH). The aim of this work is to analyze how the flow into an aneurysm changes using different stent configurations. The initial conditions for the simulations were constructed from angiographic images of a real patient with an aneurysm. The wall shear stresses, pressure and highest velocity within the artery, and other particular quantities are calculated which are of medical specific interest. The numerical simulations of the cerebral circulation help doctors to determine if the patient’s own vascular anatomy has the conditions to allow arterial stenting by endovascular method before the surgery or even evaluate the effect of different stent structure and materials. The results show that the flow downstream the aneurysm is highly modified by the stent configuration and that the best choice for reducing the flow in the aneurysm is to use a completely extended Endeavor stent.

关键词： Brain Vascular Flow Aneurysms Blood Flow Particle Methods Numerical Modeling

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New insights into the role of intra-tumor genetic heterogeneity in carcinogenesis: identification of complex single gene variance within tumors

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Journal of Cancer Metastasis and Treatment 2018年第1期4卷 428-441页

作者： Bruce Gottlieb Farbod Babrzadeh Kathleen Klein Oros carlos alvarado Chunlin Wang Baback Gharizadeh Mark Basik Celia MTGreenwood Lenore KBeitel Mark Trifiro Lady Davis Institute for Medical Research Jewish General HospitalMontrealQC H3T 1E2Canada Segal Cancer Centre Jewish General HospitalMontrealQC H3T 1E2Canada Department of Human Genetics McGill UniversityMontrealQC H3A 0G4Canada Stanford Genome Technology Center Stanford UniversityPalo AltoCA 94304USA Department of Medicine McGill UniversityMontrealQC H3A 0G4Canada

Aim:Present cancer hypotheses are almost all based on the concept that accumulation of specific driver gene mutations cause *** discovery of intra-tumor genetic heterogeneity(ITGH),has resulted in this hypothesis being modified by assuming that most of these ITGH mutations are in passenger *** addition,accumulating ITGH data on driver gene mutations have revealed considerable genotype/phenotype *** study proposes to investigate this disconnect by examining the nature and degree of ITGH in breast ***:ITGH was examined in tumors using next generation sequencing of up to 68,000 reads and analysis tools that allowed for identification of distinct minority variants within single genes,i.e.,complex single gene variance(CSGV).Results:CSGV was identified in the androgen receptor genes in all breast tumors ***:Evidence of CSGV suggests that a selection-as opposed to a mutation-centric hypothesis could better explain *** hypothesis proposes that tumors develop by the selection of preexisting de novo mutations rather than just the accumulation of de novo ***,the role of selection pressures,such as changes in tissue microenvironments will likely be critical to our understanding of tumor resistance as well as the development of more effective treatment protocols.

关键词： Intra-tumor genetic heterogeneity breast cancer complex single gene variance

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Botulinum Toxin A, Effect on Tensile Strength of Skin Wounds;Animal Study

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Journal of Biosciences and Medicines 2020年第2期8卷 17-24页

作者： carlos A. Gonzalez-alvarado Juan Garzon-Muvdi Roxanna Perez-Garmendia Victoria Ramirez Luz Graciela Cervantes Adriana Rodriguez-Gomez Rodrigo Davila-Diaz Cuahutemoc Marquez-Espriella Plastic and Reconstructive Surgery Division Hospital Central Sur de alta Especialidad de Petroleos Mexicanos Mexico City Mexico Experimental Surgery Department Instituto Nacional de Ciencias Medicas y Nutrición Salvador Zubiran Mexico City Mexico Pharmacology Department Instituto Nacional de Cardiologia Ignacio Chavez Mexico City Mexico Pathology Department Hospital Angeles del Pedregal Mexico City Mexico

Wound healing and cicatrization is a process that involves several phases. The main goal of a surgeon and specially the plastic surgeon is to achieve the best cosmetic results and avoid complications. Several tools are available to achieve the best result. One of the tools recently studied is the use of Botulinum toxin. The use of Botulinum toxin has showed to be a useful aid by improving macroscopic cosmetic changes, as histopathologic ones. The increase of the tensile strength is also one of the positive changes that come with the use of botulinum toxin.

关键词： Botulinum Toxin Wound Tensile Strength

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The significance of U-Pb zircon ages in zoned plutons:the case of the Flamenco pluton, Coastal Range batholith, northern Chile

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Geoscience Frontiers 2019年第3期10卷 1073-1099页

作者： Natalia Rodríguez Juan Díaz-alvarado carlos Fernández Paulina Fuentes Christoph Breitkreuz Colombo Celso Gaeta Tassinari Departamento de Geología Universidad de Atacama Departamento de Ciencias de la Tierra Universidad de Huelva Institut für Geologie TU Bergakademie Freiberg High Resolution Geochronological Laboratory University of S?o Paulo

Compositionally zoned plutons, both layered and concentrically arranged, provide granitic exposures where the mechanisms and timing of the magmatic emplacement processes can be studied. The importance of in-situ geochemical differentiation and the magma replenishment rates are revealed by geochemistry and field relations, together with the increasingly accurate U-Pb geochronology, which has promoted the knowledge about the pluton incremental assembly *** Flamenco pluton, located in the Coastal Range of northern Chile, is part of the Upper Triassic to Early Cretaceous Andean intrusives formed in the western active margin of South America, and present a normal zoned structure with mafic magmatic facies(mostly gabbros and Qtz-diorites) close to the contacts with the host metasediments, and tonalites, granodiorites and granites in the inner areas. A combined study of the field relations, geochemistry and zircon geochronology of the magmatic facies was applied to determine the emplacement sequence of the Flamenco pluton, revealing three distinguishable domains separated by metasedimentary septa. The SW area is constituted by mostly homogeneous leucocratic granodiorites that yielded an age of 213 Ma as the best estimation for their emplacement age. Distinctive geochemical characteristics, such as the absence of an Eu anomaly, the depletion in HREE, or the highest Sr, Sr/Y and Ce/Yb values among the granodioritic facies of the pluton,involve lower T and/or higher P conditions at the magmatic source according to experimental *** conditions were established during an early stage of the Andean magmatic arc building that is firstly defined here as Upper Triassic. The NW and E domains of the pluton were sequentially emplaced between 194 Ma and 186 Ma and both the field relations and the detailed geochronological results suggest that the mafic facies intruded latter in the emplacement sequence. To the NW, Qtz-dioritic and gabbroic externally emplaced pulses ga

关键词： Zircon U-Pb geochronology Zoned plutons Andean magmatic arc Sequential emplacement Individual and statistical zircon ages

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DNA Barcodes in Fig Cultivars (Ficus carica L.) Using ITS Regions of Ribosomal DNA, the psbA-trnH Spacer and the matK Coding Sequence

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American Journal of Plant Sciences 2015年第1期6卷 95-102页

作者： carlos Castro Alejandro Hernandez Luis alvarado Dora Flores Agribiotecnología de Costa Rica S.A. Alajuela Costa Rica Instituto Tecnológico de Costa Rica (ITCR) Cartago Costa Rica

Molecular markers provide a useful method for genotype characterization and allow a high precision determination of the genetic relationship between cultivars and varieties. A system based on DNA sequences—which is known as DNA barcoding—will choose one or several standard loci which can be sequenced and compared to differentiate between species. In this research, the ITS, matK, and trnH-psbA sequences were evaluated for the molecular identification of seven F. carica genotypes, generating complete sequences for the first two loci, but unable to produce bidirectional sequences by using the trnH-psbA sequence. The ITS sequence presented the highest variation rates, while the phylogeny constructed with the matK sequence obtained the highest percentage of solved monophyletic groups. Through Pearson’s correlation analysis, it was possible to determine the existence of a significant correlation between the ITS region and psbA-trnH, and the matK and psbA-trnH sequences, but not between ITS and matK. The phylogenies constructed with the ITS + matK barcodes and ITS + matK + psbA-trnH presented the highest percentage for resolution. However, considering the cost efficiency and the facilitated recovery by using PCR, the matK + ITS combination is recommended.

关键词： Ficus carica DNA Barcodes ITS psbA-trnH matK

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Toll-like receptor 4 polymorphisms and bacterial infections in patients with cirrhosis and ascites

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World Journal of Hepatology 2018年第1期10卷 124-133页

作者： Edilmar alvarado-Tapias carlos Guarner-Argente Elida Oblitas Elisabet Sánchez Silvia Vidal Eva Román Mar Concepción Maria Poca Cristina Gely Oana Pavel Juan Camilo Nieto Cándido Juárez carlos Guarner Germán Soriano Department of Gastroenterology Hospital de la Santa Creu i Sant PauBarcelona 08025Spain Instituto de Salud carlos III Institut de Recerca IIBSant PauUniversitat Autònoma de BarcelonaBellaterra(Cerdanyola del Vallès)08193Spain Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas(CIBERehd) Instituto de Salud Carlos IIIMadrid 28029Spain Department of Immunology Hospital de la Santa Creu i Sant PauBarcelona 08025Spain Escola Universitària d’Infermeria EUI-Sant Pau Hospital de la Santa Creu i Sant PauBarcelona 08025Spain

AIM To assess the relationship between the presence of toll-like receptor 4(TLR4) polymorphisms and bacterial infections in cirrhotic patients with ascites. METHODS We prospectively included consecutive patients with cirrhosis and ascites hospitalized during a 6-year period. Patients with human immunodeficiency virus(HIV) infection or any other immunodeficiency, patients with advanced hepatocellular carcinoma(beyond Milan's criteria) or any other condition determining poor short-term prognosis, and patients with a permanent urinary catheter were excluded. The presence of D299 G and/or T399 I TLR4 polymorphisms was determined by sequencing and related to the incidence and probability of bacterial infections, other complications of cirrhosis, hepatocellular carcinoma, and mortality during follow-up. A multivariate analysis to identify predictive variables of mortality in the whole series was performed. RESULTS We included 258 patients: 28(10.8%) were carriers of D299G and/or T399I TLR4 polymorphisms(polymorphism group) and 230 patients were not(wildtype group). The probability of developing any bacterial infection at one-year follow-up was 78% in the polymorphism group and 69% in the wild-type group(P = 0.54). The one-year probability of presenting infections caused by gram-negative bacilli(51% vs 44%, P = 0.68), infections caused by gram-positive cocci(49% vs 40%, P = 0.53), and spontaneous bacterial peritonitis(29% vs 34%, respectively, P = 0.99) did not differ between the two groups. The oneyear probability of transplant-free survival was 55% in the polymorphism group and 66% in the wild-type group(P = 0.15). Multivariate analysis confirmed that age, Child-Pugh score, active alcohol intake, previous hepatic encephalopathy, hepatocellular carcinoma and serum creatinine were associated with a higher risk of death during follow-up. CONCLUSION Genetic polymorphisms D299 G and/or T399 I of TLR4 do not seem to play a relevant role in the predisposition of cirrhotic patie

关键词： Cirrhosis Genetic polymorphisms Toll-like receptor 4 Bacterial infections Ascites

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Nucleation and growth kinetics of La0.7Sr0.3Cr0.4Mn0.6O3-δ SOFC perovskite:Symmetry alteration evolution induced by Cu2+ and Ni2+ impregnation

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Progress in Natural Science:Materials International 2016年第6期26卷 665-670页

作者： A.Concha-Balderrama G.Rojas-George J.alvarado-Flores H.Esparza-Ponce M.H.Bocanegra-Bernal A.Reyes-Rojas Centro de Investigación en Materiales Avanzados S.C.(CIMAV) Laboratorio Nacional de NanotecnologíaMiguel de Cervantes 120 Complejo Industrial ChihuahuaCd.de Chihuahua

La0.7Sr0.3Cr0.4Mn0.6O3-δperovskite nanoparticles have been synthetized using an ethylene glycol modified solgel method and impregnated by Cu0.75Ni0.25nanoparticles. The phase transitions and nucleation kinetics were studied by time resolved x-ray diffraction, Rietveld, Raman spectroscopy and high resolution transmission electron microscopy. Findings have shown that, an atomic disorder dominates from room temperature to 400 °C. Nanoparticles with crystal size < 26 nm start through nuclei formation of La0.7Sr0.3Cr0.4Mn0.6O3-δand SrCrO4solid solutions with Pm3m cubic and P21/n monoclinic symmetry respectively in the range of 600–650 °C. Symmetry reduction from the Pm3m→R3c space group had been obtained at a lower temperature（750 °C） than those reported in the literature in oxygen atmosphere and it was confirmed by an octahedral distortion, which takes place in the crystallographic direction[221]/（122）. The Johnson-Mehl-Avrami model had described the whole process, where the existence of two phases was shown before it reached its complete D3d6point group symmetry.

关键词： Perovskite structure Sol-gel method Composite Kinetics Rietveld

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Effects of anatomical position on esophageal transit time:A biomagnetic diagnostic technique

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World Journal of Gastroenterology 2008年第37期14卷 5707-5711页

作者： Teodoro Cordova-Fraga Modesto Sosa carlos Wiechers Jose Maria De la Roca-Chiapas Alejandro Maldonado Moreles Jesus Bernal-alvarado Raquel Huerta-Franco Instituto de Física Universidad de GuanajuatoLeón 37150 Gto. Mexico Instituto de Investigaciones sobre el Trabajo Universidad de GuanajuatoLeón 37150 Gto. Mexico

AIM: To study the esophageal transit time (ETT) and compare its mean value among three anatomical inclinations of the body; and to analyze the correlation of ETT to body mass index (BMI). METHODS: A biomagnetic technique was implemented to perform this study: (1) The transit time of a magnetic marker (MM) through the esophagus was measured using two fluxgate sensors placed over the chest of 14 healthy subjects; (2) the ETT was assessed in three anatomical positions (at upright, fowler, and supine positions; 90o, 45o and 0o, respectively). RESULTS: ANOVA and Tuckey post-hoc tests demonstrated significant differences between ETT mean of the different positions. The ETT means were 5.2 ± 1.1 s, 6.1 ± 1.5 s, and 23.6 ± 9.2 s for 90o, 45o and 0o, respectively. Pearson correlation results were r = -0.716 and P 0.05 according the subject's BMI. CONCLUSION: We demonstrated that using this biomagnetic technique, it is possible to measure the ETT and the effects of the anatomical position on the ETT.

关键词：食道经过时间解剖结构生物磁学诊断技术

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