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Recombinant streptokinase vs phenylephrine-based suppositories in acute hemorrhoids, randomized, controlled trial(THERESA-3)

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World Journal of Gastroenterology 2014年第6期20卷 1594-1601页

作者： Francisco hernández-Bernal Georgina Castellanos-Sierra Carmen m Valenzuela-Silva Karem m Catasús-lvarez Roselin Valle-Cabrera Ana Aguilera-Barreto pedro A López-Saura Center for Genetic Engineering and Biotechnology "Juan B. Zayas" Hospital National Center for the Coordination of Clinical Trials

AIm: To compare the efficacy and safety of recombinant streptokinase (rSK) and phenylephrine-based suppositories in acute hemorrhoidal disease.

关键词： Streptokinase Suppository Phenylephrine Thrombolysis Hemorrhoids Randomized clinical trial

Regulation of floral senescence in Arabidopsis by coordinated action of CONSTANS and jasmonate signaling

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molecular Plant 2022年第11期15卷 1710-1724页

作者： Gloria Serrano-Bueno pedro de los Reyes Andrea Chini Gabriel Ferreras-Garrucho Víctor Sánchez de medina-hernández marta Boter Roberto Solano Federico Valverde Plant Development Group Institute for Plant Biochemistry and PhotosynthesisCSIC-Universidad de Sevilla41092 SevillaSpain Department of Plant molecular Genetics Centro Nacional de BiotecnologíaCSIC28049 MadridSpain Crop Science Centre University of CambridgeCambridge CB3 OLE CambridgeUK Gregor mendel Institute(GmI) Austrian Academy of SciencesVienna BioCenter(VBC)ViennaAustria

In Arabidopsis,photoperiodic flowering is controlled by the regulatory hub gene CONSTANS(CO),whereas floral organ senescence is regulated by the jasmonates(JAs).Because these processes are chronologically ordered,it remains unknown whether there are common regulators of both *** this study,we discovered that CO protein accumulates in Arabidopsis flowers after floral induction,and it displays a diurnal pattern in floral organs different from that in the *** observed that altered CO expression could affect flower senescence and abscission by interfering with JA response,as shown by petal-specific transcriptomic analysis as well as CO overexpression in JA synthesis and signaling *** found that CO has a ZIm(ZINC-FINGER INFLORESCENCE mERISTEm)like domain that mediates its interaction with the JA response repressor JAZ3(jasmonate ZIm-domain 3).Their interaction inhibits the repressor activity of JAZ3,resulting in activation of downstream transcription factors involved in promoting flower ***,we showed that CO,JAZ3,and the E3 ubiquitin ligase COI1(Coronatine Insensitive 1)could form a protein complex in planta,which promotes the degradation of both CO and JAZ3 in the presence of *** together,our results indicate that CO,a key regulator of photoperiodic flowering,is also involved in promoting flower senescence and abscission by augmenting JA signaling and *** propose that coordinated recruitment of photoperiodic and JA signaling pathways could be an efficient way for plants to chronologically order floral processes and ensure the success of offspring production.

关键词： CONSTANS flower senescence jasmonic acid

modeling Operational Parameters for Uranium Dioxide Production Reactor through Uranium Trioxide Reaction Using Hydrogen

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World Journal of Nuclear Science and Technology 2016年第3期6卷 131-139页

作者： pedro Orrego José hernández Jorge manríquez Sección de Geología y minería Departamento de Materiales Nucleares Comisión Chilena de Energía Nuclear Santiago Chile Ingeniería Civil metalurgia Universidad de Santiago de Chile Santiago Chile

This article shows the modeling of a uranium dioxide production reactor using COmSOL multiphysics software program in its 4.3b version. The model was made using 3 kinds of studies: momentum, heat and mass transport, in order to determine the influence of the most important operational parameters: UO3 reaction rate, composition and flow of the reduction gas, the initial temperature reactor and the reducing gas. The operational parameters evaluated were the followings: constant gas flow of2.5 L/min, initial hydrogen concentration of 0.25, 0.50 and0.75 m, and initial temperature of 400°C. The obtained results allow to conclude that under these working conditions, uranium dioxide is obtained virtually instantaneous and, with concentrations close to 0.5 m H2 in the reducing gas, the process can operate continuously and autogenously, without applying additional energy and temperatures around 600°C.

关键词： Uranium Trioxide Uranium Dioxide Conversion modeling

Recruitment Age of Litopenaeus vannamei (Boone, 1931) (Decapoda: Penaeidae) in the Cabeza De Toro-La Joya Buenavista Lagoon System, Oaxaca-Chiapas, mexico

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Open Journal of marine Science 2017年第4期7卷 511-525页

作者： pedro Cervantes- hernández Pablo Torres- hernández mario Alejandro Gómez- Ponce Institutos de Recursos Universidad del Mar Carretera a Zipolite Puerto ángel México Instituto de Industrias Universidad del Mar Carretera a Zipolite Puerto ángel México Instituto de Ciencias del mar y Limnología Universidad Nacional Autónoma de México (Estación El Carmen) Ciudad del Carmen México

At present, the fishery of Litopenaeus vannamei continues overexploited in the Gulf of Tehuantepec (GT), mexico. From the available literature it was demonstrated that marine closure systems implemented in GT have not worked adequately since 1993, because these are completely protecting marine recruitment seasons, and reproductive seasons were only partially considered to protect. Due to these problems, new marine closure systems were proposed in the literature, but they were not accepted by fishermen from GT because they did not include marine and lagoon recruitment information. For this reason, in this study both recruitment types were analyzed with estimations on the recruitment age (RA), and its relationship with total length and weight. To the Cabeza de Toro la Joya Buenavista lagoon system (CTJB-LS), it was concluded that young recruits migration toward outside CTJB-LS elapsed between 3 and 5-m-olds, with the highest recruit flow in 4-m-olds. Thus, this last age was called the RA of L. vannamei (at 106 mm). maximum marine recruitment ranked from June to July, and maximum reproductive seasons were in October. In both recruitment seasons it was observed that biomass production was different. In marine season RA recorded 8.4 g more than lagoon season at the same size. Results were used in order to discus about atarraya nets uses, and to propose the implementation of a lagoon closure during July inside lagoon systems located in GT. With this proposal artisanal fishermen will be allowed to use atarraya nets with mesh opening of 25.4 mm during June, and they will obtain a good biomass production level as economic ***, with new marine closure systems shrimp reproductive seasons will be protected (from July to November).

关键词： Closure Systems Gulf of Tehuantepec Recruitment Age Recruitment Seasons White Shrimp

metal-modulated epitaxy of mg-doped Al_(0.80)In_(0.20)N-based layer for application as the electron blocking layer in deep ultraviolet light-emitting diodes

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Journal of Semiconductors 2024年第5期45卷 80-89页

作者： Horacio Irán Solís-Cisneros Carlos Alberto hernández-Gutiérrez Enrique Campos-González máximo López-López Optomechatronics Group Tecnológico Nacional de México Campus Tuxtla Gutiérrezcarretera Panamericana 1080C.P.29050Tuxtla GutiérrezChiapasMéxico Departamento de Física Instituto Nacional de Investigaciones NuclearesCarretera México-Toluca s/nC.P.52750La Marquesa OcoyoacacMéxico Departamento de Física Centro de Investigación y estudios Avanzados del Instituto Politécnico NacionalAv.Instituto Politécnico Nacional 2508San Pedro ZacatencoGustavo A.Madero07360 Ciudad de MéxicoCDMXMéxico

This work reports the growth and characterization of p-AlInN layers doped with mg by plasma-assisted molecular beam epitaxy(PAmBE).AlInN was grown with an Al molar fraction of 0.80 by metal-modulated epitaxy(mmE)with a thickness of 180 nm on Si(111)substrates using AlN as buffer *** substrate temperatures were used to enhance the incorporation of indium atoms into the alloy without clustering,as confirmed by X-ray diffraction(XRD).Cathodoluminescence measurements revealed ultraviolet(UV)range ***,Hall effect measurements indicated a maximum hole mobility of 146 cm^(2)/(V∙s),corresponding to a free hole concentration of 1.23×10^(19)cm^(−3).The samples were analyzed by X-ray photoelectron spectroscopy(XPS)estimating the alloy composition and extracting the Fermi level by valence band ***-doped AlInN layers were studied for use as the electron-blocking layer(EBL)in LED *** varied the Al composition in the EBL from 0.84 to 0.96 molar fraction to assess its theoretical effects on electroluminescence,carrier concentration,and electric field,using SILVACO *** results from this study highlight the importance and capability of producing high-quality mg-doped p-AlInN layers through *** simulations suggest that an Al content of 0.86 is optimal for achieving desired outcomes in electroluminescence,carrier concentration,and electric field.

关键词： metal-modulated epitaxy AlInN DUV-LED EBL simulation

Reduction Kinetics of Uranium Trioxide to Uranium Dioxide Using Hydrogen

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World Journal of Nuclear Science and Technology 2015年第3期5卷 149-156页

作者： pedro Orrego Alfaro José hernández Torres Fernando Puchi Thiele Sección de Geología y minería Departamento de Materiales Nucleares Comisión Chilena de Energía Nuclear Santiago Chile Ingeniería Civil metalurgia Universidad Andrés Bello Santiago Chile

This article presents a study on the kinetics of the uranium conversion process, consisting in the reduction of uranium trioxide to uranium dioxide using hydrogen gas at temperatures of 500°C, 600°C and 700°C. Hydrogen concentrations used in the flow were 0.25 m, 0.50 m and 0.75 m. The mechanism established for the study of the kinetics of reduction of uranium trioxide was through the formation of an intermediate compound, U3O8. For this reason, these tests were divided into 2 stages: the first one the reduction from UO3 to U3O8, and second one from U3O8 to UO2. The results of each test were quantified by the release of H2O(g) produced by both reactions. Tests showed that the ideal working conditions are for hydrogen concentration flows of 0.75 m and temperatures in the range of 500°C - 600°C, with the intent to decrease the occurrence of side reactions that interfere with the process.

关键词： Conversion Uranium Oxides Nuclear Fuel Cycle

Hydrothermal Synthesis and Characterization of Europium-doped Barium Titanate Nanocrystallites

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Nano-micro Letters 2013年第1期5卷 57-65页

作者： margarita García-hernndez Geneviève Chadeyron Damien Boyer Antonieta García-murillo Felipe Carrillo-Romo Rachid mahiou Universidad Autónoma metropolitana Departamento de Ciencias NaturalesDCNIUnidad CuajimalpaPedro Antonio de los Santos 8411850 Mxico D.F. Mxico Clermont Universit Institut de Chimie de Clermont-Ferrand UMR 6296CNRS/UBP/ENSCCFBP 10448F-63000 Clermont-Ferrand Instituto Politcnico Nacional CIITEC IPNCerrada de Cecati S/N. Col. Santa CatarinaAzcapotzalco Mxico D.F. C.P. 02250Mxico

Barium titanate nanocrystallites were synthesized by a hydrothermal technique from barium chloride and tetrabutyl titanate. Single-crystalline cubic perovskite Ba TiO_3 consisting of spherical particles with diameters ranging from 10 to 30 nm was easily achieved by this route. In order to study the influence of the synthesis process on the morphology and the optical properties, barium titanate was also prepared by a solid-state reaction. In this case, only the tetragonal phase which crystallizes above 900 was observed. High-temperature X-ray diffraction measurements were performed to investigate the crystallization temperatures as well as the particle sizes via the Scherrer formula. The lattice vibrations were evidenced by infrared spectroscopy. Eu^(3+)was used as a structural probe, and the luminescence properties recorded from Ba TiO_3 :Eu^(3+)and elaborated by a solid-state reaction and hydrothermal process were compared. The reddish emission of the europium is increased by the nanometric particles.

关键词： BaTiO3 Europium Nanocrystallites Hydrothermal technique

Evaluation of multiplicative Weight of Covariance matrix on Hybrid Data Assimilation Schemes

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Atmospheric and Climate Sciences 2023年第2期13卷 255-281页

作者： pedro m. González-Jardines maibys Sierra-Lorenzo Adrián L. Ferrer-hernández Center for Atmospheric Physics Institute of Meteorology Havana Cuba

This research develops a comparative study between different multiplicative weights that are assigned to the covariance matrix that represents the background error in two hybrid assimilation schemes: 3DEnVAR and 4DEnVAR. These weights are distributed between the static and time-invariant matrix and the matrix generated from the perturbations of a previous ensemble. The assigned values are 25%, 50%, and 75%, always having as a reference the ensemble matrix. The experiments are applied to the short-range Prediction System (SisPI) that works operationally at the Institute of meteorology. The impact of Tropical Storm Eta on November 7 and 8, 2020 was selected as a study case. The results suggest that by giving the main weight to the ensemble matrix more realistic solutions are achieved because it shows a better representation of the synoptic flow. On the other hand, it is observed that 3DEnVAR method is more sensitive to multiplicative weight change of the first guess. more realistic results are obtained with 50% and 75% relations with 4DEnVAR method, whereas with 3DEnVAR a weight of 75% for the ensemble matrix is required.

关键词： SisPI WRFDA Hybrid-methods Covariance Weights

Structural studies of BaTiO_3:Er^(3+) and BaTiO_3:Yb^(3+) powders synthesized by hydrothermal method

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Journal of Rare Earths 2014年第11期32卷 1016-1021页

作者： Garrido-hernández A García-murillo A Carrillo-Romo F de J Cruz-Santiago L A Chadeyron G morales-Ramírez A de J Velumani S T.A. Post-graduate Student. Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F México Instituto Politécnico Nacional CIITEC IPN Cerrada de Cecati S/N. Col. Santa Catarina Azcapotzalco México D.F. C.P. 02250 México D.F Departament of Engineering materials Tecnológico de Estudios Superiores de Coacalco (TESCo) Av. 16 de Septiembre # 54 Cabecera Municipal C.P. 55700 Coacalco de Berriozábal Estado de México Institut de Chimie de Clermont-Ferrand UMR 6296 CNRS / UBP / ENSCCF 24 avenue des Landais BP 80026 63171 Aubière Cedex – France Department of Electrical Engineering (SEES) Centro de Investigación y de Estudios Avanzados del IPN Av. Instituto Politécnico Nacional 2508 Col. San Pedro Zacatenco C.P. 07360 Mexico D.F. Mexico

Erbium and ytterbium doped barium titanate nanopowders were prepared using the hydrothermal method. A barium titanate structure doped with rare earth ions manifested new characteristics and improved the field of application of optical devices such as trichromatic tubes, LCD displays, lamps, and infrared lasers. In this work, BaTiO3：Er3＋ and BaTiO3：Yb3＋ were prepared using barium chloride [BaCl2], titanium butoxide [C16H36O4Ti], erbium chloride [ErCl3] and ytterbium chloride [YbCl3] as precursors. Anhydrous methanol was employed as a solvent. metallic potassium was used to promote solubility in the system and increase the pH to 13. This method yielded the formation of a predominantly cubic structure in both Er3＋ and Yb3＋ doped BaTiO3 powders. Characteristic bondings of BaTiO3 were observed with FT-IR spectroscopy. The predominantly cubic structure was confirmed by X-ray diffraction and micro-Raman analyses. The particle size（～30 nm） was estimated using the Scherrer equation and X-ray diffraction data. The results were presented and discussed.

关键词： nanopowders hydrothermal BaTiO3:Er3+ BaTiO3:Yb3+ rare earths