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Chromatographic fingerprinting and free-radical scavenging activity of ethanol extracts of Muntingia calabura L. leaves and stems

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Asian Pacific Journal of Tropical Biomedicine 2017年第2期7卷 139-143页

作者： William Patrick Cruiz Buhian Raquel Orejudos rubio Juliana Janet Martin-Puzon Biological Research and Services Laboratory Natural Sciences Research InstituteUniversity of the PhilippinesDilimanQuezon City 1101Philippines Institute of Biology University of the PhilippinesDilimanQuezon City 1101Philippines

Objective: To determine the thin-layer chromatography(TLC) fingerprint profiles and to evaluate the in vitro antioxidant activity of ethanol extracts of Muntingia calabura(M. calabura) leaves and ***: The leaves and stems were extracted using ethanol as solvent. The TLC separation of the phytochemical constituents of the leaf and ethanol extracts was carried out in ethyl acetate: n-hexane and chloroform: ethyl acetate mobile phase *** spots were visualized under visible light, UV 254 nm, UV 366 nm and after spraying with vanillin-sulfuric acid. The 2,2-diphenyl-1-picrylhydrazyl free-radical scavenging assay was used to evaluate the antioxidant activity of the ***: Both the leaf and stem ethanol extracts at 4 mg/mL exhibited 2,2-diphenyl-1-picrylhydrazyl inhibition of more than 90%, relative to gallic acid. The results of TLC showed that the degree of resolution between the constituent spots was comparable between the two mobile phase systems using the different visualization wavelengths. Under the 254 nm visualization, few spots were observed in leaf and stem extracts. Visualization at 366 nm yielded the greatest number of observable spots of various colors in both leaf and stem extracts. More spots were visualized upon post-derivatization with vanillinsulfuric acid in the TLC chromatograms using chloroform: ethyl acetate mobile phase,compared to those in ethyl acetate: n-hexane mobile ***: M. calabura exhibited very high antioxidant activity in its leaves and stems ethanol extracts, both of which are used in traditional medicine. The TLC results demonstrated the presence of diverse secondary metabolites in the leaf and stem ethanol extracts, indicating that the antioxidant activity, including other bioactivities may be attributed to these phytochemical constituents. This paper has reported for the first time the TLC fingerprinting of M. calabura using visible light, UV 254 nm, UV 366 and postderivatization with vani

关键词： Muntingia calabura Antioxidant DPPH Thin-layer chromatography Secondary metabolites

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Software Project Effort Estimation Based on Multiple Parametric Models Generated Through Data Clustering

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Journal of Computer Science & Technology 2007年第3期22卷 371-378页

作者： Juan J.Cuadrado Gallego Daniel Rodríguez Miguel Angel Sicilia Miguel Garre rubio Angel García Crespo Department of Computer Science The University of Alcalá AlcaláSpain Department of Computer Science Carlos Ⅲ University.Madrid Spain

Parametric software effort estimation models usually consists of only a single mathematical relationship. With the advent of software repositories containing data from heterogeneous projects, these types of models suffer from poor adjustment and predictive accuracy. One possible way to alleviate this problem is the use of a set of mathematical equations obtained through dividing of the historical project datasets according to different parameters into subdatasets called partitions. In turn, partitions are divided into clusters that serve as a tool for more accurate models. In this paper, we describe the process, tool and results of such approach through a case study using a publicly available repository, ISBSG. Results suggest the adequacy of the technique as an extension of existing single-expression models without making the estimation process much more complex that uses a single estimation model. A tool to support the process is also presented. Keywords software engineering, software measurement, effort estimation, clustering

关键词： software engineering software measurement effort estimation clustering

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State of the Art on Micromilling of Materials,a Review

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Journal of Materials Science & Technology 2012年第8期28卷 673-685页

作者： M.A.Cmara J.C. Campos rubio A.M. Abro J.P. Davim Department of Mechanical Engineering Universidade Federal de Minas GeraisAv.Ant onio Carlos6627-Pampulha Belo Horizonte MGCEP:31.270-901Brazil Department of Mechanical Engineering University of AveiroCampus Universitrio de Santiago3810-193AveiroPortugal

The trend towards miniaturization has increased dramatically over the last decade, especially within the fields concerned with bioengineering, microelectronics, and aerospace. Micromillin8 is among the principal manu- facturing processes which have allowed the development of components possessing micrometric dimensions, being used to the manufacture of both forming tools and the final product. The aim of this work is to present the principal aspects related to this technology, with emphasis on the work material requirements, tool ma- terials and geometry, cutting forces and temperature, quality of the finished product, process modelling and monitoring and machine tool requirements. It can be noticed that size effect possesses a relevant role with regard to the selection of both work material （grain size） and tooling （edge radius）. Low forces and temper- ature are recorded during micromillin8, however, the specific cutting force may reach high values because of the ploughing effect observed as the uncut chip thickness is reduced. Finally, burr formation is the principal concern with regard to the quality of the finished part.

关键词： Micro-milling Micromachining Size effect Miniaturization

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Need for infliximab dose intensification in Crohn's disease and ulcerative colitis

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World Journal of Gastroenterology 2014年第27期20卷 9170-9177页

作者： Carlos Taxonera David Olivares Juan L Mendoza Manuel Díaz-rubio Enrique Rey Inflammatory Bowel Disease Unit Department of Gastroenterology Hospital Clínico San Carlos Instituto de Investigación del Hospital Clínico San Carlos (IdISSC) Department of Gastroenterology Hospital Clínico San Carlos

AIM: To compare the need for infliximab dose intensification in two cohorts of patients with Crohn’s disease (CD) or ulcerative colitis (UC).

关键词： Crohn's disease Ulcerative colitis Infliximab Dose intensification Costs

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Demographic histories of three predatory lady beetles reveal complex patterns of diversity and population size change in the United States

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Insect Science 2018年第6期25卷 1065-1079页

作者： Arun Sethuraman Fredric J.Janzen Michael A.rubio Yumary Vasquez John J.Obrycki Department of Biological Sciences Cafifomia State University San MarcosSan MarcosCaliforniaUSA Department of Ecology Evolution and Organismal BiologyIowa State UniversityAmesIowaUSA Department of Entomology University of KentuckyLexingtonKentuckyUSA

Predatory lady beetles (Coccinellidae)contribute to biological control of agri- cultural pests,however,multiple species frequently compete for similar resources in the same *** studies have examined ecological interactions among the native North American convergent lady beetle (Hippodamia convergens)and two intro- duced species,the seven-spotted lady beetle (Coccinella septempunctata)and the Asian lady beetle (Harmonia axyridis),in agricultural fields and described multiyear population ***,the evolutionary dynamics of these interacting species of predatory beetles are *** utilize publicly available multilocus genotype data from geographically disjunct populations of these three species to estimate demography across North American *** analyses reveal (1)a recent (4-5years)decline (>12 fold)in microsatellite effective population size ***,while expanding (mutation scaled growth rate in 1/u generations =2910,SD =362)over evolutionary time scales,(2)a massive (>150 fold),and very recent,effective population size decline in Ha. axyridis,and (3)population size growth (mutation scaled growth rate =997,SD =60)over recent and evolutionary time scales in *** these estimates are based on genetic data with different mutation rates and patterns of inheritance (mitochondrial versus nuclear),these dynamic and differing population size histories are striking. Further studies of the interactions of these predatory lady beetles in the field are thus warranted to explore the consequences of population size change and biological control activities for evolutionary trajectories in North America.

关键词： biological control bottleneck demography effective population size inva- siveness predatory lady beetles

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Open Cows in a Beef Cattle Enterprise Managed in a Seasonal Breeding Program? An Appraisal of Their Reproductive Performance Based on Body Fat Reserves

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Open Journal of Veterinary Medicine 2022年第5期12卷 37-48页

作者： josé Francisco Martínez Pablo Ortiz Carlos Salvador Galina Manuel Corro Ivette rubio Libia Pérez-Torres Departamento de Reproducción Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autónoma de México Ciudad de México México Centro de Enseñ anza Investigación y Extensión en Ganadería Tropical Facultad de Medicina Veterinaria y Zootecnia Universidad Nacional Autónoma de México Tlapacoyan México Facultad de Medicina Veterinaria y Zootecnia Universidad Autónoma de Tamaulipas Ciudad Victoria México

A comparison between two distinct levels of back fat thickness in open cows, females not becoming pregnant during the previous breeding season, was carried out in order to evaluate their reproductive performance prior to the next natural mating in a seasonal breeding program. Thirty open cows from the previous breeding season were divided evenly by age and back fat thickness (BFT) in two groups. HBFT (high back fat thickness ≥ 70 mm) and LBFT (low back fat thickness ≤ 70 mm), values statistically different between groups (P < 0.05). The study was divided into three phases in which the formation of CL and follicular dynamics were recorded by ultrasound and progesterone. Also, serial monitoring of glucose, urea and triglycerides and back fat thickness were studied. A fertile bull previously approved from a breeding soundness evaluation was introduced after the third phase and remained with the herd for 90 days. No differences were found in the follicular dynamics;the number of animals cycling in the two groups and fertility were also similar (80%). Differences in urea and triglycerides were found in cows with high scores of BFT. In conclusion, the decision of keeping open cows to the next breeding season must be based on an economical advantage to the farmer.

关键词： Back Fat Thickness Corpus Luteum Follicular Dynamics Tropics Zebu Cattle

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Dynamical amplification of electric polarization through nonlinear phononics in 2D SnTe

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npj Computational Materials 2020年第1期6卷 155-162页

作者： Dongbin Shin Shunsuke A.Sato Hannes Hübener Umberto De Giovannini Noejung Park Angel rubio Max Planck Institute for the Structure and Dynamics of Matter and Center for Free-Electron Laser Science Luruper Chaussee 149Hamburg 22761Germany Center for Computational Sciences University of TsukubaTsukuba 305-8577Japan Nano-Bio Spectroscopy Group Departamento de Fisica de MaterialesUniversidad del Pas VascoSan Sebastian 20018Spain Department of Physics Ulsan National Institute of Science and TechnologyUNIST-gil 50Ulsan 44919Korea Center for Computational Quantum Physics(CCQ) The Flatiron Institute162 Fifth AvenueNew YorkNY 10010USA

Ultrafast optical control of ferroelectricity using intense terahertz fields has attracted significant *** we show that the nonlinear interactions between two optical phonons in SnTe,a two-dimensional in-plane ferroelectric material,enables a dynamical amplification of the electric polarization within subpicoseconds time *** first-principles time-dependent simulations show that the infrared-active out-of-plane phonon mode,pumped to nonlinear regimes,spontaneously generates in-plane motions,leading to rectified oscillations in the in-plane electric *** suggest that this dynamical control of ferroelectric material,by nonlinear phonon excitation,can be utilized to achieve ultrafast control of the photovoltaic or other nonlinear optical responses.

关键词： nonlinear ferroelectric phonon

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Differences in seed dormancy and germination in amphicarpic legumes:manifold bet-hedging in space and time

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Journal of Plant Ecology 2021年第4期14卷 662-672页

作者： Ricardo Sanchez-Martin jose Maria Gomez Pierre-Olivier Cheptou Rafael rubio de Casas Departamento Ecologia Vegetal Centro de Investigaciones sobre Desertificacion(CIDE-CSIC-UV-GV)Carretera de Moncada-Naquera Km 4546113 MoncadaValenciaSpain Departamento de Ecologia Funcional y Evolutiva Estacion Experimental de Zonas AridasEEZA-CSICCtra.de Sacramento s/nLa Cañada de San Urbano04120 AlmeriaSpain Centre d’Ecologie Fonctionnelle et Evolutive(CEFE) CEFE UMR 5175CNRSUniversite de MontpellierUniversite Paul-Valery7 MontpellierEPHE1919 route de Mende34293 Montpellier Cedex 05France Departamento de Ecologia Universidad de GranadaAvda.de Fuentenueva s/n18071 GranadaSpain

Aims Dispersal through space or time via dormancy is one of the primary processes whereby organisms can influence the environment they *** plants,strong evolutionary correlations are expected between the two kinds of dispersal because both are performed by the seeds and play comparable adaptive *** this paper,we investigated these evolutionary correlations using amphicarpic plants,which simultaneously produce aerial seeds with high spatial dispersal propensity and subterranean seeds that do not *** We investigated the variation in dormancy and germination in aerial and subterranean seeds of two amphicarpic legumes(Vicia amphicarpa *** Lathyrus amphicarpos L.)and two closely related homocarpic taxa(Vicia sativa *** Lathyrus cicera L.)by estimating germination percentages following different combinations of dormancy breaking treatments(*** after-ripening,cold stratification and physical scarification).Important Findings Our results showed complex interactions between spatial and temporal *** after dispersal,aerial seeds were more dormant than their subterranean counterparts,but this trend reversed with after-ripening,as seeds developed physical *** of homocarpic plants germinated at higher percentages than those of their amphicarpic congeners and lost dormancy homogeneously with ***,amphicarpic seeds exhibited varied dormancy strategies modulated by both physiological and physical *** are expected to increase variation in emergence timing,providing multiple levels of diversifying *** strategy might be adaptive under highly unpredictable conditions by enabling plants to rely on historically favorable sites in good seasons without preventing spatial and temporal migration.

关键词： amphicarpy dormancy/colonization trade-off amphicarpic legumes environmental heterogeneity seed dormancy and germination Mediterranean environments

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Roles of Ubiquitination in the Control of Phosphate Starvation Responses in Plants

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Journal of Integrative Plant Biology 2013年第1期55卷 40-53页

作者： Mónica Rojas-Triana Regla Bustos Ana Espinosa-Ruiz Salom Prat Javier Paz-Ares Vicente rubio The Samuel Roberts Noble Foundation Department of Plant Biology 2510 Sam Noble Parkway Ardmore CBGP (INIA-UPM) Departamento de Biotecnología Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria Campus de Montegancedo Centro Nacional de Biotecnología (CNB-CSIC) Darwin

Throughout evolution, plants have evolved sophisticated adaptive responses that allow them to grow with a limited supply of phos-phate, the preferential form in which the essential macronutrient phosphorus is absorbed by plants. Most of these responses are aimed to increase phosphate availability and acquisition through the roots, to optimize its usage in metabolic processes, and to protect plants from the deleterious effects of phosphate deficiency stress. Regulation of these adaptive responses requires fine percep- tion of the external and internal phosphate levels, and a complex signal transduction pathway that integrates information on the phosphate status at the whole-plant scale. The molecular mecha-nisms that participate in phosphate homeostasis include transcriptional control of gene expression, RNA silencing mediated by microRNAs, regulatory non-coding RNAs of miRNA activity, phosphate transporter trafficking, and post-translational modification of proteins, such as phosphorylation, sumoylation and ubiquitination. Such a varied regulatory repertoire reflects the complexity intrinsic to phosphate surveying and signaling pathways. Here, we describe these regulatory mechanisms, emphasizing the increasing importance of ubiquitination in the control of phosphate starvation responses.

关键词： Phosphate homeostasis phosphate signaling phosphate starvation post-translational control ubiquitin.

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Unusual treatment of postoperative bleeding after cardiac surgery

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World Journal of Cardiovascular Diseases 2013年第5期3卷 377-379页

作者： josé rubio-Alvarez Juan Sierra-Quiroga Belén Adrio-Nazar Laura Reija López ángela Granda Bauza Carola rubio Taboada jose Manuel Martinez-Cereijo Department of Cardiac Surgery Universitary Hospital Santiago de Compostela Santiago Spain Department of Vascular Surgery Universitary Hospital of Elche Alicante Spain

A young patient was presented to the emergency department with chest pain and palpitations. A transthoracic echocardiogram showed a right atrial mass. Coronary angiography showed a right coronary artery with collateral circulation to a large mass. The tumor could only be partially resected and the patient experienced persistent postoperative bleeding. We performed a new right coronary artery angiography which showed an important free extravasation of contrast into the pericardium through the collateral circulation. Using covered stents, the bleeding was controlled. The pathological examination performed later revealed a primary cardiac angiosarcoma. After asymptom-free survival of 14 months the patient presented bone metastases.

关键词： Angiosarcoma Coronary Stenting Postoperative Bleeding

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