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Mechanical response to axial strain in WS2 nanotubes

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Progress in Natural Science:Materials International 2021年第6期31卷 898-903页

作者： S.Mejía-Rosales S.A.Sandoval-Salazar A.soria-Sánchez J.D.Vázquez-Palafox Centro de Investigación en Ciencias Físico-Matemáticas (CICFIM) Facultad de Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León Facultad de Ciencias Físico-Matem aticas Universidad Aut onoma de Nuevo León Facultad de Ciencias Físico-Matemáticas Universidad Autónoma de Nuevo León

In order to take advantage of inorganic nanotubes for their use with pragmatic purposes, characterization of their mechanical properties becomes a relevant issue. In the present study, a series of results on the mechanical properties of WS2nanotubes of several diameters and two main lattice orientations was obtained by the implementation of molecular dynamics simulations using an interatomic potential of the Stillinger-Weber kind. A Young’s modulus for nanotubes of H polytype close to 170 GPa was obtained in accordance with experimental results, and of ≈ 130 GPa for nanotubes of the T polytype, with almost no dependance on the diameter of the nanotube. The tensile strength was as large as 20 GPa(H armchair nanotubes, close to the value obtained in experiments), and the strain at the point of rupture reached values close to 0.24. The effect of several kinds of defects on the mechanical properties was investigated, and the results showed that when the defects consisted in the absence of a whole WS2unit, the tensile strength and point of rupture dropped considerably, and the fracture became more brittle than in pristine nanotubes. The dependence of the mechanical properties on temperature was also investigated.

关键词： Tungsten disulfide nanotubes Young's modulus Stillinger-weber Molecular dynamics

Development and assessment of a multifunctional chitosan-based coating applied on AZ31 magnesium alloy: Corrosion resistance and antibacterial performance against Klebsiella Pneumoniae

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Journal of Magnesium and Alloys 2021年第6期9卷 2133-2144页

作者： Emmanuel Mena-Morcillo Lucien Veleva Mariana Cerda-Zorrilla Montserrat soria-Castro Juan C.Castro-Alcátara Rosa C.Canul-Puc Applied Physics Department Center for Research and Advanced Study(CINVESTAV-IPN)Carr.Ant.a Progreso Km.697310MeridaYucatanMexico Marine Resources Department Center for Research and Advanced Study(CINVESTAV-IPN)Carr.Ant.a Progreso Km.697310MeridaYucatanMexico

This work presents a simple method to functionalise the surface of AZ31 magnesium alloy by applying a duplex MgF_(2)/chitosan coating,which improves its corrosion resistance and provides it with some antibacterial ***,the effect of three chitosan solutions with different concentrations on the growth of the bacteria Klebsiella pneumoniae in nutritive medium(TSB)was evaluated by absorbance kinetics experiments,where the chitosan solution at 2%(m/V)was selected for the coating *** coating application,the AZ31 substrate was pretreated with hydrofluoric acid for 48 hours in order to form a MgF_(2)conversion ***,the coating was applied to the pretreated substrate through the dry-casting *** of the alloy in each surface condition(bare,pretreated,and pretreated+coated with chitosan)were exposed to simulated body fluid(SBF)for 21 days at 37°C,with the solution renewed every 24 hours and the wastes *** surfaces were characterised by SEM-EDS,and XPS after the immersion tests,whereas the stored solutions were employed to measure the change in the Mg-ions *** impedance spectroscopy and potentiodynamic polarisation were performed in each surface condition to compare their corrosion resistance in *** antibacterial activity of the functionalised surfaces was evaluated by the plate counting method and compared with bare *** results were correlated and demonstrate that the modified surface of AZ31 achieved a higher corrosion resistance when it was exposed to SBF,as well as a reduction of the bacterial growth during in vitro tests.

关键词： AZ31 Chitosan coating Simulated body fluid Corrosion Antibacterial activity

The digital‘connected’earth:open technology for providing location-based services on degraded communication environments

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International Journal of Digital Earth 2018年第8期11卷 761-782页

作者： Ramón Piedrafita Rubén Béjar Rubén Blasco Alvaro Marco F.Javier Zarazaga-soria Aragón Aragón Institute of Engineering Research Universidad de ZaragozaZaragozaSpain

n the current world,it is easy to listen that everybody and everything is *** this connected world,the concept of location-based services has grown in order to provide digital services in everyplace and at every ***,this is not 100%true because the connection is not guaranteed for many people and in many *** are the Degraded Communications Environments(DCE),environments where the availability of high-speed communications is not guaranteed in at least the 75%of the *** paper works over the experience of a previous work in developing light protocols that do not need broadband for *** work provides an extension of these protocols for the inclusion of mobile devices as elements of the communication process and a set of libraries to allow the development of applications in *** work done has involved the development of two frameworks:an Android framework that makes the incorporation of Android devices easier and a server-based framework that provides the server side for the development of the referred applications.A use case that uses these two frameworks has been ***,all technology developed is available throw a public Git repository.

关键词： Location-based services degraded communications environments open technology

Grasp Planning and Visual Servoing for an Outdoors Aerial Dual Manipulator

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Engineering 2020年第1期6卷 77-88页

作者： Pablo Ramon-soria Begoña CArrue Anibal Ollero Robotics Visionand Control GroupSchool of EngineeringUniversity of SevilleSeville 41092Spain

This paper describes a system for grasping known objects with unmanned aerial vehicles (UAVs) provided with dual manipulators using an RGB-D camera. Aerial manipulation remains a very challenging task. This paper covers three principal aspects for this task: object detection and pose estimation, grasp planning, and in-flight grasp execution. First, an artificial neural network (ANN) is used to obtain clues regarding the object’s position. Next, an alignment algorithm is used to obtain the object’s sixdimensional (6D) pose, which is filtered with an extended Kalman filter. A three-dimensional (3D) model of the object is then used to estimate an arranged list of good grasps for the aerial manipulator. The results from the detection algorithm—that is, the object’s pose—are used to update the trajectories of the arms toward the object. If the target poses are not reachable due to the UAV’s oscillations, the algorithm switches to the next feasible grasp. This paper introduces the overall methodology, and provides the experimental results of both simulation and real experiments for each module, in addition to a video showing the results.

关键词： Aerial manipulation Grasp planning Visual servoing

Assessment of Mg(OH)_(2)/TiO_(2) coating in the Mg-Ca-Zn alloy for improved corrosion resistance and antibacterial performance

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Journal of Magnesium and Alloys 2023年第1期11卷 361-378页

作者： Leonardo Hernández Jesús Ramón-Sierra Montserrat soria-Castro Ángel Bacelis Geonel Rodríguez-Gattorno Elizabeth Ortiz-Vázquez Gloria Acosta Applied Physics Department Center for Research and Advanced Studies of the National Polytechnic Institute(CINVESTAV-IPN)Carr.Ant.a Progreso km.6C.P.97310MeridaYucatanMexico Tecnológico Nacional de México/Instituto Tecnológico de Mérida.Av.Tecnológico s/n Km.4.5 ant.Carr.Mérida-Progreso C.P.97118MéridaYucatánMéxico Facultad de Química Universidad Nacional Autónoma de México(UNAM)Av.Universidad 3000C.P.04510CoyoacánCDMXMéxico

The high activity of metallic magnesium and alloys limits its potential in biomedical applications;in recent years,extensive efforts have been devoted to modulating this *** this work,we present Mg(OH)_(2) and TiO_(2)barrier coatings to reduce the degradation of magnesium alloy(Mg-Ca-Zn)*** coatings were deposited by the anodization method and the spin-coating technique,*** anodized layer was coated with TiO_(2)generated from the hydrolysis of 3%weight of TTIP(Ti[OCH(CH_(3))_(2)]_(4),Titanium(IV)isopropoxide)in 2-Propanol deposited by the spin-coating *** the degradation in Ringer’s solution by electrochemical impedance spectroscopy and OCP revealed a 98%reduction in pittings in uncoated samples after 14 days of *** p H measurements revealed that the TiO_(2)coating reduced the alkalization of the physiological environment,keeping the pH at 6.0 *** vitro studies of two types of bacteria(*** and ***)exhibited zones of inhibition in the agar and activity bactericidal(kill time test).The mechanisms behind the improved degradation resistance and enhanced antibacterial activity are presented and discussed *** modification with Mg(OH)_(2)/TiO_(2)coatings is a promising strategy to control the biodegradation of magnesium implants for bone regeneration.

关键词： Magnesium alloy EIS Mg(OH)_(2) TiO_(2) Antibacterial coatings

A Cross Sectional Study on the Correlation between Waist Circumference and Fatty Liver on Ultrasonography among Non-Alcoholic Filipino Adults

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Open Journal of Endocrine and Metabolic Diseases 2023年第1期13卷 1-16页

作者： Arriza Kryssan S. Monjardin-soria Chong Hua Hospital Cebu City Philippines

Objectives: This study aimed to determine the correlation between waist circumference and fatty liver on ultrasonography among non-alcoholic Filipino adults. This will aid in detecting non-alcoholic fatty liver disease in its early course, hence improving our current therapeutic recommendations in preventing and managing the adverse health outcomes of NAFLD. Methods and Materials: A cross-sectional study with a total of 65 recruited participants. The data collected were age, sex, waist-circumference, co-morbidities with maintenance medications, history of alcohol intake with emphasis on the quantity and duration, and history of drug intake. Waist circumference was measured and recorded. The presence of NAFLD was determined through a review of the ultrasonography results of all subjects. The demographic profile and waist circumference of all subjects were described using descriptive statistics. The chi-square test was utilized to test the independence of the NAFLD and WC in the quartile. Pearson correlation was used to determine the linear relationship between the variables. Pearson correlation coefficient was statistically significant at p 0.05. Results: Among the subjects, 26 (42%) presented with fatty liver based on ultrasonography, 15 (58%) and 11 (42%), males and females, respectively. The mean waist circumference of 97.5 ± 12.43 was significantly related to the fatty liver with a p-value of 0.0001. Waist circumference showed a positive correlation with the frequency of fatty liver on ultrasonography with p-values of 0.000755 (r = 0.590083) and 3.04366E—05 (r = 0.659143523), in males and females, correspondingly. The overall correlation between waist circumference and fatty liver on ultrasonography is statistically significant with a p-value of 4.10503E—08 (r = 0.634737127). Conclusion: One measure used to assess central obesity is waist circumference. In addition, it can also be utilized to assess risk for NAFLD since they are strongly correlated as reported in

关键词： Non-Alcoholic Fatty Liver Waist Circumference NAFLD

Non-redundant Contribution of the Plastidial FAD8 ω-3 Desatumse to Glycerolipid Unsatumtion at Different Temperatures in Arabidopsis

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Molecular Plant 2015年第11期8卷 1599-1611页

作者： Angela Roman Maria L. Hernandez Angel soria-Garcia Sara Lopez-Gomollon Beatriz Lagunas Rafael Picorel Jose Manuel Martinez-Rivas Miguel Alfonso Estacion Experimental de Aula Dei (EEAD-CSIC) Avda. Montanana 1005 50059 Zaragoza Spain Instituto de la Grasa (IG-CSIC) Campus Universidad Pablo de Olavide Building 46 Ctra. Utrera kin 1 41013 Seville Spain

Plastidial ω-3 desaturase FAD7 is a major contributor to trienoic fatty acid biosynthesis in the leaves of Arabidopsis plants. However, the precise contribution of the other plastidial ω-3 desaturase, FAD8, is poorly understood. Fatty acid and lipid analysis of several ω-3 desaturase mutants, including two insertion lines of AtFAD7 and AtFAD8, showed that FAD8 partially compensated the disruption of the AtFAD7 gene at 22℃, indicating that FAD8 was active at this growth temperature, contrasting to previous observations that circumscribed the FAD8 activity at low temperatures. Our data revealed that FAD8 had a higher selectivity for 18：2 acyl-lipid substrates and a higher preference for lipids other than galactolipids, particularly phosphatidylglycerol, at any of the temperatures studied. Differences in the mechanism controlling AtFAD7 and AtFAD8 gene expression at different temperatures were also detected. Confocal microscopy and biochemical analysis of FAD8-YFP over-expressing lines confirmed the chloroplast envelope localization of FAD8. Co-localization experiments suggested that FAD8 and FAD7 might be located in close vicinity in the envelope membrane. FAD8-YFP over-expressing lines showed a specific increase in 18：3 fatty acids at 22℃. Together, these results indicate that the function of both plastidial ω-3 desaturases is coordinated in a non-redundant manner.

关键词： Arabidopsis thaliana glycerolipid fatty acid FAD7 FAD8 plastid

Effect of double-balloon enteroscopy on pancreas:An experimental porcine model

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World Journal of Gastroenterology 2012年第37期18卷 5181-5187页

作者： Rafael Latorre Federico soria Octavio López-Albors Ricardo Sarriá Francisco Sánchez-Margallo Pilar Esteban Fernando Carballo Enrique Pérez-Cuadrado Department of Anatomy and Comparative Pathology University of MurciaCampus de Espinardo Jesús Usón Minimally Invasive Surgery Center 10071 CáceresSpain Jesús Usón Minimally Invasive Surgery Center Digestive Service Morales Meseguer Hospital Digestive Service Virgen de la Arrixaca Hospital

AIM： To evaluate the effect of double-balloon enteros- copy （DBE） on pancreas histology and levels of pancre- atic enzymes. METHODS： Conventional upper gastrointestinal endos- copy was performed on five control pigs. Oral DBE was performed with an EN-450T5 enteroscope on 20 pigs. Two experimental groups （10 pigs each） were defined according to DBE duration： 90 rain for Group 1 and 140 min for Group 2. During oral insertion, the balloons were not inflated in the descending part of the duodenum to avoid the minor duodenal papilla. Serum amy- lase, lipase and C-reactive protein （CRP） levels were monitored before the procedure and repeated every 30 min until the exploration was finished, as well as 24 h and 7 d after. After the procedure and for a total of 7 d, the pigs were observed twice a day for signs of de- creased activity, irritability, vomiting or anorexia. Gross and microscopic examination of the pancreas was per- formed on day 7. RESULTS： All animals tolerated DBE without clini- cal manifestations of acute pancreatitis. Experimental groups had higher levels of enzymes than the control group at 24 h. Throughout the exploration, the amylase levels increased significantly above the baseline 24 h after DBE, although the increase was not statistically significant and did not reach 20% of the baseline. An increase in lipase and CRP was observed at 24 h after the procedure, although by day 7, all enzymatic lev- els had returned to baseline. No differences between Groups 1 and 2 were found for any enzyme and sam- pling site during and after the procedure. Similarly, no correlation between insertion depth and enzyme levels was observed. Direct in situ and post-removal inspec- tion of the pancreas did not show any evidence of fluid collection, abscesses or hemorrhage. Histological examination of the pancreas from Groups 1 and 2 re- vealed the existence of focal areas （0.14-0.26 mm2） of ischemic necrosis in 47.4% of the animals. In the pigs with damaged pancreas, the lef

关键词： Endoscopy Pancreatitis Double-balloon en-teroscopy Experimental study Pig model

Benzyl Amino Purine and Gibberellic Acid Coupled to Nitrogen-Limited Stress Induce Fatty Acids,Biomass Accumulation,and Gene Expression in Scenedesmus Obliquus

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Phyton-International Journal of Experimental Botany 2021年第2期90卷 515-531页

作者： Hans Christian Correa-Aguado Gloria Viviana Cerrillo-Rojas Alejandro Rocha-Uribe Ruth Elena soria-Guerra JoséFrancisco Morales-Domínguez Departamento de Química Centro de Ciencias BásicasUniversidad Autónoma de AguascalientesAguascalientes20131México Facultad de Ciencias Químicas Universidad Autónoma de San Luis PotosíSan Luis Potosí78210México Instituto Politécnico Nacional Unidad Profesional Interdisciplinaria de Ingeniería Campus ZacatecasBlvd.del Bote 202Cerro del Gato Ejido La EscondidaCol.Ciudad AdministrativaZacatecasZAC 98160Mexico

The need for renewable energy sources makes microalgae an essential feedstock for biofuels *** molecular aspects and the response to nitrogen(N)-limited conditions with a phytohormone stimulus in microalgae have been slightly *** this work,Scenedesmus obliquus was used as a study model to analyze the effect of benzyl amino purine(BAP)and gibberellic acid(GA)coupled to nitrogen limitation on cell growth,biomass and fatty *** selected 10^(-5)M BAP increased the biomass by 1.44-fold,and 10^(-6)M GA by *** total lipids also increased by 2.8 and 1.11-fold,*** 10^(-5)M BAP and 10^(-6)M GA addition to *** cultures at different initial nitrogen percentages(N-0,N-25,and N-50)showed a significant increase in cell growth and biomass productivity compared to the unstimulated *** N-0 and GA N-0 produced the highest lipid yields with 55%and 50%,*** lipid profile analysis revealed an increase,particularly in C18:1 and C16:0 fatty *** expression analysis showed an over-expression of acyl carrying protein(ACP),stearoyl-ACP desaturase(SAD),fatty acid acyl-ACP thioesterase(FATA),and diacylglycerol acyltransferase(DGAT)genes,which were mainly induced by nitrogen ***,BAP and GA produced a significant over-expression on these genes in the N-replete *** study shows that BAP and GA,coupled to N limitation stress,can be used to increase the biomass and lipid production in *** for sustainable biofuels.

关键词： Biodiesel gene expression lipids microalgae nitrogen deficiency phytohormones