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Retrieval of Elastic Green’s Tensor near a cylindrical Inhomogeneity from Vector correlations

communications in computational Physics 2008年第1期3卷 250-270页

作者： Juan AP´erez-ruiz Francisco Luzon Francisco J.Sanchez-Sesma Grupo de Geof´ısica Aplicada Departamento de F´ısica AplicadaUniversidad de Almer´ıaCa˜nada de San Urbano s/n04120-Almer´ıaSpain Departamento de Sismolog´ıa Instituto de IngenieriaUniversidad Nacional Aut´onoma de M´exicoCd.UniversitariaCircuito Escolar s/nCoyoac´an 04510M´exico D.F.Mexico.

Multiple scattering of elastic waves in realistic media makes that averagefield intensities or energy densities follow diffusive processes. In such regime the successiveP to S energy conversions by distributed random inhomogeneities give rise toequipartition which means that in the phase space the available elastic energy is distributedin averagewith equal amounts among the possible states of P and S waves. Insuch diffusive regime the P to S energy ratio equilibrates in an universal way independentof the particular details of the scattering. It has been demonstrated that averagingthe cross correlations at any two points of an elastic medium subjected to diffuse elasticwavefields leads to the emergence of the Green function, which is the wave fieldthat would be observed at one position if an impulsive load is applied at the other. Inthis work we study the problem of the retrieval of the 2D tensor elastodynamic Greenfunction in an infinite elastic space containing a circular cylinder inclusion. We illuminateisotropically the elastic spacewith plane waves. We assume the spectra for both Pand S waves uniform but such that the energy ratio ES/EP=(a/b)2, which is the onepredicted by equipartition theory in two-dimensions. We then show that the Fouriertransform of azimuthal average of the cross-correlation of motion between two pointswithin an elastic medium is proportional to the imaginary part of the exact Green tensorfunction between these points. The numerical results presented here point out thepossibility of detection and imaging of diffractors and resonant diffractors by crosscorrelation even in presence of attenuation exists.

关键词： Multiple scattering elastic waves elastic Green’s tensor

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Electromagnetic analysis and Ac losses of triaxial cables with multiple 2G-HTS layers per phase

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Superconductivity 2023年第1期5卷 46-54页

作者： M.clegg H.S.ruiz college of Science and Engineering&Space Park Leicester University RoadLeicester LE17RHUnited Kingdom

For an accurate estimation of the Ac losses of superconducting triaxial cables,in this paper we present a two‐dimensional model capable to provide a global assessment of multi‐layer triaxial cables,validated against the reported Ac‐losses measurements on single‐phase cables provided by the Russian Scientific and Research Institute of the cable Industry(VNIIKP).Four models are presented,the first being a single‐phase cable of 50 tapes and the others being three triaxial cables made of up to 135 coated conductors distributed in up to 9 layers.A systematic study is devised,where the number of layers per phase increases from 1 to 3,with at least 14 tapes distributed across each layer of the first(innermost)phase,15 in the secondary(middle)phase,and 16 in the third(outermost)phase,***,our results reveal that the simple strategy of considering an unbalanced distribution for the amplitudes of the applied current,can generally balance the magnetic field between the three phases even for the bilayer and trilayer cables,resulting in negligible magnetic leaks in all ***,our high‐resolution simulations allow to see for the first time how the transport and magnetization currents distribute across the thickness of all the superconducting tapes,from which we have found that the Ac‐losses of the 2nd phase is generally higher than at the other phases at low to moderate transport currents,I_(tr)c,being I_(c) the critical current of the corresponding ***,depending on whether the I_(c) of the Sc tapes at the 3rd phase layers is lower than the one at the 2nd phase,the layers at the third phase can exhibit a considerable increment on the Ac *** is result of the considered magneto angular anisotropy of the superconducting tapes,which lead to intriguing electromagnetic features that suggest a practical threshold for the applied transport current,being it 0:8I_(c).Likewise,the relative change in the Ac‐losses per adding layers,

关键词： Triaxial cables cOMSOL Electromagnetic profiles H‐formulation Ac losses

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PPIs are not associated with a lower incidence of portal-hypertension-related bleeding in cirrhosis

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World Journal of Gastroenterology 2010年第46期16卷 5869-5873页

作者： Mauricio Garcia-Saenz-de-Sicilia Francisco Sanchez-Avila Norberto c chavez-Tapia Gustavo Lopez-Arce Sandra Garcia-Osogobio Roberto ruiz-cordero Felix I Tellez-Avila Department of Gastroenterology Instituto Nacional de Ciencias Medicas y Nutrición Salvador ZubiranMexico CityMexico Medica Sur clinic and Fundation Endoscopy Department Instituto Nacional de Ciencias Medicas y Nutricion Salvador ZubiranMexico City14000Mexico

AIM:To determine if proton pump inhibitor use in cirrhotic patients with endoscopic findings of portal hypertension is associated with a lower frequency of gastrointestinal ***:Patients with cirrhosis and endoscopic findings related to portal hypertension,receiving or not receiving proton pump inhibitor (PPI) therapy,were included *** assigned patients to two groups:group 1 patients underwent PPI therapy and group 2 patients did not undergo PPI ***:One hundred and five patients with a median age of 58 (26-87) years were included,57 (54.3%) of which were *** varices were found in 82 (78%) patients,portal hypertensive gastropathy in 72 (68.6%) patients,and gastric varices in 15 (14.3%) *** therapy was used in 45.5% of patients (n=48).Seventeen (16.1%) patients presented with upper gastrointestinal bleeding;in 14/17 (82.3%) patients,bleeding was secondary to esophageal varices,and in 3/17 patients bleeding was attributed to portal hypertensive *** related to portal hypertension according to PPI therapy occurred in 18.7% (n=9) of group 1 and in 14% (n=8) of group 2 (odds ratio:0.83,95% confidence interval:0.5-1.3,P=0.51).cONcLUSION:Portal hypertension bleeding is not associated with PPI *** findings do not support the prescription of PPIs in patients with chronic liver disease with no currently accepted indication.

关键词： Drug prescription Liver cirrhosis Portal hypertension Proton pump inhibitors Upper gastrointestinal bleeding

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Sexual dimorphism in immune response： Testing the hypothesis in an insect species with two male morphs

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Insect Science 2013年第5期20卷 620-628页

作者： Gloria ruiz-Guzman Jorge canales-Lazcano Jesus Guillermo Jimenez-cortes Jorge contreras-Garduno centro de Investigacion Sobre Enfermedades Infecciosas Instituto Nacional de Salud Publica Av. Universidad No. 655 C. P. 62100 Cuernavaca Morelos Departamento de Biologia Divisi6n de Ciencias Naturales y Exactas Universidad de Guanajuato Guanajuato Departamento de Ecologia Evolufiva Instituto de Ecologia Universidad Nacional Autonoma de Mexico Apdo. Postal 70-275 04510 Mexico D. F. Mexico

It has been proposed that given that males should invest in sexual traits at the expense of their investment in immune response, females are better immunocompetent than males. Typically, this idea has been tested in monomorphic species, but rarely has been evaluated in polymorphic male species. We used Paraphlebia zoe, a damselfly with two male morphs： the black-winged morph （Black-W） develop black spots as sexual traits and the hyaline-winged morph （Hyaline-W） resembles a female in size and wings color. We predicted that Black-W should have a lower immune response than Hyaline-W, but that the latter males should not differ from females in this respect. Nitric oxide （NO） and phenoloxidase （PO） production, as well as hemolymph protein content, were used as immune markers. Body size （wing length） was used as an indicator of the male condition. The results show that, as we predicted, females and Hyaline-W had higher values of NO than Black-W, corresponding to differences in size. However, the opposite was found in relation to PO production. Females had the highest levels of hemolymph protein content, whereas no differences were found between Black-W and Hyaline-W. These results partially support the sexual selection hypothesis and are discussed in the context of the life history of this species. Black-W, Hyaline-W, and females could express the immune markers that are prioritized by their particular condition, and probably neither of them could express all immune markers in an elevated manner, as this would result in an excessive accumulation of free radicals.

关键词： immune response male morphs Paraphlebia zoe polymorphic species,territoriality trade-off

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Oxidative stress modulation in hepatitis c virus infected cells

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World Journal of Hepatology 2015年第29期7卷 2880-2889页

作者： Sonia A Lozano-Sepulveda Owen L Bryan-Marrugo carlos cordova-Fletes Maria c Gutierrez-ruiz Ana M Rivas-Estilla Department of Biochemistry and Molecular Medicine School of MedicineUniversidad Autonoma de Nuevo LeonMonterreyNuevo Leon 64460Mexico Department of Health Sciences Biological Sciences and Health DivisionSchool of Biological SciencesUniversidad Autonoma Metropolitana

Hepatitis c virus(HcV) replication is associated with the endoplasmic reticulum, where the virus can induce cellular stress. Oxidative cell damage plays an important role in HcV physiopathology. Oxidative stress is triggered when the concentration of oxygen species in the extracellular or intracellular environment exceeds antioxidant defenses. cells are protected and modulate oxidative stress through the interplay of intracellular antioxidant agents, mainly glutathione system(GSH) and thioredoxin; and antioxidant enzyme systems such as superoxide dismutase, catalase, GSH peroxidase, and heme oxygenase-1. Also, the use of natural and synthetic antioxidants(vitamin c and E, N-acetylcysteine, glycyrrhizin, polyenylphosphatidyl choline, mitoquinone, quercetin, S-adenosylmethionine and silymarin) has already shown promising results as co-adjuvants in HcV therapy. Despite all the available information, it is not known how different agents with antiviral activity can interfere with the modulation of the cell redox state induced by HcV and decrease viral replication. This review describes an evidence-based consensus on molecular mechanisms involved in HcV replication and their relationship with cell damage induced by oxidative stress generated by the virus itself and cell antiviral machinery. It also describes some molecules that modify the levels of oxidative stress in HcV-infected cells.

关键词： Hepatitis c virus Oxidative stress Reactiveoxygen species Vitamin E Antioxidants Glycyrrhizin S-adenosylmethionine N-acetylcysteine Silymarin

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The influence of elevation on soil properties and forest litter in the Siliceous Moncayo Massif,SW Europe

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Journal of Mountain Science 2016年第12期13卷 2155-2169页

作者： BADIA David ruiz Alberto GIRONA Antonio MARTI clara cASANOVA Jose IBARRA Paloma ZUFIAURRE Raquel Department of Agricultural and Environmental Sciences Technic School of Agricultural Engineering and Environmental SciencesUniversidad de Zaragoza Department of Geography and Land Management University of Zaragoza Department of Analytical chemistry Technic School of Agricultural Engineering and Environmental SciencesUniversity of Zaragoza

Understanding the effects of elevation and related factors(climate,vegetation) on the physical and chemical soil properties can help to predict changes in response to future climate or afforestation *** work aims to contribute to the knowledge of soil evolution and the classification of forest soils in relation to elevation in the montane stage,with special attention to podzolization and humus *** northern flank of the Moncayo Massif(Iberian Range,SW Europe) provides a unique opportunity to study a forest soils catena within a consistent quartzitic parent material over a relatively steep elevation *** increasing elevation,pH,base saturation,exchangeable potassium,and fine silt-sized particles decrease significantly,while organic matter,the c/N ratio,soil aggregate stability,water repellency and coarse sand-sized particles increase *** soil profiles shared a set of properties in all horizons:loamy-skeletal particle-size,extreme acidity(pH-H_2Ocesses in the catena include topsoil organic matter accumulation and even podzolization,which increases with *** the upper to lower landscape positions of wooded montane stage of the Moncayo Massif,mull-moder-mor humus and an Umbrisolcambisol-Podzol soil unit sequences were found.

关键词： Montane stage Forest soils catena Humus forms Podzolization Siliceous Moncayo Massif

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In vivo optical quality of posterior-chamber phakic implantable collamer lenses with a central port

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Eye and Vision 2021年第5期8卷 295-302页

作者： Robert Montés-Micó Francisco Pastor-Pascual Enrique Artiaga-Elordi Ramón ruiz-Mesa Pedro Tañá-Rivero Optics and Optometry&Vision Sciences Department University of Valenciac/o Dr Moliner 5046100 ValenciaSpain Oftalvist clinic ValenciaSpain

Background:The aim of this review is to summarize the optical quality results in patients following the implantation of the V4c implantable collamer lens with a central port(IcL,STAAR Surgical Inc.).Main text:A literature search in several databases was carried out to identify those publications,both prospective,retrospective and/or comparative with other refractive surgery procedures,reporting optical outcomes of patients who were implanted with the V4c IcL model.A total of 17 clinical studies published between 2012 and 2021 were included in this review.A detailed analysis of the available data was performed including number of eyes,follow-up and preoperative spherical ***,the review focused on several optical parameters including higher-order aberrations(HOAs),modulation transfer function(MTF)cut-off frequency and Strehl *** review encompassed a total of 817 eyes measured using different optical devices based on Hartmann-Shack,retinal image quality measurement and ray-tracing technologies at different ***:The outcomes found in this review lead us to conclude that the IcL V4c model provides good optical quality,by means of different metrics,when implanted.

关键词： Implantable collamer lens Phakic Optical quality Higher order aberrations Modulation transfer function

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Microstructural Development and Mechanical Properties of PM Ti-45Al-2Nb-2Mn-0.8 vol.%TiB_2 Processed by Field Assisted Hot Pressing

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Journal of Materials Science & Technology 2014年第11期30卷 1145-1154页

作者： R.Munoz-Moreno E.M.ruiz-Navas B.Srinivasarao J.M.Torralba Department of Materials Science and Engineering Universidad Carlos Ⅲ de MadridAvda.Universidad 3028911 LeganésMadridSpain IMDEA Materials Institute C/Eric Kandel 228906 GetafeMadridSpain

A γ-TiAI intermetallic alloy, Ti-45Al-2Nb-2Mn （at.%）-0.8 vol.%TiB2, has been processed from gas atomized praalloyed powder by field assisted hot pressing （FAHP）. An initial analysis of the prealloyed powder helped on the understanding of the intermetallic sintering behavior. Atomized powder consisted of α metastable phase that transformed into α2＋γ equilibrium phases by thermal treating. Different powder particle microstructures were found, which influence the microstructure development of the FAHP T-TiAI material depending on the sintering temperature. Duplex, nearly lamellar and fully lamellar microstructures were obtained at the sintaring temperatures above 1000 ℃. Lower consolidation temperatures, below 1000 ℃, led to the formation of an AI rich phase at powder particle boundaries, which is deleterious to the mechanical properties. High compressive yield strength of 1050 MPa was observed in samples with FAHP duplex microstructures at room temperature. Whereas nearly lamellar and fully lamellar microstructures showed yield strength values of 655 and 626 MPa at room temperature and 440 and 425 MPa at 750 ℃, respectively, which are superior in comparison to similar alloys processed by other techniques. These excellent properties can be explained due to the different volume fractions of the α2 and γ phases and the refinement of the PM microstructures.

关键词： Titanium aluminides Powder metallurgy Microstructure Mechanical properties Field assisted sintering

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One-year survival in recipients older than 50 bridged to heart transplant with Impella 5.5 via axillary approach

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Journal of Geriatric cardiology 2023年第5期20卷 319-329页

作者： Smit Paghdar Smruti Desai Ji-Min Jang Jose ruiz Sharan Malkani Parag Patel Daniel S Yip Juan c Leoni Jose Nativi Basar Sareyyupoglu Kevin Landolfo Si Pham Rohan M Goswami Division of Heart Failure and Transplant Mayo Clinic in FloridaUSA Department of cardiothoracic Surgery Mayo Clinic in FloridaUSA

BAcKGROUND Optimizing patients with advanced heart failure before orthotopic heart transplantation(OHT), especially in patients greater than 50 years old, is imperative to achieving successful post-transplant outcomes. complications are well-described for patients bridged to transplant(BTT) with durable left ventricular assist device(LVAD) support. Given the lack of data available in older recipients after the recent increase in mechanical support use, we felt it crucial to report our center’s one-year outcomes in older recipients after heart transplantation with percutaneously placed Impella 5.5 as a *** Forty-nine OHT patients were supported with the Impella 5.5 intended as a bridge between December 2019 and October 2022 at Mayo clinic in Florida. Data were extracted from the electronic health record at baseline and during their transplant episode of care after Institutional Review Boards approval as exempt for retrospective data *** Thirty-eight patients aged 50 or older were supported with Impella 5.5 as BTT. Ten patients underwent heart and kidney transplantation within this cohort. The median age at OHT was 63(58–68) years, with 32 male(84%) and six female patients(16%). Etiology was divided into ischemic(63%) and non-ischemic cardiomyopathy(37%). The baseline median ejection fraction was 19%(15–24). Most patients were in blood group O(60%), and 50% were diabetic. The average duration of support was 27 days(range 6–94). The median duration of follow-up is 488 days(185–693). For patients that have reached the 1-year follow-up timeframe(22 of 38, 58%), the 1-year post-transplant survival is 95%.cONcLUSION Our single-center data provides awareness for using the Impella 5.5 percutaneously placed axillary support device in older heart failure patients in cardiogenic shock as a bridge to transplantation. One-year survival outcomes after heart transplantation are excellent despite the older recipient’s age and prolonged pre-transplant support.

关键词： One approval transplant

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Biotinylated polyurethane-urea nanoparticles for targeted theranostics in human hepatocellular carcinoma

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Nano Research 2015年第5期8卷 1729-1745页

作者： Genoveva MorraI-ruiz Pedro Melgar-Lesmes Andrea Lopez-Vicente conxita Solans Maria Jose Garcia-celma Department of Pharmacy and Pharmaceutical Technology Faculty of Pharmacy University of Barcelona Av Joan XXIII s/n 08028 Barcelona Spain Institute of Advanced chemistry of catalonia (IQAc) CS/C Jordi Girona 18-26 08034 Barcelona Spain Networking Research center on Bioengineering Biomaterials and Nanomedicine CIBER-BBN Spain

Over the past years, significant efforts have been devoted to explore novel drug delivery and detection strategies for simultaneous therapy and diagnostics. The development of biotinylated polyurethane-urea nanoparticles as theranostic nanocarriers for targeted drug and plasmid delivery, for fluorescence detection of human hepatocellular carcinoma cells, is described herein. These targeted nanoparticles are specifically designed to incorporate biotin into the polymeric matrix, since many tumor types overexpress receptors for biotin as a mechanism to boost uncontrolled cell growth. The obtained nanoparticles were spherical, exhibited an average diameter ranging 110-145 nm, and showed no cytotoxicity in healthy endothelial cells. Biotinylated nanoparticles are selectively incorporated into the perinuclear and nuclear area of the human hepatocellular carcinoma cell line, HepG2, in division, but not into growing, healthy, human endothelial cells. Indeed, the simultaneous incorporation of the anticancer drugs, phenoxodiol or sunitinib, together with plasmid DNA encoding green fluorescent protein, into these nanoparticles allows a targeted pharmacological antitumor effect and furthermore, selective transfection of a reporter gene, to detect these cancer cells. The combined targeted therapy and detection strategy described here could be exploited for liver cancer therapy and diagnostics, with a moderate safety profile, and may also be a potential tool for other types of cancer.

关键词： cancer therapy DNA nanoparticles polyurethane theranostics

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