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World Journal of Gastroenterology 2006年第24期12卷 3938-3943页

作者： EM López-Tomassetti Fernández h díaz luis A Martín Malagón I Arteaga González A Carrillo Pallarés department of Gastrointestinal Surgery University hospital of Canary Islands Ofra s/n. La Cuesta38320 La LagunaSanta Cruz de TenerifeSpain

Inflammatory myofibroblastic tumors （IMTs） or inflammatory pseudotumors （IPs） have been extensively discussed in the literature. They are usually found in the lung and upper respiratory tract. however, reporting of cases involving the biliopancreatic region has increased over recent years. Immunohistochemical study of these lesions limited to the pancreatic head or distal bile duct seems to be compatible with those observed in a new entity called autoimmune pancreatitis, but usually intense fibrotic reaction （zonation） predominates producing a mass. When this condition is limited to the pancreatic head, the common bile duct might be involved by the inflammatory process and jaundice may occur often resembling adenocarcinoma of the pancreas. We have previously reported a case of IMT arising from the bile duct associated with autoimmune pancreatitis which is an extremely rare entity. Four years after Kaush-Whipple resection, radiological examination on routine follow-up revealed a tumor mass, suggesting local recurrence. Ultrasound-guided FNA confirmed our suspicious diagnosis. This present case, as others, suggests that persistent follow-up is necessary in order to prevent irreversible liver damage at this specific location.

关键词： Inflammatory myofibroblastic tumor Inflammatory pseudotumor Local recurrence Pancreasresection Whipple procedure

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer M.Colón-Mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose M.Santiago Samuel E.Ocasio Rivera dina P.Bracho-Rincon luis h.Pagan Rivera Jorge d.Miranda department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain EAAT-1/GLAST EAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

Ni-based catalysts obtained from perovskites oxides for ethanol steam reforming

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燃料化学学报 2018年第11期46卷 1332-1341页

作者： Fabiola Nerina Agüero Jose Antonio Alonso Maria Teresa Fernández-díaz luis Eduardo Cadus Instituto de Investigaciones en Tecnología Química(INTEQUI) UNSL-CONICETAlmirante Brown 14555700 San LuisArgentina Instituto de Ciencia de Materiales de Madrid Consejo Superior de Investigaciones CientíficasCantoblanco28049 MadridSpain Institut Laue-Langevin B.P.156F-38042 Grenoble Cedex 9France

Perovskites as host structures of cations were used in order to generate in situ active and stable catalysts for ethanol steam reforming. For this purpose,La_(1-x)Mg_xAl_(1-y)Ni_yO_3(x = 0.1; y = 0,0.1,0.2,0.3) perovskites were synthetized by the citrate *** segregation is evident for a substitution level higher than 0. 2. The segregation of Ni as NiO generated species interacts with different metal-support after the reduction step. The y = 0.1 catalyst presents the highest h_2 yield value about 85% during reaction time,with low mean values of Ch_4 and CO selectivities of 3.4% and 11%,respectively and a low carbon formation. The better performance of y = 0.1 catalyst could be attributed to the minor proportion of segregated phases,thus a controlled expulsion of Ni is successfully reached.

关键词： perovskites catalyst design ethanol steam reforming

Black holes in asymptotic safety with higher derivatives:accretion and stability analysis

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Chinese Physics C 2021年第7期45卷 293-304页

作者： Fabian h.Zuluaga luis A.Sanchez Escuela de Fisica Universidad Nacional de ColombiaA.A.3840MedellinColombia

We review steady spherically symmetric accretion onto a renormalization group improved Schwarzschild space-time,which is a solution to an asymptotically safe theory(AS)containing high-derivative *** use a hamiltonian dynamical system approach for the analysis of the accretion of four types of isothermal test fluids:ultra-stiff fluid,ultra-relativistic fluid,radiation fluid,and sub-relativistic *** important outcome of our study is that,contrary to the claim in a recent work,there are physical solutions for the accretion of an ultra-relativistic fluid in AS,which include subsonic,supersonic,and transonic ***,we study quantum corrections to the known stability of the accretion in general relativity(GR).To this end,we use a perturbative procedure based on the continuity equation with the mass accretion rate being the perturbed *** classes of perturbations are studied:standing and traveling *** find that quantum gravity effects either enhance or diminish the stability of the accretion depending on the type of test fluid and the radial distance to the central object.

关键词： asymptotic safety black holes accretion stability

Risk-based method to secure power systems against cyberphysical faults with cascading impacts: a system protection scheme application

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Journal of Modern Power Systems and Clean Energy 2018年第5期6卷 930-943页

作者： Jose luis CALVO Simon h.TINdEMANS Goran STRBAC department of Electrical and Electronic Engineering Imperial College London department of Electrical Sustainable Energy Delft University of Technology

The utilization levels of the transmission network can be enhanced by the use of automated protection schemes that rapidly respond to disturbances. however,such corrective systems may suffer from malfunctions that have the potential to exacerbate the impact of the disturbance. This paper addresses the challenge of jointly optimizing the dispatch of generators and protection settings in this context. This requires a holistic assessment of the cyber(protection logic) and physical(network) systems,considering the failures in each part and their *** protection schemes are used as a prototypical example of such a system. An iterative optimization method is proposed that relies on power system response simulations in order to perform detailed impact assessments and compare candidate solutions. The candidate solutions are generated on the basis of a security-constrained dispatch that also secures the system against a set of cyber failure modes. A case study is developed for a generation rejection scheme on the IEEE reliability testsystem(RTS): candidate solutions are produced based on a mixed integer linear programming optimisation model, and loss-of-load costs are computed using a basic cascading outage algorithm. It is shown that the partial security approach is able to identify solutions that provide a good balance of operational costs and loss-of-load risks, both in a fixed dispatch and variable dispatch context.

关键词： Power system operations Cyber-physical systems Reliability System protection schemes Riskaware dispatch

Proposed Equation to Estimate the Length of a hydraulic Jump in a Rectangular Open Channel hydraulic with Variable Slope, and Its Comparison with Seven Theoretical Equations of Specialized Literature

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Journal of Water Resource and Protection 2019年第12期11卷 1481-1488页

作者： Martín Mundo-Molina José luis díaz Pérez Engineering Faculty Chiapas State University Chiapas Mexico

A hydraulic jump is a localized phenomenon that generates on an open hydraulic channel;however, its mathematical demonstration is not possible in the turbulent area of the phenomenon, especially in the area where the jump occurs and where its length is measured, so the data must be obtained with direct measurements in a laboratory and through empiric equations. This work presents the results of the generated hydraulic jumps and the measure of its length in a series of tests, where we input different flow rates in a transportable open channel hydraulic with a constant gate opening “a” and a slope of S = 0.0035, in the Engineering Faculty Research Centre of the Autonomous University of Chiapas. We also present the experimental method to generate a hydraulic jump, the measure of its length and a comparison with seven empirical equations, including the Sieñchi equation used in h-Canales, the most used software for hydraulic channels design in Latin America. The results show that the calculus of L with the proposed equation has a mean squared error (MSE) of 0.1337, a Bias of -0.0049, a model efficiency (ME) of 0.9991 and a determination coefficient (R2) of 0.9993 when compared with the experimental model. Meanwhile, the comparison of L calculated with the Sieñchi equation versus the experimental model resulted in a MSE of 0.1741, a bias of -0.0437, a ME of 0.9984 and a R2 of 0.9997. Both equations are highly recommended to estimate L in rectangular channels under the conditions presented in this paper, thus, the proposed equation can be applied if??y . Finally, it must be stated that we also proved that the Pavlosky equation is comparable in precision and accuracy concerning to proposed equation and Sieñchi equation.

关键词： hydraulic Jump Open Channel hydraulic hydraulics Experiments Length of the Stilling Basin

Sintering study of Ti6Al4V powders with different particle sizes and their mechanical properties

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1389-1401页

作者： Joséluis Cabezas-Villa JoséLemus-Ruiz didier Bouvard Omar Jiménez héctor Javier Vergara-hernández luis Olmos University Michoacana of San Nicolás of hidalgo IIMMMorelia 58060México University Grenoble Alpes CNRSSIMaPGrenoble 38000France University of Guadalajara Departamento de Ingeniería de ProyectosZapopan 45100México National Technological Institute of Mexico I.T.MoreliaMorelia 58120México University Michoacana of San Nicolás of hidalgo INICITMorelia 58060México

Ti6Al4V powders with three different particle size distributions(0–20, 20–45, and 45–75 μm) were used to evaluate the effect of the particle size distribution on the solid-state sintering and their mechanical properties. The sintering kinetics was determined by dilatometry at temperatures from 900 to 1260°C. The mechanical properties of the sintered samples were evaluated by microhardness and compression tests. The sintering kinetics indicated that the predominant mechanism depends on the relative density irrespective of the particle size used. The mechanical properties of the sintered samples are adversely affected by increasing pore volume fraction. The elastic Young's modulus and yield stress follow a power law function of the relative density. The fracture behavior after compression is linked to the neck size developed during sintering, exhibiting two different mechanisms of failure: interparticle neck breaking and intergranular cracking in samples with relative densities below and above of 90%, respectively. The main conclusion is that relative density is responsible for the kinetics, mechanical properties, and failure behavior of Ti6 Al4 V powders.

关键词： Ti6Al4V powders dilatometry microhardness sintering kinetics compression failure behavior

Approaches for handling high-dimensional cluster expansions of ionic systems

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npj Computational Materials 2022年第1期8卷 1254-1264页

作者： Julia h.Yang Tina Chen luis Barroso-Luque Zinab Jadidi Gerbrand Ceder department of Materials Science and Engineering BerkeleyCA94720USA Materials Sciences division Lawrence Berkeley National LaboratoryBerkeleyCA94720USA

disordered multicomponent systems attract great interest due to their engineering design flexibility and subsequent rich space of ***,detailed characterization of the structure and atomic correlations remains challenging and hinders full navigation of these complex spaces.A lattice cluster expansion is one tool to obtain configurational and energetic *** in theory a cluster expansion can be applied to any system of any dimensionality,the method has primarily been used in binary systems or ternary *** we apply cluster expansions in high-component ionic systems,setting up the largest cluster expansion ever attempted to our *** doing so,we address and discuss challenges specific to high-component ionic systems,namely charge state assignments,structural relaxations,and rank-deficient *** introduce practical procedures to make the fitting and analysis of complex systems tractable,providing guidance for future computational studies of disordered ionic systems.

关键词： properties cluster ionic

Getting started in mapping-by-sequencing

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Journal of Integrative Plant Biology 2015年第7期57卷 606-612页

作者： héctor Candela Rubén Casanova-Sáez José luis Micol Instituto de Bioingeniería Universidad Miguel Hernández department of Forest Genetics and Plant Physiology Umea Plant Science CenterSwedish University of Agricultural Sciences

Next-generation sequencing （NGS） technologies allow the cost-effective sequencing of whole genomes and have expanded the scope of genomics to novel applications, such as the genome-wide characterization of intraspecific polymorphisms and the rapid mapping and identification of point mutations. Next-generation sequencing platforms, such as the Illumina hiSeq2ooo platform, are now commercially available at affordable prices and routinely produce an enormous amount of sequence data, but their wide use is often hindered by a lack of knowledge on how to manipulateand process the information produced. In this review, we focus on the strategies that are available to geneticists who wish to incorporate these novel approaches into their research but who are not familiar with the necessary bioinformatic concepts and computational tools. In particular, we comprehensively summarize case studies where the use of NGS technologies has led to the identification of point mutations, a strategy that has been dubbed ＂mapping-by-sequencing＇, and review examples from plants and other model species such as Caenorhabditis elegans, Saccharomyces cerevisiae, and drosophila mela- nogaster. As these technologies are becoming cheaper and more powerful, their use is also expanding to allow mutation identification in species with larger genomes, such as many crop plants.

关键词： Mapping-by-sequencing massively parallel sequencing mutation identification ShOREmapping whole-genome re-sequencing

Fast magnitude determination using a single seismological station record implementing machine learning techniques

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Geodesy and Geodynamics 2018年第1期9卷 34-41页

作者： luis h.Ochoa luis F.Nino Carlos A.Vargas Universidad Nacional de Colombia Carrera 45 N°26-85 Edificio Manuel Ancizar-Of:330BogotaColombia

In this work a Support Vector Machine Regression（SVMR） algorithm is used to calculate local magnitude（MI） using only five seconds of signal after the P wave onset of one three component seismic station. This algorithm was trained with 863 records of historical earthquakes, where the input regression parameters were an exponential function of the waveform envelope estimated by least squares and the maximum value of the observed waveform for each component in a single station. Ten-fold cross validation was applied for a normalized polynomial kernel obtaining the mean absolute error for different exponents and complexity parameters. The local magnitude（MI） could be estimated with 0.19 units of mean absolute error. The proposed algorithm is easy to implement in hardware and may be used directly after the field seismological sensor to generate fast decisions at seismological control centers, increasing the possibility of having an effective reaction.

关键词： Earthquake early warning Support Vector Machine Regression Earthquake Rapid response Local magnitude Seismic event Seismology Bogota Colombia