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World Journal of Transplantation 2024年第1期14卷 1-8页

作者： Cristian Lindner Raúl Riquelme Rodrigo San Martín Frank Quezada jorge Valenzuela Juan P Maureira Martín Einersen Department of Radiology Faculty of MedicineUniversity of ConcepciónConcepción 4030000Chile Department of Radiology Hospital Clínico Regional Guillermo Grant BenaventeConcepción 4030000Chile Department of Statistics Catholic University of MauleTalca 3460000Chile Neurovascular Unit Department of RadiologyHospital Clínico Regional Guillermo Grant BenaventeConcepción 4030000Chile

Hepatic artery thrombosis(HAT)is a devastating vascular complication following liver transplantation,requiring prompt diagnosis and rapid revascularization treatment to prevent graft *** present,imaging modalities such as ultrasound,computed tomography,and magnetic resonance play crucial roles in diagnosing *** imaging techniques have improved sensitivity and specificity for HAT diagnosis,they have limitations that hinder the timely diagnosis of this *** this sense,the emergence of artificial intelligence(AI)presents a transformative opportunity to address these diagnostic *** development of machine learning algorithms and deep neural networks has demonstrated the potential to enhance the precision diagnosis of liver transplant complications,enabling quicker and more accurate detection of *** article examines the current landscape of imaging diagnostic techniques for HAT and explores the emerging role of AI in addressing future challenges in the diagnosis of HAT after liver transplant.

关键词： Liver transplantation Postoperative complications Hepatic artery Thrombosis Radiology Artificial intelligence

A General Analytic Approximation Technique for the Modified Bessel Functions with Fractional Order Iv (x), Applied to I1/6(x) and I1/7(x)

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Advances in Pure Mathematics 2024年第9期14卷 768-777页

作者： jorge Olivares Pablo Martín Maria T. Veliz Departamento de Matemticas Universidad de Antofagasta Antofagasta Chile Departamento de Fsica Universidad de Antofagasta Antofagasta Chile

A general technique to obtain simple analytic approximations for the first kind of modified Bessel functions. The general procedure is shown, and the parameter determination is explained through the applications to this particular case I1/6(x)and I1/7(x). In this way, it shows how to apply the technique to any particular orderν, in order to obtain an approximation valid for any positive value of the variable x. In the present method power series and asymptotic expansion are simultaneously used. The technique is an extension of the multipoint quasirational approximation method, MPQA. The main idea is to look for a bridge function between the power and asymptotic expansion of the I1/6(x), and similar procedure for I1/7(x). To perform this, rational functions are combined with hyperbolic ones and fractional powers. The number of parameters to be determined for each case is four. The maximum relative errors are 0.0049 for ν=1/6, and 0.0047 for ν=7. However, these relative errors decrease outside of the small region of the variables, wherein the maximum relative errors are reached. There is a clear advantage of this procedure compared with any other ones.

关键词： Bessel Functions Power Series Asymptotic Expansion MPQA Technique

Kinetics of the H＋-ATPase from Dry and 5-Hours- Imbibed Maize Embryos in Its Native, Solubilized, and Reconstituted Forms

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Molecular Plant 2011年第3期4卷 505-515页

作者： Sobeida Sanchez-Nieto Consuelo Enriquez-Arredondo Fernando Guzmbn-Chavez Rolando hern&ndez-Munoz jorge Ramirez Marina Gavilanes-Ruiz Departamento de Bioquimica Facultad de Quimica Conjunto E. Universidad Nacional Autonoma de Mexico Cd Universitaria 04360 Mexico DF Mexico Instituto de Fisiologfa Celular Universidad Nacional Autonoma de Mexico Cd Universitaria 04360 Mexico DF Mexico

Membranes undergo recovery upon rehydration in seed germination. Previous work has described that the plasma membrane H＋-ATPase from maize embryos adopts two different forms at 0 and 5 h of imbibition. We investigated how the kinetics of these two forms could be affected by alterations in the plasma membrane （PM）. In comparison to the O-h, PMs from the 5-h imbibed embryos showed changes in glycerophospholipid composition, decrease in leakage, and increase in fluidity. Kinetics of the PM H^-ATPase from 0 and 5-h imbibed embryos showed negative cooperativity, With the removal of the membrane environment, the activity of the enzymes shifted to a more complex kinetics, displaying two enzyme components. Lipid reconstitution produced one component with positive cooperativity. In all cases, enzymes from 0 and 5-h imbibed embryos presented similar kinetics with some quantitative differences. These results indicate that the two enzyme forms have the potential ability to respond to changes in the membrane enyiror^rpent, but the fact that they do not show differences in the native membranes at 0 or 5 h implies that modifications in the membrane are not drastic enough to alter their kinetics, or that they are able to preserve their boundary lipids or associated proteins and thus retain the same kinetic behavior.

关键词： ATPase activity H^-ATPase maize germination plasma membrane H+-ATPase plasma membrane Zea mays.

Assessing above-ground biomass-functional diversity relationships in temperate forests in northern Mexico

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Forest Ecosystems 2021年第1期8卷 95-108页

作者： Benedicto Vargas-Larreta jorge Omar López-Martínez Edgar J.González JoséJavier Corral-Rivas Francisco Javier hernández Tecnológico Nacional de México/Instituto Tecnológico de El Salto 34942 El SaltoDurangoMexico Cátedras CONACYT1582Av.Insurgentes SurCiudad de MéxicoMexico El Colegio de la Frontera Sur 77014ChetumalQuintana RooMexico Departamento de Ecología y Recursos Naturales Facultad de CienciasUniversidad Nacional Autónoma de MéxicoCiudad de MéxicoMexico Facultad de Ciencias Forestales Universidad Juárez del Estado de DurangoRío Papaloapan y Blvd.Durango s/nCol.Valle del Sur34120 DurangoMexico

Background:Studies on the relationship between biodiversity and ecosystem productivity have suggested that species richness and functional diversity are the main drivers of ecosystem *** patterns on this relationship have been found,including positive,unimodal,negative,and neutral trends,keeping the issue *** this study,taxonomic diversity and functional diversity as drivers of above-ground biomass(AGB)were compared,and the mechanisms that influence biomass production were investigated by testing the complementarity and the mass-ratio ***:Using data from 414 permanent sample plots,covering 23%of temperate forest in the Sierra Madre Oriental(México),we estimated the above-gound biomass(AGB),taxonomic and functional diversity indices,as well as community weighted mean values(CWM)for three functional traits(maximum height,leaf size and wood density)for trees≥7.5 cm DBH,in managed and unmanaged *** compare taxonomic diversity differences between managed and unmanaged stands we carried out a rarefaction ***,we evaluated the relationship between AGB and taxonomic and functional diversity metrics,as well as CWM traits throught spatial autoregressive ***:We found a hump-shaped relationship between AGB and species richness in managed and unmanaged *** of maximum height was the most important predictor of AGB in both stands,which suggested that the mechanism underlaying the AGB-diversity relationship is the dominance of some highly productive species,supporting the mass-ratio ***-ground biomass was significantly correlated with three of the five functional diversity metrics,CWM maximum height and species *** results show the importance of taking into account spatial autocorrelation in the construction of predictive models to avoid spurious patterns in the AGBdiversity ***:Species richness,maximum height,functional richness,functional dispersion and Rao

关键词： Taxonomic diversity Functional diversity Complementarity hypothesis Mass-ratio hypothesis

Vertical Displacement Measurement in a Slow-Moving Sinkhole Using BOTDA

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Photonic Sensors 2024年第1期14卷 23-39页

作者： Pascual SEVILLANO Javier PRECIADO-GARBAYO jorge SEVIL Francisco GUTIERREZ Juan JMARTiNEZ Sonia MARTiN-LOPEZ Miguel GONZALEZ-HERRAEZ Aragon Institute of Engineering Research(I3A) Universidad de ZaragozaZaragoza 50018Spain Electronic Enginering and Communicaton Dpartment EINAUniversidad de ZaragzaZaragza 50018Spain Aragon Photonics Labs. Zaragoza 50009Spain Department of Earth Sciences Universidad de ZaragozaZaragoza 50009Spain Department of Electronics Escuela Politecnica SuperiorUniversidad de AlcalaMadrid 28805Spain

The effectiveness of monitoring and early-warning systems for ground deformation phenomena,such as sinkholes,depends on their ability to accurately resolve the ongoing ground displacement and detect the subtle deformation preceding catastrophic *** sinkholes with a slow subsidence rate and diffuse edges pose a significant challenge for subsidence monitoring due to the low deformation rates and limited lateral strain *** this work,we satisfactorily illustrate the practicality of the Brillouin optical time domain analysis(BOTDA)to measure the spatial-temporal patterns of the vertical displacement in such challenging slow-moving sagging *** assess the performance of the approach,we compare the strain recorded by the distributed optical fiber sensor with the vertical displacement measured by high-precision *** results show a good spatial correlation with the ability to identify the maximum subsidence *** is also a good temporal correlation with the detection of an acceleration phase in the subsidence associated with a flood event.

关键词： Distributed fiber optic sensing(DFOS) vertical displacement measurement slow subsidence rate sinkhole hazard early-warning system

Role of platelets and breast cancer stem cells in metastasis

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World Journal of Stem Cells 2020年第11期12卷 1237-1254页

作者： Gretel Mendoza-Almanza Luis Burciaga-hernandez Vilma maldonado jorge Melendez-Zajgla jorge Olmos CONACYT Universidad Autónoma de Zacatecas.Zacatecas 98060Mexico Maestría en Ciencias Biomédicas Universidad Autónoma de ZacatecasZacatecas 98160Mexico Laboratorio de Epigenética Instituto Nacional de Medicina GenómicaCiudad de México 14610Mexico Génómica funcional del cáncer Instituto Nacional de Medicina GenómicaCiudad de México 14610Mexico Biotecnología Marina Centro de Investigación Científica y de Estudios Superiores de EnsenadaEnsenada 22860Mexico

The high mortality rate of breast cancer is mainly caused by the metastatic ability of cancer cells,resistance to chemotherapy and radiotherapy,and tumor regression *** recent years,it has been shown that the presence of breast cancer stem cells is closely associated with the migration and metastatic ability of cancer cells,as well as with their resistance to chemotherapy and *** tumor microenvironment is one of the main molecular factors involved in cancer and metastatic processes development,in this sense it is interesting to study the role of platelets,one of the main communicator cells in the human body which are activated by the signals they receive from the microenvironment and can generate more than one *** can ingest and release RNA,proteins,cytokines and growth *** the platelets interact with the tumor microenvironment,they are called"tumor-educated platelets."Tumor-educated platelets transport material from the tumor microenvironment to sites adjacent to the tumor,thus helping to create microenvironments conducive for the development of primary and metastatic *** has been observed that the clone capable of carrying out the metastatic process is a cancer cell with stem cell *** stem cells go through a series of processes,including epithelial-mesenchymal transition,intravasation into blood vessels,movement through blood vessels,extravasation at the site of the establishment of a metastatic focus,and site ***-educated platelets support all these processes.

关键词： Breast cancer stem cells Platelets Metastasis Tumor microenvironment Epithelial-mesenchymal transition

Factors that influence outcome in non-invasive and invasive treatment in polycystic liver disease patients

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World Journal of Gastroenterology 2008年第20期14卷 3195-3200页

作者： Josué Barahona-Garrido Jesús Camacho-Escobedo Eduardo Cerda-Contreras jorge hernández-Calleros Jesús K Yamamoto-Furusho Aldo Torre Misael Uribe Department of Gastroenterology National Institute of Health Sciences and Nutrition "Salvador Zubirán" Mexico City 14000 Mexico

AIM: To evaluate the factors that influence outcome of both non-invasive and invasive treatment of polycystic liver disease. METHODS: Analysis of clinical files of patients with complete follow-up from July 1986 to June 2006. RESULTS: Forty-one patients (male, 7; female, 34), 47.8 ± 11.9 years age, and 5.7 ± 6.7 years follow-up, were studied. Alkaline phosphatase (AP) elevation (15% of patients) was associated with the requirement of invasive treatment (IT, P = 0.005). IT rate was higher in symptomatic than non-symptomatic patients (65.4% vs 14.3%, P = 0.002), and in women taking hormonal replacement therapy (HRT) (P = 0.001). Cysts complications (CC) were more frequent (22%) in the symptomatic patients group (P = 0.023). Patients with body mass index (BMI) > 25 (59%) had a trend to complications after IT (P = 0.075). Abdominal pain was the most common symptom (56%) and indication for IT (78%). Nineteen patients (46%) required a first IT: 12 open fenestration (OF), 4 laparoscopic fenestration (LF) and 3 fenestration with hepatic resection (FHR). Three required a second IT, and one required a third procedure. Complications due to first IT were found in 32% (OF 16.7%, LF 25%, FHR 66.7%), and in thesecond IT in 66.7% (OF 100%). Follow-up mortality rate was 0. CONCLUSION: Presence of symptoms, elevated AP, and CC are associated with IT requirement. HRT is associated with presence of symptoms and IT requirement. Patients with BMI > 25 have a trend be susceptible to IT complications. The proportions of complications are higher in FHR and second IT groups. RS is more frequent after OF.

关键词： Hepatic cysts Open fenestration Laparoscopic fenestration Hepatic resection Recurrenceof symptoms Hormonal replacement therapy

Use of δ^(18)O, δ^(13)C and NO_(3)^(-) to identify hydrogeochemical processes related to contamination in an aquifer located in central Mexico

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Acta Geochimica 2022年第3期41卷 367-392页

作者： JoséIván Morales-Arredondo María Aurora Armienta hernández Fátima Juárez-Aparicio jorge Federico Landa-Arreguín Itzamna Zaknite Flores-Ocampo Natural Resources Department Institute of GeophysicsNational Autonomous University of MexicoCiudad Universitaria No.3000Col.Copilco UniversidadCoyoacan Delegation04360 MexicoCDMXMexico Earth Sciences Postgraduate Program University National Autonomous of MexicoUniversity City No.3000Col.Copilco UniversityCoyoacán Delegation04510 MexicoCDMXMexico

In this work,an isotopic analysis of δ^(18)O,δ^(13)C,and NO_(3)^(-) concentrations was carried out to identify the origin and the processes related to the contamination of an aquifer located in the state of Guanajuato,*** research identified the possible sources of δ^(13)C in *** groundwater flow,CO_(2) participates in different hydrogeochemical reactions in which the dissolution of carbonates or biochemical processes related to biodegradation stand *** data of δ^(13)C,δ^(18)O,and the hydrogeochemical behavior of NO_(3)^(-) and HCO_(3)^(-) in water,in addition to isotopic data and the chemical composition of limestones in the study area,were determined to establish the isotopic signature and the processes undergone by the *** isotopic signature of rock and water samples indicated that metamorphic limestones contributed with carbon dioxide to deep groundwater,while in the upper aquifer,bacterial metabolic reactions during nitrification–denitrification could modify the isotopic signature of δ^(13)C in some wells,although atmospheric contribution also plays a *** modification of the carbon isotopic component is related to the precipitation of calcite in specific regions of the study area,input of atmospheric CO_(2),and soil(*** possible participation of C4-type plants in the assimilation-release of carbon).This process is not confirmed or completely ruled out in this study since agriculture is excessively developed throughout the *** joint interpretation of isotopic values and the hydrogeochemical behavior of major and conservative elements help in identifying possible pollution processes in which different carbon sources are related.

关键词： ^(18)O and^(13)C isotopes Groundwater pollution Nitrate Limestone

HVOF-sprayed HAp/S53P4 BG composite coatings on an AZ31 alloy for potential applications in temporary implants

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Journal of Magnesium and Alloys 2024年第1期12卷 345-360页

作者： Carlos A.Poblano-Salas John Henao Astrid L.Giraldo-Betancur Paola Forero-Sossa Diego German Espinosa-Arbelaez jorge A.González-Sánchez Luis R.Dzib-Pérez Susana T.Estrada-Moo Idelfonso E.Pech-Pech CIATEQ A.C. Av.Manantiales 23-AParque Industrial Bernardo QuintanaEl MarquésQuerétaro 76246Mexico CONAHCYT-CIATEQ A.C. Av.Manantiales 23-AParque Industrial Bernardo QuintanaEl MarquésQuerétaro 76246Mexico CONAHCYT-Cinvestav Libramiento Norponiente#2000.Fraccionamiento Real de JuriquillaQuerétaro 76230Mexico Universidad Tecnológica de Querétaro Av.Pie de la Cuesta N°2501Querétaro 76148Mexico CIDESI Av.Playa Pie de la Cuesta No 702Col.San PabloQuerétaro 76125Mexico Center for Corrosion Research Autonomous University of CampecheAv.Héroe de Nacozari No.480P.C.24070San Francisco de CampecheCam.Mexico

Bioactive thermal spray coatings produced via high-velocity oxygen fuel spray(HVOF)from hydroxyapatite(HAp)and bioactive glasses(BG)have the potential to be employed on temporary implants due to the ability of both HAp and BG to dissolve and promote osseointegration,considering that both phases have different reaction and dissolution rates under in-vitro *** the present work,75%***-25%wt.S53P4 bioactive glass powders were HVOF-sprayed to obtain HAp/S53P4 BG composite coatings on a bioresorbable AZ31 *** study is focused on exploring the effect of the stand-off distance and fuel/oxygen ratio variation as HVOF parameters to obtain stable structural coatings and to establish their effect on the phases and microstructure produced in those *** characterization techniques,such as scanning electron microscopy,X-ray diffraction,and Fourier transform infrared spectroscopy,were employed to characterize relevant structural and microstructural properties of the composite *** results showed that thermal gradients during coating deposition must be managed to avoid delamination due to the high temperature achieved(max 550℃)and the differences in coefficients of thermal *** was also found that both spraying distance and oxygen/fuel ratio allowed to keep the hydroxyapatite as the main phase in the *** addition,in-vitro electrochemical studies were performed on the obtained HAp/S53P4 BG composite coatings and compared against the uncoated AZ31 *** results showed a significant decrease in hydrogen evolution(at least 98%)when the bioactive coating was applied on the Mg alloy during evaluation in simulated body fluid(SBF).

关键词： Coatings Composites Thermal spray Temporary implants Hydrogen evolution

Cold and Fertile: Cryopreservation as an Innovative Tool in Addressing Challenges in Teratozoospermia

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Journal of Biosciences and Medicines 2024年第2期12卷 274-281页

作者： Víctor Manuel Soto-Márquez jorge Mulia-Rodríguez Daniel Osorio-González Molecular Biophysics Laboratory Faculty of Sciences Autonomous University of State of Mexico Toluca Mexico

Teratozoospermia is an infertility issue that affects a significant number of couples of reproductive age. One of the potential causes contributing to the global decline in seminal quality includes factors such as diet, alcohol and tobacco consumption, high levels of stress, and environmental influences. This underscores the need to preserve the fertility of these patients through cryopreservation techniques. In this review, we explore the latest methods for freezing seminal samples, highlighting their advancements and advantages in addressing the challenge of perpetuating animal species, particularly in the context of human infertility.

关键词： Cryopreservation Teratozoospermia Infertility