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Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasoundelastography

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World Journal of Gastroenterology 2020年第34期26卷 5169-5180页

作者： Elymir S Galvis-García Sergio Sobrino-Cossío Arturo Reding-Bernal yesica contreras-marín Karina Solórzano-Acevedo Patricia González-Zavala Rosa M Quispe-Siccha Unidad de Endoscopía Gastrointestinal Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Unidad de Endoscopia y Fisiología Digestiva HospitalÁngeles del PedregalMexico 10700Mexico Dirección de Investigación Hospital General de México“Dr.Eduardo Liceaga”Mexico 06720Mexico Unidad Profesional Interdisciplinaria de Biotecnología and Unidad de Investigación y Desarrollo Tecnológico Instituto Politécnico Nacional and Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Instituto de Investigaciones en Materiales and Unidad de Investigación y Desarrollo Tecnológico Universidad Nacional Autónoma de México and Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico Unidad de Investigación y Desarrollo Tecnológico Hospital General de México"Dr.Eduardo Liceaga"Mexico 06720Mexico

BACKGROUnD Endoscopic ultrasound(EUS)and endoscopic ultrasound elastography(EUS-E)simulation lessens the learning curve;however,models lack realism,diminishing *** To standardize the mechanical properties of polyvinyl alcohol(PVA)hydrogel for simulating organs and digestive *** PVA hydrogel(Sigma Aldrich,degree of hydrolysis 99%)for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México“*** Liceaga”,Mexico *** evaluated physical,contrast,elasticity and deformation coefficient characteristics in lesions,applying Kappa’s concordance and satisfaction questionnaire(Likert 4-points).RESULTS PVA hydrogel showed stable mechanical *** depended on molecular weight(MW)and concentration(C).PVA bblocks with the greatest density showed lowest tensile strength(r=-0.8,P=0.01).Lesions were EUSgraphically *** and heterogeneous examples were created from PVA blocks or PVA phantoms,exceeding(MW2=146000-186000,C9=15%and C10=20%)with a density under(MW1=85000-124000,C1=7%and C2=9%).We calculated elasticity and deformation parameters of solid(blue)areas,contrasting with the norm(Kappa=0.8;high degree of satisfaction).COnCLUSIOn PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E,facilitating practice and reducing *** amplified skills,while reducing the learning curve.

关键词： Endoscopic ultrasound simulators in endoscopy Polyvinyl alcohol Endoscopic ultrasound Endoscopic ultrasound elastography Strain Elasticity

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Sudden openings and gradual closures in canopy cover modulate acclimation,survival,and growth of a shade-tolerant rainforest tree species

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Journal of Forestry Research 2024年第5期35卷 78-90页

作者： Ana Paula Moretti Flavia yesica Olguin Juan marcelo Gauna Corina Graciano InFIVE(COnICET-Universidad nacional de La Plata) Diagonal 113 N°4951900 La PlataProvincia de Buenos AiresArgentina COnICET Godoy Cruz 2290C1425FQB Buenos AiresArgentina Facultad de Ciencias Agrariasy Forestales Universidad Nacional de La PlataCalle 60y 1181900 La PlataProvincia de Buenos AiresArgentina Facultad de Ciencias Forestales Universidad Nacional de MisionesBertoni 124 km 33380 EldoradoProvincia de MisionesArgentina

Forest disturbances at gap levels are one of the most important events for the regeneration and establishment of intermediate tree *** canopy openings expose plants to high light intensity and high evaporative demands that stress shade-acclimated ***,the slow closure of gaps reduces light availability to plants established when the incident irradiation was *** work evaluated the morphological and physiological acclimation of Cabralea canjerana(Vell)*** to sudden and to gradual changes in canopy cover.A pot experiment was carried out with plants exposed to a sudden opening.A few days after the light shock,plants rapidly increased photosynthetic rates and decreased leaf water *** two months,plants activated physiological responses at leaf and whole plant levels to high light and water stresses,e.g.,increased stoma-tal conductance,stomatal index and reduction of leaf:fine roots ratio and *** seven months,hydraulic conductivity of petioles and the whole leaf increased,and growth was much higher than plants that remained under the *** a field experiment in gaps in the rainforest,plants acclimated to all canopy *** years after planting,growth was maximum in open environments within the gaps,even if the canopy closed during the first 20 months after *** conclusion,if this species is planted to enrich the rainforest,positions within gaps with lower canopy cover should be chosen and gap closure will not affect *** manage *** natural regeneration,the opening of gaps and removal of understory will increase survival and growth without the risk that the stress caused by these sudden openings could lead to the death of ***-bining pot and field experiments helps to understand the autecology of trees with particular ecological interest,and to build sound restoration practices.

关键词： Cabralea canjerana Atlantic forest Abiotic stress Regeneration Seedling

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Calibration of the DEM sliding friction and rolling friction parameters of a cohesionless bulk material

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Particuology 2024年第9期92卷 126-139页

作者： Jonatan marín Pérez Tugrul Comlekci Yevgen Gorash Donald MacKenzie University of Strathclyde 75 Montrose StreetG11XJGlasgowUnited Kingdom

The discrete element method(DEM)has become a valuable tool for understanding the mechanical behaviour of granular assemblies,however,the accuracy of the DEM simulations depends on several interaction parameters such as the sliding friction and rolling friction ***,these parameters are estimated using bulk calibration approach(BCA)where the draw down test has been suggested as an effective way to approach these *** test provides up to four bulk criteria,the angle of repose,shear angle,mass flow rate and the mass loss which are used to narrow down the possible ***,there is still more research needed around it to fully understand how this methodology *** experimental and numerical study was carried out using the draw down test to assess the influence of different mass flow rates and particle shapes on DEM parameters for a cohesionless bulk *** is concluded that use of multi-sphere particles and three aperture sizes in the draw down test to calibrate the sliding and rolling friction parameters of a cohesionless bulk material can converge to a small feasible region in which a single combination of the friction coefficients can be *** calibrated sliding and rolling friction coefficients were validated using multi-sphere particles,where the maximum deviation was 5.9%from the experimental values.

关键词： Discrete element method Calibration Draw down Sliding friction Rolling friction Particle shape

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Omics-based biomarkers as useful tools in metabolic dysfunctionassociated steatotic liver disease clinical practice:How far are we?

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World Journal of Gastroenterology 2024年第14期30卷 1982-1989页

作者： Julieta Trinks maría F Mascardi Adrián Gadano Sebastián marciano Instituto de Medicina Traslacional e Ingeniería Biomédica-Consejo nacional de Investigaciones Científicas y Técnicas-Instituto Universitario del Hospital Italiano-Hospital Italiano de Buenos Aires Ciudad Autónoma de Buenos Aires C1199ACLArgentina Consejo nacional de Investigaciones Científicas y Técnicas Ciudad Autónoma de Buenos Aires C1425FQBArgentina Liver Unit Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina Department of Research Hospital Italiano de Buenos AiresCiudad Autónoma de Buenos Aires C1199DFArgentina

Unmet needs exist in metabolic dysfunction-associated steatotic liver disease(MASLD)risk *** ability to identify patients with MASLD with advanced fibrosis and at higher risk for adverse outcomes is still *** novel biomarkers could represent a meaningful improvement to current risk *** this aim,omics technologies have revolutionized the process of MASLD biomarker discovery over the past *** the research in this field is thriving,much of the publication has been haphazard,often using single-omics data and specimen sets of convenience,with many identified candidate biomarkers but lacking clinical validation and *** we incorporate these biomarkers to direct patients’management,it should be considered that the roadmap for translating a newly discovered omics-based signature to an actual,analytically valid test useful in MASLD clinical practice is rigorous and,therefore,not easily *** article presents an overview of this area’s current state,the conceivable opportunities and challenges of omics-based laboratory diagnostics,and a roadmap for improving MASLD biomarker research.

关键词： Metabolic dysfunction-associated steatotic liver disease non-alcoholic steatohepatitis Biomarker Risk stratification Omics

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Endotoxin-induced alterations of adipose tissue function:a pathway to bovine metabolic stress

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1391-1407页

作者： Miguel Chirivi G.Andres contreras Department of Large Animal Clinical Sciences Michigan State UniversityEast LansingMIUSA

During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.

关键词： Adipose tissue dysfunction Endotoxin Inflammation Insulin resistance

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Habitat and food preferences of European rabbits in core and edge populations along the invasion front PatagoniaMonte,Argentina

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Current Zoology 2024年第3期70卷 310-319页

作者： Sabrina Yasmin Bobadilla maría A.Dacar Fabián M.Jaksic Ricardo A.Ojeda maría Fernanda Cuevas Ecología de Mamíferos de Tierras Secas IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Laboratorio de Filogeografía Taxonomía Integrativa y Ecología(LFTIE)IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Center of Applied Ecology and Sustainability(CAPES) Pontifcia Universidad Católica de ChileAv.Libertador Bernardo O'Higgins 340Santiago 8320000Región MetropolitanaChile

The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of *** Adaptive Flexibility Hypothesis states that populations at the range edge(new populations)will exhibit greater fexibility in the use of resources compared with populations located in the range core(older populations).The objective of this work was to compare the rabbit’s use of spatial and trophic resources in relation to the establishment time of their *** sampling was carried out for 2 years(2017 and 2018)in sites with different establishment times for rabbit *** sampling stratifed by type of habitat was applied using 115 fxed strip transects of 1,000 m^(2) laid out across the study *** rabbit signs were recorded in each transect,and environmental and anthropic variables were *** results show that the individuals from the range edge are more selective in the use of habitat than those from the range *** the microhabitat level,we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to *** a trophic perspective,rabbits could show fexible adjustment to novel conditions and environments in the range *** variability in resource use by the European rabbit confrms its ecological fexibility,pivotal for their advance toward new environments in Argentina.

关键词： Arid ecosystems invasive species novel environments range invasion spatial use trophic use

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Experimental implementation of phase triplicator gratings in a spatial light modulator

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Chinese Optics Letters 2024年第2期22卷 64-69页

作者：高尚 maría del mar Sánchez-López Ignacio Moreno Instituto de Bioingeniería Universidad Miguel HernándezElche 03202Spain Departamento de Física Aplicada Universidad Miguel HernándezElche 03202Spain Departamento de Ciencia de Materiales Óptica y Tec.Electr´onicaUniversidad Miguel HernándezElche 03202Spain

In this work,we compare different methods for implementing a triplicator,a phase grating that generates three equiintense diffraction *** design with optimal efficiency features a continuous phase profile,which cannot be easily reproduced,and is typically affected by *** compare its performance with binary and sinusoidal phase *** also analyze the effect of quantizing the phase ***,a random approach is adopted to eliminate the additional harmonic *** all cases,a liquid-crystal-on-silicon spatial light modulator is employed to experimentally verify and compare the different approaches.

关键词： diffraction gratings phase modulation triplicator spatial light modulators

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Remediation of amide pesticide-polluted soils by combined solarization and ozonation treatment

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Pedosphere 2024年第3期34卷 641-651页

作者： Isabel GARRIDO Carmen MmarTInEZ Pilar FLORES Pilar HELLIn Fulgencio contreras Jose FEnOLL Department of Sustainability and Quality Group of Fruit and Vegetable Products Instituto Murciano de Investigacion y Desarrollo Agrario y MedioambientalLa Alberca 30150(Spain)

Agriculture has a close relationship with nature,but it can also be the source of negative and permanent environmental *** use of pesticides in modern agriculture is a common practice,but their side effects on the environment cannot be *** this study,we evaluated a combination of solarization and ozonation techniques for the elimination of six amide pesticides(boscalid,chlorantraniliprole,cyflufenamid,fluopyram,napropamide,and propyzamide)in *** experiments were performed with four different soils to assess the efficiency of this methodology at different soil temperatures and ozone dosages under laboratory conditions,and then a greenhouse pot experiment was conducted under controlled conditions during *** days after the onset of the experiments,higher degradation percentages of amide pesticides were observed in ozonized soils than in other treated soils,particularly when ozone was applied at 10 cm soil *** results show that the utilization of ozonation,along with solarization,represents a valid method for degrading residues of the studied pesticides and suggest that this combined technology may be a promising tool for remediating pesticide-polluted soils.

关键词： intermediate ozone pesticide degradation pesticide residue polyethylene film remediation technique

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Inversion of walkaway VSP data in the presence of lateral velocity heterogeneity

Energy Geoscience

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Energy Geoscience 2024年第2期5卷 304-313页

作者： Vladimir Grechka Ilya Tsvankin Pedro contreras CWP Department of GeophysicsColorado School of MinesGoldenCO80401USA PDVSA-InTEVEP Apartado 76343Caracas1070AVenezuela Borehole Seismic LLC USA Department of Physics ULAVenezuela

Multi-azimuth walkaway vertical seismic profiling is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy ***,this technique requires the assumption of lateral homogeneity,which makes the horizontal slowness components at depths of downhole receivers equal to those measured at the *** violations of this assumption,such as lateral heterogeneity or nonzero dip of intermediate interfaces,lead to distortions in reconstructed slowness surfaces and,consequently,to errors in estimated anisotropic *** this work,we relax the assumption of lateral homogeneity and discuss how to correct vertical seismic profile data for weak lateral *** describe a procedure of downward continuation of recorded traveltimes that accounts for the presence of both vertical inhomogeneity and weak lateral heterogeneity,which produces correct slowness surfaces at depths of downhole receivers,noticing that sufficiently dense receiver coverage along a borehole is required to separate influences of vertical and lateral heterogeneity on measured traveltimes and obtain accurate estimates of the slowness *** the slowness surfaces are found and a desired type of anisotropic model to be inverted is selected,the corresponding anisotropic parameters,providing the best fit to the estimated slownesses,can be *** invert the slowness surfaces of P-waves for parameters of the simplest anisotropic model describing dipping fractures(transversely isotropic medium with a tilted symmetry axis).Five parameters of this model,namely,the P-wave velocity V0 in the direction of the symmetry axis,Thomsen's anisotropic coefficients e and d,the tilt n,and the azimuth b of the symmetry axis,can be estimated in a stable manner when maximum source offset is greater than half of receiver depth.

关键词： Walkaway vertical seismic profile Lateral velocity heterogeneity Anisotropic parameter estimation Vertical inhomogeneity

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Transcriptomic responses to drought stress in the Patagonian southern beech nothofagus alpina

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Ecological Processes 2024年第2期13卷 192-203页

作者： Rita maria Lopez Laphitz maría Verónica Arana Santiago Agustín Varela Leandro Aníbal Becker Carolina Soliani maría marta Azpilicueta Paula marchelli nicolás Bellora Instituto de Diversidad y Evolución Austral (CEnPAT COnICET ) Instituto de Investigaciones Forestales y Agropecuarias Bariloche (IFAB InTA COnICET ) Instituto de Tecnologías nucleares para la Salud (COnICET )

Background Deciphering the genetic architecture of drought tolerance could allow the candidate genes identification responding to water stress. In the Andean Patagonian forest, the genus nothofagus represents an ecologically relevant species to be included in different genomic studies. These studies are scarce in South American ecosystems however represent an important source of genomic data in order to interpret future climate-change environment scenarios of these emblematic forests. Here, we achieved the assemblage of the transcriptome of n. alpina while searching for key genes of activated or suppressed metabolic pathways in response to drought *** De novo transcriptome assembly resulted in 104,030 transcripts. Following confirmation of drought conditions, based on reduction of leaf water potential and stomatal conductance, a differential gene expression analysis resulted in 2720 significantly expressed genes(1601 up-regulated and 1119 down-regulated). Enrichment analysis(over-representation analysis and gene set enrichment analysis) resulted in more than one hundred stress-responsive term ontologies(i.e. biological processes) and pathways. Terms such as response to abscisic acid and pathways such as plant hormone signal transduction or starch and sucrose metabolism were over-represented. Protein–protein interaction assessment resulted in networks with significantly expressed top common hub gene clusters(e.g. planttype cell wall biogenesis among down-regulated or ABA-signalling among up-regulated). These networks evidenced important regulators at gene expression such as transcriptional *** Responses of n. alpina seedlings to drought stress were evidenced by the activation of several genes linked to GO biological processes and KEGG pathways, which were mainly based on over-expression of specific protein kinases, phosphatases, synthases and transcription factors. This suggests an up-regulation of signalling pathways, triggered through pla

关键词： Climate change Differential gene expression Hub genes Patagonia Temperate forest

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