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A novel surface mesh deformation method for handling wing-fuselage intersections

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Chinese Journal of Aeronautics 2017年第1期30卷 264-273页

作者： Mario Jaime Martin-burgos daniel González-Juárez Esther Andrés-Pérez Fluid Dynamics Branch National Institute for Aerospace Technology (INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Engineering Department lngenieria de Sistemas para la Defensa de Espana (ISDEFE-INTA) Ctra. De Ajalvir km. 4.5 28850 Torrejon de Ardoz Spain Technical University of Madrid (UPM) Ronda de Valencia 3 28012 Madrid Spain

This paper describes a method for mesh adaptation in the presence of intersections, such as wing-fuselage. Automatic optimization tools, using Computational Fluid Dynamics（CFD） simulations, face the problem to adapt the computational grid upon deformations of the boundary surface. When mesh regeneration is not feasible, due to the high cost to build up the computational grid, mesh deformation techniques are considered a cheap approach to adapt the mesh to changes on the geometry. Mesh adaptation is a well-known subject in the literature; however, there is very little work which deals with moving intersections. Without a proper treatment of the intersections,the use of automatic optimization methods for aircraft design is limited to individual *** proposed method takes advantage of the CAD description, which usually comes in the form of Non-Uniform Rational B-Splines（NURBS） patches. This paper describes an algorithm to recalculate the intersection line between two parametric surfaces. Then, the surface mesh is adapted to the moving intersection in parametric coordinates. Finally, the deformation is propagated through the volumetric mesh. The proposed method is tested with the DLR F6 wing-body configuration.

关键词： Aerodynamic shape optimization Computational fluid dynamics Computer-assisted design Geometry parameterizationMesh deformation Non-Uniform Rational B-Splines

A Survey of Genetic Diversity of the Weedy Species <i>Ipomoea lacunosa</i>L. in the USA Mid-South

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American Journal of Plant Sciences 2011年第3期2卷 396-407页

作者： Nilda R. burgos daniel O. Stephenson Hesham A. Agrama Lawrence R. Oliver Jason A. Bond 不详

Morningglories (Ipomoea spp.) are among the most troublesome weedy species in agroecological environments. Ipomoea lacunosa is one of the most prevalent of these species. Localized adaptations resulted in the evolution of several I. lacunosa ecotypes in North America, which could potentially impact its response to crop management practices. To evaluate the genetic diversity and population structure of I. lacunosa populations, we amplified inter-simple sequence repeats loci by polymerase chain reaction (ISSR-PCR) of 64 accessions using 14 ISSR primers for Ipomoea. Of these, 64 polymorphic fragments were scored. Analysis of Nei’s genetic distance (GD) values placed the accessions into four genotypic clusters, two of which were composed primarily of accessions from Arkansas and Mississippi with GD between clusters of 0.318. The overall GD was 0.238, indicating a narrow genetic base. Population structure analysis determined three ancestral subgroups, with the majority of Arkansas and Mississippi accessions separated into two subgroups. The existence of various genotypes and ecotypes of I. lacunosa demonstrates the evolutionary diversification of this weedy species as it adapts to new colonized environments and agricultural activities.

关键词： DNA Fingerprinting Genetic Diversity Ipomoea ISSR Morningglory Species Morningglory Genotypes Population Structure

Critically ill patients with cancer: A clinical perspective

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World Journal of Clinical Oncology 2020年第10期11卷 809-835页

作者： Frank daniel Martos-Benítez Caridad de Dios Soler-Morejón Karla Ximena Lara-Ponce Versis Orama-Requejo Dailéburgos-Aragüez Hilev Larrondo-Muguercia Rahim W Lespoir Intensive Care Unit 8B Hermanos Ameijeiras HospitalHavana 10300Cuba

Cancer patients account for 15%of all admissions to intensive care unit(ICU)and 5%will experience a critical illness resulting in ICU *** rates have decreased during the last decades because of new anticancer therapies and advanced organ support *** early critical care and organ support is associated with improved survival,timely identification of the onset of clinical signs indicating critical illness is crucial to avoid *** article focused on relevant and current information on epidemiology,diagnosis,and treatment of the main clinical disorders experienced by critically ill cancer patients.

关键词： Acute respiratory failure Cancer Cardiotoxicity Chemotherapy Critical care Infection Mechanical ventilation Neutropenia Postoperative Sepsis

Endoscopic ultrasound-guided through-the-needle microforceps biopsy and needle-based confocal laser-endomicroscopy increase detection of potentially malignant pancreatic cystic lesions:A single-center study

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World Journal of Gastrointestinal Endoscopy 2022年第3期14卷 129-141页

作者： Carlos Robles-Medranda Juan I Olmos Miguel Puga-Tejada Roberto Oleas Jorge Baquerizo-burgos Martha Arevalo-Mora Raquel Del Valle Zavala Joao Autran Nebel daniel Calle Loffredo Hannah Pitanga-Lukashok Gastroenterology and Endoscopy Division Instituto Ecuatoriano de Enfermedades DigestivasGuayaquil 090505Ecuador

BACKGROUND Currently,there is insufficient data about the accuracy in the diagnosing of pancreatic cystic lesions(PCLs),especially with novel endoscopic techniques such as with direct intracystic micro-forceps biopsy(mFB)and needle-based confocal laser-endomicroscopy(nCLE).AIM To compare the accuracy of endoscopic ultrasound(EUS)and associated techniques for the detection of potentially malignant PCLs:EUS-guided fine needle aspiration(EUS-FNA),contrast-enhanced EUS(CE-EUS),EUS-guided fiberoptic probe cystoscopy(cystoscopy),mFB,and *** This was a single-center,retrospective *** identified patients who had undergone EUS,with or without additional diagnostic techniques,and had been diagnosed with *** determined agreement among malignancy after 24-mo follow-up findings with detection of potentially malignant PCLs via the EUSguided techniques and/or EUS-guided biopsy when available(EUS malignancy detection).RESULTS A total of 129 patients were included, with EUS performed alone in 47/129. In 82/129 patients,EUS procedures were performed with additional EUS-FNA (21/82), CE-EUS (20/82), cystoscopy(27/82), mFB (36/82), nCLE (44/82). Agreement between EUS malignancy detection and the 24-mo follow-up findings was higher when associated with additional diagnostic techniques thanEUS alone [62/82 (75.6%) vs 8/47 (17%);OR 4.35, 95%CI: 2.70-7.37;P < 0.001]. The highestmalignancy detection accuracy was reached when nCLE and direct intracystic mFB were bothperformed, with a sensitivity, specificity, positive predictive value, negative predictive value andobserved agreement of 100%, 89.4%, 77.8%, 100% and 92.3%, respectively (P < 0.001 comparedwith EUS-alone).CONCLUSIONThe combined use of EUS-guided mFB and nCLE improves detection of potentially malignantPCLs compared with EUS-alone, EUS-FNA, CE-EUS or cystoscopy.

关键词： Pancreatic cysts Endoscopic ultrasound-guided fine-needle aspiration Confocal microscopy Image-guided biopsy

Genetic mapping and survey of powdery mildew resistance in the wild Central Asian ancestor of cultivated grapevines in Central Asia

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Horticulture Research 2020年第1期7卷 1444-1458页

作者： Summaira Riaz Cristina M.Menéndez Alan Tenscher daniel Pap M.Andrew Walker Department of Viticulture and Enology University of CaliforniaDavisCA 95616USA Instituto de Ciencias de la Vid y del Vino(ICVV) Universidad de La Rioja-CSICGobierno de La RiojaCarretera de Burgos Km6Finca La GrajeraLogroñoLa Rioja 26007Spain

Cultivated grapevines(Vitis vinifera)lack resistance to powdery mildew(PM)with few *** to this pathogen within *** has been reported in earlier studies and identified as the Ren1 locus in two Central Asian table grape *** PM-resistant cultivated varieties and accessions of the wild ancestor *** *** were soon identified raising questions regarding the origin of the *** this study,F1 breeding populations were developed with a PM susceptible *** *** breeding line and a PM-resistant *** *** was carried out with five Ren1 locus linked SSR markers.A PM resistance locus explaining up to 96%of the phenotypic variation was identified in the same genomic position,where the Ren1 locus was previously *** SSR marker alleles linked with the resistance locus were *** report results of PM resistance in multiple accessions of *** collected as seed lots or cuttings from five countries in the Caucasus and Central Asia.A total of 20 females from 11 seed lots and 19 males from nine seed lots collected from Georgia,Armenia,and Azerbaijan were resistant to *** male and one female plant collected as cuttings from Afghanistan and Iran were also resistant to *** analysis of markers linked with the Ren1 locus in conjunction with disease evaluation data found a high diversity of allelic haplotypes,which are only possible via recombination events occurring over a long time *** analysis of two alleles of the SSR marker that cosegregates with the resistance found SNPs that were present in the wild progenitor and in cultivated *** levels of PM resistance among the tested accessions were also *** lines of evidence suggest that the powdery mildew fungus may have been present in Asia for a longer time than currently thought,giving the wild progenitor *** *** time to coevolve with and develo

关键词： breeding resistance Central

FeNb在钢液中的溶化行为及在钢包精炼过程中提高Nb收得率的最佳工艺

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世界钢铁 2010年第6期10卷 44-48+58页

作者： Edmundo burgos Cruz daniel Pallos Fridman Marcelo C Carboni Rogério Contato Guimares Marcos A Stuart Nogueira Ferdinando Luiz Cavallante 王厚昕巴西矿冶公司

阐述了标准铌铁(FeNb)的微观组织特性及其溶入钢液中的研究结果。在实验室的感应炉中进行了不同温度下的非连续试验,分析了固相FeNb与钢液凝固层界面的微观组织,并与原始FeNb粒子的微观组织进行了对比。这些试验研究结果可以阐释FeNb的... 详细信息

阐述了标准铌铁(FeNb)的微观组织特性及其溶入钢液中的研究结果。在实验室的感应炉中进行了不同温度下的非连续试验,分析了固相FeNb与钢液凝固层界面的微观组织,并与原始FeNb粒子的微观组织进行了对比。这些试验研究结果可以阐释FeNb的溶解机制和它在不同炼钢温度下的融入动力学条件。标准FeNb在钢水中溶解的试验结果证实FeNb颗粒的溶解速率高于有关文献中报告的结果,它们认为FeNb粒子的熔化温度高(>1600℃),所以在其模型中假定FeNb的溶解仅是通过固相粒子的扩散实现。本项工作得到的试验证据为标准FeNb的溶解机理提供了一种新的说法:在1500～1510℃受其共晶区的熔化行为控制,在1530～1575℃温度范围内则由初始板条相的熔化行为所主导,也就是说,均低于1600℃左右的炼钢温度。根据这些研究结果和炼钢厂已有的生产经验,对于微合金化钢在二次精炼阶段加入FeNb推荐了最优的工艺。

关键词： FeNb 铌铁溶解微合金化钢炼钢

Dissolution of FeNb in liquid steel and best practices to increase niobium recovery during ladle refining

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Baosteel Technical Research 2010年第S1期4卷 19-页

作者： Edmundo burgos CRUZ daniel Pallos FRIDMAN Marcelo C CARBONI Rogerio Contato GUIMARAES Marcos A Stuart NOGUEIRA Ferdinando Luiz CAVALLANTE CBMM Araxa MGBrasil CBMM Sao Paulo SPBrasil Sao Paulo Polytechnic School Brasil

This paper presents a microstructural characterization of standard ferroniobium(FeNb) and a study of its dissolution in *** dissolution trials at different temperatures were carried out in a laboratory induction *** microstructure at the interface between solid FeNb and frozen steel was analyzed and compared with the original FeNb *** results allowed clarifying both the FeNb dissolution mechanism and its incorporation kinetics at steelmaking *** results from the dissolution of standard FeNb in liquid steel proved that the dissolution rates of FeNb particles were higher than those reported in the pertinent literature,where models assume that FeNb dissolves only by the diffusion of solid particles due to its high melting temperatures(over 1 600℃).Most recent FeNb phase diagrams and DTA analyses have shown that standard FeNb begins to melt down below 1 600℃.The experimental evidences in this work have led to the adoption of a new description of the dissolution mechanism whereby standard FeNb dissolves predominantly by the melting of its eutectic zones at 1500℃to 1510℃and,later on,by the melting of the primary laths between 1530℃and 1575℃,i.e.,below the steelmaking temperatures of around 1 600℃.Based on these results and on previous melting-shop experience,this paper recommends the best practices for the addition of FeNb during the microalloyed steels secondary refining phase.

关键词： FeNb ferroniobium dissolution microalloyed steel steelmaking

Rectification of oxygen transfer through the rat colonic epithelium

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World Journal of Gastrointestinal Pathophysiology 2017年第2期8卷 59-66页

作者： Fernando D Saraví Graciela E Carra daniel A Matus Jorge E Ibánez Institute of Physiology Faculty of Medical SciencesNational University of Cuyo Department of Surgery Faculty of Medical SciencesNational University of Cuyo Mario H. burgos Institute of Histology and Embryology CONICETFaculty of Medical SciencesNational University of Cuyo

AIM To assess whether higher sensitivity of colonic epithelium to hypoxia at the serosal side is associated with oxygen transfer *** Rats were fed either with normal chow or a lowsodium diet. Tissues were mounted as flat sheets in a modified, airtight Ussing chamber with oxygen meters in each hemichamber. Mucosal samples from normal diet animals were studied under control conditions, in low-chloride solution and after adding chloride secretion inhibitors and chloride secretagogues. Samples from sodium-deprived rats were studied before and after ouabain addition. In separate experiments, the correlation between short-circuit current and oxygen consumption was analyzed. Finally, hypoxia was induced in one hemichamber to assess the relationship between its oxygen content and the oxygen pressure differencebetween both hemichambers. RESULTS In all studied conditions, oxygen consumption was larger in the serosal hemichamber than in the mucosal one(P = 0.0025 to P < 0.0001). Short-circuit current showed significant correlation with both total oxygen consumption(r = 0.765; P = 0.009) in normoxia and oxygen consumption in the serosal hemichamber(r = 0.754; P = 0.011) during mucosal hypoxia, but not with oxygen consumption in the mucosal hemichamber. When hypoxia was induced in the mucosal hemichamber, an oxygen pressure difference of 13 k Pa with the serosal hemichamber was enough to keep its oxygen content constant. However, when hypoxia was induced in the serosal hemichamber, the oxygen pressure difference with the mucosal hemichamber necessary to keep its oxygen content constant was 40 k Pa(P < 0.0001). CONCLUSION Serosal oxygen supply is more readily available to support short-circuit current. This may be partly due to a rectifying behavior of transepithelial oxygen transfer.

关键词： Colonic epithelium Hypoxia Oxygen diffusion Short-circuit current Ussing chamber