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Finite Element Structural Analysis of Buried Pipelines

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Modern Mechanical Engineering 2022年第2期12卷 27-44页

作者： Casanova-del-angel Francisco Córdova-Castillo alejandra Escuela Superior de Ingeniería y Arquitectura UP ALM SEPI of the Instituto Politécnico Nacional Mexico City Mexico

This document uses previous results (which we call the first stage), for the development of a computer model based on finite elements under the FEAP programmer, to carry out a structural analysis of a pipeline. For this purpose, we used environmental variables that we believe influence the failure of buried pipelines such as the internal pressure of fluid, the type of support used, the temperature at which the pipelines work, the type of soil and the stiffness of the soil acting on it. Once the model was finalized, analyses were made with each of the variables separately and combined to observe the behavior of the pipeline, finding the most unfavorable case that indicates the main causes that led to its failure.

关键词： Duct Finite Element Buried Pipeline Material Creep Thermal Conditions Soil Springs

G2/M inhibitors as pharmacotherapeutic opportunities for glioblastoma:the old,the new,and the future

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Cancer Biology & Medicine 2018年第4期15卷 354-374页

作者： angel Mauricio Castro-Gamero Julia alejandra Pezuk Maria Sol Brassesco Luiz Gonzaga Tone Human Genetics Laboratory Institute of Natural SciencesFederal University of Alfenas(UNIFAL-MG)Alfenas 37130-001Brazil Biotechnology and Innovation in Health Program and Pharmacy Program Anhanguera University Sao Paulo(UNIANSP)Sao Paulo 05145-200Brazil Department of Biology Faculty of PhilosophySciences and Letters at Ribeirao PretoUniversity of Sao PauloRibeirao Preto 14040-901Brazil Department of Pediatrics Department of Genetics Ribeirao Preto School of MedicineUniversity of Sao PauloRibeirao Preto 14049-900Brazil

Glioblastoma(GBM) is one of the deadliest tumors and has a median survival of 3 months if left untreated. Despite advances in rationally targeted pharmacological approaches, the clinical care of GBM remains palliative in intent. Since the majority of altered signaling cascades involved in cancer establishment and progression eventually affect cell cycle progression, an alternative approach for cancer therapy is to develop innovative compounds that block the activity of crucial molecules needed by tumor cells to complete cell division. In this context, we review promising ongoing and future strategies for GBM therapeutics aimed towards G2/M inhibition such as anti-microtubule agents and targeted therapy against G2/M regulators like cyclin-dependent kinases,Aurora inhibitors, PLK1, BUB, 1, and BUBR1, and survivin. Moreover, we also include investigational agents in the preclinical and early clinical settings. Although several drugs were shown to be gliotoxic, most of them have not yet entered therapeutic trials. The use of either single exposure or a combination with novel compounds may lead to treatment alternatives for GBM patients in the near future.

关键词： Chemotherapy PLK1 AURK survivin BUB BUR1

Metallography of an Underground Oil Pipeline

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Open Journal of Metal 2018年第3期8卷 35-54页

作者： Francisco Casanova-del-angel alejandra Córdova-Castillo Sección de Estudios de Posgrado e Investigación Escuela Superior de Ingeniería y Arquitectura Unidad Profesional Adolfo López Mateos Instituto Politécnico Nacional Mexico City Mexico

The purpose of this article is to show a metallographic analysis of an underground pipeline taken out of operation upon failure. The pipeline had an 8.89 cm (3.5”) diameter and a 7 mm thickness. The study was based on a 45 cm long pipe sample, visibly and entirely corroded, with a fish-mouth crack along its length. The work contributes to finding new ways to prevent structural failure, which has high-impact consequences from the point of view of production, damage to property, pollution, and risks to human live. Through this analysis the knowledge on behavior of failures in terrestrial ducts has been extended. Development of the research included metallographic, chemical, and mechanical tests on the sample in order to know the composition of the material, its strength and its physical conditions upon taking it out of operation. After the analysis of the laboratory tests, the physical and chemical features were compared to existing national and international regulations, which allowed a specific characterization of the conditions of the sample. In accordance with the regulations, the grade of the pipe was between ×65 and ×70. Tensile testing was carried out to obtain mechanical properties in order to corroborate the grade of pipeline steel and complement the metallographic analysis.

关键词： Metallography Microscopy Oil Pipeline Failure Tensile Testing

Crustacean parasites associated with hermit crabs from the western Mediterranean Sea,with first documentation of egg predation by the burrowing barnacle Trypetesa lampas(Cirripedia:Acrothoracica:Trypetesidae)

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Integrative Zoology 2011年第1期6卷 13-27页

作者： Jason D.WILLIAMS alejandra GALLARDO angela E.MURPHY Department of Biology Hofstra UniversityHempsteadNYUSA

Parasitic isopods(family Bopyridae)and burrowing barnacles(family Trypetesidae)infesting hermit crabs were investigated from shallow subtidal collections made along the southeastern coast of Spain in 2009.A total of 713 specimens of Clibanarius erythropus(Latreille,1818)and 82 Calcinus tubularis(L.,1767)were *** shells and worm tubes inhabited by hermit crabs were collected by hand while snorkeling and were cracked to determine host species,size,sex and presence of *** species of bopyrid isopods were found on ***:the branchial parasite Bopyrissa fraiseii(Carayon,1943)and the abdominal parasite Parathelges cardonae Codreanu and Codreanu in Codreanu,*** all *** examined,Bopyrissa fraiseii was found on 0.6%of hermit crabs and *** was found on 0.3%.A redescription of *** is provided and the species is documented with light and scanning electron microscopy for the first *** Calcinus tubularis harbored parasitic isopods,but one specimen was parasitized by an unidentified rhizocephalan barnacle of the genus Septosaccus(1.2%).The burrowing barnacle Trypetesa lampas(Hancock,1849)was found associated with both hermit crab species and evidence of predation on host eggs by this barnacle is shown for the first *** lampas was found in 4.2%of the shells *** present study expands our knowledge of the parasite fauna of hermit crabs from the Mediterranean Sea and indicates that additional research is needed to determine the impact of trypetesid egg predators on hermit crab populations.

关键词： Bopyridae egg predator Isopoda parasitism Rhizocephala

Potential Species Distribution and Richness of Ixodidae Ticks Associated with Wild Vertebrates from Michoacán, Mexico

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Journal of Geographic Information System 2014年第5期6卷 467-477页

作者： Margarita Vargas-Sandoval angel G. Priego-Santander alejandra Larrazábal Carolina G. Sosa-Gutiérrez Blanca Lara-Chávez Teresita Avila-Val Facultad de Agrobiología “Presidente Juárez” Universidad Michoacana de San Nicolás de Hidalgo Uruapan México Centro de Investigaciones en Geografía Ambiental UNAM Antigua Carretera a Pátzcuaro No. 8701 ExHacienda de San José de la Huerta Morelia México Unidad de Investigación Médica de Enfermedades Infecciosas y Parasitarias Hospital de Pediatría Centro Médico Nacional Siglo XXI México DF México

Ticks are regarded as the most relevant vectors of disease-causing pathogens in domestic and wild animals. The diversity of Ixodidae is known for a very small number of ***?are represented by 26 species, and?in?2007 the first reported ticks vectors in Mexico for the causal agent of Lyme disease. Recent rise in tick-borne disease in many parts of the world is a phenomenon in need of an explanation. The main objective of the present work was to map at a regional scale (1:2,000,000)?of?the distribution of ticks of the family Ixodidae that are potentially present on the wild fauna of state of Michoacan, Mexico. We compiled all available literature on ticks at a national level together with complete cartographic and bibliographic georeferenced information of the distribution of hosts in order to build a spatial database in ArcView 3.3. The results indicated that the wild fauna in the state’s territory could potentially include 31 species of ticks of Ixodidae. The map of potential species richness of ixodid ticks on the wild fauna of the state can be categorized into five classes of species richness. The highest potential concentration of ixodid species on wild fauna occurs in the volcanic area of Pico de Tancítaro.

关键词： Ticks Ixodidae Michoacán Geographic Distribution Potential Species Richness