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The effect of electrical current on lubricant film thickness in boundary and mixed lubrication contacts measured with ultrasound

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Friction 2024年第8期12卷 1882-1896页

作者： Julio A.CAO-ROMERO-GALLEGOS Saeid TAGHIZADEH oscar A.AGUILAR-ROSAS R.S.DWYER-JOYCE Leonardo I.FARFAN-cabrera Tecnologico de Monterrey Escuela de Ingeniería y CienciasAve.Eugenio Garza Sada 2501MonterreyN.L.64849México Department of Mechanical Engineering Leonardo Centre for TribologyUniversity of SheffieldSheffield S13JDUK

This work explores experimentally the effects of DC electrical currents on lubricant film thickness alteration in lubricated sliding steel contacts in the boundary and mixed regime as measured by *** experiments were performed in a two-electrode cell-based pin-on-disk tester instrumented with ultrasonic *** and electrified tribological tests were conducted on steel flat-on-flat contacts under various speeds and loads using both a mineral base oil and a gear *** thickness,coefficient of friction(CoF),and electrical contact resistance(ECR)were measured during short experiments(30 s)in unelectrified and electrified(1.5 and 3 A)*** results suggest that film thickness,CoF,and all ECR are altered by passing DC currents through the *** particular,film thickness increased and decreased,respectively,by applying electricity at the different speeds and loads *** alterations were majorly ascribed to oil viscosity decrease by local heat and surface oxidation caused by electrical discharge and break down at the interface.

关键词： electrified sliding ultrasonic measurement electric vehicles pin-on-disk

Root colonization by mycorrhizal INIFAP<sup>MR</sup>in barley seed treated with fungicide

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Agricultural Sciences 2013年第12期4卷 738-743页

作者： oscar A. grageda-cabrera Sarahyt S. González-Figueroa Mónica Guadalupe Lozano-Contreras Arturo Díaz-Franco Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP) Campo Experimental Bajío Celaya México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP) Campo experimental Mocochá Yucatán México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP) Campo experimental Río Bravo Rio Bravo México

The effect of barley seed treated with chlorothalonil fungicide on mycorrhizal root colonization was evaluated. The treatments were: 1) Seed with Mycorrhizal INIFAP?, one, two and three doses, and uninoculated seed;2) Seed with and without fungicide. Monthly seed plantings were performed with different storage time, looking forward to assessing the colonization degree of the roots. As revealed by the results, the seed treated with chlorothalonil did not lower the root colonization by Mycorrhizal INIFAP?;the chlorothalonil treatment had a 32.63% average root colonization, whereas without chlorothalonil, it was 36.46%. When the seed was treated with root colonization by Mycorrhizal INIFAP?, this was lower in the treatment with one dose;no significant difference was revealed by the treatments with either double or triple doses.?The colonization percentage was progressively decreased by seed storage. The root colonization by Mycorrhizal INIFAP?, throughout the inoculated seed storage time, remained constant and unchanged for the first six months, but then decreased in 50% within a 10-month period for both treated and not treated fungicide seed.

关键词： Chlorothalonil Hordeum vulgare Rhizophagus intraradices

Response of rice cultivation to biofertilizers in Campeche, Mexico

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Agricultural Sciences 2013年第12期4卷 715-720页

作者： Fermín Orona-Castro Mónica Guadalupe Lozano-Contreras Martín Tucuch-Cauich oscar A. grageda-cabrera Juan Medina-Mendez Arturo Díaz-Franco Esaú Ruiz-Sánchez Jesús Soto-Rocha Campo Experimental Bajío (INIFAP) Celaya México Campo Experimental Río Bravo (INIFAP) Rio Bravo México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP) Campo Experimental Edzna Campeche México Instituto Nacional de Investigaciones Forestales Agrícolas y Pecuarias (INIFAP) Campo Experimental Mococha Yucatán México Instituto Tecnológico de Conkal Conkal México

The activity of various biofertilizers on rice production (Sabanero A95) was evaluated in Palizada, Campeche, Mexico, in the wet season of 2009 (year one) and 2011 (year two). On year one, arbuscular mycorrhiza INIFAP? (Rhizophagus intraradices), Azospirillum brasilense plus arbuscular micorrhiza Rhizophagus sp., and chemical fertilizer (92, -92, -60 kg·ha-1) were evaluated, while on year two marine algae extracts, a consortium of growth promoting bacteria (Pseudomonas spp.) and a control (not fertilized) were evaluated. The results showed that there were no significant differences on grain yield among treatments during the year one. The average grain yield was 2,800 kg·ha-1. As for the year two, the highest grain yield was observed on plots fertilized with chemical fertilizer (3333 kg·ha-1), followed by plots treated with mycorrhiza INIFAP? (3000 kg·ha-1). The economic analysis for rice production in both years showed that the use of arbuscular mycorrhiza decreases the cost of production by 18.5% and 16.3%, which suggests that microbial inoculants might be good substitutes of chemical fertilizers in rice production.

关键词： Rice Wet Season Validation Biofertilizers

Current trends of liver cirrhosis in Mexico: Similitudes and differences with other world regions

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World Journal of Clinical Cases 2018年第15期6卷 922-930页

作者： Nahum Méndez-Sánchez Felipe Zamarripa-Dorsey Arturo Panduro Emma Purón-González Edgar Ulises Coronado-Alejandro Carlos Alejandro Cortez-Hernández Fátima Higuera de la Tijera José Luis Pérez-Hernández Eira Cerda-Reyes Heriberto Rodríguez-Hernández Vania César Cruz-Ramón oscar Lenin Ramírez-Pérez Nancy Edith Aguilar-Olivos Olga Fabiola Rodríguez-Martínez Samantha cabrera-Palma Guillermo cabrera-álvarez Liver Research Unit Medica Sur Clinic and Foundation Department of Gastroenterology Hospital "Juárez" of México Department of Molecular Biology in Me-dicine Civil Hospital of Guadalajara "Fray Antonio Alcalde" Department of Internal Medicine "Christus Muguerza "Super Specialty" Hospital" Monterrey Department of Gas-troenterology "University Hospital "Jose Eleuterio González" Monterrey Department of Gastroenterology "General Hospital of Mexico "Dr.Eduardo Liceaga" Department of Gastroenterology "Central Military Hospital" Faculty of Medicine and Nutrition Juárez University of the State of Durango Liver Clinic Regional General Hospital IMSS 1

AIM To investigate the main current etiologies of cirrhosis in *** We performed a cross-sectional retrospective multicenter study that included eight hospitals in different areas of Mexico. These hospitals provide health care to people of diverse social classes. The inclusion criteria were a histological, clinical, biochemical, endoscopic, or imaging diagnosis of liver cirrhosis. Data were obtained during a 5-year period(January 2012-December 2017). RESULTS A total of 1210 patients were included. The mean age was 62.5 years(SD = 12.1), and the percentages of men and women were similar(52.0% vs 48.0%). The most frequent causes of liver cirrhosis were hepatitis C virus(HCV)(36.2%), alcoholic liver disease(ALD)(31.2%), and nonalcoholic steatohepatitis(23.2%), and the least frequent were hepatitis B virus(1.1%), autoimmune disorders(7.3%), and other conditions(1.0%).CONCLUSION HCV and ALD are the most frequent causes of cirrhosis in Mexico. However, we note that non-alcoholic fatty liver disease(NAFLD) as an etiology of cirrhosis increased by 100% compared with the rate noted previously. We conclude that NAFLD will soon become one of the most frequent etiologies of liver cirrhosis in Mexico.

关键词： Alcoholic liver disease Hepatitis C virus Nonalcoholic steatohepatitis Liver cirrhosis

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铜——近期难转冷

证券导刊 2006年第5期 41-42页

作者： Goldman Sachs J Alberto Arias oscar cabrera 吴亚琴

本轮的铜景气周期将延续。通过假设几种不同的铜价来推断各种相应的结论,本文认为从铜资源的估值角度而言FreeportMcMoRan公司和PhelpsDodge公司的股票仍将为投资者提供最好的风险/回报率(尽管这两个公司2005年的股票走势已经很强劲)。... 详细信息

本轮的铜景气周期将延续。通过假设几种不同的铜价来推断各种相应的结论,本文认为从铜资源的估值角度而言FreeportMcMoRan公司和PhelpsDodge公司的股票仍将为投资者提供最好的风险/回报率(尽管这两个公司2005年的股票走势已经很强劲)。由于近期的数据显示了一个更长的铜景气周期(这些数据显示铜业公司将在盈利和潜在的多级扩张方面有积极变化),我们认为铜价高位带来的风险将有所降低。

关键词：景气周期铜价投资者回报率铜消费国家风险估值供应方股票走势供应中断