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The Fundamental Mechanisms of the Absorption Process of Si During Rapid Thermal Process

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材料科学与工程（中英文B版） 2012年第10期2卷 517-522页

作者： Ivaldo torres Cristobal Voz Ramon Alcubilla Grupo lOGOS Departamento EETS Facultad de Ingenierlas y Arquitecturas Universidad de Pamplona Km 1 Via a Bucaramanga Pamplona Norte de Santander Colombia Departament d'Engenyeria Electronica Universitat Politecnica de Catalunya C/ Gran Capita s/n Campus Nord 08074 Barcelona Espana

Prevalence of vacA, cagA and babA2 genes in Cuban Helicobacter pylori isolates

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World Journal of Gastroenterology 2009年第2期15卷 204-210页

作者： lino E torres Karelia Melián Arlenis Moreno Jordis Alonso Carlos A Sabatier Mayrín Hernández ludisleydis Bermúdez Boris l Rodríguez Department of Microbiology and Immunology Biotechnology Division National Centre for Scientif ic Research Ciudad de La Habana Cuba Department of Gastroenterology Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba Anatomopathology Department Medical and Chirurgic Research Centre (CIMEQ) Ciudad de La Habana Cuba

AIM： To investigate the prevalence of vacuolating cytotoxin （vacA）, cytotoxin associated gene A （cagA） and blood adhesion binding antigen （babA2） genotypes of Helicobacter pylori （H pylori） isolates from Cuban dyspeptic patients. METHODS： DNA was extracted from Hpylori-positive cultures taken from 130 dyspeptic patients. Genotyping was performed by PCR, using specific primers for vacA （s1, s2, m1, m2）, cagA and babA2 genes. Endoscopic observations and histological examinations were used to determine patient pathologies. RESUlTS： vacA alleles s1, s2, m1 and m2 were detected in 96 （73.8%）, 34 （26.2%）, 75 （57.7%） and 52 isolates （40%）, respectively, while the cagA gene was detected in 95 isolates （73.2%）. One hundred and seven isolates （82.3%） were babA2-positive. A significant correlation was observed between vacAs1m1 and cagA and between vacAs1ml and babA2 genotypes （P 〈 0.001 and P 〈 0.05, respectively） and between babA2 genotype and cagA status （P 〈 0.05）; but, no correlation was observed between vacAsl and babA2 genotypes. Eighty five （65.4%） and 73 （56.2%） strains were type 1 （vacAsl-cagA-positive） and ＂triplepositive＂（vacAs1-cagA-babA2-positive）, respectively, and their presence was significantly associated with duodenal ulcer （P 〈 0.01 and P 〈 0.001, respectively）. CONClUSION： The distribution of the main virulence factors in the Cuban strains in this study resembled that of the Western-type strains, and the more virulent H pylori isolates were significantly associated with duodenal ulcer, ulcer disease being the worst pathology observed in the group studied.

关键词： Cuban dyspeptic patients He/icobacterpylori vacA, cagA and babA

Research on arbuscular mycorrhizae in Cuba:a historical review and future perspectives

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Studies in Fungi 2021年第1期6卷 240-262页

作者： Furrazola E torres-Arias Y Ojeda-Quintana l Fors RO Rodríguez-Rodríguez R ley-Rivas JF Mena A González-González S Berbara Rll Queiroz MB Hamel C Goto BT Instituto de Ecología y Sistemática CITMA Carretera Varona 11835 e/Oriente y LinderoLa Havana 19CalabazarBoyerosLa HavanaCuba CUM Cumanayagua Universidad de Cienfuegos“Carlos R.Rodríguez”CienfuegosCuba Universidade Federal Rural do Rio de Janeiro Instituto de AgronomiaSeropedicaRJBrazil Instituto Nacional de Ciencias Agropecuarias(INCA) Gaveta Postal 1San Joséde las LajasMayabequeCuba Universidad de Temuco Chile Programa de Pós-graduação em Sistemática e Evolução CBUniversidade Federal do Rio Grande do NorteCampus Universitário59072-970NatalRNBrazil Quebec Research and Development Centre Agriculture and Agri-Food Canada2560 Hochelaga BlvdQuebec CityQCCanada G1V 2J3

This review presents the development of researches on arbuscular mycorrhizae(AM)conducted in Cuba,a tropical Caribbean island rich in *** key findings from this work are highlighted and presented as a stepping stone for future *** research has contributed to understand the diversity and functionality of AM in several tropical ecosystems,mainly evergreen forests,agroecosystems,sand dunes and *** were conducted in 10 out of 16 provinces reported 79 AM species,representing 25%of the known species *** researchers have a great deal of expertise in Glomeromycota taxonomy and have described 11 new species,of which six were not reported elsewhere in the ***,important studies conducted in Cuba have shed light on the mycotrophic plants,the role of AM in forest ecosystems,and their use in crop *** contribution of AM to ecosystem processes is a priority line of *** and multidisciplinary researches are necessary to define the role of AM symbioses and improve biogeochemical *** created Cuban Mycorrhizal Research Network will help to coordinate validation campaigns for various biofertilizers with training courses for Cuban farmers to disseminate the key results on *** the challenges for Cuban mycorrhizologists,molecular(genomic)techniques,stable isotopes and nuclear magnetic resonance should also be included as priority lines of research in the future.

关键词： Arbuscular mycorrhizal fungi diversity ecosystems mycorrhizal research symbiotic associations

Non-invasive delivery of levodopa-loaded nanoparticles to the brain via lymphatic vasculature to enhance treatment of Parkinson’s disease

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Nano Research 2021年第8期14卷 2749-2761页

作者： Tianqi Nie Zhiyu He Jinchang Zhu Kuntao Chen Gregory P.Howard Jesus Pacheco-torres II Minn Pengfei Zhao Zaver M.Bhujwalla Hai-Quan Mao lixin liu Yongming Chen School of Materials Science and Engineering Key Laboratory for Polymeric Composite and Functional Materials of Ministry of EducationSun Yat-sen UniversityGuangzhou 510275China Key laboratory of Marine Chemistry Theory and Technology Ministry of EducationOcean University of ChinaQingdao 266100China Department of Materials Science and Engineering Johns Hopkins University BaltimoreMD 21218USA Department of Biomedical Engineering Johns Hopkins School of Medicine BaltimoreMD 21205USA Institute for NanoBioTechnology Johns Hopkins UniversityBaltimoreMD 21218USA Division of Nuclear Medicine and Molecular Imaging Department of Radiology and Radiological Science Johns Hopkins School of MedicineBaltimoreMD 21205USA Translational Tissue Engineering Center Johns Hopkins School of MedicineBaltimoreMD 21287USA

levodopa(l-DOPA),a precursor of dopamine,is commonly prescribed for the treatment of the Parkinson’s disease(PD).However,oral administration of levodopa results in a high level of homocysteine in the peripheral circulation,thereby elevating the risk of cardiovascular disease,and limiting its clinical ***,we report a non-invasive method to deliver levodopa to the brain by delivering l-DOPA-loaded sub-50 nm nanoparticles via brain-lymphatic *** hydrophilic l-DOPA was successfully encapsulated into nanoparticles of tannic acid(TA)/polyvinyl alcohol(PVA)via hydrogen bonding using the flash nanocomplexation(FNC)process,resulting in a high l-DOPA-loading capacity and uniform size in a scalable *** analysis in a PD rat model demonstrated that the levels of dopamine and tyrosine hydroxylase,which indicate the dopaminergic neuron functions,were increased by 2-and 4-fold,*** disorders and cerebral oxidative stress of the rats were significantly *** formulation exhibited a high degree of biocompatibility as evidenced by lack of induced inflammation or other pathological changes in major *** antioxidative and drug-delivery platform administered through the brain-lymphatic vasculature shows promise for clinical treatment of the PD.

关键词： levodopa brain delivery cerebral lymphatic vasculature Parkinson’s disease

Nutritional Status, Food Consumption at Home, and Preference-Selection in the School

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Food and Nutrition Sciences 2012年第3期3卷 281-285页

作者： María del Refugio lópez-Gamino Martha Elba Alarcón-Armendáriz Xochitl Karina torres-Beltrán Educación para la Salud FES IztacalaUniversidad Nacional Autónoma de MéxicoMéxico CityMéxico.

To assess the relationship between food consumption at home, nutritional status, gender preference and the preference-selection of natural products (fruits and vegetables) and industrialized (candies and chips) in a situation of free access for a population of Mexican schoolchildren. 115 children participated in the test, 59 boys and 56 girls from second, fourth and sixth grade of elementary school. We have taken measures of weight, size and the 24-hour consumption record during over five days, at which time also we evaluated the preference and selection of a group of ten products (naturals and industrialized). According to the results 60% of children had normal weight, 23.47% overweight, 14.8% risk of overweight an 1.73% underweight. There were no significant differences with X2 test between nutritional status and gender. Multivariate analysis was applied between gender, consumption by food groups and nutritional status, the interaction was significant in all cases. The Pearson correlation between preference and food choice in the situation of open access is high in the school students at risk of overweight. The preferred and selected products for consumption are those with the highest content of saturated fat, sugars and salt, the less preferred and selected products were fruits and vegetables. We could conclude that the population is at risk for their low consumption of fruits and vegetables;situation that is reflection of the home consumption this document.

关键词： Food Preferences Diet Schoolchild Nutritional Status

Non-invasive diagnosis of gastric mucosal atrophy in an asymptomatic population with high prevalence of gastric cancer

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World Journal of Gastroenterology 2006年第44期12卷 7172-7178页

作者： Antonio Rollan Catterina Ferreccio Alessandra Gederlini Carolina Serrano Javiera torres Paul Harris Department of Gastroenterology Faculty ofMedicine Pontificia Universidad Católica de Chile Marcoleta367 Santiago 6510260 Chile Department of Public Health Faculty of Medicine Pontificia Universidad Católica de Chile Marcoleta 367 Santiago 6510260 Chile Department of Pediatrics Faculty of Medicine Pontificia Universidad Católica de Chile Marcoleta 367 Santiago 6510260 Chile Department of Pathology Faculty of Medicine Pontificia Universidad Católica de Chile Marcoleta 367 Santiago 6510260 Chile

AIM: To validate a non-invasive method to detect gastric mucosal atrophy in a Chilean population with high prevalence of gastric cancer and a poor survival rate. METHODS: We first determined the optimal cut-off level of serum pepsinogen (PG)-1, PG-1/PG-2 ratio and 17-gastrin in 31 voluntary symptomatic patients (mean age: 66.1 years), of them 61% had histologically confirmed gastric atrophy. Then, in a population-based sample of 536 healthy individuals (209 residents in counties with higher relative risk and 327 residents in counties with lower relative risk for gastric cancer), we measured serum anti-H pylori antibodies, PG and 17-gastrin and estimated their risk of gastric cancer. RESUlTS: We found that serum PG-1 l, PG-1/PG-2 ratio 13.3 pmol/l had a high specificity (91%-100%) and a fair sensitivity (56%-78%) to detect corpus-predominant atrophy. Based on low serum PG-1 and PG-1/PG-2 ratio together as diagnostic criteria, 12.5% of the asymptomatic subjects had corpus-predominant atrophy (0% of those under 25 years and 20.2% over 65 years old). The frequency of gastric atrophy was similar (12% vs 13%) but H pylori infection rate was slightly higher (77% vs 71%) in the high-risk compared to the low-risk counties. Based on their estimated gastric cancer risk, individuals were classified as: low-risk group (no H pylori infection and no atrophy; n = 115; 21.4%); moderate-risk group(H pylori infection but no atrophy; n = 354, 66.0%); and high-risk group (gastric atrophy, with or without H pylori infection; n = 67, 12.5%). The high-risk group was significantly older (mean age: 61.9 ± 13.3 years), more frequently men and less educated as compared with the low-risk group. CONClUSION: We propose to concentrate on an upper gastrointestinal endoscopy for detection of early gastric cancer in the high-risk group. This intervention model could improve the poor prognosis of gastric cancer in Chile.

关键词： Gastric cancer H pylori Gastric atrophy Non-invasive diagnosis Pepsinogen Gastrin

Rough Sets for Human Resource Competence Evaluation and Experiences

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Applied Mathematics 2016年第12期7卷 1317-1325页

作者： Surayne torres lópez Gilberto Fernando Castro Aguilar Iliana Pérez Pupo Pedro Piñero Pérez laynier Piedra Diéguez laboratorio de Investigaciones en Gestión de Proyectos Facultad 5 Universidad de las Ciencias Informáticas La Habana Cuba Facultad de Ingeniería Universidad de Guayaquil Guayaquil Ecuador Centro de Informática Industrial Universidad de las Ciencias Informáticas La Habana Cuba

The evaluation of labor competences is an important activity for proper management of human resources. To assess labor competences, different techniques have been proposed, but these proposals represent invasive mechanisms so that its implementation affects the efficiency of the project, and do not store the experiences for further processing. The aim of this paper is to propose two alternative algorithms to recover the evidences of performance of human resources by identifying their relationship with labor competences, using rough sets and text distance. The experimental application of the algorithms demonstrated efficiency levels in line with the human evaluators and efficiency improvement in the evaluation process, compared with methods like 360 degrees.

关键词： Rough Sets Human Resource Competences Cosine Distance

RANS simulations of the U and V grooves effect in the subcritical flow over four rotated circular cylinders

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Journal of Hydrodynamics 2015年第4期27卷 569-578页

作者： AlONZO-GARCIA A. GUTIERREZ-torres C.del C. JIMENEZ BERNAl J.A. MOllINEDO-PONCE de lEON H.R. MARTINEZ-DElGADIllO S.A. BARBOSA-SAlDANA J.G. Instituto Politécnico Nacional SEPI ESIME ZacatencoLABINTHAP U.P.Adolfo López Mateos Edif.5 3er.PisoMéxicoD.F.México Instituto Politécnico Nacional UPIITAAv.IPN 2580C.P.07340MéxicoD.F.México Universidad Autónoma Metropolitana-Azcapotzalco Depto.Ciencias BásicasAv.San Pablo 180Azcapotzalco C.P 07740MéxicoD.F.México

This paper presents a CFD study about the effect of the V and U grooves in the flow over four cylinders in diamond shape configuration at subcritical flow conditions（Re= 41 000）. The k- ε Realizable turbulence model was implemented to fully structured hexahedral grids with near-wall refinements. Results showed that the numerical model was able to reproduce the impinging flow pattern and the repulsive forces present in the lateral cylinders of the smooth cylinder array. As a consequence of the flow alignment induced by the grooves, a jet-flow is formed between the lateral cylinders, which could cause an important vortex induced vibration effect especially in the rear cylinder. The magnitudes of the shear stresses at the valleys and peaks for the V grooved cylinders were lower than those of the U grooved cylinders, but the separation points were delayed due the U grooves presence. It is discussed the presence of a blowing effect caused by counter-rotating eddies located near the grooves peaks that cause a decrease of the shear stresses in the valleys, and promote them at the peaks.

关键词： RANS model grooved cylinder four cylinders subcritical flow impinging flow

应用固相萃取高效液相色谱-质谱法测定水中多种农药残留

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农业环境科学学报 2006年第B09期25卷 755-758页

作者：申义珍 J.l.Martinez Vidal R.Romero Gonealez M.E.Hernandez torres 扬州市农业环境监测站江苏扬州225002 University of Almeria Spain

应用HlB固相萃取高效液相色谱-质谱法同时测定水中杀虫剂、杀菌剂、除草剂、杀螨剂、杀线虫剂等5类30种农药残留,标准曲线决定系数r2均大于0.99,标准添加回收率达76%￣107%,平均为87.9%。在实际测定的10个水样中,有个水样的杀铃脲(Trifl... 详细信息

应用HlB固相萃取高效液相色谱-质谱法同时测定水中杀虫剂、杀菌剂、除草剂、杀螨剂、杀线虫剂等5类30种农药残留,标准曲线决定系数r2均大于0.99,标准添加回收率达76%￣107%,平均为87.9%。在实际测定的10个水样中,有个水样的杀铃脲(Triflumuron)含量超标。

关键词：农药液相色谱质谱水固相萃取