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As Regards the Speed in a Medium of the Electromagnetic Radiation Field

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Journal of Modern Physics 2016年第11期7卷 1320-1330页

作者： Robert M. Yamaleev A. R. Rodríguez-domínguez Joint Institute for Nuclear Research Dubna Russia Instituto de Física Universidad Autónoma de San Luis Potosí San Luis Potosí México

The velocity of the electromagnetic radiation in a perfect dielectric, containing no charges and no conduction currents, is explored and determined on making use of the Lorentz transformations. Besides the idealised blackbody radiation, whose vacuum propagation velocity is the universal constant c, being this value independent of the observer, there is another behaviour of electromagnetic radiation, we call inertial radiation, which is characterized by an electromagnetic inertial density , and therefore, it happens to be described by a time-like Poynting four-vector field which propagates with velocity . is found to be a relativistic invariant expressible in terms of the relativistic invariants of the electromagnetic field. It is shown that there is a rest frame, where the Poynting vector is equal to zero. Both phase and group velocities of the electromagnetic radiation are evaluated. The wave and eikonal equations for the dynamics of the radiation field are formulated.

关键词： Inertial Radiation Field Mass Field Density Rest State Poynting Vector Wave and Eikonal Equations of the Radiation Field Dynamics

Management of Crohn’s disease in smokers:Is an alternative approach necessary?

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World Journal of Gastroenterology 2011年第31期17卷 3567-3574页

作者： Pilar Nos Eugeni domènech Gastroenterology Unit La Fe University Hospital Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas(CI-BEREHD) MadridSpain Digestive Disease Department Germans Trias i Pujol Hospital

Inflammatory bowel disease(IBD) is a chronic condition with a pathogenic background that involves both genetic and environmental *** important progress has been made regarding the former in the last decade,scarce knowledge is available for the *** this sense,smoking remains the most important environmental factor in *** smoking increases the risk of developing Crohn's disease(CD).Moreover,CD patients who start or continue smoking after disease diagnosis are at risk for poorer outcomes such as higher therapeutic requirements and disease-related complications,as compared to those patients who quit smoking or who never ***,the harmful effect of active smoking is not uniform in all patients or in all clinical *** designed to facilitate smoking cessation may impact the course of the *** this article,the available evidence of the deleterious effects of smoking on CD is reviewed in detail,and alternative therapeutic approaches to CD in smokers are proposed.

关键词： Tobacco Crohn's disease Therapy Smoking cessation Recurrence Complications

Autolytic and Proteolytic Properties of Strains of<i>Lactococcus lactis</i>Isolated from Different Vegetables, Raw-Milk Cheeses and Commercial Starter Cultures

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Food and Nutrition Sciences 2013年第11期4卷 21-26页

作者： Carolina Nájera-domínguez Nestor Gutiérrez-Méndez Chemistry Faculty University Autonomous of Chihuahua Chihuahua Mexico.

The autolysis and proteolysis are important features in the strains of L. lactis used in the manufacture of cheese. The autolytic and proteolytic activity of L. lactis has been linked with the development of flavor and texture in the cheese. On the other hand, there is a growing interest in new strains isolated from raw-milk cheeses and vegetables. These wild-strains have showed different features of industrial importance in comparison with those observed in commercial cultures. However, it still not clear if the autolytic and proteolytic properties of these wild-strains differ from the industrial strains. The objective of this work was to assess the autolytic and proteolytic activities of 21 strains of L. lactis isolated from diverse sources. The rates of autolysis and proteolysis observed in vitro were highly strain-dependent. The pH and the NaCl concentration in the media affected significantly the autolysis of L. lactis. The strains isolated from vegetable showed in general low and medium autolytic activity, whereas the strains isolated from raw-milk cheeses had medium to high autolytic activity. The strain with highest proteolytic activity was a strain isolated from corn leaves. Although still not clear how this strain acquired this pronounced characteristic.

关键词： Com Autolysis Proteolysis L. lactis Wild-Strains

Whole lesion histogram analysis of apparent diffusion coefficient predicts therapy response in locally advanced rectal cancer

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World Journal of Gastroenterology 2022年第23期28卷 2609-2624页

作者： Mayra Evelia Jiménez de los Santos Juan Armando Reyes-Pérez Victor domínguez Osorio Yolanda Villaseñor-Navarro Liliana Moreno-Astudillo Itzel Vela-Sarmiento Isabel Sollozo-Dupont Department of Radiology National Cancer InstituteMexico 14080Mexico Department of Gastrointestinal Surgery National Cancer InstituteMexico 14080Mexico

BACKGROUND Whole-tumor apparent diffusion coefficient(ADC)histogram analysis is relevant to predicting the neoadjuvant chemoradiation therapy(nCRT)response in patients with locally advanced rectal cancer(LARC).AIM To evaluate the performance of ADC histogram-derived parameters for predicting the outcomes of patients with *** This is a single-center,retrospective study,which included 48 patients with *** patients underwent a pre-treatment magnetic resonance imaging(MRI)scan for primary tumor staging and a second restaging MRI for response *** sample was distributed as follows:18 responder patients(R)and 30 non-responders(non-R).Eight parameters derived from the whole-lesion histogram analysis(ADCmean,skewness,kurtosis,and ADC10^(th),25^(th),50^(th),75^(th),90^(th) percentiles),as well as the ADCmean from the hot spot region of interest(ROI),were calculated for each patient before and after *** all data were compared between R and non-R using the Mann-Whitney U *** measures of diagnostic accuracy were applied:the receiver operating characteristic curve and the diagnostic odds ratio(DOR).We also reported intra-and interobserver variability by calculating the intraclass correlation coefficient(ICC).RESULTS Post-nCRT kurtosis,as well as post-nCRT skewness,were significantly lower in R than in non-R(both P<0.001,respectively).We also found that,after treatment,R had a larger loss of both kurtosis and skewness than non-R(Δ%kurtosis and Δ skewness,P<0.001).Other parameters that demonstrated changes between groups were post-nCRT ADC10^(th),Δ%ADC10^(th),Δ%ADCmean,and ROIΔ%***,the best diagnostic performance was achieved byΔ%kurtosis at a threshold of 11.85%(Area under the receiver operating characteristic curve[AUC]=0.991,DOR=376),followed by post-nCRT kurtosis=0.78×10^(-3)mm^(2)/s(AUC=0.985,DOR=375.3),Δskewness=0.16(AUC=0.885,DOR=192.2)and post-nCRT skewness=1.59×10^(-3)mm^(2)/s(AUC=0.815,DOR=168.6).Finally,intraclass corr

关键词： Apparent diffusion coefficient Diffusion-weighted imaging Histogram analysis Magnetic resonance imaging Locally advanced rectal cancer

Epidemiological assessment of intestinal parasitic infections in dogs at animal shelter in Veracruz,Mexico

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Asian Pacific Journal of Tropical Biomedicine 2015年第1期5卷 34-39页

作者： Cosme Alvarado-Esquivel Dora Romero-Salas Mariel Aguilar-domínguez Anabel Cruz-Romero Nelly Ibarra-Priego dalberto Angel Pérez-de-Len Biomedical Research Laboratory School of Medicine and NutritionJuarez University of the State of DurangoAvenida Universidad S/N34000 DurangoMexico Parasitology Laboratory School of Veterinary Medicine and ZootechnicsUniversidad VeracruzanaCircunvalacin y Yez S/N91710 VeracruzMexico United States Department of Agriculture Agricultural Research ServiceKnipling-Bushland U.S. Livestock Insects Research Laboratory

Objective:To determine the prevalence of infection with intestinal parasites in 101 dogs in an animal shelter in ***,and investigate whether any general characteristics of the dogs were associated with ***:Parasitologiesl examination of fecal samples from the dogs was performed by means of centrifuge-flotation using Sheather's sucrose and zinc sulfate flotation *** addition,hematocrit was determined in each canine blood ***:Intestinal parasites were found in 99(98.0%) of the 101 dogs *** five different intestinal parasites were identified:Ancylostoma caninum in 89 dogs(88.1%).Giardia canis in 46(45.5%).Unciiuiria stenocephalia in 43(42.6%).Trichuris vulpis in 19(18.8%)and Strongyloides canis in 16(15.8%).Multivariate analysis showed:I) Giardia infection was associated with young age and mixed breed;2) Ancylostoma was associated with young age and no rabies vaccination:and 3) Strongyloides was associated with no rabies *** and Trichuris infections were not associated with the variables ***:A high prevalence of intestinal parasites was found in the dogs *** suggests that the environment is highly contaminated with intestinal *** and therapeutic measures should be taken against infection with intestinal parasites in dogs in this region.

关键词： Intestinal parasites Infection Prevalence Shelter Dogs Mexico

Graphene Oxide/Multilayer-Graphene Synthesized from Electrochemically Exfoliated Graphite and Its Influence on Mechanical Behavior of Polyurethane Composites

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Materials Sciences and Applications 2018年第7期9卷 565-575页

作者： L. M. Flores-Vélez O. domínguez Faculty of Chemistry UASLP San Luis Potosí México Institute of Metallurgy UASLP San Luis Potosí México

Graphene Oxide/Multilayer-Graphene (GO-MG) flakes were obtained using an electrochemically exfoliated graphite (GR) electrode from secondary steel-making industry performed in a two-electrode system using tungsten as the counter electrode and GR as the working electrode. The exfoliated GO-MG flakes were processed and incorporated in an elastomeric polyurethane (PU) matrix. The mechanical properties of the PU/GO-MG composites were evaluated and compared with equivalent composites made of PU/GR powder. From experimental data analysis it was concluded that GO-MG flakes were approximately composed of 67 wt% GO and 33 wt% MG. The number of layers in the graphene flakes was estimated to be between 2 and 5 sheets. PU showed a breaking stress of 570 kPa, while the PU/20wt% GR attained a maximum stress of 750 kPa as compared to PU/10wt% GO-MF composite exhibiting a breaking stress of 1060 kPa.

关键词： Electrochemical Exfoliation Graphene Oxide Nanocomposites Polyurethane

Mismatch repair protein expression and intratumoral budding in rectal cancer are associated with an increased pathological complete response to preoperative chemoradiotherapy: A case-control study

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World Journal of Clinical Oncology 2018年第7期9卷 133-139页

作者： Leonardo S Lino-Silva Armando Gamboa-domínguez Diego Zú?iga-Tamayo Rosa A Salcedo-Hernández Lucely Cetina David Cantú-de-León Surgical Pathology Instituto Nacional de Cancerología Surgical Pathology Instituto Nacional de ciencias Médicas y Nutrición salvador Zubirán Surgical Oncology Instituto Nacional de Cancerología Medical Oncology Instituto Nacional de Cancerología

AIM To determine whether the association of rectal adenocarcinoma with a defective-mismatch repair system(dMMR) was associated with a pathological complete response(pCR) to preoperative *** A case-control study was designed with the aim of determining if patients with rectal adenocarcinoma with dM MR had an associated high pCR rate in response to neoadjuvant chemoradiotherapy(nCRT).RESULTS Seventy-two cases with pCR were compared against 144 controls without pCR. Across 216 cases, the mean age was 56.8 years, 140(64.8%) were men, and 63(29.2%) demonstrated the dMMR system. The pCR was associated with G1 tumors, dMMR, the absence of vascular invasion, and low tumor budding in the pretreatment biopsy. In a multivariant analysis, the factors associated with pCR were dMMR(OR: 2.61; 95%CI: 1.355-5.040, P = 0.004) and a low degree of tumor budding(OR: 2.52; 95%CI: 1.366-4.894, P = 0.025).CONCLUSION We found an independent association between dMMR and a low rate of tumor budding, with a higher rate of pCR, in the basal biopsies of patients with rectal carcinoma subjected to nCRT.

关键词： Rectal cancer Chemoradiotherapy Tumor budding Mismatch repair Pathological complete response

Ultrasonic Fatigue Endurance Investigation on Plastic Material Nylon 6

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Materials Sciences and Applications 2011年第9期2卷 1293-1297页

作者： Gonzalo M. domínguez Almaraz Erasmo Correa Gómez 不详

Ultrasonic fatigue tests were carried out on the plastic material Nylon 6. Special attention was devoted to the temperature control in order to avoid physic-chemical transformation of this low melting point material. Under ultrasonic fatigue tests, important heat dissipation takes place at the narrow section of hourglass shape specimen leading to high temperature at this zone. The specimen was calculated to meet the resonance condition with the smallest dimensions at its narrow section, with aim to reduce the temperature gradient at this zone of this non heat conducting material. Temperature at narrow section was maintained lower than 45℃ using a cooling system with cooling air;under this condi- tion the ultrasonic fatigue tests were performed. Experimental tests were carried out at low loading range (9 - 12.5% of the elastic limit of material) in order to control the highest temperature and to avoid that specimen was out of resonance condition. Experimental results are analyzed together with the fracture surfaces and conclusions are presented concerning the ultrasonic fatigue endurance of this polymeric material.

关键词： Ultrasonic Fatigue Tests Polymeric Material Numerical Simulation Temperature Control Fatigue Life Fracture Surface

Predictive value of bleeding risk scores in elderly patients with atrial fibrillation and oral anticoagulation

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老年心脏病学杂志:英文版 2023年第9期20卷 684-692页

作者： Pablo domínguez-Erquicia Sergio Raposeiras-Roubín Emad Abu-Assi Andrea Lizancos-Castro Jose A Parada-Barcia AndréGonzález-García Ana Ledo-Piñeiro Vanesa Noriega-Caro Carla Iglesias-Otero AndrésÍñiguez-Romo Department of Cardiology University HospitalÁlvaro CunqueiroVigoSpain Health Research Institute Galicia Sur VigoSpain

BACKGROUND The predictive value of bleeding risk scores for atrial fibrillation in older patients is not as well *** goal of this study was to evaluate the predictive value of HASBLED,ORBIT and ATRIA for major bleeding(MB)and intracranial hemorrhage(ICH)in patients≥75 years with atrial fibrillation and oral anticoagulation(OAC).METHODS A retrospective unicenter study including patients≥75 years with atrial fibrillation(AF)and OAC.A total of 7613 patients≥75 years with AF and OAC included between 2014 and 2018(registry:NCT04364516).We analyzed the discriminative value of HASBLED,ATRIA and ORBIT scores for bleeding endpoints(major bleeding as primary endpoint and intracerebral hemorrhage as secondary).Cox regression was used to predict major bleeding with each scale and also for searching other variables potentially predictor of major *** discrimination was assessed using Harrell’s *** was assessed with goodness-of-fit test proposed by Gronnesby and *** During a mean follow up of 4.0 years(IQR:2.4–5.7 years),729 patients developed MB(2.61 per 100 patients/year)and 243 patients developed ICH(0.85 per 100 patients/year).Three scores showed a low discrimination for major bleeding,being ORBIT the best(HASBLED C statistic=0.557;ATRIA C statistic=0.568;ORBIT C statistic=0.595)and also a low discrimination for ICH(HASBLED C statistic=0.509;ATRIA C statistic=0.522;ORBIT C statistic=0.526).Among the variables that are part of the scores and other baseline characteristics,after multivariable adjustment only sex(male),dementia,prior admission for bleeding,anemia and liver disease were found as a predictors of *** In older patients under oral anticoagulation with atrial fibrillation,the risk scores HASBLED,ATRIA and ORBIT showed a weak discrimination for major bleeding and intracranial ***,other better alternatives should be evaluated for this purpose.

关键词： patients bleeding fibrillation