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Foaming supramolecular surfactants for gas mobility control in naturally fractured carbonate reservoirs at high temperature,salinity,and hardness

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Petroleum Science 2022年第6期19卷 3134-3148页

作者： Enrique Soto-Castruita raúl Hern andez-Altamirano Eduardo Buenrostro-González Erick-Emanuel Luna-Rojero Sung Jae Ko-Kim Violeta-Yasmín Mena-Cervantes Mirna Pons-jim.nez Jorge-Francisco ramírez-Pérez David-Aaσn Nieto-Alvarez Ricardo Cerón-Camacho Jos e-Ernesto Parra raúl Oviedo-Roa Jos e-Manuel Martínez-Magadán Rodolfo Cisneros-Dévora Luis-S.Zamudio-Rivera Instituto Mexicano del Petr oleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico CONACy T-Instituto Mexicano del Petroleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico Centro Mexicano para la Produccion mas Limpia Instituto Politecnico NacionalAvenida Acueducto s/nCol.La Laguna TicomanCiudad de Mexico07340Mexico Centro de Tecnologías para Exploracion y Produccion Camino de Terracería 800Col.San Jose NovilleroBoca delRíoVeracruz94286Mexico

Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on ***,they present early water and gas channeling but could be remediated by using foaming agents to control these phenomena through blocking channeling *** Mexico these reservoirs have pressure up to 5,500 psi,high temperature up to 200℃,salinity up to400,000 ppm,and hardness up to 250,000 ppm;due to these thermodynamic conditions,there has been no available technology to form stable enough *** this work,a foaming supramolecular surfactant with the capability to chelate Ca^(2+)ions is *** a result,surfactant monomers are bridged by captured Ca^(2+)cations leading to the formation of high-molecular-weight oligomers,which significantly increment the viscosity of the solution improving the foam stability,and since at this manner the Ca2+cations are no longer available to precipitate as components of solid salts,the foaming supramolecular surfactant also performs as *** observations are explained through quantum theoretical *** foam is stable,effectively blocking the gas channels,whereas in presence of oil the foam is broken leading the oil to pass into the *** characteristic rheological properties of the foam allow its injection into the formation at a range of flow rates,foam qualities,and shear stress to achieve the flooding and the blocking of a variety of fractured carbonate formations,and the change of the wettability of the matrix,which is a desirable behavior in a huff and puff process,as reported in a previous publication about a successful pilot test of this foam.

关键词： Calcium chelation Foaming composition Supramolecular surfactant Molecular design Gas mobility control Flow assurance Improved oil recovery Conformance control

Growth plasticity of conifers did not avoid declining resilience to soil and atmospheric droughts during the 20th century

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Forest Ecosystems 2023年第2期10卷 238-251页

作者： Tong Zheng Jordi Martínez-Vilalta raúl García-Valdés Antonio Gazol J.Julio Camarero Changcheng Mu Maurizio Mencuccini Northeast Forestry University Harbin150040China CREAF E08193 Bellaterra(Cerdanyola del Vallès)CataloniaSpain Universitat Autònoma de Barcelona E08193 Bellaterra(Cerdanyola del Vallès)CataloniaSpain Centre de Ciència i Tecnologia Forestal de Catalunya(CTFC) E-25280SolsonaSpain Department of Biology GeologyPhysics and Inorganic ChemistryRey Juan Carlos University28933MóstolesMadridSpain Instituto Pirenaico de Ecologia(IPE-CSIC) Zaragoza50059Spain ICREA 08010BarcelonaSpain

Background:Plasticity in response to environmental drivers can help trees cope with ***,our understanding of the importance of plasticity and physiological adjustments in trees under global change is ***:We used the International Tree-Ring Data Bank(ITRDB)to examine 20th century growth responses in conifer trees during(resistance)and following(resilience)years of severe soil and atmospheric droughts occurring in isolation or as compound *** resilience indices were calculated using observed growth divided by expected growth to avoid spurious correlations,in which the expected values were obtained by the autoregressive moving average(ARIMA)*** used high atmospheric vapour pressure deficit(VPD)to select years of atmospheric drought and low annual values of the Standardized Precipitation-Evapotranspiration Index(SPEI)to select years with soil *** acquired the sensitivities(i.e.,the slopes of the relationships)by fitting the resilience indices as a function of environmental drivers,and assessed how these sensitivities changed over time for different types of drought events using linear mixed *** also checked whether plasticity in growth responses was sufficient to prevent long-term trends of growth reductions during or after severe *** acknowledge that by focusing on the response of surviving trees from the ITRDB we are potentially biasing our results towards higher resilience,as stand level responses(e.g.,mortality)may result in lowered competition after the disturbance ***:Sensitivities of resilience to VPD and SPEI changed throughout the 20th century,with the directions of these changes often reversing in the second half of the *** the 1961–2010 period,changing sensitivities had positive effects on resilience,especially following years of high-VPD and compound events,avoiding growth losses that would have occurred if sensitivities had remained *** sensitivity changes,resilience

关键词： Tree rings Growth Drought Vapor pressure deficit Plasticity Acclimation

Inflammatory bowel disease: A descriptive study of 716 local Chilean patients

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World Journal of Gastroenterology 2016年第22期22卷 5267-5275页

作者： Daniela Simian Daniela Fluxá Lilian Flores Jaime Lubascher Patricio Ibánez Carolina Figueroa Udo Kronberg raúl Acuna Mauricio Moreno Rodrigo Quera Academic Research Unit Clinica Las Condes Santiago 7591046 Chile Gastroenterology Departament Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Gastroenterology Department Clinica Las Condes Santiago 7591046 Chile Inflammatory Bowel Disease Program Colorectal Surgery Department Clinica Las Condes Santiago 7591046 Chile Laboratory of Oncology and Molecular Genetics Colorectal Surgery Clinica Las Condes Santiago 7591046 Chile

AIM: To demographically and clinically characterize inflammatory bowel disease (IBD) from the local registry and update data previously published by our ***: A descriptive study of a cohort based on a registry of patients aged 15 years or older who were diagnosed with IBD and attended the IBD program at Clínica Las Condes in Santiago, Chile. The registry was created in April 2012 and includes patients registered up to October 2015. The information was anonymously downloaded in a monthly report, and the information on patients with more than one visit was updated. The registry includes demographic, clinical and disease characteristics, including the Montreal Classification, medical treatment, surgeries and hospitalizations for crisis. Data regarding infection with Clostridium difficile (C. difficile) were incorporated in the registry in 2014. Data for patients who received consultations as second opinions and continued treatment at this institution were also ***: The study included 716 patients with IBD: 508 patients (71%) were diagnosed with ulcerative colitis (UC), 196 patients (27%) were diagnosed with Crohn’s disease (CD) and 12 patients (2%) were diagnosed with unclassifiable IBD. The UC/CD ratio was 2.6/1. The median age was 36 years (range 16-88), and 58% of the patients were female, with a median age at diagnosis of 29 years (range 5-76). In the past 15 years, a sustained increase in the number of patients diagnosed with IBD was observed, where 87% of the patients were diagnosed between the years 2001 and 2015. In the cohort examined in the present study, extensive colitis (50%) and colonic involvement (44%) predominated in the patients with UC and CD, respectively. In CD patients, non-stricturing/non-penetrating behavior was more frequent (80%), and perianal disease was observed in 28% of the patients. There were significant differences in treatment between UC and CD, with a higher use of corticosteroids, and immunosupp

关键词： Inflammatory bowel disease Crohn’ s disease Ulcerative colitis South America Latin America Chile Epidemiology

Treatment of chronic hepatitis C with direct-acting antivirals: The role of resistance

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World Journal of Gastroenterology 2016年第29期22卷 6573-6581页

作者： Miguel jim.nez-Pérez Rocío González-Grande Pilar Espana Contreras Isabel Pinazo Martínez Jesús de la Cruz Lombardo raúl Olmedo Martín UGC de Aparato Digestivo Unidad de Hepatologia-Trasplante Hepatico Hospital Universitario Regional de Malaga 29010 Malaga Spain Liver transplantation and hepatology unit UGC de Aparato Digestivo Hospital Regional Universitario 29010 Malaga Spain

The use of direct-acting antivirals(DAAs) to treat chronic hepatitis C has resulted in a significant increase in rates of sustained viral response(around 90%-95%) as compared with the standard treatment of peginterferon/ribavirin. Despite this, however, the rates of therapeutic failure in daily clinical practice range from 10%-15%. Most of these cases are due to the presence of resistant viral variants, resulting from mutations produced by substitutions of amino acids in the viral target protein that reduce viral sensitivity to DAAs, thus limiting the efficacy of these drugs. The high genetic diversity of hepatitis C virus has resulted in the existence of resistance-associated variants(raVs), sometimes even before starting treatment with DAAs, though generally at low levels. These preexisting raVs do not appear to impact on the sustained viral response, whereas those that appear after DAA therapy could well be determinant in virological failure with future treatments. As well as the presence of raVs, virological failure to treatment with DAAs is generally associated with other factors related with a poor response, such as the degree of fibrosis, the response to previous therapy, the viral load or the viral genotype. Nonetheless, viral breakthrough and relapse can still occur in the absence of detectable raVs and after the use of highly effective DAAs, so that the true clinical impact of the presence of raVs in therapeutic failure remains to be determined.

关键词： Direct-acting antivirals Resistance Treatment Hepatitis C virus

The Drying of Pyridine Hydrobromide

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Chinese Journal of Chemical Engineering 1998年第2期6卷 76-80页

作者： RenéD.Peralta Rodríguez raúl G.López Campos Jaime Wisniak Jacinto G.Rodríguez Gómez Silvia Torres Rincón M.Esther Treviño Martínez Centro de Investigacion en Quimica Aplicada Blvd.Ing.Enrique Reyna Hermosillo No.140C.P.25100SaltilloCoahuilaMexico Department of Chemical Engineering Ben-Gurion University of the NegevBeer-ShevaIsrael

1 INTRODUCTIONThe drying of fine chemicals and pharmaceuticals is dominated by a number of special factorscompared to the drying of bulk *** include:very high value of product;lowthroughputs(typically,100 kg·h-1);materials that frequently possess toxic properties andare often sticky,pasty and difficult to handle when wet;the moisture to be evaporated ofteninvolves solvents;and multipurpose processing plants.

关键词： drying pyridine hydrobromide

Genomic Organization of Purinergic P2X Receptors

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Pharmacology & Pharmacy 2015年第8期6卷 341-362页

作者： raúl Loera-Valencia Josué Obed Jaramillo-Polanco Andrómeda Linan-Rico María Guadalupe Nieto Pescador Juan Francisco jim.nez Bremont Carlos Barajas-López División de Biología Molecular Instituto Potosino de Investigación Científica y Tecnológica San Luís Potosí México

Purinergic P2X receptors are a family of ligand-gated cationic channels activated by extracellular ATP. P2X subunit protein sequences are highly conserved between vertebrate species. However, they can generate a great diversity of coding splicing variants to fulfill several roles in mammalian physiology. Despite intensive research in P2X expression in both central and peripheral nervous system, there is little information about their homology, genomic structure and other key features that can help to develop selective drugs or regulatory strategies of pharmacological value which are lacking today. In order to obtain clues on mammalian P2X diversity, we have performed a bioinformatics analysis of the coding regions and introns of the seven P2X subunits present in human, simian, dog, mouse, rat and zebrafish. Here we report the arrangements of exon and intron sequences, considering its number, size, phase and placement;proposing some ideas about the gain and loss of exons and retention of introns. Taken together, these evidences show traits that can be used to gain insight into the evolutionary history of vertebrate P2X receptors and better understand the diversity of subunits coding the purinergic signaling in mammals.

关键词： Alternative Splicing Intron Genomic Organization P2X Purinergic Signalling

A Check List to Reduce Misuse of Primary Cesarean Sections in Women with a Single Fetus in Cephalic Position

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Health 2017年第8期9卷 1251-1263页

作者： Catalina Acuna Pradilla Delgzar raúl Gómez Pereira Luis Alfonso Díaz-Martínez Gyneco Obstetrics Department School of MedicineFaculty of HealthUniversidad Industrial de SantanderBucaramangaColombia School of Medicine Faculty of HealthUniversidad Industrial de SantanderBucaramangaColombia

Background: Avoiding primary C-section is the safest and most effective way of decreasing C-section rates. We analyzed circumstances and decisions made among pregnant women without history of C-section and cephalic single fetus (group B), who ended up having a Cesarean birth, to identify opportunities that may optimize the decisions about delivery. Methodology: We evaluated the clinical histories of pregnant women from group B who completed their pregnancies in the Hospital Universitario de Santander (Bucaramanga, Colombia) during 2013. We evaluated the decision moments from admission until birth, including the registry of the reasons for having a C-section, compliance of all the criteria to support the decision and its appropriateness, and how adequate were the procedures done during the induction or augmentation of labor. Results: We evaluated 1320 histories;666 (55.7%) ended by C-Section. In 59.8% of the histories, we identified at least one decision that could have been addressed differently to optimize the delivery type and, potentially, avoid ending in a Cesarean birth. The most frequent opportunities arise due to a lack of clarity in the record of the reason for performing the C-section (70.1%), and inadequate use of labor induction in the patients that had to end their gestation (38.5%). Conclusion: In the Hospital Universitario de Santander during 2013, despite observing a meaningful subregistry of the indication to perform a C-section, we found that in one out of every two patients there are opportunities of improvement in the registry and attention to reduce the high incidence of C-sections in the institution. This analysis allowed us to create a checklist to fill out before making the final decision of performing a Cesarean birth.

关键词： Labor Delivery Type Cesarean Birth

Percutaneous Ultrasound-Guided radiofrequency Thermal Ablation for Treatment of Uterine Fibroids

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Open Journal of Obstetrics and Gynecology 2014年第12期4卷 716-724页

作者： raúl García Marcos Javier Monleón Alicia Martínez-Varea Fernando Gómez Guillermina Montoliú Jose J. Martínez Luis Martí-Bonmatí Antonio Pellicer Department Obstetrics and Gynecology La Fe University Hospital Valencia Spain Department of radiology Hospital Clinic Barcelona Spain Department of radiology La Fe University Hospital Valencia Spain

Purpose: To assess the safety, efficacy and effectiveness of percutaneous radiofrequency (RF) thermal ablation to reduce symptoms of uterine fibroids. Materials and Methods: 17 premenopausal women with symptomatic uterine fibroids despite conventional medical treatment were included. The assessment of symptoms and characteristics of fibroids by vaginal ultrasound, magnetic resonance imaging (MRI) and contrast enhanced ultrasound (CEUS) was performed before starting treatment and 6 months after the procedure. Successful treatment was clinically considered if patients reported a reduction in symptoms 6 months after RF myolysis. Successful treatment was also considered if the necrosis of the fibroid was greater than 50%, 6 months after treatment. Results: The baseline score on visual analogue scale (VAS) for dysmenorrhea and intermenstrual pain was 5.76 ± 3.31 and 3.0 ± 3.4, respectively. According to a score of 0 - 3, baseline bleeding during menstruation was 2.29 ± 0.92. Six months after RF myolysis, the VAS for dysmenorrhea was 2.75 ± 3.32 (p = 0.004), whereas for intermenstrual pain it was 1.38 ± 2.56 (p = 0.02). Menstrual bleeding was reduced to 1.13 ± 0.89 (p = 0.005). Clinical success of the treatment was evident in 11 (64.7%) of the 17 patients with a 95% CI [38.6%, 84.7%]. Fourteen patients underwent MRI monitoring 6 months post-myolysis. Compared to baseline fibroid volume, ultrasound and MRI volume were 57.38% and 79.66% six months after surgery, respectively. A total of 13 patients (92.86%) had radiological success from the treatment (95% CI [64.2%, 99.6%]). Conclusion: Since percutaneous RF myolysis reduces volume and symptoms of uterine fibroids, it may be considered as a valid treatment for symptomatic fibroids.

关键词： Percutaneous radiofrequency Thermal Ablation Myolysis Uterine Fibroids

Sub-assemblages distribution of Giardia duodenalis and its association with clinical symptoms in children from Sancti Spíritus,Cuba

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Journal of Coastal Life Medicine 2015年第11期 864-868页

作者： Luis Jerez Puebla Fidel ANúnez Alexey Brito García Lázara Rojas Rivero Irais Atencio Millán raúl CordovíPrado Department of Parasitology Tropical Medicine Institute"Pedro Kourí"HavanaCuba Provincial Centre of Hygiene Epidemiology and Microbiology of Sancti SpíritusCuba

Objective:To determine the prevalence of sub-assemblages of Giardia duodenalis(***)causing infection in preschool children in a central region of ***:A cross-sectional study was conducted on 417 children from Sancti Spiritus from January to June 2013.A PCR amplification of the glutamate dehydrogenase(gdh)gene was performed for all positive samples in direct microscopic examination to enable sub-assemblages ***:The prevalence of *** in preschool children was 10.8%.DNA from 39 of 45(86.7%)samples was successfully amplified by PCR-restriction fragment length polymorphism analysis of the gdh *** fragment length polymorphism analysis classified the 39 gdh amplicons in sub-assemblages BIII(11,28.2%),AII(8,20.5%)and BIV(4,10.3%).Mixed infections accounted for 41%,with the pattern AII/BIII(12,30.7%)being the *** pain was statistically associated with infection with sub-assemblage ***:Sub-assemblage BIII was the most commonly identified in the population of children studied,and significantly associated with abdominal pain in the symptomatic *** defining tools to discriminate sub-assemblage and genotype levels to correlate with clinical data are needed in further *** studies in endemic settings are required to elucidate the role that assemblage types play in *** infections in vulnerable populations,such as children.

关键词： Giardia duodenalis Prevalence Children Sub-assemblages PCR-restriction fragment length polymorphism Cuba