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Journal of Rare Earths 2023年第8期41卷 1217-1224,I0004页

作者： J.S.Uribe-chavira G.Herrera-Pérez c.R.Santillán-rodríguez R.J.Sáenz-Hernández J.A.Matutes-Aquino M.c.Grijalva-castillo Materials Physics Department Centro de Investigación en Materiales AvanzadosS.C.Miguel de Cervantes 120Chihuahua31136ChihMexico cONAcYT–centro de Investigación en Materiales Avanzados S.C.Miguel de Cervantes 120Chihuahua31136ChihMexico

Fe_(81)Al_(19) polycrystalline alloys doped with Tb(0-0.25 at%) were obtained by arc *** introduction of Tb favors the formation of columnar grains in the micro structure of the alloys,which develops a texture in the [100]crystal *** examination shows that the alloys are composed in great proportion by the disordered body-centered cubic(bcc),A2 phase and by a small proportion of the ordered bcc,B2 *** a consequence of doping with Tb,the lattice parameter increases,so the calculated apparent crystallite size increases,indicating a decrease in dislocation density and therefore in *** change in the magnetostriction with the magnetic field,dλ_(T)/dH,is directly related to strain anisotropy that can favor the iron easy magnetization axis on the [100] *** increase in total magnetostriction is found in the doped alloys with a maximum of 90 × 10^(-6) at 300 K for the alloy containing 0.027 at% *** enhancement is a threefold value of the undoped alloy,which is attributed to the smaller maximum strain value and the preferential orientation formation by the columnar grains.

关键词： FeAl alloy Magnetostriction Rietveld refinement Microstrains Preferred orientation Rare earths

Snapshot Survey of the Presence of Perfluoroalkyl Substances in Products, Articles, and the Environment in Ecuador

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Engineering 2024年第6期37卷 49-61页

作者： Heidelore Fiedler Luis Vega-Bustillos Jenny Arias-Pastrano Lander Vinicio Pérez-Aldás Jose castro-Díaz MTM Research centre School of Science and TechnologyÖrebro UniversityÖrebro 70182Sweden Undersecretariat of Environmental Quality Ministry of EnvironmentWater and Ecological Transition of EcuadorQuito 170525Ecuador Department of Environmental chemistry The Technical University of AmbatoHuachi CampusAmbato 180207Ecuador Alternativavision Ambiental cia.Ltda. Mexico 03100Mexico

The Stockholm convention on Persistent Organic Pollutants(POPs)is a legally binding instrument for 186 Parties(status:April 2023).Accordingly,among other responsibilities,countries are obliged to report the production,import,or export of the POPs listed in Annexes A,B,or c;provide information to registers;maintain inventories;and monitor the presence of POPs in the *** the broader context of international chemicals and waste management,producer responsibilities,harmonized reporting,and compliance with national and international regulations,Ecuador has addressed the newly listed group of perfluorinated alkyl substances(PFAS)in its national implementation plan and sent selected products from its national market for PFAS *** products analyzed came from the initially listed fields of specific exemptions and acceptable purposes,including:fire-fighting foams;photographic aids;greasers/degreasers;various kinds of paper/packaging;textiles;and leather,coatings,cleaners,metal plating,and *** results showed that the three PFAS presently listed in the Stockholm convention could be quantified in only a few samples;additional PFAS,not yet listed in the convention also had low detection *** the number of samples was limited,the samples covered a large spectrum of sample matrices,making it possible to conclude that—once these products become waste and are regulated under the Basel convention—they would not constitute a disposal ***,verification of the presence of PFAS in products on the market is expected to pose an analytical challenge for both,developed and developing countries.

关键词： Emerging or newly listed POPs Stockholm convention Products and articles PFAS analysis Developing countries

Liquid-liquid interfacial tension of equilibrated mixtures of ionic liquids and hydrocarbons

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Science china chemistry 2012年第8期55卷 1519-1524页

作者： rodríguez Héctor ARcE Alberto SOTO Ana Department of chemical Engineering University of Santiago de Compostela E-15782 Santiago de Compostela Spain

Ionic liquids are possible alternative solvents for the separation of aromatic and aliphatic hydrocarbons by liquid-liquid extrac- tion. Interfacial tension is an important property to consider in the design of liquid-liquid extraction processes. In this work, the liquid-liquid interfacial tension and the mutual solubility at 25 ℃ have been measured for a series of biphasic, equilibrated mixtures of an ionic liquid and a hydrocarbon. In particular, the ionic liquids 1-alkyl-3-methylimidazolium bis（trifluorome- thanesulfonyl）imide （with the alkyl substituent being ethyl, hexyl or decyl）, 1-ethyl-3-methylimidazolium ethylsulfate, and 1-ethyl-3-methylimidazolium methanesulfonate have been selected, as well as the hydrocarbons benzene, hexane, ethylben- zene, and octane. The selected sets of ionic liquids and hydrocarbons allow the analysis of the influence of a series of effects on the interfacial tension. For example, the interfacial tension decreases with an increase in the length of the alkyl substituent chain of the cation or with an increase of the degree of charge delocalisation in the anion of the ionic liquid. Also, the interfa- cial tension with the aromatic hydrocarbons is markedly lower than that with the aliphatic hydrocarbons. A smaller effect is caused by variation of the size of the hydrocarbon. Some of the observed trends can be explained from the mutual solubility of the hydrocarbon and the ionic liquid.

关键词： ionic liquid aromatic hydrocarbon aliphatic hydrocarbon interfacial tension liquid-liquid equilibrium

Factors associated with early virological response to peginterferon-α-2a/ribavirin in chronic hepatitis c

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World Journal of Gastroenterology 2013年第12期19卷 1943-1952页

作者： Javier García-Samaniego Miriam Romero Rafael Granados Remedios Alemán Miguel Jorge Juan Dolores Suárez ramón Pérez Gregorio castellano carlos González-Portela Liver Unit Hospital Carlos Ⅲ Centro de Investigación Biómedica en Red de Enfermedades Hepáticas y Digestivas Department of Gastroenterology Hospital Universitario de Gran Canaria Gastroenterology Service Hospital Universitario de Canarias Department of Gastroenterology Hospital Universitario Insular de Gran Canaria Internal Medicine Service Hospital Arquitecto Marcide Gastroenterology Service Hospital Central de Asturias Gastroenterology Service Hospital 12 de Octubre Gastroenterology Service Hospital Policlínico de Vigo

AIM: To evaluate the impact of sociodemographic/clinical factors on early virological response (EVR) to pegin-terferon/ribavirin for chronic hepatitis c (cHc) in clinical practice. METHODS: We conducted a multicenter, cross-sectional, observational study in Hepatology Units of 91 Spanish hospitals. cHc patients treated with peginterferon α-2a plus ribavirin were included. EVR was defined as undetectable hepatitis c virus (HcV)-ribonucleic acid (RNA) or ≥ 2 log HcV-RNA decrease after 12 wk of treatment. A bivariate analysis of sociodemographic and clinical variables associated with EVR was carried out. Independent factors associated with an EVR were analyzed using a multiple regression analysis that included the following baseline demographic and clinical variables: age (≤ 40 years vs > 40 years), gender, race, educational level, marital status and family status, weight, alcohol and tobacco consumption, source of HcV infection, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, and gamma glutamyl transpeptidase (GGT) (≤ 85 IU/mL vs > 85 IU/mL), serum ferritin, serum HcV-RNA concentration (cirrhotic status and ribavirin dose (800/1000/1200 mg/d).RESULTS: A total of 1014 patients were included in the study. Mean age of the patients was 44.3 ± 9.8 years, 70% were male, and 97% were caucasian. The main sources of HcV infection were intravenous drug abuse (25%) and blood transfusion (23%). Seventyeight percent were infected with HcV genotype 1/4 (68% had genotype 1) and 22% with genotypes 2/3. The HcV-RNA level was > 400 000 IU/mL in 74% of patients. The mean ALT and AST levels were 88.4 ± 69.7 IU/mL and 73.9 ± 64.4 IU/mL, respectively, and mean GGT level was 82 ± 91.6 IU/mL. The mean ferritin level was 266 ± 284.8 μg/L. Only 6.2% of patients presented with cirrhosis. All patients received 180 mg of peginterferon α-2a. The most frequently used ribavirin doses were 1000 mg/d (41%) and 1200 mg/d (41%).

关键词： Antiviral therapy Baseline factors Early virological response Peginterferon α-2a Ribavirin

Light sheet microscope scanning of biointegrated microlasers for localized refractive index sensing

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Photonics Research 2024年第8期12卷 1673-1680页

作者： ROSS c.cOWIE MARcEL ScHUBERT SUPA School of Physics and AstronomyUniversity of St AndrewsSt AndrewsUK Humboldt centre for Nano and Biophotonics Department of ChemistryUniversity of CologneCologneGermany

Whispering gallery mode(WGM)microlasers are highly sensitive to localized refractive index changes allowing to link their emission spectrum to various chemical,mechanical,or physical *** recently found applications in biological studies within single cells,in three-dimensional samples such as multicellular spheroids,or in ***,detailed studies of biological samples also need to account for the structural heterogeneity of tissues and live animals,therefore requiring a combination of high-resolution microscopy and laser ***,we design and construct a light sheet fluorescence microscope with a coupled spectrometer for use in microlaser studies for combined high-resolution,high-speed imaging and WGM spectral *** light sheet illumination profile and the decoupled geometry of excitation and emission hereby directly affect the lasing and sensing properties,mainly through geometric constraints and by light coupling *** demonstrate the basic working principle of microlaser spectroscopy under light sheet excitation and measure the absolute refractive index within agarose and in zebrafish tail muscle *** further analyze the light coupling conditions that lead to the occurrence of two separate oscillation *** so-called cross modes can be scanned around the entire microlaser surface,which allows to estimate a surface-averaged refractive index profile of the microlaser environment.

关键词： refractive index excitation

Improvement of transfection with reprogramming factors in urine-derived cells

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BIOcELL 2020年第3期44卷 401-409页

作者： OLIVIA A.ROBLES-rodrÍguez MARÍA J.LOERA-ARIAS JOSÉJ.PÉrez-TRUJILLO ARNULFO VILLANUEVA-OLIVO ernesto PIcÓN-GALINDO LAURA VILLARREAL-MARTÍNEZ ADOLFO SOTO-DOMÍNguez HUMBERTO rodrÍguezROcHA ARAcELY GARcÍA-GARcÍA ODILA SAUcEDO-cÁRDENAS ROBERTO MONTES DE OcA-LUNA Facultad de Medicina Departamento de HistologíaUniversidad Autónoma de Nuevo LeónMonterreyC.P.64460México Hospital Universitario“Dr.JoséEleuterio González González” Servicio de HematologíaUniversidad Autónoma de Nuevo LeónMonterreyC.P.64460México centro de Investigación Biomédica del Noreste Departamento de Genética MolecularInstituto Mexicano del Seguro SocialMonterreyC.P.64720México

Human-induced pluripotent stem cells(iPScs)are an accessible source of adult-derived,patient-specific pluripotent stem cells for use in basic research,drug discovery,disease modeling,and stem cell *** the accessibility of methods to obtain iPScs regardless of the cell source can enhance their clinical ***,our purpose is to report a simple protocol to obtain iPS-like cells from urine-derived renal epithelial cells(REcs)using different extracellular matrices and transfection *** this study,we began by culturing urine-derived cells from healthy donors to establish a primary culture of renal epithelial cells,followed by their ***,we generated iPS-like cells by transfecting renal epithelial cells(REcs)with vectors expressing Oct4,Sox2,L-Myc,Lin-28,and Klf4,and we compared the efficacy of different extracellular matrices and transfection *** resultant iPS-like cells showed a human embryonic stem cell-like morphology and expressed the specific pluripotency markers Oct3/4,Nanog,Lin28,and *** concluded that Lipofectamine Stem cell transfection reagent is more effective than FuGENE in obtaining iPS-like cells under the conditions ***,the three matrices are similar in their efficiency of obtaining iPS-like *** report provides an experimental protocol for obtaining and generating iPS-like cells from urine samples for further cell therapy research on different human diseases.

关键词： Reprogramming factors iPScs Renal epithelial cells Extracellular matrix Transfection reagent

Near shore seismic movements induced by seaquakes using the boundary element method

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Earthquake Engineering and Engineering Vibration 2017年第3期16卷 571-585页

作者： Alejandro rodríguez-castellanos Manuel carbajal-Romero Norberto Flores-Guzmán J.Efraín rodríguez-Sánchez Andriy Kryvko instituto mexicano del petróleo eje central lázaro cárdenas 152Gustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalupalmEdif.5Av.Instituto Politécnico Nacional S/NCol.LindavistaGustavo A.MaderoDistrito FederalMéxico escuela superior de ingeniería mecánicay eléctrica instituto politécnico nacionalunidad profesional azcapotzalcoDistrito FederalMéxico centro de investigación en matemáticas jalisco s/nmineral de valencianaguanajuatoMéxico

This study quantifies seismic amplifications in near-shore arising from seaquakes. Within the Boundary Element Method, boundary elements are used to irradiate waves and force densities obtained for each element. Huygens′ Principle is implemented since the diffracted waves are constructed at the boundary from which they are radiated, which is equivalent to Somigliana′s theorem. Application of boundary conditions leads to a system of integral equations of the Fredholm type of second kind and zero order. Several numerical configurations are analyzed： The first is used to verify the present formulation with ideal sea floor configurations to estimate seismic amplifications. With the formulation verified, simple slope configurations are studied to estimate spectra of seismic motions. It is found that P-waves can produce seismic amplifications from 1.2 to 3.9 times the amplitude of the incident wave. SV-waves can generate seismic amplifications up to 4.5 times the incident wave. Another relevant finding is that the highest amplifications are at the shore compared to the ones at the sea floor.

关键词： seismic amplifications seaquake earthquake elastic waves boundary element method near shore cities

A toast to a zebrafish germ cell induction cocktail

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Science china(Life Sciences) 2024年第6期67卷 1314-1315页

作者： Mary c.Mullins Department of cell and Developmental Biology University of Pennsylvania Perelman School of MedicinePhiladelphia 19104USA

The zebrafish field is ringing in the new year with a publication from Yonghua Sun's laboratory(Wang et al.,2023)of a cocktail of germline factors that can induce all cells of the zebrafish embryo into primordial germ cells(PGcs)at phenomenal *** major advance is not only of great interest to germ cell biologists,but it has important applications to the entire zebrafish field,as shown in Wang et al.(2023).

关键词： fish zebra field

clinical significance of"anti-HBc alone"in human immunodeficiency virus-positive patients

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World Journal of Gastroenterology 2009年第10期15卷 1237-1241页

作者： M~aTeresa Pérez-rodríguez Bernardo Sopea Manuel crespo Alberto Rivera Teresa González del Blanco Antonio Ocampo césar Martínez-Vázquez Infectious Diseases Unit Internal Medicine DepartmentXeral-Cíes University Hospital36204 VigoSpain Faculty of Medicine University of Santiago de Compostela15705 Santiago de CompostelaA CoruaSpain Infectious Diseases Department Vall d' Hebron Hospital08035 BarcelonaSpain Microbiology Department Xeral-Cíes University Hospital36204 VigoSpain

AIM： TO determine the prevalence and clinical relevance of isolated antibodies to hepatitis B core antigen as the only marker of infection （“anti-HBc alone”） among human immunodeficiency virus （HIV） type-1 infected patients. Occult hepatitis B infection frequency was also evaluated. METHODS： Three hundred and forty eight histories from 2388 HIV-positive patients were randomly reviewed. Patients with serological markers of hepatitis B virus （HBV） infection were classified into three groups： past hepatitis, ＂anti-HBc alone＂ and chronic hepatitis. Determination of DNA from HBV, and RNA and genotype from hepatitis c virus （HcV） were performed on ＂anti-HBc alone＂ patients. RESULTS： One hundred and eighty seven （53.7%） HIV-positive patients had markers of HBV infection： 118 past infection （63.1%）, 14 chronic hepatitis （7.5%） and 55 ＂anti-HBc alone＂（29.4%）. Younger age [2.3-fold higher per every 10 years younger; 95% confidence intervals （cl） 1.33-4.00] and antibodies to HcV infection [odds ratio （OR） 2.87; 95% cI 1.10-7.48] were factors independently associated with the ＂anti-HBc alone＂ pattern. No differences in liver disease frequency were detected between both groups. Serum levels of anti-HBs were not associated with HcV infection （nor viral replication or HcV genotype）, or with HIV replication or cD4 level. No ＂anti-HBc alone＂ patient tested positive for HBV DNA. cONcLUSION：＂Anti-HBc alone＂ prevalence in HIM- positive patients was similar to previously reported data and was associated with a younger age and with antibodies to HcV infection. In clinical practice, HBV DNA determination should be performed only in those patients with clinical or analytical signs of liver injury,

关键词： Human immunodeficiency virus "Anti-HBcalone" Occult hepatitis Hepatitis B virus DNA Liverdisease

chebyshev multidomain pseudospectral method to solve cardiac wave equations with rotational anisotropy

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International Journal of Modeling, Simulation, and Scientific computing 2018年第4期9卷 58-82页

作者： Jairo rodrıguez-Padilla Daniel Olmos-Liceaga Departamento de Matematicas Universidad de Sonora.Blvd.Rosales y Luis Encinas S/N Col CentroC.P.83000HermosilloSonoraMexico

The implementation of numerical methods to solve and study equations for cardiac wave propagation in realistic geometries is very costly,in terms of computational *** aim of this work is to show the improvement that can be obtained with chebyshev polynomials-based methods over the classical finite difference schemes to obtain numerical solutions of cardiac *** this end,we present a chebyshev multidomain(cMD)Pseudospectral method to solve a simple two variable cardiac models on threedimensional anisotropic media and we show the usefulness of the method over the traditional finite differences scheme widely used in the literature.

关键词： chebyshev-pseudospectral cardiac models anisotropic media.