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N-Acetylated Gemini Surfactants: Synthesis, Surface-Active Properties, Antifungal Activity, and Ecotoxicity Bioassays

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Advances in Chemical Engineering and Science 2015年第2期5卷 215-224页

作者： Laura M. Machuca Ulises Reno Silvana C. Plem ana María Gagneten Marcelo C. Murguía Laboratory of Applied Chemistry Faculty of Biochemistry and Biological Sciences National University of Litoral Santa Fe Argentina Laboratory of Ecotoxicology Faculty of Humanities and Sciences National University of Litoral Santa Fe Argentina

A series of N-acetylated cationic gemini surfactants (3a-e) having dimeric structures derived from tertiary amines were synthesized. Their antifungal potency and surface properties were determined. It also studied the acute toxicity of the molecule with the best performance and the best water solubility (3e) through Chlorella vulgaris and Daphnia magna bioassays. The results were compared to those obtained for a commercially available reference compound 2-(thiocyanomethylthio) benzothiazole (TCMTB). Parameters such as surface tension (ϒCMC), critical micelle concentration (CMC), surface excess concentration (Γ), and area per molecule (A) were determined. The resulting values indicated that the five gemini surfactants are characterized by good surface-active and self-aggregation properties. All surfactants were tested to evaluate their antifungal activity. Six fungal strains were used to conduct the study. The minimum inhibitory concentration (MIC) value was measured by the fungal growth inhibition. The results of the MICs were compared with two commercially available reference compounds (Fluconazole and TCMTB). The least active molecule was 3e, but 3b and 3d were found to be the most potent compounds with a similar activity for all strains. Candida albicans was the most sensitive one. In contrast, Aspergillus niger was resistant. Ecotoxicity of gemini 3e was assessed: the commercial formulation (TCMTB) was between three and four orders of magnitude more toxic than the gemini one for the biological species tested.

关键词： Gemini Surfactants Surface-Active Properties Antifungal Activity Ecotoxicity Bioassays

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Study on enzymes of industrial interest in digestive viscera: Greater amberjack (Seriola dumerili)

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Journal of Coastal Life Medicine 2017年第6期5卷 233-238页

作者： Vagne Melo Oliveira Thiago PajeúNascimento Caio Rodrigo Dias Assis Ranilson de Souza Bezerra ana Lúcia Figueiredo Porto Laboratory of Bioactive Product Technology–LABTECBIO Department of Morphology and Animal PhysiologyFederal Rural University of PernambucoRecife-PEBrazil Laboratory of Enzymology–LABENZ Department of BiochemistryFederal University of PernambucoRecife-PEBrazil Laboratory of Immunopathology Keizo Asami Federal University of PernambucoRecife-PEBrazil

Objective:To investigate the presence of industrial enzymes (trypsin and chymotrypsin) as well as collagenolytic and fibrinolytic activities of the neglected processing waste of greater amberjackSeriola dumerili(S. dumerili). Methods: The investigations on trypsin, chymotrypsin, collagenolytic and fibrinolytic activities in residues in digestive viscera were performed. The enzymes trypsin and chymotrypsin were physicochemically characterized (including pH- and thermo-stabilities and sensitivity to metal ions and inhibitors). The kinetic parameters were also determined. Collagenolytic and fibrinolytic activities of the crude extract were also investigated. Results:The crude extract ofS. dumerili showed enzymatic activity of (1.4600 ± 0.0011 and (0.7100 ± 0.0079) IU/mg protein for trypsin and chymotrypsin, respectively. The optimal temperature and pH was 60°C and 9 for trypsin and 40°C and 8 for chymotrypsin. The main inhibitory ions were in the following order: fe3+> Cu2+> Zn2+> Cd2+> Hg2+ (trypsin) and Hg2+> fe3+> Zn2+> Cd2+> Mn2+(chymotrypsin). TLCK and benzamidine were the strongest inhibitors for both enzymes. The crude extract also presented collagenolytic activity [(42.44 ± 0.01) IU/mg] and fibrinolytic activity ((26.70 ± 0.05) IU/mL)Conclusions:The crude extract ofS. dumerili showed potential for reuse of its residues and to provide biomolecules of industrial interest like trypsin and to be a source of fibrinolytic enzymes.

关键词： Biomolecules Enzymes Residues Digestive viscera

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Metal Input in Lettuce Grown in Urban Agricultural Soils

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Open Journal of Soil Science 2020年第4期10卷 137-157页

作者： Silke Cram Pilar fernández Horacio Carranza Manuel Hernández Claudia Ponce de León ana M. Noguez Gálvez Instituto de Geografía Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México Facultad de Ciencias Universidad Nacional Autónoma de México Ciudad Universitaria Ciudad de México México

Urban agriculture plays an important role in supplying produces to big cities;however, the quality of water used for irrigation can hinder this activity. Hence, the purpose of this study was to evaluate metal inputs, as well as their transfer and translocation factors, in lettuce (Lactuca sativa L.) crops cultivated in an urban plot. The research was conducted during the dry and rainy seasons. In the former, crops were irrigated with treated wastewater, whereas during the latter, crops were maintained just with rainwater. Composite samples for soils and plants were collected from the same plot during two crop cycles in 2013. Some edaphic variables were measured. Total metal concentration was determined, for both, soils and lettuce plants (leaves and roots). Water soluble and exchangeable soil metal fractions were also analyzed. A multivariate analysis of variance was performed to test for differences between seasons, among the variables analyzed. There were significant differences in edaphic characteristics between seasons. However, there was no difference in total metal content, except for Mn. Concentration of soluble metals was lower than exchangeable metal concentration, for both seasons. There was no correlation in total metal concentration between soils and plants. Transfer factor values were higher for Cd, Mn and Zn for the dry season, while for Cu, fe and Pb were higher during the rainy season, as well as the translocation factors for all metals. Soil characteristics, together with transfer and translocation factors, showed temporal variations, leading to different metal concentrations in the edible lettuce tissues between the two analyzed crop cycles. The incorporation of metals is particular for each site, season and crop management type. Our results indicate that the metal concentration in lettuce tissues places no harm to human health. However, management strategies for urban agriculture must consider specific studies for each site.

关键词： Transfer Factor Translocation Factor Seasonal Variation Wastewater Irrigation

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Solanum lycopersicum: Novelties for Climate Factors and Its Agronomic Management for High Yields

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World Journal of Engineering and Technology 2022年第3期10卷 605-612页

作者： Víctor García-Gaytán Soledad García-Morales ana V. Coria-Téllez Fanny Hernández-Mendoza Janet María León-Morales El Colegio de Michoacán La Piedad México Profesor Investigador Mejoramiento Integral de Plantas a Través de la Genética y Nutrición Vegetal La Piedad México (CONACYT) Centro de Investigación y Asistencia en Tecnología y Diseñ o del Estado de Jalisco Zapopan México Coordinación Académica Región Altiplano Oeste Universidad Autónoma de San Luis Potosí San Luis Potosí México

The intensive production of vegetables such as tomatoes depends on various strategies to achieve high *** of this manuscript is to provide scientific and technological strategies for the intensive production of tomato or other vegetables in mega-production factories. However, with the advancement of knowledge, new improvements in the strategies will be incorporated. We have carried out research related to growth and yield variables in S. Lycopersicum. From this research we have worked on the intensive production of this noble vegetable at an industrial level. The results obtained are improvements in the production system. The improvements include the selection of the appropriate variety, germination and development of seedlings in a certified nursery. Trans-plantation in soil or hydroponics. The conditions of nutrient applications from the irrigation head system. The ventilation system and monitoring of climatic factors both day and night (temperature and relative humidity). Monitoring of macro- and micronutrients in the plant system, including Ca, K, fe, and Zn. Soil fertility analyzes should include: primary and secondary macronutrients (ppm), organic matter (OM), EC, pH, bulk density (BD), and cation exchange capacity (CEC). The nutritional diagnosis to confirm ranges of sufficiency. As a tool in plant nutrition programs, foliar application can include biostimulants and growth regulators. The foregoing can be considered strategies for the integral management of the tomato crop.

关键词： Integrated Management Climate Factors Plant Nutrition Growth Regulators

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Structural and Magnetic Properties of Monophasic Maghemite (γ-fe2O3) Nanocrystalline Powder

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Advances in Nanoparticles 2014年第3期3卷 114-121页

作者： Juan Adrián Ramos Guivar Arturo Isaías Martínez ana Osorio anaya Luis De Los Santos Valladares Lizbet León Félix Angel Bustamante Dominguez Cavendish Laboratory Department of Physics University of Cambridge Cambridge UK Centro de Investigación y Estudios Avanzados del Instituto Politécnico Nacional Cinvestav Unidad Saltillo Ciudad de México México Ciudad de México México Laboratorio de Cerámicos y Nanomateriales Facultad de Ciencias Físicas Universidad Nacional Mayor de San Marcos Lima Perú Laboratorio de Nanotecnología e Innovación Tecnológica Departamento de Química e Ingeniería Química Universidad Nacional Mayor de San Marcos Lima Perú Núcleo de Física Aplicada Instituto de Física Universidade de Brasília Brasília Brasil

Structural and magnetic studies of monophasic maghemite (γ-fe2O3) magnetic nanocrystallites (MNCs) synthesized by the co-precipitation chemical route are reported in this paper. For the synthesis, a starting precursor of magnetite (fe3O4) in basic medium was oxidized at room temperature by adjusting the pH = 3.5 at 80°C in an acidic medium without surfactants. X-ray diffraction (XRD) pattern shows widened peaks indicating nanometric size and Rietveld Refinement confirms only one single-phase assigned to γ-fe2O3 MNCs. High Resolution Transmission Electron Microscopy (HR-TEM) demonstrates the formation of nanoparticles with diameter around D ≈ 6.8 ± 0.1 nm which is in good agreement with Rietveld Refinement (6.4 ± 1 nm). A selected area electron diffraction pattern was carried out to complement the study of the crystalline structure of the γ-fe2O3 MNCs. M(H) measurements taken at different temperatures show almost zero coercivity and remanence indicating superparamagnetic domain and high magnetic saturation.

关键词： Monophasic Nanomaghemite Rietveld Refinement TEM SAED M-H Loops ZFC

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同位素钙铁分析仪在水泥生料配料中的应用

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硅酸盐学报 1980年第2期 171-179页

作者：白友兆建材院水泥研究所同位素钙铁分析仪研制小组

本文介绍了我国水泥生料配料中已成功使用的两种同位素钙铁分析仪。测定CaO含量时,两种仪器都采用了氚-钛源,适当选择脉冲幅度分析器的道宽上限,有效地克服了feKX射线的干扰;测定fe2O3含量时,则分别采用了氚-钛源和氚-锆源,采用补偿式... 详细信息

本文介绍了我国水泥生料配料中已成功使用的两种同位素钙铁分析仪。测定CaO含量时,两种仪器都采用了氚-钛源,适当选择脉冲幅度分析器的道宽上限,有效地克服了feKX射线的干扰;测定fe2O3含量时,则分别采用了氚-钛源和氚-锆源,采用补偿式滤光片,有效地克服了CaKX射线的干扰和Ca原子的基体吸收效应。对典型水泥生料样品的测定结果表明,CaO、fe2O3测定准确度与X射线荧光分析仪基本相同。文中还扼要介绍了两种仪器的大致构造,以及在两个水泥厂的使用情况。

关键词：生料配料 fe 在线钙铁仪生料磨水泥生料射线荧光分析水泥厂 CaO 分析仪同位素源脉冲幅度分析器脉冲高度分析器

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Effective prophylaxis with rFVIIa in young haemophiliacs with inhibitors using a schedule similar to FVIII prophylaxis in non-inhibitor patients

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Health 2013年第7期5卷 1151-1157页

作者： Maria fernanda Lopez-fernandez Carmen Altisent Victor Jimenez-Yuste Faustino Garcia-Candel Carmen Sedano ana Cid Eva Mingot Ramiro Nunez Maria Jose Paloma Inmaculada Soto Manuel Prieto Haematology Complejo Hospitalario Universitario A CorunaA CorunaSpain Haemophilia Unit Hospital Universitario Vall d’HebronBarcelonaSpain Haemophilia Unit Hospital UniversitarioMadridSpain Haemophilia Unit Hospital Universitario Virgen de la ArreixacaMurciaSpain Haematology Complejo Hospitalario Universitario Marques de ValdecillaSantanderSpain Congenital Coagulophaties Unit Hospital Universitario La FeValenciaSpain Haematology Hospital Universitario Carlos HayaMalagaSpain Haematology Hospital Universitario Virgen del RocíoSevillaSpain Haematology Hospital Virgen del CaminoPamplonaSpain Haematology Hospital General de AsturiasOviedoSpain Haematology Hospital General YagüeBurgosSpain

Objective: To assess the role of early prophylaxis with recombinant activated factor VII (rFVIIa) in young haemophiliacs with inhibitors and to determine whether it can reduce bleeding episodes and prevent joint damage. Patients and Methods: Ten severe haemophiliacs, less of three years old, with up to four joint bleeds and inhibitors to FVIII who started early prophylaxis with rFVIIa, were included. A number of haemorrhages/year/patient and haemarthroses/ year/patient were compared before the start of prophylaxis, which include both the time before (initial period) and after inhibitor diagnosis (inhibitor period), with those during prophylaxis (prophylaxis period). Results: The mean time of inhibitor diagnosis was 15.6 months (range: 2.3-34.1). The mean time between inhibitor diagnosis and the start of prophylaxis was 7.1 months (range: 0-23.2), shorter than the time of rFVIIa prophylaxis (mean: 10.3 months;range: 4.1-32.0). Bleeding episodes for the three time periods were 45, 36 and 17, respectively, or 0.29 and 0.51 haemorrhages/year/patient in the two periods prior to prophylaxis compared to 0.17 during prophylaxis. Total haemarthroses for the three-time periods were 7, 5 and 5, respectively. The haemarthroses/year/patient in the pre-prophylaxis period were 0.032 and 0.070, compared to0.049 inthe prophylaxis period. rFVIIa schedules were either 90 μg/kg three times weekly or 90 μg/kg daily. Conclusions: Early prophylaxis with rFVIIa may be efficacious in young haemophiliacs with inhibitors, reducing joint bleeds. After the risky period of inhibitor presence, they are able to continue rFVIII prophylaxis with success assured to prevent arthropathy.

关键词： rFVIIa Haemarthroses Haemophilia Inhibitors Prophylaxis

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The Thermal Stability of (CaTiO₃)1-x (Cr_3/4fe_5/4O₃)_x Ceramic Composites in the Microwave Region

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Materials Sciences and Applications 2016年第4期7卷 202-209页

作者： Francisco Nivaldo Aguiar Freire Manoel Roberval Pimentel Santos Hélio Henrique Barbosa Rocha ana Fabiola Leite Almeida Selma Elaine Mazzetto Antonio Jefferson Mangueira Sales Antonio Sergio Bezerra Sombra Department of Mechanical Engineering Federal University of Ceara Campus do Pici Fortaleza Brazil Western Para federal University (UFOPA) Santarem Brazil Department of Organic and Inorganic Chemistry Federal University of Ceara Campus do Pici Fortaleza Brazil Department of Physics Federal University of Ceara Campus do Pici Fortaleza Brazil

The thermal stability, structural and dielectric properties of the (CaTiO3)1-x(Cr3/4fe5/4O3)x ceramic composites with x = 0, 0.1, 0.5, 0.9 and 1 have been examined in microwave region. The samples were produced via the solid-state reaction. The orthorhombic structural phase of CaTiO3 and trigonal structural phase of Cr3/4fe5/4O3 were confirmed by the X-Ray Powder Diffraction (XRPD). The XRPD patterns for composites reveal the quantities of each original phase present. The infrared spectra of the samples reinforce this structural verification indicating no or minimal occurrence of unwanted reactions. The first sample (x = 0) and last sample (x = 1) in this series exhibit the maximum and the minimum of the relative dielectric permittivity and values range from 140.1 to 8.3 respectively. The measured temperature coefficient of the matrix CaTiO3 was +921 ppm·℃-1 and for the matrix Cr3/4fe5/4O3 was -56 ppm·℃-1. With the study of series of composites, it was possible to make a mathematical prediction for a composition reach the temperature coefficient near zero. The proposed ceramic has potential use as thermostable material in the microwave region and can be applied to resonators, low-noise amplifiers, filters, and so on.

关键词： Ceramics Composites Dielectric Properties

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Photoluminescent Properties of CoMoO_(4)Nanorods Quickly Synthesized and Annealed in a Domestic Microwave Oven

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Advances in Chemical Engineering and Science 2012年第4期2卷 465-473页

作者： ana P.de Moura Larissa H.de Oliveira Paula F.S.Pereira Ieda L.V.Rosa Máximo S.Li Elson Longo Jose A.Varela Chemistry Institute University of Sao Paulo StateAraraquaraBrazil Chemistry Department Federal University of Sao CarlosSao CarlosBrazil Physical Institute University of Sao PauloSao CarlosBrazil

A simple way to prepare α- and β-CoMoO4 nanorods is reported in this paper. CoMoO4xH2O nanorod precursors were obtained using the microwave-assisted hydrothermal (MAH) method. By annealing the as-prepared CoMoO44xH2O precursor at 600℃ for 10 min in a domestic microwave oven, α- and β-CoMoO4 nanorods were prepared. These powders were analyzed by X-ray diffraction (XRD), field emission scanning electron microscopy (fe-SEM), Fourier transform Raman microscopy and ultraviolet visible absorption spectroscopy (UV-vis spectra) as well as photoluminescence (PL) measurements. Based on the results, these materials revealed nanorod morphology. PL spectra obtained at room temperature for α- and β-CoMoO4 particles exhibited maximum components around the blue light emission. The results show that the domestic microwave oven has been successfully employed to obtain α- and β-CoMoO4 nanoparticles.

关键词： Photoluminescence Nanorods Molybdates Microwave-Hydrothermal Method

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Effectiveness and safety of first-generation protease inhibitors in clinical practice:Hepatitis C virus patients with advanced fibrosis

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World Journal of Gastroenterology 2015年第30期21卷 9163-9174页

作者： Javier Salmeron Carmen Vinaixa Ruben Berenguer Juan Manuel Pascasio Juan Jose Sanchez Ruano Miguel angel Serra ana Gila Moises Diago Manuel Romero-Gomez Jose Maria Navarro Milagros Testillano Conrado fernandez Dolores Espinosa Isabel Carmona Jose Antonio Pons Francisco Jorquera Francisco Javier Rodriguez Ramon Perez Jose Luis Montero Rafael Granados Miguel fernandez ana Belen Martin Paloma Munoz de Rueda Rosa Quiles CIBERehd Instituto de Salud Carlos Ⅲ28029 MadridSpain Unit for Clinical Management of Digestive Diseases Complejo Hospitalario Universitario de Granada Instituto de Investigacion Biosanitaria de Granada University Hospital Politecnico La fe Unit for Clinical Management of Digestive Diseases University Hospital Virgen Del Rocio Hospital Toledo University Clinic Hospital of Valencia University General Hospital of Valencia Unit for Clinical Management of Digestive Diseases University Hospital Nuestra Senora de Valme Department of Gastroenterology and Hepatology Agencia Sanitaria Costa del Sol University Hospital Cruces Gastroenterology Unit University Hospital Fundacion Alcorcon University Hospital Virgen Macarena University Hospital Virgen de la Arrixaca Hospital of Leon University General Hospital Reina Sofia Department Gastroenterology and Hepatology University Hospital Central de Asturias University Hospital Reina Sofia University Hospital De Gran Canaria Dr. Negrin Hospital San Pedro de Alcantara

AIM:To evaluates the effectiveness and safety of the first generation,NS3/4A protease inhibitors(PIs) in clinical practice against chronic C virus,especially in patients with advanced fibrosis. METHODS:Prospective study and non-experimental analysis of a multicentre cohort of 38 Spanish hospitals that includes patients with chronic hepatitis C genotype 1,treatment-na?ve(TN) or treatment-experienced(TE),who underwent triple therapy with the first generation NS3/4A protease inhibitors,boceprevir(BOC) and telaprevir(TVR),in combination with pegylated interferon and ribavirin. The patients were treatment in routine practice settings. Data on the study population and on adverse clinical and virologic effects were compiled during the treatment period and during follow ***:One thousand and fifty seven patients were included,405(38%) were treated with BOC and 652(62%) with TVR. Of this total,30%(n = 319) were TN and the remaining were TE:28%(n = 298) relapsers,12%(n = 123) partial responders(PR),25%(n = 260) null-responders(NR) and for 5%(n = 57) with prior response unknown. The rate of sustained virologic response(SVR) by intention-to-treatment(ITT) was greater in those treated with TVR(65%) than in those treated with BOC(52%)(P ferences. By degree of fibrosis,56% of patients were F4 and the highest SVR rates were recorded in the non-F4 patients,both TN and TE. In the analysis by groups,the TN patients treated with TVR by ITT showed a higher SVR(P = 0.005). However,by m ITT there were no significant differences between BOC and TVR. In the multivariate analysis by m ITT,the significant SVR factors were relapsers,IL28 B CC and non-F4; the type of treatment(BOC or TVR) was not significant. The lowest SVR values were presented by the F4-NR patients,treated with BOC(46%) or with TVR(45%). 28% of the patients interrupted the treatment,mainly by non-viral response(51%):this outcome was

关键词： Hepatitis C Boceprevir Telaprevir First-generation protease inhibitors Advanced fibrosis

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