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Journal of Zhejiang University-science B(Biomedicine & Biotechnology) 2007年第12期8卷 912-916页

作者： OGUNLEYE R.f. ADEfEMI s.O. Department of Zoology University of Ado-Ekiti Ado Ekiti Ekiti State 234 Nigeria Department of Chemistry University of Ado-Ekiti Ado Ekiti Ekiti State 234 Nigeria

Insecticidal effects of different doses of the dust and methanol extracts of Garcinia kolae on Callosobruchus maculatus and sitophilus zeamais were tested. The dust had no significant effect on the two insects, none of them died even at 3 d after treatment. The methanol extracts, however, had rapid lethal effects on both C. maculatus and s. zeamais. The mortality of C. maculatus by the lowest concentration of methanol extracts ranged from 95%-100% whereas in s. zeamais, the mortality ranged from 87.5%-100% and 70%-100% in concentrations of 1 g extract＋3 ml methanol and 1 g extract＋5 ml methanol, respectively, from 24 to 48 h. The least concentration of 1 g extract＋l 5 ml methanol had no significant lethal effect on sitophilus zeamais.

关键词： Insecticidal effect Garcinia kolae sitophilus zeamais Callosobruchus maculatus

Cold plumes trigger contamination of oceanic mantle wedges with continental crust-derived sediments:Evidence from chromitite zircon grains of eastern Cuban ophiolites

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Geoscience frontiers 2018年第6期9卷 1921-1936页

作者： J.A.Proenza J.M.gonzález-Jiménez A.Garcia-Casco E.Belousova W.L.Griffin C.Talavera Y.Rojas-Agramonte T.Aiglsperger D.Navarro-Ciurana N.Pujol-solà f.Gervilla s.Y.O’Reilly D.E.Jacob Departament de Mineralogia Petrologia i Geologia AplicadaUniversitat de BarcelonaC/Martíi Franquès s/n08028BarcelonaSpain Departamento de Mineralogía y Petrología Universidad de GranadaFacultad de CienciasFuentenueva s/n 18002GranadaSpain Instituto Andaluz de Ciencias de la Tierra(CsIC-UGR) Avda.de las Palmeras 4E-18100ArmillaGranadaSpain ARC Centre of Excellence for Core to Crust fluid systems(CCfs) GEMOC National Key CentreDepartment of Earth and Planetary SciencesMacquarie UniversitySydneyNSW 2109Australia John de Laeter Centre Curtin UniversityPerthWA 6102Australia Geocycles-Earth system Research Center Institut fur GeowissenschaftenJohannes Gutenberg-UniversitatBecherweg 21D-55099 MainzGermany Departamento de Geociencias Universidad de los AndesBogotáColombia

The origin of zircon grains, and other exotic minerals of typical crustal origin, in mantle-hosted ophiolitic chromitites are hotly debated. We report a population of zircon grains with ages ranging from Cretaceous(99 Ma) to Neoarchean(2750 Ma), separated from massive chromitite bodies hosted in the mantle section of the supra-subduction(ssZ)-type Mayari-Baracoa Ophiolitic Belt in eastern Cuba. Most analyzed zircon grains(n = 20, 287 ± 3 Ma to 2750 ± 60 Ma) are older than the early Cretaceous age of the ophiolite body, show negativeε_(Hf)(t)(-26 to-0.6) and occasional inclusions of quartz, K-feldspar,biotite, and apatite that indicate derivation from a granitic continental crust. In contrast, 5 mainly rounded zircon grains(297±5 Ma to 2126±27 Ma) show positive εHf(t)(+0.7 to +13.5) and occasional apatite inclusions, suggesting their possible crystallization from melts derived from juvenile(mantle)sources. Interestingly, younger zircon grains are mainly euhedral to subhedral crystals, whereas older zircon grains are predominantly rounded grains. A comparison of the ages and Hf isotopic compositions of the zircon grains with those of nearby exposed crustal terranes suggest that chromitite zircon grains are similar to those reported from terranes of Mexico and northern south America. Hence, chromitite zircon grains are interpreted as sedimentary-derived xenocrystic grains that were delivered into the mantle wedge beneath the Greater Antilles intra-oceanic volcanic arc by metasomatic fluids/melts during subduction processes. Thus, continental crust recycling by subduction could explain all populations of old xenocrystic zircon in Cretaceous mantle-hosted chromitites from eastern Cuba *** integrate the results of this study with petrological-thermomechanical modeling and existing geodynamic models to propose that ancient zircon xenocrysts, with a wide spectrum of ages and Hf isotopic compositions, can be transferred to the mantle wedge above subducting slabs by

关键词： Zircon U-Pb geochronology Chromitites Cold plumes Ophiolites Cuba

Emerging bisphenol a replacements(colour developers)in indoor dust from spain

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Emerging Contaminants 2019年第1期5卷 168-172页

作者： María jesús Duenas-Mas Ana Ballesteros-Gomez soledad Rubio Department of Analytical Chemistry Institute of Fine Chemistry and NanochemistryMarie Curie Building AnnexCampus of RabanalesUniversity of Cordoba14071CordobaSpain

Bisphenol A(BPA)and replacements,such as bisphenol s(BPs)and f(BPf)and other substitutes(BPsMAE,D-8 and TGsA)have been recently reported in thermal *** this study,BPA,BPs,BPf;BPs-MAE,D-8 and TGsA were analysed in indoor dust collected in spain from different microenvironments(living rooms,bedrooms,cars and offices).Levels were compared with those reported in our previous study(shops and other public microenvironments,where frequent use of thermal paper is expected).We investigated the differences between microenvironments,possible correlations between compounds and estimated the ingestion ***-MAE,D-8 and TGsA were present at levels up to 529,128 and 356 ng g^-1,respectively,in all the *** highest levels were measured in cars.

关键词： Bisphenol A Bisphenol f Bisphenol s BPs-MAE D-8 TGsA Indoor dust

Biodiesel Production from Castor Oil under subcritical Methanol Conditions

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Biodiesel Production from Castor Oil under Subcritical Metha...

Towards a surreal spin Theory: surreal superstrings?

作者： Nuria sánchez José M.Encinar Gloria Martínez Juan f.gonzález Department of Chemical Engineering and Physical Chemistry University of Extremadura Department of Applied Physics University of Extremadura

Biodiesel is a potentially sustainably renewable fuel for diesel engines;transesterification is the most used method to produce it and high quality vegetable oils are the most usual raw material. Non-edible vegetable oils such as castor oil can provide an alternative feedstock. In this work biodiesel was obtained by transesterification of castor oil with subcritical methanol;the reaction was carried out in an hermetic reactor at temperatures higher than methanol boiling point and with a small amount of potassium methoxide as catalyst. The effect of methanol:oil molar ratios were analyzed, observing that high proportion of alcohol is needed to reach high ester content, the best results were reached with 24:1 Me OH:oil molar ratio. Regarding catalyst concentration, 8.7 m M(0.12 wt%) were enough to achieve good results. A temperature of 150 oC and 1 h of reaction, at 10 bar, were the mildest conditions to reach an ester content higher than 90 wt %. The highest ester content, 94.7 wt %, was achieved at 220 oC, 36 bar and 4 h of reaction time. Hence good quality biodiesel from castor oil can be produced in subcritical methanol conditions, using a small amount of basic catalyst.

关键词： Biodiesel methanol subcritical transesterification

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Journal of Applied Mathematics and Physics 2022年第12期10卷 3586-3600页

作者： Juan Antonio Nieto jesús Adrián félix-Algandar facultad de Ciencias fsico-Matemáticas de la Universidad Autónoma de sinaloa Culiacán Sinaloa México

We propose a surreal spin theory. Our basic mathematical tools are the dyadic rational number which is one of the key mathematical notions in surreal number theory. We argue that from the perspective of such surreal numbers, bosons and fermions, and therefore supersymmetry, are mere particular cases of a very much larger dyadic spin structure which include -spin (semionics), -spin and in general -spin, with m odd integer and n a positive natural number. finally, we conjecture that this development could imply the existence of a surreal superstring theory.

关键词： Higher spin Theory surreal Numbers Dyadic Rationals

synthesis and Thermal Behavior of Metallic Cobalt Micro and Nanostructures

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Nano-Micro Letters 2011年第1期3卷 12-19页

作者： Marlene gonzález Montiel P.santiago-Jacinto J.A.I.Díaz Góngora E.Reguera Geonel Rodríguez-Gattorno Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada Instituto de física Circuito de la Investigación Científica Ciudad Universitaria Departamento de física Aplicada CINVESTAV-IPN

In this contribution, a comparative study of metallic cobalt micro and nanoparticles obtained in solution by four different chemical routes is reported. Classic routes such as borohydride reduction in aqueous media and the so-called polyol methodology were used to obtain the cobalt nanostructures to be studied. Using CTAB as surfactant, cobalt hollow nanostructures were obtained. The use of strong reducing agents, like sodium borohydride, favors the formation of quasi-monodispersed nanoparticles of about 2 nm size but accompanied with impurities; for hydrazine(a mild reducer), nanoparticles of larger size are obtained which organize in spherical microagglomerates. Valuable information on the particles thermal stability and on nature of the species anchored at their surface was obtained from thermogravimetric curves. The samples to be studied were characterized from UV-vis, IR, X-ray diffraction, and electron microscopy images(scanning and transmission).

关键词： Metallic Cobalt Cobalt nanoparticles Magnetic nanoparticles Hollow magnetic microparticles

Role of the HLA-DQ locus in the development of chronic gastritis and gastric carcinoma in Mexican patients

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World Journal of Gastroenterology 2006年第48期12卷 7762-7767页

作者： Roberto Herrera-Goepfert jesús K Yamamoto-furusho Luis f Oate-Ocaa Margarita Camorlinga-Ponce Leopoldo Muoz Jorge A Ruiz-Morales Gilberto Vargas-Alarcón Julio Granados Cellular Biology section Department of Pathology Institute Nacional de Cancerologia (INCan) Mexico City Mexico Department of Immunology and Rheumatology Institute Nacional de Ciencias Medicas y Nutricion Salvador Zubiran Mexico City Mexico Department of Gastroenterology Institute Nacional de Ciencias Medicas y Nutricion Salvador Zubiran Mexico City Mexico Department of Gastroenterology (INCan) Mexico City Mexico Medical Research Unit on Infectious and Parasitic Diseases Hospital de Pediatria Centro Medico Nacional Siglo XXI (CMN-SXXI) Institute Mexicano del Seguro Social (IMSS) Mexico City Mexico Department of Immunology and Rheumatology Institute Nacional de Ciencias Medicas y Nutricion Salvador Zubiran Mexico City Mexico Department of Physiology Institute Nacional de Cardiologia Ignacio Chavez Mexico City Mexico

AIM： To determine the HLA-DQ locus in Mexican patients with Chronic gastritis and gastric adenocarcinoma.METHODs： Oligotyping for HLA-DQ locus was performed in 45 Mexican patients with chronic gastritis and 13 Mexican patients with diffuse-type gastric adenocarcinoma, and was then compared with 99 clinically healthy unrelated individuals. H pylori infection and CagA status were assessed in patients by enzyme-linked immunosorbent assay （EUsA） method. REsULTs： We found a significant increased frequency of HLA-DQBI＊0401 allele in Hpylori-positive patients with chronic gastritis when compared with healthy subjects [19 vs 0%, P = 1 × 10^-7, odds ratio （OR） = 4.96; 95% confidence interval （95% CI）, 3.87-6.35]. We also found a significant increased frequency of HLA-DQBI＊0501 in patients with diffuse-type gastric carcinoma in comparison with healthy individuals （P = 1 × 10^4, OR = 13.07; 95% CI, 2.82-85.14）.CONCLUsION： HLA-DQ locus may play a different role in the development of H pylori-related chronic gastritis and difffuse-type gastric adenocarcinoma in the Mexican Mestizo population.

关键词： HLA-DQ HLA-DQ5 HLA-DQBI*0501 Hpy/or/ Chronic gastritis Gastric cancer Diffuse-type adenocarcinoma

Elastic, thermodynamic, electronic, and optical properties of recently discovered superconducting transition metal boride NbRuB:An ab-initio investigation

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Chinese Physics B 2017年第10期26卷 339-347页

作者： f Parvin s H Naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （LDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DfT calculations electronic band structure optical properties superconductivity

A citation iteration method for publications and scientists evaluation

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Data science and Informetrics 2021年第2期1卷 100-109页

作者： Qiang Liu Jorge Gulín-gonzález Yunwei Chen scientometrics&Evaluation Research Center(sERC) Chengdu Library and Information Center of Chinese Academy of SciencesChengduChina Centro de Estudios de Matemática Computacional(CEMC) Universidad de las Ciencias Informáticas(UCI)Carretera a San Antonio de los BanosKm 2^(1/2)TorrensLa LisaLa HabanaCuba Department of Library Information and Archives ManagementSchool of Economics and ManagementUniversity of Chinese Academy of SciencesBeijingChina

In the last decades many methods have been developed for the evaluation of the quality and impact of both the scientific research papers and *** identifying,discovering,and evaluating high-impact papers using scientometric methods,and adopting reasonable evaluation procedures and methods are vital to stimulating scientists’creative *** of methods used for evaluating impact are:h-index and the cited frequency of articles and the number of highly cited *** we propose a new method to assess the scientist impact based on citation *** method was inspired in the Page Rank *** the present study,both the number of citations and the citing publications after each citation were *** to the obtained results,the proposal allows a more accurate measurement of the impact of scientific ***,the application of this method,it can greatly improve the judgment efficiency of high-impact *** have also conducted an empirical study at three levels in the discipline of mathematics,namely the comparisons of two publications,two scientists and eight *** show that indexes proposed in this dissertation designed for the publications’impacts evaluation and scientists’impact evaluation can be used to find the cause behind the number of cited frequencies resulting in the impact *** Q-index for publications’impacts evaluation and f-index for scientists’impacts evaluation proposed in this article can be used more accurately to check and evaluate the impact of ***,these new indexes can be used in the research management of departments at all levels,and can be useful by the states to find leading scientists in several fields.

关键词： scientist Evaluation Citation network Algorithm scientometric Method

Quality of life in the elderly: Psychometric properties of the WHOQOL-OLD module in Mexico

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Health 2013年第12期5卷 110-116页

作者： Ana Luisa gonzález-Celis Juana Gómez-Benito Department of Behavioral sciences Methodology Faculty of Psychology University of Barcelona Barcelona Spain 3Institute for Brain Cognition and Behaviour (IR3C) University of Barcelona Barcelona Spain Division of Research and Graduate studies Faculty of Higher Education Iztacala National Autonomous University of Mexico Mexico City Mexico

The purpose was to examine and compare the psychometric properties of a Mexican spanish version of the WHOQOL-OLD module. The instrument was applied to 285 individuals aged over 60 years (mean = 69.26, sD = 6.52). All participants completed a demographic data sheet, the WHOQOL-OLD, the Beck Depression Inventory (BDI), and the Geriatric Depression scale (GDs);182 of the 285 participants also completed a quality of life questionnaire for diabetic patients (DQOL). Acceptable levels of reliability were found, with Cronbach’s alpha values between 0.70 and 0.90 for overall quality of life and all domains except for autonomy, where the alpha value was low. The exploratory factor analysis carried out to examine the construct validity of the instrument yielded six domains: sensory abilities, autonomy, past/present/future activities, social participation, death and dying, and intimacy (explained variance of 62.95%). The mean overall quality of life score was 94.86 (sD = 13.68, range 50 to 120). The WHOQOL-OLD module showed criterion validity and concurrent validity with respect to the BDI (r = -0.516, p = 0.034), the GDs (r = -0.336, p = 0.002), and the DQOL (n = 182, r = 0.159, p = 0.032). Discriminant validity was also confirmed with respect to self-perceived health (t = 2.701, d.f. = 225, p = 0.007) and education (f(3, 280) = 9.015, p p > 0.05). We conclude that the Mexican spanish version of the WHOQOL-OLD module has adequate psychometric properties.

关键词： Quality of Life Elderly WHOQOL-OLD Psychometric Properties Mexico