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Covalent and Ionic Bonding between Tannin and Collagen in Leather Making and Shrinking:A MALDI-ToF Study

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Journal of Renewable Materials 2021年第8期9卷 1345-1364页

作者： antonio Pizzi LERMAB-ENSTIB University of LorraineEpinal88000France

Collagen powder hydrolysates were reacted with a solution of commercial mimosa bark tannin *** mixture was prepared at ambient temperature and prepared at 80°C to determine what reactions,if any,did occur between the collagen protein through its amino acids and the polyphenolic condensed *** reaction products obtained were analyzed by matrix assisted laser desorption ionization time-of-flight(MALDI ToF)mass *** between the two materials did appear to occur,with the formation of a relatively small proportion of covalent and ionic linkages at ambient temperature but a considerable proportion of covalent linkages tannin-protein amino acids and the disappearance of ionic *** linkages between the two materials appeared to be by amination of the phenolic–OHs of the tannin by the amino groups of the non-skeletal side chains of arginine,and by esterification by the–COOH groups of glutamic and aspartic acid of the aliphatic alcohol-OH on the C3 site of the flavonoid units heterocycle of the *** proportion of covalent linkages increases markedly and predominate with increasing *** tightening of the tannin-protein covalent network formed may be an additional contributing factor both to leather wear resistance and performance as well to leather shrinking when this is subjected to excessive temperatures.

关键词： Leather collagen vegetal tannins tanning tannin-protein reactions covalent bonds leather cross-linking leather shrinkage MALDI

Effect of rhenium on the microstructure and mechanical behavior of Fe–2.25Cr–1.6W–0.25V-0.1C bainitic steels

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Journal of Materials Science & Technology 2017年第12期33卷 1487-1493页

作者： José antonio Jiménez Manuel Carsí Oscar antonio Ruano Department of Physical Metallurgy Centro Nacional de lnvestigaciones MetalurgicasC.S.I.CAvda.Gregorio del Amo 828040 MadridSpain

A new ferritic creep resistant steel has been developed by eliminating Nb and adding 1.5 mass % Re to a ferritic steel grade T/P23 with the aim of enhancing its mechanical properties at high *** ingots of both steels, new grade and ASTM T/P 23, were hot rolled at 900℃ and then submitted to a thermal treatment consisting of solubilization at 1050℃ and tempering at 700℃. Tempered bainitic microstructures obtained contain second phases reinforcing carbide particles, mainly M_6C and M_（23）C_6 at the boundaries of both, prior austenite grains and bainitic ferrite laths, as well as MC within the grains. Mechanical properties at temperatures ranging from 540 to 600℃ were studied by strain-ratechange tests in compression at strain rates between 10^（-7） and 10^（-4）s^（-1）. These tests showed high stress exponents（n ≥ 20） and activation energies（Q ≈ 400 k J/mol） for both alloys, which were associated with a dislocation movement mechanism with a strong interaction between dislocations and precipitates. On the other hand, a creep exponent of 5 was derived for the stress dependence of minimum creep rate from conventional-type creep tests at 600℃. Although this stress exponent is usually related to a dislocation climb controlled creep mechanism, remarkable microstructural degradation observed with increasing creep time makes difficult to elucidate the true deformation mechanism controlling creep.

关键词： Creep resistant steel T/P23 Thermal treatment Tempered bainite High temperature mechanical properties Creep

A Review of Soy-Tannin Gelling for Resins Applications

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Journal of Renewable Materials 2023年第1期11卷 1-25页

作者： antonio Pizzi LERMAB-ENSTIB University of Lorraine27 rue PhilippeSeguinEpinal88000France

Soy flour(SF),soy protein and soy protein isolates(SPI)have been the focus of increasing research on their application as new materials for a variety of applications,mainly for wood adhesives and other *** too have been the focus of increasing research for similar *** both materials are classed as non-toxic and have achieved interesting results the majority of the numerous and rather inventive approaches have still relied on some sort of hardeners or cross-linkers to bring either of them or even their combination to achieve acceptable *** paper after a presentation of the two materials and their characteristics concentrates on the formation of gels,gelling and even hardening in the case of soy-tannin combined *** chapter than finishes with details of the formation of resins giving suitable wood adhesive of acceptable performance by the covalent coreaction of soy protein and tannin without any other hardener,thus totally bio-sourced,non-toxic and environment friendly as a base of further advances to expect in future by these two materials combination.

关键词： Soy tannin soy-tannin coreaction gelling hardening wood

Estimating Latent Linear Correlations from Fuzzy Frequency Tables

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Communications in Mathematics and Statistics 2024年第3期12卷 435-461页

作者： antonio Calcagnì DPSS University of PadovaVia Venezia 835031 PaduaItaly Member of the GNCS Research Group National Institute of Advanced Mathematics(INdAM)P.le Aldo Moro 500185 RomaItaly

This research concerns the estimation of latent linear or polychoric correlations from fuzzy frequency *** counts are of particular interest to many disciplines including social and behavioral sciences and are especially relevant when observed data are classified using fuzzy categories—as for socioeconomic studies,clinical evaluations,content analysis,inter-rater reliability analysis—orwhen imprecise observations are classified into either precise or imprecise categories—as for the analysis of ratings data or fuzzy-coded *** these cases,the space of count matrices is no longer defined over naturals and,consequently,the polychoric estimator cannot be used to accurately estimate latent linear *** aim of this contribution is ***,we illustrate a computational procedure based on generalized natural numbers for computing fuzzy ***,we reformulate the problem of estimating latent linear correlations from fuzzy counts in the context of expectation–maximization-based maximum likelihood estimation.A simulation study and two applications are used to investigate the characteristics of the proposed ***,the results show that the fuzzy EM-based polychoric estimator is more efficient to deal with imprecise count data as opposed to standard polychoric estimators that may be used in this context.

关键词： Fuzzy frequency Generalized natural numbers Polychoric correlations Fuzzy data analysis

Diagnostic and therapeutic challenges of myeloid sarcoma in the oral cavity

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World Journal of Clinical Cases 2024年第32期12卷 6526-6533页

作者： Melissa Martínez Nieto Luis antonio gonzález Gómez Juan Carlos Gómez Mireles Sarah Monserrat LomelíMartínez Department of Integrated Dentistry Clinics Centro Universitario de Ciencias de la SaludUniversidad de GuadalajaraGuadalajara 44340Mexico Department of Medical and Life Sciences Centro Universitario de la CiénegaUniversidad de GuadalajaraOcotlán 47810Mexico Department of Well-being and Sustainable Development Centro Universitario del NorteUniversidad de GuadalajaraColotlan 46200JaliscoMexico

Myeloid sarcoma(MS)is a rare neoplasm characterized by the proliferation of immature myeloid precursor cells outside the bone *** pathogenesis of MS is complex and not completely ***,it develops in any extramedullary site of the *** this editorial,we discuss the article published by Li et al,which presents a clinical case involving a 32-year-old man who exhibited gingival inflammation in the maxillary *** was initially diagnosed as periodontal ***,clinical evaluation revealed a firm,grayishwhite mass which underscored the need for comprehensive diagnostics to distinguish MS from other oral *** article emphasizes the different clinical presentations of similar case studies in the literature,and highlights the difficulty in diagnosing oral MS due to its rarity and variability in clinical *** treatment of MS depends on the clinical presentation,tumor location,and the patient's response to conventional *** various therapeutic options currently available are analyzed and *** intervention and multidisciplinary management are crucial for improving treatment *** awareness and education about the various clinical presentations of MS lead to earlier diagnosis and timely treatment,thereby enhancing patients'survival and quality of *** research is essential for optimizing therapeutic strategies and addressing the challenges presented by this rare neoplasm.

关键词： Myeloid sarcoma Acute myeloid leukemia Chloroma Granulocytic sarcoma Oropharyngeal neoplasms Gingiva

Catch per unit effort-environmental variables relations in the fishery of white shrimp(Litopenaeus schmitti)from the Gulf of Venezuela

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Agricultural Sciences 2013年第6期4卷 83-90页

作者： Angel antonio Díaz Lugo Orlando José Ferrer Montano Rodolfo Alvarez Luis gonzález Jesús Méndez Manuel Corona Instituto Nacional de Investigaciones Agropecuarias(INIA) Punto FijoVenezuela Departamento de Biología Universidad del ZuliaMaracaiboVenezuela Instituto Socialista de la Pesca y la Acuicultura(INSOPESCA) CaracasVenezuela

During 15 months the white shrimp (Litopenaeus schmitti) fishing zone was characterized ecologically through the obtaining, compilation and analysis of environmental and physicochemical variables, and modeled the distribution of the relative abundance (CPUE) obtained in 21 fishing sites according to the environmental structure defined by the studied variables. A two-way factorial ANOVA with interaction was used to examine the spatial (fishing sites) and temporal (months) dynamics of CPUE, and a principal component analysis (PCA) was used to discern the environmental structure of the study area. To determine if the environmental structure modeled the distribution of white shrimp, the CPUE values were superimposed on maps of the study area showing strata of the most important physicochemical variables identified by PCA. ANOVA confirmed that the CPUE differed significantly among months (F = 15.6;GL = 11;P P = 0.1979);the interaction term was also not significant (F = 0.52;GL = 10;P = 0.8561). The superimposing of the CPUE on temperature and depth strata confirmed that white shrimp showed greater preference for intermediate temperatures and depths. Petróleos de Venezuela, S.A (PDVSA) contemplates the construction of a multiuse pipeline traversing the study area, by which the current environmental structure of the study area is prone to disturbance. Given the precedent effects represented by an aqueduct construction, it seems PDVSA should anticipate measures to minimize its impact on the fisheries of the zone, particularly on the white shrimp fishery.

关键词： Distribution CPUE Litopenaeus schmitti Gulf of Venezuela

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

The Phenols of the Genus <i>Agave</i>(Agavaceae)

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Journal of Biomaterials and Nanobiotechnology 2013年第3期4卷 9-16页

作者： Norma Almaraz-Abarca Eli Amanda Delgado-Alvarado José antonio ávila-Reyes José Natividad Uribe-Soto Laura Silvia gonzález-Valdez Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional Unidad Durango Instituto Politécnico Nacional Durango Dgo México

A review is presented about the studies that have been carried out on the phenolic composition of the species of the genus Agave in order to show which species of the genus has been analyzed, what is the potential of the species of Agave as source of phenolics with important biological activities, and what is the significance of the phenolic profiles as chemotaxonomic markers in the genus. The results of the analysis of a dozen of Agave species reveal an important richness of phenolic compounds, including flavonoids, homoisoflavonoids, and phenolic acids, and a broad diversity of biological activities associated to those compounds, as antioxidant, antibacterial, antifungal, antinematod, and immunomodulatory capabilities. The phenols of Agave also have a major potential as specific chemotaxonomic markers.

关键词： Genus Agave Phenol Profiles Homoisoflavanoids Biological Activity Chemotaxonomic Markers

Scale-Covariant Theory of Gravitation Through Self-Similarity

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Chinese Physics Letters 2012年第5期29卷 33-36页

作者： Jose antonio Belinchon Department of Nuclear Molecular and Atomic PhysicsUniversity Complutense of MadridE-28040Spain

We study the scale-covariant theory of gravitation proposed by Canuto under the self-similar *** considering the matter collineation approach,we deduce the form of the main quantities and obtain some restrictions on the behavior of the gauge function,φ(t).We apply the obtained results to study the Bianchi I,Ⅶo,Ⅸ and Kantowsky Sachs models,and arrive at the conclusion that instead of considering a varying G theory,the solution is only valid for a particular value of the parameter of the equation of state,γ,.This leads us to obtain φ(t) =const,and by taking into account the external condition,Gφ2 =const,we may arrive at the conclusion that G=***,all the obtained solutions are the same as the ones obtained in the framework of general relativity.

关键词： const conclusion considering