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International Journal of Mining Science and Technology 2023年第5期33卷 555-571页

作者： Alberto Fernández JoséA.Sanchidrián Pablo Segarra Santiago Gómez Enming Li Rafael navarro Universidad Politécnica de Madrid–ETSI Minas y Energía Spain Universidad de Salamanca–GIR Charrock Spain

A procedure to recognize individual discontinuities in rock mass from measurement while drilling(MWD)technology is developed,using the binary pattern of structural rock characteristics obtained from in-hole images for *** from two underground operations with different drilling technology and different rock mass characteristics are considered,which generalizes the application of the methodology to different sites and ensures the full operational integration of MWD data *** approaches are followed for site-specific structural model building:a discontinuity index(DI)built from variations in MWD parameters,and a machine learning(ML)classifier as function of the drilling parameters and their *** prediction ability of the models is quantitatively assessed as the rate of recognition of discontinuities observed in borehole *** between the parameters involved in the models for each site,and differences in their weights,highlight the site-dependence of the resulting *** ML approach offers better performance than the classical DI,with recognition rates in the range 89%to 96%.However,the simpler DI still yields fairly accurate results,with recognition rates 70%to 90%.These results validate the adaptive MWD-based methodology as an engineering solution to predict rock structural condition in underground mining operations.

关键词： Drill monitoring technology Rock mass characterization Underground mining Similarity metrics of binary vectors Structural rock factor Machine learning

Association of PIWIL4 genetic variants with germ cell maturation arrest in infertile Spanish men

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Asian Journal of Andrology 2014年第6期16卷 931-933页

作者： Xavi Munoz Mercedes navarro Ana Mata Lluis Bassas Sara Larriba Human MolecuJar Genetics Group Bellvitge Biomedical Research Institute IDIBELL L'Hospitalet de Llobregat Barcelona Spain Laboratory of Seminology and Embryology Andrology Service-Fundacio Puigvert Barcelona Spain.

Dear Editor, The PIWI proteins （originally P-element-induced wimpy testis in Drosophila） are predominantly present in the germ-line in diverse organisms and are involved in the processing of a class of small RNAs known as piRNAs （see Refs. for review）. The human PIWI protein family consists of four members： PIWIL1-4. Of these, PIWIL4 is known to have essential roles in the first phases ofspermatogenesis： its expression is restricted to gonocytes and it is required for transposon silencing. The lack of this gene in mice causes meiotic arrest in spermatogenesis.

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Carbon stock estimation in halophytic wooded savannas of Uruguay:An ecosystem approach

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Forest Ecosystems 2024年第4期11卷 580-589页

作者： Andres Baietto Andres Hirigoyen Carolina Toranza Franco Schinato Maximiliano Gonzalez Rafael navarro Cerrillo Forest Department Faculty of AgronomyUniversity of the RepublicMontevideoPO 12900Uruguay National Research Program of Forest Production National Agriculture Research InstituteTacuaremboPO 97000Uruguay Soil and Water Department Faculty of AgronomyUniversity of the RepublicMontevideoPO 12900Uruguay Department of Forestry Engineering University of CordobaCordobaPO 14014Spain

Savannas constitute a mixture of trees and shrub patches with a more continuous herbaceous *** contribution of this biome to the soil organic carbon(SOC)and above-ground biomass(AGB)carbon(C)stock globally is ***,they are frequently subjected to land use changes,promoting increases in CO_(2) *** Uruguay,subtropical wooded savannas cover around 100,000 ha,of which approximately 28%is circumscribed to sodic soils(i.e.,subtropical halophytic wooded savannas).Nevertheless,there is little background about the contribution of each ecosystem component to the C stock as well as site-specific allometric *** study was conducted in 5 ha of subtropical halophytic wooded savannas of the national protected area Esteros y Algarrobales del Rio *** work aimed to estimate the contribution of the main ecosystem components(e.g.,soil,trees,shrubs,and herbaceous plants)to the C ***-specific allometric equations for the most frequent tree species and shrub genus were fitted based on basal diameter(BD)and total height(H).The fitted equations accounted for between 77%and 98%of the aerial biomass variance of Netuma affinis and Vachellia *** shrubs(Baccharis sp.),the adjusted equation accounted for 86%of total aerial biomass.C stock for the entire system was 116.71±11.07 Mg·ha^(-1),of which 90.7%was allocated in the soil,8.3%in the trees,0.8%in the herbaceous plants,and 0.2%in the *** results highlight the importance of subtropical halophytic wooded savannas as C sinks and their relevance in the mitigation of global warming under a climate change scenario.

关键词： Carbon stock Climate change Biomass modeling Sodic soils

ApoB-100, ApoE and CYP7A1 gene polymorphisms in Mexican patients with cholesterol gallstone disease

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World Journal of Gastroenterology 2010年第37期16卷 4685-4690页

作者： Sánchez-Cuén Jaime aguilar-Medina Maribel Arámbula-Meraz Eliakym Romero-navarro José Granados Julio Sicairos-Medina Laura Ramos-Payán Rosalío División de Gastroenterología Hospital Regional ISSSTE Facultad de Ciencias Químico Biológicas Doctorado en Biotecnología y Maestría en Ciencias Biomédicas Universidad Autónoma de Sinaloa División de Inmunogenética Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán

AIM: To determine the possible association of the ApoB100 (Xba Ⅰ ), ApoE (Hha Ⅰ ) and CYP7A1 (Bsa Ⅰ ) gene polymorphisms, with the development of cholesterol gallstone disease (GD) in a Mexican population. METHODS: The polymorphisms were analyzed by polymerase chain reaction followed by restriction fragment length polymorphism, in two groups matched by ethnicity, age and sex: patients with GD (n = 101) and stone-free control subjects (n = 101). RESULTS: Allelic frequencies in patients and controls were: 34.16% vs 41.58% (P = 0.124) for X+of ApoB-100; 4.46% vs 5.94% (P = 0.501) for E2, 85.64% vs 78.22% (P = 0.052) for E3, 9.90% vs 15.84% (P = 0.075) for E4 of ApoE; and 25.74% vs 27.72% (P = 0.653) for C of CYP7A1. Differences in genotypic frequencies between the studied groups were not significant (P < 0.05). CONCLUSION: These results demonstrated that no association exists between the studied polymorphisms and cholelithiasis in this high prevalent population.

关键词： Apolipoprotein CYP7A1 Gallstones Mexicans Polymorphisms

Liver Injury from Herbal, Dietary, and Weight Loss Supplements: a Review

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Journal of Clinical and Translational Hepatology 2015年第2期3卷 93-98页

作者： Elizabeth X.Zheng Victor J.navarro Einstein Medical Center Philadelphia PA USA

Herbal and dietary supplement usage has increased steadily over the past several years in the United *** the non-bodybuilding herbal and dietary supplements,weight loss supplements were among the most common type of HDS implicated in liver *** drug induced liver injury is rare,its consequences are significant and on the *** purpose of this review is to highlight case reports of weight loss products such as Hydroxycut and OxyElite Pro as one form of HDS that have hepatotoxic potential and to characterize its clinical effects as well as pattern of liver *** also propose future strategies in the identification and study of potentially hepatotoxic compounds in an effort to outline a diagnostic approach for identifying any drug induced liver injury.

关键词： Drug induced liver injury Herbal and dietary supplements Weight loss supplements

Efficient Solution of a Generalized Eigenvalue Problem Arising in a Thermoconvective Instability

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Communications in Computational Physics 2008年第2期3卷 308-329页

作者： M.C.navarro H.Herrero A.M.Mancho A.Wathen Departamento de Matematicas Facultad de Ciencias QuimicasUniversidad de Castilla-La Mancha13071 Ciudad RealSpain Departamento deMatematicas IMAFFConsejo Superior de Investigaciones Cientificas28006MadridSpain Numerical Analysis Group Computing LaboratoryOxford UniversityOxford OX13QDUnited Kingdom.

The aim of this paper is to develop an efficient numerical method to compute the eigenvalues of the stability analysis of a problem describing the motion of a fluid within a cylindrical container heated non-homogeneously from *** axisymmetric stationary motion settles in,at certain values of the external parameters appearing in the set of partial differential equations modeling the *** basic solution is computed by discretizing the equations with a Chebyshev collocation *** linear stability is formulated with a generalized eigenvalue *** numerical approach(generalized Arnoldi method)uses the idea of preconditioning the eigenvalue problem with a modified Cayley transformation before applying the Arnoldi *** works have dealt with transformations requiring regularity to one of the *** this article we extend those results to the case in which that submatrix is *** method allows a fast computation of the critical eigenvalues which determine whether the steady flow is stable or *** algorithm based on this method is compared to the QZ method and is found to be computationally more *** reliability of the computed eigenvalues in terms of stability is confirmed via pseudospectra calculations.

关键词： Rayleigh-Benard convection Chebyshev collocation preconditioners Arnoldi method Hopf bifurcation.

Structures and characteristics of carbohydrates in diets fed to pigs: a review

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Journal of Animal Science and Biotechnology 2019年第3期10卷 601-617页

作者： Diego M.D.L.navarro Jerubella J.Abelilla Hans H.Stein Department of Animal Sciences University of IllinoisUrbana 61801USA Division of Nutritional Sciences University of IllinoisUrbana 61801USA

The current paper reviews the content and variation of fiber fractions in feed ingredients commonly used in swine *** serve as the main source of energy in diets fed to *** may be classified according to their degree of polymerization: monosaccharides,disaccharides,oligosaccharides,and *** carbohydrates include sugars,digestible starch,and glycogen that may be digested by enzymes secreted in the gastrointestinal tract of the ***-digestible carbohydrates,also known as fiber,may be fermented by microbial populations along the gastrointestinal tract to synthesize short-chain fatty acids that may be absorbed and metabolized by the *** non-digestible carbohydrates include two disaccharides,oligosaccharides,resistant starch,and non-starch *** concentration and structure of non-digestible carbohydrates in diets fed to pigs depend on the type of feed ingredients that are included in the mixed ***,arabinoxylans,and mixed linked β-(1,3)(1,4)-D-glucans are the main cell wall polysaccharides in cereal grains,but vary in proportion and structure depending on the grain and tissue within the *** walls of oilseeds,oilseed meals,and pulse crops contain cellulose,pectic polysaccharides,lignin,and *** crops and legumes also contain significant quantities of galacto-oligosaccharides including raffinose,stachyose,and ***,understanding the structure,characteristics and measurable chemical properties of fiber in feed ingredients may result in more accurate diet formulations,resulting in an improvement in the utilization of energy from less expensive high-fiber ingredients and a reduction in reliance on energy from more costly cereal grains.

关键词： Carbohydrates Carbohydrate composition Chemical structure Feed ingredients Fiber Pigs

Risk factors for postoperative bile leakage:a retrospective single-center analysis of 411 hepatectomies

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Hepatobiliary & Pancreatic Diseases International 2016年第1期15卷 81-86页

作者： Fabrizio Panaro Lisa Hacina Hassan Bouyabrine Al-Warith Al-Hashmi Astrid Herrero Francis navarro Department of General and Liver Transplant Surgery Montpellier University HospitalCollege of Medicine

BACKGROUND： The primary focus of the study was to ana- lyze the risk factors for bile leakage after hepatectomy for be- nign or malignant tumors. METHODS： A total of 411 patients who had undergone hepa- tectomy between December 2006 and December 2011 were ret- rospectively analyzed. The severity of bile leakage was graded according to the ISGLS classification. Twenty-eight pre- and postoperative parameters were analyzed. RESULTS： The overall bile leakage incidence was 10.2% （42/411）. The severity of the leakage was classified according to the IS- GLS classification. Bile leakage was detected early in case of abdominal drainage （11.4% vs 1.9%, P=0.034）. It prolonged the time of hospitalization （16 vs 9 days, P=0.001）. In all patients, wedge resection was associated with a higher incidence of bile leakage in contrast to anatomical resections （25.6% vs 4.1%, P〈0.0001） regardless of the underlying liver disease. Furthermore, total vascular exclusion increased risk of bile leakage （P=0.008）. CONCLUSIONS： Bile leakage as a major issue after hepatic resection is related to the postoperative morbidity and the hospitalization time. It is associated with non-anatomical re- section and a total vascular exclusion.

关键词： liver resection bile leakage wedge total vascular exclusion

Active compounds of medicinal plants,mechanism for antioxidant and beneficial effects

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Phyton-International Journal of Experimental Botany 2019年第1期88卷 1-10页

作者： Orozco Montes F A Vázquez-Hernández B Fenton-navarro Glycobiology Laboratory Postgraduate Studies DivisionFaculty of Medicine and Biological Sciences“Dr.Ignacio Chávez”Michoacán University of Saint Nicholas of Hidalgo(UMSNH)MoreliaMichoacánMexico Hospital of Specialties CMN SXXIIMSSMéxico CityMéxico

An increased interest in the antioxidant effects of medicinal plants has developed in recent *** antioxidant compounds present in medicinal plants and elucidating the mechanism by which they prevent oxidation have been the focus of the research *** performed a systematic and exhaustive review aimed at analyzing the available data regarding the beneficial effects of secondary metabolites in *** result of this review is presented as a description of free radicals,as well as cellular and physiological oxidative stress,is *** origin and source of antioxidant compounds,and the cellular and molecular mechanism by which they exert antioxidant effects,have been *** absorption,distribution and,elimination of antioxidants are *** beneficial effects of secondary metabolites of medicinal plants in various high incidence disease conditions were also ***,disease states that benefit from antioxidant compounds includes diabetes,cancer,cardiovascular diseases,and liver,brain and,intestinal diseases.

关键词： Antioxidants Free radicals Secondary metabolites Polyphenols Oxidative stress Medicinal plants

Chebyshev Collocation for Optimal Control in a Thermoconvective Flow

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Communications in Computational Physics 2009年第2期5卷 649-666页

作者： M.C.navarro H.Herrero S.Hoyas Departamento de Matematicas Facultad de Ciencias QuımicasUniversidad de Castilla-La Mancha13071 Ciudad RealSpain Departamento de Informatica Escuela de IngenierıaUniversidad de Valencia46100 BurjassotValenciaSpain

In this paper a Chebyshev collocation method is used for solving numerically an optimal boundary control problem in a thermoconvective fluid *** aim of this study is to demonstrate the capabilities of these numerical techniques for handling this kind of *** the problem is treated in the primitive variable formulation additional boundary conditions for the pressure and the auxiliary pressure fields are required to avoid spurious modes.A dependence of the convergence of the method on the penalizing parameter that appears in the functional cost is *** this parameter approaches zero some singular behaviour in the control function is observed and the order of the method *** singularities are irrelevant in the problem as a regularized control function produces the same results.

关键词： Chebyshev collocation optimal boundary control Boussinesq-Navier-Stokes