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Journal of Forestry Research 2020年第5期31卷 1759-1771页

作者： Luis A.Leon-Banuelos Angel R.Endara-Agramont William Gomez-Demetrio Carlos G.Martınez-Garcıa E.gabino nava-bernal 50000 TolucaMexicoMexico

The identification of forests infested by parasitic plants is important for the design of appropriate control and prevention *** images and geographic information systems are commonly used to analyze the presence of pest and parasitic plants in the *** there is a need for finer *** the last decade,the use of unmanned aerial vehicles has become increasingly common for capturing aerial images(<10 cm per pixel).The objective of the study was to obtain RGB values(Red,Green and Blue)through the colorimetric ranges for use in identification of Yellow Dwarf Mistletoe(YDM)(Arceuthobium globosum)in aerial images taken in a forest of central Mexico via a programmed *** tonalities of YDM were classified according to its phenological stages,***(young stage),yellow(adult stage),and brown(senescence stage),considering two light intensities,sunny and ***-parametric tests were used in statistical *** Spearman test showed significant negative correlation(p<0.001)between phenological stage and colour,indicating that lower RGB values were associated with greater *** differences between groups were analysed using Kruskal–Wallis(p<0.01)and Mann–Whitney tests(p<0.01).The applied algorithm identified the presence and predominant colours of YDM according to its phenological stage.

关键词： Colorimetric analysis RGB Pinus hartweggi Parasitic plants Remote sensing

Effect of human disturbance on the structure and regeneration of forests in the Nevado de Toluca National Park, Mexico

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Journal of Forestry Research 2012年第1期23卷 39-44页

作者： Angel Rolando Endara Agramont Sergio Franco Maass gabino nava bernal Juan Ignacio Valdez Hernández Todd S.Fredericksen Instituto de Ciencias Agropecuarias y Rurales(ICAR) Universidad Autónoma del Estado de MéxicoInstituto Literario N°100Col.Centro.PO.Box 50000.TolucaMéxico Colegio de Posgraduados Carretera México-TexcocoKm.36.5Montecillo.PO.Box 56230TexcocoMéxico School of Natural Sciences and Mathematics Ferrum CollegeP.O.Box 1000Ferrum VA 24088USA

Sample plots were established in the principal forest types in the the Nevado de Toluca National Park, Mexico including those domi- nated by Pinus hartwegii, Abies religiosa, Quercus laurina and Alnus jorullensis. The vertical structure was defined by three strata in the coniferous forests and two strata in the broadleaved forests. Timber harvesting in Abies religiosa and Quercus laurina forests and fires generated by humans in Pinus hartwegii forests impeded the recruitment of saplings. Mature trees were also heavily impacted by logging in Pinus hartwegii forests. On the contrary, Alnusjorullensis forests were increas- ing due to the disturbance of Pinus and Quercus forests, as well aban- doned crop lands within the park. A combination of logging, uncon- trolled fire, and grazing appears to be compromising the recruitment of important tree species in this national park. These factors, together with human settlements, have also increased the proportion of early succes- sional species. Changes in forest structure from human disturbance indicate a need to control these activities if conservation goals are not to be compromised.

关键词： forest structure human disturbance mountain forests

Analysis of Fragmentation Processes in High-Mountain Forests of the Centre of Mexico

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American Journal of Plant Sciences 2013年第3期4卷 697-704页

作者： Angel Rolando Endara-Agramont Rafael Calderón-Contreras gabino nava-bernal Sergio Franco-Maass Instituto de Ciencias Agropecuarias y Rurales Toluca México Universidad Autónoma Metropolitana D. F. México México

High-mountain forests (>3500 masl) are the main supplier of environmental services to Mexico City and its metropolitan area. Taking as a study case the Nevado de Toluca National Park, this article focuses on the considerable reduction on the density of its forest cover, characterised by disturbances in the structure and dynamics of Pinus hartwegii. This specie is located towards the upper limits of the altitudinal gradient (3500 - 4100 masl) constituting the only pine species in the world capable to be established in those extreme environmental conditions. The information was collected through the implementation of 30 Sampling Plots (SP) of 20 × 50 mts (1000 m2) in three forest density categories: dense, semi-dense and fragmented. For each forest category, all trees ≥2.5 cm DBH were measured in 10 SPs. The measurement variables were DBH, total and commercial height, forest health and forest extraction. The results show the abundance of dense, semi-dense and fragmented forest (336, 202 and 150 trees/Ha-1), with extraction percentages of 11%, 20% and 33% respectively. The horizontal structure distribution shows the shape of an inverted J for the three conditions. However, the phytosanitary conditions of the semi-dense forests (83% infested trees) and fragmented (63% infested trees), do not guaranties the survival of the adult trees, implying an intensification of the fragmentation process for the next decade;given the reduction of the regeneration patterns due to the lack of healthy tree breeding.

关键词： High-Mountain Forests Fragmentation Forest Structure Forest Health

A charged star with geometric Karmarkar condition

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Communications in Theoretical Physics 2023年第8期75卷 139-149页

作者： gabino Estevez-Delgado Joaquin Estevez-Delgado Rafael Soto-Espitia Antonio Rendón Romero Jorge Mauricio Paulin-Fuentes Facultad de Químico Farmacobiología de la Universidad Michoacana de San Nicolás de Hidalgo Facultad de Ciencias Físico Matemáticas de la Universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad Universitaria Facultad de Ingeniería Civil de la Universidad Michoacana de San Nicolás de Hidalgo Edificio A Ciudad Universitaria Facultad de Ingeniería Mecánica de la Universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad Universitaria División Académica de Ciencias Básicas de la Universidad Juárez Autónoma de Tabasco

In this paper,we analyse an analytical solution of the Einstein–Maxwell field equations that considers matter with anisotropic pressures in a static and spherically symmetric *** report the manner in which we obtained the solution,which is by means of the Karmarkar *** the model,we assume a state equation that describes the interaction of matter from quarks P=(c^(2)ρ-4B_(g))/3 and we consider the presence of electric charge,which can generate that the radial and tangential pressures are not *** a graphic manner,we analyse the physical properties of the model,taking as the observational data those of mass 1M⊙and radius7.69 km which were reported for the star Her *** charge values are found between 5.57×10^(18)C≤Q≤1.31×10^(20)C and the interval of the Bag constant Bg∈[118.7,122.13]MeV/fm^(3).Also,we show the stability of the configuration by means of the static stability criteria of Harrison–Zeldovich–Novikov((?M)/?ρc>0),as well as in regards to infinitesimal radial adiabatic perturbation,since the adiabatic indexγ>3.3 which guarantees the stability of the solution.

关键词： general relativity exact solutions anisotropic fluid Karmarkar condition

Strain-induced band gap engineering in layered TiS3

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Nano Research 2018年第1期11卷 225-232页

作者： Robert Biele Eduardo Flores Jose Ramon Ares Carlos Sanchez Isabel J. Ferrer gabino Rubio-Bollinger Andres Castellanos-Gomezs Roberto D'Agosta Nano-Bio Spectroscopy Group and European Theoretical Spectroscopy Facility (EFSF) Universidad del Pals Vasco 20018 San Sebastidn Spain Materials of Interest in Renewable Energies Group (MIRE Group) Dpto. de Fisica de Materiales Universidad Aut6noma de Madrid 28049 Madrid Spain Instituto de Ciencia de Materiales "Nicolds Cabrera" Campus de Cantoblanco 28049 Madrid Spain Dpto. de Ffsica de la Materia Condensada Condensed Matter Physics Center (IFIMAC) Universidad Aut6noma de Madrid Campus de Cantoblanco 28049 Madrid Spain Instituto de Ciencia de los Materiales de Madrid (ICMM-CSIC) Cantoblanco 28049 Madrid Spain IKERBASQUE Basque Foundation for Science 48013 Bilbao Spain

By combining ab initio calculations and experiments, we demonstrate how the band gap of the transition metal trichalcogenide TiS3 can be modified by inducing tensile or compressive strain. In addition, using our calculations, we predicted that the material would exhibit a transition from a direct to an indirect band gap upon application of a compressive strain in the direction of easy electrical transport. The ability to control the band gap and its nature could have a significant impact on the use of TiS3 for optical applications. We go on to verify our prediction via optical absorption experiments that demonstrate a band gap increase of up to 9% （from 0.99 to 1.08 eV） upon application of tensile stress along the easy transport direction.

关键词： band gap engineering titanium trisulfide 2-D materials strain

Contributions of agaves to human health and nutrition

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Food Bioscience 2023年第3期53卷 305-324页

作者： Adonicam Santiago-Martínez Aleyda Pérez-Herrera gabino A.Martínez-Gutiérrez María E.Meneses Instituto Politécnico Nacional Centro Interdisciplinario de Investigación para el Desarrollo Integral Regional(CIIDIR)Unidad OaxacaHornos Av.1003NochebuenaSanta Cruz Xoxocotlán71230OaxacaMexico Consejo Nacional de Humanidades Ciencias y Tecnologías(CONAHCYT)Insurgentes Sur Av.158203940México CityMexico Colegio de Postgraduados Campus PueblaBoulevard Forjadores de Puebla no.205Puebla72760PueblaMexico

The Agave genus has played a key role in the food security of communities at the local and regional level for *** use and knowledge of these plants led to the development of the oldest agricultural centres in ***,a review of the literature on the ethnic and cultural particularities of the use of agave species in food and current knowledge on their nutritional contribution to the human diet is presented.56 species of agaves with food uses were registered by 55 ethnic groups in the American *** this total,23 species also have a medicinal *** number of agave species used by these ethnic groups shows an important agromorphological *** collect and cultivate agaves to use their stem and foliar bases,the floral scape,the flowers and flower buds,the leaves,and the sap to prepare different *** many cases these foods help them survive in adverse *** contribution of agaves to human nutrition has been studied from nutraceutical components such as saponins,inulin,fructans,phenolic compounds and antioxidants,dietary fiber,amino acids,and *** the face of global climate change,agaves represent a strategic biological resource for the world,making their use,conservation and study a *** products will continue to show their health *** use of agaves aids diversification of the genus while contributing to the well-being and permanence of a variety of cultures.

关键词： Agave Edible Food Nutraceutical Health

Anti-inflammatory effects of Mangifera indica *** in a model of colitis

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World Journal of Gastroenterology 2010年第39期16卷 4922-4931页

作者： Lucía Márquez Beatriz G Pérez-Nievas Icíar Gárate Borja García-Bueno José LM Madrigal Luis Menchén gabino Garrido Juan C Leza Department of Pharmacology School of MedicineUniversity Complutense and Centro de Investigación en Red de Salud Mental(CIBERSAM) Pharmaceutical Chemistry Center and University of La Habana Health Research Institute Hospital 12 de Octubre(I+12) Gastroenterology Service Hospital General Universitario Gregorio Maraón and CIBEREHD Department of Chemistry and Pharmacy University Católica del Norte

AIM:To investigate the effect of aqueous extract from Mangifera indica L.(MIE)on dextran sulfate sodium (DSS)-induced colitis in ***:MIE(150 mg/kg)was administered in two different protocols:(1)rectally,over 7 d at the same time as DSS administration;and(2)once daily over 14 d (by oral gavage,7 d before starting DSS,and rectally for 7 d during DSS administration).General observations of clinical signs were ***-inflammatory activity of MIE was assessed by myeloperoxidase(MPO)activity. Colonic lipid peroxidation was determined by measuring the levels of thiobarbituric acid reactive substances (TBARS).Reduced glutathione(GSH)levels,expression of inflammatory related mediators[inducible isoforms of nitric oxide synthase(iNOS)and cyclooxygenase (COX)-2,respectively]and cytokines[tumor necrosis factor(TNF)-αand TNF receptors 1 and 2]in colonic tissue were also ***(IL)-6 and TNF-α serum levels were also measured. RESULTS:The results demonstrated that MIE has anti-inflammatory properties by improvement of clinical signs,reduction of ulceration and reduced MPO activity when administered before *** addition,administration of MIE for 14 d resulted in an increase in GSH and reduction of TBARS levels and iNOS,COX-2, TNF-αand TNF R-2 expression in colonic tissue,and a decrease in IL-6 and TNF-αserum levels. CONCLUSION:MIE has anti-inflammatory activity in a DSS-induced rat colitis model and preventive administration(prior to DSS)seems to be a more effective protocol.

关键词： Oxidative stress Ulcerative colitis Inflammation Polyphenols Mangifera indica Antioxidants

Fast and reliable identification of atomically thin layers of TaSe2 crystals

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Nano Research 2013年第3期6卷 191-199页

作者： Andres Castellanos-Gomez Efren navarro-Moratalla Guillermo Mokry Jorge Quereda Elena Pinilla-Cienfuegos Nicolas Agrait Herre S. J. van der Zant Eugenio Coronado Gary A. Steele gabino Rubio-Bollinger Kavli Institute of Nanoscience Delft University of Technology Lorentzweg 1 2628 CJ Delft The Netherlands Instituto Ciencia Molecular (ICMol) Univ. Valencia C/Catedrdtico Jose Beltrdn 2 E-46980 Paterna Spain Departamento de Fisica de la Materia Condensada (C-III). UniversidadAutonoma de Madrid Campus de Cantoblanco 28049 Madrid Spain Instituto Madrileno de Estudios Avanzados en Nanociencia IMDEA-Nanociencia E-28049 Madrid Spain

Deposition of clean and defect-free atomically thin two-dimensional crystalline flakes on surfaces by mechanical exfoliation of layered bulk materials has proven to be a powerful technique, but it requires a fast, reliable and non-destructive way to identify the atomically thin flakes among a crowd of thick flakes. In this work, we provide general guidelines to identify ultrathin flakes of TaSe2 by means of optical microscopy and Raman spectroscopy. Additionally, we determine the optimal substrates to facilitate the optical identification of atomically thin TaSe2 crystals. Experimental realization and isolation of ultrathin layers of TaSe2 enables future studies on the role of the dimensionality in interesting phenomena such as superconductivity and charge density waves.

关键词： atomically thin layer metal dichalcogenide layered superconductor TaSe2 optical microscopy Raman spectroscopy

Regulatory circuits involving bud dormancy factor PpeDAM6

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Horticulture Research 2021年第1期8卷 3488-3505页

作者： Alba Lloret Carles Quesada-Traver Ana Conejero Vicent Arbona Concepcion Gomez-Mena Cesar Petri Jesus A.Sanchez-navarro Elena Zuriaga Carmen Leida Maria Luisa Badenes gabino Rios Instituto Valenciano de Investigaciones Agrarias 46113 MoncadaValenciaSpain Departament de Ciencies Agraries i del Medi Natural Universitat Jaume ICastello de la PlanaSpain Instituto de Biologia Molecular y Celular de Plantas Universitat Politecnica de Valencia-Consejo Superior de Investigaciones Cientificas46022 ValenciaSpain Departamento de Fruticultura Subtropical y Mediterranea IHSM-UMA-CSICAvenida Dr.Wienbergs/n 29750 Algarrobo-CostaMalagaSpain

DORMANCY-ASSOCIATED MADS-BOX(DAM)genes have recently emerged as key potential regulators of the dormancy cycle and climate adaptation in perennial ***,PpeDAM6 has been proposed to act as a major repressor of bud dormancy release and bud break in peach(Prunus persica).PpeDAM6 expression is downregulated concomitantly with the perception of a given genotype-dependent accumulation of winter chilling time,and the coincident enrichment in H3K27me3 chromatin modification at a specific genomic *** have identified three peach BASIC PENTACYSTEINE PROTEINs(PpeBPCs)interacting with two GA-repeat motifs present in this H3K27me3-enriched ***,PpeBPC1 represses PpeDAM6 promoter activity by transient expression *** the other hand,the heterologous overexpression of PpeDAM6 in European plum(Prunus domestica)alters plant vegetative growth,resulting in dwarf plants tending toward shoot meristem *** alterations in vegetative growth of transgenic lines associate with impaired hormone homeostasis due to the modulation of genes involved in jasmonic acid,cytokinin,abscisic acid,and gibberellin pathways,and the downregulation of shoot meristem factors,specifically in transgenic leaf and apical *** expression of many of these genes is also modified in flower buds of peach concomitantly with PpeDAM6 downregulation,which suggests a role of hormone homeostasis mechanisms in PpeDAM6-dependent maintenance of floral bud dormancy and growth repression.

关键词： homeostasis impaired winter

Severe SARS-CoV-2 Infection: Late Impact on the Retinal Ganglion Cell Layer Thickness

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Open Journal of Ophthalmology 2024年第3期14卷 339-349页

作者： Rayssa de Fátima Farias da Costa gabino Carlos Teixeira Brandt Sebastião Cronemberger UNIFACISA Campina Grande Paraba Brazil Federal University of Minas Gerais Belo Horizonte Brazil

Purpose: The involvement of the ocular anterior segment by SARS-CoV-2 has been the subject of many studies, however, the repercussions on the posterior segment, particularly on the different layers of the retina and optic nerve, are still little known. The purpose of this study was to evaluate the impact of severe COVID-19 on the retinal ganglion cell layer (RGCL) thickness. Methods: This observational, prospective and analytical study was performed in the Ophthalmology Department of the FACISA University Center, Campina Grande. Three groups were included: group I (control), 29 healthy individuals who had not severe COVID-19;group II (infirmary), 24 individuals who had COVID-19 and were hospitalized in the infirmary;and group III, 25 individuals who had severe COVID-19 and required Intense Care Unit (ICU). All individuals had ophthalmologic examination and assessment of RGCL thickness using Optical Coherence Tomography (OCT). Statistical tests required p ≤ 0.05 to reject the null hypothesis. Results: The mean of RGCL thickness was significantly reduced in individuals from GIII (77.9 ± 8.9 µm), as compared with GII (83.9 ± 10.9 µm) and GI (82.8 ± 6.5 µm) (p = 0.0027). The mean measurements from the retinal neve fiber layer (RNFL) of the optic nerve head were similar. However, when evaluated sectoral, the mean of RNFL at the temporal sector of the optic disc was significantly lower in group GIII (p Conclusion: The RGCL thickness from patients with severe COVID-19 was significantly reduced. This finding supports that the SARS-CoV-2 has systemic action and affinity for nerve cells, including those from the retina and are related to the severity of the infection.

关键词： COVID-19 Post-Acute COVID-19 Syndrome Retinal Ganglion Cell