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The new Caribbean Nitrogen Index to assess nitrogen dynamics in vegetable production systems in southwestern Puerto Rico

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International Soil and Water Conservation Research 2017年第1期5卷 69-75页

作者： Miguel Oliveras-Berrocales David Sotomayor-Ramirez jorge a.delgado Luis R.Perez-Alegriad USDA-NRCS Arkansas:2603 Federal Building100 E8th AvePine BluffAR 71601USA University of Puerto Rico Mayaguez CampusCollege of Agricultural SciencesDepartment of Agroenvironmental SciencesPO Box 9000MayagüezPR 00680USA USDA-ARS Acting Research LeaderSoil Management and Sugar Beet Research Unit2150 Centre Ave.Building DSuite 100Fort CollinsCO 80526USA University of Puerto Rico Mayaguez CampusCollege of Agricultural SciencesDepartment of Agricultural and Biosystems EngineeringUSA

Nutrient loss from agricultural fields is one of the main factors influencing surface-and ground-water *** fertilizer nitrogen(N)consumption rates in vegetable production systems and horticultural crops in Puerto Rico fluctuate between 112 and 253 kg N/*** nitrogen use efficiency of vegetable crops is low,increasing the potential for nitrogen losses and high residual soil nitrate *** of residual soil N and N losses to the environment can be a difficult *** models such as the USDA-ARS N Index can be used to identify the relative magnitude of varying N-loss pathways and to identify best management *** studies were conducted to quantify residual soil N and crop N removal,and to validate the Nitrogen Index in onion,tropical pumpkin and tomato production systems in the Lajas Valley in southwestern Puerto *** between observed and simulated values were determined to examine the capability of the model for evaluating N *** was good correlation between observed and predicted values for residual soil N(r=0.88)and crop N removal(r=0.99)(p<0.05).In the production systems evaluated,the N volatilization losses ranged from 1 to 4 kg N/ha,the denitrification losses ranged from 18 to 46 kg N/ha,the leaching losses ranged from 155 to 779 kg N/ha,and the residual soil nitrate ranged from 64 to 401 kg N/*** N use efficiency ranged from 15% to 39%.The results obtained showed that the Nitrogen Index tool can be a useful tool for evaluating N transformations in vegetable production systems of Puerto Rico's semi-arid zone.

关键词： Nitrogen index Nitrogen management Residual soil N Crop N removal

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Use of the Nitrogen Index to assess nitrate leaching and water drainage from plastic-mulched horticultural cropping systems of Florida

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International Soil and Water Conservation Research 2016年第4期4卷 237-244页

作者： Edilene C.S.Marchi Lincoln Zotarelli jorge a.delgado Diane L.Rowland Giuliano Marchi Instituto Federal de Educacao Ciencia e Tecnologia de BrasiliaCampus PlanaltinaDFRodovia DF-128-21-Zona Rural de PlanaltinaBrasilia-DF 73380-900Brazil University of Florida-Horticultural Science Department 1241 Fifield HallGainesvilleFL 32611USA USDA-ARS Soil Management and Sugar Beet Research Unit2150 Centre Ave.Building DSuite 100Fort CollinsCO 80526USA Agronomy Department University of FloridaGainesvilleFLUSA Embrapa Cerrados Rod.BR 020km 18CP 08223CEP73310-970 Planaltina DFBrazil

Water quality in Florida is significantly impacted by nitrate(NO_(3)-N)leaching losses from agriculture in a large part of the *** crops are planted across large areas of Florida on coarse sandy soils with low soil water retention and soil organic matter,increasing the potential for NO_(3)-N *** leaching losses from the root zone of vegetable cropping systems can negatively impact *** tools such as the Nitrogen Index(N-Index)are able to quickly assess N use efficiency and losses via NO_(3)-N leaching from agricultural ***,the N-Index provides technical information about N losses pathways tied to agricultural management practices with a great level of confidence;this information has been used by researchers,growers and policymakers as a decision support ***,the current version of the NIndex that has been used for different field crops has not been calibrated to be used in plastic-mulched horticultural cropping *** aim of this work was to calibrate and validate the N-Index for plasticmulched horticultural cropping systems of *** study found that the N-Index tool accurately identified and ranked the risk of N losses in the evaluated horticultural *** N-Index was calibrated for Florida's plastic-mulched horticultural cropping systems using a sensitivity *** adjusted N-Index was validated using compiled data of vegetables grown under plastic mulching systems during three consecutive *** from these studies suggest that the N-Index can be an easy-to-use tool capable of assessing nitrogen management practices for vegetable *** tool can be used to guide nutrient managers in the implementation of best nitrogen management practices that could contribute to reduced NO_(3)-N leaching losses from vegetable systems in Florida,contributing to a smaller environmental footprint and conservation of water quality.

关键词： Florida,nitrogen management Nitrate leaching Water leaching,vegetables,plastic mulch

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A nitrogen index for improving nutrient management within commercial Mexican dairy operations

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International Soil and Water Conservation Research 2016年第1期4卷 1-5页

作者： Uriel Figueroa-Viramontes jorge a.delgado Juan I.Sánchez-Duarte Esmeralda Ochoa-Martínez Gregorio Núñez-Hernández INIFAP Campo Experimental La LagunaBoulevard JoséSantos Valdez#1200 Pte.Col.CentroMatamoros C.P.27440Matamoros CoahuilaMexico USDA ARS2150 Centre AvenueBuilding DFort CollinsCO 80526United States

Some intensive dairy operations in Mexico are contributing to large,negative environmental impacts,especially in regions dominated by high concentrations of *** manure inputs plus additional nitrogen(N)fertilizer has,in some cases,resulted in background nitrate–nitrogen(NO3–N)levels in irrigation water that are so high,it is not safe for human *** reason is that commercial farmers in this region are currently not using any method to rapidly calculate N budgets based on their practices,N inputs and/or crop N *** Nitrogen Index,a quick tool that can be used to conduct an assessment within a few minutes,was developed for Mexico,but needed further testing under commercial field *** conducted studies in 2010 and 2011 and collected soil and crop information from several commercial farming operations to test the *** index accurately assessed(Po0.0001)residual soil nitrate after harvesting corn(Zea mays L.)and oats(Avena sativa L.);and also accurately assessed the N uptake of these crops(Po0.01).The Mexico N Index is a tool that can be used to quickly conduct N balances,show when N is being over-applied,and help reduce over-application,thus reducing N losses to the environment and improving management of dairy forage systems in Mexico.

关键词： Corn Forage systems Manure Mexico Nitrate leaching Nitrogen Index

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Prevalence of Helicobacter pylori infection among patients with esophageal carcinoma

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World Journal of Gastroenterology 2024年第29期30卷 3479-3487页

作者： Miriam López-Gómez Maria Morales Rebeca Fuerte Marta Muñoz Pedro-David delgado-López jorge Francisco Gómez-Cerezo Enrique Casado Department of Medical Oncology Precision Oncology LaboratoryInfanta Sofía University HospitalSan Sebastián de los Reyes 28231MadridSpain Department of Medical Oncology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Internal Medicine Infanta Sofía University HospitalSan Sebastián de los Reyes 28703MadridSpain Department of Pathology Infanta Sofía University HospitalSan Sebastián de los Reyes 28702Spain Department of Neurosurgery Burgos University HospitalBurgos 09006Spain Department of Internal Medicine Infanta Sofía University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain Department of Medical Oncology Infanta Sofia University Hospital and Henares University Hospital Foundation for Biomedical Research and InnovationSan Sebastian de los Reyes 28702MadridSpain

BACKGROUND Helicobacter pylori(***)is a widespread microorganism related to gastric adenocarcinoma(AC).In contrast,it has been reported that an inverse association exists between *** infection and esophageal *** mechanisms underlying this supposedly protective effect remain *** To determine the prevalence of *** infection in esophageal carcinoma patients,we performed a retrospective observational study of esophageal tumors diagnosed in our *** We retrospectively reviewed the prevalence of *** infection in a cohort of patients diagnosed with esophageal *** or previous proton pump inhibitor(PPI)usage was also *** A total of 89 patients with esophageal carcinoma(69 males,77.5%),with a mean age of 66 years(range,26-93 years)were *** was the most frequent pathological variant(n=47,52.8%),followed by squamous cell carcinoma(n=37,41.6%).Fourteen ACs(29.8%)originated in the gastroesophageal junction and 33(70.2%)in the esophageal ***,54 patients(60.7%)presented at stages III and *** *** infection occurred only in 4 patients(4.5%),3 with AC(6.3%of all ACs)and 1 with squamous cell carcinoma(2.7%of all squamous cell tumors).All patients with previous *** infection had stage *** one patient had received prior *** eradication therapy,whereas 86(96.6%)had received previous or concomitant PPI *** In our cohort of patients,and after histologic evaluation of paraffin-embedded primary tumors,we found a very low prevalence of previous *** *** also reviewed the medical history of the patients,concluding that the majority had received or were on PPI *** minimal prevalence of *** infection found in this cohort of patients with esophageal carcinoma suggests a protective role.

关键词： Helicobacter pylori Eradication Esophageal tumor Dysbiosis Proton pump inhibitors Carcinogenesis Microbiota Incidence

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Loggerhead Sea Turtles Hand-Reared in Captivity: Isotopic Insights into Their Inherent Dietary Variation

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Open Journal of Ecology 2024年第5期14卷 435-454页

作者： Brenda Natasha Mejía-Guarnizo Carlos Julio Polo-Silva Guiomar Aminta Jauregui-Romero Antonio delgado-Huertas Centro de Investigaciones en Ciencias Marinas (CICIMAR-IPN) La Paz M&#233xico Marine Biology Program Faculty of Natural Sciences and Engineering Jorge Tadeo Lozano University Santa Marta Colombia Sharky Management and Consulting Oldsmar FL USA Programa de Conservació n de Tortugas y Mam&#237feros Marinos (ProCTMM) Santa Marta Colombia Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR) Armilla Spain

Stable isotope analysis is a widely used method for gathering ecological insights into the diet and feeding habitats of various species. While captive studies often limit lethal sampling and differ from wild conditions, they offer valuable insights into inherent isotopic variations among individuals, which are often assumed to reflect differences between natural populations. In the Sea Turtle Conservation Program, loggerhead turtle hatchlings from different nests were fed. Necropsies were conducted on turtles that died during this period, obtaining bone fragments for analysis. We evaluated the isotopic variation of carbon (δ13C) and nitrogen (δ15N) in bone tissue across six turtle nests (n = 66 samples) and assessed differences in Straight Carapace Length (SCL, n = 71 samples). Using SIBER and nicheROVER in R, we calculated niche width and overlap, while the simmr package determined primary prey assimilation. Despite feeding the hatchlings the same prey, we observed variations in nitrogen isotope assimilation between nests. Nests 4 and 6 had a niche width >1.8‰, indicating consistent consumption frequencies across all prey and >70% niche overlap with other nests. In contrast, nests 1 and 2 showed a narrower niche width (Mugil sp. constituted the primary diet component (>40%) across all groups. This study demonstrates how factors like competition or prey preference can influence the assimilation of diet, even when the source remains constant (inherent variation).

关键词： Stable Isotopes Caretta caretta Head-Starting Nests Straight Carapace Length

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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

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Relativistic charged stellar modeling with a perfect fluid sphere

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Communications in Theoretical Physics 2023年第9期75卷 113-121页

作者： Joaquin Estevez-delgado Joel Arturo Rodríguez Ceballos jorge Mauricio Paulin-Fuentes JoséVega Cabrera Antonio Rendón Romero Facultad de Ciencias Físico Matemáticas de la Universidad Michoacana de San Nicolás de Hidalgo Edificio BCiudad UniversitariaMorelia MichoacánCP 58040Mexico Facultad de Químico Farmacobiología de la Universidad Michoacana de San Nicolás de Hidalgo Tzintzuntzan No.173Col.MatamorosMorelia MichoacánC.P.58240Mexico División Académica de Ciencias Básicas de la Universidad Juárez Autónoma de Tabasco Carretera Cunduacán-Jalpa Km.1Col.La Esmeralda86690CunduacánTabascoMexico Facultad de Ingenieria Mecanica de la Universidad Michoacana de San Nicolás de Hidalgo Edificio W Ciudad UniversitariaCP 58030Morelia MichoacánMexico

In this report we present the generalization of a solution to Einstein's equations with perfect fluid for the case of Einstein–Maxwell with perfect *** effect of the charge is reflected by a parameter,ν,and its interval is determined by the positivity condition from the pressure in the interior of the *** is shown that the solution is stable according to the Zeldovich criteria as well as in relation to the criteria of the adiabatic *** compactness,u=GM/c^(2)R,of this charged model is greater than it is for the chargeless case as a result of the effect of the presence of the *** allows it to represent stars with a high compactness,in particular a graphic analysis is presented for the star SAX J1808.4-3658 with mass M=1.435M_(⊙)and radius R=7.07 *** these data and employing the solution,we obtain that the total maximum charge for the star is Q=2.4085×10^(20)C.

关键词： general relativity exact solutions charged fluid stars models

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Inflammatory effect on the gastrointestinal system associated with COVID-19

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World Journal of Gastroenterology 2021年第26期27卷 4160-4171页

作者： Paulina.delgado-Gonzalez Carlos A Gonzalez-Villarreal jorge A Roacho-Perez Adriana G Quiroz-Reyes Jose Francisco Islas Juan Luis delgado-Gallegos Daniel Arellanos-Soto Kame A Galan-Huerta Elsa N Garza-Treviño Departamento de Bioquimica y Medicina Molecular UANLMonterrey 64610Nuevo LeónMexico Universidad de Monterrey UDEM Vicerrectoria de Ciencias de la SaludMonterrey 66238Nuevo LeonMexico

The severe acute respiratory syndrome-coronavirus-2(SARS-CoV-2)that causes coronavirus disease-2019(COVID-19)has provoked a global pandemic,mainly affecting the respiratory tract;however,a percentage of infected individuals can develop gastrointestinal(GI)*** studies describe the development of GI symptoms and how they affect the progression of *** this review,we summarize the main mechanisms associated with gut damage during infection by SARS-CoV-2 as well as other organs such as the liver and *** only are host factors associated with severe COVID-19 but intestinal microbiota dysbiosis is also observed in patients with severe disease.

关键词： SARS-CoV-2 Gastrointestinal symptoms COVID-19 Gastrointestinal system

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Helicobacter pylori and skin autoimmune diseases

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World Journal of Gastroenterology 2014年第6期20卷 1510-1516页

作者： Eli Magen jorge-Shmuel delgado Allergy and Clinical Immunology Unit Faculty of Health Sciences Ben-Gurion University of The Negev Barzilai Medical Center Faculty of Health Sciences Ben-Gurion University of The Negev Department of Gastroenterology and Hepatology Faculty of Health Sciences Ben-Gurion University of The Negev

Autoimmune skin diseases are characterized by dysregulation of the immune system resulting in a loss of tolerance to skin self-antigen(s). The prolonged interaction between the bacterium and host immune mechanisms makes Helicobacter pylori(H. pylori) a plausible infectious agent for triggering autoimmunity. Epidemiological and experimental data now point to a strong relation of H. pylori infection on the development of many extragastric diseases, including several allergic and autoimmune diseases. H. pylori antigens activate cross-reactive T cells and induce autoantibodies production. Microbial heat shock proteins(HSP) play an important role of in the pathogenesis of autoimmune diseases because of the high level of sequence homology with human HSP. Eradication of H. pylori infection has been shown to be effective in some patients with chronic autoimmune urticaria, psoriasis, alopecia areata and Schoenlein-Henoch purpura. There is conflicting and controversial data regarding the association of H. pylori infection with Beh et's disease, scleroderma and autoimmune bullous diseases. No data are available evaluating the association of H. pylori infection with other skin autoimmune diseases, such as vitiligo, cutaneous lupus erythematosus and dermatomyositis. The epidemiological and experimental evidence for a possible role of H. pylori infection in skin autoimmune diseases are the subject of this review.

关键词： Autoimmune Skin Helicobacter pylori Infection

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Introduction, Establishment, and Invasion of Digitonthophagus gazella (Fabricius, 1787) (Coleoptera: Scarabaeinae) in the Savannas of Venezuela and Colombia

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Natural Resources 2017年第5期8卷 370-381页

作者： jorge Ari Noriega Oona.delgado Joffre Isnar Blanco jorge Gámez José Clavijo Laboratorio de Zoología y Ecología Acuática—LAZOEA Universidad de Los Andes Bogotá Colombia Department of Biogeography and Global Change National Museum of Natural Science (CSIC) Madrid Spain Museo del Instituto de Zoología Agrícola Francisco Fernández Yépez—MIZA Facultad de Agronomía Universidad Central de Venezuela Maracay Venezuela Laboratorio de Entomología Universidad Nacional Experimental del Táchira San Cristóbal Venezuela Fundación Entomológica Andina Mérida Venezuela

The invasion process involves overcoming certain barriers with negative effects on the biodiversity and ecosystem function. This is the case of the African dung beetle Digitonthophagus gazella, which was introduced in the United States and other countries in Central and South America to help in dung removal activity. The distribution of D. gazella has been documented in the Americas, but in Venezuela there is little information. Trying to understand the process of invasion of the Colombian-Venezuelan savannas and measure their potential impact, the information stored in collections and literature was collected. Five new state records were reported for Venezuela, as well as four scenarios of the process of introduction and establishment of this species in the region. Although the amount of records has increased, the number of individuals sampled is still incipient. The possible areas of invasion and the potential negative effects that the presence of this species exerts in these regions are also discussed. In addition, potential areas of invasion and negative effects of this species are discussed. Results emphasize the importance of generating models of the invasive process in order to design programs that monitor the effects incurred by the presence of D. gazella on native species and propose control and mitigation mechanisms.

关键词： Anthropic Introduction Biodiversity Dung Beetles Invasive Species Scarabaeidae

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