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Characterization and Comparison of Microbial Soil Diversity in Two Andean Peatlands in Different States of Conservation-Vega Tocorpuri

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Journal of Geoscience and Environment Protection 2018年第4期6卷 194-210页

作者： Carolina Belfiore Ana Fernandez Ana Paula Santos manuel contreras María Eugenia Farías Laboratorio de Investigaciones Microbiològicas de Lagunas Andinas (LIMLA) Planta Piloto de Procesos Industriales Microbiol&#242gicos (PROIMI-CONICET) Tucuma&#225n Argentina Centro de Ecologiía Aplicada (CEA) Suecia Chile

Cerro Tocorpuri, belongs to the II region of Chile, in San Pedro de Atacama, on the border of Chile-Bolivia. The presence of a more or less constant supply of water conditions the existence of characteristic vegetation systems known as bogs (bofedales, vegas and marshes). These wetlands have a cultural, environmental and economic social importance. As a result of the exploitation of aquatic rights, peatlands began to dry up with the consequent loss of natural resources and damage to ancestral rights, and natural resources. The activities of microorganisms in wetlands play an important role in biogeochemical processes. The interaction between microbial diversity and soil, influences to the ability of the ecosystem to recover from stress (resilience). In the present work, the soil characteristics and the associated microbial biodiversity were studied, comparing samples of active and deteriorated peatland. It was seen that the loss of water causes great changes in the physical-chemical characteristics of the soil, which leads to a modification of the microbiota Proteobacteria decreased by 18% in deteriorated peatlands, which are evident more sensible to extreme conditions while Acidobacteria, Actinobacteria increased in these sample showing a better adaptation to the change of conditions. In view of the fact that high Andean Peatlands are exposed to increasing environmental impact, this preliminary comparative study of pristine and altered soil could guide the research directed to recovery of dead peatlands strategies.

关键词： Peatland Microbial Diversity Altered Soil

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Endotoxin-induced alterations of adipose tissue function:a pathway to bovine metabolic stress

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Journal of Animal Science and Biotechnology 2024年第4期15卷 1391-1407页

作者： Miguel Chirivi G.Andres contreras Department of Large Animal Clinical Sciences Michigan State UniversityEast LansingMIUSA

During the periparturient period, dairy cows exhibit negative energy balance due to limited appetite and increased energy requirements for lactogenesis. The delicate equilibrium between energy availability and expenditure puts cows in a state of metabolic stress characterized by excessive lipolysis in white adipose tissues(AT), increased production of reactive oxygen species, and immune cell dysfunction. Metabolic stress, especially in AT, increases the risk for metabolic and inflammatory diseases. Around parturition, cows are also susceptible to endotoxemia. Bacterial-derived toxins cause endotoxemia by promoting inflammatory processes and immune cell infiltration in different organs and systems while impacting metabolic function by altering lipolysis, mitochondrial activity, and insulin sensitivity. In dairy cows, endotoxins enter the bloodstream after overcoming the defense mechanisms of the epithelial barriers, particularly during common periparturient conditions such as mastitis, metritis, and pneumonia, or after abrupt changes in the gut microbiome. In the bovine AT, endotoxins induce a pro-inflammatory response and stimulate lipolysis in AT, leading to the release of free fatty acids into the bloodstream. When excessive and protracted, endotoxin-induced lipolysis can impair adipocyte's insulin signaling pathways and lipid synthesis. Endotoxin exposure can also induce oxidative stress in AT through the production of reactive oxygen species by inflammatory cells and other cellular components. This review provides insights into endotoxins' impact on AT function, highlighting the gaps in our knowledge of the mechanisms underlying AT dysfunction, its connection with periparturient cows' disease risk, and the need to develop effective interventions to prevent and treat endotoxemia-related inflammatory conditions in dairy cattle.

关键词： Adipose tissue dysfunction Endotoxin Inflammation Insulin resistance

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Inversion of walkaway VSP data in the presence of lateral velocity heterogeneity

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Energy Geoscience 2024年第2期5卷 304-313页

作者： Vladimir Grechka Ilya Tsvankin Pedro contreras CWP Department of GeophysicsColorado School of MinesGoldenCO80401USA PDVSA-INTEVEP Apartado 76343Caracas1070AVenezuela Borehole Seismic LLC USA Department of Physics ULAVenezuela

Multi-azimuth walkaway vertical seismic profiling is an established technique for the estimation of in situ slowness surfaces and inferring anisotropy ***,this technique requires the assumption of lateral homogeneity,which makes the horizontal slowness components at depths of downhole receivers equal to those measured at the *** violations of this assumption,such as lateral heterogeneity or nonzero dip of intermediate interfaces,lead to distortions in reconstructed slowness surfaces and,consequently,to errors in estimated anisotropic *** this work,we relax the assumption of lateral homogeneity and discuss how to correct vertical seismic profile data for weak lateral *** describe a procedure of downward continuation of recorded traveltimes that accounts for the presence of both vertical inhomogeneity and weak lateral heterogeneity,which produces correct slowness surfaces at depths of downhole receivers,noticing that sufficiently dense receiver coverage along a borehole is required to separate influences of vertical and lateral heterogeneity on measured traveltimes and obtain accurate estimates of the slowness *** the slowness surfaces are found and a desired type of anisotropic model to be inverted is selected,the corresponding anisotropic parameters,providing the best fit to the estimated slownesses,can be *** invert the slowness surfaces of P-waves for parameters of the simplest anisotropic model describing dipping fractures(transversely isotropic medium with a tilted symmetry axis).Five parameters of this model,namely,the P-wave velocity V0 in the direction of the symmetry axis,Thomsen's anisotropic coefficients e and d,the tilt n,and the azimuth b of the symmetry axis,can be estimated in a stable manner when maximum source offset is greater than half of receiver depth.

关键词： Walkaway vertical seismic profile Lateral velocity heterogeneity Anisotropic parameter estimation Vertical inhomogeneity

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肉鸡砂囊糜烂及前胃炎的致病因素

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国外畜牧学（猪与禽） 2007年第4期27卷 53-55页

作者：黄新新 manuel contreras Douglas Zavieso

许多地方的兽医经常报告肉鸡和商品蛋鸡发生砂囊糜烂。此类病变在许多乡村地区相当普遍，这是因为这些地方的环境条件非常利于霉菌的生长，同时进口饲料原料通常会受到霉菌毒素的污染。遗憾的是，只有少数的病例可借助实验室手段得到临... 详细信息

许多地方的兽医经常报告肉鸡和商品蛋鸡发生砂囊糜烂。此类病变在许多乡村地区相当普遍，这是因为这些地方的环境条件非常利于霉菌的生长，同时进口饲料原料通常会受到霉菌毒素的污染。遗憾的是，只有少数的病例可借助实验室手段得到临床上的确诊，因而此病不大引起人们的重视，除非生产指标受到了负面的影响。

关键词：致病因素糜烂砂囊肉鸡前胃炎霉菌毒素商品蛋鸡乡村地区

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Corrosion testing of X52 and X80 steels immersed in stimulated emulsions using a real petroleum sample

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Petroleum Research 2024年第2期9卷 304-316页

作者： L.M.Quej-Ake J.L.Alamilla A.contreras Instituto Mexicano del Petróleo Eje Central Lázaro CárdenasNorte 152San Bartolo AtepehuacanGustavo A.MaderoCiudad de MéxicoC.P.07730México

The aim of this study is to evaluate the internal corrosion process on X52 and X80 steels/real petroleum interfaces containing condensed hydrocarbon plus oilfield-produced water,which were subjected to stimulated emulsions using 50/50 vol ratio mixtures at 45℃,different hydrodynamic conditions,1 h,and 24 h.A washing process by using deionized water was proposed to simulate and identify the corrosiveness of the hydrocarbon phase after 24 h of exposure *** characterization by electrochemical impedance spectroscopy and the monitoring of the polarization curves indicated that X80 steel/oilfield-produced water interfaces were more susceptible to corrosion than X52 steel exposed to oilfield-produced *** combined speed rotation of 600 rpm using a magnetic stirrer+600 rpm using a rotating disk electrode decreased the corrosion rate on X52 *** stimulated emulsions made of hydrocarbon+oilfield-produced water and hydrocarbon+deionized water at 24 h increased the corrosion rate on X80 steel(0.34 mm/year and 0.43 mm/year,respectively),promoting the formation of erosion and pitting *** types of corrosion depended mainly on the physicochemical properties of the hydrocarbon,oilfield-produced water,exposure times,and hydrodynamic systems in which the hydrocarbon was studied.

关键词： Corrosion Emulsions X52 steel X80 steel

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Remediation of amide pesticide-polluted soils by combined solarization and ozonation treatment

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Pedosphere 2024年第3期34卷 641-651页

作者： Isabel GARRIDO Carmen MMARTINEZ Pilar FLORES Pilar HELLIN Fulgencio contreras Jose FENOLL Department of Sustainability and Quality Group of Fruit and Vegetable Products Instituto Murciano de Investigacion y Desarrollo Agrario y MedioambientalLa Alberca 30150(Spain)

Agriculture has a close relationship with nature,but it can also be the source of negative and permanent environmental *** use of pesticides in modern agriculture is a common practice,but their side effects on the environment cannot be *** this study,we evaluated a combination of solarization and ozonation techniques for the elimination of six amide pesticides(boscalid,chlorantraniliprole,cyflufenamid,fluopyram,napropamide,and propyzamide)in *** experiments were performed with four different soils to assess the efficiency of this methodology at different soil temperatures and ozone dosages under laboratory conditions,and then a greenhouse pot experiment was conducted under controlled conditions during *** days after the onset of the experiments,higher degradation percentages of amide pesticides were observed in ozonized soils than in other treated soils,particularly when ozone was applied at 10 cm soil *** results show that the utilization of ozonation,along with solarization,represents a valid method for degrading residues of the studied pesticides and suggest that this combined technology may be a promising tool for remediating pesticide-polluted soils.

关键词： intermediate ozone pesticide degradation pesticide residue polyethylene film remediation technique

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Sex differences in Alzheimer's disease:an urgent research venue to follow

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Neural Regeneration Research 2024年第12期19卷 2569-2570页

作者： Raquel Jiménez-Herrera Ana contreras Juan D.Navarro-López Lydia Jiménez-Díaz Neurophysiology&Behavior Lab University of Castilla-La ManchaSchool of Medicine of Ciudad RealCiudad RealSpain

Due to increasing life expectancy,the amount of people with dementia worldwide is expected to experience a substantial rise,with estimates indicating a growth from 55 million in 2019 to a staggering 139 million by the... 详细信息

关键词： Alzheimer predominant estimates

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Three-Dimensional Conformal and Intensity Modulated Dynamic Radiotherapy in Juvenile Nasopharyngeal Angiofibroma

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International Journal of Otolaryngology and Head & Neck Surgery 2023年第4期12卷 269-278页

作者： María Fátima Chilaca Rosas David Rafael Salazar Calderon manuel Tadeo contreras Aguilar Carlos Eduardo Barrios Merino Melissa García Lezama Benjamín Conde Castro Shelley Astrid Martínez Torres Katia Hernández Salgado Rafael Medrano Guzmán Radiotherapy Department Oncology Hospital of National Medical Center s. XII Mexican Social Security Institute Mexico City Mexico Directorate of Research General Hospital of Mexico “Dr. Eduardo Liceaga” Mexico City Mexico Research Department in Imaging “Salud Digna” Mexico City Mexico Directorate Oncology Hospital of National Medical Center s. XII Mexican Social Security Institute Mexico City Mexico

Objective: Juvenile Nasopharyngeal Angiofibroma (JNA) is a benign neoplasm with a high vascularity component, greater craniofacial involvement in adolescent patients, and aggressive local behaviour. In unresectable patients, radiotherapy is a therapeutic option for local control. Our aim in this study was to analyze the clinical benefit and local control provided by two modalities of radiotherapy: the Three-Dimensional Conformal (3DC) technique and volumetric modulated arc therapy (VMAT), applied to pediatric patients with JNA considered unresectable and non-recurrent. Methods: In retrospective study, the information was recorded from pediatric patients with a diagnosis of non-recurrent and unresectable JNA treated with radiotherapy at the Oncology Hospital of the National Medical Center SXXI of Mexico City, from March 2010 to March 2021. Radiotherapy management and its association with clinical outcomes of tumour control, and symptoms were assessed. In addition, an evaluation of acute and chronic toxicity was performed. Results: It was found that the median age was 14 years. 9 patients (37.5%) underwent 3DC and 15 (62.5%) VMAT. In terms of local control, and progression-free survival, we did not find significant difference between radiotherapy modalities (p ≤ 0.57). Acute toxicity for both modalities presented statistical differences for radio epithelitis (p = 0.03). Only Grade I and II radiation-induced acute toxicity was observed. Regarding chronic toxicity, statistical significance was observed for craniofacial hypoplasia, in relation to its absence in the VMAT group (p = 0.001). Conclusion: The VMAT presents improvements in dosimetry parameters that improve patient toxicity. In both techniques adequate tumour control was observed, however, the rarity of the disease is a limitation to establish the most appropriate therapeutic technique.

关键词： Intensity-Modulated Radiotherapy Nasopharyngeal Angiofibroma Pediatric Radiotherapy Toxicity

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Uremic Bleeding in 2 Patients with Dieulafoy’s Lesion: Case Report and Literature Review

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Open Journal of Gastroenterology 2024年第5期14卷 167-173页

作者： Gustavo Adolfo Hernández Valdez Diana Estefanía Ibarra García Juan Antonio contreras Escamilla Janette Alejandra Gamiño Gutierrez Francisco manuel Tonatiuh Carrillo Beltran Ulises Solis Gomez Jocelyn Nataly Quintero Meléndez Ivan Alejandro Medina Jimenez Marco Antonio González Villar Jorge Rojas Morales Department of Internal Medicine ISSSTE APP General Hospital of Tepic Tepic Nayarit Mexico Hospital Civil de Guadalajara Fray Antonio Alcalde Guadalajara Jalisco M&#233xico

Dieulafoy’s lesions are rare vascular malformations of the gastrointestinal tract. A Dieulafoy’s lesion is an aberrant vessel that does not reduce in caliber when it extends from the submucosa to the mucosa. Damage to this artery can cause severe and intermittent arterial bleeding from small vascular stumps that are difficult to visualize. Furthermore, these catastrophic bleeding episodes frequently result in hemodynamic instability and the need for transfusion of multiple blood products. Recently, uremic syndrome has been identified as a risk factor for gastric mucosal lesions. We present two clinical cases of acute digestive bleeding due to Dielafoy lesion with chronic kidney disease as the main cause, where two different therapies were performed endoscopically. We concluded with the results of our patients that the best therapy was the application of the hemostatic hemoclip on the injury vs the injection with adrenaline on the wound site. Uremia is identified as a risk factor for upper gastrointestinal bleeding in patients with pre-existing Dieulafoy’s lesion, as well as a higher incidence of new bleeding.

关键词： Dieulafoy’s Lesion Gastrointestinal Bleeding Endoscopy Endoscopy Hemostatic Clips Kidney Disease Adrenaline Thermal Coagulation Dieulafoy

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Geological setting, mining and reduction of mercury vapor contamination in the gold-silver district of Vetas-Calofornia （Santander, Colombia）

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Episodes 2005年第4期28卷 252-256页

作者： Erwin Wolff Carreno Juan manuel Pinzon Angel Rodolfo contreras Moreno Christoph Bernardy Corporacion Autonoma Regional Para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia Formely with Corporacidn Autonoma Regional Para la Defensa de la Mescta de Bucaramanga Carrera 23 N°37-63 Bucaramanga Colombia. Formerly with Federal Institute for Geosciences and Natural Resources Stilleweg 2 30655 Hannover Germany

Bucaramanga, with a population of about one million, is the capital of the Department of Santander （Colombia）, and has the Rio Surata as its main source of drinking water. In the upper reaches of the river, small-scale gold mining has been going onfor many centuries （Vetas-California mining district）. Geologically, the Vetas-California mining district is part of the Santander Massif which is composed of pre-Devonian metamorphic rocks and Mesozoic igneous rocks. The mineralisation is restricted to structurally controlled veins and is often associated with hydrothermal alteration. There is also disseminated mineralisation, but presently only the vein-type is mined. The processing residues are discharged into the nearby watercourses, contaminating the waters of the Surata river basin. As part of a joint Colombian-German technical cooperation project, with the purpose of controlling the negative environmental effects of gold mining pollution, an integrated distillation system for the recovery of mercuury. has been designed and tested.

关键词：地质条件矿床哥伦比亚蒸发作用金银

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