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Geometric Study of the Weak Equilibrium in a Weighted Case for a Two-Dimensional Competition Game

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American Journal of Operations Research 2013年第3期3卷 337-341页

作者： López M. Dolores rodrigo javier Sánchez José Manuel Departamento de Matemática Aplicada de la E.T.S.I. Caminos Canales y Puertos Departamento de Matemática Aplicada de la E.T.S.I. Caminos Canales y Puertos. Departamento de Matemática Aplicada E.T.S. de Ingeniería Universidad Pontificia Comillas de Madrid Madrid Spain

In this work, an improvement of the results presented by [1] Abellanas et al. (Weak Equilibrium in a Spatial Model. International Journal of Game Theory, 40(3), 449-459) is discussed. Concretely, this paper investigates an abstract game of competition between two players that want to earn the maximum number of points from a finite set of points in the plane. It is assumed that the distribution of these points is not uniform, so an appropriate weight to each position is assigned. A definition of equilibrium which is weaker than the classical one is included in order to avoid the uniqueness of the equilibrium position typical of the Nash equilibrium in these kinds of games. The existence of this approximated equilibrium in the game is analyzed by means of computational geometry techniques.

关键词： Game Theory Approximated Equilibrium Location Computational Geometry Convex Hull

Surgical site infection following pancreaticoduodenectomy in a referral cancer center in Mexico

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Hepatobiliary & Pancreatic Diseases International 2024年第5期23卷 502-508页

作者： rodrigo Villaseñor-Echavarri javier Melchor-Ruan Mercedes Aranda-Audelo Gabriela Arredondo-Saldaña Patricia Volkow-Fernandez Maria del Carmen Manzano-Robleda Alejandro E Padilla-Rosciano Diana Vilar-Compte Department of Infectious Diseases Instituto Nacional de CancerologíaAv.San Fernando 22Belisario Domínguez Secc 16TlalpanMexico CityMexico School of Medicine Universidad PanamericanaAugusto Rodin No.498Insurgentes MixcoacBenito JuárezMexico CityMexico Department of Digestive Tube and Hepatopancreatobiliary Tumors Instituto Nacional de CancerologíaAv.San Fernando 22Belisario Domínguez Secc 16TlalpanMexico CityMexico Department of Infectious Diseases Hospital Manuel Gea GonzálezCalz.de Tlalpan 4800Belisario Domínguez Secc 16TlalpanMexico CityMexico Gastrointestinal and Endoscopy Department Instituto Nacional de CancerologíaAv.San Fernando 22Belisario Domínguez Secc 16TlalpanMexico CityMexico

Background: Pancreaticoduodenectomy is the standard treatment for resectable periampullary cancer. Surgical site infections(SSI) are common complications with increased morbidity. The study aimed to describe the prevalence, risk factors, microbiology, and outcomes of SSI among patients undergoing pancreaticoduodenectomy. Methods: We conducted a retrospective study in a referral cancer center between January 2015 and June 2021. We analyzed baseline patient characteristics and SSI occurrence. Culture results and susceptibility patterns were described. Multivariate logistic regression was used to determine risk factors, proportional hazards model to evaluate mortality, and Kaplan-Meier analysis to assess long-term survival. Results: A total of 219 patients were enrolled in the study;101(46%) developed SSI. Independent factors for SSI were diabetes mellitus, preoperative albumin level, biliary drainage, biliary prostheses, and clinically relevant postoperative pancreatic fistula. The main pathogens were Enterobacteria and Enterococci. Multidrug-resistance rate in SSI was high but not associated with increased mortality. Infected patients had higher odds of sepsis, longer hospital stay and intensive care unit stay, and readmission rate. Neither 30-day mortality nor long-term survival was significantly different between infected and non-infected patients. Conclusions: SSI prevalence among patients undergoing pancreaticoduodenectomy was high and largely caused by resistant microorganisms. Most risk factors were related to preoperative instrumentation of the biliary tree. SSI was associated with greater risk of unfavorable outcomes;however, survival was unaffected.

关键词： Surgical site infection Pancreaticoduodenectomy Pancreatic cancer Endoscopic biliary drainage Biliary prosthesis

Manipulation of parasite load induces significant changes in the structural-based throat color of male iberian green lizards

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Current Zoology 2018年第3期64卷 293-302页

作者： rodrigo MEGiA-PALMA javier MARTiNEZ Santiago MERINO Dept Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSIC J. Gutierrez Abascal 2 E-28006 Madrid Spain Area Parasitologia Dept Biomedicina y Biotecnologia Area de Parasitologia. Facultad de Farmacia Universidad de Alcala de Henares Alcala de Henares E-28871 Madrid Spain

The honesty of structural-based ornaments is controversial. Sexual selection theory predicts that the honesty of a sexual signal relies on its cost of production or maintenance. Therefore, environmental factors with negative impact on individuals could generate high costs and affect the expres- sion of these sexual signals. In this sense, parasites are a main cost for their hosts. To probe the effect of parasites on the structural-based coloration of a lacertid species Lacerta schreiberi, we have experimentally removed ticks from a group of male Iberian green lizards using an acaricide treatment （i.e., the broad-use insecticide fipronil）. All individuals were radio-tracked and recaptured after 15 days to study changes in coloration in both the ultraviolet （UV）-blue （structural-based） and UV-yellow （structural and pigment-based） ornamentations after manipulation, as well as changes in endoand ectoparasitic load and body condition. Additionally, after the experiment, we measured the skin inflammatory response to a mitogen. The fipronil treatment was effective in reducing ticks and it was associated with a significant reduction of hemoparasite load. Throughout the season, individuals treated with fipronil tended to maintain the brightness of the UV-blue throat coloration while control lizards tended to increase it. However, individuals treated with fipronil that were not infected with hemoparasites significantly reduced the brightness of the UV-blue throat color ation. Individuals with a higher initial tick load exhibited a lower UV saturation increment （UV-blue） and a higher brightness increment （UV-yellow） during the experiment. Overall these results experimentally support the idea that parasites adversely influence the expression of the structural-based coloration of male Iberian green lizards. This adds evidence to the hypothesis that sexual ornaments in lizards function as honest signals.

关键词： animal communication ectoparasites Hamilton & Zuk structural-coloration.

Multiple color patches and parasites in Sceloporus occidentalis:differential relationships by sex and infection

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Current Zoology 2018年第6期64卷 703-711页

作者： rodrigo MEGIA-PALMA Dhanashree PARANJPE Senda REGUERA javier MARTINEZ Robert D COOPER Pauline BLAIMONT Santiago MERINO Barry SINERVO Department of Ecologia Evolutiva Museo Nacional de Ciencias Naturales-CSICJose Gutierrez Abascal 2.Madrid E-28006Spain Departrnent of Ecology and Evolutionary Biology University of CaliforniaSanta Cruz1156High StSanta CruzCA 95064USA Department of Zoologia Facultad de CienciasUniversidad de GranadaGranada E-18071Spain Area Parasitologia Department of Biomedicina y BiotecnologiaArea de ParasitologiaFacultad de FarmaciaUniversidad de Alcala de HenaresAlcala de HenaresMadrid E-28871Spain

Parasites generally have a negative influence on the color expression of their *** selection theory predicts resistant high-quality individuals should show intense coloration,whereas susceptible low-quality individuals would show poor ***,intensely colored males of different species of Oid and New World lizards were more often infected by *** results suggest that high-quality males,with intense coloration,would suffer higher susceptibility to *** hypothesis remains poorly understood and contradicts general theories on sexual *** surveyed a population of Sceloporus occidentalis for parasites and found infections by the parasite genera Lankesterella and *** this population,both males and females express ventral blue and yellow color *** was almost exclusively infecting *** body size of the males significantly predicted the coloration of both blue and yellow *** males showed darker (lower lightness)blue ventral patches and more saturated yellow patches that were also ***,these males were more often infected by Lankesterella than smaller *** intestinal parasite Acroeimeria infected both males and *** infection by intestinal parasites of the genus Acroeimeria was the best predictor for the chroma in the blue patch of the males and for hue in the yellow patch of the *** males infected by Acroeimeria expressed blue patches with significantly lower chroma than the uninfected ***,the hue of the yellow patch was not significantly different between infected and uninfected *** results suggest a different effect of Lankesterella and Acroeimeria on the *** the one hand,the intense coloration of male lizards infected by Lankesterella suggested high-quality male lizards may tolerate *** the other hand,the low chroma of the blue coloration of the infected males suggested that this coloration could honest

关键词： animal communication coloration Hamilton and Zuk parasites sexual selection

IL28B polymorphisms associated with therapy response in Chilean chronic hepatitis C patients

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World Journal of Gastroenterology 2011年第31期17卷 3636-3639页

作者： Mauricio Venegas rodrigo A Villanueva Katherine González javier Brahm Centro de Estudios Avanzados de las Hepatitis Virales Sección de GastroenterologíaDepartamento de MedicinaHospital Clínico Universidad de Chile Centro de Estudios Avanzados de las Hepatitis Virales Laboratorio de Virus HepatitisPrograma de VirologíaInstituto de Ciencias BiomédicasFacultad de MedicinaUniversidad de Chile

AIM:To analyze the association of three IL28B single nucleotide polymorphisms with response to therapy in Chilean patients infected with hepatitis C virus ***:We studied two groups of patients with chronic CV infection genotype 1,under standard combined treatment with pegylated interferon plus *** group consisted of 50 patients with sustained virological response,whereas the second group consisted of 49 null *** order to analyze the IL28B single nucleotide polymorphisms rs12979860,rs12980275 and rs8099917,samples were used for polymerase chain reaction amplification,and the genotyping was performed by restriction fragment ***:The IL28B rs12979860 CC,rs12980275 AA and rs8099917 TT genotypes were much more frequently found in patients with sustained virological response compared to null responders 38%,44% and 50% vs 2%,8.2% and 8.2%,*** differences were highly significant in all three cases(P < ***:The three IL28B polymorphisms studied are strongly associated with sustained virological response to therapy in Chilean patients with chronic CV genotype 1.

关键词： IL28B Hepatitis C virus Chile Pegylated interferon Ribavirin

Duodenal biopsy may be avoided when high transglutaminase antibody titers are present

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World Journal of Gastroenterology 2009年第38期15卷 4775-4780页

作者： Santiago Vivas Jose G Ruiz de Morales Sabino Riestra Laura Arias Dolores Fuentes Noemi Alvarez Sara Calleja Mercedes Hernando Blanca Herrero javier Casqueiro Luis rodrigo Department of Gastroenterology Hospital de León Institute of Biomedicine University of León Immunology Section Hospital de León Department of Gastroenterology Hospital Universitario Central de Asturias Department of Pathology Hospital de León Department of Pediatrics Hospital de León Faculty of Biology and Environmental Sciences University of León

AIM:To evaluate the predictive value of tissue transglutaminase (tTG) antibodies for villous atrophy in adult and pediatric populations to determine if duodenal biopsy can be ***: A total of 324 patients with celiac disease (CD; 97 children and 227 adults) were recruited prospectively at two tertiary centers. Human IgA class anti-tTG antibody measurement and upper gastrointestinal endoscopy were performed at diagnosis. A second biopsy was performed in 40 asymptomatic adults on a gluten-free diet (GFD) and with normal tTG ***: Adults showed less severe histopathology (26% vs 63%, P<0.0001) and lower tTG antibody titers than children. Levels of tTG antibody correlated with Marsh type in both populations (r=0.661, P<0.0001). Multiple logistic regression revealed that only tTG antibody was an independent predictor for Marsh type 3 lesions, but clinical presentation type and age were not. A cut-off point of 30 U tTG antibody yielded the highest area under the receiver operating characteristic curve (0.854). Based on the predictive value of this cut-off point, up to 95% of children and 53% of adults would be correctly diagnosed without biopsy. Despite GFDs and decreased tTG antibody levels, 25% of the adults did not recover from villous atrophy during the second year after ***: Strongly positive tTG antibody titers might be sufficient for CD diagnosis in children. However, duodenal biopsy cannot be avoided in adults because disease presentation and monitoring are different.

关键词： Biopsy Celiac disease Diagnosis Duodenum Transglutaminases

Characterization and Pyrometallurgical Removal of Arsenic from Copper Concentrate Roasting Dust

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Journal of Minerals and Materials Characterization and Engineering 2021年第6期9卷 609-620页

作者： Hector Henao Ignacio Paredes rodrigo Diaz javier Ortiz Metallurgy Engineering Department Technical University Federico Santa María Valparaíso Chile CODELCO Ministro Hales Division Antofagasta Chile

This paper describes the experimental results of removing arsenic from the dust collected in electrostatic precipitators of a fluidized bed roasting furnace (RP dust). The fluidized bed roasting process generates 600 kilotons of copper concentrate per year with 3 - 6 wt% of concentration of arsenic, producing a roasted product with a low content of arsenic below 0.3 wt%. The process generates 27 kilotons of RP dust per year with a concentration of arsenic of the order of 5 wt% and copper concentration of around 20 wt%. Subsequently, the dust collected in the electrostatic precipitators is treated by hydrometallurgical methods allowing the recovery of copper, and the disposition of arsenic as scorodite. This work proposes to use a pyrometallurgy process to the volatilization of arsenic from RP dust. The obtained material can be recirculated in copper smelting furnaces allowing the recovery of valuable metals. The set of experiments carried out in the roasting of the mixture of copper concentrate/RP dust and sulfur/RP dust used different ratios of mixtures, temperatures and roasting times. By different techniques, the characterization of the RP dust determined its size distribution, morphology, and chemical and mineralogical composition. RP dust is a composite material of small particles (<5 μm) in 50 μm agglomerates, mostly amorphous, with a complex chemical composition of sulfoxides. The results of the roasting experiments indicated that for a 75/25 weight ratio of the mixture of the copper concentrate/PR dust under 700℃, 15 minutes of roasting time with injection of air, the volatilization of arsenic reached 96% by weight. The arsenic concentration after the roasting process is less than 0.3% by weight. For a 5/95 mixture of sulfur/RP dust, at 650℃, the volatilization of arsenic reached a promissory result of 67%. Even that this study was carried out for a particular operation, the results have the potential to be extended to dust produced in the roasting of concen

关键词： Copper Smelter Dust Electrostatic Precipitators of Copper Removal of Arsenic Sulfidation Roasting Process Fluidized Bed Roasting

Pyrometallurgical Removal of Arsenic from Electrostatic Precipitators Dusts of Copper Smelting

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Journal of Minerals and Materials Characterization and Engineering 2021年第6期9卷 545-565页

作者： Hector Henao Ignacio Paredes rodrigo Diaz javier Ortiz Metallurgy Engineering Department Technical University Federico Santa María Av. Espa&#241 a 1680 Postal Code 2340000 Valparaíso Chile CODELCO Ministro Hales Division 48739 Antofagasta Chile

This work describes the experimental results of pyrometallurgical removing of arsenic from the dust collected in the electrostatic copper precipitators within the gas cleaning system of a Copper Flash Smelting Furnace. The generation of dust in the copper smelting worldwide ranges from 2 - 15 wt% per ton of a copper concentrate. In Chile, copper smelters produce approximately 110 kt/y of dust with a concentration of arsenic between 1 and 15 wt%. The dust is a complex of metals oxides and sulfurs with copper concentrations greater than 10 wt% and relatively high silver concentrations. Since its high arsenic concentration, it is difficult to recover valuable metals through hydrometallurgical processes or by direct recirculation of the dust in a smelting furnace. Thus, the development of pyrometallurgical processes aimed at reducing the concentration of arsenic in the dust (<0.5 wt%) is the main objective of this study, giving particular attention to the production of a suitable material to be recirculated in operations of copper smelting. The work provides a detailed characterization of the dust including the Quantitative Evaluation of Minerals by Scanning Electron Microscopy (QEMSCAN), Scanning Electron Microscope-Energy Dispersive X-ray Analysis (SEM/EDS), X-Ray Diffraction (XRD), the elemental chemical analysis using Atomic Adsorption (AAS), and X-Ray Fluorescence (X-RF). By considering that arsenic volatilization requires a process of sulfidation-decomposition-oxidation, this work seeks to explore the roasting of mixtures of copper concentrate/dust, sulfur/dust, and pyrrhotite/dust. By the elemental chemical analysis of the mixture after and before the roasting process, the degree of arsenic volatilization was determined. The results indicated the effects of parameters such as roasting temperature, gas flow, gas composition, and the ratio of mixtures (concentrate/dust, sulfur/dust, or pyrrhotite/dust) on the volatilization of arsenic. According to the findings, th

关键词： Copper Smelter Dust Electrostatic Precipitators of Copper Removal of Arsenic Sulfidation Roasting Process

Different patterns of intestinal response to injury after arterial,venous or arteriovenous occlusion in rats

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World Journal of Gastroenterology 2009年第31期15卷 3901-3907页

作者： Francisco javier Guzmán-de la Garza Carlos rodrigo Cámara-Lemarroy Gabriela Alarcón-Galván Paula Cordero-Pérez Linda Elsa Muoz-Espinosa Nancy Esthela Fernández-Garza Department of Physiology Autonomous University of Nuevo LeónSchool of Medicine Pathologic Anatomy and Cytopathology Service "José Eleuterio González" University Hospital Liver Unit Department of Internal MedicineAutonomous University of Nuevo LeónSchool of Medicine

AIM： To investigate the differences in injury patterns caused by arterial, venous or arteriovenous mesenteric occlusion. METHODS： Male Wistar rats were separated equally into four groups. Occlusion was performed by clamping the superior mesenteric artery （A）, the mesenteric vein （V） or both （AV） for 30 min, followed by 60 min of reperfusion. A control group received sham surgery only. Intestinal sections were examined for histological damage and serum tumor necrosis factor-α （TNF-α）, endothelin-1 （ET-1）, P-selectin, antithrombin Ⅲ （AT Ⅲ） and soluble intracellular adhesion molecule-1 （ICAM-1） concentrations were measured. RESULTS： All groups showed significant mucosal injury compared to controls. Furthermore, mucosal injury was significantly more severe in the V and AV groups compared to the A group （3.6 ± 0.55, 3.4 ± 0.55 and 2± 0.71, respectively, P = 0.01）. ICAM-1 was similarly elevated in all groups, with no significant differences between the groups. P-selectin levels were significantly elevated in the V and AV groups but not the A group （1.4 ± 0.5 ng/mL, 2.52 ± 0.9 ng/mL and 0.02± 0.01 ng/mL, respectively, P = 0.01） and ET-1 was significantly elevated in the A and V groups but not the AV group （0.32 ± 0.04 pg/mL, 0.36 ± 0.05 pg/mL and 0.29 ± 0.03 pg/mL, respectively, P = 0.01） compared to sham controls. ATⅢ levels were markedly depleted in the V and AV groups, but not in the A group （29.1 ± 5.2 pg/mL, 31.4 ±21.8 pg/mL and 55.8± 35.6 pg/mL, respectively, P = 0.01）, compared to controls. Serum TNF-α was significantly increased in all groups compared to sham controls （1.32 ± 0.87 ng/mL, 1.79 ± 0.20 ng/mL and 4.4 ± 0.69 ng/mL, for groups A, V and AV, respectively, P = 0.01）, with higher values in the AV group. CONCLUSION： Different patterns of response to ischemia/reperfusion are associated with venous, arterial or arteriovenous occlusion. Venous and arteriovenous occlusion was associated with the most severe alterations

关键词： Arterial occlusion Rat Intestine Ischemia/ reperfusion Venous occlusion