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The Nikola Tesla Constant and Its Relation to the Circumference Inscribed in a Square

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Journal of Applied Mathematics and Physics 2024年第1期12卷 277-283页

作者： Javier Mendoza Navarrete José Ismael Ojeda Campaña Huetzin Perez gabriel luna-sandoval Victor Verdugo Ricardo Jiménez Garcia Departamento de Matemáticas CBTis 256 DGETI Cabo San Lucas México División de Ingeniería en Sistemas Computacionales Tecnológico Nacional de México/ITES de Los Cabos Cabo San Lucas México DCI Departamento de Física Médica Universidad de Guanajuato León México Departamento de Ingeniería Industrial en Manufactura Universidad Estatal de Sonora Navojoa México Departamento de Eléctrica-Electrónica Tecnológico Nacional de México Campus Mexicali Mexicali México

This research work relates the surface of a square and the area circumscribed by a circle, resulting in a value called Nikola Tesla constant. This constant starts with the calculation of the areas of the square and the inscribed circle, giving a ratio of 9/40 and from which a residual area of the area proportions of the geometric figures described is obtained. Plotting smooth curves, particularly those in round shapes, can be represented efficiently with the use of Nikola Tesla constant, reducing complex mathematical calculus.

关键词： Tesla Numbers Prime Number Circle Binary Area

A Simple Detection System for Two Classical Sagnac Interferometer Configurations

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Engineering（科研） 2012年第12期4卷 903-907页

作者： gabriel Eduardo sandoval-Romero Enrique Francisco Pinzón-Escobar Centro de Ciencias Aplicadas y Desarrollo Tecnológico Universidad Nacional Autónoma de México México

Two interferometric systems were built, one in bulk optics and other one in fiber optics for showing the instrumentation stage designed for these devices, supported in a photodetector. This stage has a circuit for amplification, analog filtering and software for single channel data acquisition and digital filtering. Based on the Sagnac effect in bulk optics and in fiber optics, the Sagnac interferometer has many applications, nevertheless the methods of construction, design and instrumentation for the sensors used on both types of interferometers are well-known, but very common or general form, for this reason this work approaches some of the methodologies for the design and construction of these devices, obtaining higher sensitivity and better contribution in its respective interferometric paths. We used the simplest design for each interferometer, proposing the best detection limit for each one;to obtain the previous thing, we implement the three previous steps: amplifiers and analogous filters, software for filtering the digital sign. The data acquisition method used to allow us to obtain faster results, using the card of a PC, getting real time measurements and digital processing of the signal.

关键词： Sagnac Interferometer Instrumentation Photodetector Data Acquisition

Ecological-Genetic Studies and Conservation of Endemic <i>Quercus sideroxyla</i>(Trel.) in Central Mexico

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Natural Resources 2014年第9期5卷 442-453页

作者： Cecilia Alfonso-Corrado Ricardo Clark-Tapia Alejandro Monsalvo-Reyes Carlos Rosas-Osorio gabriel González-Adame Francisco Naranjo-luna Crystian-Sadiel Venegas-Barrera Jorge E. Campos Instituto de Estudios Ambientales Universidad de la Sierra Juárez Ixtlán de Juárez México InstitutoTecnológico de Ciudad Victoria Ciudad Victoria México Laboratorio de Bioquímica Molecular-Unidad de Biotecnología y Prototipos (UBIPRO) Fes-IZTACALA UNAM Tlalnepantla México

This study examines the distribution, ecology and genetic diversity of Quercus sideroxyla Humb. Bonpl, with an emphasis on its conservation on the Natural Protected Area of Sierra Fría in North Central Mexico. Twenty-nine locations were selected, and in each location, one plot of 1500 m2 was established. At every location, we obtained an abundance of Q. sideroxyla and a basal area for each individual tree, including geographical and climatological data. We used the Outlying Mean Index (OMI) to examine whether environmental conditions had a distributional effect on Q. sideroxyla populations and to obtain the static size population structure of the species. For the genetic analysis, we collected 18 adult individuals from each population, four polymorphic loci were used to estimate genetic diversity. Q. sideroxyla abundance was associated with narrow environmental conditions, especially when considering the topographical and meteorological environmental variables. The allelic richness value was 84 alleles (21 privatealleles), and the expected mean heterozygosity was 0.855 ± 0.009. The high vulnerability of the species to changes in the land use at the local scale and to global climatic changes increases the species’ susceptibility to local disappearance.

关键词： Ecology Genetic Diversity Local Conservation Niche Oaks

Alterations in fibrinolytic system proteins PAI-1,MMP-3,MMP-8,TIMP-1 and TIMP-2 in post-cholecystectomy bile duct injury

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Journal of Biomedical Science and Engineering 2013年第8期6卷 58-67页

作者： Jose Manuel Hermosillo-sandoval Luis Miguel Román-Pintos Adolfo Daniel Rodriguez-Carrizález Ernesto Germán Cardona-Munoz Fermin Paul Pacheco-Moisés Genaro gabriel Ortiz Alejandra Guillermina Miranda-Diaz Department of Surgery Specialties Hospital of the National Occidental Medical CentreSocial Security Institute of Mexico(Departamento de CirugíaHospital de Especialidades del Centro Médico Nacional de OccidenteInstituto Mexicano del Seguro Social)GuadalajaraMéxico University Health Sciences Centre University of Guadalajara(Centro Universitario de Ciencias de la SaludUniversidad de Guadalajara)GuadalajaraMéxico University Centre for Exact and Engineering Sciences University of Guadalajara(Centro Universitario de Ciencias Exactas e IngenieríasUniversidad de Guadalajara)GuadalajaraMéxico Pathology and Oxidative Stress Laboratory Division of NeurosciencesOccidental Biomedical Research CentreSocial Security Institute of Mexico(Laboratorio de Estrés Oxidativo&PatologíaDivision de NeurocienciasCentro de Investigacion Biomédica de OccidenteInstituto Mexicano del Seguro Social)GuadalajaraMéxico

Introduction: In bile duct injuries (BDI), cholestasis and cholangitis can alter the fibrinolytic system by promoting an increase of extracellular matrix depositions which favor an imbalance between metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). Materials and Methods: Levels of PAI-1, MMP-3, MMP-8, TIMP-1 and TIMP-2 in 35 patients with post-cholecystectomy BDI by complete biliary obstruction were measured and compared to a healthy control group. Sirius red staining and immune staining for MMP-3 and MMP-8 were also undertaken in liver biopsies. Results: Levels of PAI-1, TIMP-1, TIMP-2 and MMP-8 were higher in BDI than healthy controls: 15 ± 2 ng/mL vs 7.1 ± 2 ng/mL (p 0.024);539 ± 64 ng/mL vs 256 ± 13 ng/mL (p p p 2 vs. 22865.7 ± 3865 μm2 in healthy controls (p 2 vs. 30744.2 ± 5810.2 μm2 (p 2 vs. 116337.9 ± 24803.3 μm2 (p 0.55). These results suggest an imbalance between fibrogenic/fibrinolytic protein levels. Interestingly, expression of the fibrinolytic protein MMP-8 was increased in serum and liver biopsies in BDI. Conclusion: We found an imbalance of profibrogenic molecules which promote extracellular matrix deposition. The over-expression of fibrinolytic proteins such as MMP-8 could limit liver fibrosis, preventing hepatic dysfunction in post-cholecystectomy BDI.

关键词： Cholecystectomy Bile Duct Injury(BDI) Plasminogen Activator Inhibitor Type 1(PAI-1) Tissue Inhibitors of Metalloproteinases(TIMP’s) Metalloproteinases(MMP’s)

Endoscopic retrograde cholangiopancreatography drainage for palliation of malignant hilar biliary obstruction——stent-in-stent or side-by-side?A systematic review and meta-analysis

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World Journal of Hepatology 2021年第5期13卷 595-610页

作者： gabriel Mayo Vieira de Souza Igor Braga Ribeiro Mateus Pereira Funari Diogo Turiani Hourneaux de Moura Maria Vitória Cury Vieira Scatimburgo João Remíde Freitas Júnior Sergio A Sánchez-luna Renato Baracat Eduardo Turiani Hourneaux de Moura Wanderley Marques Bernardo Eduardo Guimarães Hourneaux de Moura Gastrointestinal Endoscopy Unit Hospital das Clínicas da Faculdade de Medicina da Universidade de São PauloSão Paulo 05403-010Brazil Division of Gastroenterology Hepatology and NutritionCenter for Advanced Therapeutic EndoscopyAllegheny Health NetworkPittsburghPA 15212United States Division of Gastroenterology and Hepatology Department of Internal MedicineBasil I.Hirschowitz Endoscopic Center of ExcellenceBirminghamAL 35294United States

BACKGROUND Biliary drainage,either by the stent-in-stent(SIS)or side-by-side(SBS)technique,is often required when treating a malignant hilar biliary obstruction(MHBO).Both methods differ from each other and have distinct *** To compare both techniques regarding their efficacy and safety in achieving drainage of *** A comprehensive search of multiple electronic databases(MEDLINE,Embase,LILACS,BIREME,Cochrane)was conducted and grey literature from their inception until December 2020 with no restrictions regarding the year of publication or language,since there was at least an abstract in *** included studies compared SIS and SBS techniques through endoscopic retrograde *** analyzed included technical and clinical success,early and late adverse events(AEs),stent patency,reintervention,and procedure-related *** Four cohort studies and one randomized controlled trial evaluating a total of 250 patients(127 in the SIS group and 123 in the SBS group)were included in this *** were no statistically significant differences between the two groups concerning the evaluated outcomes,except for stent patency,which was higher in the SIS compared with the SBS technique[mean difference(d)=33.31;95%confidence interval:9.73 to 56.90,I2=45%,P=0.006].CONCLUSION The SIS method showed superior stent patency when compared to SBS for achieving bilateral drainage in *** techniques are equivalent in terms of technical success,clinical success,rates of both early and late AEs,reintervention,and procedure-related mortality.

关键词： Endoscopic retrograde cholangiopancreatography Biliary tract neoplasms Biliary Hilar Stenting Drainage

Effects of vacuum-assisted closure and Drotrecogin alpha on inflammatory markers in severe acute pancreatitis

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Advances in Bioscience and Biotechnology 2013年第8期4卷 43-53页

作者： Oscar Arias-Carvajal José Manuel Hermosillo-sandoval Carlos Alberto Gutiérrez-Martínez Fermín Paul Pacheco-Moisés Genaro gabriel Ortiz Adolfo Daniel Rodríguez-Carrizalez Luis Miguel Román-Pintos Alejandra Guillermina Miranda-Díaz Department of Chemistry University of Guadalajara Guadalajara México Department of General Surgery Specialties Hospital National Occidental Medical Centre Social Security Institute of México Guadalajara México Department of Physiology University Health Sciences Centre University of Guadalajara Guadalajara México Intensive Care Unit Specialties Hospital National Occidental Medical Centre Social Security Institute of México Guadalajara México Occidental Biomedical Research Centre Social Security Institute of México Guadalajara México

In severe acute pancreatitis (SAP) inflammatory processes foster necrosis, cellular lysis and liberation of vasoactive substances associated with multiple organ failure. The effects of vacuum-assisted closure and Drotrecogin alpha on inflammatory cytokines were evaluated in SAP patients with infected necrosis. Methods: Forty-six patients were included in three groups: Group 1, necrosectomy and abdominal cavity washing;Group 2, necrosectomy plus vacuum-assisted closure (VAC), and Group 3, necrossectomy plus VAC plus Drotrecogin alpha. Immunoreactive IL-32, TNF-α, IL-6, TGF-β and IL-2 cytokines were quantified with ELISA method. Results: IL-32 was significantly increased in all patients, predominantly the non-survivor of Group 3 (p 0.0001). Group 2 maintained increased IL-32 levels throughout. Peak TNF-α was observed in non-survivors of Groups 1 and 2, with a frank tendency to decrease in Group 3. The IL-6 was increased, sustained throughout the study, peaking at the onset in non-survivors. At the end IL-6 tended to diminish, predominantly in survivors. TNF-α and IL-6 were significantly increased on hospitalization, with a maximum peak in non-survivors of all groups. Initial values of TGF-β were significantly increased in survivors of the three groups, and were significantly diminished in non-survivors;affecting pancreas regeneration and favoring systemic inflammation, with possible multiple-organ repercussions. IL-2 levels were elevated, predominantly in non-survivors of Group 1. There was positive correlation between the increase IL-32 and TNF-α, and negative correlation between the increase in TNF-α and decrease in TGF-β;and, a tendency for negative correlation between the IL-2 increased and TGF-β levels. Conclusion: We found a generalized, sustained inflammatory state that fosters a torpid outcome in SAP patients.

关键词： Severe Acute Pancreatitis Systemic Inflammation Proinflammatory Cytokines

Effects of intragastric balloon placement in metabolic dysfunctionassociated fatty liver disease: A systematic review and metaanalysis

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World Journal of Hepatology 2021年第7期13卷 815-829页

作者： João Remíde Freitas Júnior Igor Braga Ribeiro Diogo Turiani Hourneaux de Moura Vitor Massaro Takamatsu Sagae gabriel Mayo Vieira de Souza Guilherme Henrique Peixoto de Oliveira Sergio A Sánchez-luna Thiago Ferreira de Souza Eduardo Turiani Hourneaux de Moura Cláudia Pinto Marques Souza de Oliveira Wanderley Marques Bernardo Eduardo Guimarães Hourneaux de Moura Serviço de Endoscopia Gastrointestinal do Hospital das Clínicas HCFMUSP Departamento de GastroenterologiaFaculdade de MedicinaUniversidade de Sao PauloSao PauloSPBR Division of Gastroenterology and Hepatology Department of Internal MedicineBasil I.Hirschowitz Endoscopic Center of ExcellenceThe University of Alabama at BirminghamBirminghamAL 35294United States Department of Gastroenterology Hospital das Clínicas da Faculdade de Medicina da Universidade de São PauloSão Paulo 05403-010Brazil

BACKGROUND Metabolic dysfunction-associated fatty liver disease corresponds to a clinical entity that affects liver function triggered by the accumulation of fat in the liver and is linked with metabolic *** To evaluate the effects of the intragastric balloon(IGB)in patients with metabolic dysfunction-associated fatty liver disease through the assessment of liver enzymes,imaging and several metabolic *** A comprehensive search was done of multiple electronic databases(MEDLINE,EMBASE,LILACS,Cochrane and Google Scholar)and grey literature from their inception until February *** criteria involved patients with a body mass index>25 kg/m2 with evidence or previous diagnosis of hepatic *** analyzed before and after 6 mo of IGB removal were alanine aminotransferase(IU/L),gamma-glutamyltransferase(IU/L),glycated hemoglobin(%),triglycerides(mg/dL),systolic blood pressure(mmHg),homeostatic model assessment,abdominal circumference(cm),body mass index(kg/m2)and liver volume(cm3).RESULTS Ten retrospective cohort studies evaluating a total of 508 patients were *** 6 mo of IGB placement,this significantly reduced alanine aminotransferase[mean difference(MD):10.2,95%confidence interval(CI):8.12-12.3],gammaglutamyltransferase(MD:9.41,95%CI:6.94-11.88),glycated hemoglobin(MD:0.17%,95%CI:0.03-0.31),triglycerides(MD:38.58,95%CI:26.65-50.51),systolic pressure(MD:7.27,95%CI:4.79-9.76),homeostatic model assessment(MD:2.23%,95%CI:1.41-3.04),abdominal circumference(MD:12.12,95%CI:9.82-14.41)and body mass index(MD:5.07,95%CI:4.21-5.94).CONCLUSION IGB placement showed significant efficacy in improving alanine aminotransferase and gamma-glutamyltransferase levels in patients with metabolic dysfunctionassociated fatty liver disease as well as improving metabolic markers related to disease progression.

关键词： Intragastric balloon Metabolic dysfunction-associated fatty liver disease Homeostatic model assessment Abdominal circumference Body mass index