369 research outputs found

    Nuevos valores críticos de F y su uso en las pruebas ANOVA y F de Fisher para evaluar el material de referencia geoquímica del granito G-2 (U.S.A.) y rocas ígneas de la Provincia Alcalina Oriental (México)

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    Monte Carlo method was used to simulate precise and accurate critical values (with 2 to 7 decimal places) of Fisher´s F test for degrees of freedom (ν1 and ν2) of up to 2000 and confidence levels of 20% to 99.9% for two-sided or two-tailed test (or equivalently to 60% to 99.95% for one-sided or one-tailed test). Unlike the existing literature, we present 15 new critical value tables along with 15 additional tables of the error estimates of individual values. For the two degrees of freedom – horizontal (ν1) as well as vertical (ν2) –the critical values orrespond to 1(1)30(5)100(10)160(20)200(50)400(100)1000 and 6(1)30(5)100(10)160(20)200(50)400 (100)1000(200)2000, respectively, where the numbers before and after the parenthesis are the initial and final values for which critical values were simulated and the numbers in parenthesis indicate the step size how the initial value of degrees of freedom approached to the final one. Thus these critical values consist of 62x62 values for each of the eleven confidence levels. Even though a large number (3844 for each confidence level, amounting to a total of 42284 values for all confidence levels) of new values of F were simulated, values do not exist for many different degrees of freedom in the range of 1-2000. This problem of unavailable critical values was resolved by evaluating regression models based on simple polynomial functions as well as those involving logtransformation of the independent variable. New best-fit equations were thus proposed to estimate the not-tabulated critical values as well as for the estimation of probability of calculated F value. This methodology of log transformations should be useful also for other kinds of applications involving polynomial fitting. We compared these simulated results with commercial as well as freely available software. The new precise and accurate critical values were used to illustrate the application of analysis of variance (ANOVA) and Fisher´s F tests to geochemical data for international geochemical reference material granite G-2 from U.S.A. We also present the methodology to statistically compare geochemical data for ultrabasic, basic and intermediate magmas from eight regions of the Eastern Alkaline Province of Mexico and U.S.A. Finally, we use these as well as the discordant outlier-free data for ultrabasic and basic rocks in multi-dimensional discrimination diagrams to explore the tectonic setting for this volcanic province, which was inferred to be mainly an extensional zone or a continental rift.El método de Monte Carlo fue usado para simular valores críticos precisos y exactos (con 2 a 7 puntos decimales) de la prueba F de Fisher para los grados de libertad (ν1 y ν2) hasta 2000 y niveles de confianza de 20% a 99.9% para la prueba de dos colas o ambos lados (o en forma equivalente de 60% a 99.95% para la prueba de una cola o un sólo lado). A diferencia de la literatura existente, presentamos 15 nuevas tablas de valores críticos junto con otras 15 tablas adicionales con las estimaciones de errores de los valores individuales. Para los grados de libertad, horizontal (ν1) y vertical (ν2), los valores críticos corresponden a 1(1)30(5)100 (10)160(20)200(50)400(100)1000 y 6(1)30(5)100(10)160(20)200(50)400(100)1000(200)2000, respectivamente, donde los números antes y después del paréntesis son los valores iniciales y finales para los cuales los valores críticos fueron simulados y el número en el paréntesis indica el escalón cómo el valor inicial del grados de libertad llega al valor final. De esta manera, estos consisten en 62x62 valores para cada nivel de confianza. A pesar de que un gran número (3844 para cada nivel de confianza, lo que equivale a un total de 42284 valores para todos los niveles de confianza) de nuevos valores de F fueron simulados, no se dispone de valores correspondientes a muchos grados de libertad intermedios entre el 1 y 2000. Este problema de valores críticos no-disponibles fue resuelto mediante la evaluación de modelos de regresión basados en métodos convencionales de polinomios así como aquellos con las transformaciones logarítmicas de la variable independiente. La metodología de transformaciones logarítmicas debe ser útil también para otros tipos de aplicaciones de ajustes polinomiales. Se proponen nuevas ecuaciones para la estimación de los valores críticos no tabulados, así como para la estimación de la probabilidad del valor de F calculado. Así mismo, comparamos los resultados con software comercial y de libre acceso. Estos nuevos valores críticos más precisos y exactos fueron usados para ilustrar la aplicación de las pruebas de análisis de varianza (ANOVA) y F de Fisher a los datos geoquímicos de material internacional de referencia geoquímica granito G-2 de E.U.A. También presentamos la metodología de comparar estadísticamente los datos geoquímicos para magmas ultrabásicos, básicos e intermedios de ocho regiones de la Provincia Alcalina Oriental de México y E.U.A. Finalmente, usamos estos datos y los libres de valores extremos discordantes para rocas ultrabásicas y básicas en diagramas tectonomagmáticos multi-dimensionales para explorar el ambiente tectónico de esta provincia volcánica, mismo que fue inferido principalmente como una zona de extensión o rift continental

    Fuzzy Inference System-based Geo Visualization Tool Development for Yamuna River Water Quality Analysis

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    An analysis of Yamuna River Water Quality through the use of a Fuzzy Inference System illustrates the capabilities of artificial intelligence in the development of novel Geovisualizer. Numerous Geovisualizer systems exist worldwide, but none can estimate water quality with artificial intelligence instead, relying on statistical data that vary with the scenario and have dubious accuracy. This logic has not been applied to the classification of Water Quality Standards by any designated government agency for water quality monitoring and management. A robust and integrated application program interface is developed by combining MongoDB and JavaScript library utilities Leaflet.js, Node.js, ArcGIS, ERDAS Imagine, and Fuzzy Algorithm; embellished with HTML and CSS. The Yamuna River is considered for the spatial-temporal aspect of the application. End users can authenticate with JSON web tokens. Spatial and non-spatial data are visualized by Inverse Distance Weighted Interpolation technique of ArcGIS. The Water Quality Index can be calculated using combinations of critically chosen input parameters integrated through frontend and backend functionality that incorporates fuzzy set theory with input from a Geovisualizer database and frontend platforms; not available on the existing geovisualization platform. With its scalability, extensibility, and execution speed, the resultant 121RRwebgis Geovisualizer outperforms conventional applications. Thus, a robust platform for global researchers is developed

    Fuzzy modeling for the spread of influenza virus and its possible control

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    In this paper, we analyze a model of Influenza spread with an asymptotic transmission rate, wherein the disease transmission rate and death rate are considered as fuzzy sets. Comparative studies of the equilibrium points of the disease for the classical and fuzzy models are performed. Using the concept of probability measure and fuzzy expected value, we obtain the fuzzy basic reproduction number for groups of infected individuals with different virus loads. Further, a basic reproduction number for the classical and the fuzzy model are compared. Finally, a program based on the basic reproduction value of disease control is suggested and the numerical simulations are carried out to illustrate the analytical results

    Sodium-Glucose Cotransporter 2 Inhibitors and the Risk of Pneumonia and Septic Shock

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    CONTEXT: Individuals with type 2 diabetes mellitus (DM) have an increased risk of pneumonia and septic shock. Traditional glucose-lowering drugs have recently been found to be associated with a higher risk of infections. It remains unclear whether sodium-glucose cotransporter 2 inhibitors (SGLT2is), which have pleiotropic/anti-inflammatory effects, may reduce the risk of pneumonia and septic shock in DM. METHODS: MEDLINE, Embase, and ClinicalTrials.gov were searched from inception up to May 19, 2022, for randomized, placebo-controlled trials of SGLT2i that included patients with DM and reported outcomes of interest (pneumonia and/or septic shock). Study selection, data extraction, and quality assessment (using the Cochrane Risk of Bias Assessment Tool) were conducted by independent authors. A fixed-effects model was used to pool the relative risk (RRs) and 95% CI across trials. RESULTS: Out of 4568 citations, 26 trials with a total of 59 264 patients (1.9% developed pneumonia and 0.2% developed septic shock) were included. Compared with placebo, SGLT2is significantly reduced the risk of pneumonia (pooled RR 0.87, 95% CI 0.78-0.98) and septic shock (pooled RR 0.65, 95% CI 0.44-0.95). There was no significant heterogeneity of effect size among trials. Subgroup analyses according to the type of SGLT2i used, baseline comorbidities, glycemic control, duration of DM, and trial follow-up showed consistent results without evidence of significant treatment-by-subgroup heterogeneity (all P(heterogeneity) > .10). CONCLUSION: Among DM patients, SGLT2is reduced the risk of pneumonia and septic shock compared with placebo. Our findings should be viewed as hypothesis generating, with concepts requiring validation in future studies

    Study of Cabibbo Suppressed Decays of the Ds Charmed-Strange Meson involving a KS

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    We study the decay of Ds meson into final states involving a Ks and report the discovery of Cabibbo suppressed decay modes Ds -> Kspi-pi+pi+ (179 +/- 36 events) and Ds -> Kspi+ (113 +/-26 events). The branching ratios for the new modes are Gamma(Ds -> Kspi-pi+pi+)/Gamma(Ds -> KsK-pi+pi+) = 0.18 +/- 0.04 +/- 0.05 and Gamma(Ds -> Kspi+)/Gamma(Ds -> KsK+) = 0.104 +/- 0.024 +/- 0.013.Comment: 11 pages, 6 figure

    Effects of liraglutide on cardiovascular outcomes in patients with type 2 diabetes mellitus with or without history of myocardial infarction or stroke: Post hoc analysis from the leader trial

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    Background: The glucagon-like peptide-1 analog liraglutide reduced cardiovascular events and mortality in patients with type 2 diabetes mellitus in the LEADER trial (Liraglutide and Cardiovascular Outcomes in Type 2 Diabetes). In a post hoc analysis, we evaluated the efficacy of liraglutide in those with and without a history of myocardial infarction (MI) and/or stroke. Methods: LEADER was a randomized trial of liraglutide (1.8 mg or maximum tolerated dose) versus placebo in 9340 patients with type 2 diabetes mellitus and high cardiovascular risk, with a median follow-up of 3.8 years. The primary outcome was a composite of cardiovascular death, nonfatal MI, or nonfatal stroke (major adverse cardiovascular events). Risk groups in this post hoc analysis were defined by history of MI/stroke, established atherosclerotic cardiovascular disease without MI/stroke, or cardiovascular risk factors alone. Results: Of the 9340 patients, 3692 (39.5%) had a history of MI/stroke, 3083 (33.0%) had established atherosclerotic cardiovascular disease without MI/stroke, and 2565 (27.5%) had risk factors alone. Major adverse cardiovascular events occurred in 18.8% of patients with a history of MI/stroke (incidence rate, 5.0 per 100 patient-years), 11.6% of patients with established atherosclerotic cardiovascular disease without MI/stroke (incidence rate, 3.0 per 100 patient-years), and 9.8% of patients with cardiovascular risk factors alone (incidence rate, 2.6 per 100 patient-years). Liraglutide reduced major adverse cardiovascular events in patients with a history of MI/stroke (322 of 1865 [17.3%] versus 372 of 1827 patients [20.4%]; hazard ratio, 0.85; 95% CI, 0.73-0.99) and in those with established atherosclerotic cardiovascular disease without MI/stroke (158 of 1538 [10.3%] versus 199 of 1545 patients [12.9%]; hazard ratio, 0.76; 95% CI, 0.62-0.94) compared with placebo. In patients with risk factors alone, the hazard ratio for liraglutide versus placebo was 1.08 (95% CI, 0.84-1.38, Pinteraction=0.11). Similar results were seen for secondary outcomes across risk groups. Conclusions: In this post hoc analysis of patients with type 2 diabetes mellitus and high cardiovascular risk, liraglutide reduced cardiovascular outcomes both in patients with a history of MI/stroke and in those with established atherosclerotic cardiovascular disease without MI/stroke. The cardiovascular effect appeared neutral in patients with cardiovascular risk factors alone

    Global surveillance of cancer survival 1995-2009: analysis of individual data for 25,676,887 patients from 279 population-based registries in 67 countries (CONCORD-2)

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    BACKGROUND: Worldwide data for cancer survival are scarce. We aimed to initiate worldwide surveillance of cancer survival by central analysis of population-based registry data, as a metric of the effectiveness of health systems, and to inform global policy on cancer control. METHODS: Individual tumour records were submitted by 279 population-based cancer registries in 67 countries for 25·7 million adults (age 15-99 years) and 75,000 children (age 0-14 years) diagnosed with cancer during 1995-2009 and followed up to Dec 31, 2009, or later. We looked at cancers of the stomach, colon, rectum, liver, lung, breast (women), cervix, ovary, and prostate in adults, and adult and childhood leukaemia. Standardised quality control procedures were applied; errors were corrected by the registry concerned. We estimated 5-year net survival, adjusted for background mortality in every country or region by age (single year), sex, and calendar year, and by race or ethnic origin in some countries. Estimates were age-standardised with the International Cancer Survival Standard weights. FINDINGS: 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005-09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15-19% in North America, and as low as 7-9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10-20% between 1995-99 and 2005-09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995-99 and 2005-09 have generally been slight. For women diagnosed with ovarian cancer in 2005-09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005-09 was high (54-58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18-23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease. INTERPRETATION: International comparison of survival trends reveals very wide differences that are likely to be attributable to differences in access to early diagnosis and optimum treatment. Continuous worldwide surveillance of cancer survival should become an indispensable source of information for cancer patients and researchers and a stimulus for politicians to improve health policy and health-care systems

    Anemia prevalence in women of reproductive age in low- and middle-income countries between 2000 and 2018

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    Anemia is a globally widespread condition in women and is associated with reduced economic productivity and increased mortality worldwide. Here we map annual 2000–2018 geospatial estimates of anemia prevalence in women of reproductive age (15–49 years) across 82 low- and middle-income countries (LMICs), stratify anemia by severity and aggregate results to policy-relevant administrative and national levels. Additionally, we provide subnational disparity analyses to provide a comprehensive overview of anemia prevalence inequalities within these countries and predict progress toward the World Health Organization’s Global Nutrition Target (WHO GNT) to reduce anemia by half by 2030. Our results demonstrate widespread moderate improvements in overall anemia prevalence but identify only three LMICs with a high probability of achieving the WHO GNT by 2030 at a national scale, and no LMIC is expected to achieve the target in all their subnational administrative units. Our maps show where large within-country disparities occur, as well as areas likely to fall short of the WHO GNT, offering precision public health tools so that adequate resource allocation and subsequent interventions can be targeted to the most vulnerable populations.Peer reviewe
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