70 research outputs found

    LABORATORIO VIRTUAL DE DESTILACIÓN QUÍMICA

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    Se describe el proceso que se siguió para la construcción de un laboratorio virtual de destilación simple apoyado en un sistema de captura de movimiento

    Modelo de la marcha bipeda humana usando modelica

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    his paper describes research to generate an application where human bipedal gait displayed, using the Modelica 2.1.2 ® software and tools for visualization in 3 dimensions. This provides a physical- mathematical model which is configured own systems and software subsystems. For the simulation, we took into account the basic operation of the walk that makes a biped robot theory and their respective direct and inverse kinematics as well as the actions of proportional-derivative control (PD), proportional-integral (PI) and proportional-integral-derivative (PID) closed loop tuning and specifications for adjusting the angle of the leg joints and maintain a level ground on which to perform the displacement of the object, the product is expected to serve as based educational program developed based on, for the design and implementation of advanced devices : whether robots that emulate the human gait, for entertainment and even virtual reality for human use, or to create a prosthesis control that allows a disabled person have the ability to walk.Este artículo describe la investigación para generar un aplicativo donde se visualiza la marcha bípeda humana, haciendo uso del software Modelica 2.1.2 ® y sus herramientas para la visualización en tres dimensiones. Para ello se desarrolló un modelo físico-matemático con el cual se configuraron los sistemas y subsistemas propios del software. Para la simulación se tuvo en cuenta el funcionamiento básico de la caminata que efectúa un robot bípedo y su respectiva teoría de cinemática inversa y directa, al igual que las acciones de controles proporcionalderivativa (PD), proporcional-integral (PI) y proporcional-integral-derivativa (PID) en lazo cerrado, y especificaciones de sintonización para la regulación de ángulo de las articulaciones de las piernas y mantener un nivel del piso sobre el cual se realice el desplazamiento del objeto. Esta investigación permitió obtener la visualización de la caminata bípeda en un plano, observando que el control tomando como referencia la posición angular, es uno de los métodos más efectivos en el momento de generar los pasos del robot, pues básicamente se calculan y se controlan las fuerzas que se interponen en este proceso

    Inflammation but Not Endothelial Dysfunction Is Associated with the Severity of Coronary Artery Disease in Dyslipidemic Subjects

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    Introduction. Endothelial dysfunction and inflammation play a key role in the development of atherosclerosis. The present study evaluated endothelial function, inflammatory parameters, and carotid intima-media thickness (IMT) in dyslipidemic patients with or without coronary artery disease (CAD). Methods. Metabolic profile and inflammatory parameters were determined in dyslipidemic patients with (+CAD, n = 33) and without (−CAD, n = 69) symptomatic CAD. Endothelial function was evaluated by flow mediated dilatation (FMD) and plasma concentration of nitrites and nitrates. Carotid IMT was measured by ultrasound. Results. No significant differences were observed in anthropometric hemodynamic or metabolic parameters between the groups. After adjusting by age and medication usage, some inflammatory markers were significantly higher in +CAD; however no significant differences in FMD or plasma levels of nitrites were observed. Conclusions. In subjects with dyslipidemia, the presence of CAD is associated with an elevation of certain inflammatory markers and carotid IMT but not with further endothelial dysfunction

    Sunflower meal and supplementation of enzyme complex in diets for growing and finishing pigs

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    Este estudo teve como objetivo avaliar a inclusão de farelo de girassol e a suplementação de complexo enzimático sobre os parâmetros de desempenho e características de carcaça de suínos, dos 30 aos 100 kg de peso vivo. Foram utilizados 96 suínos com peso vivo médio de 32,19±3,27 kg, distribuídos em um delineamento experimental de blocos casualizados, em esquema fatorial 4 x 2 (quatro níveis de farelo de girassol-FG: 0, 8, 16 e 24% com ou sem inclusão do complexo enzimático-CE), com seis repetições e dois animais por unidade experimental. As variáveis analisadas foram o consumo de ração (kg), o ganho de peso (kg), a conversão alimentar (kg/ kg), a espessura de toucinho (mm), a musculosidade (kg), o peso da carcaça quente (%), a porcentagem de carne magra na carcaça (%), a quantidade de carne magra na carcaça (kg). Não houve nenhuma interação entre os fatores para nenhuma das variáveis estudadas. A conversão alimentar dos animais dos 30 aos 70 kg de peso foi diminuída pela inclusão do CE, porém não afetou os parâmetros de carcaça. Níveis crescentes de FG na ração apresentaram efeito quadrático sobre o ganho de peso dos animais e sobre a espessura de toucinho, com valores máximos dessas variáveis em 7,26% e 8,16% de inclusão do FG, respectivamente. Aiming to evaluate the performance of pigs from 30 to 100 kg of live a total of 96 pigs with average live weight of 32.19±3.27 kg were distributed in randomized blocks design in a 4 × 2 (four levels of SM: 0, 8, 16 and 24%; with or without inclusion of EC)  factorial arrangement with six replicates and two animals per experimental unit. The parameters analyzed were feed intake (kg), weight gain (kg), feed conversion (kg/kg), backfat thickness (mm), carcass muscularity (kg), hot carcass weight (%), percentage of lean meat in the carcass (%), and quantity of lean meat in the carcass (kg). There was no interaction between EC and SM levels in the diet. The addition of EC in the diet affected the performance of the animals, but not carcass characteristics. Feed conversion of animals from 30 to 70 kg weight was improved by the inclusion of EC. The increasing levels of SM in the diet presented quadratic effect on weight gain and on backfat thickness, with inclusion points of SM that promoted maximum values of these parameters of 7.26% and 8.16%, respectively.

    Sunflower meal and supplementation of enzyme complex in diets for growing and finishing pigs

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    Aiming to evaluate the performance of pigs from 30 to 100 kg of live a total of 96 pigs with average live weight of 32.19±3.27 kg were distributed in randomized blocks design in a 4 × 2 (four levels of SM: 0, 8, 16 and 24%; with or without inclusion of EC)  factorial arrangement with six replicates and two animals per experimental unit. The parameters analyzed were feed intake (kg), weight gain (kg), feed conversion (kg/kg), backfat thickness (mm), carcass muscularity (kg), hot carcass weight (%), percentage of lean meat in the carcass (%), and quantity of lean meat in the carcass (kg). There was no interaction between EC and SM levels in the diet. The addition of EC in the diet affected the performance of the animals, but not carcass characteristics. Feed conversion of animals from 30 to 70 kg weight was improved by the inclusion of EC. The increasing levels of SM in the diet presented quadratic effect on weight gain and on backfat thickness, with inclusion points of SM that promoted maximum values of these parameters of 7.26% and 8.16%, respectively.

    Gender Difference in the Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry

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    Background. Several reports have demonstrated the impact of the COVID-19 pandemic on the management and outcome of patients with ST-segment elevation myocardial infarction (STEMI). The aim of the current analysis is to investigate the potential gender difference in the effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI patients within the ISACS-STEMI COVID-19 Registry. Methods. This retrospective multicenter registry was performed in high-volume primary percutaneous coronary intervention (PPCI) centers on four continents and included STEMI patients undergoing PPCIs in March–June 2019 and 2020. Patients were divided according to gender. The main outcomes were the incidence and timing of the PPCI, (ischemia time ≥ 12 h and door-to-balloon ≥ 30 min) and in-hospital or 30-day mortality. Results. We included 16683 STEMI patients undergoing PPCIs in 109 centers. In 2020 during the pandemic, there was a significant reduction in PPCIs compared to 2019 (IRR 0.843 (95% CI: 0.825–0.861, p < 0.0001). We did not find a significant gender difference in the effects of the COVID-19 pandemic on the numbers of STEMI patients, which were similarly reduced from 2019 to 2020 in both groups, or in the mortality rates. Compared to prepandemia, 30-day mortality was significantly higher during the pandemic period among female (12.1% vs. 8.7%; adjusted HR [95% CI] = 1.66 [1.31–2.11], p < 0.001) but not male patients (5.8% vs. 6.7%; adjusted HR [95% CI] = 1.14 [0.96–1.34], p = 0.12). Conclusions. The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures similarly observed in both genders. Furthermore, we observed significantly increased in-hospital and 30-day mortality rates during the pandemic only among females. Trial registration number: NCT 04412655

    Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI : Results of the ISACS-STEMI COVID-19 Registry

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    Background: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March–June 2019 and 2020. Patients were divided according to age (< or ≥75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825–0.861, p < 0.0001). We found a significant agerelated reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24–1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05–1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic

    Age-Related Effects of COVID-19 Pandemic on Mechanical Reperfusion and 30-Day Mortality for STEMI: Results of the ISACS-STEMI COVID-19 Registry

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    Background: The constraints in the management of patients with ST-segment elevation myocardial infarction (STEMI) during the COVID-19 pandemic have been suggested to have severely impacted mortality levels. The aim of the current analysis is to evaluate the age-related effects of the COVID-19 pandemic on mechanical reperfusion and 30-day mortality for STEMI within the registry ISACS-STEMI COVID-19. Methods: This retrospective multicenter registry was performed in high-volume PPCI centers on four continents and included STEMI patients undergoing PPCI in March-June 2019 and 2020. Patients were divided according to age (= 75 years). The main outcomes were the incidence and timing of PPCI, (ischemia time longer than 12 h and door-to-balloon longer than 30 min), and in-hospital or 30-day mortality. Results: We included 16,683 patients undergoing PPCI in 109 centers. In 2020, during the pandemic, there was a significant reduction in PPCI as compared to 2019 (IRR 0.843 (95%-CI: 0.825-0.861, p < 0.0001). We found a significant age-related reduction (7%, p = 0.015), with a larger effect on elderly than on younger patients. Furthermore, we observed significantly higher 30-day mortality during the pandemic period, especially among the elderly (13.6% vs. 17.9%, adjusted HR (95% CI) = 1.55 [1.24-1.93], p < 0.001) as compared to younger patients (4.8% vs. 5.7%; adjusted HR (95% CI) = 1.25 [1.05-1.49], p = 0.013), as a potential consequence of the significantly longer ischemia time observed during the pandemic. Conclusions: The COVID-19 pandemic had a significant impact on the treatment of patients with STEMI, with a 16% reduction in PPCI procedures, with a larger reduction and a longer delay to treatment among elderly patients, which may have contributed to increase in-hospital and 30-day mortality during the pandemic

    Impact of chronic obstructive pulmonary disease on short-term outcome in patients with ST-elevation myocardial infarction during COVID-19 pandemic: insights from the international multicenter ISACS-STEMI registry

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    Background Chronic obstructive pulmonary disease (COPD) is projected to become the third cause of mortality worldwide. COPD shares several pathophysiological mechanisms with cardiovascular disease, especially atherosclerosis. However, no definite answers are available on the prognostic role of COPD in the setting of ST elevation myocardial infarction (STEMI), especially during COVID-19 pandemic, among patients undergoing primary angioplasty, that is therefore the aim of the current study. Methods In the ISACS-STEMI COVID-19 registry we included retrospectively patients with STEMI treated with primary percutaneous coronary intervention (PCI) between March and June of 2019 and 2020 from 109 high-volume primary PCI centers in 4 continents. Results A total of 15,686 patients were included in this analysis. Of them, 810 (5.2%) subjects had a COPD diagnosis. They were more often elderly and with a more pronounced cardiovascular risk profile. No preminent procedural dissimilarities were noticed except for a lower proportion of dual antiplatelet therapy at discharge among COPD patients (98.9% vs. 98.1%, P = 0.038). With regards to short-term fatal outcomes, both in-hospital and 30-days mortality occurred more frequently among COPD patients, similarly in pre-COVID-19 and COVID-19 era. However, after adjustment for main baseline differences, COPD did not result as independent predictor for in-hospital death (adjusted OR [95% CI] = 0.913[0.658-1.266], P = 0.585) nor for 30-days mortality (adjusted OR [95% CI] = 0.850 [0.620-1.164], P = 0.310). No significant differences were detected in terms of SARS-CoV-2 positivity between the two groups. Conclusion This is one of the largest studies investigating characteristics and outcome of COPD patients with STEMI undergoing primary angioplasty, especially during COVID pandemic. COPD was associated with significantly higher rates of in-hospital and 30-days mortality. However, this association disappeared after adjustment for baseline characteristics. Furthermore, COPD did not significantly affect SARS-CoV-2 positivity. Trial registration number: NCT 04412655 (2nd June 2020)

    Impact of Smoking Status on Mortality in STEMI Patients Undergoing Mechanical Reperfusion for STEMI : Insights from the ISACS–STEMI COVID-19 Registry

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    The so-called “smoking paradox”, conditioning lower mortality in smokers among STEMI patients, has seldom been addressed in the settings of modern primary PCI protocols. The ISACS– STEMI COVID-19 is a large-scale retrospective multicenter registry addressing in-hospital mortality, reperfusion, and 30-day mortality among primary PCI patients in the era of the COVID-19 pandemic. Among the 16,083 STEMI patients, 6819 (42.3%) patients were active smokers, 2099 (13.1%) previous smokers, and 7165 (44.6%) non-smokers. Despite the impaired preprocedural recanalization (p < 0.001), active smokers had a significantly better postprocedural TIMI flow compared with nonsmokers (p < 0.001); this was confirmed after adjustment for all baseline and procedural confounders, and the propensity score. Active smokers had a significantly lower in-hospital (p < 0.001) and 30-day (p < 0.001) mortality compared with non-smokers and previous smokers; this was confirmed after adjustment for all baseline and procedural confounders, and the propensity score. In conclusion, in our population, active smoking was significantly associated with improved epicardial recanalization and lower in-hospital and 30-day mortality compared with previous and non-smoking histor
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