Invariance principles for switched systems with restrictions

In this paper we consider switched nonlinear systems under average dwell time switching signals, with an otherwise arbitrary compact index set and with additional constraints in the switchings. We present invariance principles for these systems and derive by using observability-like notions some convergence and asymptotic stability criteria. These results enable us to analyze the stability of solutions of switched systems with both state-dependent constrained switching and switching whose logic has memory, i.e., the active subsystem only can switch to a prescribed subset of subsystems.Comment: 29 pages, 2 Appendixe

Efectividad cualitativa del ganado caprino en la dispersión de especies de frutos secos y carnosos

[ES] mediterráneo: Cistus salviifolius, C. libanotis, Halimum halimifolium H. calycinum, Myrtus communis, Phillyrea angustifolia, Pistacia lentiscus y Rhamnus lycioides. Frutos de estas especies fueron ofrecidos a seis cabras estabuladas individualmente. Tras la ingestión, se procedió a recoger las heces a intervalos de 24 horas. En las heces recuperadas, se determinó el porcentaje de pérdida de semillas (masticación y digestión), distribución de la recuperación de las semillas en el tiempo y la eficacia germinativa tras el paso por el tracto digestivo. Menos del 30% de las semillas ingeridas fueron recuperadas, con diferencias significativas entre las especies. C. salviifolius presentó el mayor porcentaje de recuperación (casi 30%) y P. lentiscus el menor (0%). Esta tasa de recuperación estuvo significativamente relacionada positivamente con la dureza de las semillas. En la mayoría de las especies, la máxima tasa de recuperación se dio entre las 24-72 horas tras la ingestión. El paso por el intestino de las cabras aumentó significativamente la germinación de C. salviifolius, H. halimifolium, H. calycinum y P. angustifolia. Los resultados de este estudio pusieron de manifiesto que el ganado caprino puede favorecer la dispersión de la mayoría de las semillas de especies cistáceas estudiadas e inhibir la dispersión de semillas de frutos carnosos. El conocimiento de los mecanismos de dispersión por ungulados generalistas son aspectos importantes a tener en cuenta en los planes de gestión, restauración y conservación de los ecosistemas Mediterráneos[EN] We evaluated the role of domestic goats as seed dispersers of eight representative Mediterranean shrub species (Cistus salviifolius, C. libanotis, Halimum halimifolium, H. calycinum, Myrtus communis, Phillyrea angustifolia, Pistacia lentiscus and Rhamnus lycioides). Six female goats of similar size and age were fed with fruits of study species. Following fruits ingestion by goats, total faeces were collected at 24-h intervals. The seeds retrieved were tested for germination and viability, along with seeds not eaten by the goats. Less than 30% of the seeds eaten were retrieved from the dung, with significant differences between species. C. salviifolius showing the maximum recovery percentage (30%), and P. lentiscus the minimum (0%). Seed recovery was significantly related to seed hardness. In most species, the maximum amount of seeds recovered occurred 24-72 h after ingestion. The passage through the goat gut significantly increased seed germination in C. salviifolius, H. halimifolium, H. calycinum and P. angustifolia. The results of this study show that goats can potentially favour (Cistaceae) or inhibit (fleshy fruits) seed dispersal of browsed Mediterranean shrub species. Therefore, these results should be considered when developing conservation and restoration plans of natural vegetation in Mediterranean areasPeer reviewe

Comparison of effectiveness between a conventional catheter and a manual commercial catheter: randomized trial of simulation of intraosseous access in a biological model

Introduction: In the emergency services an action of paramount importance in critically ill patients is to obtain an early vascular access. When vascular access is not established, an intraosseous route should be obtained; otherwise, the mortality of these critically ill patients is almost 100%. In Colombia, the intraosseous access is not used because of the high costs of the devices and the lack of training of the healthcare staff to conduct the procedure.Objective: To determine the efficacy of a low-cost device to establish intraosseous access.Materials and methods: Quantitative approach, experimental design in a simulated environment with chicken tarsus and metatarsus. An analysis was conducted using frequency tables and central tendency measurements. Likewise, further analyses were done using Fisher's exact test, Chi2, and Mann-Whitney test.Results: A total of 99% of the procedures were successful with both catheters. The average time for intraosseous access was 6.6 seconds with Insyte 14 catheter and 4.7 seconds with Din 1515x Illinois Desch device (P=0.001). There were no significant differences in the number of attempts to secure a successful intraosseous access using any of the 2 devices (P=0.56).Conclusion: There was no significant difference between the Ci 14 and the Si 14 catheter to establish a successful intraosseous access in the chicken tarsus and metatarsus in a simulated environment. © 2019 Sociedad Colombiana de Anestesiología y Reanimación (S.C.A.R.E.)

Utilización de la cestilla de Moss en el tratamiento de fracturas patológicas vertebrales

Las fracturas patológicas vertebrales pueden inducir radículo o mielopatía compresiva, inestabilidad y deformidad, de tal forma que el objetivo del tratamiento consistiría en restablecer lo más rápidamente posible la anatomía y función. En este sentido la utilización de una malla cilindrica de titanio como la «cestilla de Moss» consigue una estabilidad inmediata y permite la carga precoz. Presentamos un estudio retrospectivo de 6 pacientes afectos de fractura patológica vertebral intervenidos mediante abordaje anterior y estabilización instrumentada combinada con la «cestilla de Moss» rellena de injerto óseo o cemento acrílico. La valoración clínica se realiza subjetivamente por la presencia de dolor y neurológicamente según los grados de Frankel pre y postoperatorios. Radiológicamente se valora la corrección de la cifosis/lordosis/acuñamiento según el método de Cobb. La utilización de la «cestilla de Moss» en fracturas patológicas vertebrales consigue una estabilidad completa sin dependencia de la fusión ósea.Pathological spinal fractures could induce neurological deficit, instability and deformity. Therefore, the objective of the treatment consists of re-establishing the most quickly possible the anatomy and normal function. In this sense, the utilization of a cylindrical mesh of titanium, like the Moss's mesh, provide an immediate stability permiting early loading. We report a retrospective study of 6 patients with pathological spinal fracture operated by anterior decompression and spine stabilization using the Moss's mesh padded of bone graft acrylic cement. Clinical assessment was made subjectively for the presence of pain and neurologic ally according to pre and postoperatively Frankel's grades. The correction of the kyphosis, lordosis and vertebral collapse was assessed according to the Cobb's method. The utilization of the Moss's mesh in pathological spinal fractures provides a complete stability without dependence of the status of bone fusion

Factores de riesgo asociados con recaídas de tuberculosis pulmonar en Cali, Colombia

Introduction: Relapses in tuberculosis occur due to endogenous reactivations or exogenous reinfections and represent up to 27% of tuberculosis cases. Its importance lies in the risk of the appearance of multidrug-resistant Mycobacterium tuberculosis strains.According to the reports published in 2011 by the Colombian Instituto Nacional de Salud, there were 572 relapse cases reported in the country, i.e., a rate of 4.9%. Data of the tuberculosis control program from the Secretaría de Salud Municipal in Cali reported a relapse rate of 6%, higher than the national one, during 2013 and 2014.Objective: To determine the risk factors associated with relapse in patients with pulmonary tuberculosis in Cali.Materials and methods: We conducted an observational, analytical, and case-control study (1:1), which comprised 81 cases of pulmonary tuberculosis relapses detected in 2013 and 2014. Additionally, we collected data on socio-demographic and clinical variables, as well as lifestyle and health services, to identify the potential risk factors associated with tuberculosis relapses. We used logistic regression to identify the risk factors.Results: After adjustments for some variables, our multivariate logistic regression analysis showed that the body mass index (BMI) (OR=0.90, 95%CI: 0.81–0.99) and population density (OR=0.99, 95%CI: 0.98–1.00) were inversely associated with tuberculosis relapses. Alcohol consumption increased the likelihood of tuberculosis relapse (OR=5.56, 95%CI: 1.18–26.26).Conclusions: Body mass index and population density were inversely associated with pulmonary tuberculosis relapses in Cali. On the contrary, alcohol consumption increased the likelihood of tuberculosis relapses.Introducción. Las recaídas en la tuberculosis se deben a reactivaciones endógenas o reinfecciones exógenas y alcanzan hasta el 27 % de los casos. Su importancia radica en el riesgo de aparición de cepas de Mycobacterium tuberculosis resistentes a múltiples fármacos. Según informes del Instituto Nacional de Salud de Colombia, en el 2011 se reportaron 572 recaídas, lo que representa un porcentaje del 4,9 %. Datos del programa de tuberculosis de la Secretaría de Salud Municipal de Cali registraron una tasa de recaídas del 6 % durante el 2013 y el 2014, lo que supera la tasa nacional.Objetivo. Determinar los factores asociados con la recaída en pacientes con tuberculosis pulmonar.Materiales y métodos. Se hizo un estudio observacional, analítico y de casos y controles en pacientes diagnosticados con tuberculosis pulmonar detectados entre el 2013 y el 2014.Se estudiaron las variables sociodemográficas, clínicas, de estilo de vida y las relacionadas con el programa y los factores de riesgo; se determinaron utilizando regresión logística.Resultados. Después de ajustar por otras variables, la regresión logística evidenció dos factores inversamente asociados con las recaídas: el índice de masa corporal (OR=0,90; IC95%: 0,81–0,99) y la densidad poblacional en las comunas (OR=0,99; IC95%:0,99–1,00. El consumo de alcohol aumentó la probabilidad de recaída (OR=5,56; IC95%: 1,18 – 26,26).Conclusiones. El índice de masa corporal y la densidad poblacional se asociaron inversamente con las recaídas por tuberculosis pulmonar en Cali. El consumo de alcohol estuvo directamente relacionado