Limit cycles from a monodromic infinity in planar piecewise linear systems

Planar piecewise linear systems with two linearity zones separated by a straight line and with a periodic orbit at infinity are considered. By using some changes of variables and parameters, a reduced canonical form with five parameters is obtained. Instead of the usual Bendixson transformation to work near infinity, a more direct approach is introduced by taking suitable coordinates for the crossing points of the possible periodic orbits with the separation straight line. The required computations to characterize the stability and bifurcations of the periodic orbit at infinity are much easier. It is shown that the Hopf bifurcation at infinity can have degeneracies of co-dimension three and, in particular, up to three limit cycles can bifurcate from the periodic orbit at infinity. This provides a new mechanism to explain the claimed maximum number of limit cycles in this family of systems. The centers at infinity classification together with the limit cycles bifurcating from them are also analyzed.Comment: 24 pages, 5 figure

Estructura sanitaria de atención al tabaquismo

El presente artículo trata de analizar la necesidad de generar una estructura sanitaria de atención al tabaquismo en los distintos departamentos de salud, dependientes de la red pública sanitaria. Esta estructura cobra fuerza y llega a un mayor número de sujetos si se asienta sobre la Atención Primaria de salud, articulándose alrededor de las consultas específicas de tabaquismo en los distintos centros de Salud. Estas consultas deben contar como mínimo con un médico y una enfermera que se dediquen especialmente a atender la consulta al menos 4 horas a la semana. Aun siendo la Atención Primaria la principal puerta de entrada de los pacientes, no podemos descartar el papel de otras unidades o servicios como, medicina Preventiva, los servicios de Neumología o las Unidades de Conductas Adictivas, que también deben hacer un papel importante a la hora de su interrelación. Con todo esto hay que establecer una correcta coordinación entre los distintos servicios, consultas y unidades, sumando a ellas los recursos de Salud Pública e incluso el apoyo que se pueda ofrecer desde distintos ayuntamientos y otras administraciones no sanitarias. Al contar con una estructura definida y una organización coordinada se puede llegar al máximo número de pacientes, además de realizar otras tareas como la prevención o incluso la investigación en este campo, por parte de personas que conozcan toda la problemática de los fumadores. A pesar de los documentos previos, llega la hora de que los distintos gobiernos tanto a nivel autonómico como estatal, consensúen y establezcan un modelo de Atención sanitaria al tabaquismo para todo el Estado español. En este trabajo, aparte de presentar nuestro proyecto, ofrecemos los resultados preliminares que nos indica que nuestra experiencia es efectiva y eficiente en nuestro Departamento de Salud cuando se compara con otros trabajos. Esperamos que con el seguimiento aportemos datos más concluyentes

Time to disease diagnosis in patients with diabetes and arterial hypertension with symptoms of depression in a sample of Peruvian residents.

Introducción: La prevalencia de HTA se encuentra entre 11,9 % y 49 %, la prevalencia de DM2 es de 10,5 %. La prevalencia de trastornos depresivos en diabéticos va en el rango de 10 % a 15 %. Objetivo: determinar la asociación entre el tiempo de enfermedad de los pacientes con HTA y DM2 con los síntomas de depresión. Metodología: Estudio analítico transversal. La base secundaria analizada fue la Encuesta Demográfica y de Salud del Perú (ENDES) de los años 2019, 2020 y 2021. Se utilizó el Cuestionario de Salud del Paciente-9 (PHQ-9). Se utilizó la prueba del chi cuadrado para cada posible factor asociado a la depresión y las asociaciones de interés se evaluaron con una distribución de Poisson. Resultados: El 21,59 % tenían síntomas de depresión al momento del estudio. El 51,40 % eran del sexo femenino. El 16,58 % presentaba mayor a 60 años. La HTA estuvo presente en el 5.9%, mientras que la DM2 en el 2,09 %. En el análisis bivariado, todas las variables se asociaron con la presencia de síntomas depresivos, excepto la variable que fuma a diario (p=0.275). Discusión: Los resultados señalan una asociación entre el tiempo de enfermedad desde el diagnóstico de HTA y DM2 con los síntomas depresivos. En el caso de ambas patologías el tener menos de un año de diagnóstico aumentaban en 51 % y 44 % respectivamente la probabilidad de presentar síntomas depresivos.Introduction: The prevalence of AHT is between 11.9 % and 49 %, and that of DM2 is 10.5 %. The prevalence of depressive disorders in patients with diabetes ranges from 10 to 15%. Objective: To determine the association between the time of illness in patients with hypertension and DM2 with depressive symptoms. Methodology: This was a cross-sectional analytical study. The secondary base analyzed was the Demographic and Health Survey of Peru (ENDES) for 2019, 2020, and 2021. The Patient Health Questionnaire-9 (PHQ-9) was used. The chi-square test was used for each possible factor associated with depression, and the associations of interest were evaluated using Poisson distribution. Results: At the time of the study, 21.59% of patients had symptoms of depression. Of these patients, 51.40 % were female. A total of 16.58 % of the participants were older than 60 years of age. Hypertension was present in 5.9% of the patients, while DM2 was present in 2.09%. In the bivariate analysis, all variables were associated with the presence of depressive symptoms, except for daily smoking (p=0.275). Discussion: The results showed an association between the time of illness since the diagnosis of HT and DM2 and depressive symptoms. In the case of both pathologies, having less than one year since diagnosis increased the probability of depressive symptoms by 51% and 44%, respectively

INTERVENCIÓN DEL LABORATORIO CLÍNICO EN LA DETECCIÓN E IMPORTANCIA DE LA HIPERLIPIDEMIA EN PERSONAS DE 30 A 50 AÑOS QUE SE ATIENDEN EN EL HOSPITAL DEL IESS DE LA CIUDAD DE JIPIJAPA DURANTE EL AÑO 2006.

PARA REALIZAR LA PRESENTE INVESTIGACIÓN SE TOMÓ COMO REFERENCIA A UN GRUPO DE 60 PERSONAS EN EDADES COMPRENDIDAS DE 30-60 AÑOS QUE SE ATIENDEN EN EL HOSPITAL DEL IESS DE LA CIUDAD DE JIPIJAPA ENTRE LOS MESES DE JULIO A SEPTIEMBRE DEL 2006, A LOS CUALES SE LES REALIZARON EXÁMENES MEDIANTE TÉCNICAS DE LABORATORIO CLÍNICO PARA DETERMINAR LOS VALORES DE LAS DIFERENTES ENZIMAS CON RESULTADOS DE ALTA CONFIABILIDAD.LA PRESENTE INVESTIGACIÓN TIENE COMO OBJETIVO GENERAL: DETERMINAR LA IMPORTANCIA DE HIPERLIPIDEMIAS EN PERSONAS CON EDADES ENTRE 30 A 50 AÑOS QUE SE ATIENDEN EN EL HOSPITAL DEL IESS DE LA CIUDAD DE JIPIJAPA; APOYADOS EN TÉCNICAS DE LABORATORIO CLÍNICO PARA QUE MEDIANTE LA EJECUCIÓN DE UN PROGRAMA DE EDUCACIÓN PREVENTIVA DIRIGIDA A ESTA POBLACIÓN, SE LOGRE LA DETECCIÓN OPORTUNA Y LA PREVENCIÓN DE ESTE TRASTORNO

Metabolically Obese Normal-Weight Phenotype as a Risk Factor for High Blood Pressure: A Five-Year Cohort

"Background: The metabolically obese normal-weight (MONW) phenotype has been considered a risk factor for different chronic diseases, but its role in high blood pressure (HBP) is still unclear. The aim of the study is to determine if the MONW phenotype constitutes a risk factor for hypertension in Peruvian adults belonging to a 5-year cohort. Methods: This is a retrospective cohort study. A secondary analysis from the database of the PERU MIGRANT study was carried out from the MONW and non-MONW cohorts; after a 5-year follow-up, the appearance of HBP was evaluated in the subjects of both cohorts. To assess the strength and magnitude of the association, a Poisson regression model (crude and adjusted) with robust variance was used. The measure of association was the relative risk (RR). Results: The incidence of HBP was 11.30%. In the multivariable analysis, subjects with the MONW phenotype had a 2.879-fold risk of presenting HBP in 5 years compared with those who were not MONW at the beginning of the study; this was adjusted for categorized age, sex, group, and state of smoker and alcohol drinker (RR: 2.055; 95% confidence interval (CI): 1.118 - 3.777; P = 0.020). Conclusions: The presence of the MONW phenotype doubled the incidence of HBP, even after adjusting for other covariates. However, studies in this field should continue. If these findings are confirmed, it should be considered that presenting an adequate weight for height should not be interpreted as a condition free of metabolic alterations, so screening for hypertension should be carried out regardless of w

Identification of Leishmania infantum Epidemiology, Drug Resistance and Pathogenicity Biomarkers with Nanopore Sequencing

The emergence of drug-resistant strains of the parasite Leishmania infantum infecting dogs and humans represents an increasing threat. L. infantum genomes are complex and unstable with extensive structural variations, ranging from aneuploidies to multiple copy number variations (CNVs). These CNVs have recently been validated as biomarkers of Leishmania concerning virulence, tissue tropism, and drug resistance. As a proof-of-concept to develop a novel diagnosis platform (LeishGenApp), four L. infantum samples from humans and dogs were nanopore sequenced. Samples were epidemiologically typed within the Mediterranean L. infantum group, identifying members of the JCP5 and non-JCP5 subgroups, using the conserved region (CR) of the maxicircle kinetoplast. Aneuploidies were frequent and heterogenous between samples, yet only chromosome 31 tetrasomy was common between all the samples. A high frequency of aneuploidies was observed for samples with long passage history (MHOM/TN/80/IPT-1), whereas fewer were detected for samples maintained in vivo (MCRI/ES/2006/CATB033). Twenty-two genes were studied to generate a genetic pharmacoresistance profile against miltefosine, allopurinol, trivalent antimonials, amphotericin, and paromomycin. MHOM/TN/80/IPT-1 and MCRI/ES/2006/CATB033 displayed a genetic profile with potential resistance against miltefosine and allopurinol. Meanwhile, MHOM/ES/2016/CATB101 and LCAN/ES/2020/CATB102 were identified as potentially resistant against paromomycin. All four samples displayed a genetic profile for resistance against trivalent antimonials. Overall, this proof-of-concept revealed the potential of nanopore sequencing and LeishGenApp for the determination of epidemiological, drug resistance, and pathogenicity biomarkers in L. infantum

The Fruit Intake–Adiposity Paradox: Findings from a Peruvian Cross-Sectional Study

"Due to the increase in obesity worldwide, international organizations have promoted the adoption of a healthy lifestyle, as part of which fruit consumption stands out. However, there are controversies regarding the role of fruit consumption in mitigating this disease. The objective of the present study was to analyze the association between fruit intake and body mass index (BMI) and waist circumference (WC) in a representative sample of Peruvians. This is an analytical cross-sectional study. Secondary data analysis was conducted using information from the Demographic and Health Survey of Peru (2019–2021). The outcome variables were BMI and WC. The exploratory variable was fruit intake, which was expressed in three different presentations: portion, salad, and juice. A generalized linear model of the Gaussian family and identity link function were performed to obtain the crude and adjusted beta coefficients. A total of 98,741 subjects were included in the study. Females comprised 54.4% of the sample. In the multivariate analysis, for each serving of fruit intake, the BMI decreased by 0.15 kg/m2 (β = −0.15; 95% CI −0.24 to −0.07), while the WC was reduced by 0.40 cm (β = −0.40; 95% CI −0.52 to −0.27). A negative association between fruit salad intake and WC was found (β = −0.28; 95% CI −0.56 to −0.01). No statistically significant association between fruit salad intake and BMI was found. In the case of fruit juice, for each glass of juice consumed, the BMI increased by 0.27 kg/m2 (β = 0.27; 95% CI 0.14 to 0.40), while the WC increased by 0.40 cm (β = 0.40; 95% CI 0.20 to 0.60). Fruit intake per serving is negatively related to general body adiposity and central fat distribution, while fruit salad intake is negatively related to central distribution adiposity. However, the consumption of fruit in the form of juices is positively associated with a significant increase in BMI and WC.

The Fruit Intake–Adiposity Paradox: Findings from a Peruvian Cross-Sectional Study

"Due to the increase in obesity worldwide, international organizations have promoted the adoption of a healthy lifestyle, as part of which fruit consumption stands out. However, there are controversies regarding the role of fruit consumption in mitigating this disease. The objective of the present study was to analyze the association between fruit intake and body mass index (BMI) and waist circumference (WC) in a representative sample of Peruvians. This is an analytical cross-sectional study. Secondary data analysis was conducted using information from the Demographic and Health Survey of Peru (2019–2021). The outcome variables were BMI and WC. The exploratory variable was fruit intake, which was expressed in three different presentations: portion, salad, and juice. A generalized linear model of the Gaussian family and identity link function were performed to obtain the crude and adjusted beta coefficients. A total of 98,741 subjects were included in the study. Females comprised 54.4% of the sample. In the multivariate analysis, for each serving of fruit intake, the BMI decreased by 0.15 kg/m2 (β = −0.15; 95% CI −0.24 to −0.07), while the WC was reduced by 0.40 cm (β = −0.40; 95% CI −0.52 to −0.27). A negative association between fruit salad intake and WC was found (β = −0.28; 95% CI −0.56 to −0.01). No statistically significant association between fruit salad intake and BMI was found. In the case of fruit juice, for each glass of juice consumed, the BMI increased by 0.27 kg/m2 (β = 0.27; 95% CI 0.14 to 0.40), while the WC increased by 0.40 cm (β = 0.40; 95% CI 0.20 to 0.60). Fruit intake per serving is negatively related to general body adiposity and central fat distribution, while fruit salad intake is negatively related to central distribution adiposity. However, the consumption of fruit in the form of juices is positively associated with a significant increase in BMI and WC.