Origin of the effective mobility in non-linear active micro-rheology

The distinction between the damping coefficient and the effective non-linear mobility of driven particles in active micro-rheology of supercooled liquids is explained in terms of individual and collective dynamics. The effective mobility arises as a collective effect which gives insight into the energy landscape of the system. On the other hand, the damping coefficient is a constant that modulates the effect of external forces over the thermal energy which particles have at their disposition to perform Brownian motion. For long times, these thermal fluctuations become characterized in terms of an effective temperature that is a consequence of the dynamic coupling between kinetic and configurational degrees of freedom induced by the presence of the strong external force. The interplay between collective mobility and effective temperature allows to formulate a generalized Stokes-Einstein relation that may be used to determine the collective diffusion coefficient. The explicit relations we deduce reproduce simulation data remarkably well

Derivados propenyl guaetol con potencial actividad biológica

El compuesto Propanil guaetol (1) también conocido como vinatrope, producto derivado por la ruta de síntesis vanitrópica de eugenol, este compuesto es conocido por ser aromatizante alimenticio (perfumersupplyhouse) . Por otra parte, una de las enfermedades que afecta a la industria salmonera de Chile es la saprolegniosis, patología que ha ocasionado una disminución de la productividad provocando graves pérdidas económicas a nivel nacional e internacional (. Zaror1, y otros, 2004). Como solución a esta patología se sintetizó una serie de 3 derivados de (1), mediante reacciones de química orgánica clásica, como acetilación y nitración. El compuesto de partida (1), los productos sintetizados 2-3 y el control comercial bronopol fueron evaluados frente a una cepa del patógeno Saprolegnia australis causante de la enfermedad mediante el método de microdilución. Los resultados obtenidos para la actividad in vitro frente al cultivo de Saprolegnia australis nos indican que el derivado 3 (acetato de propenil guaetol) presenta la mayor actividad con un porcentaje de inhibición de un 50%Fil: Morales, Ana. Universidad de Playa Ancha (Valparaíso, Chile).Fil: Flores, Susana. Universidad de Playa Ancha (Valparaíso, Chile).Fil: Madrid, Alejandro. Universidad de Playa Ancha (Valparaíso, Chile).Fil: Montenegro,Ivan. Universidad de Playa Ancha (Valparaíso, Chile)

Local thermodynamics and the generalized Gibbs-Duhem equation in systems with long-range interactions

The local thermodynamics of a system with long-range interactions in d dimensions is studied using the mean-field approximation. Long-range interactions are introduced through pair interaction potentials that decay as a power law in the interparticle distance. We compute the local entropy, Helmholtz free energy, and grand potential per particle in the microcanonical, canonical, and grand canonical ensembles, respectively. From the local entropy per particle we obtain the local equation of state of the system by using the condition of local thermodynamic equilibrium. This local equation of state has the form of the ideal gas equation of state, but with the density depending on the potential characterizing long-range interactions. By volume integration of the relation between the different thermodynamic potentials at the local level, we find the corresponding equation satisfied by the potentials at the global level. It is shown that the potential energy enters as a thermodynamic variable that modifies the global thermodynamic potentials. As a result, we find a generalized Gibbs-Duhem equation that relates the potential energy to the temperature, pressure, and chemical potential. For the marginal case where the power of the decaying interaction potential is equal to the dimension of the space, the usual Gibbs-Duhem equation is recovered. As examples of the application of this equation, we consider spatially uniform interaction potentials and the self-gravitating gas. We also point out a close relationship with the thermodynamics of small systems

Alpsnmr: an r package for signal processing of fully untargeted nmr-based metabolomics

Nuclear magnetic resonance (NMR)-based metabolomics is widely used to obtain metabolic fingerprints of biological systems. While targeted workflows require previous knowledge of metabolites, prior to statistical analysis, untargeted approaches remain a challenge. Computational tools dealing with fully untargeted NMR-based metabolomics are still scarce or not user-friendly. Therefore, we developed AlpsNMR (Automated spectraL Processing System for NMR), an R package that provides automated and efficient signal processing for untargeted NMR metabolomics. AlpsNMR includes spectra loading, metadata handling, automated outlier detection, spectra alignment and peak-picking, integration and normalization. The resulting output can be used for further statistical analysis. AlpsNMR proved effective in detecting metabolite changes in a test case. The tool allows less experienced users to easily implement this workflow from spectra to a ready-to-use dataset in their routines

Diferencias entre los modelos de riesgo Framingham y DAD en la evaluación del riesgo cardiovascular en pacientes con VIH bajo terapia antirretroviral: experiencia en una población del caribe colombiano

Objective: To assess the five- and ten-year cardiovascular disease risk in HIV-positive patients on antiretroviral therapy, using the Framingham risk score and the Data collection on adverse effects of anti-HIV drugs (D:A:D) study. Materials and methods: An observational prospective cross-sectional study. HIV-positive patients on antiretroviral treatment from a referral center for HIV patients were included in the study between January 1 and April 30, 2019. A five- and ten-year cardiovascular risk assessment was performed using the Framingham risk score and the D:A:D study. Additionally, both risk models were compared through statistical models. Results: The study population consisted of 159 patients with a mean age of 48.90 years ± 9.90. The mean cardiovascular risk according to the five-year Framingham risk score was 2.70 % ± 2.80, the ten-year Framingham risk score was 6.10 % ± 5.70, the five-year D:A:D study was 3.50 % ± 4.10, the ten-year D:A:D study was 6.90 % ± 7.70, and the ten-year Framingham risk score recalculated for Colombia (multiplied by 0.75) was 4.50 % ± 4.20. Using a logistic regression model, it was determined that the ten-year D:A:D study provided the greatest number of variables significantly related to a high cardiovascular risk. Conclusions: The study showed a significant difference between the risk models. Both the five- and ten-year D:A:D study provided a better cardiovascular disease risk estimation than the five- and ten-year Framingham model.Objetivo: Evaluar el riesgo de enfermedad cardiovascular a cinco y a diez años en pacientes con infección por VIH en terapia antirretroviral, por medio de las escalas Framingham y Data collection on Adverse Effects of Anti-HIV Drugs Study. Materiales y métodos: Estudio observacional de corte transversal y prospectivo. Se incluyeron pacientes con infección por el VIH en tratamiento antirretroviral de un centro de referencia para pacientes con VIH, entre el 1 de enero y el 30 de abril de 2019. Se realizó evaluación del riesgo cardiovascular a cinco y a diez años a través de los modelos de predicción de Framingham y la escala Data collection on Adverse Effects of Anti-HIV Drugs Study (DAD), y una comparación entre ellos a través de modelos estadísticos. Resultados: Se incluyeron 159 pacientes, con un promedio de edad de 48,90 años ± 9,90. La media de valoración del riesgo cardiovascular por escala de Framingham a 5 años fue de 2,70 % ± 2,80; Framingham a 10 años fue 6,10 % ± 5,70; DAD a 5 años, 3,50 % ± 4,10; DAD a 10 años, de 6,90 % ± 7,70; y el riesgo escala de Framingham a 10 años recalculado para Colombia (multiplicado por 0,75) fue de 4,50 ± 4,20. A través de un modelo de regresión logística, se determinó que la puntuación con mayor número de variables significativamente relacionadas con el resultado de riesgo cardiovascular alto es el modelo DAD a 10 años. Conclusiones: El estudio evidenció una diferencia significativa, con mayor riesgo estimado de enfermedad cardiovascular al utilizar el modelo DAD en comparación con el Framingham, tanto para la estimación a cinco años como a diez

Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London