A multipolymer system for organocatalytic alcohol oxidation

A system involving two polymer-supported reagents for the selective and organocatalytic oxidation of alcohols to aldehydes or ketones has been developed in which both polymeric reagents can be recovered and reused. © The Royal Society of Chemistry 2005.postprin

Time variations in the deep underground muon flux measured by MACRO

More than 30 million of high-energy muons collected with the MACRO detector at the underground Gran Sasso Laboratory have been used to search for flux variations of different natures. Two kinds of studies were carried out: search for periodic variations and for the occurrence of clusters of events. Different analysis methods, including Lomb-Scargle spectral analysis and Scan Test statistics have been applied to the data.Comment: 6 pages, 4 EPS figures. Talk given at the 29th ICRC, Pune, India, 3-10 August 200

Time variations in the deep underground muon flux

More than 35 million high-energy muons collected with the MACRO detector at the underground Gran Sasso Laboratory have been used to search for flux variations of different nature. Two kinds of studies were carried out: a search for the occurrence of clusters of events and a search for periodic variations. Different analysis methods, including the Scan Statistics test and the Lomb-Scargle spectral analysis have been applied to the data.Comment: 7 pages, 5 figures, accepted by EP

Descriptive and Correlative Analysis of Anthropometric, Physiological and Nutritional Characteristics in University Students from Morelia, Mexico

Introduction: Non-communicable diseases (NCD) are the leading cause of mortality in the world. Among NCD varieties, obesity is a public health problem around the world, but it is especially important in poor or developing countries. The aim of this study is to explore the body composition, physical activity and food diversity in university students from Morelia, Mexico. Method: A cross sectional study was conducted with 422 students of university level. We used bioimpedance and anthropometry to determine the body composition of the students. The physical activity was analyzed by the International Physical Activity Questionnaire (IPAQ), while the food diversity was assessed by the guidelines for measuring household and individual dietary diversity of the Food and Agriculture Organization. Results: A matrix of 16 anthropometric variables was reduced to three principal components with a variance accumulate of 88.04% to women and 78.9% to men. We were able to separate groups of women based on anthropometric variables. In men, the percentage of muscle is the variable that most influences the separation of groups. The physical activity ranges from moderate to high; on average it was 5028.4 and 4449.4 MET-minutes/week for men and women respectively. A high food diversity and equitability of consumption was found, the socioeconomic level of the students does not allow inferring food insecurity. In men we found more associated variables than in women and we found no relationship with dietary diversity. We found statistically significant relationships between chronological age and metabolic age in both sexes, but we did not find a relationship between actual weight and ideal weight. Conclusion: In conclusion, we describe the body composition, anthropometry, physical activity and food diversity of university students.Introducción: Las enfermedades no transmisibles (ENT) son la principal causa de mortalidad en el mundo. Entre las variedades de ENT, la obesidad es un problema de salud pública en todo el mundo, pero es especialmente importante en los países pobres o en desarrollo. El objetivo de este estudio es explorar la composición corporal, la actividad física y la diversidad alimentaria en estudiantes universitarios de Morelia, México. Método: Se realizó un estudio transversal con 422 estudiantes de nivel universitario. Utilizamos bioimpedancia y antropometría para determinar la composición corporal de los estudiantes. La actividad física se analizó mediante el Cuestionario Internacional de Actividad Física (IPAQ), mientras que la diversidad alimentaria se evaluó mediante las directrices para medir la diversidad dietética familiar e individual de la Organización de las Naciones Unidas para la Agricultura y la Alimentación. Resultados: Se redujo una matriz de 16 variables antropométricas a tres componentes principales con un acumulado de varianza de 88.04% para mujeres y 78.9% para hombres. Pudimos separar grupos de mujeres en base a variables antropométricas. En los hombres, el porcentaje de músculo es la variable que más influye en la separación de grupos. La actividad física varía de moderada a alta; en promedio fue 5028.4 y 4449.4 MET-minutos/semana para hombres y mujeres respectivamente. Se encontró una alta diversidad alimentaria y equidad de consumo, el nivel socioeconómico de los estudiantes no permite inferir inseguridad alimentaria. En hombres encontramos más variables asociadas que en mujeres y no encontramos relación con la diversidad dietética. Encontramos relaciones estadísticamente significativas entre la edad cronológica y la edad metabólica en ambos sexos, pero no encontramos relación entre el peso real y el peso ideal. Conclusión: En conclusión, se describe la composición corporal, antropometría, actividad física y diversidad alimentaria de universitarios

Search for a Lorentz invariance violation contribution in atmospheric neutrino oscillations using MACRO data

Neutrino-induced upward-going muons in MACRO have been analysed in terms of relativity principles violating effects, keeping standard mass-induced atmospheric neutrino oscillations as the dominant source of nu_mu -> nu_tau transitions. The data disfavor these exotic possibilities even at a sub-dominant level, and stringent 90% C.L. limits are placed on the Lorentz invariance violation parameter |Delta v| < 6 * 10^(-24) at sin2theta_v = 0 and |Delta v| < 2.5--5 * 10^(-26) at sin2theta_v = +/-1. These limits can also be re-interpreted as upper bounds on the parameters describing violation of the Equivalence Principle.Comment: 8 pages, 2 figures, submitted to Physics Letters

An optically stimulated superconducting-like phase in K3C60 far above equilibrium Tc

The control of non-equilibrium phenomena in complex solids is an important research frontier, encompassing new effects like light induced superconductivity. Here, we show that coherent optical excitation of molecular vibrations in the organic conductor K3C60 can induce a non-equilibrium state with the optical properties of a superconductor. A transient gap in the real part of the optical conductivity and a low-frequency divergence of the imaginary part are measured for base temperatures far above equilibrium Tc=20 K. These findings underscore the role of coherent light fields in inducing emergent order.Comment: 40 pages, 23 figure

Annexin-A5 assembled into two-dimensional arrays promotes cell membrane repair

Eukaryotic cells possess a universal repair machinery that ensures rapid resealing of plasma membrane disruptions. Before resealing, the torn membrane is submitted to considerable tension, which functions to expand the disruption. Here we show that annexin-A5 (AnxA5), a protein that self-assembles into two-dimensional (2D) arrays on membranes upon Ca2+ activation, promotes membrane repair. Compared with wild-type mouse perivascular cells, AnxA5-null cells exhibit a severe membrane repair defect. Membrane repair in AnxA5-null cells is rescued by addition of AnxA5, which binds exclusively to disrupted membrane areas. In contrast, an AnxA5 mutant that lacks the ability of forming 2D arrays is unable to promote membrane repair. We propose that AnxA5 participates in a previously unrecognized step of the membrane repair process: triggered by the local influx of Ca2+, AnxA5 proteins bind to torn membrane edges and form a 2D array, which prevents wound expansion and promotes membrane resealing