A TPC (time projection chamber) for axion searches in the CAST experiment at CERN

Hypothetical axion-like particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field they would be transformed into X-rays with energies of a few keV. The CAST experiment at CERN is using a decommissioned LHC magnet as an axion helioscope in order to search for these axion-like particles. The TPC in one of its three X-ray detectors, which looks for the "sunset" axions. The analysis of the 2003 data taken with this detector has shown no signal above the background, thus implying an upper limit to the axion-photon coupling of gagg < 1.55*10^-10 GeV^-1 at 95 % CL for ma < 0.02 eV. The stable operation of the experiment and the TPC during 2004 data taking allowed us to lower this value down to gagg < 1.29*10^-10 GeV^-1 at 95 % CL for ma < 0.02 eV. This work describes the analysis procedure for the data collected these two years

Uncovering a Role for SK2 in Angelman Syndrome

Angelman syndrome is a severe neurodevelopmental disorder caused by mutations in UBE3A. Sun et al. (2015) report SK2 as a UBE3A substrate and provide insight into the molecular mechanisms that might underlie impaired neuronal function in individuals affected by Angelman syndrome

Análisis y propuestas de acción sobre legislación referida al consumo eficiente del agua

El agua es un recurso limitado e indispensable para la supervivencia humana. Una política sustentable, garantiza la preservación de la misma en las fuentes evitando su agotamiento, reduce costos y contaminación, ya que produce una disminución en su consumo y la cantidad de fluentes a tratar. Toda estrategia de ahorro debe abarcar: una legislación acorde a nivel, provincial y nacional, métodos y técnicas de eficiencia, la tecnología disponible, recomendaciones y acciones. Nuestro país se ha caracterizado por carecer de una legislación y políticas referidas al consumo eficiente del agua. En este trabajo se plantea un análisis de la legislación referida al tema. Se comparó la legislación existente en Argentina y en diversos centros urbanos a nivel internacional, con el objetivo de poder determinar las carencias existentes en nuestro medio y definir así conclusiones que lleven a posibles líneas de acción al respecto.Fil: Rodríguez, Viviana L. Universidad Nacional de Cuyo. Facultad de Filosofía y LetrasFil: Lizarraga, Susana B. Universidad Nacional de Cuyo. Facultad de Filosofía y LetrasFil: Araujo, Héctor. Universidad Nacional de Cuyo. Facultad de Filosofía y Letra

Human biomonitoring of mycotoxins in blood, plasma and serum in recent years: a review

This manuscript reviews the state-of-the-art regarding human biological monitoring (HBM) of mycotoxins in plasma, serum and blood samples. After a comprehensive and systematic literature review, with a focus on the last five years, several aspects were analyzed and summarized: (a) the biomarkers analyzed and their encountered levels, (b) the analytical methodologies developed and (c) the relationship between biomarker levels and some illnesses. In the literature reviewed, aflatoxin B1-lysine (AFB1-lys) and ochratoxin A (OTA) in plasma and serum were the most widely studied mycotoxin biomarkers for HBM. Regarding analytical methodologies, a clear increase in the development of methods for the simultaneous determination of multiple mycotoxins has been observed. For this purpose, the use of liquid chromatography (LC) methodologies, especially when coupled with tandem mass spectrometry (MS/MS) or high resolution mass spectrometry (HRMS) has grown. A high percentage of the samples analyzed for OTA or aflatoxin B1 (mostly as AFB1-lys) in the reviewed papers were positive, demonstrating human exposure to mycotoxins. This review confirms the importance of mycotoxin human biomonitoring and highlights the important challenges that should be faced, such as the inclusion of other mycotoxins in HBM programs, the need to increase knowledge of mycotoxin metabolism and toxicokinetics, and the need for reference materials and new methodologies for treating samples. In addition, guidelines are required for analytical method validation, as well as equations to establish the relationship between human fluid levels and mycotoxin intake

Modulation of neuronal cell affinity of composites scaffolds based on polyhydroxyalkanoates and bioactive glasses

Biocompatibility and neuron regenerating properties of various bioactive glass (BG)/Polyhydroxyalkanoate (PHA) blend composites were assessed in order to study their suitability for peripheral nerve tissue applications, specifically as lumen structures for nerve guidance conduits (NGCs). BG/PHA blend composites were fabricated using Bioactive glass® 45S5 (BG1) and BG 1393 (BG2) with the 25:35 poly(3-hydroxyoctanoate/poly3-hydroxybutyrate), 25:75 P(3HO)/P(3HB) blend (PHA blend). Various concentrations of each BG (0.5, 1.0 and 2.5 wt%) were used to determine the effect of BG on neuronal growth and differentiation, in single culture using NG108-15 neuronal cells and in a co-culture along with RN22 Schwann cells. NG108-15 cells exhibited good growth and differentiation on all the PHA blend composites showing that both BGs have good biocompatibility at 0.5, 1.0 and 2.5 wt% within the PHA blend. The Young's modulus values displayed by all the PHA blend/BG composites ranged from 385.6 MPa to 1792.6 MPa, which are able to provide the required support and protective effect for regeneration of peripheral nerves. More specifically, the tensile strength obtained in the PHA blend/BG1 (1.0 wt%) (10.0 ± 0.6 MPa) was found to be similar to that of rabbit peroneal nerve. This composite also exhibited the best biological performance in supporting growth and neuronal differentiation among all the substrates. The neurite extension on this composite was found to be remarkable with the neurites forming a complex connection network

Development and validation of a methodology based on Captiva EMR-lipid clean-up and LC-MS/MS analysis for the simultaneous determination of mycotoxins in human plasma

We report the methodology for the quantification of 19 mycotoxins in human plasma using high performance liquid chromatography-mass spectrometry (triple quadrupole). The studied mycotoxins were: deepoxy-deoxynivalenol, aflatoxins (B1, B2, G1, G2 and M1), T-2 and HT-2, ochratoxins A and B, zearalenone, sterigmatocystin, nivalenol, deoxynivalenol, 3-acetyldeoxynivalenol, 15-acetyldeoxynivalenol, neosolaniol, diacetoxyscirpenol and fusarenon-X. Sample deproteinization and cleanup were performed in one step using Captiva EMR-lipid (3 mL) cartridges and acetonitrile (with 1% formic acid). The extraction step was simple and fast. Validation was based on the evaluation of limits of detection (LOD) and quantification, linearity, precision, recovery, matrix effect, and stability. LOD values ranged from 0.04 ng/mL for aflatoxin B1 to 2.7 ng/mL for HT-2, except for nivalenol, which was 9.1 ng/mL. Recovery was obtained in intermediate precision conditions and at three concentration levels. Mean values ranged from 68.8% for sterigmatocystin to 97.6% for diacetoxyscirpenol (RDS ≤ 15% for all the mycotoxins). Matrix effects (assessed at three concentration levels and in intermediate conditions) were not significant for most of the mycotoxins and were between 75.4% for sterigmatocystin and 109.3% for ochratoxin B (RDS ≤ 15% for all the mycotoxins). This methodology will be useful in human biomonitoring studies of mycotoxins for its reliability

Forward-backward asymmetry in top quark-antiquark production

This is the publisher's version, also available electronically from http://journals.aps.org/prd/abstract/10.1103/PhysRevD.84.112005

Catch-up growth in juvenile rats, fat expansion, and dysregulation of visceral adipose tissue

BACKGROUND: Accelerated catch-up growth following intrauterine restriction increases the risk of developing visceral adiposity and metabolic abnormalities. However, the underlying molecular mechanisms of such metabolic programming are still poorly understood. METHODS: A Wistar rat model of catch-up growth following intrauterine restriction was used. A gene expression array was performed in the retroperitoneal adipose tissue sampled at postnatal day (PD) 42. RESULTS: Five hundred and forty-six differentially expressed genes (DEGs) were identified (adjusted p value < 0.05). Gene ontology enrichment analysis identified pathways related to immune and lipid metabolic processes, brown fat cell differentiation, and regulation of PI3K. Ccl21, Npr3, Serpina3n, Pnpla3, Slc2a4, and Serpina12 were validated to be upregulated in catch-up pups (all p < 0.01) and related to several fat expansion and metabolic parameters, including body weight at PD42, postnatal body weight gain, white and brown adipose tissue mass, plasma triglycerides, and insulin resistance index (all p < 0.05). CONCLUSIONS: Genes related to immune and metabolic processes were upregulated in retroperitoneal adipose tissue following catch-up growth in juvenile rats and were found to be associated with fat expansion and metabolic parameters. Our results provide evidence for several dysregulated genes in white adipose tissue that could help develop novel strategies to prevent the metabolic abnormalities associated with catch-up growth

Risk scoring models for trade credit in small and medium enterprises

Trade credit refers to providing goods and services on a deferred payment basis. Commercial credit management is a matter of great importance for most small and medium enterprises (SMEs), since it represents a significant portion of their assets. Commercial lending involves assuming some credit risk due to exposure to default. Thus, the management of trade credit and payment delays is strongly related to the liquidation and bankruptcy of enterprises. In this paper we study the relationship between trade credit management and the level of risk in SMEs. Despite its relevance for most SMEs, this problem has not been sufficiently analyzed in the existing literature. After a brief review of existing literature, we use a large database of enterprises to analyze data and propose a multivariate decision-tree model which aims at explaining the level of risk as a function of several variables, both of financial and non-financial nature. Decision trees replace the equation in parametric regression models with a set of rules. This feature is an important aid for the decision process of risk experts, as it allows them to reduce time and then the economic cost of their decisions