Consumo de alimentos de alta densidad energética en los beneficiarios del programa Oportunidades. El caso del Área Metropolitana de Monterrey

El programa Oportunidades entrega a sus beneficiarios una transferencia monetaria para utilizarse en gastos que fomenten el capital humano como son la educación y alimentación. Los recursos no tienen ningún mecanismo de control al interior de los hogares, por lo que pueden ocuparse en alimentos que no contribuyan a una dieta sana. Por tal motivo, esta investigación se enfocó a analizar el consumo de tres alimentos de alto contenido energético como son las galletas, refrescos y frituras, entre los beneficiarios y no beneficiarios de dicho programa. Se encontró que no existen diferencias estadísticamente significativas en su consumo, pero sí que las ingestas son altas para ambos grupos

Inter and intra molecular dynamics in poly(trimethylene 2,5-furanoate) as revealed by infrared and Broadband Dielectric Spectroscopies

9 pags., 9 figs., 2 tabs.Infrared spectroscopy (IR) and Broadband Dielectric Spectroscopy (BDS) experiments have been performed in poly(trimethylene 2,5-furanoate)(PTF) and poly(trimethylene terephthalate)(PTT) below their glass transition temperatures. The BDS experiments reveal a richer inter-molecular dynamic for PTT as characterized by a multimodal β relaxation in contrast with the monomodal one exhibited by PTF. The evolution with temperature of comparable IR absorption bands is very similar for PTF and PTT and shows small shifts in wavenumbers towards lower values, with exception of the band related to the stretching mode of the carbonyl group. In addition, a significant difference appears in the shape of the bands associated with the –C[dbnd]O stretching. While for PTT the absorption feature is comprised of a single component, that for PTF exhibits several components suggesting the presence of hydrogen bonds. This effect may be responsible for the monomodal shape of the β relaxation of PTF since a higher degree of intramolecular coupling between the furan ring and the rest of the monomer is expected. Density Functional Theory (DFT) calculations support the experimental results revealing that as temperature increases an increment of the syn conformations of the 2,5-furandicarboxylic acid (FDCA) moiety is likely to occur in the amorphous state. The energy gain from more stable anti to less stable syn isomers can be compensated by the formation of hydrogen bonds between interchain FDCA moieties in syn conformations. This effect may cause additional hindrance to the intermolecular dynamics of the dielectric β relaxation. It is conceivable that the hindrance exhibited by PTF in both intra and inter-molecular dynamics may play a role in the reduction of gas diffusion and permeability of PTF in comparison with PTT.Grants PID2019-107514 GB-I00/AEI/10.13039/501100011033 and PID2019-106125 GB-I00/AEI/10.13039/501100011033 funded by MCIN/AEI/10.13039/501100011033 and by “ ERDF A way of making Europe”. GS acknowledges grant RYC2020-029810-I funded by MCIN/ AEI/10.13039/501100011033 and by “ ESF Investing in your future”. SP would like to thank for financial support from the National Science Centre within project SONATA no 2018/31/D/ST8/00792.

Is the sub-glass temperature relaxation of furan-based polymers related to their high gas barrier properties?

11th Conference on Broadband Dielectric Spectroscopy and its Applications (BDS2022), Donostia/San Sebastián, 04.Sep - 09.Sep 2022. -- Presentación con 25 diapositivasPoly(alkylene 2,5-furanoate)s, (PAF)s, are fully biobased homopolyesters based on 2,5-furandicarboxylic acid that have recently emerged as promising alternative to petroleum based poly(alkylene terephthalate)s. In addition to a lower production carbon footprint poly(alkylene 2,5-furanoate)s have received significant attention due to their outstanding gas barrier properties in comparison to traditional poly aromatic esters [1]. The influence of chain dynamics on barrier properties has also devoted some attention. Dielectric spectroscopy experiments performed in poly(trimethylene 2,5-furanoate) revealed that the subambient relaxation, below its glass transition temperature, exhibited an inhibition of the mode corresponding to the ester oxygen linked to the aliphatic subunit which efficiently relaxes in the poly(trimethylene terephthalate) counterpart [2]. Fourier Transform Infrared (FT-IR) spectroscopy can provide precise information of intra-molecular motions at the molecular level [3]. By evaluating the vibrational frequencies and the corresponding oscillator, strength from the IR spectra information about the intra-molecular dynamics can be available. In this study, we present a combined IR spectroscopy and BDS study focused on the sub-glass temperature molecular dynamics of poly(trimethylene 2,5-furanoate) in comparison to that of poly(trimethylene terephthalate) in order to shed light on the influence the dynamics on the barrier properties of Poly(alkylene 2,5-furanoate)s.The authors gratefully acknowledge the financial support of the Spanish Ministry of Science and Innovation (MICINN) through PID2019-107514GB-I00 / AEI / 10.13039/501100011033

Murine Models for the Study of Fetal Alcohol Spectrum Disorders: An Overview.

Prenatal alcohol exposure is associated to different physical, behavioral, cognitive, and neurological impairments collectively known as fetal alcohol spectrum disorder. The underlying mechanisms of ethanol toxicity are not completely understood. Experimental studies during human pregnancy to identify new diagnostic biomarkers are difficult to carry out beyond genetic or epigenetic analyses in biological matrices. Therefore, animal models are a useful tool to study the teratogenic effects of alcohol on the central nervous system and analyze the benefits of promising therapies. Animal models of alcohol spectrum disorder allow the analysis of key variables such as amount, timing and frequency of ethanol consumption to describe the harmful effects of prenatal alcohol exposure. In this review, we aim to synthetize neurodevelopmental disabilities in rodent fetal alcohol spectrum disorder phenotypes, considering facial dysmorphology and fetal growth restriction. We examine the different neurodevelopmental stages based on the most consistently implicated epigenetic mechanisms, cell types and molecular pathways, and assess the advantages and disadvantages of murine models in the study of fetal alcohol spectrum disorder, the different routes of alcohol administration, and alcohol consumption patterns applied to rodents. Finally, we analyze a wide range of phenotypic features to identify fetal alcohol spectrum disorder phenotypes in murine models, exploring facial dysmorphology, neurodevelopmental deficits, and growth restriction, as well as the methodologies used to evaluate behavioral and anatomical alterations produced by prenatal alcohol exposure in rodents

Aerosol properties derived from ground-based Fourier transform spectra within the COllaborative Carbon Column Observing Network

Fourier transform infrared (FTIR) spectroscopy is particularly relevant for climate studies due to its ability to provide information on both fine absorption structures (i.e. trace gases) and broadband continuum signatures (i.e. aerosols or water continuum) across the entire infrared (IR) domain. In this context, this study assesses the capability of the portable and compact EM27/SUN spectrometer, used within the research infrastructure COCCON (COllaborative Carbon Column Observing Network), to retrieve spectral aerosol properties from low-resolution FTIR solar absorption spectra (0.5 cm−1). The study focuses on the retrieval of aerosol optical depth (AOD) and its spectral dependence in the 873–2314 nm spectral range from COCCON measurements at the subtropical high-mountain Izaña Observatory (IZO, Tenerife, Spain), which were coincidentally carried out with standard sun photometry within the Aerosol Robotic Network (AERONET) in the 3-year period from December 2019 to September 2022. The co-located AERONET–COCCON database was used to cross-validate these two independent techniques in the common spectral range (870–1640 nm), demonstrating an excellent agreement at the near-coincident spectral bands (mean AOD differences limited to 0.005, standard deviations up to 0.021 and Pearson regression coefficients up to 0.97). This indicates that the low-resolution COCCON instruments are suitable for detecting the aerosol broadband signal contained in the IR spectra in addition to the retrieval of precise trace gas concentrations, provided a robust calibration procedure (Langley-based or absolute calibration procedures) is used to compensate for the optical degradation of the external system (∼ 0.72 % per month). The study also assesses the capability of the EM27/SUN to simultaneously infer aerosols and trace gases and relate their common emission sources in two case study events: a volcanic plume from the La Palma eruption in 2021 and a nearby forest fire in Tenerife in 2022. Overall, our results demonstrate the potential of the portable low-resolution COCCON instruments to enhance the multi-parameter capability of the FTIR technique for atmospheric monitoring.</p