3,046 research outputs found

    Wanted: specific nutritional biomarkers for food consumption for the study of its protective role in health.

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    Nutritional epidemiology focuses on an understanding of the relationship between diet and disease risk. The assessment of dietary and nutritional exposure is a complex methodological challenge. Traditionally, diet evaluations have been made by means of dietary data, such as 24-h recalls and food frequency or diet history questionnaires. However, all of these methods have some inherent weaknesses or limitations due to the limited accuracy in measuring the intake of food, nutrients or phytochemicals. Nowadays, nutritional biomarkers have become an attractive alternative approach. According to conventional definition..

    Resveratrol, a new biomarker of moderate wine intake?

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    In a recent study published in the British Journal of Nutrition, Spencer et al. (1) reviewed the strengths and the limitations of the biomarkers of dietary polyphenol intake, since nutritional biomarkers may be a better measure of dietary exposure than self-reported dietary data. These authors identified the criteria that must be considered in the development of such biomarkers as the following..

    Valorisation of macroalgae via the integration of hydrothermal carbonisation and anaerobic digestion

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    This study investigates the integration of hydrothermal carbonisation (HTC) with anaerobic digestion (AD) as a valorisation route for two macroalgae species; S. latissima (SL) and F. serratus (FS). HTC reactions were conducted at temperatures of 150°C, 200°C and 250°C, with resulting hydrochars, process waters and hydrothermal slurries assessed for biomethane potential yields. Un-treated SL generated similar biomethane levels compared to all SL slurries. Whereas all FS slurries improved biomethane yields compared to un-treated FS. Hydrochars represent a greater energy carrier if used as a solid fuel, rather than a feedstock for anaerobic digestion. Integrating HTC and AD, through hydrochar combustion and process water digestion has a greater energetic output than anaerobic digestion of the un-treated macroalgae. Treatment at 150°C, with separate utilisation of products, can improve the energetic output of S. latissima and F. serratus by 47 % and 172 % respectively, compared to digestion of the un-treated macroalgae

    Polymeric Squaraine Dyes as Electron Donors in Bulk Heterojunction Solar Cells

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    A polysquaraine low band gap polymer was synthesized by Yamamoto coupling of a monomeric dibromo indolenine squaraine dye. The resulting polymer has a weight average molar mass in the order of Mw ~30.000-50.000 and a polydispersity of ca. 1.7 as determined by gel-permeation chromatography (GPC). The electronic properties of monomer and polymer were investigated by cyclic voltammetry, absorption and emission spectroscopy. Owing to exciton coupling the absorption bands of the polymer are red-shifted and strongly broadened compared to the monomer squaraine dye. Bulk heterojunction solar cells were prepared from blends of the polysquaraine with the fullerene derivative [6,6]-phenyl C61-butyric acid methyl ester (PCBM) in different weight ratios (1:3 to 1:1). The power conversion efficiencies under simulated AM 1.5 conditions yielded 0.45 % for these non-optimized systems. The external quantum efficiency (EQE) shows that the photoresponse spans the range from 300 to 850 nm, which illustrates the promising properties of this novel organic semiconductor as a low band gap donor material in organic photovoltaics.Comment: 10 pages, 7 figure

    Precise absolute astrometry from the VLBA imaging and polarimetry survey at 5 GHz

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    We present in this paper accurate positions of 857 sources derived from the astrometric analysis of 16 eleven-hour experiments from the Very Long Baseline Array imaging and polarimetry survey at 5 GHz (VIPS). Among observed sources, positions of 430 objects were not determined before at a milliarcsecond level of accuracy. For 95% of the sources the uncertainty of their positions range from 0.3 to 0.9 mas, with the median value of 0.5 mas. This estimate of accuracy is substantiated by the comparison of positions of 386 sources that were previously observed in astrometric programs simultaneously at 2.3/8.6 GHz. Surprisingly, the ionosphere contribution to group delay was adequately modeled with the use of the total electron contents maps derived from GPS observations and only marginally affected estimates of source coordinates.Comment: Accepted for publication by the Astronomical Journal. 7 pages, 2 tables, 4 figures. Submission contains an ascii file with the catalogue. You can get the catalogue by downloading the source of this paper and extracting file table2.tx

    Resveratrol metabolite profiling in clinical nutrition research-from diet to uncovering disease risk biomarkers: epidemiological evidence

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    Resveratrol is a bioactive plant compound that has drawn scientific and media attention owing to its protective effects against a wide variety of illnesses, including cardiovascular diseases and cancer. In the last two decades, a plethora of preclinical studies have shown these beneficial effects, and some of them have been supported by clinical trials. However, there are few epidemiological studies assessing these relationships, showing mostly inconsistent results among them. This could be partially due to the difficulty of accurately estimating dietary resveratrol exposure. The development of Phenol-Explorer, a database containing resveratrol food-composition data, will facilitate the estimation of resveratrol intake. Moreover, the discovery and validation of a nutritional biomarker of this exposure, urinary resveratrol metabolite profile, will allow a more accurate assessment of dietary resveratrol exposure. Few epidemiological studies have assessed the potential health effects of resveratrol. Resveratrol was not associated with total mortality, cancer, or cardiovascular events, but it was associated with an improvement of serum glucose and triglyceride levels and a decrease in heart rate. Together, these findings suggest a potential cardioprotective effect of resveratrol in epidemiological studies, although the evidence is still scarce

    Radio Astrometry Of The Triple Systems Algol And UX Arietis

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    We have used multi-epoch long-baseline radio interferometry to determine the proper motion and orbital elements of Algol and UX Arietis, two radio-bright, close binary stellar systems with distant tertiary components. For Algol, we refine the proper motion and outer orbit solutions, confirming the recent result of Zavala et al. (2010) that the inner orbit is retrograde. The radio centroid closely tracks the motion of the KIV secondary. In addition, the radio morphology varies from double-lobed at low flux level to crescent-shaped during active periods. These results are most easily interpreted as synchrotron emission from a large, co-rotating meridional loop centered on the K-star. If this is correct, it provides a radio-optical frame tie candidate with an uncertainty {\pm}0.5 mas. For UX Arietis, we find a outer orbit solution that accounts for previous VLBI observations of an acceleration term in the proper motion fit. The outer orbit solution is also consistent with previously published radial velocity curves and speckle observations of a third body. The derived tertiary mass, 0.75 solar masses, is consistent with the K1 main-sequence star detected spectroscopically. The inner orbit solution favors radio emission from the active K0IV primary only. The radio morphology, consisting of a single, partially resolved emission region, may be associated with the persistent polar spot observed using Doppler imaging

    Colorimetric detection of caspase 3 activity and reactive oxygen derivatives: Potential early indicators of thermal stress in corals

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    © 2016 Mickael Ros et al. There is an urgent need to develop and implement rapid assessments of coral health to allow effective adaptive management in response to coastal development and global change. There is now increasing evidence that activation of caspase-dependent apoptosis plays a key role during coral bleaching and subsequent mortality. In this study, a "clinical" approach was used to assess coral health by measuring the activity of caspase 3 using a commercial kit. This method was first applied while inducing thermal bleaching in two coral species, Acropora millepora and Pocillopora damicornis. The latter species was then chosen to undergo further studies combining the detection of oxidative stress-related compounds (catalase activity and glutathione concentrations) as well as caspase activity during both stress and recovery phases. Zooxanthellae photosystem II (PSII) efficiency and cell density were measured in parallel to assess symbiont health. Our results demonstrate that the increased caspase 3 activity in the coral host could be detected before observing any significant decrease in the photochemical efficiency of PSII in the algal symbionts and/or their expulsion from the host. This study highlights the potential of host caspase 3 and reactive oxygen species scavenging activities as early indicators of stress in individual coral colonies

    Wholegrain Consumption and Risk Factors for Cardiorenal Metabolic Diseases in Chile: A Cross-Sectional Analysis of 2016-2017 Health National Survey

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    Abstract: Wholegrain (WG) consumption has been associated with reduced risk factors for cardiorenal metabolic diseases (CRMD). In Latin-America. WG intake is low and scarce studies on this subject have been found. We aimed to evaluate the association between WG consumption and risk factors for CRMD in the 2016-2017 Chilean-National Health Survey. This cross-sectional study included 3110 participants representative of a total population of 11,810,647 subjects > 18 y, not taking insulin and with complete data on CRMD risk factors. Outcomes were metabolic syndrome and its components, albuminuria, and impaired glomerular filtration rate (GFR). WG consumption was categorized as regular (≥every two days), sporadic (≥once a month), and non-consumers. Associations were analyzed by multivariable logistic regressions adjusted for confounders taking into account the complex sample design of the survey. Regular WG consumers showed a lower risk of high blood pressure (OR: 0.61, 95%CI: 0.41-0.91) compared to non-consumers in fully-adjusted models. Although inverse associations were noticed with other metabolic syndrome components and impaired GFR, none was statistically significant. The association between WG and BP remained robust in the sensitivity analysis. In conclusion regular WG consumption was associated with a 39% lower risk of high blood pressure in Chilean adults. Keywords: wholegrain; cardiovascular disease; metabolic syndrome; chronic kidney disease; Latin Americ
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