855 research outputs found

    Benzyltrimethylammonium dihydrogen orthophosphate monohydrate

    Get PDF
    The title compound, C 10 H 16 N + H 2 PO 4 H 2 O, crystallizes in the centrosymmetric space group P 2 1 / c with two independent molecules in the asymmetric unit. Therefore, nonlinear optical properties are absent. The crystal packing is governed by hydrogen bonds, so that the phosphate anions are linked head- to-tail, forming chains running parallel to the a direction. These chains in turn are interconnected by hydrogen bonds to water molecules, forming hydrogen-bonded molecular layers stacked parallel to the ab planeCICYT BFM2002-03327FEDE

    Spanish children's diet: compliance with nutrient and food intake guidelines

    Get PDF
    OBJECTIVE: To compare the diet of Spanish children against the nutrient and food intake guidelines. To calculate an index of overall diet quality and check its validity against nutrient intake. DESIGN AND SETTING: Cross-sectional study in four cities in Spain, where information on food and nutrient intake was obtained from schoolchildren through a food frequency questionnaire. PARTICIPANTS: The sample included 1112 children (overall response rate of 85%) attending public and private schools and aged 6-7 y. Children were selected through random cluster sampling in schools, and stratified by sex and socioeconomic level. MAIN OUTCOME MEASURES: Mean nutrient intake, number of food servings, and the percentage of children who meet recommended nutrient and food-serving intake levels. The overall dietary quality was assessed using the Healthy Eating Index (HEI). RESULTS: Mean micronutrient intake exceeded 100% of the recommended dietary allowances, except for vitamin B6, which registered a mean intake of 77.1%. For almost all children, intake of saturated fat was above, and that of carbohydrate below, the recommended level, in contrast to the relatively high compliance with the recommendations for poly- and monounsaturated fatty acid, salt and fiber intake (69.7, 43.7, 40.7, and 30.1%, respectively). Consumption of food servings for each of the five American pyramid food groups came close to or exceeded USDA guidelines, with the exception of cereals, with 5.4 servings per day. The mean score obtained in the HEI was 64.6. Children who complied with all the food guide pyramid recommendations registered a higher dietary variety and a healthier nutritional profile. CONCLUSIONS: Children aged 6-7 y show scant compliance with the macronutrient goals for healthy eating. Micronutrient intake is adequate in general, yet there are small groups of children with risk of deficient intake of vitamins B6 and D. While Spanish children's eating habits are reasonably in line with American food guide pyramid guidelines, consumptions of cereals and fruit should be improved.This study was partly funded by grants from the Inter-national Olive Oil Board (Consejo Oleı ́cola Internacional),Comunidad de Madrid, Fundacio ́n Pedro Barrie ́de laMaza, and Fundacio ́n Eugenio Rodrı ́guez Pascua

    Food sources of nutrients in the diet of Spanish children: the Four Provinces Study

    Get PDF
    The aim of the present study was to assess the principal food sources of energy and nutrients among Spanish children. We used a cross-sectional study design, based on results obtained from a food-frequency questionnaire. The sample included 1112 children, aged 6-7 years, from Cadiz, Madrid, Orense and Murcia, Spain. Children were selected through random cluster-sampling in schools. We analysed the percentage contributed by each food item to total energy and nutrient intake. The most important food sources were: white bread in the case of carbohydrate (13.4 %); olive oil in the case of total lipids (18.3 %) and monounsaturated fatty acids (29.2 %); whole milk in the case of protein (10.2 %) and saturated fatty acids (14.9 %); chips (French fried potatoes) in the case of polyunsaturated fatty acids (30.4 %). The greatest proportion of Na, consumed in excess, came from salt added to meals. Ham ranked second as a source of saturated fats. Fruits and green leafy vegetables proved to have great relevance as sources of fibre and vitamins, though with regard to the latter, it was observed that fortified foods (breakfast cereals, dairy products, fruit juices, etc.) had come to play a relevant role in many cases. In conclusion, the nutritional profile of Spanish school-aged children aged 6-7 years could be improved by nutritional policies targeted at limiting their consumption of ham (cured or cooked) and of salt added to meals, replacing whole milk with semi-skimmed milk, encouraging the consumption of products rich in complex carbohydrates already present in children's diets (bread, pasta, rice) and promoting less fatty ways of cooking food.This study was partly funded by grants from the Inter-national Olive Oil Board (Consejo Oleı ́cola Internacional),Madrid Regional Authority (Comunidad de Madrid), PedroBarrie ́de la Maza Foundation and Eugenio Rodrı ́guezPascual FoundationS

    Greater dietary variety is associated with better biochemical nutritional status in Spanish children: the Four Provinces Study

    Get PDF
    BACKGROUND AND AIM: Although dietary variety has been associated with a better nutritional profile, its possible role in obesity raises doubts about its overall health benefits. In this study, we examined the association between dietary variety and anthropometric variables, food intake and various food intake biomarkers in Spanish children. METHODS AND RESULTS: This was a cross-sectional study of 1112 children aged 6-7 years from Cadiz, Murcia, Orense and Madrid, who were selected by means of the random cluster-sampling of schools. Information concerning food and nutrient intake was obtained using a food frequency questionnaire, and a dietary variety index (DVI) was calculated on the basis of the number of different foods consumed more than once a month. The anthropometric variables (weight and height), and plasma lipid and vitamin levels were determined using standardised methods. Our results show that the body mass index (BMI) did not vary substantially as a function of DVI: it was 16.9 in the lowest DVI tertile and 17.2 in the highest (p=0.20). Unlike BMI, the DVI positively correlated (p<0.05) with the plasma levels of alpha and beta-carotene, lycopene, retinol, alpha-tocopherol and vitamin E, with energy intake, and with most of the foods, particularly vegetables, fruit and sausages (respective correlation coefficients of 0.43, 0.26 and 0.23). CONCLUSIONS: Dietary variety is associated with a better food and nutritional profile in Spanish children. Nevertheless, the presence of a positive association between the DVI and energy intake, and the consumption of sausages and pre-cooked products calls for the recommendation of a varied diet of healthy foods, such as cereals (especially whole grains), fruits and vegetables

    Observation of Pulsed Gamma-rays Above 25 GeV from the Crab Pulsar with MAGIC

    Get PDF
    One fundamental question about pulsars concerns the mechanism of their pulsed electromagnetic emission. Measuring the high-end region of a pulsar's spectrum would shed light on this question. By developing a new electronic trigger, we lowered the threshold of the Major Atmospheric gamma-ray Imaging Cherenkov (MAGIC) telescope to 25 GeV. In this configuration, we detected pulsed gamma-rays from the Crab pulsar that were greater than 25 GeV, revealing a relatively high cutoff energy in the phase-averaged spectrum. This indicates that the emission occurs far out in the magnetosphere, hence excluding the polar-cap scenario as a possible explanation of our measurement. The high cutoff energy also challenges the slot-gap scenario.Comment: Slight modification of the analysis: Fitting a more general function to the combined data set of COMPTEL, EGRET and MAGIC. Final result and conclusion is unchange

    First bounds on the high-energy emission from isolated Wolf-Rayet binary systems

    Get PDF
    High-energy gamma-ray emission is theoretically expected to arise in tight binary star systems (with high mass loss and high velocity winds), although the evidence of this relationship has proven to be elusive so far. Here we present the first bounds on this putative emission from isolated Wolf-Rayet (WR) star binaries, WR 147 and WR 146, obtained from observations with the MAGIC telescope.Comment: (Authors are the MAGIC Collaboration.) Manuscript in press at The Astrophysical Journal Letter

    Upper limit for gamma-ray emission above 140 GeV from the dwarf spheroidal galaxy Draco

    Get PDF
    The nearby dwarf spheroidal galaxy Draco with its high mass to light ratio is one of the most auspicious targets for indirect dark matter searches. Annihilation of hypothetical DM particles can result in high-energy gamma-rays, e.g. from neutralino annihilation in the supersymmetric framework. With the MAGIC telescope a search for a possible DM signal originating from Draco was performed during 2007. The analysis of the data results in a flux upper limit of 1.1x10^-11 photons cm^-2 sec^-1 for photon energies above 140 GeV, assuming a point like source. Furthermore, a comparison with predictions from supersymmetric models is given. While our results do not constrain the mSUGRA phase parameter space, a very high flux enhancement can be ruled out.Comment: Accepted for publication by Astrophysical Journa

    Constraints on the steady and pulsed very high energy gamma-ray emission from observations of PSR B1951+32/CTB 80 with the MAGIC Telescope

    Get PDF
    We report on very high energy gamma-observations with the MAGIC Telescope of the pulsar PSR B1951+32 and its associated nebula, CTB 80. Our data constrain the cutoff energy of the pulsar to be less than 32 GeV, assuming the pulsed gamma-ray emission to be exponentially cut off. The upper limit on the flux of pulsed gamma-ray emission above 75 GeV is 4.3*10^-11 photons cm^-2 sec^-1, and the upper limit on the flux of steady emission above 140 GeV is 1.5*10^-11 photons cm^-2 sec^-1. We discuss our results in the framework of recent model predictions and other studies.Comment: 7 pages, 7 figures, replaced with published versio
    corecore