Infrared characterization of silicon carbide nanowires

Silicon carbide nanowires have been obtained via combustion synthesis route. X-ray diffraction analysis confirmed that the synthesized material is the 3C polytype of silicon carbide with zincblende unit cell. Detailed investigations of such SiC 1D nanostructures were carried out exploiting Fourier transform infrared spectroscopy. IR measurements we performed using BRUKER HYPERION FT-IR microscope. For the purpose of comparison, a series of powder samples were examined, including raw synthesis product, purified SiC nanowires and several commercially available microand nanopowders (from Alpha Aesar and PlasmaChem). Comprehensive comparative analysis of the MIR spectra has been performed. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/2063

Desarrollo de barra de nuez pecan con cereales

La nuez pecan (Carya illinoinensis) se comercializa entera (con cáscara) o pelada, en forma de mariposa. Dado que, durante la obtención de nuez sin cáscara, se produce generalmente la ruptura de la mariposa, se origina en consecuencia un subproducto con menor valor de comercialización. Sin embargo, la mariposa rota podría ser aprovechada como insumo para la formulación de alimentos de buena calidad nutricional. El objetivo del presente trabajo fue encontrar una alternativa comercial para este subproducto, mediante el desarrollo de una barra de cereal que contenga nueces partidas de pecan. Las mismas, provistas por la estación experimental INTA-Delta, fueron utilizadas como componente mayoritario de los ingredientes sólidos en la formulación. Para tal fin, se diseñó un equipo para producir barras de cereal para pequeños emprendedores. Se desarrolló una formulación básica de barra (símil barra de cereal) utilizando como componentes mayoritarios nuez pecan, trigo inflado azucarado y arroz inflado azucarado. El proceso para la elaboración de la barra de nuez pecan consistió en la preparación del aglutinante (a partir de azúcar blanca, acetite de girasol, jarabe de maltosa y agua) en una paila de acero inoxidable de fondo esferoide, con quemador a gas, hasta alcanzar los 115 °C. A continuación de la incorporación de los ingredientes sólidos, la mezcla se trasvaso a una bandeja rectangular y, luego de la solidificación de la mezcla, se cortaron las barras de cereal (aproximadamente con un peso de 15g c/u). Para la caracterización química de las mismas se midieron los siguientes parámetros: contenido de humedad, cenizas, proteínas, lípidos totales, perfil de ácidos grasos por GC-FID. Se determinó además el contenido de tocoferoles por HPLC-RF en fase reversa con detección de fluorescencia. Se analizó el contenido de fenoles totales por el método de Folin- iocalteu, taninos condensados por el método de la Vainillina y capacidad antioxidante por el método del DPPH. A partir de las determinaciones nutricionales, se calculó el valor energético de la barra de cereal. De acuerdo con las determinaciones, el producto obtenido representa unos 71,85 kcal por unidad, con un aporte de proteínas de 6,1%, 32,9% de grasas totales y 57,1% de hidratos de carbono. El perfil de ácidos grasos se caracterizó por un bajo contenido de ácidos grasos saturados (10%), mientras que el contenido de ácidos grasos insaturados fue elevado (90%), predominando el ácido oleico (66%). Respecto de las vitaminas y compuestos antioxidantes, las barras presentaron un contenido de 0,26 mg de tocoferoles, aportado principalmente por γ-tocoferol; 20,4 mg de catequina equivalente por g muestra en la cuantificación de polifenoles totales y una actividad antioxidante total de 18,8 mg de trolox equivalente por gramo. Los resultados obtenidos indican que este producto constituye una fuente importante de ácidos grasos saludables, así como de vitaminas antioxidantes, destacando sus cualidades nutricionales, además de ofrecer una alternativa de comercialización a la producción de un cultivo regional de creciente importancia, agregando valor al producto base.The pecan nut (Carya illinoinensis) is sold whole (with shell) or peeled, in the form of a butterfly. During the production of shelled walnuts, and because of the ruptures underwent by the butterflies, a by-product with a lower commercialization value is usually obtained. However, the broken butterfly can be used for the formulation of foods with good nutritional quality. The objective of the present work was to find a commercial alternative for this by-product, through the development of a cereal bar containing split pecan nuts. The nuts 48 were provided by the INTA-Delta Experimental Station, were used as a major component of the solid ingredients in the formulation. For this purpose, pilot equipment was designed to produce cereal bars for small entrepreneurs. A basic bar formulation (cereal bar simile) was developed using as a major component pecan nut, sweetened puffed wheat and sweetened puffed rice. The process for the preparation of the pecan nut bar consisted in the preparation of the binder (from white sugar, sunflower oil, maltose syrup and water) in a stainless steel pan with spherical bottom with gas burner until reaching the 115 °C. After the solid ingredients were incorporated, the mixture was transferred into a rectangular tray, and after the solidification, the cereal bars were cut (approximately weighing 15 g each). For the chemical characterization, different parameters were determined: moisture content, ash and proteins, total lipids, fatty acid profile by GC-FID. The content of tocopherols was also determined by reverse phase HPLC-RF with fluorescence detection. The content of total phenols was analyzed by the Folin-Ciocalteu method, tannins condensed by the Vanillin method and antioxidant capacity by the DPPH method. From the nutritional determinations, the energy value of the cereal bar was calculated. The product obtained represents 71.85 kcal per unit, with a protein content of 6.1%, 32.9% of total fats and 57.1% of carbohydrates. The fatty acid profile was characterized by a low content of saturated fatty acids (10%), while the content of unsaturated fatty acids was high (90%), with oleic acid predominating (66%). Regarding the vitamins and antioxidant compounds, the bars contains 0.26 mg of tocopherols, mainly in the form of γ-tocopherol; 20.4 mg of equivalent catechin per g sample in the quantification of total polyphenols and a total antioxidant activity of 18.8 mg of equivalent trolox per gram. The results indicate that this product represents an important source of healthy fatty acids, as well as of antioxidant vitamins, highlighting their nutritional qualities, but also offering an alternative for the successful marketing of the production of a growing regional crop, adding value to the base product.Fil: Guidi, Silvina Mabel. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Tecnología de Alimentos; Argentina. Universidad de Morón. Facultad de Agronomía y Ciencias Agroalimentarias; Argentina.Fil: Gomez, Andrea Gisella. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Tecnología de Alimentos; Argentina.Fil: Polenta, Gustavo Alberto. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Tecnología de Alimentos; Argentina.Fil: Lopez, M. C. Instituto Nacional de Tecnología Industrial. Centro de Agroalimentos. Coordinación de Oleaginosas y Subproductos; Argentina.Fil: Blasco, R. Instituto Nacional de Tecnología Industrial. Centro de Agroalimentos. Coordinación de Cereales, Harinas y Productos Derivados; Argentina

Down syndrome-recent progress and future prospects

Down syndrome (DS) is caused by trisomy of chromosome 21 (Hsa21) and is associated with a number of deleterious phenotypes, including learning disability, heart defects, early-onset Alzheimer's disease and childhood leukaemia. Individuals with DS are affected by these phenotypes to a variable extent; understanding the cause of this variation is a key challenge. Here, we review recent research progress in DS, both in patients and relevant animal models. In particular, we highlight exciting advances in therapy to improve cognitive function in people with DS and the significant developments in understanding the gene content of Hsa21. Moreover, we discuss future research directions in light of new technologies. In particular, the use of chromosome engineering to generate new trisomic mouse models and large-scale studies of genotype-phenotype relationships in patients are likely to significantly contribute to the future understanding of DS

A First Search for coincident Gravitational Waves and High Energy Neutrinos using LIGO, Virgo and ANTARES data from 2007

We present the results of the first search for gravitational wave bursts associated with high energy neutrinos. Together, these messengers could reveal new, hidden sources that are not observed by conventional photon astronomy, particularly at high energy. Our search uses neutrinos detected by the underwater neutrino telescope ANTARES in its 5 line configuration during the period January - September 2007, which coincided with the fifth and first science runs of LIGO and Virgo, respectively. The LIGO-Virgo data were analysed for candidate gravitational-wave signals coincident in time and direction with the neutrino events. No significant coincident events were observed. We place limits on the density of joint high energy neutrino - gravitational wave emission events in the local universe, and compare them with densities of merger and core-collapse events.Comment: 19 pages, 8 figures, science summary page at http://www.ligo.org/science/Publication-S5LV_ANTARES/index.php. Public access area to figures, tables at https://dcc.ligo.org/cgi-bin/DocDB/ShowDocument?docid=p120000

The Italian arm of the PREPARE study: an international project to evaluate and license a maternal vaccine against group B streptococcus.

BACKGROUND: Group B streptococcus (GBS) is a leading cause of sepsis, pneumonia and meningitis in infants, with long term neurodevelopmental sequelae. GBS may be associated with poor pregnancy outcomes, including spontaneous abortion, stillbirth and preterm birth. Intrapartum antibiotic prophylaxis (IAP) is currently the only way to prevent early-onset disease (presenting at 0 to 6 days of life), although it has no impact on the disease presenting over 6 days of life and its implementation is challenging in resource poor countries. A maternal vaccine against GBS could reduce all GBS manifestations as well as improve pregnancy outcomes, even in low-income countries. MAIN BODY: The term "PREPARE" designates an international project aimed at developing a maternal vaccination platform to test vaccines against neonatal GBS infections by maternal immunization. It is a non-profit, multi-center, interventional and experimental study (promoted by the St George University of London. [UK]) with the aim of developing a maternal vaccination platform, determining pregnancy outcomes, and defining the extent of GBS infections in children and mothers in Africa. PREPARE also aims to estimate the protective serocorrelates against the main GBS serotypes that cause diseases in Europe and Africa and to conduct two trials on candidate GBS vaccines. PREPARE consists of 6 work packages. In four European countries (Italy, UK, Netherlands, France) the recruitment of cases and controls will start in 2020 and will end in 2022. The Italian PREPARE network includes 41 centers. The Italian network aims to collect: GBS isolates from infants with invasive disease, maternal and neonatal sera (cases); cord sera and GBS strains from colonized mothers whose infants do not develop GBS infection (controls). SHORT CONCLUSION: PREPARE will contribute information on protective serocorrelates against the main GBS serotypes that cause diseases in Europe and Africa. The vaccine that will be tested by the PREPARE study could be an effective strategy to prevent GBS disease

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

All-sky search for long-duration gravitational wave transients with initial LIGO

We present the results of a search for long-duration gravitational wave transients in two sets of data collected by the LIGO Hanford and LIGO Livingston detectors between November 5, 2005 and September 30, 2007, and July 7, 2009 and October 20, 2010, with a total observational time of 283.0 days and 132.9 days, respectively. The search targets gravitational wave transients of duration 10-500 s in a frequency band of 40-1000 Hz, with minimal assumptions about the signal waveform, polarization, source direction, or time of occurrence. All candidate triggers were consistent with the expected background; as a result we set 90% confidence upper limits on the rate of long-duration gravitational wave transients for different types of gravitational wave signals. For signals from black hole accretion disk instabilities, we set upper limits on the source rate density between 3.4×10-5 and 9.4×10-4 Mpc-3 yr-1 at 90% confidence. These are the first results from an all-sky search for unmodeled long-duration transient gravitational waves. © 2016 American Physical Society

Search for Tensor, Vector, and Scalar Polarizations in the Stochastic Gravitational-Wave Background

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individually unresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically polarized gravitational waves. We find no evidence for a background of any polarization, and place the first direct bounds on the contributions of vector and scalar polarizations to the stochastic background. Under log-uniform priors for the energy in each polarization, we limit the energy densities of tensor, vector, and scalar modes at 95% credibility to Ω0T<5.58×10-8, Ω0V<6.35×10-8, and Ω0S<1.08×10-7 at a reference frequency f0=25 Hz. © 2018 American Physical Society

Search for gravitational waves from Scorpius X-1 in the second Advanced LIGO observing run with an improved hidden Markov model

We present results from a semicoherent search for continuous gravitational waves from the low-mass x-ray binary Scorpius X-1, using a hidden Markov model (HMM) to track spin wandering. This search improves on previous HMM-based searches of LIGO data by using an improved frequency domain matched filter, the J-statistic, and by analyzing data from Advanced LIGO's second observing run. In the frequency range searched, from 60 to 650 Hz, we find no evidence of gravitational radiation. At 194.6 Hz, the most sensitive search frequency, we report an upper limit on gravitational wave strain (at 95% confidence) of h095%=3.47×10-25 when marginalizing over source inclination angle. This is the most sensitive search for Scorpius X-1, to date, that is specifically designed to be robust in the presence of spin wandering. © 2019 American Physical Society

Erratum: "A Gravitational-wave Measurement of the Hubble Constant Following the Second Observing Run of Advanced LIGO and Virgo" (2021, ApJ, 909, 218)

[no abstract available