417 research outputs found
Reddening, Absorption, and Decline Rate Corrections for a Complete Sample of Type Ia Supernovae leading to a Fully Corrected Hubble Diagram to v<30,000kms-1
Photometric BVI and redshift data corrected for streaming motions are
compiled for 111 "Branch normal", 4 1991T-like, 7 1991bg-like, and 2 unusual
SNe Ia. Color excesses E(B-V)host of normal SNe Ia, due to the absorption of
the host galaxy, are derived by three independent methods leading to the
intrinsic colors at maximum of (B-V)00=-0.024, and (V-I)00=-0.265 if normalized
to a common decline rate of Dm_15=1.1. The strong correlation between redshift
absolute magnitudes (based on Ho=60), corrected only for the extrinsic Galactic
absorption, and the derived E(B-V)host leads to well determined, yet abnormal
absorption-to-reddening ratios of R_BVI=3.65, 2.65, and 1.35. Comparison with
the canonical Galactic values of 4.1, 3.1, 1.8 forces the conclusion that the
law of interstellar absorption in the path length to the SN in the host galaxy
is different from the local Galactic law. Improved correlations of the fully
corrected absolute magnitudes with host galaxy type, decline rate, and
intrinsic color are derived. The four peculiar 1991T-type SNe are significantly
overluminous as compared to Branch-normal SNe Ia. The overluminosity of the
seven 1999aa-like SNe is less pronounced. The seven 1991bg-types in the sample
constitute a separate class of SNeIa, averaging in B two magnitudes fainter
than the normal Ia. New Hubble diagrams in BVI are derived out to ~30,000kms-1
using the fully corrected magnitudes and velocities, corrected for streaming
motions. Nine solutions for the intercept magnitudes in these diagrams show
extreme stability at the 0.04 level using various subsamples of the data. The
same precepts for fully correcting SN magnitudes we shall use for the
luminosity recalibration of SNe Ia in the forthcoming final review of our HST
Cepheid-SN experiment for the Hubble constant.Comment: 49 pages, 15 figures, 8 tables, accepted for publication in the
Astrophysical Journa
Visual search performance in cerebral visual impairment is associated with altered alpha band oscillations
Adding diphenyl diselenide in the diets of quails improves the quality of meat.
Abstract: Diphenyl diselenide (Ph2Se2) is an organic selenium compound that is known for its antioxidant characteristics. Thus, the aim of this study was to evaluate whether Ph2Se2 in quail (Coturnix japonica) diets influences the oxidative/antioxidant status and meat quality. Materials and methods. Four diets (0; 0.3; 0.6; 0.9 ppm Ph2Se2) were provided to 56 male quails (Coturnix japonica) distributed in a completely randomized design with 14 repetitions in order to check whether (PhSe)2 would change their blood and tissue oxidative/antioxidant status, which would lead to an improvement in the meat quality. Results. Adding Ph2Se2 in diets led to increased antioxidant activity of enzymes such as catalase, superoxide dismutase, and glutathione peroxidase, which consequently reduced oxidative levels in blood and tissues. Besides that, we observed an improvement in the quail meat quality; in other words, we observed an increased ability to hold water, a reduction in water loss from cooking, and reduced intensity of the yellow color in the breasts of birds that were fed with Ph2Se2. Conclusions. Therefore, we concluded that the antioxidant defense improvement in tissues that was provided by Ph2Se2 has a beneficial effect on meat quality. Resumen: El diseleniuro de difenilo (Ph2Se2) es un compuesto de selenio orgánico que es conocido por sus características antioxidantes. Por lo tanto, el objetivo de este estudio fue evaluar si Ph2Se2 en las dietas de codorniz (Coturnix japonica) influye en el estado oxidativo/antioxidante y la calidad de la carne. Materiales y métodos. Se proporcionaron cuatro dietas (0; 0.3; 0.6; 0.9 ppm Ph2Se2) a 56 codornices machos (Coturnix japonica) distribuidas en un diseño completamente aleatorizado con 14 repeticiones para verificar si Ph2Se2 cambiaría su sangre y tejido oxidativo/antioxidante, estado, lo que llevaría a una mejora en la calidad de la carne. Resultados. La adición de Ph2Se2 en las dietas provocó un aumento de la actividad antioxidante de enzimas como la catalasa, la superóxido dismutasa y la glutatión peroxidasa, lo que redujo los niveles de oxidación en la sangre y los tejidos. Además de eso, observamos una mejora en la calidad de la carne de codorniz; en otras palabras, observamos una mayor capacidad para retener agua, una reducción en la pérdida de agua debido a la cocción y una menor intensidad del color amarillo en las mamas de las aves que fueron alimentadas con Ph2Se2. Conclusiones. Por lo tanto, concluimos que la mejora de la defensa antioxidante en los tejidos proporcionada por Ph2Se2 tiene un efecto beneficioso sobre la calidad de la carne
Lysozyme affects the microbial catabolism of free arginine in raw-milk hard cheeses
Lysozyme (LZ) is used in several cheese varieties to prevent late blowing which results from fermentation
of lactate by Clostridium tyrobutyricum. Side effects of LZ on lactic acid bacteria population and free amino
acid pattern were studied in 16 raw-milk hard cheeses produced in eight parallel cheese makings
conducted at four different dairies using the same milk with (LZ\ufe) or without (LZ-) addition of LZ. The
LZ-cheeses were characterized by higher numbers of cultivable microbial population and lower amount
of DNA arising from lysed bacterial cells with respect to LZ \ufe cheeses. At both 9 and 16 months of
ripening, Lactobacillus delbrueckii and Lactobacillus fermentum proved to be the species mostly affected by
LZ. The total content of free amino acids indicated the proteolysis extent to be characteristic of the dairy,
regardless to the presence of LZ. In contrast, the relative patterns showed the microbial degradation of
arginine to be promoted in LZ \ufe cheeses. The data demonstrated that the arginine-deiminase pathway
was only partially adopted since citrulline represented the main product and only trace levels of ornithine
were found. Differences in arginine degradation were considered for starter and non-starter lactic
acid bacteria, at different cheese ripening stages
Bottom-up Fabrication and Atomic-Scale Characterization of Triply Linked, Laterally π-Extended Porphyrin Nanotapes**
Magnetic Interplay between π-Electrons of Open-Shell Porphyrins and d-Electrons of Their Central Transition Metal Ions
Positive Clinical Neuroscience: Explorations in Positive Neurology
Disorders of the brain and its sensory organs have traditionally been associated with deficits in movement, perception, cognition, emotion, and behavior. It is increasingly evident, however, that positive phenomena may also occur in such conditions, with implications for the individual, science, medicine, and for society. This article provides a selective review of such positive phenomena – enhanced function after brain lesions, better-than-normal performance in people with sensory loss, creativity associated with neurological disease, and enhanced performance associated with aging. We propose that, akin to the well-established field of positive psychology and the emerging field of positive clinical psychology, the nascent fields of positive neurology and positive neuropsychology offer new avenues to understand brain-behavior relationships, with both theoretical and therapeutic implications
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