248 research outputs found
effects of dietary vitamin e on the quality of table eggs enriched with n 3 long chain fatty acids
Abstract Because of the proposed cardioprotective benefits of n-3 fatty acids and vitamin E, a trial was carried out to investigate the possibility of enriching eggs with n-3 fatty acid and vitamin E added to the hen's diet. One hundred ninety-two Hy-Line Brown hens, 39-wk-old, were divided into eight groups: four groups received the basal diet supplemented with 3% lard and four doses of dl-alpha-tocopheryl acetate (0, 50, 100, and 200 ppm), whereas the diets of the other groups were supplemented with 3% of fish oil and the same doses of vitamin E. The performances of the hens and egg weights were not affected either by the type of lipid supplement or by the vitamin level. The treatment with fish oil caused a dramatic increase (
Full Understanding of Hot Electrons and Hot/Cold Holes in the Degradation of p-channel Power LDMOS Transistors
Degradation induced by hot-carrier stress is a crucial issue for the reliability of power LDMOS transistors. This is even more true for the p-channel LDMOS in which, unlike the n-channel counterpart, both the majority and minority carriers play a fundamental role on the device reliability. An in-depth study of the microscopic mechanisms induced by hot-carrier stress in new generation BCD integrated p-channel LDMOS is presented in this paper. The effect of the competing electron and hole trapping mechanisms on the on-resistance drift has been thoroughly analyzed. To this purpose, TCAD simulations including the deterministic solution of Boltzmann transport equation and the microscopic degradation mechanisms have been used, to the best of our knowledge, for the first time. The insight gained into the degradation sources and dynamics will provide a relevant basis for future device optimization
Increased efficacy of combining prebiotic and postbiotics approaches in mouse models relevant to autism and depression
The Microbiota-Gut-Brain axis (MGBA) is a bidirectional communication pathway between gut bacteria and the central nervous system (CNS) (including the intestine) that exerts a profound influence on neural development, neuroinflammation, activation of stress response and neurotransmission, in addition to modulating complex behaviours, such as sociability and anxiety. Several MGBA modulating approaches are possible, such as probiotic administration. A reasonable pharmacological approach would also be the contemporarily administration of both prebiotics and postbiotics. To test this hypothesis, we probed the effects of α-lactalbumin (ALAC; a prebiotic in the dose range of 125–500 mg/kg) and sodium butyrate (NaB; a postbiotic in the dose range of 30–300 mg/kg) alone and in combination. We used two animal behavioural models of idiopathic autism, (BTBR mice) and anxiety/depression (chronic unexpected mild stress - CUMS mice) respectively, using several standard behavioural paradigms such as Three-chamber social interaction test, Marble burying assay, depression-, anxiety- and memory-tests. In BTBR autistic mice, we found that both ALAC and NaB improve animal sociability, and memory in the passive avoidance (PA); drug combination was more effective in almost all tests also reducing immobility time in the forced swimming test (FST), which was not affected by single drug administration. Similarly, in the CUMS mice, single drug administration was effective in improving: 1) depressive-like behaviour in the FST and sucrose preference test; 2) memory and learning in the PA, novel object recognition and Morris water maze tests. Drug combination was again more effective than single drug administration in most cases; however, in the CUMS model, neither single drug or combination was effective in the elevated plus maze test for anxiety. Our results suggest that in both models, ALAC and NaB combination is more effective in improving some pathological aspects of animal behaviour than single administration and that the prebiotic/postbiotic approach should be considered a reasonable approach for the manipulation of the MGBA to improve efficacy
Symbiotic skin bacteria as a source for sex-specific scents in frogs
Amphibians are known to possess a wide variety of compounds stored in their skin glands. While significant progress has been made in understanding the chemical diversity and biological relevance of alkaloids, amines, steroids, and peptides, most aspects of the odorous secretions are completely unknown. In this study, we examined sexual variations in the volatile profile from the skin of the tree frog Boana prasina and combined culture and culture-independent methods to investigate if microorganisms might be a source of these compounds. We found that sesquiterpenes, thioethers, and methoxypyrazines are major contributors to the observed sex differences. We also observed that each sex has a distinct profile of methoxypyrazines, and that the chemical origin of these compounds can be traced to a Pseudomonas sp. strain isolated from the frog´s skin. This symbiotic bacterium was present in almost all individuals examined from different sites and was maintained in captive conditions, supporting its significance as the source of methoxypyrazines in these frogs. Our results highlight the potential relevance of bacteria as a source of chemical signals in amphibians and contribute to increasing our understanding of the role that symbiotic associations have in animals.Fil: Brunetti, AndrĂ©s Eduardo. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Nordeste. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Posadas | Universidad Nacional de Misiones. Instituto de BiologĂa Subtropical. Instituto de BiologĂa Subtropical - Nodo Posadas; Argentina. Universidade de Sao Paulo; BrasilFil: Lucio Lyra, Mariana. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Melo, Weilan G. P.. Universidade de Sao Paulo; BrasilFil: Andrade, Laura Elena. Universidade de Sao Paulo; BrasilFil: Palacios RodrĂguez, Pablo. Universidad de los Andes; ColombiaFil: Prado, Bárbara M.. Universidade de Sao Paulo; BrasilFil: Baptista Haddad, CĂ©lio Fernando. Universidade Estadual Paulista Julio de Mesquita Filho; BrasilFil: Tallarico Pupo, Monica. Universidade de Sao Paulo; BrasilFil: Peporine Lopes, Norberto. Universidade de Sao Paulo; Brasi
Elastic Chiral Waveguides with Gyro-Hinges
This article presents a novel chiral structure, consisting of Euler–Bernoulli beams connected to gyroscopic spinners.Anew type of boundary condition is introduced, which is referred to as a gyrohinge. In this system, flexural waves are coupled with rotational motion.Time-harmonic conditions are derived by assuming small nutation angles of the spinners. It is shown that the eigenfrequencies of a finite beam with gyro-hinges at one or both ends change dramatically with the moments of inertia and the spin and precession rates of the spinners. The formulation is then extended to elastic beams with periodically-spaced gyro-hinges, whose dispersion properties are investigated in detail. In particular, it is shown how stop-bands and standing modes are affected by the introduction of gyroscopic spinners at the junctions. It is also demonstrated that a periodic system composed of beams connected by gyro-hinges represents a good approximation of a gyrobeam, a theoretical structural element consisting of an elastic beam possessing a continuous distribution of stored angular momentum. The gyricity coefficient of a gyrobeam is then interpreted in terms of the physical parameters of the system of beams with gyroscopic spinners. This article opens a new perspective on the design and practical implementation of chiral mechanical systems
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