Facile and rapid synthesis of highly luminescent nanoparticles via Pulsed Laser Ablation in Liquid

This paper demonstrates the usefulness of pulsed laser ablation in liquids as a fast screening synthesis method able to prepare even complex compositions at the nanoscale. Nanoparticles of Y2O3:Eu3+, Lu2O2S: Eu3+, Gd2SiO5:Ce3+ and Lu3TaO7:Gd3+,Tb3+ are successfully synthesized by pulsed laser ablation in liquids. The phase and stoichiometries of the original materials are preserved while the sizes are reduced down to 5-10 nm. The optical properties of the materials are also preserved but show some small variations and some additional structures which are attributed to the specificities of the nanoscale (internal pressure, inhomogeneous broadening, surface states...

Shells of crystal field symmetries evidenced in oxide nano-crystals

By the use of a point charge model based on the Judd-Ofelt transition theory, the luminescence from Eu3+ ions embedded in Gd2O3 clusters is calculated and compared to the experimental data. The main result of the numerical study is that without invoking any other mechanisms such as crystal disorder, the pure geometrical argument of the symmetry breaking induced by the particle surface has influence on the energy level splitting. The modifications are also predicted to be observable in realistic conditions where unavoidable size dispersion has to be taken into account. The emission spectrum results from the contribution of three distinct regions, a cluster core, a cluster shell and a very surface, the latter being almost completely quenched in realistic conditions. Eventually, by detailing the spectra of the ions embedded at different positions in the cluster we get an estimate of about 0.5 nm for the extent of the crystal field induced Stark effect. Due to the similarity between Y2O3 and Gd2O3, these results apply also to Eu3+ doped Y2O3 nanoparticles

Average output entropy for quantum channels

We study the regularized average Renyi output entropy \bar{S}_{r}^{\reg} of quantum channels. This quantity gives information about the average noisiness of the channel output arising from a typical, highly entangled input state in the limit of infinite dimensions. We find a closed expression for \beta_{r}^{\reg}, a quantity which we conjecture to be equal to \Srreg. We find an explicit form for \beta_{r}^{\reg} for some entanglement-breaking channels, and also for the qubit depolarizing channel $\Delta_{\lambda}$ as a function of the parameter $\lambda$. We prove equality of the two quantities in some cases, in particular we conclude that for $\Delta_{\lambda}$ both are non-analytic functions of the variable $\lambda$.Comment: 32 pages, several plots and figures; positivity condition added for Theorem on entanglement breaking channels; new result for entrywise positive channel

Efficacy of turmeric (Curcuma longa) to ameliorate the adverse effects of T-2 toxin in broiler chicks

Abstract only availableA 3-wk feeding study was conducted to evaluate the efficacy of turmeric (Curcuma longa) powder (TMP), containing a known level of curcumin to ameliorate the adverse effects of T-2 toxin in broiler chicks. Five pen replicates of 5 chicks each were assigned to each of 6 dietary treatments. Dietary treatments evaluated include: 1) basal diet containing no T-2 toxin or TMP; 2) basal diet supplemented with 0.67% TMP containing 220 mg/kg total curcuminoids (TCMN); 3) basal diet supplemented with 1 mg/kg T-2; 4) basal diet supplemented with 1 mg/kg T-2 and 220 mg/kg TCMN; 5) basal diet supplemented with 2 mg/kg T-2; 6) and basal diet supplemented with 2 mg/kg T-2 and 220 mg/kg TCMN. The addition of T-2 toxin or TCMN to the diet had no effect (P > 0.05) on feed intake, body weight gain, or feed conversion which averaged 870g, 685g, and 1.29 g:g, respectively, across all treatments. Similarly, there was no effect (P > 0.05) of T-2 or TCMN on relative liver weight which averaged 3.07g across all treatments. Results indicate that 2 mg/kg T-2 was not toxic to broiler chicks fed dietary treatments for 3 weeks. Results also indicate that the addition of 220 mg/kg TCMN to the basal diet was not beneficial to chicks. It remains to be seen if T-2 toxin negatively affected the antioxidant status and hepatic gene expression of chicks, and if TCMN was beneficial in ameliorating any observed negative effects. Samples are currently being analyzed for antioxidant activity and changes in gene expression.Gyeongsang National Universit

Evaluation of the efficacy of test products to ameliorate the toxic effects of aflatoxin present in broiler chick diets

Abstract only availableAn in vivo study was conducted to evaluate the efficacy of several adsorbent test products to ameliorate the toxic effects of aflatoxin B1 (AFB1) in chicks. Ninety day-old straight run chicks were purchased from a commercial hatchery, weighed, wing-banded, and assigned to floor pens. A completely randomized design was used with 10 chicks (chick was experimental unit) assigned to each of 9 dietary treatments from hatch to 28 days. The aflatoxin used for this study was supplied by Aspergillus parasiticus (NRRL-2999) culture material (815 mg AFB1/kg). The dietary treatments included: 1) basal diet containing no AFB1); 2) basal diet supplemented with 1.5 mg AFB1 /kg diet; 3) As diet 2 plus Product 1; 4) As diet 2 plus Product 2; 5) As diet 2 plus Product 3; 6) As diet 2 plus Product 4; 7) As diet 2 plus Product 5; 8) As diet 2 plus Product 6; and 9) As diet 2 plus Product 7. The addition of Products 1, 2, 3, 4, 5, and 6 to AF diets did not prevent the reduction in body weight gain (BWG) due to AFB1. Chicks fed diets containing Products 1 thru 6 all had lower BWG (P >.05) compared with control chicks. Body weight gain of birds fed Product 7 was not significantly different (P > .05) from the birds fed the positive control; however, it was also not significantly different (P >.05) from birds fed AF B1 alone. Relative liver weights were not affected by dietary treatments (P > .05) and averaged 3.06 g/100g body weight across all treatments. Results of this study indicate that none of these products were effective in ameliorating the toxic effects of AFB1.Louis Stokes Missouri Alliance for Minority Participatio

Efficacy of high levels of microbial phytase in improving phytate Phosphorus utilization by turkeys

Abstract only availableA 14-day study was conducted with 750 female turkey poults to determine the efficacy of high levels of phytase in improving turkey performance and percent and milligram toe ash. Six dietary treatments were assigned to five replicate pens of 25 poults each. A National Research Council (NRC) corn-soybean meal diet, adequate in all nutrients, was fed to all birds for the first week. Dietary treatments fed from 8 to 21 days of age included: 1) a positive control NRC diet (0.6% non-phytate phosphorus [npP] and 1.2% Ca); 2) a low P negative control basal diet (B) (0.36% npP and 1.01% Ca); 3) B + 250 U/kg phytase; 4) B + 500 U/kg phytase; 5) B + 10,000 U/kg phytase; and 6) B + 20,000 U/kg phytase. Feed intake and body weight gain were significantly higher (P .05) to the NRC positive control diet but significantly higher (P < .05) than the negative control birds (diet 2). Milligrams of toe ash was also significantly higher (P < .05) for the birds fed the highest two levels of phytase compared to the birds fed the other diets. Feeding high levels of phytase (≥10,000 U/kg) to turkeys was effective in increasing phytate phosphorus utilization and in improving growth performance above the birds fed the NRC control diet.F.B. Miller Undergraduate Research Program in Animal Science

Efficacy of curcumin in ameliorating the toxic effects of ochratoxin A and aflatoxin in young broilers [abstract]

Abstract only availableTwo experiments (hatch to 21 days) were conducted to evaluate the efficacy of curcumin to ameliorate the toxic effects of aflatoxin (AF; Exp.1) and ochratoxin A (OA; Exp. 2). Food grade turmeric powder (Curcuma longa) containing 2.55% (Exp. 1) and 1.90% (Exp. 2) total curcuminoids (TCMN) was the source of curcumin. In Exp. 1, six pen replicates of 5 chicks each were assigned to each of 6 dietary treatments: A) basal diet with no TCMN or AF (BD); B) BD plus 444 mg/kg TCMN;C) BD plus 1.0 mg/kg AF; D) BD plus 74 mg/kg TCMN and 1.0 mg/kg AF;E) BD plus 222 mg/kg TCMN and 1.0 mg/kg AF; and F) BD plus 444 mg/kg TCMN and 1.0 mg/kg AF. Compared with controls, the addition of 1 mg/kg AF to the basal diet decreased (P < 0.05) feed intake (FI) and weight gain (WG). The addition of 74 and 222 mg/kg TCMN to the AF diet improved (P < 0.05) WG. In Exp. 2, five pen replicates of 5 chicks each were assigned to each of 5 dietary treatments: A) basal diet with no TCMN or OA (BD); B) BD plus 2.5 mg OA/kg diet; C) BD plus 2.5 mg OA/kg and 75 mg/kg TCMN; D) BD plus 2.5 mg OA/kg and 150 mg/kg TCMN; and E) BD plus 2.5 mg OA/kg diet and 225 mg/kg TCMN. Compared to controls, chicks fed OA had reduced (P < 0.001) feed FI and WG. The addition of up to 225 mg/kg to the OA diet was not effective in preventing the toxic effects of OA. Addition of 222 mg/kg TCMN to the AF diet was partially effective in protecting chicks from the toxic effects of AF, but 225 mg/kg TCMN was not effective in protecting chicks from the toxic effects of OA.CAFNR On Campus Research Internshi

Beta-Adrenergic Receptors in the Lateral Nucleus of the Amygdala Contribute to the Acquisition but Not the Consolidation of Auditory Fear Conditioning

Beta-adrenergic receptors (βARs) have long been associated with fear disorders and with learning and memory. However, the contribution of these receptors to Pavlovian fear conditioning, a leading behavioral model for studying fear learning and memory, is still poorly understood. The aim of this study was to investigate the involvement of βAR activation in the acquisition, consolidation and expression of fear conditioning. We focused on manipulations of βARs in the lateral nucleus of the amygdala (LA) because of the well-established contribution of this area to fear conditioning. Specifically, we tested the effects of intra-LA microinfusions of the βAR antagonist, propranolol, on learning and memory for auditory Pavlovian fear conditioning in rats. Pre-training propranolol infusions disrupted the initial acquisition, short-term memory (STM), and long-term memory (LTM) for fear conditioning, but infusions immediately after training had no effect. Further, infusion of propranolol prior to testing fear responses did not affect fear memory expression. These findings indicate that amygdala βARs are important for the acquisition but not the consolidation of fear conditioning

Time-dependent Turbulence in Stars

Three-dimensional (3D) hydrodynamic simulations of shell oxygen burning (Meakin and Arnett 2007) exhibit bursty, recurrent fluctuations in turbulent kinetic energy. These are shown to be due to a global instability in the convective region, which has been suppressed in calculations of stellar evolution which use mixing-length theory (MLT). Quantitatively similar behavior occurs in the model of a convective roll (cell) of Lorenz (1963), which is known to have a strange attractor that gives rise to random fluctuations in time.An extension of the Lorenz model, which includes Kolmogorov damping and nuclear burning, is shown to exhibit bursty, recurrent fluctuations like those seen in the 3D simulations. A simple model of a convective layer (composed of multiple Lorenz cells) gives luminosity fluctuations which are suggestive of irregular variables (red giants and supergiants, Schwarzschild 1975). Apparent inconsistencies between Arnett, Meakin, and Young (2009) and Nordlund, Stein, and Asplund (2009) on the nature of convective driving have been resolved, and are discussed.Comment: 8 pages, 2 figures, IAU Symposium 271 "Astrophysical Dynamics: From Galaxies to Stars", Nice, FR, 201

Cathédrales, une approche immersive à la composition d'une musique spatialisée en 3D : intentions, stratégies et réceptions

Mémoire en recherche-créationL’expérience sonore immersive est souvent associée à la spatialisation du son. Mais, le phénomène d’immersion est plutôt complexe et le réduire au seul emploi d’un dispositif technique ne permet pas d’en apprécier les causes multiples sur le plan de la réception. Ce mémoire présente un projet de recherche-création intitulé Cathédrales, dont l’objectif est de mieux comprendre la réception d’une œuvre de musique acousmatique spa- tialisée en 3D et intentionnellement immersive. Ce travail porte notamment sur les stratégies de composition adoptées et leurs effets, au regard des intentions de départs et de l’analyse des commentaires émis par un ensemble d’auditeurs-participants. Les trois premiers chapitres présentent les aspects conceptuels soutenant la démarche de création des œuvres Ville Aux Cent Clochers et Réverbérence. Le premier chapitre vise à préciser d’entrée de jeu ce que signifie l’immersion sonore, de sa compréhension plus générale jusqu’à ses significations plus particulières; le deuxième chapitre présente ensuite l’immersion sous l’angle d’une narratologie naturelle de la musique; tandis que le troisième chapitre intègre cette approche narrative au langage du cinéma pour l’oreille et adapte le tout au contexte multidirectionnel du médium de diffusion sonore. Les deux parties qui composent l’œuvre Cathédrales : I. Ville Aux Cent Clochers et II. Réverbérence, sont présentées au quatrième chapitre. Après avoir introduit le propos de l’œuvre dans son ensemble, les intentions et les stratégies spécifiques à chacune de ces pièces y sont également développées. Enfin, le cinquième chapitre présente les résultats de deux études de réception, impliquant un certain nombre d’auditeurs, sur l’écoute de musiques spatialisées pour dôme de haut-parleurs. L’analyse esthésique découlant de ces enquêtes permet de proposer différentes catégories conceptuelles de l’expérience sonore immersive. Ces catégories peuvent éventuellement servir à schématiser les effets de certaines stratégies de composition, combinées à l’emploi d’un dispositif technologique particulier, sur la réception d’une musique spatialisée en 3D.The immersive sound experience is often associated with sound spatialization. But the immersive phenomenon is rather complex and reducing it to the sole usage of a technical device does a disservice to our appreciation of its multiple causes in terms of a work’s reception. This memoir presents a research-creation project, entitled Cathédrales, that aims to better understand the reception of an intentionally immersive 3Dspatialized acousmatic music. This work focuses on the adopted compositional strategies and their effects, with regard to initial intentions and the analysis of comments made by listener participants. The first three chapters present the concepts underlying the creative process for the works Ville Aux Cent Clochers ("City of a hundred bell towers") and Réverbérence ("Reverberence"). The first chapter clarifies the meaning of sound immersion from the outset, from its more general understanding to its more specific meanings; the second chapter then presents immersion under the scope of a natural narratology of music; while the third chapter integrates such narrative approach within the language of a "cinema for the ear", while adapting it to the multidirectional context of the sound diffusion medium. In the fourth chapter are presented the two parts composing Cathédrales ("Cathedrals") : I. Ville Aux Cent Clochers and II. Réverbérence. After introducing the concept of the work as a whole, the intentions and strategies that are more specific to each part of the work are then exposed. Finally, the fifth chapter presents the results of two case studies on the reception behaviors of multiple participants listening to spatialized music over a loudspeakers dome. Aesthesic analysis arising from these surveys allows to provide different conceptual categories of the immersive sound experience. Such categorization may eventually serve to schematize the effects of certain compositional strategies, in combination with the usage of a particular technological device, on the reception of 3D spatialized music