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Source-specific Fine Particulate Using Spatiotemporal Concentration Fields Developed using Chemical Transport Modelling and Data Assimilation
Brain neurons as quantum computers: {\it in vivo} support of background physics
The question: whether quantum coherent states can sustain decoherence,
heating and dissipation over time scales comparable to the dynamical timescales
of the brain neurons, is actively discussed in the last years. Positive answer
on this question is crucial, in particular, for consideration of brain neurons
as quantum computers. This discussion was mainly based on theoretical
arguments. In present paper nonlinear statistical properties of the Ventral
Tegmental Area (VTA) of genetically depressive limbic brain are studied {\it in
vivo} on the Flinders Sensitive Line of rats (FSL). VTA plays a key role in
generation of pleasure and in development of psychological drug addiction. We
found that the FSL VTA (dopaminergic) neuron signals exhibit multifractal
properties for interspike frequencies on the scales where healthy VTA
dopaminergic neurons exhibit bursting activity. For high moments the observed
multifractal (generalized dimensions) spectrum coincides with the generalized
dimensions spectrum calculated for a spectral measure of a {\it quantum} system
(so-called kicked Harper model, actively used as a model of quantum chaos).
This observation can be considered as a first experimental ({\it in vivo})
indication in the favour of the quantum (at least partially) nature of the
brain neurons activity
Finite-gap Solutions of the Vortex Filament Equation: Isoperiodic Deformations
We study the topology of quasiperiodic solutions of the vortex filament
equation in a neighborhood of multiply covered circles. We construct these
solutions by means of a sequence of isoperiodic deformations, at each step of
which a real double point is "unpinched" to produce a new pair of branch points
and therefore a solution of higher genus. We prove that every step in this
process corresponds to a cabling operation on the previous curve, and we
provide a labelling scheme that matches the deformation data with the knot type
of the resulting filament.Comment: 33 pages, 5 figures; submitted to Journal of Nonlinear Scienc
Mixing in a stratified shear flow: Energetics and sampling
Direct numerical simulations of the time evolution of homogeneous stably stratified shear flows have been performed for Richardson numbers from 0 to 1 and for Prandtl numbers between 0.1 and 2. The results indicate that mixing efficiency R(sub f) varies with turbulent Froude number in a manner consistent with laboratory experiments performed with Prandtl numbers of 0.7 and 700. However, unlike the laboratory results, for a particular Froude number, the simulations do not show a clear dependence on the magnitude of R(sub f) on Pr. The observed maximum value of R(sub f) is 0.25. When averaged over vertical length scales of an order of magnitude greater than either the overturning or Ozmidov scales of the flow, the simulations indicate that the dissipation rate epsilon is only weakly lognormally distributed with an intermittency of about 0.01 whereas estimated values in the ocean are 3 to 7
The Effects of Exposure to Endophyte-Infected Tall Fescue Seed on Faecal and Urine Concentrations of Ergovaline and Lysergic Acid in Mature Gelding Horses
Despite the good nutritive value of endophyte-infected tall fescue, consumption by livestock results in a decrease in both reproductive and growth performance due to ergot alkaloids produced by an endophytic fungus (Cross et al., 1995). Little research has investigated the metabolic fate of ergot alkaloids and/or their metabolites in grazing horses. Thus, the objectives of this experiment were: a) to determine concentrations of ergovaline (EV) and lysergic acid (LA) in the faeces and urine of geldings exposed to tall fescue seed over a time course experiment and b) to measure the effects of alkaloid-containing tall fescue on nutrient digestibility and serum clinical enzyme profiles
Non-ideality of quantum operations with the electron spin of a 31P donor in a Si crystal due to interaction with a nuclear spin system
We examine a 31P donor electron spin in a Si crystal to be used for the
purposes of quantum computation. The interaction with an uncontrolled system of
29Si nuclear spins influences the electron spin dynamics appreciably. The
hyperfine field at the 29Si nuclei positions is non-collinear with the external
magnetic field. Quantum operations with the electron wave function, i.e. using
magnetic field pulses or electrical gates, change the orientation of hyperfine
field and disturb the nuclear spin system. This disturbance produces a
deviation of the electron spin qubit from an ideal state, at a short time scale
in comparison with the nuclear spin diffusion time. For H_ext=9 T, the
estimated error rate is comparable to the threshold value required by the
quantum error correction algorithms. The rate is lower at higher external
magnetic fields.Comment: 11 pages, 2 figure
Longitudinal Body Composition Changes in NCAA Division I College Football Players
Many athletes seek to optimize body composition to fit the physical demands of their sport. American football requires a unique combination of size, speed, and power. The purpose of the current study was to evaluate longitudinal changes in body composition in Division I collegiate football players. For 57 players (Mean ± SD; Age=19.5 ± 0.9 yrs; Height=186.9 ± 5.7 cm; Weight=107.7 ± 19.1 kg), body composition was assessed via dual-energy x-ray absorptiometry in the off-season (March-Pre), end of off-season (May), mid-July (Pre-Season), and the following March (March-Post). Outcome variables included weight, body fat percentage (BF%), fat mass (FM), lean mass (LM), android (AND) and gynoid (GYN) fat, bone mineral content (BMC), and bone density (BMD). For a subset of athletes (n=13 out of 57), changes over a 4-year playing career were evaluated with measurements taken every March. Throughout a single year, favorable changes were observed for BF% (Δ=−1.3 ± 2.5%), LM (Δ=2.8 ± 2.8 kg), GYN (Δ=−1.5 ± 3.0%), BMC (Δ=0.06 ± 0.14 kg), and BMD (Δ=0.015 ± 0.027g·cm−2; all p<0.05). Across four years, weight increased significantly (Δ=6.6 ± 4.1kg), and favorable changes were observed for LM (Δ=4.3 ± 3.0 kg), BMC (Δ=0.18 ± 0.17 kg), and BMD (Δ=0.033 ± 0.039 g·cm−2; all p<0.05). Similar patterns in body composition changes were observed for linemen and non-linemen. Results indicate that well-trained collegiate football players at high levels of competition can achieve favorable changes in body composition, even late in the career, which may confer benefits for performance and injury prevention
Holographic Lithography
This review summarises the work of the Durham-Sheffield, UK team working on Holographic Lithography over the last decade. It collates progress in 3D resolution and overall scale of the substrate wiring patterns designed and considers a range of approaches and applications
Rotational symmetry of self-similar solutions to the Ricci flow
Let (M,g) be a three-dimensional steady gradient Ricci soliton which is
non-flat and \kappa-noncollapsed. We prove that (M,g) is isometric to the
Bryant soliton up to scaling. This solves a problem mentioned in Perelman's
first paper.Comment: Final version, to appear in Invent. Mat
Evaluating academic and media nongovernmental organization partnerships for participatory data gathering
This article discusses participatory methods for data gathering in the context of a partnership between a Swiss-based media development organization, Fondation Hirondelle, and a research team at the University of Sheffield. In 2018–2019, the partnership conducted fieldwork which focused on the impact of radio on women listeners in Niger. The project used participatory methods of data gathering in the form of workshops and focus group discussions (FGDs). The article examines the advantages and limitations of combining the practical experience of international development organizations and the in-depth research capabilities of academia. To triangulate this collaboration and to navigate the limitations of FGDs, the use of workshops is discussed as an important method for providing feedback among the radio practitioners and experts in Niger. The article examines the usefulness of combining these methods and reshaping their application to promote participatory research with radio audiences and practitioners
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