1,731 research outputs found
Unihemispheric sleep and asymmetrical sleep: behavioral, neurophysiological, and functional perspectives [Corrigendum]
No full textMascetti GG. Nat Sci Sleep. 2016;8:221–38.For references 147, 153 and 154 the lead author should be Vyazovskiy, not Wyazovskiy.Read the original articl
ASSIGNMENT OF , , and CONFORMERS IN THE ROTATIONAL SPECTRUM OF -PROPANOL
No full textAuthor Institution: Institute of Physics, Polish Academy of Sciences, Al. Lotnikow; 32/46, 02-668 Warszawa, Poland; Department of Physics, The Ohio State University, Columbus,; OH 43210Recent broadband measurements of the rotational spectrum of -propanol up to 375 GHz resulted in determination of precise spectroscopic constants for the conformer of this molecule.}, 428 (2006)} This is most likely the most stable conformer, although four other conformers are predicted to be very similar in energy. Assignment of some of these in cm-wave rotational spectra has previously been reported, but it was not possible to extend that work directly to mm-wave spectra. \vspace{0.2cm} Application of graphical Loomis-Wood techniques built into AABS}, 231 (2005)} and CAAARS}, 229 (2005)} spectral analysis packages eventually allowed successful assignment of the remaining four conformers: , , , and -propanol. It was realised that rotational energies in (, ) and (, ) pairs of conformers are highly coupled, but also amenable to description in terms of the Coriolis interaction mechanism. This allowed very precise determination of some energy level differences, such as cm. The assignment was checked against calculations, and is supported by new, precise determinations of dipole moments of some conformers, which were carried out using supersonic expansion cavity-FTMW spectroscopy
The long-wavelength view of GG Tau A: rocks in the ring world
No full textWe present the first detection of GG Tau A at centimetre wavelengths, made with the Arcminute Microkelvin Imager Large Array at a frequency of 16 GHz (λ = 1.8 cm). The source is detected at >6 σrms with an integrated flux density of S16GHz = 249 ± 45 µJy. We use these new centimetre-wave data, in conjunction with additional measurements compiled from the literature, to investigate the long-wavelength tail of the dust emission from this unusual protoplanetary system. We use an MCMC-based method to determine maximum likelihood parameters for a simple parametric spectral model and consider the opacity and mass of the dust contributing to the microwave emission. We derive a dust mass of Md ~ 0.1 Msun, constrain the dimensions of the emitting region and find that the opacity index at λ > 7 mm is less than unity, implying a contribution to the dust population from grains exceeding ~4 cm in size. We suggest that this indicates coagulation within the GG Tau A system has proceeded to the point where dust grains have grown to the size of small rocks with dimensions of a few centimetres. Considering the relatively young age of the GG Tau association in combination with the low derived disc mass, we suggest that this system may provide a useful test case for rapid core accretion planet formation models
Anisotropic Heisenberg Antiferromagnet With Arbitrary Dimensionality
No full textWe derive closed-form asymptotic expressions for the ground state, low-lying excitations, ground state energy, and short-range order parameter for the antiferromagnetic Heisenberg model in the quasi-Ising asymptotic limit. A general lattice with no frustration of the antiferromagnetic order is assumed. Comparisons with exact results in one- and numerical data in two-dimensions yield excellent agreement over a wide range of values of the anisotrpy parameter. © 1988.688743746Bednorz, Müller, (1986) Z. Phys. B, 64, p. 189Bethe, (1931) Z. Physik, 71, p. 205Orbach, (1958) Phys. Rev., 112, p. 309Vaknin, Sinha, Moncton, Johnston, Newsom, Safinya, King, Jr., (1987) Phys. Rev. Letters, 58, p. 2802Shirane, Endoh, Birgenau, Kastner, Hidaka, Oda, Suzuki, Murakami, (1987) Phys. Rev. Letters, 59, p. 1613T. Barnes, D. Kotchan and E.S. Swanson, University of Toronto preprint UTPT-88-09S. Tang and J.E. Hirsch, University of California at San Diego preprintE,. Dagotto and E. Moreo, University of Illinois preprint ILL-(TH)-88Lagos, Cabrera, (1988) Phys. Rev. B, 38, p. 657Lagos, Cabrera, (1988) Solid State Commun., 67, p. 221Lagos, Kiwi, Gagliano, Cabrera, (1988) Solid State Commun., 67, p. 22
Triangular Constellations in Flows
No full textParticles advected on the surface of a fluid can exhibit fractal clustering. The local structure of a fractal set is described by its dimension , which is the exponent of a power-law relating the mass in a ball to its radius : . It is desirable to characterise the {\em shapes} of constellations of points sampling a fractal measure, as well as their masses. The simplest example is the distribution of shapes of triangles formed by triplets of points, which we investigate for fractals generated by chaotic dynamical systems. The most significant parameter describing the triangle shape is the ratio of its area to the radius of gyration squared. We show that the probability density of has a phase transition: is independent of and approximately uniform below a critical flow compressibility , which we estimate. For the distribution appears to be described by two power laws: when , and when
Dynamic of large particles embedded in shear flows
No full textLarge particles () immersed in a closed turbulent flow tend to explore in a non-uniformly way the cavity in which they are placed. Here we study the slow dynamics of large particles (with various size) advected in closed turbulent flows at different Reynolds numbers. We investigate the spatial sampling experienced by large particles in two fully turbulent closed flows generated between counter-rotating disks (so called von Karman flow), focusing in the slow frequency's (, where is the rotation rate of the driving impellers) and characterize the power spectrum of the slow fluctuations of particles position. Both considered flows share a common feature : the presence of a shear region dividing two mean re-circulation regions ; however the spatial symmetries and the temporal behaviors of both setups are very different. The principal result in this research is that despite these differences both flows exhibit a well defined slow dynamical behavior that can be identified in Fourier space. We report on the universal characteristics of such slow motion
The Ground State Of The Heisenberg Antiferromagnetic Chain In The Quasi-ising Limit
No full textStarting from a closed-form ground state, recently proposed for the Heisenberg antiferromagnetic chain in the limit of high anisotropy, we derive formulae for the pair correlations to all orders in terms of the anisotropy parameter α (Ising:α = 0, isotropic: α = 1). Comparison with exact results for a chain of N = 20 sites, obtained from a computer calculation, shows excellent agreement for 0≤ α < 0.5. © 1988.673225228Jordan, Wigner, (1928) Z. Phys., 47, p. 631Spronken, Jullien, Avignon, (1981) Phys. Rev. B, 24, p. 5356Hubbard, (1978) Phys. Rev. B, 17, p. 494Lagos, Cabrera, (1988) Solid State Commun, 67, p. 221M. Lagos, M. Kiwi, and R. Ramírez, to be publishedGagliano, Proetto, Balseiro, (1987) Phys. Rev. B, 36, p. 2257Dagotto, Moreo, (1985) Phys. Rev. D, 31, p. 865Gagliano, Dagotto, Moreo, Alcaraz, (1986) Phys. Rev. B, 34, p. 1677Gagliano, Bacci, (1987) Phys. Rev. D, 36, p. 54
Lactobacillus rhamnosus GG Modulates Mitochondrial Function and Antioxidant Responses in an Ethanol-Exposed In Vivo Model: Evidence of HIGD2A-Dependent OXPHOS Remodeling in the Liver
No full textThe gut microbiota plays a central role in host energy metabolism and the development of metabolic disorders, partly through its influence on mitochondrial function. Probiotic supplementation, particularly with Lactobacillus rhamnosus GG, has been proposed as a strategy to modulate the microbiota and improve host metabolic health. Adolescent binge-like alcohol consumption is a critical public health issue known to induce neuroinflammation, oxidative stress, mitochondrial dysfunction, and intestinal dysbiosis, contributing to disorders such as alcoholic liver disease (ALD). This study aimed to evaluate the effects of L. rhamnosus GG supplementation on mitochondrial physiology in Sprague Dawley rats exposed to binge-like ethanol (BEP group) or saline (SP group) during adolescence (postnatal days 30–43). Starting on postnatal day 44, L. rhamnosus GG was administered orally for 28 days. Fecal colonization was confirmed by qPCR, and mitochondrial function was assessed in the liver, heart, and bone marrow through quantification of NADH, ATP, ADP/ATP ratio, total antioxidant capacity, and the expression of mitochondrial genes Higd2a, MnSOD1, and AMPKα1. L. rhamnosus GG supplementation induced tissue-specific mitochondrial adaptations. In the liver, it increased Higd2a expression and restored antioxidant and energy balance in ethanol-exposed rats. In the bone marrow, it reversed ethanol-induced metabolic stress and enhanced AMPKα1 expression. In contrast, in the heart, L. rhamnosus GG had minimal impact on mitochondrial energy markers but increased antioxidant capacity, indicating a more limited, redox-focused effect. These findings suggest that L. rhamnosus GG exerts context-dependent, tissue-specific benefits on mitochondrial physiology, primarily through the modulation of antioxidant defenses, activation of AMPKα1, and remodeling of respiratory complexes. This probiotic may represent a promising therapeutic strategy to mitigate mitochondrial dysfunction associated with early-life alcohol exposure
Soft gluon resummation in the signal-background interference process of gg(→ h ∗) → ZZ
No full textWe present a precise theoretical prediction for the signal-background interference process of gg(→ h ∗) → ZZ, which is useful to constrain the Higgs boson decay width and to measure Higgs couplings to the SM particles. The approximate NNLO K-factor is in the range of 2.05 − 2.45 (1.85 − 2.25), depending on M ZZ , at the 8 (13) TeV LHC. And the soft gluon resummation can increase the approximate NNLO result by about 10% at both the 8 TeV and 13 TeV LHC. The theoretical uncertainties including the scale, uncalculated multi-loop amplitudes of the background and PDF+αs are roughly O(10%) at NNLL′. We also confirm that the approximate K-factors in the interference and the pure signal processes are the same
- …
