The Soundings of the Antarctic Ship "Aurora" between Tasmania and the Antarctic Continent (1912)

Paper on and map of 'The Soundings of the Antarctic Ship "Aurora" between Tasmania and the Antarctic Continent (1912)' written by Captain J.K. Davis, published in The Geographical Journal, October 1913. Professor T.T. Flynn accompanied this voyage as biologist. RoySoc Serial G7.R9

Microfluidic and Nanofluidic Cavities for Quantum Fluids Experiments

The union of quantum fluids research with nanoscience is rich with opportunities for new physics. The relevant length scales in quantum fluids, 3He in particular, are comparable to those possible using microfluidic and nanofluidic devices. In this article, we will briefly review how the physics of quantum fluids depends strongly on confinement on the microscale and nanoscale. Then we present devices fabricated specifically for quantum fluids research, with cavity sizes ranging from 30 nm to 11 microns deep, and the characterization of these devices for low temperature quantum fluids experiments.Comment: 12 pages, 3 figures, Accepted to Journal of Low Temperature Physic

3D seismic imaging of buried Younger Dryas mass movement flows: Lake Windermere, UK

Windermere is a glacially overdeepened lake located in the southeastern Lake District, UK. Using the threedimensional(3D) Chirp subbottom profiler, we image mass movement deposits related to the Younger Dryas(YD) within a decimetre-resolution 3D seismic volume, documenting their internal structure and interactionwith preexisting deposits in unprecedented detail. Three distinct flow events are identified and mappedthroughout the 3D survey area. Package structures and seismic attributes classify them as: a small (totalvolume of c. 1500 m3) debris flow containing deformed translated blocks; a large (inferred total volume ofc. 500,000 m3), homogeneous fine-grained mass flow deposit; and a debris flow (inferred total volume ofc. 60,000 m3) containing small (c. 8.0×2.0 m) deformed translated blocks. Geomorphological mapping oftheir distribution and interaction with preexisting sediments permit the reconstruction of a depositionalhistory for the stratigraphic units identified in the seismic volume.<br/

Condensation of Hard Spheres Under Gravity: Exact Results in One Dimension

We present exact results for the density profile of the one dimensional array of N hard spheres of diameter D and mass m under gravity g. For a strictly one dimensional system, the liquid-solid transition occurs at zero temperature, because the close-pakced density, $\phi_c$, is one. However, if we relax this condition slightly such that $phi_c=1-\delta$, we find a series of critical temperatures T_c^i=mgD(N+1-i)/\mu_o with \mu_o=const, at which the i-th particle undergoes the liquid-solid transition. The functional form of the onset temperature, T_c^1=mgDN/\mu_o, is consistent with the previous result [Physica A 271, 192 (1999)] obtained by the Enskog equation. We also show that the increase in the center of mass is linear in T before the transition, but it becomes quadratic in T after the transition because of the formation of solid near the bottom

Quantum corrections to the dynamics of interacting bosons: beyond the truncated Wigner approximation

We develop a consistent perturbation theory in quantum fluctuations around the classical evolution of a system of interacting bosons. The zero order approximation gives the classical Gross-Pitaevskii equations. In the next order we recover the truncated Wigner approximation, where the evolution is still classical but the initial conditions are distributed according to the Wigner transform of the initial density matrix. Further corrections can be characterized as quantum scattering events, which appear in the form of a nonlinear response of the observable to an infinitesimal displacement of the field along its classical evolution. At the end of the paper we give a few numerical examples to test the formalism.Comment: published versio

Mucin gene expression during differentiation of human airway epithelia in vitro MUC4 and MUC5b are strongly induced

Mucus hypersecretion is characteristic of chronic airway diseases. However, regulatory mechanisms are poorly understood. Human airway epithelial cells grown on permeable supports at the air-liquid interface (ALI) develop a mucociliary morphology resembling that found in vivo. Such cultures provide a model for studying secretory cell lineage, differentiation, and function, and may provide insight regarding events leading to mucus hypersecretion. The mucin gene expression profile of well-differentiated human airway epithelial cells in culture has not yet been established. We compared expression of all the currently described mucin genes in poorly differentiated (conventional cultures on plastic) and well-differentiated (ALI) human nasal and bronchial epithelial cells. Differentiation-dependent upregulation of MUC3, MUC5AC, MUC5B, and MUC6 messenger RNA (mRNA) was demonstrated using reverse transcriptase-polymerase chain reaction (RT-PCR). Northern blot analysis showed a similar increase for MUC4 and demonstrated that induction of MUC4 and MUC5B expression depended on retinoic acid. MUC1, MUC2, MUC7, and MUC8 mRNAs were also detected by RT-PCR, but these genes did not appear to be strongly regulated as a function of differentiation. Mucin gene expression was similar in bronchial and nasal cells. Thus, mucociliary differentiation of human airway epithelia in vitro entails upregulation of several mucin genes

Light Lambda-Lambda Hypernuclei and the Onset of Stability for Lambda-Xi Hypernuclei

New Faddeev-Yakubovsky calculations for light Lambda-Lambda hypernuclei are presented in order to assess the self consistency of the Lambda-Lambda hypernuclear binding-energy world data and the implied strength of the Lambda-Lambda interaction, in the wake of recent experimental reports on Lambda-Lambda-4H and Lambda-Lambda-6He. Using Gaussian soft-core simulations of Nijmegen one-boson-exchange model interactions, the Nijmegen soft-core model NSC97 simulations are found close to reproducing the recently reported binding energy of Lambda-Lambda-6He, but not those of other species. For stranger systems, Faddeev calculations of light Lambda-Xi hypernuclei, using a simulation of the strongly attractive Lambda-Xi interactions due to the same model, suggest that Lambda-Xi-6He marks the onset of nuclear stability for Xi hyperons.Comment: 5 pages, 3 postscript figures; fig.2 replaced, minor changes, accepted as Rapid Communication in PR

Constraints on diffuse neutrino background from primordial black holes

We calculated the energy spectra and the fluxes of electron neutrino emitted in the process of evaporation of primordial black holes (PBHs) in the early universe. It was assumed that PBHs are formed by a blue power-law spectrum of primordial density fluctuations. We obtained the bounds on the spectral index of density fluctuations assuming validity of the standard picture of gravitational collapse and using the available data of several experiments with atmospheric and solar neutrinos. The comparison of our results with the previous constraints (which had been obtained using diffuse photon background data) shows that such bounds are quite sensitive to an assumed form of the initial PBH mass function.Comment: 18 pages,(with 7 figures

Geometric Entanglement of Symmetric States and the Majorana Representation

Permutation-symmetric quantum states appear in a variety of physical situations, and they have been proposed for quantum information tasks. This article builds upon the results of [New J. Phys. 12, 073025 (2010)], where the maximally entangled symmetric states of up to twelve qubits were explored, and their amount of geometric entanglement determined by numeric and analytic means. For this the Majorana representation, a generalization of the Bloch sphere representation, can be employed to represent symmetric n qubit states by n points on the surface of a unit sphere. Symmetries of this point distribution simplify the determination of the entanglement, and enable the study of quantum states in novel ways. Here it is shown that the duality relationship of Platonic solids has a counterpart in the Majorana representation, and that in general maximally entangled symmetric states neither correspond to anticoherent spin states nor to spherical designs. The usability of symmetric states as resources for measurement-based quantum computing is also discussed.Comment: 10 pages, 8 figures; submitted to Lecture Notes in Computer Science (LNCS