Acoustic suspension system

An acoustic levitation system is described, with single acoustic source and a small reflector to stably levitate a small object while the object is processed as by coating or heating it. The system includes a concave acoustic source which has locations on opposite sides of its axis that vibrate towards and away from a focal point to generate a converging acoustic field. A small reflector is located near the focal point, and preferably slightly beyond it, to create an intense acoustic field that stably supports a small object near the reflector. The reflector is located about one-half wavelength from the focal point and is concavely curved to a radius of curvature (L) of about one-half the wavelength, to stably support an object one-quarter wavelength (N) from the reflector

Schwannomatosis of the Spinal Accessory Nerve: A Case Report.

Schwannomatosis is a distinct syndrome characterized by multiple peripheral nerve schwannomas that can be sporadic or familial in nature. Cases affecting the lower cranial nerves are infrequent. Here, the authors present a rare case of schwannomatosis affecting the left spinal accessory nerve. Upon genetic screening, an in-frame insertion at codon p.R177 of the Sox 10 gene was observed. There were no identifiable alterations in NF1, NF2, LZTR1, and SMARCB1. This case demonstrates a rare clinical presentation of schwannomatosis in addition to a genetic aberration that has not been previously reported in this disease context

A Possible Origin of Dark Energy

We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field $\phi(x)$, either elementary or composite. In the presence of other matter field, the transformation $\phi(x)\to \phi(x) +$ constant can generate a negative pressure, like the cosmological constant. In this picture, our universe can be thought as a very large bag, similar to the much smaller MIT bag model for a single nucleon.Comment: 4 pages, no figure, typos correcte

Unified description of pairing, trionic and quarteting states for one-dimensional SU(4) attractive fermions

Paired states, trions and quarteting states in one-dimensional SU(4) attractive fermions are investigated via exact Bethe ansatz calculations. In particular, quantum phase transitions are identified and calculated from the quarteting phase into normal Fermi liquid, trionic states and spin-2 paired states which belong to the universality class of linear field-dependent magnetization in the vicinity of critical points. Moreover, unified exact results for the ground state energy, chemical potentials and complete phase diagrams for isospin $S=1/2, 1, 3/2$ attractive fermions with external fields are presented. Also identified are the magnetization plateaux of $m^z=M_s/3$ and $m^z=2M_s/3$, where $M_s$ is the magnetization saturation value. The universality of finite-size corrections and collective dispersion relations provides a further test ground for low energy effective field theory.Comment: 13 pages, 4 figure

Gender differences in health-related quality of life following total laryngectomy

Background: The impact of a total laryngectomy on an individual's life has primarily been measured from a male viewpoint reflecting the demographics of a diagnosis of laryngeal cancer. A small number of studies have looked specifically at females, but very few are comparison studies. Consequently, there is little consistent research regarding any potential gender differences. Aims: To investigate whether there are gender differences in perceptions of health-related quality of life and functional abilities following total laryngectomy. Methods & Procedures: A total of 43 participants (22 males, 21 females), who had undergone a total laryngectomy procedure at least one year previously, took part in the study. They completed The European Organisation for Research and Treatment of Cancer Core Questionnaire Version 3.0 (EORTC QLQ-C30) in conjunction with the disease-specific Head & Neck Cancer Module (QLQ-H&N35). Outcomes & Results: There were no significant differences between males and females on demographic and disease-related variables, except for the following: significantly more females lived alone and changed their employment status following surgery. Males had a significantly higher global health status/quality of life than females (p < 0.05) and significantly higher levels of physical (p = 0.01), emotional (p < 0.01), cognitive (p < 0.05) and social functioning (p < 0.05). After adjusting for differences in living arrangements and change in employment status, differences in emotional and social functioning remained significant. There was a general trend for females to have higher symptom/impairment levels and to report more treatment-related problems, but the majority of these differences were not significant. Conclusions & Implications: Following total laryngectomy, females appear to be worsely affected in aspects of quality of life than males. Emotional and social functioning are particularly vulnerable. The findings imply that rehabilitation programmes after total laryngectomy need to evaluate quality of life and address these specific areas in order to improve patient-reported long-term outcomes

Local Spin Susceptibility of the S=1/2 Kagome Lattice in ZnCu3(OD)6Cl2

We report single-crystal 2-D NMR investigation of the nearly ideal spin S=1/2 kagome lattice ZnCu3(OD)6Cl2. We successfully identify 2-D NMR signals originating from the nearest-neighbors of Cu2+ defects occupying Zn sites. From the 2-D Knight shift measurements, we demonstrate that weakly interacting Cu2+ spins at these defects cause the large Curie-Weiss enhancement toward T=0 commonly observed in the bulk susceptibility data. We estimate the intrinsic spin susceptibility of the kagome planes by subtracting defect contributions, and explore several scenarios.Comment: 4 figures; published in PR-B Rapid Communication

The nature of power corrections in large β0\beta_0 approximation

We investigate the nature of power corrections and infrared renormalon singularities in large $\beta_0$ approximation. We argue that the power correction associated with a renormalon pole singularity should appear at O(1), in contrast to the renormalon ambiguity appearing at $O(1/\beta_0)$, and give an explanation why the leading order renormalon singularities are generically poles.Comment: 6 page

Phase Transitions and Pairing Signature in Strongly Attractive Fermi Atomic Gases

We investigate pairing and quantum phase transitions in the one-dimensional two-component Fermi atomic gas in an external field. The phase diagram, critical fields, magnetization and local pairing correlation are obtained analytically via the exact thermodynamic Bethe ansatz solution. At zero temperature, bound pairs of fermions with opposite spin states form a singlet ground state when the external field $H < H_{c1}$. A completely ferromagnetic phase without pairing occurs when the external field $H > H_{c2}$. In the region $H_{c1} < H < H_{c2}$ we observe a mixed phase of matter in which paired and unpaired atoms coexist. The phase diagram is reminiscent of that of type II superconductors. For temperatures below the degenerate temperature and in the absence of an external field, the bound pairs of fermions form hard-core bosons obeying generalized exclusion statistics.Comment: 9 pages, 5 figures, expanded version with additional text, references and figure