Energy-level quantization in YBa2Cu3O7-x phase-slip nanowires

Significant progress has been made in the development of superconducting quantum circuits, however new quantum devices that have longer decoherence times at higher temperatures are urgently required for quantum technologies. Superconducting nanowires with quantum phase slips are promising candidates for use in novel devices that operate on quantum principles. Here, we demonstrate ultra-thin YBa2Cu3O7-x nanowires with phase-slip dynamics and study their switching-current statistics at temperatures below 20 K. We apply theoretical models that were developed for Josephson junctions and show that our results provide strong evidence for energy-level quantization in the nanowires. The crossover temperature to the quantum regime is 12-13 K, while the lifetime in the excited state exceeds 20 ms at 5.4 K. Both values are at least one order of magnitude higher than those in conventional Josephson junctions based on low-temperature superconductors. We also show how the absorption of a single photon changes the phase-slip and quantum state of a nanowire, which is important for the development of single-photon detectors with high operating temperature and superior temporal resolution. Our findings pave the way for a new class of superconducting nanowire devices for quantum sensing and computing

Management Repercussions Of The Increased Tax On Americans Working Overseas

The Tax Increase Prevention and Reconciliation Act of 2005 extended expiring tax-reduction provisions, and created new ones.  However, not all of TIPRA’s provisions reduce taxes.  Many Americans working abroad ended up paying higher income taxes, retroactive to the beginning of 2006.  This created new managerial challenges for companies that have hired Americans in overseas positions, companies that have previously attempted to accommodate the additional costs these workers incur, and raises serious tax policy questions

Untangling The Carried Interest Controversy

Carried interest is a form of deferred compensation payable to managers of hedge funds organized as investment partnerships. There are two tax components of this compensation that are favorable to the manager. First, income taxes are due only when amounts are received rather than when this interest is granted, and second, this income is eligible for the lower tax rates of capital gains and dividends. Special tax treatment has been criticized by some as being an unfair benefit for income that is essentially compensation for services, while proponents of continuing this special treatment point out policy reasons for continuing it, emphasizing characteristics of carried interest that warrant treatment such special treatment. Legislative changes have been proposed but not enacted into law, and there are different alternatives that warrant consideration for the future

Section 409A Deferred Compensation Issues for Domestic and International Businesses

Internal Revenue Code (the “Code”) §409A creates special rules for nonqualified deferred compensation plans, including discounted stock options, severance arrangement, and even some expense reimbursement arrangements.  The primary themes of Section 409A are restrictions that it places upon operation of the deferred compensation plan.  In general, it places restrictions on the elections necessary to defer compensation, restrictions on the funding of the plan, and restrictions on the distributions from the plan.   If the requirements of Code §409A and its regulations are not met, all amounts that had been excluded from gross income under the deferred compensation plan are currently included in gross income.  Additionally. there is interest due from the original deferral that is one percentage point higher than the regular rate of interest for underpayments, plus a crushing additional 20 percent penalty.[1] Accordingly it is of paramount importance to understand how these rules apply, and how to avoid the severe penalties. [1] Code §409A(a)

Apatite - Cholesterol Agglomerates in Human Atherosclerotic Lesions

The purpose of this study was to examine the ultrastructural relationships of cholesterol crystals and apatite deposits in human atherosclerotic lesions. Segments of human aortic atherosclerotic lesions were obtained at autopsy , fixed in glutaraldehyde and dehydrated without using any organic solvents. The aortic segments were coated with carbon and subjected to various scanning electron microscope analyses. These included secondary electron imaging, back scattering of primary electrons, energy dispersive X-ray analysis of selected spots followed by area mapping of calcium and phosphorus , and cathodoluminescence. The information gathered from scanning of selected areas in the lesions by all the techniques showed that cholesterol crystals and apatite deposits are close to each other, within 10 μm distance or less. Cholesterol crystals are often surrounded by or adjacent to apatite. The results indicate that cholesterol and apatite crystals form closely linked agglomerates in human atherosclerotic lesions. Further studies are needed to determine whether precipitation of calcium and cholesterol are somehow linked during atherosclerotic lesion development

Methicillin-resistant Staphylococcus aureus Colonization in Veterinary Personnel

TOC Summary: Prevalence of colonization was 6.5%, and employment within a large-animal practice was a significant risk factor

Metal-Insulator Transitions in Degenerate Hubbard Models and Ax_xC60_{60}

Mott-Hubbard metal-insulator transitions in $N$-fold degenerate Hubbard models are studied within the Gutzwiller approximation. For any rational filling with $x$ (integer) electrons per site it is found that metal-insulator transition occurs at a critical correlation energy $U_c(N,x)=U_c(N,2N-x)=\gamma(N,x)|\bar{\epsilon}(N,x)|$, where $\bar{\epsilon}$ is the band energy per particle for the uncorrelated Fermi-liquid state and $\gamma(N,x)$ is a geometric factor which increases linearly with $x$. We propose that the alkali metal doped fullerides $A_xC_{60}$ can be described by a 3-fold degenerate Hubbard model. Using the current estimate of band width and correlation energy this implies that most of ${\rm A_xC_{60}}$, at integer $x$, are Mott-Hubbard insulators and ${\rm A_3C_{60}}$ is a strongly correlated metal.Comment: 10 pages, Revte