485 research outputs found
Rejecting Collective Bargaining Agreements Under Section 1113 of the Bankruptcy Code - Judicial Precision or Economic Reality?
Before a Chapter 11 debtor in possession can reject the collective bargaining agreement, section 1113 of the Bankruptcy Code requires it to bargain with the representative of its employees and then obtain court approval. Because Congress sought to accommodate the interests of both organized labor and the business community, section 1113 contains numerous terms of compromise which ultimately are interpreted by the courts. The authors have reviewed the major litigation, and have suggested trends in the judicial interpretation of section 1113. However, rejection of collective bargaining litigation is counterproductive with respect to Chapter 11 reorganizations. Rather, the authors believe that the debtor and the union should focus on the economical reality of their situation, rather than the strength of their respective legal positions, to reach agreement at the bargaining table and avoid contract rejection litigation
Evidence of a universal and isotropic 2\Delta/kBTC ratio in 122-type iron pnictide superconductors over a wide doping range
We have systematically investigated the doping and the directional dependence
of the gap structure in the 122-type iron pnictide superconductors by point
contact Andreev reflection spectroscopy. The studies were performed on single
crystals of Ba1-xKxFe2As2 (x = 0.29, 0.49, and 0.77) and SrFe1.74Co0.26As2 with
a sharp tip of Pb or Au pressed along the c-axis or the ab-plane direction. The
conductance spectra obtained on highly transparent contacts clearly show
evidence of a robust superconducting gap. The normalized curves can be well
described by the Blonder-Tinkham-Klapwijk model with a lifetime broadening. The
determined gap value scales very well with the transition temperature, giving
the 2{\Delta}/kBTC value of ~ 3.1. The results suggest the presence of a
universal coupling behavior in this class of iron pnictides over a broad doping
range and independent of the sign of the doping. Moreover, conductance spectra
obtained on c-axis junctions and ab-plane junctions indicate that the observed
gap is isotropic in these superconductors
Superconductivity at 23 K in Pt doped BaFe2As2 single crystals
We report superconductivity in single crystals of the new iron-pnictide
system BaFe1.9Pt0.1As2 grown by a self-flux solution method and characterized
via x-ray, transport, magnetic and thermodynamic measurements. The magnetic
ordering associated with a structural transition at 140 K present in BaFe2As2
is completely suppressed by substitution of 5% Fe with Pt and superconductivity
is induced at a critical temperature Tc=23 K. Full diamagnetic screening in the
magnetic susceptibility and a jump in the specific heat at Tc confirm the bulk
nature of the superconducting phase. All properties of the superconducting
state including transition temperature Tc, the lower critical field Hc1=200 mT,
upper critical field Hc2~65 T, and the slope dHc2/dT are comparable in value to
the those found in other transition-metal-substituted BaFe2As2 series,
indicating the robust nature of superconductivity induced by substitution of
Group VIII elements.Comment: 6 pgs, 4 figs, and 1 tbl, slightly revised, updated reference
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Naming names: Perceptions of name-based HIV reporting, partner notification, and criminalization of non-disclosure among persons living with HIV
Policies of name-based HIV reporting, partner notification (PN), and criminalization of non-disclosure of HIV positive status to sexual partners remain controversial. The views of people living with HIV (PLH) are critical to the success of these three initiatives, but have been understudied. Thus, we interviewed 76 PLH about these policies. Themes arose of potential public health benefits (e.g., epidemiological surveillance and notification of possible exposure) and costs (e.g., deterrence of testing); threats to privacy, civil rights and relationships; government mistrust; and beliefs that prevention is an individual, not governmental responsibility. Misperceptions about the intent, content and scope of these policies, and past experiences of discrimination, shaped these attitudes. To enhance development and implementation of HIV prevention strategies, the views of PLH must be taken into account, and education campaigns need to address misperceptions and mistrust. These data shed light on difficulties in developing and implementing policies that may affect sexual behavior, and have critical implications for future research
Quantum critical scaling at the edge of Fermi liquid stability in a cuprate superconductor
In the high temperature cuprate superconductors, the pervasiveness of
anomalous electronic transport properties suggests that violation of
conventional Fermi liquid behavior is closely tied to superconductivity. In
other classes of unconventional superconductors, atypical transport is well
correlated with proximity to a quantum critical point, but the relative
importance of quantum criticality in the cuprates remains uncertain. Here we
identify quantum critical scaling in the electron-doped cuprate material
La2-xCexCuO4 with a line of quantum critical points that surrounds the
superconducting phase as a function of magnetic field and charge doping. This
zero-temperature phase boundary, which delineates a metallic Fermi liquid
regime from an extended non-Fermi liquid ground state, closely follows the
upper critical field of the overdoped superconducting phase and gives rise to
an expanse of distinct non Fermi liquid behavior at finite temperatures.
Together with signatures of two distinct flavors of quantum fluctuations, this
suggests that quantum criticality plays a significant role in shaping the
anomalous properties of the cuprate phase diagram.Comment: 16 pages, 3 figures + supplementary materia
Josephson effect between electron-doped and hole-doped iron pnictide single crystals
We have observed the Josephson effect in junctions formed between single crystals of SrFe1.74Co0.26As2 and Ba0.23K0.77Fe2As2. The ac Josephson effect was observed under microwave irradiation in the I-V characteristics. By applying an in-plane magnetic field, the critical current is completely modulated and shows a relatively symmetric diffraction pattern consistent with the intermediate junction limit. The observation of the Josephson effect in the p-n bicrystal structure not only has significant implications for designing phase-sensitive junctions to probe the pairing symmetry of iron pnictide superconductors, but also represents an important step in developing all iron pnictide devices for applications.open252
High pressure transport properties of the topological insulator Bi2Se3
We report x-ray diffraction, electrical resistivity, and magnetoresistance
measurements on Bi2Se3 under high pressure and low temperature conditions.
Pressure induces profound changes in both the room temperature value of the
electrical resistivity as well as the temperature dependence of the
resistivity. Initially, pressure drives Bi2Se3 towards increasingly insulating
behavior and then, at higher pressures, the sample appears to enter a fully
metallic state coincident with a change in the crystal structure. Within the
low pressure phase, Bi2Se3 exhibits an unusual field dependence of the
transverse magnetoresistance that is positive at low fields and becomes
negative at higher fields. Our results demonstrate that pressures below 8 GPa
provide a non-chemical means to controllably reduce the bulk conductivity of
Bi2Se3
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It's not just what you say: Relationships of HIV dislosure and risk reduction among MSM in the post-HAART era
In the post-HAART era, critical questions arise as to what factors affect disclosure decisions and how these decisions are associated with factors such as high-risk behaviors and partner variables. We interviewed 1,828 HIV-positive men who have sex with men (MSM), of whom 46% disclosed to all partners. Among men with casual partners, 41.8% disclosed to all of these partners and 21.5% to none. Disclosure was associated with relationship type, perceived partner HIV status and sexual behaviors. Overall, 36.5% of respondents had unprotected anal sex (UAS) with partners of negative/unknown HIV status. Of those with only casual partners, 80.4% had >1 act of UAS and 58% of these did not disclose to all partners. This 58% were more likely to self-identify as gay (versus bisexual), be aware of their status for <5 years and have more partners. Being on HAART, viral load and number of symptoms were not associated with disclosure. This study—the largest conducted to date of disclosure among MSM and one of the few conducted post-HAART—indicates that almost 1/5th reported UAS with casual partners without disclosure, highlighting a public health challenge. Disclosure needs to be addressed in the context of relationship type, partner status and broader risk-reduction strategies
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