12,040 research outputs found
Quantum Loop Subalgebra and Eigenvectors of the Superintegrable Chiral Potts Transfer Matrices
It has been shown in earlier works that for Q=0 and L a multiple of N, the
ground state sector eigenspace of the superintegrable tau_2(t_q) model is
highly degenerate and is generated by a quantum loop algebra L(sl_2).
Furthermore, this loop algebra can be decomposed into r=(N-1)L/N simple sl_2
algebras. For Q not equal 0, we shall show here that the corresponding
eigenspace of tau_2(t_q) is still highly degenerate, but splits into two
spaces, each containing 2^{r-1} independent eigenvectors. The generators for
the sl_2 subalgebras, and also for the quantum loop subalgebra, are given
generalizing those in the Q=0 case. However, the Serre relations for the
generators of the loop subalgebra are only proven for some states, tested on
small systems and conjectured otherwise. Assuming their validity we construct
the eigenvectors of the Q not equal 0 ground state sectors for the transfer
matrix of the superintegrable chiral Potts model.Comment: LaTeX 2E document, using iopart.cls with iopams packages. 28 pages,
uses eufb10 and eurm10 fonts. Typeset twice! Version 2: Details added,
improvements and minor corrections made, erratum to paper 2 included. Version
3: Small paragraph added in introductio
I am not just a nurse: The need for a boundaried ethic of care in the context of prolific relationality
The Ethics of Care (EoC) theory has been widely applied in the field of management, and there is a growing consensus that it is important to recognise the value and practice of care in the workplace. In this paper, we consider the implications of the EoC at work, and in particular the risks unboundaried care demands may pose to employees who encounter unmanageable âcalls to careâ. We present findings from interviews with 27 nurses in Malaysia, which suggest that the demand to care at work, in addition to demands made in the non-work sphere, may be unmanageable. We argue for a more boundaried approach to the EoC at work with a view to ensuring that in valuing care we do not over-burden the carer
Information Content of Equity Analyst Reports
This paper investigates the market reaction to the information released in security analyst reports. It shows that the market reacts significantly and positively to changes in recommendation levels, earnings forecasts, and price targets. While changes in price targets and earnings forecasts both provide information to the market, revisions in price targets have a larger and more significant impact than comparable revisions in earnings forecasts. The text of the report is also a significant source of information as it provides the justifications supporting an analyst's summary opinion. When all of this information is considered simultaneously, some of it, notably the earnings forecasts, is subsumed. The results further show that analysts correctly predict price targets slightly over 50% of the time. Finally, the valuation methodology used does not seem to be correlated with either the market's reaction or the analyst's accuracy.
Saving Shortfalls and Delayed Retirement
Prior research has suggested that many older Americans have not saved enough to maintain consumption levels in old age. One way older persons might respond to inadequate savings would be to extend their worklives by delaying retirement. This paper examines evidence on this matter using the Health and Retirement Study, a nationally representative panel survey of people age 51-61 in 1992 followed for several years in a panel. We use the data to project household retirement assets and to determine how much more saving would be needed to preserve post-retirement consumption levels. Our research then examines the links between derived saving shortfall measures and delayed retirement patterns. Among nonmarried persons, there is evidence that larger shortfalls do produce delayed retirement, though the effect is not quantitatively large. For married couples, pre-retirement wealth shortfalls do not appear to be significantly associated with delayed retirement. Evidently couples have other means of handling saving shortfalls.
Duality and Symmetry in Chiral Potts Model
We discover an Ising-type duality in the general -state chiral Potts
model, which is the Kramers-Wannier duality of planar Ising model when N=2.
This duality relates the spectrum and eigenvectors of one chiral Potts model at
a low temperature (of small ) to those of another chiral Potts model at a
high temperature (of ). The -model and chiral Potts model
on the dual lattice are established alongside the dual chiral Potts models.
With the aid of this duality relation, we exact a precise relationship between
the Onsager-algebra symmetry of a homogeneous superintegrable chiral Potts
model and the -loop-algebra symmetry of its associated
spin- XXZ chain through the identification of their eigenstates.Comment: Latex 34 pages, 2 figures; Typos and misprints in Journal version are
corrected with minor changes in expression of some formula
Critical densities for the Skyrme type effective interactions
We use the stability conditions of the Landau parameters for the symmetric
nuclear matter and pure neutron matter to calculate the critical densities for
the Skyrme type effective nucleon-nucleon interactions. We find that the
critical density can be maximized by adjusting appropriately the values of the
enhancement factor associated with isovector giant dipole resonance,
the quantity which is directly related to the slope of the symmetry energy
and the Landau parameter . However, restricting , and
to vary within acceptable limits reduces the maximum value for the
critical density by . We also show that among the
various quantities characterizing the symmetric nuclear matter,
depends strongly on the isoscalar effective mass and
surface energy coefficient . For realistic values of and we
get to (fm).Comment: 10 pages, 3 figures. Physicsl Review C (in press
Light quark and charm interplay in the Dalitz-plot analysis of hadronic decays in FOCUS
The potentiality of interpreting the D-meson decay-dynamics has revealed
itself to be strongly dependent on our understanding of the light-meson sector.
The statistics collected by FOCUS is already at a level that manifests
parametrization problems for scalar particles. In this paper the first
application of the K-matrix approach in the charm sector is illustrated and
preliminary results on the D+ and Ds decays to three pions are shown.Comment: 9 pages, 7 figures, Invited talk at the Scalar Meson Worksho
Turn-by-Turn Imaging of the Transverse Beam Profile in PEP-II
During injection or instability, the transverse profile of an individual bunch in a storage ring can change significantly in a few turns. However, most synchrotron-light imaging techniques are not designed for this time scale. We have developed a novel diagnostic that enhances the utility of a fast gated camera by adding, inexpensively, some features of a dual-axis streak camera, in order to watch the turn-by-turn evolution of the transverse profile, in both x and y. The beam's elliptical profile is reshaped using cylindrical lenses to form a tall and narrow ellipseâessentially the projection of the full ellipse onto one transverse axis. We do this projection twice, by splitting the beam into two paths at different heights, and rotating the ellipse by 90° on one path. A rapidly rotating mirror scans these vertical âpencilsâ of light horizontally across the photocathode of the camera, which is gated for 3 ns on every Nth ring turn. A single readout of the camera captures 100 images, looking like a stroboscopic photograph of a moving object. We have observed the capture of injected charge into a bunch and the rapid change of beam size at the onset of a fast instability
Modeling Lifetime Earnings Paths: Hypothetical versus Actual Workers
To assess the distributional effects of social security reform proposals, it is essential to have good information on real-world workersâ lifetime earnings trajectories. Until recently, however, policymakers have relied on hypothetical earnings profiles for policy analysis. We use actual lifetime earnings data from the Health and Retirement Study (HRS) to compare actual workersâ covered earnings profiles to these hypothetical profiles. We show that the hypothetical profiles do not track earnings patterns of current retirees; thus lifetime pay levels are much higher than for most HRS workers. Therefore, using hypothetical profiles could misrepresent benefits paid and taxes collected under such reforms.
Recommended from our members
Minimal hepatic toxicity of Onyx-015: spatial restriction of coxsackie-adenoviral receptor in normal liver.
We administered an adenoviral vector, Onyx-015, into the hepatic artery of patients with metastatic colorectal cancer involving the liver. Thirty-five patients enrolled in this multi-institutional phase I/II trial received up to eight arterial infusions of up to 2 x 10(12) viral particles. Hepatic toxicity was the primary dose-limiting toxicity observed in preclinical models. However, nearly 200 infusions of this adenoviral vector were administered directly into the hepatic artery without significant toxicity. Therefore, we undertook this analysis to determine the impact of repeated adenoviral exposure on hepatic function. Seventeen patients were treated at our institution, providing a detailed data set on the changes in hepatic function following repeated exposure to adenovirus. No changes in hepatic function occurred with the first treatment of Onyx-015 among these patients. Transient increases in transaminase levels occurred in one patient starting with the second infusion and transient increases in bilirubin was observed in two patients starting with the fifth treatment. These changes occurred too early to be explained by viral-mediated lysis of hepatocytes. In addition, viremia was observed starting 3-5 days after the viral infusion in half of the patient, but was not associated with hepatic toxicity. To further understand the basis for the minimal hepatic toxicity of adenoviral vectors, we evaluated the replication of adenovirus in primary hepatocytes and tumor cells in culture and the expression of the coxsackie-adenoviral receptor (CAR) in normal liver and colon cancer metastatic to the liver. We found that adenovirus replicates poorly in primary hepatocytes but replicates efficiently in tumors including tumors derived from hepatocytes. In addition, we found that CAR is localized at junctions between hepatocytes and is inaccessible to hepatic blood flow. CAR is not expressed on tumor vasculature but is expressed on tumor cells. Spatial restriction of CAR to the intercellular space in normal liver and diminished replication of adenovirus in hepatocytes may explain the minimal toxicity observed following repeated hepatic artery infusions with Onyx-015
- âŠ