15,209 research outputs found
"Does the Appointment of the Outside Director Increase Firm Value? The Evidence from Taiwan"
We examine the stock market reaction to the announcement of outside director appointments in Taiwan. We employ a sample of 58 outside director announcements made by Taiwan Stock Exchange listed firms during the period 1 January, 1999 to 30 June, 2003. Using this data, we can test some important hypotheses regarding the role of outside directors in conjunction with other conditions for corporate performance in affecting the stock market reactions. Our empirical findings indicate that there exists a significantly positive reaction to the announcements. The cumulative abnormal returns ---one indicator of stock market reaction measured by using the methodology of market model based event study --- reached 4.776%. We also find that the abnormal returns are positive and higher with respect to each of the following characteristics: poorer prior corporate performance, the CEO as chairman of the board, larger free cash flow and a higher degree of information asymmetry. Further, we find that the announcement effect is decreasing as number of outside directors increases. Our findings are different from existing literature, for instance, those of Lin, Pope and Young (2003) and Rosenstein and Wyatt (1990) mainly because the outside director appointment is not mandatory in Taiwan. This suggests that the announcement effects could be different across countries. The appointment appears to be more beneficial for a country with poor corporate governance mechanisms.
Nucleon matrix elements and baryon masses in the Dirac orbital model
Using the expansion of the baryon wave function in a series of products of
single quark bispinors (Dirac orbitals), the nonsinglet axial and tensor
charges of a nucleon are calculated. The leading term yields in
good agreement with experiment. Calculation is essentially parameter-free and
depends only on the strong coupling constant value . The importance
of lower Dirac bispinor component, yielding 18% to the wave function
normalization is stressed. As a check, the baryon decuplet masses in the
formalism of this model are also computed using standard values of the string
tension and the strange quark mass ; the results being in a good
agreement with experiment.Comment: 8 pages, 2 tables; LaTeX2
Whitham method for Benjamin-Ono-Burgers equation and dispersive shocks in internal waves in deep fluid
The Whitham modulation equations for the parameters of a periodic solution
are derived using the generalized Lagrangian approach for the case of damped
Benjamin-Ono equation. The structure of the dispersive shock in internal wave
in deep water is considered by this method.Comment: 8 pages, 4 figure
Decoherence and entanglement degradation of a qubit-qutrit system in non-inertial frames
We study the effect of decoherence on a qubit-qutrit system under the
influence of global, local and multilocal decoherence in non-inertial frames.
We show that the entanglement sudden death can be avoided in non-inertial
frames in the presence of amplitude damping, depolarizing and phase damping
channels. However, degradation of entanglement is seen due to Unruh effect. It
is shown that for lower level of decoherence, the depolarizing channel degrades
the entanglement more heavily as compared to the amplitude damping and phase
damping channels. However, for higher values of decoherence parameters,
amplitude damping channel heavily degrades the entanglement of the hybrid
system. Further more, no ESD is seen for any value of Rob's acceleration.Comment: 16 pages, 5 .eps figures, 1 table; Quantum Information Processing,
published online, 5 July, 201
Topological Hall effect and the magnetic states of Nowotney chimney ladder compound CrGe}
We have investigated the magnetic and charge transport properties of single
crystals of Nowotney Chimney Ladder compound CrGe and mapped out
a comprehensive phase diagram reflecting the complicated interplay between the
Dzyaloshinskii-Moriya (DM) interaction, the dipolar interaction, and the
magnetic anisotropy. We have identified a set of interesting magnetic phases
and attributed a finite topological Hall effect to the recently discovered
bi-skyrmion phase. These data also suggest the existence of an anti-skyrmion
state at finite fields for temperatures just below the magnetic ordering
temperature, , as indicated by a distinct change in sign of the
topological Hall effect. Above , we discovered a region of enhanced
magnetic response corresponding to a disordered phase likely existing near the
ferromagnetic critical point under small magnetic fields. Strong spin chirality
fluctuations are demonstrated by the large value of the topological Hall
resistivity persisting up to 1 T which is most likely due to the existence of
the DM interaction. We argue that changes to the topological Hall effect
correspond to different topological spin textures that are controlled by
magnetic dipolar and DM interactions that vary in importance with temperature.Comment: 12 pages, 16 figure
A toy model of fractal glioma development under RF electric field treatment
A toy model for glioma treatment by a radio frequency electric field is
suggested. This low-intensity, intermediate-frequency alternating electric
field is known as the tumor-treating-field (TTF). In the framework of this
model the efficiency of this TTF is estimated, and the interplay between the
TTF and the migration-proliferation dichotomy of cancer cells is considered.
The model is based on a modification of a comb model for cancer cells, where
the migration-proliferation dichotomy becomes naturally apparent. Considering
glioma cancer as a fractal dielectric composite of cancer cells and normal
tissue cells, a new effective mechanism of glioma treatment is suggested in the
form of a giant enhancement of the TTF. This leads to the irreversible
electroporation that may be an effective non-invasive method of treating brain
cancer.Comment: Submitted for publication in European Physical Journal
The theory of optical dispersive shock waves in photorefractive media
The theory of optical dispersive shocks generated in propagation of light
beams through photorefractive media is developed. Full one-dimensional
analytical theory based on the Whitham modulation approach is given for the
simplest case of sharp step-like initial discontinuity in a beam with
one-dimensional strip-like geometry. This approach is confirmed by numerical
simulations which are extended also to beams with cylindrical symmetry. The
theory explains recent experiments where such dispersive shock waves have been
observed.Comment: 26 page
Relativistic Symmetry Suppresses Quark Spin-Orbit Splitting
Experimental data indicate small spin-orbit splittings in hadrons. For
heavy-light mesons we identify a relativistic symmetry that suppresses these
splittings. We suggest an experimental test in electron-positron annihilation.
Furthermore, we argue that the dynamics necessary for this symmetry are
possible in QCD.Comment: 16 pages, LaTeX. Two postscript figures. Final version to be
published in Physical Review Letter
Understanding Pharmaceutical Quality by Design
This review further clarifies the concept of pharmaceutical quality by design (QbD) and describes its objectives. QbD elements include the following: (1) a quality target product profile (QTPP) that identifies the critical quality attributes (CQAs) of the drug product; (2) product design and understanding including identification of critical material attributes (CMAs); (3) process design and understanding including identification of critical process parameters (CPPs), linking CMAs and CPPs to CQAs; (4) a control strategy that includes specifications for the drug substance(s), excipient(s), and drug product as well as controls for each step of the manufacturing process; and (5) process capability and continual improvement. QbD tools and studies include prior knowledge, risk assessment, mechanistic models, design of experiments (DoE) and data analysis, and process analytical technology (PAT). As the pharmaceutical industry moves toward the implementation of pharmaceutical QbD, a common terminology, understanding of concepts and expectations are necessary. This understanding will facilitate better communication between those involved in risk-based drug development and drug application review
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