1,589 research outputs found
A Lobbying Approach to Evaluating the Sarbanes-Oxley Act of 2002
We evaluate the net benefits of the Sarbanes-Oxley Act (SOX) for shareholders by studying the lobbying behavior of investors and corporate insiders to affect the final implemented rules under the Act. Investors lobbied overwhelmingly in favor of strict implementation of SOX, while corporate insiders and business groups lobbied against strict implementation. We identify the firms most affected by the law as those whose insiders lobbied against strict implementation, and compare their returns to the returns of less affected firms. Cumulative returns during the four and a half months leading up to passage of SOX were approximately 10 percent higher for corporations whose insiders lobbied against one or more of the SOX disclosure-related provisions than for similar non-lobbying firms. Analysis of returns in the post-passage implementation period indicates that investors' positive expectations with regards to the effects of the law were warranted for the enhanced disclosure provisions of SOX.
Basic fibroblast growth factor mediates carotid plaque instability through metalloproteinase-2 and –9 expression
OBJECTIVE(S): We hypothesized that basic fibroblast growth factor (bFGF) may exert a role in carotid plaque instability by regulating the expression of matrix metalloproteinases (MMP). METHODS: Plaques obtained from 40 consecutive patients undergoing carotid endarterectomy were preoperatively classified as soft or hard. Serum bFGF was pre- and postoperatively measured. The release of MMP-2 and MMP-9 in the blood serum, and the activity, production and expression in the carotid specimens was analyzed. Specific anti-bFGF inhibition tests were performed in vitro on human umbilical artery smooth muscle cells (HUASMC) to evaluate the role of bFGF in the activity, production and expression of MMP-2 and -9. RESULTS: Twenty-one (53%) patients had a soft carotid plaque and 19 (48%) a hard plaque. Preoperative bFGF serum levels were higher in patients with soft plaques [soft=34 (28-39) pg/mL and hard=20 (17-22) pg/mL-p<0.001] and postoperatively returned to normal values (when compared to 10 healthy volunteers). The serum levels of MMP-2 in patients' with soft plaques were higher than those in patients' with hard plaques [soft=1222 (1190-1252) ng/mL and hard=748 (656-793)ng/mL-p<0.0001]. MMP-9 serum values were 26 (22-29) ng/mL for soft plaques and 18 (15-21) ng/mL for hard plaques (p<0.0001). We found increased activity, production and expression of MMP-2 and -9 in soft plaques compared to hard plaques (p<0.001). In vitro inhibition tests on HUASMC showed the direct influence of bFGF on the activity, production and expression of MMP-2 and -9 (p<0.001). CONCLUSIONS: bFGF seems to exert a key role in carotid plaque instability regulating the activity, production and expression of MMP thus altering the physiologic homeostasis of the carotid plaque
Optical pulse propagation in a switched-on photonic lattice: Rabi effect with the roles of light and matter interchanged
A light pulse propagating in a suddenly switched on photonic lattice, when
the central frequency lies in the photonic band gap, is an analog of the Rabi
model where the two-level system is the two resonant (i.e. Bragg-coupled)
Fourier modes of the pulse, while the photonic lattice serves as a
monochromatic external field. A simple theory of these Rabi oscillations is
given and confirmed by the numerical solution of the corresponding Maxwell
equations. This is a direct, i.e. temporal, analog of the Rabi effect,
additionally to the spatial analog in optical beam propagation described in
Opt. Lett. 32, 1920 (2007). An additional high-frequency modulation of the Rabi
oscillations reflects the lattice-induced energy transfer between the electric
and magnetic fields of the pulse.Comment: 3 pages, 5 figure
Risk factors for adenocarcinoma in the surgically transposed colon not exposed to the fecal stream. Etiological considerations extrapolated to sporadic colon carcinoma in the general population
The aim of the study was to analyze the clinical characteristics and outcomes of patients with de novo secondary adenocarcinoma arising in the operatively transposed colon not exposed to the fecal stream
Deploy Energy-efficient Technologies in the Restoration of a Traditional Building in the Historical Center of Catania (Italy)☆
Abstract The policy about energy efficiency of buildings, including minimum energy requirements and energy performance certificate (EPC), have to be also applied to existing buildings in the case of energy retrofit. In this paper, the possible strategies that can be used to reduce the energy needs of traditional massive buildings, that are widespread in the old town of the Mediterranean cities, have been investigated. To this aim, this study evaluates the energy consumption of a massive building placed in Catania city, called "La Casa del Portuale", which was recently refurbished with the aim to host two local administrative centers. The energy needs of this building was evaluated through computer simulation both in the heating and cooling period, on a yearly basis. The activities research were developed analyzing different refurbishment solutions suitable to improve the thermal performance of most traditional buildings without adversely affecting their fabric and character. Therefore, the feasibility comparison has been performed between the examined refurbishment solutions. The results of the proposed research, considering the diffusion of this typology of buildings, could be assumed as reference to a significant portion of the traditional real estate
Multi-Satellite Rain Sensing: Design Criteria and Implementation Issues
In this paper, we propose a novel opportunistic multi-satellite sensor system which overcomes the limitations of the conventional single-satellite solutions of the literature. The considerable robustness to the possible unavailability of some satellites, besides being well suited for powerful 2D reconstruction techniques of the rain field, makes it an appealing solution for experimental tests within national and EU-funded research projects
New mechanism for the production of the extremely fast light particles in heavy-ion collisions in the Fermi energy domain
Employing a four-body classical model, various mechanisms responsible for the
production of fast light particles in heavy ion collisions at low and
intermediate energies have been studied. It has been shown that at energies
lower than 50 A MeV, light particles of velocities of more than two times
higher than the projectile velocities are produced due to the acceleration of
the target light-particles by the mean field of the incident nucleus. It has
also been shown that precision experimental reaction research in normal and
inverse kinematics is likely to provide vital information about which mechanism
is dominant in the production of fast light particles.Comment: 4 pages, 3 figures, LaTeX, to be published in Proceedings of VII
International School-Seminar on Heavy Ion Physics, May 27 - June 1, 2002,
Dubna, Russi
Energetic sustainability of the building substitution: the rewards and the facilitations of the Italian Piano Casa
n/
Strong enhancement of extremely energetic proton production in central heavy ion collisions at intermediate energy
The energetic proton emission has been investigated as a function of the
reaction centrality for the system 58Ni + 58Ni at 30A MeV. Extremely energetic
protons (EpNN > 130 MeV) were measured and their multiplicity is found to
increase almost quadratically with the number of participant nucleons thus
indicating the onset of a mechanism beyond one and two-body dynamics.Comment: 5 pages, 2 figures, submitted to Physical Review Letter
Engineering disorder in three-dimensional photonic crystals
We demonstrate the effect of introducing controlled disorder in
self-assembled three-dimensional photonic crystals. Disorders are induced
through controlling the self-assembling process using an electrolyte of
specific concentrations. Structural characterization reveals increase in
disorder with increase in concentrations of the electrolyte. Reflectivity and
transmittance spectra are measured to probe the photonic stop gap at different
levels of disorder. With increase in disorder the stop gap is vanished and that
results in a fully random photonic nanostructure where the diffuse scattered
intensity reaches up to 100%. Our random photonic nanostructure is unique in
which all scatters have the same size and shape. We also observe the resonant
characteristics in the multiple scattering of light.Comment: 13 pages, 3 figure
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