544 research outputs found
Bylaw Governance
This article argues that Delaware corporate law permits shareholders to use bylaws to circumscribe the managerial authority of the board of directors. While shareholders cannot mandate action by the board, they can enact specific prohibitions on its behavior, so long as the board retains enough discretion to implementâin practice, not merely in theoryâits managerial policies by other means. The use of such circumscribing bylaws to discourage shirking (or analogous managerial abuses) by the directors or officers resembles the use of negative covenants in debt contracts that seek to prevent the debtor from squandering assets. Bylaw governance thus subtly but significantly reallocates governance power within the corporation, so as to reduce the agency costs of management. Its legal validity should also prompt courts and scholars alike to focus less on the quantity of power wielded by the shareholders, and more on the ways that power can be configured to produce managerial efficiencies
The elastic -wave nucleon-pion scattering amplitude and the resonance from lattice QCD
We present the first direct determination of meson-baryon resonance
parameters from a scattering amplitude calculated using lattice QCD. In
particular, we calculate the elastic , -wave nucleon-pion amplitude
on a single ensemble of Wilson-clover fermions with
and . At these quark masses,
the resonance pole is found close to the threshold and a
Breit-Wigner fit to the amplitude gives in agreement with phenomenological determinations.Comment: 7 pages, 2 figures. Agrees with published version, one additional
phase shift point and clarification of different coupling convention
The Peril and Promise of Preferred Stock
Article published in the DeLaw J. Corp. Law
Nuclear envelope starts with a clean sheet
After mitosis, nuclear membranes form directly from ER cisternae before nuclear pore complex reassembly
Tweet valence, volume of abuse, and observersâ dark tetrad personality factors influence victim-blaming and the perceived severity of Twitter cyberabuse
Previous research into Twitter cyberabuse has yielded several findings: victim-blaming (VB) was influenced by victimsâ initial tweet-valence; perceived severity (PS) was influenced independently by tweet valence and abuse volume; VB and PS were predicted by observer narcissism and psychopathy. However, this previous research was limited by its narrow focus on celebrity victims, and lack of consideration of observer sadism. The current study investigated 125 observersâ VB and PS perceptions of lay-user cyberabuse, and influence of observersâ Dark Tetrad scores (psychopathy, narcissism, Machiavellianism, sadism). We manipulated initial-tweet valence (negative, neutral, positive) and received abuse volume (low, high). Our results indicated that VB was highest following negative initial tweets; VB was higher following high-volume abuse. PS did not differ across initial-tweet valences; PS was greater following a high abuse volume. Regression analyses revealed that observer sadism predicted VB across initial-tweet valences; psychopathy predicted PS when initial tweets were âemotiveâ (negative, positive), whereas Machiavellianism predicted PS when they were neutral. Our results show that perceptions of lay-user abuse are influenced interactively by victim-generated content and received abuse volume. Our current results contrast with perceptions of celebrity-abuse, which is mostly determined by victim-generated content. Findings are contextualised within the Warranting Theory of impression formation
Resolved-sideband Raman cooling to the ground state of an optical lattice
We trap neutral Cs atoms in a two-dimensional optical lattice and cool them
close to the zero-point of motion by resolved-sideband Raman cooling. Sideband
cooling occurs via transitions between the vibrational manifolds associated
with a pair of magnetic sublevels and the required Raman coupling is provided
by the lattice potential itself. We obtain mean vibrational excitations
\bar{n}_x \approx \bar{n}_y \approx 0.01, corresponding to a population \sim
98% in the vibrational ground state. Atoms in the ground state of an optical
lattice provide a new system in which to explore quantum state control and
subrecoil laser coolingComment: PDF file, 13 pages including 3 figure
Decoding glutamate receptor activation by the Ca2+ sensor protein hippocalcin in rat hippocampal neurons
Hippocalcin is a Ca2+-binding protein that belongs to a family of neuronal Ca2+sensors and is a key mediator of many cellular functions including synaptic plasticity and learning. However, the molecular mechanisms involved in hippocalcin signalling remain illusive. Here we studied whether glutamate receptor activation induced by locally applied or synaptically released glutamate can be decoded by hippocalcin translocation. Local AMPA receptor activation resulted in fast hippocalcin-YFP translocation to specific sites within a dendritic tree mainly due to AMPA receptor-dependent depolarization and following Ca2+influx via voltage-operated calcium channels. Short local NMDA receptor activation induced fast hippocalcin-YFP translocation in a dendritic shaft at the application site due to direct Ca2+influx via NMDA receptor channels. Intrinsic network bursting produced hippocalcin-YFP translocation to a set of dendritic spines when they were subjected to several successive synaptic vesicle releases during a given burst whereas no translocation to spines was observed in response to a single synaptic vesicle release and to back-propagating action potentials. The translocation to spines required Ca2+influx via synaptic NMDA receptors in which Mg2+ block is relieved by postsynaptic depolarization. This synaptic translocation was restricted to spine heads and even closely (within 1â2 ÎŒm) located spines on the same dendritic branch signalled independently. Thus, we conclude that hippocalcin may differentially decode various spatiotemporal patterns of glutamate receptor activation into site- and time-specific translocation to its targets. Hippocalcin also possesses an ability to produce local signalling at the single synaptic level providing a molecular mechanism for homosynaptic plasticity
Postoperative pain management in children: Guidance from the pain committee of the European Society for Paediatric Anaesthesiology (ESPA Pain Management Ladder Initiative)
The main remit of the European Society for Paediatric Anaesthesiology (ESPA) Pain Committee is to improve the quality of pain management in children. The ESPA Pain Management Ladder is a clinical practice advisory based upon expert consensus to help to ensure a basic standard of perioperative pain management for all children. Further steps are suggested to improve pain management once a basic standard has been achieved. The guidance is grouped by the type of surgical procedure and layered to suggest basic, intermediate, and advanced pain management methods. The committee members are aware that there are marked differences in financial and personal resources in different institutions and countries and also considerable variations in the availability of analgesic drugs across Europe. We recommend that the guidance should be used as a framework to guide best practice
Quantum-state control in optical lattices
We study the means to prepare and coherently manipulate atomic wave packets
in optical lattices, with particular emphasis on alkali atoms in the
far-detuned limit. We derive a general, basis independent expression for the
lattice operator, and show that its off-diagonal elements can be tailored to
couple the vibrational manifolds of separate magnetic sublevels. Using these
couplings one can evolve the state of a trapped atom in a quantum coherent
fashion, and prepare pure quantum states by resolved-sideband Raman cooling. We
explore the use of atoms bound in optical lattices to study quantum tunneling
and the generation of macroscopic superposition states in a double-well
potential. Far-off-resonance optical potentials lend themselves particularly
well to reservoir engineering via well controlled fluctuations in the
potential, making the atom/lattice system attractive for the study of
decoherence and the connection between classical and quantum physics.Comment: 35 pages including 8 figures. To appear in Phys. Rev. A. March 199
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