784 research outputs found
A review of San Francisco’s lodging industry: Past performance and future implications
Purpose
The purpose of this paper is to examine the past performance of the San Francisco lodging industry in order to identify future growth potential
Finite Neighborhood Binary Games: a Structural Study
The purpose of this study is to present a systematic analysis of the long-term behavior of the agents of an artificial society under varying payoff functions in finite neighborhood binary games. By assuming the linearity of the payoffs of both cooperating and defecting agents, the type of the game is determined by four fundamental parameters. By fixing the values of three of them and systematically varying the fourth one we can observe a transition from Prisoner\'s Dilemma to Leader Game through Chicken and Benevolent Chicken Games. By using agent-based simulation we are able to observe the long-term behavior of the artificial society with different and gradually changing payoff structure. The difference between different games is explored and the effect of the transition from one game to the other on the society is investigated. The results depend on the personality types of the agents. In this study greedy and Pavlovian agents are considered. In the first case, we observe the most significant change in trajectory structure between Prisoner\'s Dilemma and Chicken Games showing significant difference in the behavioral patterns of the agents. Almost no changes can be observed between Benevolent Chicken and Leader Games, and only small change between Chicken and Benevolent Chicken. The trajectories change from always converging to regularly oscillating patterns with systematically altering amplitude and central values. The results are very similar whether the agents consider themselves as members of their neighborhoods or not. With Pavlovian agents no significant difference can be observed between the four games, the trajectories always converge and the limits smoothly and monotonically depend on the value of the varying parameter.Agent-Based Simulation, N-Person Games, Structure Analysis, Equilibrium
The Complementary Relationship (CR) of Evaporation: A Calibration-Free Diagnostic and Benchmarking Tool for Large-Scale Terrestrial Evapotranspiration Modeling
Calibration-free complementary relationship estimates terrestrial evapotranspiration globally
Initial data transients in binary black hole evolutions
We describe a method for initializing characteristic evolutions of the
Einstein equations using a linearized solution corresponding to purely outgoing
radiation. This allows for a more consistent application of the characteristic
(null cone) techniques for invariantly determining the gravitational radiation
content of numerical simulations. In addition, we are able to identify the {\em
ingoing} radiation contained in the characteristic initial data, as well as in
the initial data of the 3+1 simulation. We find that each component leads to a
small but long lasting (several hundred mass scales) transient in the measured
outgoing gravitational waves.Comment: 18 pages, 4 figure
Nanocomposite-based dual enzyme system for broad-spectrum scavenging of reactive oxygen species
A broad-spectrum reactive oxygen species (ROS)-scavenging hybrid material (CASCADE) was developed by sequential adsorption of heparin (HEP) and poly(L-lysine) (PLL) polyelectrolytes together with superoxide dismutase (SOD) and horseradish peroxidase (HRP) antioxidant enzymes on layered double hydroxide (LDH) nanoclay support. The synthetic conditions were optimized so that CASCADE possessed remarkable structural (no enzyme leakage) and colloidal (excellent resistance against salt-induced aggregation) stability. The obtained composite was active in decomposition of both superoxide radical anions and hydrogen peroxide in biochemical assays revealing that the strong electrostatic interaction with the functionalized support led to high enzyme loadings, nevertheless, it did not interfere with the native enzyme conformation. In vitro tests demonstrated that ROS generated in human cervical adenocarcinoma cells were successfully consumed by the hybrid material. The cellular uptake was not accompanied with any toxicity effects, which makes the developed CASCADE a promising candidate for treatment of oxidative stress-related diseases
Estrogen induces estrogen receptor alpha-dependent cAMP response element-binding protein phosphorylation via mitogen activated protein kinase pathway in basal forebrain cholinergic neurons in vivo
In addition to classical genomic mechanisms, estrogen also exerts
nonclassical effects via a signal transduction system on neurons. To
study whether estrogen has a nonclassical effect on basal forebrain
cholinergic system, we measured the intensity of cAMP response
element-binding protein (CREB) phosphorylation (pCREB) in cholinergic
neurons after administration of 17 beta-estradiol to ovariectomized
(OVX) mice. A significant time-dependent increase in the number of
pCREB-positive cholinergic cells was detected after estrogen
administration in the medial septum-diagonal band (MS-DB) and the
substantia innominata ( SI). The increase was first observed 15 min
after estrogen administration. The role of classical estrogen receptors
(ERs) was evaluated using ER knock-out mice in vivo. The
estrogen-induced CREB phosphorylation in cholinergic neurons was
present in ER beta knock-out mice but completely absent in ER beta
knock-out mice in MS-DB and SI. A series of in vitro studies
demonstrated that estrogen acted directly on cholinergic neurons.
Selective blockade of the mitogen activated protein kinase (MAPK)
pathway in vivo completely prevented estrogen-induced CREB
phosphorylation in cholinergic neurons in MS-DB and SI. In contrast,
blockade of protein kinase A (PKA) was effective only in SI. Finally,
studies in intact female mice revealed levels of CREB phosphorylation
within cholinergic neurons that were similar to those of
estrogen-treated OVX mice. These observations demonstrate an ER
alpha-mediated nonclassical effect of estrogen on the cholinergic
neurons and that these actions are present under physiological
conditions. They also reveal the role of MAPK and PKA-MAPK pathway
activation in nonclassical estrogen signaling in the basal forebrain
cholinergic neurons in vivo
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