643 research outputs found
Nonadiabatic simulations of photoisomerization and dissociation in ethylene using ab initio classical trajectories
We simulate the nonadiabatic dynamics of photo-induced isomerization and
dissociation in ethylene using ab initio classical trajectories in an extended
phase space of nuclear and electronic variables. This is achieved by employing
the Linearized Semiclassical Initial Value Representation (LSC-IVR) method for
nonadiabatic dynamics where discrete electronic states are mapped to continuous
classical variables using either the Meyer-Miller Stock-Thoss representation or
a more recently introduced spin mapping approach. Trajectory initial conditions
are sampled by constraining electronic state variables to a single initial
excited state, and by drawing nuclear phase space configurations from a Wigner
distribution at finite temperature. An ensemble of classical ab initio
trajectories are then generated to compute thermal population correlation
functions and to analyze the mechanisms of isomerization and dissociation. Our
results serve as a demonstration that this parameter-free semiclassical
approach is computationally efficient and accurate, identifying mechanistic
pathways in agreement with previous theoretical studies, and also uncovering
dissociation pathways observed experimentally.Comment: 8 pages, 5 figure
Simple Portfolio Strategies Utilizing Inflation Factor in Japanese Equity Market
AbstractThis research proposes asset pricing models with inflation factor and also empirically examines performance of the portfolio strategies using the model in the Japanese equity market for the deflationary period covering from 2001 to 2010. Our asset pricing models are Inflation-CAPM and Inflation-FF3 incorporating the inflation factor in the famous CAPM or the Fama-French 3factor model (FF3), respectively. Empirical result for the Inflation-CAPM portfolio strategy reports that the performance (opportunity of the portfolio strategy, accumulated return, rate of wining, average quarterly return and Sharpe ratio) of our strategy is superior to the usual alpha stragegy (CAPM portfolio strategy)
Robust control of multi-jointed arm with a decentralized autonomous control mechanism
A decentralized autonomous control mechanism applied to the control of three dimensional manipulators and its robustness to partial damage was assessed by computer simulation. Decentralized control structures are believed to be quite robust to time delay between the operator and the target system. A 10-jointed manipulator based on our control mechanism was able to continue its positioning task in three-dimensional space without revision of the control program, even after some of its joints were damaged. These results suggest that this control mechanism can be effectively applied to space telerobots, which are associated with serious time delay between the operator and the target system, and which cannot be easily repaired after being partially damaged
What Kinds of Volunteers become more motivated by Community Currency?
Local communities in Japan are struggling to increase the number of participants in volunteer activities in order to revitalize local life. To maintain the enthusiasm of active volunteers and entice new volunteers, a new type of reward to increase motivation is needed. Accordingly, community currencies (hereafter, CCs) have been introduced as a reward in an attempt to provide such a source of motivation. In particular, local residents have been expected to participate in volunteer work more frequently in return for receiving CCs; however, there is no evidence yet as to whether CCs arouse their motivation to do volunteer work. In this study, we investigated whether CCs play a role in raising local residents’ motivation to do volunteer work. Our conclusion is that even some people with a no-reward orientation are likely to have their motivation raised by CCs, rather than diminished. This result shows that their perception towards CCs and cash is dramatically different though CCs have the same monetary value as cash
Effects of antioxidants on survival of adult rat hepatocytes under various oxygen tensions in serum-free primary culture.
Effects of antioxidants, such as superoxide dismutase, vitamin C, vitamin E, 4-(0-benzylphenoxy)-N-methylbutylamine hydrochloride (bifemelane), and selenite on survival of adult rat hepatocytes were examined under normoxic and hyperoxic conditions in serum-free primary culture. The tested antioxidants, except for vitamin C, significantly increased the survival rate of hepatocytes under the normoxic condition (under air). Thus, even the normoxic culture condition is hyperoxic for hepatocytes. Elevation of oxygen tension (40% O2) caused severe morphologic degeneration of hepatocytes and remarkable decrease in the survival rate of the cells. Addition of the antioxidants effectively protected hepatocytes from the morphologic degeneration, and significantly improved the survival of the cells under the hyperoxic condition. These findings indicate that the antioxidants can maintain the long-term survival of hepatocytes in serum-free primary culture.</p
LiNi₀.₅Mn₁.₅O₄ Cathode Materials Co-Doped with La³⁺ and S²⁻ for Use in Lithium-Ion Batteries
Spherical LiNi₀.₅Mn₁.₅O₄ particles co-doped with lanthanum (La) and sulfur (S) were synthesized by a facile co-precipitation assisted solid-state annealing method with stable oxysulfide La₂O₂S (x = 0, 0.3, 0.5, 0.7, 1.0, and 1.2 at%) as a dopant. The prepared composite materials exhibited a slight shrinkage of lattice parameters without any impurity phase under x <= 0.7 at%, and the Ni/Mn disordered arrangement in the spinel lattice increased with an increase in the ratio of dopants, as confirmed by X-ray diffraction and Raman spectroscopy. X-ray photoelectron spectroscopy and electrochemical measurements also clearly indicated that the residual Mn³⁺ in the cubic lattice could be effectively eliminated with the use of La₂O₂S dopants. The composite materials showed outstanding rate and cycling performance compared with those of the pristine material. Specifically, the material doped with 0.5 at% La₂O₂S showed a high reversible capacity of 115.9 mAh g⁻¹ at 10 C, and a remarkable cycling performance of 109.2 mAh g⁻¹ even after 200 cycles. All of these extraordinary performances were attributed to the synergistic effects of La and S in the spinel structure, which induce a suitable pathway for lithium ion and a robust architecture during the electrochemical assessment
Electrochemical Performance of Nanorod-like (La, Zr) Co-Doped Li-rich Li₁.₂Ni₀.₂Mn₀.₆O₂ OF ACCESS Cathodes for Use in Lithium-Ion Batteries
A lithium-rich layered structure in lithium-ion batteries (LIBs) has attracted much attention due to its high capacity of over 250 mAhg⁻¹ after activation. This could satisfy the requirements of next-generation energy-storage devices. However, a spinel-like impurity phase that forms from the pristine layered structure during cycling is considered to be harmful to the structure stability and Li⁺ mobility, resulting in undesired electrochemical performance. In this study, nanorod-like Li₁.₂Ni₀.₂Mn₀.₆O₂ with a three-dimensional architecture was synthesized by evaporative-crystallization with as-prepared nano-MnO₂ as a hard template. The structure stability and Li⁺ mobility of the nanorod-like Li₁.₂Ni₀.₂Mn₀.₆O₂ was improved by the addition of an appropriate molar ratios of (La, Zr) co-dopants. This combination exhibited outstanding capacity retention of 80.9% with a stable discharge capacity of 102 mAh g⁻¹ after 300 cycles under a high current density of 1000 mAg⁻¹ (corresponding to S C). This study suggests that the use of a multi-prong strategy that combines morphology control and co-doping should be an effective method for improving the high-rate performance of Li-rich materials
Genetic diversity of group A rotaviruses associated with repeated outbreaks of diarrhea in a farrow-to-finish farm: identification of a porcine rotavirus strain bearing a novel VP7 genotype, G26
Group A rotaviruses (GARs) are one of the most common causes of diarrhea in suckling pigs. Although a number of G and P genotypes have been identified in porcine GARs, few attempts have been made to study the molecular epidemiology of these viruses associated with diarrhea outbreaks within a farm over an extended period of time. Here, we investigated the molecular characteristics of GARs that caused four outbreaks of diarrhea among suckling pigs in a farrow-to-finish farm over the course of a year. G and P genotyping of GARs detected at each outbreak demonstrated genetic diversity in this farm as follows: G9P[23] was detected at the first outbreak, G9P[13]/[22] and G9P[23] at the second, G3P[7] at the third, and G9P[23], G5P[13]/[22], and P[7] combined with an untypeable G genotype at the fourth. Sequence analysis of the detected GARs revealed that such genetic diversity could have resulted not only from the introduction of new GAR strains, but also from gene reassortment between GAR strains within the farm. Further, the GAR strain carrying the untypeable G genotype was shown to be a novel porcine GAR bearing a new G26 genotype, as confirmed by the Rotavirus Classification Working Group
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