1,076 research outputs found
Selective hydrogenation of arenes to cyclohexanes in water catalyzed by chitin-supported ruthenium nanoparticles
The selective hydrogenation of arenes to cyclohexanes is promoted by Ru/chitin under aqueous conditions without the loss of C–O/C–N linkages.This work was financially supported by the Ichihara International
Scholarship Foundation (to H. N.), the Institute for
Quantum Chemical Exploration (to H. N.), MEXT (Japan)
through its program “Integrated Research on Chemical Synthesis”
(to H. N.) and the Royal Society through its International
Exchange Scheme (to A. E. H. W. and H. N.). K. B. and
B. R. K. thank the UK EPSRC (EP/J500380/1). Y. M. and A. M.
acknowledge the IGER program at NU. We thank Professors
R. Noyori (NU), S. Saito (NU) and K. Shimizu (Hokkaido U)
for their helpful comments.This is the final version of the article. It first appeared from Royal Society of Chemistry at http://dx.doi.org/10.1039/C6CY00899B
New Perspectives in Sinographic Language Processing Through the Use of Character Structure
Chinese characters have a complex and hierarchical graphical structure
carrying both semantic and phonetic information. We use this structure to
enhance the text model and obtain better results in standard NLP operations.
First of all, to tackle the problem of graphical variation we define
allographic classes of characters. Next, the relation of inclusion of a
subcharacter in a characters, provides us with a directed graph of allographic
classes. We provide this graph with two weights: semanticity (semantic relation
between subcharacter and character) and phoneticity (phonetic relation) and
calculate "most semantic subcharacter paths" for each character. Finally,
adding the information contained in these paths to unigrams we claim to
increase the efficiency of text mining methods. We evaluate our method on a
text classification task on two corpora (Chinese and Japanese) of a total of 18
million characters and get an improvement of 3% on an already high baseline of
89.6% precision, obtained by a linear SVM classifier. Other possible
applications and perspectives of the system are discussed.Comment: 17 pages, 5 figures, presented at CICLing 201
Primary Primitive Neuroectodermal Tumor of the Conus Medullaris in an Elderly Patient: A Case Report and Review of the Literature
Primary spinal primitive neuroectodermal tumors (PNETs) are very rare conditions. Most of these tumors occur in children and young adults. A 63-year-old man with a primary spinal PNET in the conus medullaris from the L1 to L2 level is presented in this report. The optimal treatment of primary spinal PNETs is yet unknown. Surgical resection, radiation therapy, and chemotherapy have been advocated for the treatment of spinal PNET based on PNETs at other sites. However, the outcome is very poor. There are a few reports of cases with long-term survival and no recurrence. In these patients, en bloc resections were performed
Predicting state transitions in the transcriptome and metabolome using a linear dynamical system model
<p>Abstract</p> <p>Background</p> <p>Modelling of time series data should not be an approximation of input data profiles, but rather be able to detect and evaluate dynamical changes in the time series data. Objective criteria that can be used to evaluate dynamical changes in data are therefore important to filter experimental noise and to enable extraction of unexpected, biologically important information.</p> <p>Results</p> <p>Here we demonstrate the effectiveness of a Markov model, named the Linear Dynamical System, to simulate the dynamics of a transcript or metabolite time series, and propose a probabilistic index that enables detection of time-sensitive changes. This method was applied to time series datasets from <it>Bacillus subtilis </it>and <it>Arabidopsis thaliana </it>grown under stress conditions; in the former, only gene expression was studied, whereas in the latter, both gene expression and metabolite accumulation. Our method not only identified well-known changes in gene expression and metabolite accumulation, but also detected novel changes that are likely to be responsible for each stress response condition.</p> <p>Conclusion</p> <p>This general approach can be applied to any time-series data profile from which one wishes to identify elements responsible for state transitions, such as rapid environmental adaptation by an organism.</p
LHR band emissions at mid-latitude and their relationship to ionospheric ELF hiss and relativistic electrons
LHR band emissions observed at mid-latitude were investigated using data from the EXOS-C (Ohzora) satellite. A typical feature of the LHR band emissions is a continuous banded structure without burst-like and cut-off features whose center frequency decreases as the satellite moves to higher latitudes. A statistical analysis of the occurrence characteristics of the phenomena showed that mid-latitude LHR emissions are distributed inside the plasmapause during magnetically quiet periods, and the poleward boundary of the emission region moves to lower latitudes as the magnetic activity increases. The altitude distribution of the waves suggests that the propagation in the LHR duct formed horizontally in the mid-latitude upper-ionosphere. The emission is closely related to the occurrence of ionospheric ELF hiss. It is also shown that LHR emissions are commonly observed in the slot region of the radiation belt, and they sometimes accompany the enhancement of the ionospheric electron temperature. The generation of the LHR band emissions is discussed based on the observed characteristics
Correlated oscillations in Kerr parametric oscillators with tunable effective coupling
We study simultaneous parametric oscillations in a system composed of two
distributed-element-circuit Josephson parametric oscillators in the
single-photon Kerr regime coupled via a static capacitance. The energy of the
system is described by a two-bit Ising Hamiltonian with an effective coupling
whose amplitude and sign depend on the relative phase between parametric pumps.
We demonstrate that the binary phases of the parametric oscillations are
correlated with each other, and that the parity and strength of the correlation
can be controlled by adjusting the pump phase. The observed correlation is
reproduced in our simulation taking pure dephasing into account. The present
result demonstrates the tunability of the Hamiltonian parameters by the phase
of external microwave, which can be used in the the Ising machine hardware
composed of the KPO network.Comment: 9 pages, 8 figure
Ferroelectric property of an epitaxial lead zirconate titanate thin film deposited by a hydrothermal method
Deposition of thin films via hydrothermal method has various advantages: low deposition temperature, high purity, deposition on a three-dimensional structure, and a large thickness. Although an epitaxial lead zirconate titanate (PZT) thin-film deposition has been reported, the ferroelectric measurement has not been conducted due to the peel-off morphology of the film. The current paper investigates the improvement of an epitaxial PZT thin film deposited via a hydrothermal method. By adjusting the position at which the substrate was suspended in the solution, smooth morphology surface was successfully obtained. As a bottom electrode, a 200-nm SrRuO3 thin film was deposited on SrTiO3 single crystals, and the PZT thin film was deposited on SrRuO3. The remanent polarization 2Pr and coercive electric field for PZT on SrRuO3/SrTiO3 (001) were 17.1 muC/cm(2) and 36 kV/cm, respectively, and those of PZT on SrRuO3/SrTiO3 (111) were 32.7 muC/cm(2) and 59 kV/cm, respectively. The reason for large imprint electrical field, 91 kV/cm and 40 kV/cm for each film, was unclear at this stage, although it is associated with self-alignment poling direction. This self-alignment poling direction was confirmed via scanning nonlinear dielectric microscopy and is thought to have been related to the deposition mechanisms
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