Multilingual author matching across different academic databases: a case study on KAKEN,DBLP, and PubMed

Scientometrics - Researchers often use their native languages to present and exchange ideas. To construct an individual author’s complete profile, a list of their English and non-English...     

Development of a mobile magnetic resonance imaging system for outdoor tree measurements

By combining a 0.3 T permanent magnet with flexible rotation and translation mechanism, a probe with a local electromagnetic shielding, several electrical units, a mobile lift, and an electric wagon, a mobile magnetic resonance imaging (MRI) system was developed for outdoor tree measurements. 2D cross-sectional images of normal and diseased branches of a pear tree were acquired for measurements of T(1), T(2), proton density, and apparent diffusion constant (ADC). The ADC map clearly differentiated diseased from normal branches. A whole-day measurement of the ADC map demonstrated that microscopic water flow in the normal branch changed proportionally with solar radiation. Therefore, we have concluded that our mobile MRI system is a powerful tool for studies of plants in outdoor environments.     

Parallel Implementation of the Nonlinear Semi-NMF Based Alternating Optimization Method for Deep Neural Networks

For computing weights of deep neural networks (DNNs), the backpropagation (BP) method has been widely used as a de-facto standard algorithm. Since the BP method is based on a stochastic gradient descent method using derivatives of objective functions, the BP method has some difficulties finding appropriate parameters such as learning rate. As another approach for computing weight matrices, we recently proposed an alternating optimization method using linear and nonlinear semi-nonnegative matrix factorizations (semi-NMFs). In this paper, we propose a parallel implementation of the nonlinear semi-NMF based method. The experimental results show that our nonlinear semi-NMF based method and its parallel implementation have competitive advantages to the conventional DNNs with the BP method.     

Multi-cast key distribution: scalable,dynamic and provably secure construction

In this paper, we propose a two-round dynamic multi-cast key distribution (DMKD) protocol under the star topology with a central authentication server. Users can share a common session key without revealing any information of the session key to the server and can join/leave to/from the group at any time even after establishing the session key. Our protocol is scalable because communication and computation costs of each user are independent from the number of users. Also, our protocol is still secure if either private key or session-specific randomness of a user is exposed. Furthermore, time-based backward secrecy is guaranteed by renewing the session key for every time period even if the session key is exposed. We introduce the first formal security definition for DMKD under the star topology in order to capture such strong exposure resilience and time-based backward secrecy. We prove that our protocol is secure in our security model in the standard model.     

Efficient Oxidative Cleavage of Tetrahydrofuran‐2‐methanols to γ‐Lactones by a 2‐Iodobenzamide Catalyst in Combination with Oxone®

An environmentally friendly oxidative cleavage of tetrahydrofuran‐2‐methanols to the corresponding γ‐lactones using a catalytic amount of 2‐iodo‐N‐isopropylbenzamide has been developed. The reaction of various tetrahydrofuran‐2‐methanols with the catalyst in the presence of Oxone^® (2 KHSO₅⋅KHSO₄⋅K₂SO₄) as a co‐oxidant in DMF at room temperature successfully affords the corresponding lactones in good to high yields, and recovery of the catalyst is readily accomplished using a reductive work‐up. This method is notable because it enables the transformation of tetrahydrofuran‐2‐methanols to γ‐lactones under mild conditions without the use of any toxic heavy metals.

     

Release kinetics of tritium generated in lithium-enriched Li2+xTiO3 by thermal neutron irradiation

Tritium release kinetics for Li_2+xTiO₃, the lithium-enriched Li₂TiO₃, was investigated by isochronal and isothermal annealing experiments. Tritium release by isochronal annealing showed that the dominant release stage was found at around 600 K. An additional release stage at lower temperature side was appeared with increasing excess lithium, which was attributed to the release of tritium trapped in Li₄TiO₄ structure. The dominant release stage was considered to a release of tritium trapped by irradiation defects. Isothermal annealing experiments indicated that tritium releases were controlled by diffusion process. The diffusion coefficient of Li_2.0TiO₃ was one order of magnitude as large as those of Li_2.2TiO₃ and Li_2.4TiO₃, although their activation energies were almost the same. These results showed that rate-determining step was the diffusion process of tritium in Li₂TiO₃ structure for Li_2+xTiO₃ and excess lithium would make diffusion coefficient smaller. Simulation of tritium-TDS spectra for Li_2.0TiO₃ has clarified that the TDS spectrum forLi_2.0TiO₃ can be demonstrated by using Arrhenius diffusion parameters obtained by isothermal annealing experiment in the present study.     

Asymmetric Cross Couplings of Trifluoromethyl Radical to Vinylarenes with N-Hydroxy-oxazinediones and Subsequent Aerobic Oxidative Homocoupling of 2-Naphthols Catalysed by Chiral Vanadyl Complexes

Asymmetric three-component, 1,2-aminoxy-trifluoromethylation of styrenes with N-hydroxy-1,3-benz/naphthoxazine-2,4-diones (i. e., N-OH-(B/Np)OxzOn) catalysed by chiral vanadyl complexes derived from N-salicylidene-L-t-leucinate were explored. Among 14 different solvents and 13 different catalysts screened, the best reaction scenarios were in 2-propanol with 3-(2,5-dimethyl)phenyl-5-bromo (DMP), or 3-t-butyl-5-bromo substituted catalysts that led to the corresponding complementary (R)- and (S)-products with potential biological activities in 45–91% yields and up to 85 and 75% ee, respectively. Further optimisation with the DMP catalyst led to the best combination of 3-halo/3,5-dihalo-styrenes with 6-/7-Br−N−OH-(B/Np)OxzOn as the trapping agents. The corresponding eight different products were isolated in 52–75% yields with ees in a range of 88–93% (R). Based on Density Functional Theory (DFT) calculations with conformational searches, the origin of enantiocontrol and the working mechanism were proposed by resorting to a bidentate-chelation between the amide or carbamate C=O group and N−OH group in the trapping agent to the vanadyl center followed by asymmetric benzylic radical trapping in an S_H2 fashion. Subsequent Fragment Molecular Orbital (FMO)/Pair Interaction Energy Decomposition Analysis (PIEDA) calculations with the DMP catalyst were carried out to rationalize the extent of asymmetric induction. One representative product derived from p-methyl-styrene and NpOxzOn was hydrolyzed in basic MeOH with decarboxylation to unmask its carbamate moiety. The resulting chiral (R)-N-benzoxy-3-hydroxy-2-naphthamide was subjected to aerobic, oxidative homo-coupling catalysed by the DMP catalyst in CCl₄. The corresponding 2,2-binaphthol product was isolated in 90% (brsm) yield with nearly complete diastereo-control at the created (M)-axial chirality, allowing for sequential, bi-functional asymmetric cross-coupling applications.     

Modified flow geometry for higher extraction performance with a liquid–liquid centrifugal contactor with Taylor vortices

Extraction with multiple theoretical stages by a single contactor is possible when a liquid–liquid countercurrent centrifugal contactor with Taylor vortices (TVs) is used. A series of TVs inside the flow region between the coaxial inner rotor and static outer wall can sustain stable concentration gradients, thereby improving the extraction performance. In the TVs, an axial force driving the dispersed organic phase arises from the different specific weights of the organic and aqueous phases. In this study, the geometry of the flow region was modified using (1) different aspect ratios and (2) tapered and (3) eccentric geometries for better extraction performance. The flows were observed experimentally and simulated numerically using the volume-of-fluid method to understand the flow inside the TVs. Changing the geometry greatly affected the size of the TVs, the flow stability, and the emulsification behavior. In continuous-extraction experiments involving zinc ions with bis(2-ethylhexyl)phosphoric acid, the tapered geometry showed the highest number of theoretical stages because of its simultaneous vigorous agitation, stable TV arrangement, and phase separation.     

Xylanase from Marine Filamentous Fungus Pestalotiopsis sp. AN-7 Was Activated with Diluted Salt Solution Like Brackish Water

The genus Pestalotiopsis are endophytic fungi that have recently been identified as cellulolytic system producers. We herein cloned a gene coding for a xylanase belonging to glycoside hydrolase (GH) family 10 (PesXyn10A) from Pestalotiopsis sp. AN-7, which was isolated from the soil of a mangrove forest. This protein was heterologously expressed by Pichia pastoris as a host, and its enzymatic properties were characterized. PesXyn10A was produced as a glycosylated protein and coincident to theoretical molecular weight (35.3 kDa) after deglycosylation by peptide-NfF-glycosidase F. Purified recombinant PesXyn10A exhibited maximal activity at pH 6.0 and 50 °C, and activity was maintained at 90 % at pH 5.0 and temperatures lower than 30 °C for 24 h. The substrate specificity of PesXyn10A was limited and it hydrolyzed glucuronoxylan and arabinoxylan, but not β-glucan. The final hydrolysis products from birchwood xylan were xylose, xylobiose, and 1,2³-α-D-(4-O-methyl-glucuronyl)-1,4-β-D-xylotriose. The addition of metallic salts (NaCl, KCl, MgCl₂, and CaCl₂) activated PesXyn10A for xylan degradation, and maximal activation by these divalent cations was approximately 160 % at a concentration of 5 mM. The thermostability of PesXyn10A significantly increased in the presence of 50 mM NaCl or 5 mM MgCl₂. The present results suggest that the presence of metallic salts at a low concentration, similar to brackish water, exerts positive effects on the enzyme activity and thermal stability of PesXyn10A.     

Predicting quality decay in continuously passaged mesenchymal stem cells by detecting morphological anomalies

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