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This paper addresses the geometry distortion of orthoquinone-containing phenacene-type compounds by comparing the structures of phenanthrene-9,10-dione, chrysene-5,6-dione, and picene-13,14-dione. Interestingly, the calculated geometry of chrysene-5,6-dione under the isolated state was drastically different from the experimental one observed by single-crystal X-ray analysis. Theoretical calculations suggested that the molecular geometry of the o -quinone derivatives was sensitive not only to the sterically intramolecular proximity between the carbonyl oxygen and the hydrogen atoms of the benzene rings but also to intermolecular interactions. The twist distortion affects properties such as oscillator strength and 1-electron transitions, for low-lying excited states. [ABSTRACT FROM AUTHOR]

While the number of private electrical facilities is increasing, there are not enough security personnel to perform the security work. In this paper, we propose a random forest model for predicting leakage current alarms in order to improve the efficiency of electrical safety operations. A random forest was created using periodic inspection data, alarm data, and meteorological data as explanatory variables, and generalization performance was evaluated by OOB-based F-measure. In order to obtain the highest performance, a grid search was performed to optimize the hyperparameters. As a result, it was possible to achieve alarm prediction with a certain level of performance. In addition, the optimal hyperparameters were found by grid search, and the F-measure was improved.

The mechanism of the chain-growth polymerization of 2-bromo-5-chloromagnesio-3-hexylthiophene (1) with Ni[(d1,3-bis-(diphenylphosphino)propane]Cl2, in which head-to-tail poly(3-hexylthiophene) (HT-P3HT) with a low polydispersity is obtained. This chain-growth polymerization involves the coupling reaction of (1) with the polymer through the Ni catalyst, which is transferred intramolecularly to the terminal C-Br bond of the elongated molecule, called 'catalyst transfer polycondensation'.

The Suzuki-Miyaura coupling reaction that can be effectively used for the chain-growth polymerization to produce compounds like polyfluorene from an externally added initiator unit is described. The polycondensation is found to proceed in a chain-growth manner from the initiator unit derived from the catalyst.

The synthesis of poly-(p-phenylene) (PPP) is investigated to see whether a monomer containing no heteroatom in the aromatic ring undergoes catalyst-transfer poly-condensation. It is demonstrated that the Ni-catalyzed polycondensation of 1-bromo-4-chloromagnesio-2,5-dihexyloxybenzene proceeds by a chain-growth mechanism to afford PPP with a narrow polydispersity and that the molecular weight of PPP is controlled by the feed ratio of the monomer to the Ni catalyst.

Poly(p-benzamide)s bearing a chiral side chain on the nitrogen atom were synthesized by chain-growth polycondensation methodology. The results of X-ray crystallographic analysis of 4-(methylamino)benzoic acid oligomers substantiated that they have a helical conformation with three monomer units per turn.

The chain-growth polycondensation method for well defined aromatic polyamides has been developed for the synthesis of poly(p-benzamide) with a low polydispersity by the polycondensation of phenyl 4-(4-octyloxybenzylamino)-benzoate followed by deprotection with TFA. The self-assembly of block copolymers and star polymers containing the well-defined poly(p-benzamide) units will be versatile protocol for nanoarchitectures of aromatic polyamides.

A successful chain-growth polycondensation of meta-substituted monomers, 3-(octylamino) benzoic acid esters that yield poly(m-benzamide)s with well-defined molecular weights and low polydispersities is reported. The inductive effect of the nucleophilic site on the reactivity of the electrophilic site at the meta position of the monomer is as applicable to chain-growth polycondensation as is the resonance effect of the para-substituted monomers.

Background: Pseudocowpox virus (PCPV) infects cattle worldwide with zoonotic potential but has not been isolated in Japan. Thus, the epidemiological status of PCPV infection in cattle is undetermined. Results: In May 2016, a cattle in a farm in Yamaguchi Prefecture showed white vesicles and hyperemia in the mucosa under the tongue surface, but not on the teats and coronary cushions. A parapoxvirus was isolated from the oral lesion swab and was genetically characterized based on the full-length sequence of B2L gene encoding viral envelope. Phylogenetic analysis showed that the isolated virus was classified into PCPV. Conclusion: This case indicates its potential spread in Japan. This is the first report of isolation of PCPV in Japan. [ABSTRACT FROM AUTHOR]

ABSTRACT To synthesize ladder-type polyamides by construction of two amide bonds successively, 2,5-diaminoterephthalic acid derivatives bearing anthranilic acid ester and isatoic anhydride moieties were synthesized and their polymerization was investigated. Polymerization of the methyl ester monomer proceeded in the presence of lithium hexamethyldisilazide (LiHMDS) as a base in tetrahydrofuran (THF). However, mass spectroscopic analysis of the product suggested that not only the bis(trimethylsilyl)amide anion of LiHMDS but also the methoxide anion eliminated at the second amide-linkage formation reaction decomposed the isatoic anhydride unit of the growing oligomer by nucleophilic attack to disturb the polymerization. To reduce the nucleophilicity of the eliminated anion, methyl ester of the monomer was changed to phenyl ester and its polymerization was studied. The reaction conditions were optimized, and the best result was obtained when the polymerization was conducted in the presence of 1.0 equivalent of LiHMDS without additives in THF at 50 °C. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017, 55, 2365-2372 [ABSTRACT FROM AUTHOR]

A 74-year-old woman with right-sided palatal swelling was diagnosed with mucosa-associated lymphoid tissue (MALT) lymphoma on palatal biopsy. In patients with pulmonary MALT lymphoma, the most frequent parenchymal findings of chest CT are consolidations (~55%), nodules (~55%) and masses (~50%). [Extracted from the article]

ABSTRACT Isopropyl-substituted tri(ethylene glycol) is used as a chiral side chain of N-substituted poly( p-benzamide) in order to increase the difference of stability between the right- and left-handed helical structures of the polymer. The target polymer is synthesized by the chain-growth condensation polymerization of the corresponding monomer with an initiator using lithium 1,1,1,3,3,3-hexamethyldisilazide as a base. A circular dichroism (CD) study of the polymer reveals that the CD signal is due to an excess of a thermodynamically controlled right-handed helical structure of the polymer, and that the replacement of the methyl group with a bulkier isopropyl group at the side chain of poly( p-benzamide) increases the abundance of right-handed helical structure in chloroform. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015, 53, 1623-1628 [ABSTRACT FROM AUTHOR]

ABSTRACT Application of chain-growth condensation polymerization (CGCP) to obtain well-defined polybenzoxazole (PBO) was examined. CGCP of both phenyl 3-{(2-methoxyethoxy)methoxy (MEM-oxy)}-4-(octylamino)benzoate ( 1b) ( para-substituted monomer) and phenyl 4-MEM-oxy-3-(octylamino)benzoate ( 3b) ( meta-substituted monomer) was examined in the presence of metal disilazide base and phenyl 4-nitro- or methylbenzoate 2 as an initiator. Polymerization of the latter monomer, but not the former, afforded polymer with controlled molecular weight based on the feed ratio of monomer to initiator and with a narrow molecular weight distribution. Accordingly, monomer 3c, in which the octyl group on the amino nitrogen of 3b was replaced with a 4-(octyloxy)benzyl (OOB) group, was polymerized in the presence of lithium 1,1,1,3,3,3-hexamethyldisilazide (LiHMDS), phenyl 4-methylbenzoate ( 2b), and LiCl in THF at 0 °C to yield poly 3c with well-defined molecular weight ( Mn = 4520-9080) and low polydispersity ( Mw/ Mn ≤ 1.11). Treatment of poly 3c with trifluoroacetic acid simultaneously removed the MEM and OOB groups, affording poly( o-hydroxyamide) (poly 4) without scission of the amide linkages. Cyclodehydration of poly 4 proceeded at 350 °C to yield PBO (poly 5), which was insoluble in organic solvents and acids. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 1730-1736 [ABSTRACT FROM AUTHOR]