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Synthesis of Substituted Cyclooctenes through Cross-Coupling Reactions
No full textCross-coupling methods for the introduction of various substituents onto the olefin moiety of cyclooctenes were developed. A range of 1-substituted cis-cyclooctenes were synthesized. These proto-cols unlocked routes to previously inaccessible derivatives, permitting the syntheses of cis-cyclooctenes bearing various functional groups. Moreover, the method was applied to the synthesis of a 1,2-disubstitut-ed trans-cyclooctene for the first time, which proved to be a significantly more active organocatalyst than the previously developed monosubstituted trans-cyclooctene
Kyūdojin (“Former Natives”) as Defined by Japanese Government Agencies, and its Impact on the Ainu : A Case Study of Samote, a Man Born in the Southern Hokkaido Village of Ainumanai
No full textEffect of soil temperature change on soil nitrogen mineralization rate in the Hakkoda mountain range
No full text森林生態系における土壌窒素の形態変化は、生態系の一次生産や養分循環にとって森林生態系における土壌窒素の形態変化は、生態系の一次生産や養分循環にとって重要なプロセスである。本州北部の八甲田山において、標高別の土壌窒素無機化・硝化速度の特性、標高に沿った地温の違いによる速度変化を調べた。標高400～1,400mの範囲で、標高200mおきに計6地点を調査地に設定した。各調査地においてバリード・バッグ法とレジンコア法を用いて標高別の正味窒素無機化・硝化速度を求めた。正味窒素無機化・硝化速度は標高傾度に沿った単調変化を示さなかった。全体として正味アンモニウム態窒素（NH4-N）の生成が正味硝酸態窒素（NO3-N）の生成よりも高い傾向が認められた。また、土壌内で生成したNH4-Nは降雨浸透によって速やかに下層へ溶脱し、それがNO3-N動態や正味窒素無機化速度に影響を及ぼしていることが示唆された。これらの結果と、標高600mおよび1,000mで採取した土壌を用いた現地移動培養実験の結果を組み合わせると、将来の地温上昇によって土壌微生物によるNH4-NやNO3-Nの正味生成速度が上昇することが示唆された
Neutrophil extracellular trap formation and deoxyribonuclease I activity in patients with otitis media with antineutrophil cytoplasmic antibody-associated vasculitis
No full textIntroduction: No previous studies have evaluated the levels of neutrophil extracellular trap (NET) remnants or the importance of deoxyribonuclease (DNase) I activity based on the disease activity of otitis media with antineutrophil cytoplasmic antibody-associated vasculitis (OMAAV). The aim of this study was to explore the formation of NETs in the middle ear of patients with OMAAV during the onset and remission phases of the disease, with a particular focus on the relationships between the quantifiable levels of NET remnants and DNase I activity. Methods: OMAAV patients were eligible for inclusion. Patients with otitis media with effusion (OME) were examined as controls. The levels of cell-free deoxyribonucleic acid (DNA), citrullinated-histone H3 (cit-H3)-DNA complex, and myeloperoxidase (MPO)-DNA complex were quantified using an enzyme-linked immunosorbent assay. DNase I activity was measured using a fluorometric method. Results: The quantifiable levels of cell-free DNA, cit-H3-DNA complex, and MPO-DNA complex in the middle ear lavage of patients with OMAAV at onset were significantly higher than those in patients with OMAAV at remission and in patients with OME. DNase I activity in the patients with OMAAV at onset was significantly lower than those in patients with OMAAV at remission and OME and was negatively correlated with the level of MPO-DNA complex. Conclusions: This study suggests that NET remnants and DNase I activity may be potentially useful biomarkers for the diagnosis and disease activity of OMAAV
Singlet Fission as the Gateway to Triplet Generation in Heavy Atom-Free Organic Molecules
No full textTriplet generations in heavy atom-free organic molecules are primarily revealed to proceed through singlet fissions (SFs) by investigating the contributions of SFs and intersystem crossings to the generation rates. The spin-flip long-range corrected time-dependent density functional theory calculations on 11 organic molecules known for triplet generation under photoirradiation are performed. The correlation between the descriptors for SF and the experimental singlet-to-triplet conversion rates strongly supports the predominance of SF progressions in all these molecules, corroborated by experimental observations of their triplet-triplet annihilations. Based on these findings, we propose updated conditions for SF progression: There is a high-absorption singlet state just above the triplet-triplet excitation of the chromophore dimer, or the singlet (triplet-triplet) excitation itself is responsible for photoabsorption. To the best of our knowledge, all organic molecules known for rapid triplet state generation fulfill these conditions
Solid Solutions of Plastic/Ferroelectric Crystals : Toward Tailor-Made Functional Materials
No full textPlastic crystals that show ferroelectricity are highly promising materials for a wide range of applications. Their inherent remarkable malleability and highly symmetric cubic structures in the plastic crystal phase ensure that their ferroelectricity and related properties are retained in their bulk polycrystals. To develop functional materials based on such plastic/ferroelectric crystals, methods to tune their properties for specific applications are required. Here, we report the preparation of solid solutions of plastic/ferroelectric ionic crystals by mixing crystals with a common anion but different cations, or crystals with a common cation but different anions, which allows a continuous modification of the Curie temperature of the ferroelectric system over a range of 100 K. This adjustment of the Curie temperature allows the flexible tuning of the pyroelectric properties of the solid solutions, including a significant enhancement of room-temperature performance. The solid solutions also exhibit morphotropic phase boundaries in the composition-temperature phase diagrams, which shows an abrupt change in crystal structures with a variation of composition. This study showcases a simple and versatile property-tuning method that can be expected to pave the way for major progress in the development of materials based on plastic/ferroelectric crystals, which will eventually advance to the stage of pursuing tailor-made functional materials with desired properties
Raman optical activity study of deuterated sugars : deuterium labelling as a tool for structural analysis
No full textStructural analyses using Raman optical activity (ROA) spectroscopy conventionally rely on vibrational signals in the fingerprint region ranging from 100 to 1800 cm-1. Use of deuterium labelling to observe ROA signals in the C-D stretching region provides additional information about a local structure of large molecular systems. So far, the potential of C-D stretching ROA signals for structural analysis has rarely been explored. In the present work, we synthesized model deuterated glucose monosaccharides and studied their ROA properties by employing molecular dynamics and density functional theory to interpret the spectra. A good agreement between the simulated and experimental spectra is achieved when the proper conformer ratios are considered. This shows the usefulness of ROA spectroscopy assisted by deuterium labelling for stereochemical and conformational analysis. Experimental and theoretical ROA studies of deuterated glucose derivatives in the C-D stretching region demonstrated the usefulness of ROA signals in this region for stereochemical and conformational analysis
Nucleotide Sequence and Chromosome mapping of 5S Ribosomal DNA from the Dojo Loach, Misgurnus anguillicaudatus
No full textThere are 2 genetically divergent groups in the dojo loach Misgurnus anguillicaudatus: A and B. Although most wild-type diploids reproduce sexually, clonal diploids (clonal loach) reproduce gynogenetically in certain areas. Clonal loaches produce unreduced isogenic eggs by premeiotic endomitosis, and such diploid eggs develop gynogenetically following activation by the sperm of sympatric wild-type diploids. These clonal loaches have presumably arisen from past hybridization events between 2 different ancestors. The genomic differences between these 2 groups have not been completely elucidated. Thus, new genetic and cytogenetic markers are required to distinguish between these 2 groups. Here, we compared the 5S rDNA region to develop markers for the identification of different dojo loach groups. The nontranscribed sequence (NTS) of the 5S rDNA was highly polymorphic and group-specific. NTS sequences were found in clades of 2 different groups in clonal loaches. In contrast, we did not find any group-specific sequences in the coding region of the 5S rRNA gene. Sequences were located near the centromere of the short arm of the largest submetacentric chromosomes in groups A and B and clonal loaches. Thus, the 5S rDNA of the dojo loach is conserved at the chromosomal location. Whereas, the sequences of the NTS regions evolved group-specifically in the dojo loach, with the sequences of both groups being conserved in clonal loaches