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The long-lived room-temperature phosphorescence (RTP) originating from thiophene boronate polyvinyl alcohol (PVA) has enabled the creation of metal-ion-responsive RTP films doped with spirolactam ring-containing rhodamine 6G (1). In this study, RTP-active PVA films, namely, TDB@PVA and ATB@PVA, were prepared through boronate esterification of thiophene-2,5-diboronic acid (TDB) and 5-acetylthiophene-2-boronic acid (ATB) with the diol units of PVA. The delayed emission properties were evaluated, revealing an emission band at 477 nm with a turquoise afterglow for TDB@PVA and at 510 nm with a green afterglow for ATB@PVA after UV light irradiation ceased. The photophysical properties were assessed using TD-DFT and DFT calculations at the B3LYP/cc-pVDZ level. N-(rhodamine-6G)lactam dye with a salicylimine unit (1) was doped into the RTP-based PVA films, producing a multicolored afterglow upon the addition of metal ions. This phenomenon is explained by a triplet-tosinglet Förster-type resonance energy transfer process from the cross-linked thiophene boronate in PVA to the metal-ion-activated colored form of 1. This photophysical feature finds applicability in encryption techniques. Notably, the reversible metal-ligand coordination of 1 in the PVA system enabled a write/erase information process. [ABSTRACT FROM AUTHOR]

Natto is a traditional Japanese fermented soy product high in γ-polyglutamic acid (γ-PGA), whose beneficial effects have been reported. We prepared high-γ-PGA natto and compared the dietary influence on liver lipids and cecal microbiota in mice fed a diet containing it or a standard diet. The mice were served a 30% high- γ-PGA natto diet (PGA group) or standard diet (Con group) for 28 days. Liver lipids, fecal lipids, and fecal bile acids were quantified. Cecal microbiota were analyzed by PCR amplification of the V3 and V4 regions of 16S rRNA genes and sequenced using a MiSeq System. Additionally, the cecal short-chain fatty acid profile was assessed. The results revealed that the liver lipid and triglyceride contents were significantly lower (p<0.01) and amounts of bile acids and lipids in the feces were significantly higher in the PGA group than in the Con group. The cecal butyric acid concentration was observed to be significantly higher in the PGA group than in the Con group. Principal component analysis of the cecal microbiota revealed that the PGA and Con groups were distinct. The ratio of FirmicuteslBacteroidetes was found to be significantly low in the PGA mice. The results revealed a significantly higher relative abundance of Lachnospiraceae (p<0.05) and significantly lower relative abundance of Coriobacteriaceae (p<0.01) in the PGA group. Analysis of the correlation between bacterial abundance and liver lipids, cecal short-chain fatty acids, fecal lipids, and fecal bile acids suggested that intestinal microbiota can be categorized into different types based on lipid metabolism. Hepatic lipid accumulation typically facilitates the onset of nonalcoholic fatty liver disease (NAFLD). Our findings suggest that high-γ-PGA natto is a beneficial dietary component for the prevention of NAFLD. [ABSTRACT FROM AUTHOR]

We found that boronate particles (BP), as a selfassembled system prepared by sequential dehydration of benzene-1,4-diboronic acid with pentaerythritol, showed greenish room-temperature phosphorescence (RTP). This emission was observed in both solid and dispersion state in water. To understand the RTP properties, X-ray crystallographic analysis, and density functional theory (DFT) and time-dependent DFT at M06-2X/6-31G(d,p) level were performed using 3,9-dibenzo-2,4,8,10-tetraoxa-3,9-diboraspiro [5.5]undecane (1) as a model compound. Our interest in functionalizing the RTP-active particles led us to graft Rhodamine B onto their surface. The resulting system emitted a dual afterglow via a Förster-type resonance energy transfer process from the BP in the excited triplet state to Rhodamine B acting as an acceptor fluorophore. This emission behavior was used for ratiometric afterglow sensing of water content in THF with a detection limit of 0.28%, indicating that this study could pave the way for a new strategy for developing color-variable afterglow chemosensors for various analytes. [ABSTRACT FROM AUTHOR]

Eight natto-producing factories were surveyed for the contamination of phages that infect Bacillus subtilis (natto). A total of 160 sampling points, including manufacturing pipelines, instruments, floors, drainage ports, containers, and building facilities were inspected by wiping the surfaces. Virulent phages were detected from 28 survey points in four of the factories. Phages were frequently found in factories that had experienced product spoilage by phage contamination within the past 3 years. Isolated phages were not clonal and variations in their genomes were observed, although some phages were very similar. We developed phage-resistant B. subtilis (natto) strains using isolated phages as indicators. They were resistant against all phages found in the survey and those isolated decades ago from spoiled natto. The yueB gene that codes the receptor for phage SPP1 was not essential for the phages tested in this study to infect B. subtilis (natto) strains. [ABSTRACT FROM AUTHOR]

Boronate nanoparticles with built-in tetraphenylethylene (TPE) have been prepared. Their emissive color tuning by altering the amount of rhodamine B grafted onto the surface gave white-light emissive nano-particles. They showed reversible and thermo-responsive emission in the temperature range of 5-65 °C in water, which enabled them to serve as a bright nanothermometer. [ABSTRACT FROM AUTHOR]

Dispersible self-assembled boronate polymers can serve as support materials for metal nanoparticle catalysts. As a proof-of-concept, catalytic systems for the chemoselective hydrogenation of cinnamaldehyde (CA) were prepared by the NaBH4 reduction of PdCl4 2- and AuCl4 - in methanol, in the presence of polyethyleneimine (PEI)-coated boronate particles (BPs) composed of polymeric 3-benzo-2,4,8,10-tetraoxa- 3,9-diboraspiro[5.5]undecane. The Pd-deposited BP (Pd/BP) showed highly selective catalytic activity for the hydrogenation of CA to hydrocinnamaldehyde (HCA) under 0.1 MPa of H2 at 25 °C in environmentally preferable solvents such as water and methanol. Of particular note is the recyclability of the hydrogenation catalyst in methanol; repeated 4 h reactions afforded HCA in >90% selectivity with a reaction conversion of 100%. On another front, when the corresponding Au catalyst (Au/BP) was used in the hydrogenation in water, a favorable selective reduction of CvO to cinnamyl alcohol (CAL) (selectivity ≈ 80%) was obtained with 78% reaction conversion under 0.8 MPa of H2 at 80 °C for 12 h. The potential use of BP-supported metal nanoparticles as green catalysts is discussed. [ABSTRACT FROM AUTHOR]

Novel boron-dibenzopyrromethene dyes with thienyl-cyanoacrylic acid units were synthesized and characterized for application in dye-sensitized solar cells (DSSCs); the dyes feature intense absorption bands in the longer wavelength region with λ[sub max] values of 647 nm (ε = 1.57 x 10[sup 5] M[sup -1] cm[sup -1]) for 1, which has two anchoring units, 660 nm (ε = 1.09 x 10[sup 5] M[sup -1] cm[sup -1]) for regioisomer 2, and 644 nm (ε = 1.39 x 10[sup 5] M[sup -1] cm[sup -1]) for 3, which has a single anchoring unit. Density functional theory (DFT) analysis revealed that these absorption properties are mainly characterized by intramolecular charge transfer from the dibenzopyrromethene core to the thienyl-cyanoacrylic acid unit that depend on both the number of anchoring groups and the position of the thienyl-cyanoacrylic acid unit on the isoindole ring. The relationship between the chemical structures and cell properties of these dyes was investigated. Although the short circuit photocurrent density (J[sub sc]) value of a 1-loaded cell is larger than that of a 3-loaded cell, which reflects the results of the incident photon-to-charge carrier efficiency (IPCE) spectra, the 1-loaded cell has a lower open circuit voltage (V[sub oc]) and fill factor (FF). Accordingly, overall power-to-current conversion efficiencies of 5.24 and 5.48% were obtained for a 1-loaded cell and 3-loaded cell, respectively, under 100 mW cm[sup -2] AM1.5G simulated light. On the other hand, the cell containing butterfly-shaped regioisomer 2, which showed improved intramolecular charge transfer, has an overall power-to-current conversion efficiency of 6.06%; this value is the highest published for BODIPY dyes even though the sensitizer does not contain any strong donor units, such as arylamines. [ABSTRACT FROM AUTHOR]

Presents a model of regional economic development that attempts to explain differences in patterns of economic growth in two regions. Description of the model; Cases that serve to illustrate patterns of economic development; Uneven regional development; Stable regional development; Mixed regional development.

Boron-contained molecular capsules triggered by amines are described for the first time; when Et3N was employed as a chemical stimulus the Lewis acid Et3NH+, produced by solvolysis reaction on the boron, was found to be encapsulated in the internal cavity, whereas use of nBu3N led to the related dynamic capsule capable of accommodating several guest species including Cs+. [ABSTRACT FROM AUTHOR]

Boron-contained molecular capsules triggered by amines are described for the first time; when Et3N was employed as a chemical stimulus the Lewis acid Et3NH+, produced by solvolysis reaction on the boron, was found to be encapsulated in the internal cavity, whereas use of nBu3N led to the related dynamic capsule capable of accommodating several guest species including Cs+. [ABSTRACT FROM AUTHOR]

15-Crown-5-appended metalloporphyrin causes a K+-driven self-organization to bind a bifunctional guest ditopically, thereby allowing the circular dichroism (CD) detection of chirality induced in the ensemble when chiral amines are employed as the guest; the chiroptical properties are discussed. [ABSTRACT FROM AUTHOR]

Describes a monitoring system for distinguishing between the left- and right-handed forms of chiral drugs. Achieving a visual discrimination between enantiomers; Importance of proton transfer and conformational change in a chiral calixarene-based receptor brought about by recognition of a chiral calixarene-based receptor and the subsequent spectral shift in two chromophores; Purpose of synthesizing chromogenic calixarenes;

A self-organized fluorescent sensor consisting of alizarin and o-aminomethylphenylboronic acid 1 is presented, the ensemble shows highly selective fluoride ion-response in H2O-MeOH (1:4 w/w) at pH 5.5. Compound 1 (pK1 = 5.63) at pH 5.5 in the solution follows the equilibrium: alizarin-1 + H+ 1H+ + alizarin. Thus, F- added into the solution preferably binds to 1H+ to allow the ensemble to release alizarin, resulting in a fluorescence quenching. [ABSTRACT FROM AUTHOR]