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Forest soils that have accumulated anthropogenic sulfur (S) as a result of historical air pollution may gradually or suddenly release inorganic sulfate either by desorption of inorganic sulfate or by mineralization of organic S, even after mitigation of previous air pollution. The release of inorganic sulfate from soil to surface water leads directly to watershed acidification. Thus, whether the organic S compounds that have accumulated in soils are resistant to microbial activity, due to formation of organo-mineral complexes, is essential information for management of forest soil ecosystem services. A nationwide air pollution monitoring survey by the Japanese Ministry of the Environment identified acidification of both surface water and soil in the Lake Ijira watershed of central Japan, presumably sourced from the Chukyo Industrial Area which lies upwind of the watershed. We compared the amount of S accumulated in the Ijira soils (Dystrudepts) with that in comparable soils in other watersheds in central Japan that were less affected by industrial air pollution. To determine how much mineral-associated organic S had accumulated in the Ijira soils, we measured pyrophosphate- extractable S. We used high-resolution x-ray fluorescence (HRXRF) spectroscopy with a double-crystal type high energy resolution spectrometer to estimate the oxidation states of both mineral-associated and free organic S. We also measured S isotope compositions to explore S dynamics in the soils. We found that more S had accumulated in the Ijira soils than in the comparable soils from other watersheds in central Japan. Concentrations of total S in the Ijira soils varied among soil horizons, reaching more than 1000 mg S kg−1 in some horizons. Mineral-associated organic S accounted for more than half of the total accumulated S. High-resolution x-ray fluorescence spectrum analyses showed that mineral-associated organic S was retained at both high and low oxidation states. The δ34S values of total S in the deeper horizons tended to be higher than those of the uppermost horizons of the Ijira soils and correlated positively with concentrations of extractable Al and Fe oxides (which characterize pedogenic minerals). Our results suggest that about half of total accumulated S in Ijira soils is stabilized in pedogenic minerals and the remainder comprises free organic S and adsorbed inorganic sulfates. There might have been repetitive mobilization and immobilization of S and the degraded organic S might have greater affinity with pedogenic minerals. Further, the ratio of total C to mineral-associated organic S correlated negatively with concentrations of extractable Al and Fe oxides, suggesting that organic S is more resistant to mineralization than organic C because S is preferentially associated with the pedogenic minerals. Monitoring of the chemical states of S compounds in soils historically exposed to air pollution is recommended to assist in prediction of the fate of the S compounds that have accumulated in them.

To clarify effects of plasmonic electric field intensity and distributions on the internal quantum efficiency (IQE) of plasmon-induced charge separation (PICS), we took advantage of interparticle p...

In order to improve the performance of localized surface plasmon resonance (LSPR) sensors, lattice plasmons of plasmonic nanoparticle (NP) arrays are often used. The lattice plasmon sensors based on coupling between LSPR of each NP and diffraction of the NP array generally have a higher ability to detect local refractive index changes than conventional LSPR sensors based on random NP ensembles. However, the surface selectivity of the lattice plasmon sensors is lower than that of the LSPR sensors because the local electric field of the former extends far from the particle array surface. In this work, we develop a novel plasmonic–diffractive hybrid sensor that can simultaneously determine both local and bulk refractive indices from two output signals, namely, extinction dip and peak, the wavelengths of which are differently dependent on those indices. The hybrid sensor can evaluate the refractive index changes in the immediate vicinity of the sensor surface by canceling the difference in the bulk refractive...

Acoustic sensing is often used for mapping and monitoring aquatic plants in shallow waters. Recently, high-resolution imaging sonar was applied to study a variety of aquatic organisms. This method can provide high-resolution, three-dimensional (3D) acoustic data on the spatial distribution of submerged plants. However, no commercial software packages are available to digitalize the images of submerged plants generated from imaging sonar data, and the high-resolution imaging sonar method has not been standardized because of a lack of empirical data. In this study, we measured the biomass of submerged plants in the north basin of Lake Biwa using high-resolution acoustic imaging sonar and compared the results to directly measured biomass values to validate the utility of high-resolution acoustic imaging sonar as a quantitative method. Biomass was calculated in 10 randomly selected quadrats (1 × 1 m) in Lake Biwa. The analysis of the resulting data indicated a strong correlation between the number of pixels in the digital images of submerged plants and their directly calculated biomass (R2 = 0.91, p

Summary Objective Elucidation of abnormal connections throughout the whole brain is necessary to understand temporal lobe epilepsy (TLE). We examined abnormalities in whole‐brain white matter integrity and their relationship with duration of illness in patients with TLE. Methods The subjects were 15 patients with TLE and 17 healthy controls. Mean duration of illness in the TLE group was 21.6 years. Tract‐based spatial statistics (TBSS) were used for diffusion tensor imaging (DTI) analysis. Four diffusion tensor metrics, that is, fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated and then examined for differences between the TLE and healthy control groups. We also examined for correlations between DTI parameters and duration of illness in the TLE group. Results In the TLE group, compared with the healthy control group, FA was reduced, and MD and RD were increased, not only in the limbic and temporal lobe regions and their directly connecting regions in both hemispheres, but also in remote white matter regions. Duration of illness showed a significant negative correlation with mean whole‐brain FA and a significant positive correlation with both mean whole‐brain MD and RD. Brain regions showing correlation between disease duration and DTI metrics also extended to the limbic area and its connecting regions, and to remote white matter regions. Significance The results of this study suggest that widespread abnormalities in white matter integrity in patients with TLE are associated with long‐term disease.

PCCを用いた過負荷 MIMOシステムを提案する.PCCは繰り返し符号とM個の累積処理を並列連接した符号であり, 符号化率は柔軟である.受信機ではファクターグラフを基に復号器と検出器間で繰り返し情報をやり取りし(joint detection- decoding)推定を行う.復号器側では復号アルゴリズムの SPA(sum-product algorithm)を用い,検出器側では検出アルゴリズムの FG BP-SGA(factor graph belief propagation scalar Gussian appoximation)を用いる．EXIT解析では低符号化率の時に本システムの閾値は過負荷MIMOシステム環境下でのシャノン限界に漸近することを示した., Parallel concatenated coded overloaded MIMO systems are proposed. The parallel concatenated code (PCC) is a repetition code parallel concatenated with M recursive convolutional component codes. The code rate of PCC is flexible. In the receiver, a joint graph-based detection-decoding algorithm is employed, where the detection at each received antenna is the factor graph-based belief propagation with scalar Gaussian approximation (FG BP-SGA) algorithm, and the decoding of PCC is sum-product algorithm. EXIT analysis show that the Eb/N0 thresholds in the low-rate regime are near to Shannon bound over the ergodic overloaded MIMO channel.

Open-cage ketolactam fullerenes undergo regioselective hydroamination with phenylhydrazine to afford adducts with 1:1 and 1:2 stoichiometry. N-methoxyethoxymethyl (MEM) substitution gave only the 1:1 adduct, the structure of which was unequivocally evidenced via 2D INADEQUATE 13C NMR studies on a 13C enriched derivative. N-electron withdrawing substituents such as N-tert-butoxycarbonyl (Boc) and benzyloxycarbonyl (BnOCO) result in double hydroamination, providing the 1:2 adducts bearing 19-membered ring orifices, with concomitant water encapsulation.

Non-capped gold nanoparticles (AuNPs) with a diameter of 9–13 nm were electrochemically deposited on an ITO electrode, and poly(3-hexylthiophene-2,5-diyl) (P3HT) was spin-coated on the AuNP-deposit...

We have reproduced solar wind charge exchange collisions of hydrogen-like O7+ ions with He gas at collision energies of 42 keV in the laboratory and observed the forbidden transition of 1s2 1 S 0 –1s2s 3 S 1 in helium-like O 6 + ions produced by single electron capture. The measured soft X-ray spectrum had a peak at 560 eV which corresponds to the energy of the forbidden 1s2 1 S 0 –1s2s 3 S 1 transition in the O 6 + ion, and a reasonable energy difference between peak positions of the forbidden and resonance lines was found, which ensured that we succeeded in observing the forbidden transition of O 6 + ions. The dominant electron capture level in the collision of O7+ ions with He can be estimated to be a principal quantum number n = 4 by the classical over barrier model and the two-center atomic orbital close coupling method. After the charge exchange, the population of the 1s2s state becomes large due to cascade transitions from the higher excited states, so the long-lived forbidden transition to the 1s2 1 S 0 ground state is one of main features observed in the charge exchange spectra.

The family Staphyleaceae, which was recently reorganized into the two genera Staphylea and Dalrympelea based on molecular phylogenetic analyses, is sister to a clade of Crossosomataceae, Guamatelaceae, and Stachyuraceae in the order Crossosomatales. In contrast to Crossosomataceae and Stachyuraceae, the embryology of Staphyleaceae has been scarcely studied. We carried out a literature survey and examined three additional species of each genus in order to better understand the evolution of the embryological characters in the family. Characters were nearly identical across examined species. Staphyleaceae shared most characters of nucellus, megagametophyte, and integuments with Stachyuraceae with the exception of several embryological characters. The presence of a nucellar cap was found to be informative and supports the close relationship between Staphyleaceae and Stachyuraceae. We also investigated the evolution of variable characters among Crossosomataceae, Stachyuraceae, and Staphyleaceae. Staphyleaceae species share the presence of a single archesporial cell and absence of an aril as symplesiomorphies. The presence of less than five parietal cells in the nucellus is a possible synapomorphy for the genus Staphylea, while presence of vascular bundles in the testa is a possible synapomorphy for Staphyleaceae. Our observations support the identification of the seed coat as mesotestal. Several variant embryological characters within the family are discussed.

We have succeeded in fabricating two-dimensional (2D) arrays of larger gold nanoparticles (AuNPs) (diameters 17, 28, and 48 nm) by Langmuir-Blodgett (LB) method. Although the particle size of AuNPs is one of the most important factors in order to control the optical properties of 2D arrays, there have been reported only the size of less than ∼20 nm. This is a first report on the bottom-up fabrication of 2D arrays consisting of hydrophobic AuNP with the diameter of ∼50 nm, of which the size is expected to obtain maximum near-field effects. Octadecylthiolate-capped AuNPs (ODT-AuNPs) which were prepared by our method could be re-dispersed in chloroform even after drying completely, realizing the spreading of the colloidal chloroform solution onto the water surface. Accordingly, densely-packed 2D LB films of ODT-AuNPs could be fabricated on an indium-tin-oxide substrate, when water as the subphase and polyethylene glycol (PEG) as an amphiphilic agent were used. PEG played an important role to form densely-packed film uniformly due to increasing affinity between hydrophobic AuNP and water. Absorption spectra of the films revealed that the resonance wavelengths of plasmon oscillation through interparticle plasmon coupling were clearly correlated with the particle sizes rather than deposition densities.

Although diffusion tensor imaging (DTI) have revealed brain abnormalities in bipolar disorder (BD) subjects, DTI methods might not detect disease-related abnormalities in the white matter (WM) where nerve fibers are crossing. We investigated BD myelin-related abnormal brain regions in both gray matter and WM for 29 BD and 33 healthy control (HC) participants using T1-weighted (T1w)/T2-weighted (T2w) ratio images that increase myelin-related contrast irrespective of nerve fiber orientation. To check effect of the brain volume, the results were compared with those of voxel-based morphometry (VBM). We found significantly lower T1w/T2w signal intensity in broad WM regions in BD subjects, including the corpus callosum, corona radiata, internal capsule, middle cerebellar peduncle and cerebellum. Regional volume reduction was found in the WM bilateral posterior thalami and retrolenticular part of the internal capsules of BD subjects. We also performed tract-based spatial statistics (TBSS) in 25 BD and 24 HC participants and compared those for the T1w/T2w ratio images. Both methods detected the BD corpus callosum abnormality. Further, the ratio images detected the corona radiata and the cerebellar abnormality in BD. These results suggest that T1w/T2w ratio image analysis could take a complementary role with the DTI method in elucidating myelin-related abnormalities in BD.

The crystal structure of the catalytic domain of a glycoside hydrolase family 6 cellobiohydrolase from the basidiomycete P. chrysosporium was solved in apo and cellobiose-liganded forms at 1.2 and 2.1 Å resolution, respectively., Cellobiohydrolases belonging to glycoside hydrolase family 6 (CBH II, Cel6A) play key roles in the hydrolysis of crystalline cellulose. CBH II from the white-rot fungus Phanerochaete chrysosporium (PcCel6A) consists of a catalytic domain (CD) and a carbohydrate-binding module connected by a linker peptide, like other known fungal cellobiohydrolases. In the present study, the CD of PcCel6A was crystallized without ligands, and p-nitrophenyl β-d-cellotrioside (pNPG3) was soaked into the crystals. The determined structures of the ligand-free and pNPG3-soaked crystals revealed that binding of cellobiose at substrate subsites +1 and +2 induces a conformational change of the N-terminal and C-terminal loops, switching the tunnel-shaped active site from the open to the closed form.

The cover image is based on the Original Research Microstructural abnormalities in callosal fibers and their relationship with cognitive function in schizophrenia: A tract‐specific analysis study by Yuji Ohoshi et al., DOI: 10.1002/brb3.1357. [Image: see text]

Pyrroloquinoline quinone (PQQ) is known as the “third coenzyme” following nicotinamide and flavin. PQQ-dependent enzymes have previously been found only in prokaryotes, and the existence of a eukaryotic PQQ-dependent enzyme was in doubt. In 2014, we found an enzyme in mushrooms that catalyzes the oxidation of various sugars in a PQQ-dependent manner and that was a PQQ-dependent enzyme found in eukaryotes. This paper presents the X-ray crystal structures of this eukaryotic PQQ-dependent quinohemoprotein, which show the active site, and identifies the amino acid residues involved in the binding of the cofactor PQQ. The presented X-ray structures reveal that the AA12 domain is in a binary complex with the coenzyme, clearly proving that PQQ-dependent enzymes exist in eukaryotes as well as prokaryotes. Because no biosynthetic system for PQQ has been reported in eukaryotes, future research on the symbiotic systems is expected., Pyrroloquinoline quinone (PQQ) was discovered as a redox cofactor of prokaryotic glucose dehydrogenases in the 1960s, and subsequent studies have demonstrated its importance not only in bacterial systems but also in higher organisms. We have previously reported a novel eukaryotic quinohemoprotein that exhibited PQQ-dependent catalytic activity in a eukaryote. The enzyme, pyranose dehydrogenase (PDH), from the filamentous fungus Coprinopsis cinerea (CcPDH) of the Basidiomycete division, is composed of a catalytic PQQ-dependent domain classified as a member of the novel auxiliary activity family 12 (AA12), an AA8 cytochrome b domain, and a family 1 carbohydrate-binding module (CBM1), as defined by the Carbohydrate-Active Enzymes (CAZy) database. Here, we present the crystal structures of the AA12 domain in its apo- and holo-forms and the AA8 domain of this enzyme. The crystal structures of the holo-AA12 domain bound to PQQ provide direct evidence that eukaryotes have PQQ-dependent enzymes. The AA12 domain exhibits a six-blade β-propeller fold that is also present in other known PQQ-dependent glucose dehydrogenases in bacteria. A loop structure around the active site and a calcium ion binding site are unique among the known structures of bacterial quinoproteins. The AA8 cytochrome domain has a positively charged area on its molecular surface, which is partly due to the propionate group of the heme interacting with Arg181; this feature differs from the characteristics of cytochrome b in the AA8 domain of the fungal cellobiose dehydrogenase and suggests that this difference may affect the pH dependence of electron transfer. IMPORTANCE Pyrroloquinoline quinone (PQQ) is known as the “third coenzyme” following nicotinamide and flavin. PQQ-dependent enzymes have previously been found only in prokaryotes, and the existence of a eukaryotic PQQ-dependent enzyme was in doubt. In 2014, we found an enzyme in mushrooms that catalyzes the oxidation of various sugars in a PQQ-dependent manner and that was a PQQ-dependent enzyme found in eukaryotes. This paper presents the X-ray crystal structures of this eukaryotic PQQ-dependent quinohemoprotein, which show the active site, and identifies the amino acid residues involved in the binding of the cofactor PQQ. The presented X-ray structures reveal that the AA12 domain is in a binary complex with the coenzyme, clearly proving that PQQ-dependent enzymes exist in eukaryotes as well as prokaryotes. Because no biosynthetic system for PQQ has been reported in eukaryotes, future research on the symbiotic systems is expected.

Introduction The corpus callosum serves the essential role of relaying cognitive information between the homologous regions in the left and the right hemispheres of the brain. Cognitive impairment is a core dysfunction of schizophrenia, but much of its pathophysiology is unknown. The aim of this study was to elucidate the association between microstructural abnormalities of the corpus callosum and cognitive dysfunction in schizophrenia. Methods We examined stepwise multiple regression analysis to investigate the relationship of the fractional anisotropy (FA) of callosal fibers in each segment with z‐scores of each brief assessment of cognition in schizophrenia subtest and cognitive composite score in all subjects (19 patients with schizophrenia [SZ group] and 19 healthy controls [HC group]). Callosal fibers were separated into seven segments based on their cortical projection using tract‐specific analysis of diffusion tensor imaging. Results The FA of callosal fibers in the temporal segment was significantly associated with z‐scores of token motor test, Tower of London test, and the composite score. In the SZ group, the FA of callosal fibers in the temporal segment was significantly associated with the z‐score of the Tower of London test. In addition, the FA of callosal fibers in temporal segment showed significant negative association with the positive and negative syndrome scale negative score in the SZ group. Compared to the HC group, the FA in temporal segment was significantly decreased in the SZ group. Conclusion Our results suggest that microstructural abnormalities in the callosal white matter fibers connecting bilateral temporal lobe cortices contribute to poor executive function and severe negative symptom in patients with schizophrenia.

Identifying nonpoint phosphorus (P) sources in a watershed is essential for addressing cultural eutrophication and for proposing best-management solutions. The oxygen isotope ratio of phosphate (δ1...

Pyrroloquinoline quinone (PQQ) was discovered as a redox cofactor of prokaryotic glucose dehydrogenases in the 1960s, and subsequent studies have demonstrated its importance not only in bacterial systems but also in higher organisms. We have previously reported a novel eukaryotic quinohemoprotein that exhibited PQQ-dependent catalytic activity in a eukaryote. The enzyme, pyranose dehydrogenase (PDH), from the filamentous fungus Coprinopsis cinerea (CcPDH) of the Basidiomycete division, is composed of a catalytic PQQ-dependent domain classified as a member of the novel auxiliary activity family 12 (AA12), an AA8 cytochrome b domain, and a family 1 carbohydrate-binding module (CBM1), as defined by the Carbohydrate-Active Enzymes (CAZy) database. Here, we present the crystal structures of the AA12 domain in its apo- and holo-forms and the AA8 domain of this enzyme. The crystal structures of the holo-AA12 domain bound to PQQ provide direct evidence that eukaryotes have PQQ-dependent enzymes. The AA12 domain exhibits a six-blade β-propeller fold that is also present in other known PQQ-dependent glucose dehydrogenases in bacteria. A loop structure around the active site and a calcium ion binding site are unique among the known structures of bacterial quinoproteins. The AA8 cytochrome domain has a positively charged area on its molecular surface, which is partly due to the propionate group of the heme interacting with Arg181; this feature differs from the characteristics of cytochrome b in the AA8 domain of the fungal cellobiose dehydrogenase and suggests that this difference may affect the pH dependence of electron transfer.IMPORTANCE Pyrroloquinoline quinone (PQQ) is known as the "third coenzyme" following nicotinamide and flavin. PQQ-dependent enzymes have previously been found only in prokaryotes, and the existence of a eukaryotic PQQ-dependent enzyme was in doubt. In 2014, we found an enzyme in mushrooms that catalyzes the oxidation of various sugars in a PQQ-dependent manner and that was a PQQ-dependent enzyme found in eukaryotes. This paper presents the X-ray crystal structures of this eukaryotic PQQ-dependent quinohemoprotein, which show the active site, and identifies the amino acid residues involved in the binding of the cofactor PQQ. The presented X-ray structures reveal that the AA12 domain is in a binary complex with the coenzyme, clearly proving that PQQ-dependent enzymes exist in eukaryotes as well as prokaryotes. Because no biosynthetic system for PQQ has been reported in eukaryotes, future research on the symbiotic systems is expected.

A convenient, one-step, approach for surface modification with hydrophobic thiol or its dye-derivative of hydrophilic citrate-capped Au nanoparticles (Cit–AuNPs) is demonstrated. This method depended on the solubility of both Cit–AuNP and thiol or its derivative in the reaction solvent. We investigated a variety of solvents for Cit–AuNPs with 15–75 nm sizes and a capping molecule, octadecanethiol (ODT) or a disulfide derivative of hydrophobic porphyrin (PC10S)2. As to ODT, surface immobilization of Cit–AuNPs with ODT was successful in 2-propanol, while N,N-dimethylformamide was best in the case of (PC10S)2. In both cases, surface modified AuNPs were redispersible even after storing under dried powder conditions. Two-dimensional monoparticle films of surface-modified AuNPs by the Langmuir–Blodgett method with ethylene glycol as subphase could be formed and exhibit surface-enhanced Raman scattering. Spectra from the porphyrin skeleton were certainly observed, with the maximum photoluminescence enhancement of 15-fold, around 50-nm size. As to AuNP with 17-nm diameter, mixed monolayer assemblies of (PC10S)2 and octanethiol with different concentration ratios were fabricated and spectroscopic enhancement effects due to localized surface plasmon resonance were investigated.

Elevated serum proinflammatory cytokines are associated with the reduction of cytochrome P450 enzyme (CYP) activity. This study aimed to evaluate the oxycodone pharmacokinetics, central symptoms, and serum proinflammatory cytokines based on cachexia stage in cancer patients.Forty-seven cancer patients receiving extended-release oxycodone were enrolled. Predose plasma concentrations of oxycodone and its metabolites were normalized with the daily dose and body weight. The central symptoms and serum level of proinflammatory cytokines were investigated at each cachexia stage.The plasma concentrations of oxycodone in patients with cachexia and refractory cachexia were significantly higher than that in patients with precachexia. The metabolic ratio to noroxycodone in patients with cachexia was significantly lower than that in patients with precachexia. The patients with a higher cachexia stage had a higher serum level of interleukin-6 (IL-6), but not tumor necrosis factor-α and interleukin-1β. The serum IL-6 level was correlated with the plasma concentration of oxycodone and inversely with the metabolic ratio to noroxycodone. The incidence of somnolence was not associated with the plasma oxycodone concentration. In contrast, the cachexia stage and its associated serum IL-6 level were correlated with the incidence of somnolence.Cancer cachexia raised the plasma exposure of oxycodone through the reduction of CYP3A metabolic pathway. The reduction of CYP3A in cachectic cancer patients was associated with an elevation of serum IL-6. Although cachectic cancer patients with higher serum IL-6 levels had the symptom of somnolence, the alterations in oxycodone pharmacokinetics were not related to the incidence of symptom.

A pyranose dehydrogenase from Coprinopsis cinerea (CcPDH) is an extracellular quinohemoeprotein, which consists a b-type cytochrome domain, a pyrroloquinoline-quinone (PQQ) domain, and a family 1-type carbohydrate-binding module. The electron transfer reaction of CcPDH was studied using some electron acceptors and a carbon electrode at various pH levels. Phenazine methosulfate (PMS) reacted directly at the PQQ domain, whereas cytochrome c (cyt c) reacted via the cytochrome domain of intact CcPDH. Thus, electrons are transferred from reduced PQQ in the catalytic domain of CcPDH to heme b in the N-terminal cytochrome domain, which acts as a built-in mediator and transfers electron to a heterogenous electron transfer protein. The optimal pH values of the PMS reduction (pH 6.5) and the cyt c reduction (pH 8.5) differ. The catalytic currents for the oxidation of l-fucose were observed within a range of pH 4.5 to 11. Bioelectrocatalysis of CcPDH based on direct electron transfer demonstrated that the pH profile of the biocatalytic current was similar to the reduction activity of cyt c characters.

Pulse radiolysis of highly concentrated poly(4-hydroxystyrene) (PHS) solutions in cyclohexanone and p -dioxane was performed both with and without an onium-type photoacid generator (PAG). With increasing PHS concentration, the rate constant of deprotonation of PHS radical cations was found to decrease. In the presence of PAG, the yield of the multimer radical cation of PHS was shown to decrease. We found that pairing between the anions produced by the attachment of dissociative electrons of PAGs and the monomer PHS radical cations restrict local molecular motions, leading to the formation of the multimer PHS radical cations.

Thermal and chemical stabilities of silver nanoplates (AgPLs), which are triangle plate-shaped silver nanoparticles, were improved by coating with titanium oxide. The titanium oxide layer prepared by a dip-coating method was certainly advantageous for the improvement of thermal stability. Furthermore, the overlayering of titanium oxide by a spray pyrolysis method was quite useful for improving the chemical stability against I(-) exposure. Such a coating exhibited satisfactory refractive index sensitivities.

Wood density and wood chemical traits are strong predictors of tree performance, carbon stock, and wood decomposition, which play important roles in ecosystem processes and carbon and nutrient cycling in forests. However, it remains unknown how root wood traits are related to stem wood traits. We examined the relationships of wood density and wood chemical traits (lignin and nitrogen concentrations, carbon-to-nitrogen ratio) between the stems and coarse roots of 90 individuals representing 53 tropical tree species in Malaysian Borneo. We developed regression equations of each wood trait using the standardized major axis method. Each root wood trait was highly correlated with the corresponding stem wood trait, and most regression equations fitted well (R2 > 0.5). The lignin concentration of roots was significantly greater than that of stems. We conclude that root wood traits can be estimated from the corresponding stem wood traits in South-East Asian tropical trees. Further analysis of coarse root decomposability will provide more accurate estimates of carbon and nutrient fluxes in tropical forest ecosystems.

This study aimed to evaluate plasma 4β-hydroxycholesterol as an endogenous marker of CYP3A4/5 activity in early postpartum women and its impact on the plasma disposition of amlodipine. Twenty-seven early postpartum women treated with amlodipine for pregnancy-induced hypertension were enrolled. The plasma concentration of 4β-hydroxycholesterol and its ratio to cholesterol in postpartum and in non-perinatal women were evaluated. The predose plasma concentration of amlodipine was determined at steady state. The medians of the plasma 4β-hydroxycholesterol concentration at day 0-3 and 8-21 after delivery were 146 and 161 ng/mL, respectively. No significant difference was observed in the plasma concentration of 4β-hydroxycholesterol between the postpartum periods. The plasma concentration of 4β-hydroxycholesterol and its ratio to cholesterol in postpartum women were significantly higher than those in non-perinatal women. A large individual variability was observed in the dose-normalized plasma concentration of amlodipine in early postpartum women. A weak negative correlation was observed between the dose-normalized plasma concentration of amlodipine and the plasma concentration of 4β-hydroxycholesterol. In conclusion, early postpartum women possessed higher CYP3A activity based on plasma 4β-hydroxycholesterol and had a large pharmacokinetic variability in amlodipine. CYP3A activity during the early postpartum period had an effect on the plasma disposition of amlodipine.

Plasmon-induced charge separation (PICS)1,2 involves electron transfer from plasmonic noble metal nanoparticles or compound nanoparticles to an n-type semiconductor such as TiO2. Oxidation reactions involved in PICS are based on a charge accumulation mechanism (Figure a) or a hole ejection mechanism (Figure b).3 The latter enables nanoscale local oxidation at relatively positive potentials.4-7 This can be applied to photoinduced nanofabrication beyond the diffraction limit of light. For instance, chiral plasmonic nanostructures can be prepared by PICS under right or left circularly polarized light (Figure c).8,9 Some other applications of the plasmonic hole ejection will also be mentioned. Enhancement of PICS with hole ejection through plasmon coupling10 and its application to photocatalysis will also be described. References Y. Tian and T. Tatsuma, J. Am. Chem. Soc., 127, 7632 (2005). T. Tatsuma, H. Nishi, and T. Ishida, Chem. Sci., 8, 3325 (2017) [review]. T. Tatsuma and H. Nishi, Nanoscale Horiz., 5, 597-606 (2020) [review]. E. Kazuma, N. Sakai, and T. Tatsuma, Chem. Commun., 47, 5777 (2011). I. Tanabe and T. Tatsuma, Nano Lett., 12, 5418 (2012). K. Saito, I. Tanabe, and T. Tatsuma, J. Phys. Chem. Lett., 7, 4363 (2016). H. Nishi, M. Sakamoto, and T. Tatsuma, Chem. Commun., 54, 11741 (2018). K. Saito and T. Tatsuma, Nano Lett., 18, 3209 (2018). K. Morisawa, T. Ishida, and T. Tatsuma, ACS Nano, 14, 3603 (2020). T. Ishida and T. Tatsuma, J. Phys. Chem. C, 122, 26153 (2018). Figure 1

CAZypedia was initiated in 2007 to create a comprehensive, living encyclopedia of the carbohydrate-active enzymes (CAZymes) and associated carbohydrate-binding modules involved in the synthesis, modification, and degradation of complex carbohydrates. CAZypedia is closely connected with the actively-curated CAZy database, which provides a sequence-based foundation for the biochemical, mechanistic, and structural characterization of these diverse proteins. Now celebrating its 10th anniversary online, CAZypedia is a successful example of dynamic, community-driven, and expert-based biocuration. CAZypedia is an open-access resource available at URL http://www.cazypedia.org.

Biologically formed amorphous silica (biosilica) is widely found in diatoms, marine sponges, terrestrial plants, and bacteria, some of which have been well characterized. Although rice plants produce large amounts of biosilica (plant opal) in their leaf blades and rice husks, the molecular mechanism of biomineralization is still poorly understood. In the present study, we investigated the fundamental properties of plant opal in leaf blades of the rice plants (Oryza sativa) by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy. The number of fan-shaped plant opal increases in the motor cells (bubble-shaped epidermal cells) during heading time. High-resolution SEM analysis revealed that the plant opals are composed of nanoparticles, as is the case with diatom silica and siliceous spicule of sponge. Organic matrices in biominerals have been considered to control mineralization. Biosilicas in diatom and marine sponge are formed under ambient conditions using organic matrices, unique proteins, and long-chain polyamines. In this study, we report the establishment of purification method of plant opals from rice leaf blades. Finally, we succeeded in extracting organic matrices from the purified plant opal.

Quantification of sulfur (S) deposition is critical to deciphering the environmental archive of S in terrestrial ecosystems. Here we propose a mixing model that quantifies S deposition based on the S isotope ratio (δS) in tree rings. We collected samples from Japanese cedar ( D. Don) stumps from two sites: one near Yokkaichi City (YOK), which is well known for having the heaviest S air pollution in the world, and one at Inabu-cho (INA) in central Japan, which has been much less affected by air pollution. The δS profiles at both sites are consistent with S air pollution and contributions of anthropogenic S. The minimum value in YOK is lower than the δS values of anthropogenic S or any other possible source. Because the δS in the tree rings is affected by fractionation in the forest ecosystems, we used a mixing model to account for the isotope effects and to distinguish the sources of S. Based on the model results, we infer that the peak of S emissions at YOK occurred sometime between the late 1960s and early 1970s (489 mmol m yr). This estimated value is comparable with the highest reported values in Europe. This is the first quantitative estimate of anthropogenic input of S in forest systems based on δS in tree rings. Our results suggest that tree ring data can be used when monitoring stations of atmospheric S are lacking and that estimates of S deposition using δS in tree rings will advance our understanding of the local-scale S dynamics and the effect of human activities on it.

A multi-enzyme electrode composed of FAD-dependent and NAD-dependent enzymes was fabricated using a poly-ruthenium complex (PAHA–Ru), which has two 1,10-phenanthroline-5,6-dione molecules as ligands. PAHA–Ru was used to immobilize FAD-dependent glucose dehydrogenase (FAD–GDH) onto an electrode and to examine PAHA–Ru containing the quinone moieties as an electron mediator. In cyclic voltammetry measurements of the FAD–GDH modified electrode in the presence of D-glucose, a catalytic current was obtained, which indicated electron transfer from FAD–GDH to PAHA–Ru. Our previous study has reported that PAHA–Ru with the quinone ligands also works as a mediator for NADH oxidation on an NAD-dependent alcohol dehydrogenase (NAD–ADH) modified electrode. Hence, FAD–GDH and NAD–ADH were co-immobilized with PAHA–Ru to make a multi-enzyme electrode. Using this multi-enzyme electrode as an anode, catalytic currents were observed in D-glucose solution, ethanol solution, and a mixed D-glucose and ethanol solution. The catalytic current in the mixed solution was greater than the currents obtained in the single substrate solutions, indicating bioelectrocatalysis reactions by the two enzymes and the single mediator in the mixed solution. Thus, we demonstrated that PAHA–Ru modified electrode enables selection of enzymes and their substrates from a wider range for enzymatic biofuel cells. Keywords: Redox polymer mediator, 1,10-Phenanthroline-5,6-dione, Flavin adenine dinucleotide dependent-glucose dehydrogenase, Nicotinamide adenine dinucleotide-dependent alcohol dehydrogenase, Multi-enzyme electrode, Entrapping immobilization method

A gene encoding an enzyme similar to a pyrroloquinoline quinone (PQQ)-dependent sugar dehydrogenase from filamentous fungi, which belongs to new auxiliary activities (AA) family 12 in the CAZy database, was cloned from Pseudomonas aureofaciens . The deduced amino acid sequence of the cloned enzyme showed only low homology to previously characterized PQQ-dependent enzymes, and multiple-sequence alignment analysis showed that the enzyme lacks one of the three conserved arginine residues that function as PQQ-binding residues in known PQQ-dependent enzymes. The recombinant enzyme was heterologously expressed in an Escherichia coli expression system for further characterization. The UV-visible (UV-Vis) absorption spectrum of the oxidized form of the holoenzyme, prepared by incubating the apoenzyme with PQQ and CaCl 2 , revealed a broad peak at approximately 350 nm, indicating that the enzyme binds PQQ. With the addition of 2-keto- d -glucose (2KG) to the holoenzyme solution, a sharp peak appeared at 331 nm, attributed to the reduction of PQQ bound to the enzyme, whereas no effect was observed upon 2KG addition to authentic PQQ. Enzymatic assay showed that the recombinant enzyme specifically reacted with 2KG in the presence of an appropriate electron acceptor, such as 2,6-dichlorophenol indophenol, when PQQ and CaCl 2 were added. 1 H nuclear magnetic resonance ( 1 H-NMR) analysis of reaction products revealed 2-keto- d -gluconic acid (2KGA) as the main product, clearly indicating that the recombinant enzyme oxidizes the C-1 position of 2KG. Therefore, the enzyme was identified as a PQQ-dependent 2KG dehydrogenase ( Pa 2KGDH). Considering the high substrate specificity, the physiological function of Pa 2KGDH may be for production of 2KGA.

This paper proposes a new approach for research on chat-like conversational systems that enable robots to acquire physically grounded knowledge through natural interaction with humans. The proposed approach combines research on chat-like conversational systems, language acquisition, and symbol grounding in order to realize physically situated and natural human-robot interaction. In contrast to previous approaches for chat-like conversation, the proposed approach focuses on utterances which are situated in physical environments surrounding humans and robots. Based on the proposed approach, we develop a concrete method that enables robots to learn object image concepts and the words describe them from object-teaching utterances made by humans. The method is composed of two processes:(1) the detection of object-teaching utterances from chat-like conversation and (2) the learning of object image concepts and the words describing them. It applies a linear support vector machine, multimodal hierarchical Dirichlet process, and term frequency-inverse document frequency process. The experimental results show that the method enabled robots to learn object image concepts and the words that describe them through multimodal chat-like interactions with humans.

Acetyl xylan esterase (AXE) catalyzes the hydrolysis of the acetyl bonds present in plant cell wall polysaccharides. Here, we determined the crystal structure of AXE from Aspergillus luchuensis ( Al AXEA), providing the three-dimensional structure of an enzyme in the Esterase_phb family. Al AXEA shares its core α/β-hydrolase fold structure with esterases in other families, but it has an extended central β-sheet at both its ends and an extra loop. Structural comparison with a ferulic acid esterase (FAE) from Aspergillus niger indicated that Al AXEA has a conserved catalytic machinery: a catalytic triad (Ser119, His259, and Asp202) and an oxyanion hole (Cys40 and Ser120). Near the catalytic triad of A lAXEA, two aromatic residues (Tyr39 and Trp160) form small pockets at both sides. Homology models of fungal FAEs in the same Esterase_phb family have wide pockets at the corresponding sites because they have residues with smaller side chains (Pro, Ser, and Gly). Mutants with site-directed mutations at Tyr39 showed a substrate specificity similar to that of the wild-type enzyme, whereas those with mutations at Trp160 acquired an expanded substrate specificity. Interestingly, the Trp160 mutants acquired weak but significant type B-like FAE activity. Moreover, the engineered enzymes exhibited ferulic acid-releasing activity from wheat arabinoxylan. IMPORTANCE Hemicelluloses in the plant cell wall are often decorated by acetyl and ferulic acid groups. Therefore, complete and efficient degradation of plant polysaccharides requires the enzymes for cleaving the side chains of the polymer. Since the Esterase_phb family contains a wide array of fungal FAEs and AXEs from fungi and bacteria, our study will provide a structural basis for the molecular mechanism of these industrially relevant enzymes in biopolymer degradation. The structure of the Esterase_phb family also provides information for bacterial polyhydroxyalkanoate depolymerases that are involved in biodegradation of thermoplastic polymers.

Electrons transfer from plasmonic nanoparticles to semiconductors by exploiting the energy of light, and this effect is applied to photovoltaics, photocatalysis, sensing, photochromisms, photoswitchable functionalities and nanofabrications., Recent development of nanoplasmonics has stimulated chemists to utilize plasmonic nanomaterials for efficient and distinctive photochemical applications, and physicists to boldly go inside the “wet” chemistry world. The discovery of plasmon-induced charge separation (PICS) has even accelerated these trends. On the other hand, some confusion is found in discussions about PICS. In this perspective, we focus on differences between PICS and some other phenomena such as co-catalysis effect and plasmonic nanoantenna effect. In addition, materials and nanostructures suitable for PICS are shown, and characteristics and features unique to PICS are documented. Although it is well known that PICS has been applied to photovoltaics and photocatalysis, here light is shed on other applications that take better advantage of PICS, such as chemical sensing and biosensing, various photochromisms, photoswitchable functionalities and nanoscale photofabrication.

This study developed a method for the simultaneous determination of erlotinib and its isomeric major metabolites, OSI-413 and OSI-420, in human plasma using an isocratic liquid chromatography–tandem mass spectrometry. Plasma specimens deproteinized with acetonitrile were separated using a 3-µm particle size octadecylsilyl column. The m/z values of the precursor and product ions for the analytes were as follows: erlotinib, 394.2/278.2; and OSI-413 and OSI-420, 380.2/278.2. The total run time was 21 min and no peaks interfering with the analytes and internal standard (d6-erlotinib) in human plasma were observed. The calibration curves of erlotinib, OSI-413 and OSI-420 were linear over the concentration ranges of 10–3000, 2–500 and 2–100 ng/mL, respectively. The pretreatment recovery ratios were >86.1%. The intra- and inter-assay precisions and accuracies were

Symbiotic protists in the gut of termites are prominent natural resources for enzymes involved in lignocellulose degradation. Here we report expression, purification, and biochemical characterization of a glycoside hydrolase family 26 mannanase RsMan26H from the symbiotic protist of the lower termite, Reticulitermes speratus. Biochemical analysis of RsMan26H demonstrates that this enzyme is an endo-processive mannobiohydrolase producing mannobiose from oligo- and polysaccharides, followed by a minor accumulation of oligosaccharides larger than mannobiose. To our knowledge, this is the first report describing the unique mannobiohydrolase enzyme from the eukaryotic origin.

Feruloyl esterase (FAE) catalyzes the hydrolysis of the ferulic and diferulic acids present in plant cell wall polysaccharides, and tannase catalyzes the hydrolysis of tannins to release gallic acid. The fungal tannase family in the ESTHER database contains various enzymes, including FAEs and tannases. Despite the importance of FAEs and tannases in bioindustrial applications, three-dimensional structures of the fungal tannase family members have been unknown. Here, we determined the crystal structure of FAE B from Aspergillus oryzae (AoFaeB), which belongs to the fungal tannase family, at 1.5 A resolution. AoFaeB consists of a catalytic α/β-hydrolase fold domain and a large lid domain, and the latter has a novel fold. To estimate probable binding models of substrates in AoFaeB, an automated docking analysis was performed. In the active site pocket of AoFaeB, residues responsible for the substrate specificity of the FAE activity were identified. The catalytic triad of AoFaeB comprises Ser203, Asp417, and His457, and the serine and histidine residues are directly connected by a disulfide bond of the neighboring cysteine residues, Cys202 and Cys458. This structural feature, the "CS-D-HC motif," is unprecedented in serine hydrolases. A mutational analysis indicated that the novel structural motif plays essential roles in the function of the active site.