Mitsubishi Gas Chemical (Japan)

Terrestrial moisture recycling by evapotranspiration has recently been recognised as an important source of precipitation that can be characterised by its isotopic composition. Up to now, this isotope technique has mainly been applied to moisture recycling in some humid regions, including Brazil, Great Lakes in North America and the European Alps. In arid and semi-arid regions, the contribution of transpiration by plants to local moisture recycling can be small, so that evaporation by bare soil and surface water bodies dominates. Recognising that the deuterium excess (d-excess) of evaporated moisture is significantly different from that of the original water, we made an attempt to use this isotopic parameter for estimating moisture recycling in the semi-arid region of Eastern Tianshan, China. We measured the d-excess of samples taken from individual precipitation events during a hydrological year from 2003 to 2004 at two Tianshan mountain stations, and we used long-term monthly average values of the d-excess for the station Urumqi, which are available from the International Atomic Energy AgencyWorld Meteorological Organization (IAEAWMO) Global Network of Isotopes in Precipitation (GNIP). Since apart from recycling of moisture from the ground, sub-cloud evaporation of falling raindrops also affects the d-excess of precipitation, the measured values had to be corrected for this evaporation effect. For the selected stations, the sub-cloud evaporation was found to change between 0.1 and 3.8%, and the d-excess decreased linearly with increasing sub-cloud evaporation at about 1.1 per 1% change of sub-cloud evaporation. Assuming simple mixing between advected and recycled moisture, the recycled fraction in precipitation has been estimated to be less than 2.090.6% for the Tianshan mountain stations and reach values up to 15.090.7% in the Urumqi region. The article includes a discussion of these findings in the context of water cycling in the studied region.

Plant-associated bacteria were characterized and are discussed in relation to authentic members of the genus Pseudomonas sensu stricto. Bacteria belonging to Pseudomonas rRNA group II are separated clearly from members of the genus Pseudomonas sensu stricto (Pseudomonas fluorescens rRNA group) on the basis of plant association characteristics, chemotaxonomic characteristics, DNA-DNA hybridization data, rRNA-DNA hybridization data, and the sequences of 5S and 16S rRNAs. The transfer of Pseudomonas cepacia, Pseudomonas mallei, Pseudomonas pseudomallei, Pseudomonas caryophylli, Pseudomonas gladioli, Pseudomonas pickettii, and Pseudomonas solanacearum to the new genus Burkholderia is supported; we also propose that Pseudomonas plantarii and Pseudomonas glumae should be transferred to the genus Burkholderia. Isolate VA-1316T (T = type strain) was distinguished from Burkholderia species on the basis of physiological characteristics and DNA-DNA hybridization data. A new species, Burkholderia vandii sp. nov. is proposed for this organism; the type strain of B. vandii is VA-1316 (= JCM 7957).

Stable battery operation of a bulk-type all-solid-state lithium-sulfur battery was demonstrated by using a LiBH4 electrolyte. The electrochemical activity of insulating elemental sulfur as the positive electrode was enhanced by the mutual dispersion of elemental sulfur and carbon in the composite powders. Subsequently, a tight interface between the sulfur-carbon composite and the LiBH4 powders was manifested only by cold-pressing owing to the highly deformable nature of the LiBH4 electrolyte. The high reducing ability of LiBH4 allows using the use of a Li negative electrode that enhances the energy density. The results demonstrate the interface modification of insulating sulfur and the architecture of an all-solid-state Li-S battery configuration with high energy density.

Pyrroloquinoline quinone (PQQ), an aromatic tricyclic o-quinone, was identified initially as a redox cofactor for bacterial dehydrogenases. Although PQQ is not biosynthesized in mammals, trace amounts of PQQ have been found in human and rat tissues because of its wide distribution in dietary sources. Importantly, nutritional studies in rodents have revealed that PQQ deficiency exhibits diverse systemic responses, including growth impairment, immune dysfunction, and abnormal reproductive performance. Although PQQ is not currently classified as a vitamin, PQQ has been implicated as an important nutrient in mammals. In recent years, PQQ has been receiving much attention owing to its physiological importance and pharmacological effects. In this article, we review the potential health benefits of PQQ with a focus on its growth-promoting activity, anti-diabetic effect, anti-oxidative action, and neuroprotective function. Additionally, we provide an update of its basic pharmacokinetics and safety information in oral ingestion.

We have synthesized a new photochromic compound that exhibits unusual negative photochromism, in which the stable colored species photochemically converts into the metastable colorless species via a short-lived radical. This compound has a 1,1'-binaphthyl moiety bridging the two diphenylimidazole units. Its photochemical properties were investigated by nanosecond laser flash photolysis. The colored species isomerizes to the colorless species upon exposure to visible light and thermally returns to the original colored species within 20 min at room temperature. Moreover, the photodecoloration reaction proceeds via a short-lived radical with a half-life of 9.4 μs in benzene at room temperature. Both the colored and colorless species show the photoinduced homolytic bond cleavage reaction of the C-N bond between the nitrogen atom of the imidazole ring and the carbon atom of the 1-position of the 1,1'-binaphthyl moiety and that of the C-C bond between each of the carbon atoms of the 2-position of the imidazole ring, respectively, followed by their formation by rapid radical coupling.

Two methylamine- and N,N-dimethylformamide-utilizing Paracoccus spp. are described. These bacteria are gram-negative, nonsporeforming, nonmotile, coccoid or short rod-shaped organisms. Their DNA base composition is 62 to 68 mol% G + C. Their cellular fatty acids include large amounts of C18:1 acid. Their major hydroxy acids are 3-OH C10:0 and 3-OH C14:0 acids. The major ubiquinone is Q-10. These bacteria are distinguished from Paracoccus denitrificans and Paracoccus alcaliphilus by physiological characteristics and by DNA-DNA-homology. Paracoccus aminophilus sp. nov. and Paracoccus aminovorans sp. nov. are proposed. The type strain of P. aminophilus is DM-15 (= JCM 7686), and the type strain of P. aminovorans is DM-82 (= JCM 7685). Paracoccus halodenitrificans is distinguished from other Paracoccus species on the basis of cellular fatty acid composition, hydroxy fatty acid composition, and DNA-DNA homology. It may not be a valid member of the genus Paracoccus.

We have prepared a carbon film of nanometer thickness, which is called here a carbon nanofilm (CNF), starting from the oxidation of graphite. The structure and thickness of the CNF are determined by high-resolution transmission electron microscopy and electron diffraction. The structure is of a new type (S.G.: P3), in which carbon six-membered-ring planes are stacked with the sequence of ...AA.... According to electron energy loss spectroscopy, a substantial amount of oxygen is detected but the molar ratio of oxygen to carbon is possibly decreased to less than 0.1. The CNF changes from an insulator to a semiconductor when reduced on heating at 250°C.

Abstract Hydrogen peroxide is produced from hydrogen gas and air in industry by using the anthraquinone process. The mechanism for the production of hydrogen peroxide in this process is studied by using DFT calculations and reaction rate measurements. A hydrogen atom of anthrahydroquinone (AHQ) is directly abstracted by triplet dioxygen to produce a hydroperoxide radical (HOO · ) and a 10‐hydroxy‐9‐anthroxyl radical (AQH · ), followed by subsequent hydrogen atom abstraction that leads to the formation of hydrogen peroxide and anthraquinone (AQ). Hydrogen atom abstraction was found to be the rate‐determining step in this process. Tetrahydroanthrahydroquinone (THAHQ) is also used in this process in a similar way to AHQ, but a higher activation energy is required for the rate‐determining step when THAHQ is used, which would lead to a 25‐fold rate deacceleration compared with AHQ at 27 °C. The reactivities of AHQ and THAHQ are not significantly influenced by effects of side alkyl chain that is used in the industrial process for increasing the solubility of AHQ and AQ in working solution. The relative reaction rate of AHQ and THAHQ is measured under laboratory conditions. The computational results are consistent with an observed lower rate of the oxidation process of THAHQ.

In order to clarify the existence of a single sheet of carbon six-membered-ring plane (graphene) this letter presents a method by which the stacking number of the sheets in a carbon nanofilm (CNF) can be exactly counted, based on the quantitative analysis of electron diffraction intensity. Using the method we can detect a single graphene sheet in a CNF.

BACKGROUND: Graphene oxide (GO) is a single layer carbon sheet with a thickness of less than 1 nm. GO has good dispersibility due to surface modifications with numerous functional groups. Reduced graphene oxide (RGO) is produced via the reduction of GO, and has lower dispersibility. We examined the bioactivity of GO and RGO films, and collagen scaffolds coated with GO and RGO. METHODS: GO and RGO films were fabricated on a culture dish. Some GO films were chemically reduced using either ascorbic acid or sodium hydrosulfite solution, resulting in preparation of RGO films. The biological properties of each film were evaluated by scanning electron microscopy (SEM), atomic force microscopy, calcium adsorption tests, and MC3T3-E1 cell seeding. Subsequently, GO- and RGO-coated collagen scaffolds were prepared and characterized by SEM and compression tests. Each scaffold was implanted into subcutaneous tissue on the backs of rats. Measurements of DNA content and cell ingrowth areas of implanted scaffolds were performed 10 days post-surgery. RESULTS: The results show that GO and RGO possess different biological properties. Calcium adsorption and alkaline phosphatase activity were strongly enhanced by RGO, suggesting that RGO is effective for osteogenic differentiation. SEM showed that RGO-modified collagen scaffolds have rough, irregular surfaces. The compressive strengths of GO- and RGO-coated scaffolds were approximately 1.7-fold and 2.7-fold greater, respectively, when compared with the non-coated scaffold. Tissue ingrowth rate was 39% in RGO-coated scaffolds, as compared to 20% in the GO-coated scaffold and 16% in the non-coated scaffold. CONCLUSION: In summary, these results suggest that GO and RGO coatings provide different biological properties to collagen scaffolds, and that RGO-coated scaffolds are more bioactive than GO-coated scaffolds.

Si 3 N 4 /SiC composites are ceramic materials that exhibit excellent performance for high‐temperature applications. Prepared from an ultrafine amorphous Si‐C‐N powder, sintered materials are constituted mainly of a β ‐Si 3 N 4 matrix with SiC inclusions and have a very small grain size (less than 1 μm). Such a microstructure is propitious for superplastic forming. Superplasticity has been studied in tension, from 1550° to 1650°C, under nitrogen atmosphere. Elongations over 100% have been achieved. In many cases, at the highest temperatures and slowest strain rates, materials are damaged by different processes, including microcracking, cavitation, and chemical decomposition. A map of the most suitable (strain‐rate/temperature) domain has been established. It allows the prevention of any structural alteration by selecting carefully the testing conditions. Since specimens suffered considerable strain‐induced hardening, sources for this phenomenon are examined. Although the experiments have involved high temperature and extensive strain, neither static nor dynamic grain growth has occurred. Crystallization of the amorphous grain‐boundary phase, which is reported in most cases, may be invoked. However, based on microstructural observations, it is not the unique origin for flow hardening.

The effects of pyrroloquinoline quinone (PQQ) and coenzyme Q(10) (Co Q(10)), either alone or together, on the learning ability and memory function of rats were investigated. Rats fed a PQQ-supplemented diet showed better learning ability than rats fed a CoQ(10)-supplemented diet at the early stage of the Morris water maze test. The combination of both compounds resulted in no significant improvement in the learning ability compared with the supplementation of PQQ alone. At the late stage of the test, rats fed PQQ-, CoQ(10)- and PQQ + CoQ(10)-supplemented diets showed similar improved learning abilities. When all the groups were subjected to hyperoxia as oxidative stress for 48 h, rats fed the PQQ- and CoQ(10) supplemented diets showed better memory function than the control rats. The concurrent diet markedly improved the memory deficit of the rats caused by oxidative stress. Although the vitamin E-deficient rats fed PQQ or CoQ(10) improved their learning function even when subjected to hyperoxia, their memory function was maintained by PQQ rather than by CoQ(10) after the stress. These results suggest that PQQ is potentially effective for preventing neurodegeneration caused by oxidative stress, and that its effect is independent of either antioxidant's interaction with vitamin E.

Graphene oxide (GO) possesses the desirable characteristic of aqueous solution processability attributed to the oxygen-containing functional groups on the basal planes and edges of graphene. To provide an alternative to conventional procedures for fabricating poly (methyl methacrylate) (PMMA)/GO nanocomposites, which use organic solutions and/or surfactants, we have developed an environmentally friendly technique in which PMMA is polymerized by soap-free emulsion polymerization and incorporated with GO using water as a processing medium. Experimental results showed that the fabricated PMMA/GO nanocomposites had excellent mechanical, thermal, and O2 barrier properties with the nanodispersion of GO.

BACKGROUND: Nonenzymatic glycation of neural proteins and their end-products (advanced glycation end-products, AGE) have been implicated in the pathogenesis of diabetic neuropathy. We need a development of effective ant-glycation agents for future clinical use. MATERIALS AND METHODS: We examined the effects of OPB-9195 (OPB), a new inhibitor of glycation, on the peripheral nerve structure and function in diabetic rats. Eight-week-old Wistar rats were made diabetic by streptozotocin (40 mg kg(-1), i.v.) and OPB (60 mg kg(-1) day(-1)) was given by gavage for 24 weeks. Age- and sex-matched normal Wistar rats were used for comparison. RESULTS: During the experimental period, OPB treatment did not affect the reduced body weight, elevated levels of blood glucose and glycated haemoglobin in diabetic rats. At the end of the experiment, delayed tibial motor nerve conduction velocity was significantly improved (by 60%) in treated diabetic rats, with reduction of serum AGE levels. Expression of immunoreactive AGE in the sciatic nerve was reduced in treated diabetic rats compared with those in untreated rats. Sciatic nerve (Na+, K+)-ATPase activity was also restored in treated diabetic rats. On the cross-sectioned sciatic nerves, positive cells with oxidative stress-related DNA damage, as expressed by 8-hydroxy-2'-deoxyguanosine, were less in the peripheral nerve of treated diabetic rats compared with those of untreated rats. CONCLUSION: The current study suggested that OPB is beneficial for the reduction of serum AGE and the prevention of diabetic neuropathy.

A new genus of acidophilic, facultatively methylotrophic bacteria is described. These organisms are gram-negative, nonsporeforming, nonmotile, and rod shaped and grow at pH 2.0 to 5.5. These characteristics are unique among the methanol-utilizing bacteria. The deoxyribonucleic acid base composition is 63 to 65 mol% guanine plus cytosine. Acetobacter methanolicus TK 0705T (T = type strain) is a typical strain in this group. These bacteria are distinguished from type and representative strains of Acetobacter, Gluconobacter, Acidiphilium, and Thiobacillus on the basis of deoxyribonucleic acid-deoxyribonucleic acid homology. A new genus, Acidomonas, is proposed to include this group.of methylotrophic bacteria. The type species of the genus Acidomonas is Acidomonas methanolica comb, nov., with type strain TK 0705 (= IMET 10945).

A successful electrospun polyoxymethylene (POM) nanofiber using a hexafluoroisopropanol (HFIP)-based solvent is reported. The nanofibers obtained show a significant nanoporous surface as a consequence of the spinning conditions, i.e. spinning voltage and relative humidity, as well as the polymer/solvent properties. The oxyethylene unit in the polyoxymethylene copolymer decreases the nanofiber surface roughness and porosity, leading to a significant change in the specific surface area. A slight change in the molecular weight of the POM after electrospinning confirms that the nanofiber with nanoporous POM barely degrades or decomposes during the spinning. The electrospun POM nanofiber gives an inevitable nanoporous structure with high specific surface area (as much as 2−3 times higher) compared to those of the nonporous electrospun nylon-6 and porous electrsopun PAN reported in the past.

We compared non-methane-, non-methanol-, and methylamine-utilizing bacteria, including Pseudomonas aminovorans, a tetramethylammonium-utilizing bacterium, and an N-N-dimethylformamide-utilizing bacterium. These bacteria are gram-negative, nonsporeforming, subpolarly flagellated, rod-shaped organisms. Reproduction occurs by budding. The DNA base compositions are 62 to 64 mol% guanine plus cytosine. The cellular fatty acids contain a large amount of C18:1 acid. The major hydroxy acid is 3-OH C12:0 acid. The major ubiquinone is ubiquinone Q-10. These bacteria are clearly separated from authentic Pseudomonas species (Pseudomonas fluorescens rRNA group) on the basis of utilization of methylamine, morphological and chemotaxonomic characteristics, DNA-DNA homology, and rRNA-DNA homology. They were divided into three subgroups on the basis of their physiological characteristics and DNA-DNA homology data. A new genus, Aminobacter, and three new species, Aminobacter aminovorans comb. nov., Aminobacter aganoensis sp. nov., and Aminobacter niigataensis sp. nov., are proposed. The type species of Aminobacter gen. nov. is A. aminovorans, with type strain JCM 7852. The type strain of A. aganoensis is strain TH-3 (= JCM 7854), and the type strain of A. niigataensis is strain DM-81 (= JCM 7853).

Pyrroloquinoline quinone (PQQ), a redox-active o-quinone found in various foods and mammalian tissues, has received an increasing amount of attention because of a number of health benefits that can be attributed to its ability to enhance mitochondrial biogenesis. However, its underlying molecular mechanism remains incompletely understood. We have now established that the exposure of mouse NIH/3T3 fibroblasts to a physiologically relevant concentration of PQQ significantly stimulates mitochondrial biogenesis. The exposure of NIH/3T3 cells to 10–100 nM PQQ for 48 h resulted in increased levels of Mitotracker staining, mitochondrial DNA content, and mitochondrially encoded cytochrome c oxidase subunit 1 (MTCO1) protein. Moreover, we observed that PQQ treatment induces deacetylation of the peroxisome proliferator-activated receptor-γ-coactivator 1α (PGC-1α) and facilitates its nuclear translocation and target gene expression but does not affect its protein levels, implying increased activity of the NAD+-dependent protein deacetylase sirtuin 1 (SIRT1). Indeed, treatment with a SIRT1 selective inhibitor, EX-527, hampered the ability of PQQ to stimulate PGC-1α-mediated mitochondrial biogenesis. We also found that the PQQ treatment caused a concentration-dependent increase in the cellular NAD+ levels, but not the total NAD+ and NADH levels. Our results suggest that PQQ-inducible mitochondrial biogenesis can be attributed to activation of the SIRT1/PGC-1α signaling pathway by enhancing cellular NAD+ formation.

Abstract The rapid expansion from a supercritical solution with a nonsolvent (RESS‐N) was applied to the formation of polymeric microcapsules containing medicines such as p ‐acetamidophenol, acetylsalicylic acid, 1,3‐dimethylxanthine, flavone, and 3‐hydroxyflavone. A suspension of medicine in carbon dioxide (CO 2 ) containing a cosolvent and dissolved polymer was sprayed through a nozzle to atmospheric pressure. The pre‐expansion pressure was 10–25 MPa, and the temperature was 308–333 K. The polymers were poly( L ‐lactic acid) (molecular weight = 5000), poly(ethylene glycol) (PEG; PEG4000, molecular weight = 3000; PEG6000, molecular weight = 7500; and PEG20000, molecular weight = 20,000), poly(methyl methacrylate) (molecular weight = 15,000), ethyl cellulose (molecular weight = 5000), and PEG–poly(propylene glycol)–PEG triblock copolymer (molecular weight = 13,000). The solubilities of the polymers as coating materials and these medicines as core substance were very low in CO 2 . However, the solubilities of these polymers in CO 2 significantly increased with the addition of low molecular weight alcohols as cosolvents. After RESS‐N, polymeric microcapsules were formed according to the precipitation of the polymer caused by a decrease in the solvent power of CO 2 . This method offered three advantages: (1) enough of the coating polymers, which were insoluble in pure CO 2 , dissolved; (2) the microparticles of the medicine were encapsulated without adhesion between the particles because a nonsolvent was used as a cosolvent and the cosolvent remaining in the mixture was removed by the gasification of CO 2 ; and (3) the polymer‐coating thickness was controlled with changes in the feed composition of the polymer for drug delivery. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 742–752, 2003

Several microorganisms were isolated as bacteria degrading polycaprolactone (PCL), and one of them, a strain B273 identified as Alcaligenes faecalis, was selected. Because this strain produced only slight PCL depolymerase activity, the hyperproducing mutant, TS22, was isolated after UV irradiation. Synthesis of PCL depolymerase was derepressed, probably based on the altered regulation of metabolic pathways in strain TS22. The partially purified enzyme hydrolyzed p-nitrophenyl fatty acids and triglycerides other than PCL, but not poly(3-hydroxybutyrate), indicating that PCL depolymerase may be a kind of lipase.