Effects of copper on the decomposition of plant residues,microbial biomass,and β-glucosidase activity in soils

Abstract

Two types of soils (Brown Lowland soil and Ando soil), which were artificially enriched with different amounts of Cu, were incubated with or without pulverized orchard grass for 12 weeks at 25°C. For both soils with and without orchard grass amendment, the amount of CO₂ evolved over the 12-week period of incubation decreased by the enrichment with Cu at a concentration exceeding 1,000 mg kg^?1 soil. The decrease of the mineralization of added orchard grass in the Cu-enriched soil was conspicuous especially during the initial period of incubation. The amount of microbial biomass C at the end of the incubation was significantly reduced by the Cu enrichment regardless of the amendment with orchard grass. The relative decrease of the soil microbial biomass was much greater than that of the soil respiration. The amount of biomass C was negatively correlated with the amount of 0.1 M CaCl₂-extractable Cu as a logarithmic function. On the other hand, the β-glucosidase activity at the end of the incubation was not significantly affected by the presence of Cu in the soils without orchard grass amendment and increased with the increase in the amount of enriched Cu in the orchard grass-amended soils.     

Ready chemical conversion of acid hydrolysis lignin into water-soluble lignosulfonate III: Successive treatment of acid hydrolysis lignin and a lignin model compound by phenolation and arylsulfonation*

The chemical conversion of red pine sulfuric acid lignin (Klason lignin) (SAL) as an acid hydrolysis lignin sample to water-soluble arylsulfonates of lignin derivation (i.e., phenolized SAL) was investigated. Treatment of phenolized SAL with chlorosulfonic acid followed by alkali hydrolysis gave water-soluble sulfonated products with a sulfonic acid group on their aromatic nuclei quantitatively. The products possess 2.0 SO₃Na/C₉ C₆. In contrast, the content of sulfuric acid group in sulfonated SAL was only 0.33C₉. Chlorosulfonation of 1-guaiacyl-l-p-hydroxyphenylethane as a phenolized guaiacyl lignin model compound revealed that the sulfonyl chloride group was introduced at thepara position of an aromatic methoxyl group, theortho position of a phenolic hydroxyl group, or both.     

Bioremediation of organically enriched sediment deposited below fish farms with artificially mass-cultured colonies of a deposit-feeding polychaete <Emphasis Type="Italic">Capitella</Emphasis> sp. I

ABSTRACT:   For bioremediation of organically enriched sediment deposited below fish farms, the extremely high potential for population growth of a deposit-feeding polychaete, Capitella sp. I, in the organically enriched sediment, and the effect on decomposition of organic matter in the sediment, were examined. A mass-culturing technique was conducted for this species. Bioremediation experiments were conducted on the organically enriched sediment in a fish farm in Kusuura Bay, Japan in 2003–2006. Approximately 1.7 million individuals of the worms were placed on the sediment below one net pen in December 2003, 9.3 million individuals in November 2004, and 2.2 million individuals in November 2005. After the worms were spread on the sediment, they rapidly increased in number and reached the highest densities of approximately 134 000 inds/m² in February 2004, 527 000 inds/m² in March 2005 and 103 000 inds/m² in January 2006. In the process of rapid population growth, the decomposition of the organic matter of the sediment was enhanced markedly. Our results demonstrate that the promotion of population growth by spreading cultured colonies of Capitella can enhance the decomposition rate of organic matter markedly in organically enriched sediment below fish farms. This method is promising for minimization of the negative effects of fish farms.     

Adsorption of mercury by sugi wood carbonized at 1000°C

The ability of sugi wood carbonized at 1000°C to adsorb mercury was examined using aqueous solutions of mercuric chloride. Parameters studied include contact time, pH, adsorption temperature, and initial concentration of mercury in solution. Results showed that sugi wood carbonized at 1000°C could effectively remove mercury from aqueous solutions. The carbonized wood showed high adsorption ability for mercury at a wide pH range (pH 3–9), but its ability drastically decreased at pH 11. Adsorption decreased with increases in adsorption temperatures, indicating that the processes were exothermic in nature. Adsorption was found to follow the Freundlich isotherm model. The adsorption capacity of carbonized sugi wood was comparable to that of commercial activated carbon.     

Cytotoxic T-lymphocyte activity specific for hemagglutinin (H) protein of canine distemper virus in dogs

Cytotoxic T-lymphocyte (CTL) responses to hemagglutinin (H) protein of canine distemper virus (CDV) were evaluated in dogs using the replication-deficient adenovirus protein expression system. Skin fibroblasts were isolated from two dogs and were infected with recombinant adenovirus bearing the CDV-H gene (Ade-CDVH). CTL assay was performed using fibroblasts expressing CDV-H protein as target cells and peripheral blood lymphocytes (PBL) collected from the same dogs one week after immunization of CDV as effector cells. Specific cytotoxic activity was observed against autologous but not heterologous fibroblasts expressing CDV-H protein. These results indicate that the CTL epitope(s) were localized in the H protein.     

Innervation of the wing membrane in the bent-winged bat Miniopterus fuliginosus

The nerves that innervate the fingertips and wing membrane from the upper arm of the bent-winged bat Miniopterus fuliginosus were examined under a stereomicroscope. The radial, median, ulnar and musculocutaneous nerves were formed by the brachial plexus, which ran to the wing membrane. The two suspected axillary nerves ran to the wing membrane. The radial nerve ran to the end of the first digit, while the median nerve ran along the forearm and subsequently branched-off to run along the second to fifth digits up to the end of the phalanges. The ulnar nerve ran to the plagiopatagium on the extensor side of the elbow joint. Finally, the musculocutaneous nerve passed through the ventral side of the humerus and branched out at the elbow joint to run radially to the propatagium area. In this study, the visible nerves that were distributed from the upper arm to the fingertips of Miniopterus fuliginosus were formed by C6–T1.     

Daily ration of Japanese Spanish mackerel Scomberomorus niphonius larvae

SUMMARY: Diel successive samplings of Japanese Spanish mackerel Scomberomorus niphonius larvae were conducted throughout 24 h both in the sea and in captivity in order to estimate their daily ration. Using the Elliott and Persson model, the instantaneous gastric evacuation rate was estimated from the depletion of stomach contents (% dry bodyweight) with time during the night for wild fish (3.0–11.5 mm standard length) and from starvation experiments for reared fish (8, 10, and 15 days after hatching (DAH)). Japanese Spanish mackerel is a daylight feeder and exhibited piscivorous habits from first feeding both in the sea and in captivity. Feeding activity peaked at dusk. The estimated daily ration for wild larvae were 111.1 and 127.2% in 1996 and 1997, respectively; and those for reared larvae ranged from 90.6 to 111.7% of dry bodyweight. Based on the estimated value of daily rations for reared fish, the total number of newly hatched red sea bream Pagrus major larvae preyed by a Japanese Spanish mackerel from first feeding (5 DAH) to beginning of juvenile stage (20 DAH) in captivity was calculated to be 1139–1404.     

Nickel-catalyzed carbonization of wood for coproduction of functional carbon and fluid fuels II: improved fuel quality of oil fraction and increased heating value of gas fraction

The yields and properties of oil and gas fractions coproduced during carbonization of larch wood loaded with Ni 2%, Ni 2%+Ca 1%, and Ni 4% and without catalyst (None) at 700°–900°C were examined to clarify the catalytic effect in terms of conversion into fluid fuels. The net calorific value of oil occurred mainly below 500°C and increased in the order None < Ni 2% < Ni 4% < Ni 2%+Ca 1%, while the yield decreased in this order. The same order held for the production of gases enriched with hydrogen at 500°–700°C. Even above 800°C, markedly promoted evolution of hydrogen took place for all catalyst systems. These observations confirmed the effectiveness of nickel-catalyzed carbonization at 900°C, particularly Ni 2%+Ca 1%, for both upgrading of oil and gaseous fractions, although the quality of oil was not satisfactory. The catalysis of nickel with and without calcium is discussed on the basis of the modified Broid-Shafizadeh scheme, and the scheme was altered to adapt to the high temperature region where oil was no longer produced. Part of this study was presented at the 14th Annual Meeting of the Japan Institute of Energy, Suita, August 2005, and at the 18th Symposium, Session D, of the Materials Research Society of Japan, Tokyo, December 2007     

Development of room-temperature curing aqueous emulsion-type acrylic adhesive I: effect of monomer composition on the initial adhesive strength

For the purpose of developing a new aqueous emulsion-type adhesive for wood or paper use that does not release formaldehyde or volatile organic solvents, a honeymoon-type acrylic adhesive was examined. An adhesive system consisting of acrylic monomers copolymerized with functional monomers and a cross-linking agent was selected for the purposes of increasing initial adhesive strength and ensuring room-temperature curing. The initial adhesive strength increased by the use of cross-linkers such as dihydrazides and also polymeric methylene diphenyl diisocyanate (pMDI). Thus an adhesive with reasonable to good initial adhesive strength and room-temperature curing was obtained. The effect of pMDI on the initial adhesive strength was not significant and decreased when the amount of acrylamide in a copolymer was high.     

Pathogenicity of the pine wood nematode at different developmental stages

The ability of the pine wood nematode,Bursaphelenchus xylophilus, a pathogen that causes pine wilt disease, to kill cortical cells of Japanese black pine,Pinus thunbergii, during early development of the disease was conjectured to be a function of nematode developmental stage. A tangential segment of bark was removed from a 2-cm-long current-year stem. The cortex-exposed segments with cut cortical resin canals were designated as + RC-segments and those without them as − RC-segments. When a nematode population containing many older juveniles and adults (NL) was inoculated onto the cut surface, the − RC-segments were still alive 4 d after inoculation, as were non-inoculated control segments. When cortex-exposed segments were inoculated with either a nematode population containing many younger nematodes (NS) or with nematodes isolated from inoculated pine cuttings that also contained many younger juveniles, most tissue cells in − RC-segments died 4 d after inoculation, suggesting that younger juveniles killed pine cells directly, in contrast with older juveniles and adults. When nematodes were inoculated onto + RC-segments in which they could easily enter resin canals, both NL and NS killed the segment tissues. This suggests that NL is pathogenic to pine cells while living in resin canals. Such differences in the pathogenicity of NL and NS to pine parenchymatous cells were also demonstrated in a pathogenicity assay system using bark peelings, which allowed an estimate of direct attack on the cambial cells by nematodes. Based on these results, we hypothesize that younger juveniles are pathogenic to pine parenchymatous cells, while adults and older juveniles are not pathogenic. This work was supported in part by Grants-in-Aid for Scientific Research (No.01440012 and 06454088) and for Young Scientists (to K.I.) from Ministry of Education, Science, Culture, and Sports of Japan, and by a grant from PROBRAIN.