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91.
Summary Specially designed wood blocks from Norway spruce were used to study the nature of the fracture surfaces developed in shear using a tensile tester. In the case of the control (water-soaked blocks), the fracture in the latewood takes place mainly in the S1 layer while in the earlywood the fracture occurs across the double cell wall. After dilute alkali treatment, some earlywood cells also fracture in the S1 layer. For sulfite-treated samples, on the other hand, both earlywood and latewood fracture in the middle lamella.Financial support from the Empire State Paper Research Associates (ESPRA) is greatly appreciated 相似文献
92.
Tadashi Oikawa Toshiya Matsui Yasunori Matsuda Teruko Takayama Hitoshi Niinuma Yasuyo Nishida Kazuo Hoshi Mitsuyoshi Yatagai 《Journal of Wood Science》2006,52(2):140-146
Volatile organic compounds (VOCs) from wood and their effects on artifacts are of intense interest to museum staff who must
strictly manage the preservation environment. In this study, the causal substances of deterioration were inferred by comparison
with laser Raman (LR) spectra of deterioration products. The artifact samples were deteriorated using VOCs from woods (WV
test), and using specific substances that occur in wood VOCs (SV test). The deteriorated samples were analyzed by LR spectroscopy
and the results of the WV and SV tests were compared.
Hinokitiol and acetic acid were found to be two of the main causal substances of deterioration in western red cedar. Deterioration
of iron and copper by spruce did not appear to be caused by acetic acid, as is generally assumed, but by some other unknown
compound(s). Sensitivity to wood-based VOC components depended on the type of artifact. In western red cedar, mitsudasou (litharge) was very sensitive to acetic acid, while other artifacts were sensitive to hinokitiol. The LR method used in this
study is very useful for the inference of causal substances of deterioration based on the detection of small amounts of deteriorated
products such as those generated by deterioration due to wood VOCs.
Part of this article was presented at the 25th Annual Meeting of the Japan Society for the Conservation of Cultural Property,
Kyoto, June 2003 相似文献
93.
Estimation of the fine root biomass in a Japanese cedar (Cryptomeria japonica) plantation using minirhizotrons 总被引:1,自引:0,他引:1
Noguchi Kyotaro Sakata Tadashi Mizoguchi Takeo Takahashi Masamichi 《Journal of Forest Research》2004,9(3):261-264
We estimated fine root biomass in a Japanese cedar (Cryptomeria japonica) plantation using a min-irhizotron technique. Since data obtained from minirhizo-trons are limited to the length and diameter of fine roots observed on minirhizotron tubes, data conversion is necessary to determine the fine root biomass per unit soil volume or unit stand area. We first examined the regression between diameter squared and weight per unit length of fine roots in soil core samples, and calculated the fine root biomass on minirhizotron tubes from their length and diameter. Then we determined conversion factors based on the ratio of the fine root biomass in soil core samples to that on minirhizotron tubes. We examined calculation methods, using a single conversion factor for total fine root biomass in the soil for depths of 0–40cm (Cal1), or using four conversion factors for fine roots in the soil at 10-cm intervals (Cal2). Cal1 overestimated fine root biomass in the lower soil or underestimated that in the upper soil, while fine root biomass calculated using Cal2 better matched that in soil core samples. These results suggest that minirhizotron data should be converted separately for different soil depths to better estimate fine root biomass. 相似文献
94.
We examined the abrasive wear properties and the effect of abrasive grain size on the rate of wear when sugi wood (Cryptomeria japonica D.Don), compressed to various densities, was rubbed with abrasive paper. The results showed that the wear resistance of compressed wood increased linearly with the increased compression ratio; and under the condition of a low compression ratio it tended to be higher in comparison with the strength of compressed wood. The critical grain size effect, which can be witnessed during the abrasive wear of metals and plastics, was seen when low pressure was applied to the abrasive material. At higher pressures, the wear rate of the compressed wood increased with grain size, but the critical grain size effect was not observed. The pressure required to create the critical grain size effect was found to be higher than that needed for other types of uncompressed wood with the same yield properties.Part of this report was presented at the 50th Annual Meeting of the Japan Wood Research Society, Kyoto, April 2000 相似文献
95.
Gopalakrishnan S Subbarao GV Nakahara K Yoshihashi T Ito O Maeda I Ono H Yoshida M 《Journal of agricultural and food chemistry》2007,55(4):1385-1388
Nitrification inhibitory activity was found in root tissue extracts of Brachiaria humidicola, a tropical pasture grass. Two active inhibitory compounds were isolated by activity-guided fractionation, using recombinant Nitrosomonas europaea containing luxAB genes derived from the bioluminescent marine gram-negative bacterium Vibrio harveyi. The compounds were identified as methyl-p-coumarate and methyl ferulate, respectively. Their nitrification inhibitory properties were confirmed in chemically synthesized preparations of each. The IC50 values of chemically synthesized preparations were 19.5 and 4.4 microM, respectively. The ethyl, propyl, and butyl esters of p-coumaric and ferulic acids inhibited nitrification, whereas the free acid forms did not show inhibitory activity. 相似文献
96.
Ai ORIME Tomohiro YONEZAWA Hideki OGASAWARA Tadashi KUROYANAGI Tomiharu MANDA 《Animal Science Journal》2012,83(3):268-271
A questionnaire based on sensory evaluation of completely domestic grass‐fed beef was carried out on 157 Japanese undergraduate students aged between 18 and 22 years in Kitasato University. The sensory evaluation sheet consisted of 10 questions concerning preference for domestic grass‐fed beef, and three demographic/lifestyle questions. Using principal component analysis and cluster analysis, the respondents were divided into four groups (G1–G4). G1 accepted almost all properties. G2 accepted most properties but disliked chewiness. G3 accepted juiciness and flavor but disliked the color and texture of the meat. G4 tended to dislike almost all properties. According to chi‐square test, most G2‐people statistically liked other commercial beef and G4‐people had neutral and negative impressions. G1‐ or G3‐people did not have any significant tendency as regards beef preference. These results indicate that most of the young respondents who preferred domestic grass‐fed beef could not accept its texture, and some respondents could accept its juiciness and flavor. It is also suggested that a part of the people who like commercial beef do not prefer chewiness of grass‐fed beef. Such information will aid grass‐fed beef cattle breeders, producers and packers to improve the quality of beef and its evaluation. 相似文献
97.
Maiko Sato Ashraf M Ahmed Ayako Noda Hitoshi Watanabe Yukio Fukumoto Tadashi Shimamoto 《Acta veterinaria Scandinavica》2009,51(1):46
Imported animals, especially those from developing countries, may constitute a potential hazard to native animals and to public health. In this study, a new flock of lesser flamingos imported from Tanzania to Hiroshima Zoological Park were screened for multidrug-resistant Gram-negative bacteria, integrons and antimicrobial resistance genes. Thirty-seven Gram-negative bacterial isolates were obtained from the flamingos. Seven isolates (18.9%) showed multidrug resistance phenotypes, the most common being against: ampicillin, streptomycin, tetracycline, trimethoprim/sulfamethoxazole and nalidixic acid. Molecular analyses identified class 1 and class 2 integrons, β-lactamase-encoding genes, blaTEM-1 and blaCTX-M-2 and the plasmid-mediated quinolone resistance genes, qnrS and qnrB. This study highlights the role of animal importation in the dissemination of multidrug-resistant bacteria, integrons and antimicrobial resistance genes from one country to another. 相似文献
98.
Itagaki T Kikawa M Terasaki K Shibahara T Fukuda K 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2005,67(11):1115-1118
Nucleotide sequences of ribosomal internal transcribed spacer (ITS1) and mitochondrial NADH dehydrogenase I (NDI) gene were analyzed to genetically characterize aspermic Fasciola forms in Korea. From the difference in ITS1 sequences, Korean flukes were divided into 3 haplotypes represented by Kor1, Kor2 and Kor1/2, which had nucleotides identical to F. hepatica, F. gigantica and those overlapped between the two species, respectively. NDI sequences also showed that Korean flukes could be classified into 3 distinct haplotypes (Kor1: F. hepatica-type, Kor2a and Kor2b: F. gigantica-type). The sequences of Kor1 and Kor2a were 100% identical to those of the haplotypes Fsp1and Fsp2, respectively, which are major Fasciola forms in Japan. These findings strongly suggest that aspermic Fasciola forms in Korea and Japan originated from same ancestors and have recently spread throughout both countries. 相似文献
99.
Sano T King JN Seewald W Sakakibara N Okumura M 《Veterinary journal (London, England : 1997)》2012,193(2):397-403
The objective of the study was to evaluate the efficacy and tolerability of robenacoxib, a selective cyclooxygenase-2 inhibitor, for the treatment of acute pain and inflammation associated with musculoskeletal disorders in cats. The study was a prospective, multi-centre, randomised, blinded, non-inferiority design clinical trial comparing robenacoxib to ketoprofen. A total of 68 cats presenting with pain and inflammation associated with acute musculoskeletal disorders were recruited and allocated randomly to receive, orally once daily for 5-6days, either 1.0-2.4mg/kg robenacoxib (n=47) or 1mg/kg ketoprofen (n=21). The primary efficacy endpoint was the total clinician score, which was the sum of clinician numerical rating scale scores for pain, inflammation and mobility. Assessments were made at baseline, on day 2, and day 4 or 5. For the total clinician score, non-inferior efficacy of robenacoxib was demonstrated with a relative efficacy of 1.151 (95% confidence interval 0.872-1.494). Non-inferior efficacy of robenacoxib was also demonstrated for the secondary endpoint of the total owner score. Robenacoxib was superior (P<0.05) to ketoprofen for the owner's assessment of activity and human/animal relationship. The tolerability of both treatments was good as assessed by monitoring adverse events, clinical signs and haematology and serum biochemistry variables. 相似文献
100.
Itagaki T Kinoshita S Aoki M Itoh N Saeki H Sato N Uetsuki J Izumiyama S Yagita K Endo T 《Veterinary parasitology》2005,133(4):283-287
To determine the genotypes of Giardia intestinalis from domestic and wild animals in Japan, Giardia isolates obtained from feces of 24 dogs kept in households and breeding kennels, three companion cats, five dairy calves and three wild monkeys, Macaca fuscata, were genotyped using the 177 bp sequence of the glutamete dehydrogenase gene (gdh). The genotypes were assemblages A, C, D or A/D for dog isolates, Assemblage F for cat isolates, assemblages A or E for calf isolates and assemblage B for monkey isolates. This is the first report on the genotypes of Giardia isolates from cats, calves and wild monkeys in Japan. 相似文献