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111.
Liquefaction of beech wood in various supercritical alcohols   总被引:1,自引:0,他引:1  
The liquefaction of Japanese beech (Fagus crenata Blume) was studied with various straight-chain alcohols in subcritical and supercritical states using a batch-type reaction vessel to obtain liquid fuel from lignocellulosics. Under the reaction condition of 270°C, beech wood was liquefied to some extent in all alcohols with about 50%–65% insoluble residue left after treatment for 30min. Under the condition of 350°C, however, more than 90% of wood was decomposed and liquefied in all alcohols. Alcohols with longer alkyl chains liquefied lignocellulosics in shorter reaction times. Because many kinds of alcohols, such as methanol and ethanol, can be produced from biomass, 100% biomass-based liquid fuel can be prepared by supercritical alcohol technology when using such bioalcohols. This study was presented in part at the 55th Annual Meeting of the Japan Wood Research Society, Kyoto, Japan, March 16–18, 2005  相似文献   
112.
Since the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, we have established an archive system of livestock and wild animals from the surrounding ex-evacuation zone. Wildlife within the alert zone have been exposed to low-dose-rate (LDR) radiation for a long continuous time. In this study, we analysed the morphological characteristics of the testes and in vitro fertilization (IVF) capacity of cryopreserved sperm of racoons from the ex-evacuation zone of the FDNPP accident. The radioactivity of caesium-137 (137Cs) was measured by gamma-ray spectrometry, and the measured radioactivity concentration was 300–6,630 Bq/kg in the Fukushima raccoons. Notably, normal spermatogenesis was observed in the seminiferous tubules of the testes, with the germinal epithelium composed of a spermatogenic cell lineage with no evident ultrastructural alterations; freeze-thawing sperm penetration ability was confirmed using the interspecific zona pellucida-free mouse oocytes IVF assays. This study revealed that the chronic and LDR radiation exposure associated with the FDNPP accident had no adverse effect on the reproductive characteristics and functions of male raccoons.  相似文献   
113.
Patulin is a mycotoxin produced by mainly Penicillium species, for example, P. expansum, and Aspergillus species. There are several reports of patulin contamination in apple juice. Last year, the Ministry of Health, Labour and Welfare of Japan set the maximum allowable level of patulin in apple juice at 50 ppb and decided that the measurement of patulin levels in apple juice products should be conducted. To this end, a simple, accurate, and selective analytical method for the detection of patulin at levels lower than 5 ppb, the detection limit, is desired. This paper reports the development of an analytical method that employs solid-phase extraction-liquid chromatography-mass spectrometry (SPE-LC-MS). When MS measurements were conducted with the selected ion monitoring (SIM) mode, the pseudomolecular ions at m/z 153 and 156 were used to monitor patulin and (13)C(3)-labeled patulin, respectively. The detection limit (S/N = 3) and the quantification limit (S/N = 10) of patulin at injection levels into LC-MS were 12.5 and 25 pg, respectively. However, when the actual sample was applied for the analysis based on the developed method including the sample preparation, the detection limit (S/N = 3) and quantification limit (S/N = 10) were 2.5 and 5 pg in sample, respectively. The calibration curve obtained for concentrations ranging from 5 to 500 ppb showed good linearity with a coefficient of determination (r (2)) of 0.999. In addition, the recovery was >95% when an internal standard was used. The method was applied to the analysis of 76 apple juice samples from Japan, and as a result, patulin levels ranging from <1.0 to 45 ppb (detection frequency = 15/76) were detected. In this study, it was found that patulin was a greater contaminant in concentration/reduction than in "not from concentrate" apple juice.  相似文献   
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Pathogenicity of a fowl adenovirus (FAV), JM1/1 strain of serotype 1 derived from gizzard erosions of a broiler chicken, was examined to specific pathogen-free (SPF) chickens pre-treated with infectious bursal disease viruses (IBDVs) or cyclophosphamide (CY). Virulent IBDVs, classical type, were inoculated orally at 3 days of age of SPF chickens. CY was treated subcutaneously for 3 days after hatch. FAV was given orally at 30 days of age. At 40 days of age, all chickens were bled and autopsied for serology and gross observation. Gizzard lesions were ranked by the scores depending on their severities. IBDV- or CY-treated chickens showed significantly higher gizzard lesion scores than non treated birds. There were no gross lesions in any other organs except for bursal atrophy. Serologically, antibody production against FAV was highly suppressed by IBDV infection or CY treatment.  相似文献   
117.
We examined the effects of heat stress (HS) on production traits, somatic cell score (SCS) and conception rate at first insemination (CR) in Holsteins in Japan. We used a total of 228 242 records of milk, fat and protein yields, and SCS for the first three lactations, as well as of CR in heifers and in first‐ and second‐lactation cows that had calved for the first time between 2000 and 2012. Records from 47 prefectural weather stations throughout Japan were used to calculate the temperature–humidity index (THI); areas were categorized into three regional groups: no HS (THI < 72), mild HS (72 ≤ THI < 79), and moderate HS (THI ≥ 79). Trait records from the three HS‐region groups were treated as three different traits and trivariate animal models were used. The genetic correlations between milk yields from different HS groups were very high (0.91 to 0.99). Summer calving caused the greatest increase in SCS, and in the first and second lactations this increase became greater as THI increased. In cows, CR was affected by the interaction between HS group and insemination month: with summer and early autumn insemination, there was a reduction in CR, and it was much larger in the mild‐ and moderate‐HS groups than in the no‐HS group.  相似文献   
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1. The aim of this work was to select lactic acid bacteria (LAB) strains from chicks and hens of egg-laying strains for potential use to control Salmonellae.

2. Nineteen LAB strains obtained from culture collections, and 24 strains isolated from excreta of laying hens and chicks, were evaluated for inhibitory capacities against two Salmonella serotypes using a “Spot-the-lawn” technique and other in vitro properties that could be predictive of antimicrobial activity.

3. The size of the inhibition zone differed slightly between Salmonella serotypes, however, the mean size of the Salmonella inhibition zone differed greatly among the LAB strains. Lactobacillus salivarius, L. plantarum, L. rhamnosus and L. reuteri exhibited powerful inhibitory effects to each Salmonella strain.

4. The result of the acid tolerance test showed that all L. salivarius, L. kitasatonis strains and each of L. ingluviei cannot survive in a low pH environment. In the bile acid tolerance assay, growth was inhibited in all strains, except L. kitasatonis HE4, and a large inhibition was observed in most of the L. salivarius and L. crispatus strains.

5. The results demonstrate that some LAB of poultry origin were able to inhibit the growth of Salmonella and survive simulated passage through the gastrointestinal tract. The selected LAB could act in the lower gastrointestinal tract to prevent salmonellosis in poultry.  相似文献   

120.
Participation of nitric oxide, vasoactive intestinal peptide (VIP) and pituitary adenylate cyclase activating peptide (PACAP) in nonadrenergic, noncholinergic (NANC) relaxation of longitudinal muscle of various intestinal regions in Sprague Dawley rats (8-week-old) was studied in vitro. Nitric oxide was suggested to participate in NANC relaxation of every intestinal region studied. But the participation was partial and its extent varied among the regions: significant in the proximal colon and rectum, and moderate in the jejunum, ileum and distal colon. Participation of PACAP in NANC relaxation was suggested only in the distal colon, while that of VIP was not detected in any of regions. Results obtained in the present study indicate that extent of participation of nitric oxide in NANC relaxation in Sprague Dawley rat intestine is more significant than those of other strains, Wistar and Wistar-ST.  相似文献   
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