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991.
A laser measuring instrument was installed in a computerized numerically controlled (CNC) router, and an automatic measurement
system, which was developed in a previous study, was used to automatically measure the cutting edge profile of throw-away
type straight bits without stopping the CNC router. In addition to the above-mentioned system, in this study, an adaptive
control program based on experimental data was installed, and an adaptive control grooving system that improved machining
accuracy and controlled the burr formation corresponding to the progression of tool wear under processing was developed. Verification
experiments of this system were carried out. The main results obtained are summarized as follows: (1) the between-process
method was adopted for this system, and three types of processing methods (type 1, 2, 3), which consisted of a combination
of an up-milling surface and a down-milling surface after processing, were investigated; (2) from the results of verification
experiments, type 2 and type 3 methods showed remarkable ability to improve the machining accuracy and control the burr formation;
and (3) it was found that the system employing adaptive control processing corresponding to the progression of tool wear in
grooving is very effective.
Part of this article was presented at the 52nd Annual Meeting of the Japan Wood Research Society, Gifu, April 2002 相似文献
992.
Nobuhito Mitani Ryoji Matsumoto Terutaka Yoshioka Takeshi Kuniga 《Scientia Horticulturae》2008,116(4):452-455
The long juvenile period of citrus seedlings before flowering is one of the major obstacles in citrus breeding. Under the citrus breeding program of National Institute of Fruit Tree Science in Japan, 299 citrus hybrid seedlings were grafted onto shiikuwasha (Citrus depressa HAYATA) and cultivated. Approximately one-third of the plants flowered two and a half years after grafting. The average length of the main stems of flowering plants was 308 cm, while that of non-flowering plants was 264 cm. Half of the plants having main stem length ≥300 cm formed flowers, while most of the plants having main stem length <210 cm formed no flower. These results indicate that plant vigor influences the flowering and that grafting effectively accelerated flowering. The proportion of flowering plants varied among cross combinations, ranging from 71.4% to 8.0% among the 10 cross combinations used. 相似文献
993.
Takashi Hamabata Toshio Sato Eiji Takita Takeshi Matsui Taishi Imaoka Nobuo Nakanishi Keizo Nakayama Takamitsu Tsukahara Kazutoshi Sawada 《Animal Science Journal》2019,90(11):1460-1467
Porcine edema disease (ED) is a toxemia that is caused by enteric infection with Shiga toxin 2e (Stx2e)‐producing Escherichia coli (STEC) and is associated with high mortality. Since ED occurs most frequently during the weaning period, preweaning vaccination of newborn piglets is required. We developed stx2eB‐transgenic lettuce as an oral vaccine candidate against ED and examined its protective efficacy using a piglet STEC infection model. Two serially developed Stx2eB‐lettuce strains, 2BN containing ingredient Stx2eB constituting a concentration level of 0.53 mg Stx2eB/g of powdered lettuce dry weight (DW) and 2BH containing ingredient Stx2eB constituting a concentration level of 2.3 mg of Stx2eB/g of powdered lettuce DW, were evaluated in three sequential experiments. Taken the results together, oral administration of Stx2eB‐lettuce vaccine was suggested to relieve the pathogenic symptoms of ED in piglets challenged with virulent STEC strain. Our data suggested that Stx2eB‐lettuce is a promising first oral vaccine candidate against ED. 相似文献
994.
Hiroyuki Sato Makoto Miura Takeshi Fujieda Masaaki Toyomizu 《Animal Science Journal》2019,90(9):1270-1277
The slope‐ratio assay for rat was used to determine whether tryptophan (Trp) availability in soybean meal (SBM) is affected by the presence of other amino acids (AAs). In a preliminary study, rats were fed graded levels of Trp‐supplemented diets to establish the Trp concentration range over which the weight gain response was linear. This range was found to be from 0.04% to 0.12% Trp. Subsequently, rats were fed basal (0.045% Trp) or Trp‐supplemented diets from three different sources: l ‐Trp alone, SBM, or l ‐Trp mixed with other AAs to reflect AA levels in the test SBM (AA‐mix). Weight gain in rats increased linearly with supplemental Trp intake (p < .05) for all Trp sources. Compared to the slope achieved with l ‐Trp alone, the estimated availability of Trp in SBM was 84.4%, while for the AA‐mix it was 93.4%. It is evident that the 6.6% reduction in l ‐Trp availability in AA‐mix is due to metabolic costs derived from excess levels of other AAs beside Trp, given that the absorption of crystalline l ‐Trp in the small intestine is 100%. In conclusion, the Trp availability of SBM was estimated to be around 90.4% (i.e., 84.4/93.4 × 100) after correcting for the effects of the other AAs in SBM. 相似文献
995.
Haoming Wu Qui D. Nguyen Tu T. M. Tran Minh T. Tang Takeshi Tsuruta Naoki Nishino 《Animal Science Journal》2019,90(3):445-452
Microbiota of the gut, milk, and cowshed environment were examined at two dairy farms managed by automatic milking systems (AMS). Feed, rumen fluid, feces, milk, bedding, water, and airborne dust were collected and the microbiota on each was assessed by Illumina MiSeq sequencing. The most abundant taxa in feed, rumen fluid, feces, bedding, and water were Lactobacillaceae, Prevotellaceae, Ruminococcaceae, Ruminococcaceae, and Lactobacillaceae, respectively, at both farms. Aerococcaceae was the most abundant taxon in milk and airborne dust microbiota at farm 1, and Staphylococcaceae and Lactobacillaceae were the most abundant taxa in milk and airborne dust microbiota at farm 2. The three most prevalent taxa (Aerococcaceae, Staphylococcaceae, and Ruminococcaceae at farm 1 and Staphylococcaceae, Lactobacillaceae, and Ruminococcaceae at farm 2) were shared between milk and airborne dust microbiota. Indeed, SourceTracker indicated that milk microbiota was related with airborne dust microbiota. Meanwhile, hierarchical clustering and canonical analysis of principal coordinates demonstrated that the milk microbiota was associated with the bedding microbiota but clearly separated from feed, rumen fluid, feces, and water microbiota. Although our findings were derived from only two case studies, the importance of cowshed management for milk quality control and mastitis prevention was emphasized at farms managed by AMS. 相似文献
996.
Teruaki Tozaki Takeshi Miyake Mio Kikuchi Hironaga Kakoi Kei‐ichi Hirota Kanichi Kusano Yuhiro Ishikawa Motoi Nomura Asuka Kushiro Shun‐ichi Nagata 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(3):199-204
Thoroughbred racehorses are produced by mating small numbers of Arabian stallions and native British mares, and have been improved by selection of horseracing performance for about 300 years. While these improvements led to good performance as racehorses, they exposed horses to numerous medical disorders, aggravated by extensive exercise. Fractures are frequent medical disorders in Thoroughbred racehorses. In this study, fracture heritability was estimated using 3,927 Japanese Thoroughbred racehorses to elucidate the risk of racehorse fractures. The heritability estimates of all examined fractures were low (h2 = 0.06), while those of fractures in carpal bone and carpus (carpal bone plus distal radius) were moderate (h2 = 0.37, 0.24, respectively). Fracture occurrence age for carpal bone and distal radius was both 3.3 years old and was younger than that for other fractures. These results indicated that a larger proportion of the variation in the studied population was due to genetic factors for carpal fractures than for other fractures, while the fractures at other bones were largely affected by environmental factors, correlated with the athlete period (number year in racing). These findings contribute to develop a management plan for suppressing racehorse fractures and improving horseracing safety. 相似文献
997.
Aisaku Arakawa Masaaki Taniguchi Takeshi Hayashi Satoshi Mikawa 《Animal Science Journal》2016,87(7):863-872
We developed a Bayesian analysis approach by using a variational inference method, a so‐called variational Bayesian method, to determine the posterior distributions of variance components. This variational Bayesian method and an alternative Bayesian method using Gibbs sampling were compared in estimating genetic and residual variance components from both simulated data and publically available real pig data. In the simulated data set, we observed strong bias toward overestimation of genetic variance for the variational Bayesian method in the case of low heritability and low population size, and less bias was detected with larger population sizes in both methods examined. The differences in the estimates of variance components between the variational Bayesian and the Gibbs sampling were not found in the real pig data. However, the posterior distributions of the variance components obtained with the variational Bayesian method had shorter tails than those obtained with the Gibbs sampling. Consequently, the posterior standard deviations of the genetic and residual variances of the variational Bayesian method were lower than those of the method using Gibbs sampling. The computing time required was much shorter with the variational Bayesian method than with the method using Gibbs sampling. 相似文献
998.
A comparison of plasma glucose and oxidative status in lactating dairy cows in summer and autumn
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Yuzo Kurokawa Rina Yamashita Miki Okita Rena Yoshitoshi Toshihisa Sugino Taketo Obitsu Kensuke Kawamura 《Animal Science Journal》2016,87(10):1212-1217
The objective of this study was to investigate the effects of the hot summer season on plasma glucose and oxidative stress markers. For two 14‐day experimental periods, namely periods 1 (July‐August) and 2 (October‐November), 12 and 14 lactating dairy cows, respectively, that were milked using an automatic milking system, were fed diets containing similar ingredients, and their milk production, plasma metabolites and oxidative status markers were investigated. Dry matter intake and milk yield were not affected by the experimental period. Rectal temperature at 18.00 hours and milk protein concentration in period 1 were higher and lower, respectively, than in period 2 (P < 0.05), suggesting that the hot summer season had an effect on the experimental dairy cows. Plasma glucose and the ascorbic acid + dehydroascorbic acid (AA) concentrations in period 1 were lower than in period 2 (P < 0.01). The plasma malondialdehyde (MDA) concentration did not differ between the experimental periods. The increase in the cellular AA uptake in peripheral tissues in period 1 might be a possible compensatory mechanism to balance the occurrence of reactive oxygen species and the antioxidant capacity in the cells, resulting in the absence of an effect of the hot summer season on plasma MDA concentration. © 2016 Japanese Society of Animal Science 相似文献
999.
Hidehisa Kawamura Nobuaki Matsuoka Shinji Tawaki Noriyuki Momoshima 《Water, air, and soil pollution》2001,130(1-4):1775-1780
Atmospheric sulfur oxides, particulate matter and deposits (wet and dry deposits) were collected from July 1998 to June 1999 at Kyushu Island, Japan. The isotopic composition of sulfur (δ34S) was measured to identify the source of sulfur in the samples. The monthly δ34S values were always low in the order of the sulfur oxides, sulfate in particulate matter and deposits. The δ34S values of the sulfur oxides ranged from ?2.7 ‰ to ?0.4 ‰ and were close to those of fossil fuels used in Japan. The δ34S values of sulfate in the particulate matter and deposits correlated with seasalt contribution, so that the δ34Snss value was calculated for non-seasalt sulfate. The δ34Snss values of sulfate in the particulate matter and deposits trended higher in winter than summer, suggesting the possibility of isotopic fractionation during chemical transformation (SO2 to SO4 2?) and of contribution of sulfate derived from sulfur sources with higher δ34S values. 相似文献
1000.
Nihei K Hanke FJ Asaka Y Matsumoto T Kubo I 《Journal of agricultural and food chemistry》2002,50(18):5048-5052
A novel A-seco limonoid was isolated from methanolic extract of Croton jatrophoides and designated as zumsin. This compound showed potent antifeedant activity against two lepidopteran larvae, pink bollworm, Pectinophora gossypiella (PC(50) = 1 microg/cm(2), PC(95) = 8 microg/cm(2)), and fall armyworm, Spodoptera frugiperda (PC(50) = 2 microg/cm(2), PC(95) = 16 microg/cm(2)). The structure of zumsin was determined as 1 using a variety of spectroscopic methods including nuclear magnetic resonance, mass spectrometry, and circular dichroism. The structure consists of an A'-B trans-fused ring while dumsin (2), a constituent of the same source, maintains an A'-B cis-fused ring, and suggests two unique biosynthetic processes after A ring oxidative expansion. 相似文献