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171.
Okumu Gordon Wanyama Kei Sawata Takuro Hirai Akio Koizumi Yoshihisa Sasaki 《Journal of Wood Science》2012,58(1):9-19
An experimental study on combined steel-to-timber joints with nails and bolts is conducted in this study. Principal results
are as follows: The initial stiffness and effective allowable resistance of combined joints depend obviously on clearances
in predrilled bolt-holes. The combined joints with nails and bolts have high potential of energy capacity to resist strong
earthquake forces. There are upper limits of clearances in predrilled bolt-holes that allow advantages of considering the
synthetic resistance of combined joints in practical structural design. Combining the joint components with appropriate design
will give higher performance against strong earthquakes increasing the safety margin and energy capacity until the failure.
The combined joints should be designed under the restrictions of particular specifications in closed design systems because
the advantages of combining the joint components are influenced obviously by various actual conditions, which are too difficult
to consider in detail in open design systems. 相似文献
172.
Konosuke OTOMARU Kenta WATAYA Takehiko UTO Kei KASAI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):301-303
To obtain blood biochemical basic data of Japanese Black calves in Kagoshima Prefecture, Japan, blood samples
were obtained from 582 clinically healthy calves on 27 farms. Calves were divided into three stages: the
suckling stage (between 14 and 90 days of age, n=191), the early growing stage (between 91 and 180 days of
age, n=200) and the late growing stage (between 181 and 270 days of age, n=191). The mean concentration of
total cholesterol, triglyceride, nonesterified fatty acids, calcium and zinc, and the mean activities of
γ-glutamyltransferase and alkaine phospatase in the suckling stage were significantly higher than those in the
early and late growing stages (P<0.01). The mean concentration of total protein, albumin
and globulin increased gradually with growing. The mean concentration of beta-hydroxybutyrate in the suckling
stage was below 150 µmol/l, however, it elevated above 400
µmol/l in the early and late growing stages. The mean concentration of
copper concentration was above 70 µg/dl in all stages. The mean
concentration of zinc was between 90 and 110 µg/dl in all stages. These
results suggest that the blood biochemical values of Japanese Black calves vary with growing stages, and the
blood parameters obtained in this study are considered useful as indices for health management of Japanese
Black calves. 相似文献
173.
Sri Hartati Enny Sudarmonowati Tomomi Kaku Hisato Ikegaya Rumi Kaida Kei’ichi Baba Takahisa Hayashi 《Journal of Wood Science》2011,57(6):463-469
Transgenic mangium trees (Acacia mangium) overexpressing xyloglucanase (AaXEG2) were generated by spraying flower buds with Agrobacterium solution and allowing seeds to develop. The overexpression of xyloglucanase decreased xyloglucan content in the cell walls
and increased stem length and diameter. The leaves of the transgenic seedlings exhibited accelerated heteroblastic development,
proceeding from the stage of three bipinnate leaves to that of enlarging petiole 2 weeks earlier than wild type seedlings
did. 相似文献
174.
Inaba Y Aikawa Y Hirai T Hashiyada Y Yamanouchi T Misumi K Ohtake M Somfai T Kobayashi S Saito N Matoba S Konishi K Imai K 《The Journal of reproduction and development》2011,57(4):437-443
The aim of this study was to develop an in-straw dilution method suitable for 1-step bovine embryo transfer of vitrified embryos using the Cryotop vitrification-straw dilution (CVSD) method. The development of embryos vitrified using the CVSD method was compared with those of embryos cryopreserved using in-straw vitrification-dilution (ISVD) and conventional slow freezing, outside dilution of straw (SFODS) methods. In Experiment 1, in vitro-produced (IVP) embryos cryopreserved using the CVSD method were diluted, warmed and exposed to the dilution solution at various times. When vitrified IVP embryos were exposed to the dilution solution for 30 min after warming, the rates of embryos developing to the hatched blastocyst stage after 72 h of culture (62.0-72.5%) were significantly lower (P<0.05) than those of embryos exposed to the solution for 5 and 10 min (82.4-94.3%), irrespective of supplementation with 0.3 M sucrose in the dilution solution. In Experiment 2, the rate of embryos developing to the hatching blastocyst stage after 48 h of culture in IVP embryos cryopreserved using the SFODS method (75.0%) was significantly (P<0.05) lower than those of embryos cryopreserved using the CVSD and ISVD methods (93.2 and 97.3%, respectively). In Experiment 3, when in vivo-produced embryos that had been cryopreserved using the CVSD, ISVD and SFODS methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception and delivery rates among groups. In Experiment 4, when IVP embryos derived from oocytes collected by ovum pick-up that had been cryopreserved using the CVSD and ISVD methods and fresh embryos were transferred to recipient animals, no significant differences were observed in the conception rates among groups. Our results indicate that this simplified regimen of warming and diluting Cryotop-vitrified embryos may enable 1-step bovine embryo transfer without the requirement of a microscope or other laboratory equipment. 相似文献
175.
Q969R polymorphism in NLRP3 is associated with immune responses to vaccination against bacterial infections in pigs 下载免费PDF全文
Hiroki Shinkai Kei Terada Daisuke Toki Masanori Tohno Hirohide Uenishi 《Animal Science Journal》2018,89(8):1043-1050
Nucleotide‐binding domain, leucine‐rich‐containing family, pyrin‐domain containing‐3 (NLRP3) is an important pattern recognition receptor involved in various inflammatory responses and adjuvant effects upon vaccination. We previously identified the Q969R (A2906G) gain‐of‐function polymorphism in porcine NLRP3, which increased production of interleukin‐1β in in vitro gene transfection experiments. Here, we explored the associations between the A2906G polymorphism and antibody responses after vaccination against bacteria in Large White pigs maintained under specific pathogen‐free conditions. The NLRP3‐2906A/G pigs had a greater antibody response to vaccine antigens than NLRP3‐2906A/A pigs. We observed a significant association of the antibody response against Haemophilus parasuis serotype 2 and 5 with NLRP3 genotypes. As the A2906G polymorphism in NLRP3 is widely distributed in commercial pig breeds, Landrace, Large White and Berkshire pigs, there is potential for improvement in vaccine efficiency and disease resistance using this polymorphism in various pig populations. 相似文献
176.
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
177.
Viju V. Pillai Tiffany G. Kei Shannon E. Reddy Moubani Das Christian Abratte Soon H. Cheong Vimal Selvaraj 《Animal Science Journal》2019,90(9):1149-1160
Mechanisms that direct reprogramming of differentiated somatic cells to induced pluripotent stem cells (iPSCs), albeit incomplete in understanding, are highly conserved across all mammalian species studied. Equally, proof of principle that iPSCs can be derived from domestic cattle has been reported in several publications. In our efforts to derive and study bovine iPSCs, we encountered inadequacy of methods to generate, sustain, and characterize these cells. Our results suggest that iPSC protocols optimized for mouse and human somatic cells do not effectively translate to bovine somatic cells, which show some refractoriness to reprogramming that also affects sustenance. Moreover, methods that enhance reprogramming efficiency in mouse and human cells had no effect on improving bovine cell reprogramming. Although use of retroviral vectors coding for bovine OCT4, SOX2, KLF4, cMYC, and NANOG appeared to produce consistent iPSC‐like cells from both fibroblasts and cells from the Wharton's jelly, these colonies could not be sustained. Use of bovine genes could successfully reprogram both mouse and human cells. These findings indicated either incomplete reprogramming and/or discordant/inadequate culture conditions for bovine pluripotent stem cells. Therefore, additional studies that advance core knowledge of bovine pluripotency are necessary before any anticipated iPSC‐driven bovine technologies can be realized. 相似文献
178.
Kei Asada Taku Nishimura Chihiro Kato Koki Toyota Masaaki Hosomi 《Paddy and Water Environment》2013,11(1-4):559-571
Soil and water pollution caused by organic waste is a concern for livestock-breeding areas. Nitrogen balance in a paddy-field water-purifying system in which cattle feces were applied was studied for 4 years to assess the suitability of the system for a subtropical area, Japan. Three successive harvestings using ratoon of forage rice following one rice transplanting were conducted with chemical fertilizer and high and low rates of cattle-feces application. Nitrogen load was 81.3–495.0 kg N ha?1 year?1, while nitrogen uptake was highly dependent on the yield of the first harvesting. Annual variation of forage rice yields was large, ranging from 15.5 to 26.8 Mg ha?1 owing to fluctuation in the yield at second and later harvestings. On average, nitrogen was lost by leaching at a rate of 2.3–3.4 kg N ha?1 year?1. The nitrogen content in soil at a depth of 0–5 cm increased up to 12.2 kg N ha?1 over the 4-year period compared with that before the field experiment. However, continuous application of cattle feces could slightly increase the nitrogen content in soil at a depth greater than 35 cm. Our results showed the ability of flooded forage rice to remove nitrogen at up to 320.1 kg ha?1 year?1 for a field to which cattle feces were applied. Further investigation is needed to produce a high and stable yield at second harvesting each year, to prevent the accumulation of soil nitrogen, and to assess gaseous nitrogen loss. 相似文献
179.
Biomechanical Comparison of Locking Compression Plate versus Positive Profile Pins and Polymethylmethacrylate for Stabilization of the Canine Lumbar Vertebrae 下载免费PDF全文
180.
Kanchana PUNYAWAI Nitira ANAKKUL Kanokwan SRIRATTANA Yoshio AIKAWA Siwat SANGSRITAVONG Takashi NAGAI Kei IMAI Rangsun PARNPAI 《The Journal of reproduction and development》2015,61(5):431-437
This study was designed to compare the efficiency of the Cryotop method and that of two methods that employ a micro volume air cooling (MVAC) device by analyzing the survival and development of bovine oocytes and blastocysts vitrified using each method. In experiment I, in vitro-matured (IVM) oocytes were vitrified using an MVAC device without direct contact with liquid nitrogen (LN2; MVAC group) or directly plunged into LN2 (MVAC in LN2 group). A third group of IVM oocytes was vitrified using a Cryotop device (Cryotop group). After warming, vitrified oocytes were fertilized in vitro. There were no significant differences in cleavage and blastocyst formation rates among the three vitrified groups, with the rates ranging from 53.1% to 56.6% and 20.0% to 25.5%, respectively; however, the rates were significantly lower (P < 0.05) than those of the fresh control group (89.3% and 43.3%, respectively) and the
solution control group (87.3% and 42.0%, respectively). In experiment II, in vitro-produced (IVP) expanded blastocysts were vitrified using the MVAC, MVAC in LN2 and Cryotop methods, warmed and cultured for survival analysis and then compared with the solution control group. The rate of development of vitrified-warmed expanded blastocysts to the hatched blastocyst stage after 24 h of culture was lower in the MVAC in LN2 group than in the solution control group; however, after 48–72 h of culture, the rates did not significantly differ between the groups. These results indicate that the MVAC method without direct LN2 contact is as effective as the standard Cryotop method for vitrification of bovine IVM oocytes and IVP expanded blastocysts. 相似文献