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排序方式: 共有907条查询结果,搜索用时 31 毫秒
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Maribel Plascencia‐Jatomea Miguel A Olvera‐Novoa Jos Luis Arredondo‐Figueroa George M Hall Keiko Shirai 《Journal of the science of food and agriculture》2002,82(7):753-759
This study provides information on the use of shrimp head silage protein hydrolysate (SPH) as an alternative protein source for tilapia feeding. Six diets (28% protein, 12% lipid) were prepared where fishmeal protein was replaced at levels of 0 (control), 10, 15, 20, 25 and 30% with the hydrolysate. The diets were supplied to Nile tilapia fry (338 mg initial weight) stocked in plastic recirculating 20 l tanks (10 animals per tank), with three replicates per treatment. After an 8 week experimental period, fish fed the diets containing 10 and 15% SPH showed significantly better performance in terms of final body weight, weight gain (%), mean daily weight gain (mg day?1), specific growth ratio and feed conversion ratio than those fed the control diet (fishmeal as protein source) and higher‐SPH diets. It is concluded that shrimp head hydrolysate is a promising alternative protein source for tilapia feeding, improving growth ratio at dietary inclusion levels as high as 15%. In addition, the diets with added shrimp silage protein were well accepted by the fish, which avidly consumed the feed during the experiment. © 2002 Society of Chemical Industry 相似文献
3.
Analysis on steady-state and transient heat transfer on a flat plate at the middle of a parallel duct immersed in He II was performed for bath temperatures from 1.8 to 2.1 K at 101.3 kPa. Two-dimensional computer code named SUPER-2D developed by the authors based on the two-fluid model and the theory of mutual friction was used. Steady-state critical heat flux (CHF) and the time lag from the application of a step heat input to λ transition, that is called a lifetime, were obtained numerically for various step heat fluxes and for the channel gaps from 2 to 20 mm. Effect of the gap restriction on the CHF and the lifetime were clarified. The solutions were compared with the experimental data for the ducts with the same structures and the corresponding conditions. They agreed well with the experimental data. The heat transport mechanism in the parallel duct was clarified. 相似文献
4.
M Yaono R Hasegawa K Kato J Kimura C Lin M Tada T Shirai 《Canadian Metallurgical Quarterly》1996,98(2):145-149
We attempted to purify endogenous growth factors of chick embryonal retinal pigment epithelial cells from bovine neural retina. Ammonium sulfate precipitation, gel filtration, and anion exchange column chromatography were used. Though only partially purification, bovine retinal extract had two effects, growth and transformation, on chick embryonal pigment epithelial cells. We think that these purified factors may be novel from the estimation of their molecular weight by gel filtration. 相似文献
5.
Nobuhiro Kumada Nobuo Ozawa Nobukazu Kinomura Fumio Muto 《Materials Research Bulletin》1985,20(5):583-589
Pyrochlores of A1?xHxTaO3·nH2O (A=Na,K) were prepared under the hydrothermal conditions. The values of x for these compounds were increased from 0.3 to 0.5 for A=Na and from 0.2 to 0.5 for A=K by treatment with the distilled water. The compounds with x<0.5 were decomposed to a mixture of NaTaO3 and Na2Ta4O11 for A=Na, or to a mixture of KTaO3 and a tetragonal tungsten bronze phase, and those with x=0.5 to a single phase of A2Ta4O11 at elevated temperatures. Below the decomposition temperatures, defect pyrochlores with oxygen vacancies, , were produced. They were hygroscopic, and in the case of A=K and x=0.5 the original phase was recovered by leaving in air for several hours. 相似文献
6.
Cooperative behavior of various agents in dynamic environment 总被引:5,自引:0,他引:5
Akihide Hiura Toshiya Kuroda Nobuhiro Inuzuka Ken-ichi Itoh Masashi Yamada Hirohisa Seki Hidenori Itoh 《Computers & Industrial Engineering》1997,33(3-4):601-604
The multi-agent model is a model in which agents with limited ability cooperate each other to accomplish a goal. In this paper, we introduce a multi-agent model in which agents are created to imitate real ants. There are two different type of agents, each type of which has a particular task. We designed agents to communicate each other by using pheromone considering noise. On this model, we observed cooperative behavior of agents and evaluated conditions to make an order of behavior in the model. 相似文献
7.
Okamura M. Kimura K. Shirai S. Yamauchi N. 《Electron Devices, IEEE Transactions on》1994,41(2):180-185
A light-transmitting two-dimensional photodetector array (32×32 cells) using amorphous silicon (a-Si) pin photodiodes and polysilicon (poly-Si) thin film transistors (TFT's) integrated on a transparent substrate has been developed for use in a free-space optical switching network. The fabrication and the characteristics of the photodetector array are discussed. With driving circuits and sensing amplifiers, this photodetector array shows a minimum detectable power of -25 dBm and an insertion loss of 0.4 dB for an incident optical beam with a diameter of 550 μm. By monitoring the positions and the states of input optical beams, this photodetector array can be used to control the optical paths in photonic switching systems, such as a 1024-input-port optical concentrator 相似文献
8.
S Kozlowski M Corr M Shirai LF Boyd CD Pendleton JA Berzofsky DH Margulies 《Canadian Metallurgical Quarterly》1993,151(8):4033-4044
T cell stimulation by certain class I-restricted antigenic peptides, such as the HIV 1 gp160-derived peptide, P18, requires peptide processing by angiotensin-1 converting enzyme (ACE) in FCS. We observed that longer versions of P18 and the murine cytomegalovirus pp89-derived core peptide, pMCMV, which could stimulate T cell hybridomas in FCS, were not as sensitive to the ACE inhibitor captopril as P18. Using cell-free soluble murine class I MHC molecules and protease inhibitors, we found that there are pathways of differing efficiency that use enzymes other than ACE for the proteolytic processing of peptides in serum. The kinetics of the generation of T cell stimulatory activity among P18 variant peptides in serum differed with peptide length, and with the nature of amino and COOH-terminal extensions. Such processing occurs in human plasma as well as in FCS. The understanding of this processing, its kinetics, and its inhibitors can lead to better design of peptide-based therapies, including vaccines. 相似文献
9.
Shionyu-Mitsuyama Clara; Shirai Tsuyoshi; Ishida Hirokazu; Yamane Takashi 《Protein engineering, design & selection : PEDS》2003,16(7):467-478
A computer program system was developed to predict carbohydrate-bindingsites on three-dimensional (3D) protein structures. The programssearch for binding sites by referring to the empirical rulesderived from the known 3D structures of carbohydrateproteincomplexes. A total of 80 non-redundant carbohydrateproteincomplex structures were selected from the Protein Data Bankfor the empirical rule construction. The performance of theprediction system was tested on 50 known complex structuresto determine whether the system could detect the known bindingsites. The known monosaccharide-binding sites were detectedamong the best three predictions in 59% of the cases, whichcovered 69% of the polysaccharide-binding sites in the targetproteins, when the performance was evaluated by the overlapbetween residue patches of predicted and known binding sites. Received April 24, 2003; revised June 2, 2003; accepted June 10, 2003. 相似文献
10.