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71.
An alkaline trypsin was purified from the viscera of zebra blenny (Salaria basilisca) by ammonium sulphate (40?80% saturation) precipitation, Sephadex G-100, Mono Q-Sepharose and ultrafiltration. A yield of 12% with a purification-fold of 4.2 was obtained. The trypsin had an apparent molecular weight of 27 kDa. Soybean trypsin inhibitor and phenylmethylsulfonyl fluoride showed a strong inhibitory effect on the purified trypsin. Trypsin had maximal activity at pH 9.5 and 60 °C for the hydrolysis of -benzoyl-dl-arginine-p-nitroanilide (BAPNA). It was stable at low temperatures and in the pH range of 7.0?12.0. The N-terminal amino acid sequence of the first 12 amino acids of the purified protease was IVGGRECTEPSQ. S. basilisca trypsin, which showed high homology with other fish trypsins, had a charged Arg residue at position 5, where Tyr is common in marine vertebrates and mammalian trypsins. The trypsin kinetic constants, Km and kcat for BAPNA, were 0.6 mM and 1.38 s?1, respectively.  相似文献   
72.
Although conventional conveyor-based vehicle assembly systems have proved to be very efficient in terms of plant productivity, it has also been recognized as a system which puts too much pressure on people. This paper introduces an alternative to conventional conveyor-based assembly lines, one that is designed to enrich the work environment of employees without sacrificing productivity. The reforming methodology suggested here applies the idea of cell manufacturing to the conventional conveyor-based assembly line system, but it does not require making any major changes to the existing hardware configurations of the plant. Benefits of the reformed line for workers include a longer cycle time, more balanced work loads, and greater protection against developing musculoskeletal disorders. To prove the effectiveness of the suggested methodology, we built a virtual factory model and performed simulations to assess the performance of the reformed line.  相似文献   
73.
LiNi0.5Co0.5O2 cathode materials were synthesized by a solid-state reaction method at 800 °C using Li2CO3, LiOH·H2O; NiO, NiCO3; CoCO3, or Co3O4 as the sources of Li, Ni, and Co, respectively. The electrochemical properties of the synthesized samples were then investigated. The structure of the synthesized LiNi0.5Co0.5O2 was analyzed, and the microstructures of the samples were observed. The curves of voltage vs. x in LixNi0.5Co0.5O2 for first charge–discharge and intercalated and deintercalated Li quantity Δx were studied. Destruction of unstable 3b sites and phase transitions were discussed from the first and second charge–discharge curves of voltage vs. x in LixNi0.5Co0.5O2. The LiNi0.5Co0.5O2 sample synthesized from Li2CO3, NiCO3 and Co3O4 has the largest first discharge capacity (142 mAh/g). The LiNi0.5Co0.5O2 sample synthesized from Li2CO3, NiO and Co3O4 has a relatively large first discharge capacity (141 mAh/g) and the smallest capacity deterioration rate (4.6 mAh/g/cycle).  相似文献   
74.
Mice exposed to cold rely upon brown adipose tissue (BAT)-mediated nonshivering thermogenesis to generate body heat using dietary glucose and lipids from the liver and white adipose tissue. In this report, we investigate how cold exposure affects the PI3 K/Akt signaling cascade and the expression of genes involved in lipid metabolism and trafficking in BAT. Cold exposure at an early time point led to the activation of the PI3 K/Akt, insulin-like signaling cascade followed by a transient decrease in adipose triglyceride lipase (ATGL) gene and protein expression in BAT. To further investigate how cold exposure-induced signaling altered ATGL expression, cultured primary brown adipocytes were treated with the β3-adrenergic receptor (β3AR) agonist CL 316,243 (CL) resulting in activation of PI3 K/Akt, ERK 1/2, and p38 signaling pathways and significantly decreased ATGL protein levels. ATGL protein levels decreased significantly 30 min post CL treatment suggesting protein degradation. Inhibition of PKA signaling by H89 rescued ATGL levels. The effects of PKA signaling on ATGL were shown to be independent of relevant pathways downstream of PKA such as PI3 K/Akt, ERK 1/2, and p38. However, CL treatment in 3T3-L1 adipocytes did not decrease ATGL protein and mRNA expression, suggesting a distinct response in WAT to β3-adrenergic agonism. Transitory effects, possibly attributed to acute Akt activation during the early recruitment phase, were noted as well as stable changes in gene expression which may be attributed to β3-adrenergic signaling in BAT.  相似文献   
75.
In this paper, we propose a segment-based annotation tool providing appropriate interactivity between a human annotator and an automatic parser. The proposed annotation tool provides the preview of a complete sentence structure suggested by the parser, and updates the preview whenever the annotator cancels or selects each segmentation point. Thus, the annotator can select the proper sentence segments maximizing parsing accuracy and minimizing human intervention. Experimental results show that the proposed tool allows the annotator to be able to reduce human intervention by approximately 39% compared with manual annotation. Sejong Korean treebank, one of the large scale treebanks, was constructed with the proposed annotation tool.  相似文献   
76.
Abstract— An AC electric field to drive the IPS mode of a liquid‐crystal display (LCD) causes a reduction in the contrast after a long period of display operation. This phenomenon is refered to as the AC image‐sticking problem caused by long‐term driving. Thus far, there is no useful method of quantitatively evaluating AC image sticking. LCD panel products that use the IPS mode have been evaluated for a decade. In this paper, a new evaluation parameter (Δθ), which was recently proposed by Suzuki et al., is introduced. It was calculated from the slight difference in the deviation angle of LC molecules from the rubbing direction. Results from several conditions of test samples are presented in this paper as a phenomena that reflect the interaction between the surface of the PI alignment and the LC molecules. The results and discussions describe reasons for azimuthal gliding after long display operation for weak AC voltage driving. It is explained by suitably adopting the Kelvin‐Voigt model which is used to discuss the rheology of viscoelastic material. It is concluded that the surface rheology of PI alignment is one of the most important factors for the contrast reduction of the AC image‐sticking problem.  相似文献   
77.
International Journal on Software Tools for Technology Transfer - DR-BIP is an extension of the BIP component framework intended for programming reconfigurable systems encompassing various aspects...  相似文献   
78.
In this paper, we propose a feature-based Korean grammar utilizing the learned constraint rules in order to improve parsing efficiency. The proposed grammar consists of feature structures, feature operations, and constraint rules; and it has the following characteristics. First, a feature structure includes several features to express useful linguistic information for Korean parsing. Second, a feature operation generating a new feature structure is restricted to the binary-branching form which can deal with Korean properties such as variable word order and constituent ellipsis. Third, constraint rules improve efficiency by preventing feature operations from generating spurious feature structures. Moreover, these rules are learned from a Korean treebank by a decision tree learning algorithm. The experimental results show that the feature-based Korean grammar can reduce the number of candidates by a third of candidates at most and it runs 1.5 ∼ 2 times faster than a CFG on a statistical parser.  相似文献   
79.
Flat-type poly(ether sulfone) (PES) membranes for ultrafiltration were prepared by the traditional phase-inversion technique. The effects of the concentration of PES and the combination of two solvents, dichloromethane (DCM) and N-methyl-2-pyrrolidone (NMP), with differences in volatility and solvating power on membrane performance were examined in terms of pure water flux (PWF) and solute rejection (SR) against poly(ethylene glycol) (PEG, MW 20,000). Changing the thermodynamic quality of PES/NMP casting solution by combining DCM, a volatile and weak solvent, affected the PWF of the resulting membrane. The SR of PES/DCM–NMP membrane, however, was more likely dependent upon the effect of evaporating the volatile solvent from the casting solution/air interface rather than the effect of changing the thermodynamic quality of the casting solution. Combining DCM in PES/NMP casting solution transformed the fingerlike macrovoids of PES/NMP membrane prepared without DCM into the isolated macrovoids. PES/DCM–NMP membrane prepared with PVP, a water soluble poreforming agent, showed an increased PWF while maintaining SR of over 90%, even under the reduced feeding pressure of 1 kg/cm2. It is necessary to measure molecular weight cutoff of membrane for demonstrating the potential of PVP for improving the membrane permeability without losing the selectivity.© 1996 John Wiley & Sons, Inc.  相似文献   
80.
Functional properties and antioxidant activities of cuttlefish (Sepia officinalis) muscle protein hydrolysates, with different degrees of hydrolysis (DH from 7.3% to 18.8%), obtained by treatment with Bacillus mojavensis A21 alkaline proteases were investigated. Protein contents for all freeze-dried cuttlefish muscle protein hydrolysates (CMPHs) ranged from 80% to 86%. For the functional properties, hydrolysis by A21 proteases increased (p < 0.05) protein solubility to above 78% over a wide pH range (2.0–11.0). However, the interfacial activities (emulsion activity index, emulsion stability index, foaming capacity and foaming stability) decreased with the increase of the DH. All CMPHs exhibited significant metal chelating activity and DPPH free radical-scavenging activity, and inhibited linoleic acid peroxidation. Antioxidant properties of protein hydrolysates increased with protein hydrolysis and the highest activities were obtained at DH of 16%. The IC50 values for DPPH radical-scavenging and metal chelating activities were found to be 0.52 ± 0.01 mg/ml and 0.67 ± 0.13 mg/ml. The obtained results suggested that functional properties and antioxidant activities of cuttlefish muscle protein hydrolysates were influenced by the degree of hydrolysis.The composition of amino acids of undigested and hydrolyzed proteins was determined. CMPHs have a high percentage of essential amino acids such as arginine, lysine, histidine and leucine. They have a high nutritional value and could be used as supplement to poorly balanced dietary proteins.  相似文献   
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