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The effects of niacin deficiency on the levels of soluble proteins and enzyme activities of Japanese quail have been investigated. SDS-polyacrylamide gel electrophoresis revealed that in the pectoral muscle the soluble proteins with molecular masses corresponding to 181, 128, 93, 76, 72, 62, 56, 43, 41, 28 and 20 kDa were present in lower amounts but those of 60, 50 and 37 kDa were present in higher amounts. In the heart the soluble proteins with a molecular mass of 181 kDa were present in lower amounts and in the brain those of 43 kDa were present in lower amounts but those of 221 kDa were present in higher amounts. In the intestine the soluble proteins with molecular masses corresponding to 181, 102, 83, 74, 72, 44 and 40 kDa were present in lower amounts but those of 41 kDa and 18 kDa were present in higher amounts. There was a marked reduction in the level of NAD and NADPH in the pectoral muscle of niacin deficient quail but not in other tissues. The specific activity of glyceraldehyde-3-phosphate dehydrogenase decreased markedly both in the liver and pectoral muscle of niacin deficient quail whereas that of 6-phosphogluconate dehydrogenase and malic enzyme decreased markedly in the liver or pectoral muscle, respectively. In contrast, the specific activity of acetylcholinesterase and carboxypeptidase increased markedly in the liver or the pectoral muscle, respectively. The results suggest that a severe niacin deficiency exerted specific effects on levels of some soluble proteins particularly in the pectoral muscle and intestine and on activities of certain enzymes in the liver and the pectoral muscle. 相似文献
124.
S. C. L. Koh A. Gunasekaran S. M. Saad 《The International Journal of Advanced Manufacturing Technology》2006,31(3-4):305-315
This research has developed and implemented a part recognition and classification structure to execute parts verification in a multi-level-dependent demand manufacturing system. The part-recognition algorithm enables the parent and child relationship between parts to be recognised in a finite-capacitated manufacturing system. This algorithm was developed using the SIMAN simulation language and implemented in a multi-level-dependent demand manufacturing simulation model. The part-classification structure enables the modelling of a multi-level-dependent demand manufacturing system between parts to be carried out effectively. The part-classification structure was programmed using Visual Basic Application (VBA) and was integrated into the work-to-list generated from a simulated materials requirements planning (MRP) model. This part-classification structure was then implemented in the multi-level-dependent demand manufacturing simulation model. Two stages of implementation, namely, parameterisation and execution, of the part recognition and classification structure were carried out. A real case study was used and five detailed steps of execution were processed. Simulation experiments and MRP were run to verify and validate the part recognition and classification structure. The results led to the conclusion that implementation of the recognition and classification structure has effectively verified the correct parts and sub-assemblies used for the correct product and order. No parts nor sub-assembly shortages were found, and the quantity required was produced. The scheduled release for some orders was delayed due to overload of the required resources. When the loading is normal, all scheduled release timing is adhered to. The recognition and classification structure has a robust design; hence, it can be easily adapted to new system parameters to study different or more complex cases. 相似文献
125.
The problem of electromagnetic wave propagation in a realistic forest environment in the high-frequency and very high-frequency bands is considered. In particular, the effect of the nonplanar interface between the air and the canopy, which has been ignored in previous models, is examined. An analytical formulation is obtained for the mean field when both the transmitter and the receiver are within the foliage. This formulation is based on distorted Born approximation and accounts for the surface roughness that exists between the canopy and air interface. It is shown that the surface roughness attenuates the so-called lateral wave slightly, which is the dominant source of the field at receiver locations far from the transmitter. It is also shown that this attenuation rate increases when the RMS height of the surface roughness is increased 相似文献
126.
The system reliability of a “j or more paths required system” can be obtained from the probability that there is no minimal path suffering a short-mode failure and there is at least one set of j separate paths not suffering an open-mode failure. In order to evaluate the system reliability, we use the method of generating the sum of disjoint products, which is widely used for two-state systems. Some rules and a procedure for the minimized reliability formula are presented. 相似文献
127.
Railton C.J. Boon Ping Koh Craddock I.J. 《Antennas and Propagation, IEEE Transactions on》2004,52(11):2941-2949
In this contribution, the problem of accurately representing thin wires within the finite-difference time-domain (FDTD) mesh is addressed by means of a method based on the weighted residual (WR) interpretation of the FDTD algorithm. Results for wire dipoles and wire transmission lines, obtained using the proposed method, are presented and compared to those obtained using existing techniques. It is shown that the proposed method yields results which are more accurate and are less dependent on the choice of cell size than other approaches and, in addition, lends itself well to being extended for more complicated structures. Details of the calculation of the update equations are given. 相似文献
128.
The polysomnographic and ventilatory patterns of nine normal adults were measured during non-rapid-eye-movement (NREM) stage 2 sleep before and after repeated administrations of a tone (40-72 dB) lasting 5 s. The ventilatory response to arousal (VRA) was determined in data sections showing electrocortical arousal following the start of the tone. Mean inspiratory flow and tidal volume increased significantly above control levels in the first seven breaths after the start of arousal, with peak increases (64.2% > control) occurring on the second breath. Breath-to-breath occlusion pressure 100 ms after the start of inspiration showed significant increases only on the second and third postarousal breaths, whereas upper airway resistance declined immediately and remained below control for > or = 7 consecutive breaths. These results suggest that the first breath and latter portion of the VRA are determined more by upper airway dynamics than by changes in the neural drive to breathe. Computer model simulations comparing different VRA time courses show that sustained periodic apnea is more likely to occur when the fall in the postarousal increase in ventilation is more abrupt. 相似文献
129.
Jeongwook Koh Schmitt-Landsiedel D. Thewes R. Brederlow R. 《Solid-State Circuits, IEEE Journal of》2007,42(6):1352-1361
We present a novel principle for 1/f noise reduction in linear analog CMOS ICs. The principle is experimentally demonstrated for a two-stage CMOS Miller operational amplifier in a standard 0.12-mum, 1.5-V digital CMOS technology. A threefold 1/f noise reduction (5 dB) is achieved at 10 Hz compared with a reference circuit. The impact of the principle on the circuit performance is investigated 相似文献
130.
JS Han HC Kim JK Chung HS Kang J Donaldson JK Koh 《Canadian Metallurgical Quarterly》1998,45(6):1089-1103
Phospholipase D (PLD) has been extracted from rat brain membranes and chromatographically enriched 70-fold. From the rat brain cytosol, Cdc42 with a Mr of about 24,000 and ADP-ribosylation Factor (Arf) with a Mr of about 18,000 have been purified to near homogeneity. PLD was activated better by purified cytosolic Arf than by the other small G proteins tested. Cdc42 purified from rat brain cytosol showed 70% of PLD activation activity exerted by cytosolic Arf, suggesting that Cdc42 may be one of the major G proteins involved in the activation of membrane-associated PLD. While Cdc42 or RhoA exhibited synergistic activation of PLD when administered in conjunction with Arf, Cdc42 and RhoA showed an additive effect when used together. It is possible that Arf and Rho family proteins may have different interaction sites on PLD. These findings support a role for GTP-binding proteins of the Rho family as well as Arf in the activation of membrane-associated PLD and further suggest that Cdc42 may be a major G protein involved in the PLD activation in rat brain. 相似文献