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11.
Mi Ra Lee Jing Gang Hou Shahnaz Begum Jian Jie Xue Yun Bo Wang Chang Keun Sung 《Food science and biotechnology》2013,22(6):1747-1751
This study evaluates three edible mushrooms: Lentinus edodes, Sparassis crispa, and Mycoleptodonoides aitchisonii, in terms of acetylcholinesterase (AChE) inhibition, antioxidant potency and constituents free amino acids and mineral. The concentration of essential amino acids was found to be 34.10 mg/g in M. aitchisonii, 26.25 mg/g in S. crispa, 25.99 mg/g in L. edodes. S. crispa displayed the highest DPPH scavenging activity and phenolic contents. The best results for AChE inhibition were obtained from M. aitchisonii. These results suggest that M. aitchisonii has high potential for cognitive improvement by AChE inhibition and antioxidant potency. 相似文献
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This paper presents a two-level approach for determining the minimum cost expansion pattern (location and size) of new reactive compensation sources that would ensure steady-state secure operation of large scale power systems not only under a given set of operating conditions for the intact system, but also under contingency conditions. This preventive planning problem is decomposed into a var dispatch (Level 1) problem and a var allocation (Level 2) problem which are related together using the generalized Benders decomposition. The methodology has been implemented in a prototype computer package which can handle power systems with up to 1500 buses. Results of testing the package with practical power systems of different sizes and characteristics are presented. 相似文献
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N Begum L Ragolia J Rienzie M McCarthy N Duddy 《Canadian Metallurgical Quarterly》1998,273(39):25164-25170
In this study, we examined the regulation of mitogen-activated protein kinase phosphatase (MKP-1) expression by insulin in primary vascular smooth muscle cell cultures. Insulin caused a rapid time- and dose-dependent induction of MKP-1 mRNA and protein expression. Blockade of nitric-oxide synthase (NOS) with NG-monomethyl-L-arginine acetate, and cGMP with RpcGMP, completely inhibited MKP-1 expression. Insulin-mediated MKP-1 expression was preceded by inducible NOS (iNOS) induction and cGMP production. Blockade of phosphatidylinositol 3-kinase (PI3-kinase) signaling with wortmannin inhibited insulin-mediated iNOS protein induction, cGMP production, and MKP-1 expression. To evaluate potential interactions between NOS and the mitogen-activated protein kinase (MAPK) signaling pathways, we employed PD98059 and SB203580, two specific inhibitors of ERKs and p38 MAPK. These inhibitors abolished the effect of insulin on MKP-1 expression. Only PD98059 inhibited insulin-mediated iNOS protein induction. Vascular smooth muscle cells from spontaneous hypertensive rats exhibited a marked decrease in MKP-1 induction due to defects in insulin-induced iNOS expression because of reductions in PI3-kinase activity. Treatment with sodium nitroprusside and 8-bromo-cGMP restored MKP-1 mRNA expression to levels comparable with controls. We conclude that insulin-induced MKP-1 expression is mediated by PI3-kinase-initiated signals, leading to the induction of iNOS and elevated cGMP levels that stimulates MKP-1 expression. 相似文献
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OBJECTIVE: To identify characteristics associated with provision of bystander CPR in witnessed out-of-hospital cardiac arrest cases. METHODS: An observational, prospective, cohort study was performed using cardiac arrest cases as identified by emergency medical services (EMS) agencies in Oakland County. MI, from July 1, 1989, to December 31, 1993. All patients who sustained a witnessed arrest prior to arrival of EMS personnel were reviewed. RESULTS: Of the 927 patients meeting entry criteria, the 229 patients receiving bystander CPR were younger: 60.9 +/- 14.7 vs 67.9 +/- 14.7 years (p < 0.01). Most (76.6%) cardiac arrests occurred in the home. In a multivariate logistic model, only the location of arrest outside the home was a significant predictor of receiving bystander CPR [odds ratio (OR) 3.8; 99% CI 2.5, 5.9]. Arrests outside the home were associated with significantly improved outcome, with 18.2% of out-of-home and 8.2% of in-home victims discharged from the hospital alive (OR 2.5; 99% CI 1.4, 4.4). CONCLUSION: Patients who have had witnessed cardiac arrests outside the home are nearly 4 times more likely to receive bystander CPR, and are twice as likely to survive. This observation emphasizes the need for CPR training of family members in the authors' locale. This phenomenon may also represent a significant confounder in studies of out-of-hospital cardiac arrest and resuscitation. 相似文献
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The combustion characteristics of high-ash Bangladeshi peat was investigated in an atmospheric fluidized-bed combustor at bed temperatures of 750, 800 and 850°C. The particle size was varied from 8.05 mm to 22.76 mm. Combustion of this variety of peat occurred at constant size and thus followed a shrinking core model. Volatile evolution is complete before the particles reached bed temperature and during char combustion the particle temperature exceeded the bed temperature. Combustion times can be represented by power law equations. Results indicated that the burning rate of peat char is a combination of diffusion and kinetic control mechanisms. 相似文献
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Connie A.T. Ferdousi F. Sharmin M. Khan M.R. 《Vision, Image and Signal Processing, IEE Proceedings -》2006,153(2):95-100
A simple and efficient method for system identification even at a very low signal-to-noise ratio (SNR) is presented. At an SNR as low as -7.5 dB, noise dominates the spectrum and system poles are almost lost in the profound noise. In the proposed method, an enhanced spectrum is estimated in the discrete cosine transform (DCT) domain using the least squares curve-fitting technique. The system modes that were previously indistinguishable become prominent in the enhanced spectrum. The system order is then overestimated using least squares higher order Yule-Walker (LSHOYW) equations to obtain better accuracy. The poles having higher strength in the autocorrelation domain are then identified as system poles. 相似文献
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K. Sivaguru K.M. Meera Sheriffa Begum N. Anantharaman 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2009,155(1-2):207-214
Three-phase fluidization refers to fluidization of solid particles by co-current, upward flow of gas and liquid-phases for the purpose of bringing three-phases in contact in a single operation. Due to complications in understanding hydrodynamics of three-phase fluidized bed, CFD analysis is used to predict the hydrodynamics of it. In this study, liquid-phase is water which flows continuously, where as the gas phase is air which is distributed discretely throughout the bed. Ceramic particle of 1 mm diameter, density of 2650 kg/m3 is used as a solid phase. Excellent mixing, heat and mass transfer rates are the unique features of three-phase fluidized bed. The selection of distributor plays an important role in the quality of fluidization [1]. CFD model is created as the realistic representation of actual fluidized bed. The liquid and solid flow is represented by the mixture model. The air is injected from the bottom of the fluidized by means of discrete phase method (DPM). Simulation results are obtained by using porous jump and porous zone model to represent the distributor. It is found that porous zone model is best applicable in the industries, since stability of operating conditions is achieved even with non-uniform air, water flowrates and with different bed heights(100 mm, 200 mm, 300 mm, 400 mm and 500 mm).Simulated Pressure drop values of the fluidized bed have good agreement with the experimental findings. As the gas flowrate increases, the pressure drop in the column is decreases, provided the initial bed height, diameter of the column, and liquid flowrate are constant. This is due to decrease in density of the fluid medium in the bed by means of more gas hold up. The approach of the simulated values to the experimental values can be reduced with better understanding the nature of the fluidized bed. 相似文献
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Saba Gul Mushtaq Ahmad Muhammad Zafar Saraj Bahadur Shazia Sultana Najla Begum Syed Nasar Shah Wajid Zaman Fazal Ullah Asma Ayaz Uzma Hanif 《Microscopy research and technique》2019,82(7):1021-1031
The present study is insight into pollen morphology for characterizing species and their utility in the taxonomic separation of certain taxa of subfamily Nepetoideae (Lamiaceae) from Pakistan. The pollen micromorphology of 11 species of the Nepetoideae was analyzed and documented using light microscopy and scanning electron microscopy (SEM) for both qualitative and quantitative characteristics. Most species have hexazonocolpate pollen grains but trizonocolpate and tetrazonocolpate pollen with circular and oval amb were also rarely observed in Mentha spicata. The basic pollen shape in most of the studied species was subspheroidal but prolate grains were also observed in M. spicata, S. coccinea, and S. plebeia. The exine sculpturing of Nepetoideae pollen was taxonomically very informative particularly at subfamily level. Observations of exine sculpturing with SEM revealed various types of pollen grains: reticulate, bireticulate, microreticulate, perforate, aerolate, and gammate. The bireticulate type further subdivided into three subtypes based on the number of secondary lumina in each primary lumen and is characterized by varying characteristics of the secondary reticulum and primary muri. A significant variation was observed in colpus surface ornamentation. The maximum polar diameter was found in O. americanum (58 ± 5.8 μm) and the maximum equatorial diameter observed in O. basilicum (50.25 ± 1.37 μm). Pollen features of the studied species were discussed and compared based on the current taxonomical concepts. The results showed that pollen traits of the subfamily Nepetoideae was found significant to classify the taxa. Furthermore, pollen features provide additional evidence to distinguish macromorphologically similar taxa from each other. 相似文献
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