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101.
102.
The effect of addition of pregastric lipase enzyme on the accelerated ripening of white pickled cheese was investigated. Commercial pregastric lipase was added to milk before rennet addition at a level of 0,5, 8, 11 g per 100 L of milk and cheeses were made from this milk. Total solids, fat, total nitrogen, salt, titratable acidity, pH and free fatty acids (C2 -C18:1 ) were analysed in the samples during 1–90 days of ripening period at 15 days intervals. Total solids, fat, total nitrogen, salt, titratable acidity, and pH of cheeses slightly increased during the ripening period. Free fatty acids and volatile free fatty acid contents in cheeses made from pregastric lipase added milk were affected by pregastric lipase and their contents were increased significantly (P<0.01) during the ripening period. Particularly, when cheese had a high level (11 g per 100 L milk) pregastric lipase, the amounts of butyric, caproic and caprylic acids in white pickled cheese were quite high. The relative amounts of volatile free fatty acids varied with storage time and pregastric lipase levels. 相似文献
103.
Mangalvedekar H.A. Paithankar A.S. Chakravarthy D.P. Dixit K.P. Barve D.N. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2009,16(4):1006-1010
This paper discusses the experiments conducted for the development of 50 kV, 10 A, 10 μs duration, and rise time of 2 μs solid state pulse power modulator using toroidal amorphous steel core and low cost IGBT switches. The experiments revealed (i) the need for new design methodologies based on energy transfer between the electrical and magnetic systems and (ii) the success of low-cost switching circuit. 相似文献
104.
P. Negi G. Dixit H. M. Agrawal R. C. Srivastava 《Journal of Superconductivity and Novel Magnetism》2013,26(5):1611-1615
The structural, optical, and magnetic properties of multiferroic GdMnO3 nanoparticles synthesized by the modified sol–gel route have been investigated. Raman spectroscopy and X-ray diffraction along with Rietveld refinement confirm the pure phase of the GdMnO3 nanoparticles having an orthorhombic perovskite (space group: Pnma) type structure. The morphology was examined by scanning electron microscopy. Energy dispersive spectroscopy confirms the stoichiometry of the composition. The room temperature UV-visible absorption spectrum using Tauc’s relation gives an optical band gap of ~2.9 eV. A magnetization study of the GdMnO3 nanoparticles was performed over a temperature range of 2–300 K at an applied field of 0.05 T by using a vibrating sample magnetometer. An effective magnetic moment (μ eff) of ~9.2μ B was obtained. The system is paramagnetic at room temperature and shows a ferromagnetic-like nature at 2 K as the applied magnetic field aligns the Gd moments and the contribution of the net moment of Gd spins is larger than that of the anti-ferromagnetically canted state of the Mn spins. 相似文献
105.
Assi Chadi Shami Abdallah Ali M. A. Ye Yinghua Dixit Sudhir 《Photonic Network Communications》2002,4(3-4):377-390
This work focuses on developing and implementing comprehensive unified constraint-based routing algorithms within the generalized multi-protocol label switching framework (GMPLS) to provision sub-wavelength circuits (low-rate traffic streams). Constraint-based routing is further augmented in this work by dynamically routing both an active and another alternate link/node-disjoint backup path at the same time in order to provision a given connection request. This new integrated approach combines both IP routing and optical resource allocation to setup end-to-end connections. 相似文献
106.
In the present work, a knowledge-based system is developed for the prediction of surface roughness in turning process. Neural networks and fuzzy set theory are used for this purpose. Knowledge acquired from the shop floor is used to train the neural network. The trained network provides a number of data sets, which are fed to a fuzzy-set-based rule generation module. A large number of IF–THEN rules are generated, which can be reduced to a smaller set of rules by using Boolean operations. The developed rule base may be used for predicting surface roughness for given process variables as well as for the prediction of process variables for a given surface roughness. The concise set of rules helps the user in understanding the behavior of the cutting process and to assess the effectiveness of the model. The performance of the developed knowledge-based system is studied with the experimental data of dry and wet turning of mild steel with HSS and carbide tools. 相似文献
107.
Neurofibromatosis type 2 (NF2) is a dominantly inherited disorder characterized by the occurrence of bilateral acoustic neuromas (ANs and other central nervous system tumors. Magnetic resonance images and audiologic data on 22 patients with NF2 who underwent multiple studies at the National Institutes of Health between 1983 and 1993 were reviewed to determine the growth characteristics of ANs in these patients. The average growth rate of ANs in NF2 patients was 0.30 cm3 per year and was significantly higher in older patients (0.75 cm3 per year) than in younger ones (0.12 cm3 per year). Larger ANs were more commonly found in patients with concomitant spinal tumors or meningiomas. NF2 patients with spinal tumors but not meningiomas demonstrated faster growth rates than patients without additional tumor burden. The data from this study suggest that older patients or patients with associated spinal tumors have faster growing ANs and therefore should be followed closely and treated aggressively. 相似文献
108.
109.
SE Santos AK Ribeiro-Dos-Santos JF Guerreiro EJ Santos TA Weimer SM Callegari-Jacques MA Mestriner MH Franco MH Hutz FM Salzano 《Canadian Metallurgical Quarterly》1998,25(6):505-522
A total of 732 individuals affiliated with six Amazonian Indian populations were variously studied in relation to 26 protein genetic systems. Eleven of them were found to be monomorphic in these groups, in accordance with previous investigations. Similarities and dissimilarities (the latter involving the Rh, Duffy, haptoglobin and transferrin systems) were observed in relation to earlier investigations in four of these populations (Galibi, Palikour, Mundurucu and Tenharim). A dimeric, cathodal variant of albumin was found among two Galibi subjects, and the fairly common occurrence of CP* ACAY among some South American Indian populations was confirmed. The results in the six populations were compared with those from 29 others. When relationships are searched for among tribes of the same linguistic group, the factor that seems to be most influential is geographical localization, an exception being the pattern observed among the Cayapo subgroups. The latter shows genetic differences of the same level of magnitude as those observed among Ge-speaking tribes. 相似文献
110.
Cleavage motifs of the yeast 20S proteasome beta subunits deduced from digests of enolase 1 总被引:3,自引:0,他引:3
AK Nussbaum TP Dick W Keilholz M Schirle S Stevanovi? K Dietz W Heinemeyer M Groll DH Wolf R Huber HG Rammensee H Schild 《Canadian Metallurgical Quarterly》1998,95(21):12504-12509
The 436-amino acid protein enolase 1 from yeast was degraded in vitro by purified wild-type and mutant yeast 20S proteasome particles. Analysis of the cleavage products at different times revealed a processive degradation mechanism and a length distribution of fragments ranging from 3 to 25 amino acids with an average length of 7 to 8 amino acids. Surprisingly, the average fragment length was very similar between wild-type and mutant 20S proteasomes with reduced numbers of active sites. This implies that the fragment length is not influenced by the distance between the active sites, as previously postulated. A detailed analysis of the cleavages also allowed the identification of certain amino acid characteristics in positions flanking the cleavage site that guide the selection of the P1 residues by the three active beta subunits. Because yeast and mammalian proteasomes are highly homologous, similar cleavage motifs might be used by mammalian proteasomes. Therefore, our data provide a basis for predicting proteasomal degradation products from which peptides are sampled by major histocompatibility complex class I molecules for presentation to cytotoxic T cells. 相似文献