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排序方式: 共有229条查询结果,搜索用时 454 毫秒
41.
Zhihua Pang Hilton Deeth Hongshun Yang Sangeeta Prakash Nidhi Bansal 《Journal of dairy science》2017,100(5):3436-3447
Tilapia skin gelatin (TSG) was studied in a 3-stage process (cooling, annealing, and heating) for pure gelatin gels and in a 4-stage process (acidification, cooling, annealing, and heating) for acid milk gels and cultured yogurt. The aim was to evaluate the use of TSG as a replacement for mammalian gelatin in yogurt. In pure TSG gels, stronger gels with higher melting temperatures were formed with increasing TSG concentrations. Compared with bovine gelatin (BG), which gelled at a concentration of 2.5%, TSG gels had lower gelling (14.1°C) and melting (24°C) temperatures but comparable storage moduli during annealing. In acid milk gels, addition of TSG increased the firmness of the gels with increasing concentration. Gelling and melting points of TSG in milk gels were observed at sufficient concentrations during cooling and heating. Strands and sheets were observed in the electron micrographs of milk gels with 1% TSG and a very dense structure was observed with 2.5% TSG. Yogurt with 0.4% TSG had similar viscosity, consistency, pseudoplasticity, and thixotropy as yogurt containing 0.4% BG; no difference was perceived by sensory panelists according to a triangle test. Addition of 0.4% TSG completely prevented whey separation from the acid milk gel and yogurt. The results suggest that TSG could be a suitable replacement for mammalian gelatin in low-fat stirred yogurt. 相似文献
42.
43.
It was aimed to explore the potential of abrasives in nanometer size in friction materials (FMs). Hence six FMs were developed using micro and nano-abrasives of three types viz. alumina, SiC and silica (2%). The nano and micro composites were developed and characterized for various physical and chemical properties. The tribological performance was evaluated on a reduced scale prototype under various operating parameters and output parameters such as wear, μavg as a function of speed and pressure, load-speed sensitivity of μ and friction stability were considered to compare the performance of nano and micro-composites (NCs and MCs). It was concluded that all performance parameters were significantly and beneficially affected due to nano-fillers. Nano-silica proved to impart highest wear resistance followed by SiC and then alumina while best combination of friction properties was exhibited by composites with SiC followed by Alumina and then silica. SEM on worn surfaces of pads and discs was done to understand wear mechanism and it was clearly observed that thin coherent film on both the surfaces in case of NCs was responsible for enhanced performance. 相似文献
44.
Foamability and foam stability of dairy-based emulsions, as a function of emulsion droplet size ranging from micron- to nanometre-scale, were investigated. Fat phase (10 % w/w of anhydrous milk fat, stearin or olein fraction) was mixed with 2 % w/w protein solution (sodium caseinate or whey protein concentrate) and homogenised at 3, 10 and 35 MPa to obtain emulsions having particle sizes of about 1.20, 0.60 and 0.20 μm, respectively. The emulsions were cooled down and aged at 4 °C for 48 h to promote crystallisation. No fat coalescence was observed in any of the emulsions, as particle size distribution remained the same upon aging and whipping. It was shown that the smaller the particle size, the higher was the apparent viscosity and the lower was the solid fat content. Higher solid fat content tended to yield better foamability and foam stability. Destabilisation of air cells happened fastest with nanosized fat particles, resulting in shorter half-life of foam. 相似文献
45.
Bhanu Priya Kilari Priti Mudgil Sheikh Azimullah Nidhi Bansal Shreesh Ojha Sajid Maqsood 《Journal of dairy science》2021,104(2):1304-1317
This study investigated the effect of camel milk protein hydrolysates (CMPH) at 100, 500 and 1,000 mg/kg of body weight (BW) for 8 wk on hyperglycemia, hyperlipidemia, and associated oxidative stress in streptozotocin-induced diabetic rats. Body weights and fasting blood glucose levels were observed after every week until 8 wk, and oral glucose tolerance test (OGTT) levels and biochemical parameters were evaluated after 8 wk in blood and serum samples. Antioxidant enzyme activity and lipid peroxidation in the liver were estimated, and histological examination of the liver and pancreatic tissues was also conducted. Results showed that CMPH at 500 mg/kg of BW [camel milk protein hydrolysate, mid-level dosage (CMPH-M)] exhibited potent hypoglycemic activity, as shown in the reduction in fasting blood glucose and OGTT levels. The hypolipidemic effect of CMPH was indicated by normalization of serum lipid levels. Significant improvement in activity of superoxide dismutase and catalase, and reduced glutathione levels were observed, along with the attenuation of malondialdehyde content in groups fed CMPH, especially CMPH-M, was observed. Decreased levels of liver function enzymes (aspartate aminotransferase and alanine aminotransferase) in the CMPH-M group was also noted. Histology of liver and pancreatic tissue displayed absence of lipid accumulation in hepatocytes and preservation of β-cells in the CMPH-M group compared with the diabetic control group. This is the first study to report anti-hyperglycemic and anti-hyperlipidemic effect of CMPH in an animal model system. This study indicates that CMPH can be suggested for its therapeutic benefits for hyperglycemia and hyperlipidemia, thus validating its use for better management of diabetes and associated comorbidities. 相似文献
46.
Deepak Kumar Nidhi Gupta Rina Ghosh Raghuvir H. Gaonkar Bikas C. Pal 《Journal of Functional Foods》2013,5(1):211-218
Carex baccans is used extensively as food additive for its medicinal and nutritional properties. Its extract demonstrated significant inhibition of α-glucosidase and α-amylase with IC50 43.32 ± 1.22 and 562.18 ± 5.98 μg/mL, respectively. A bio-assay guided approach was employed to identify the active constituent(s). Fractionation and purification of the extract led to the isolation of a potent inhibitor, (+)-α-viniferin, and of weak inhibitors smiglasides A and B. (+)-α-Viniferin was quantified in the extract and fractions using HPLC and the method was validated for linearity, limit of detection, limit of quantification, precision, and accuracy. The calibration curve showed good linearity (r2 > 0.999) in the range of 7.813–250 μg/mL. The identification of α-glucosidase and α-amylase inhibitory activity in C. baccans supports the possible use of the plant as functional food for the management of diabetes. The validated HPLC method for the study of plant extracts will be useful in future research. 相似文献
47.
Multi-users (MUs) along the communication links cause noise and traffic in the channel. The prediction of availability and the optimal usage of channels are the main objectives of the multi-input multi-output (MIMO) system. Several optimisation algorithms select the optimal channel for the users effectively. But the high-error rate and the probability values are the two major problems in traditionally optimised channel selection methods. The bandwidth allotted for information transmission is minimum. Moreover, the outage probability values are maximum in traditional scheduling algorithms. This paper proposes the new optimisation algorithm that predicts the channels for transmission and adaptive spectrum matching concept to predict the suitable channel from allocated bands. Also, the prioritisation on high-spectrum intensity basis assures an efficient data delivery to the receiver. The scheduling of available channels and data prioritisation minimises the error probability rates. This paper investigates the effectiveness of proposed optimal channel utilisation against the different modulation schemes such as three-dimensional complementary codes, linear network coding with the quadrature phase shift keying in terms of the average block error probability and bit error rate. 相似文献
48.
Bhupendra Chudasama Anjana K. Vala Nidhi Andhariya R. V. Upadhyay R. V. Mehta 《Nano Research》2009,2(12):955-965
We describe a simple one-pot thermal decomposition method for the production of a stable colloidal suspension of narrowly
dispersed superparamagnetic Fe3O4-Ag core-shell nanostructures. These biocompatible nanostructures are highly toxic to microorganisms. Antimicrobial activity
studies were carried out on both Gram negative (Escherichia coli and Proteus vulgaris) and Gram positive (Bacillus megaterium and Staphylococcus aureus) bacterial strains. Efforts have been made to understand the underlying molecular mechanism of such antibacterial actions.
The effect of the core-shell nanostructures on Gram negative strains was found to be better than that observed for silver
nanoparticles. The minimum inhibitory concentration (MIC) values of these nanostructures were found to be considerably lower
than those of commercially available antibiotics. We attribute this enhanced antibacterial effect of the nanostructures to
their stability as a colloid in the medium, which modulates the phosphotyrosine profile of the bacterial proteins and arrests
bacterial growth. We also demonstrate that these core-shell nanostructures can be removed from the medium by means of an external
magnetic field which provides a mechanism to prevent uncontrolled waste disposal of these potentially hazardous nanostructures.
相似文献
49.
Many cancers lack the expression of methylthioadenosine phosphorylase (MTAP). These cancers require adenylosuccinate synthetase (AdSS) for nucleic acid synthesis. By inhibiting adenylosuccinate synthetase, we potentially have a new therapeutic agent. Bisubstrate inhibitors were synthesized and evaluated against purified AdSS. The best activity was obtained with adenosine bearing a four-carbon linker that connects the N-formyl-N-hydroxy moiety to the 6-position of the purine nucleoside. 相似文献
50.
Traditional definitions of capacity of CDMA networks are either related to the number of calls they can handle (pole capacity)
or to the arrival rate that guarantees that the rejection rate (or outage) is below a given fraction (Erlang capacity). We
extend the latter definition to other quality of service (QoS). We consider best-effort (BE) traffic sharing the network resources
with real-time (RT) applications. As is often the case in CDMA systems, we assume that the BE traffic access is done using
a time-shared channel (such as the HDR or the HSDPA). BE applications can adapt their instantaneous transmission rate to the
available one and thus need not be subject to admission control or outages. Their meaningful QoS is the average delay (i.e.
the sojourn time). The delay aware capacity is then defined as the arrival rate of BE calls that the system can handle such
that their expected delay is bounded by a given constant. We compute in this paper both the blocking probability of the RT
traffic having an adaptive Grade of Service (GoS) as well as the expected delay of the BE traffic for an uplink multicell
WCDMA system. This yields the Erlang capacity for former and the delay capacity for the latter.
A shorter version of this work was presented at the IEEE WCNC 2003 in New Orleans, LA, USA.
Nidhi Hegde received the B.Sc. degree with specialization in Biochemistry (1995) from the University of Alberta, Canada, and the M.Sc
(1997) in Computer Science and the Ph.D (2000) degree in Telecommunications and Computer Networking, both at the University
of Missouri-Kansas City, USA. She has been with France Telecom R&D since January 2005. Her research interests include performance
evaluation of networks, with an emphasis on wireless networks.
E. Altman received the B.Sc. degree in electrical engineering (1984), the B.A. degree in physics (1984) and the Ph.D. degree in electrical
engineering (1990), all from the Technion-Israel Institute, Haifa. In (1990) he further received his B.Mus. degree in music
composition in Tel-Aviv university. Since 1990, he has been with INRIA (National research institute in informatics and control)
in Sophia-Antipolis, France. His current research interests include performance evaluation and control of telecommunication
networks and in particular congestion control, wireless communications and networking games. He is in the editorial board
of several scientific journals: Stochastic Models, JEDC, COMNET, SIAM SICON and WINET. He has been the (co)chairman of the
program committee of several international conferences and workshops (on game theory, networking games and mobile networks).
More informaion can be found at 相似文献