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51.
The effect of relative humidity (RH) and light conditions on the oxidative stability of sunflower oil (SO) stabilised with oleoresin rosemary + ascorbyl palmitate (SOR), sage + ascorbyl palmitate (SOS) and tertiary butyl hydroquinone (SOT) was investigated. The SO without additive (SOC) served as positive control. Oil samples were subjected to 3 RH (29%, 52% and 75%) and two light conditions (dark, D and fluorescent light (600 lx), L) at 60 °C for 7 days. The oxidative stability was monitored by peroxide value (PV), conjugated diene value (CDV), free fatty acids (FFAs) and Rancimat induction period (IP). A direct relationship was noted between RH and increase in PV, CDV and FFA levels irrespective of light conditions. The detrimental effect of light on the oxidative stability was prominently noted at higher RH (75%) which followed an order: SOC > SOT > SOR > SOS. The samples stored under lower RH (29% and 52%), and dark conditions were better stabilised than light‐exposed counterparts.  相似文献   
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Food Science and Biotechnology - The process of cellular senescence is rapidly emerging as a modulator of organismal aging and disease. Targeting the development and removal of senescent cells is...  相似文献   
53.
The sunflower oil–oleoresin rosemary (Rosmarinus officinalis L.) blends (SORB) at 9 different concentrations (200 to 2000 mg/kg), sunflower oil–tertiary butyl hydroquinone (SOTBHQ) at 200 mg/kg and control (without preservatives) (SOcontrol) were oxidized using Rancimat (temperature: 100 to 130 °C; airflow rate: 20 L/h). The oxidative stability of blends was expressed using induction period (IP), oil stability index and photochemiluminescence assay. The linear regression models were generated by plotting ln IP with temperature to estimate the shelf life at 20 °C (SL20; R2 > 0.90). Principal component analysis (PCA) and hierarchical cluster analysis (HCA) was used to classify the oil blends depending upon the oxidative stability and kinetic parameters. The Arrhenius equation adequately described the temperature‐dependent kinetics (R2 > 0.90, P < 0.05) and kinetic parameters viz. activation energies, activation enthalpies, and entropies were calculated in the range of 92.07 to 100.50 kJ/mol, 88.85 to 97.28 kJ/mol, ?33.33 to ?1.13 J/mol K, respectively. Using PCA, a satisfactory discrimination was noted among SORB, SOTBHQ, and SOcontrol samples. HCA classified the oil blends into 3 different clusters (I, II, and III) where SORB1200 and SORB1500 were grouped together in close proximity with SOTBHQ indicating the comparable oxidative stability. The SL20 was estimated to be 3790, 6974, and 4179 h for SOcontrol, SOTBHQ, and SORB1500, respectively. The multivariate kinetic approach effectively screened SORB1500 as the best blend conferring the highest oxidative stability to sunflower oil. This approach can be adopted for quick and reliable estimation of the oxidative stability of oil samples.  相似文献   
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This paper presents the theoretical investigation of CDM opportunity in a township at Jaipur, India. The purpose of study is to identify and analyze the various opportunities viz., installation of solar water heater, energy efficient lighting, energy efficient air conditioners, and energy efficient submersible water pumps in desert coolers and thus achieve a considerable (65.7?%) reduction in GHG emissions. Out of the various opportunities considered, the retrofitting with solar water heater can be recommended for CDM. Though, the retrofitting with energy efficient lighting, energy efficient air conditioners and energy efficient submersible water pumps in desert coolers claimed CO2 emission reduction of 104.84, 25.92, and 36.94?tons per annum, respectively, but the only opportunity which got through CDM was retrofitting with solar water heater claiming 115.70?tCO2 (100?%) emission reductions per annum which could result into net earnings of 115.70 CERs. The simple and discounted payback period for all four project activities are also calculated with and without CDM and tax benefits.  相似文献   
56.
Wireless Networks - With the advancement of communication and sensor technologies, it has become possible to develop low-cost circuitry to sense and transmit the state of surroundings. Wireless...  相似文献   
57.
Sixteen healthy young adults (ages 18-32) and 16 healthy older adults (ages 67-81) completed a delayed response task in which they saw the following visual sequence: memory stimuli (2 abstract shapes; 3,000 ms), a blank delay (5,000 ms), a probe stimulus of variable duration (one abstract shape; 125, 250, 500, 1,000, or 2,000 ms), and a mask (500 ms). Subjects decided whether the probe stimulus matched either of the memory stimuli; they were instructed to respond during the mask, placing greater emphasis on speed than accuracy. The authors used D. L. Hintzman & T. Curran's (1994) 3-parameter compound bounded exponential model of speed-accuracy tradeoff to describe changes in discriminability associated with total processing time. Group-level analysis revealed a higher rate parameter and a higher asymptote parameter for the young adult group, but no difference across groups in x-intercept. Proxy measures of cognitive reserve (Y. Stern et al., 2005) predicted the rate parameter value, particularly in older adults. Results suggest that in working memory, aging impairs both the maximum capacity for discriminability and the rate of information accumulation, but not the temporal threshold for discriminability. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Recent explosive growth in physical memory configurations inverts the problem faced by traditional operating systems, which were built around the assumption of limited physical memory and plentiful virtual memory. With the introduction of the Pentium Pro, there is an aberration in the historical trend towards increased virtual space. Such processors have 36‐bit physical and 32‐bit logical addressing; with traditional algorithms, the smaller virtual space limits the number of concurrent processes as well as the total physical memory usable by an application. To address these problems, two general principles can be applied to any operating system to reduce its virtual memory needs: first, multiplexing different physical addresses over the same virtual—as opposed to multiplexing different virtual over the same physical, where the optimization was to share the physical memory across multiple processes; second, optimize virtual consumption by kernel pagepool data, by organizing data structures to extend their physical memory reach using the same amount of virtual space. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   
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Of all the methods customarily used to transform E. coli we found only electroporation to be effective for transformation of the Gram-negative bacterium Vitreoscilla, yielding 5.10(5) transformants/microgram of plasmid DNA. The conditions used were close to those described for E. coli E. coli plasmids are stably maintained in Vitreoscilla. This is the first report of exogenous DNA transfer in Vitreoscilla which opens the way for the application of recombinant-DNA techniques to study this unique group of organisms.  相似文献   
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