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391.
Fernando A. P. Bar��qui Antonio Petraglia 《Circuits, Systems, and Signal Processing》2011,30(2):355-370
This paper presents a new CMOS analog fully differential voltage buffer, with large dynamic range and low harmonic distortion.
Its design is based on the use of cross-coupled input differential pairs and internal current feedback. Two design approaches
are proposed, with the objective of minimizing power consumption: one for switched-capacitor circuits and the other for Gm-C
circuits. Design equations and simulation results are presented as well. Illustrative design examples are developed for a
0.35-μm CMOS technology using a power supply voltage of 2.5 V. 相似文献
392.
Diego P. Pinto-Roa Benjamín Barán Carlos A. Brizuela 《Photonic Network Communications》2011,22(1):23-45
The performance of wavelength division multiplexing (WDM) networks is highly dependent on the wavelength converter allocation
and routing problems. Typically, these problems have been treated as independent problems under dynamic traffic; however,
in order to achieved good system’s performance, both problems should be dealt with together. To this aim, this work proposes
a joint optimization approach where allocations for converters and paths for routing are calculated simultaneously. A multi-objective
evolutionary algorithm is proposed to minimize the number of wavelength converters and the overall blocking probability at
the same time. Extensive simulations show promising results in the sense that our approach not only generates better trade-off
solutions in comparison with an iterative-joint state-of-the-art approach but also constitutes an effective tool to better
understand different trade-offs in the design of WDM networks. 相似文献
393.
In the paper we present a logic-based system that makes possible the comparison of the requirements of particular sectors (e.g. agriculture, industry, construction, mining, energy) and social requirements (e.g. living conditions, employment, education, culture) at the level of the territorial system. It is based on a hierarchical model of national, county and district level activities. Every level has its own goals and the problem is to find an acceptable solution for these goals. Its implementation depends upon a special extension of the logic-based programming language PROLOG, known as TSPROLOG. The basic function of a territorial system can be viewed as the reproduction of social resources on an increasing scale. The task (the basic activity) of the system is the production of the territorial conditions of living and of the way of life. During this process of production, the system takes up raw material, energy and information from its environment. The processes that take place in the system are determined by natural/human resources, social activities, markets of technical elements and technically utilized areas. The external and internal relations of the system are regulated by the market of transport activities. 相似文献
394.
Sánchez Jaeger A Vargas SI Solano Rodríguez L Díaz N Adela Barón M 《Archivos latinoamericanos de nutrición》2006,56(3):224-228
The validity of the energy/protein index (EPI) in the detection of overweight was assessed in 163 low income children (four to six years old) from Valencia, Venezuela. Weight, height, arm circumference, and skinfolds were taken. Weight for height (W/H), limb fat area (LFA), and EPI were calculated. All subjects with W/H < or =p10 were considered deficient, with W/H between >p10 and < or =p90 normal, and with W/H and LFA >p90 in excess. Percentile distribution of EPI for age and gender was calculated, regarding below the norm all subjects < or =p10, normal those > p10 and p90, and above the norm those >p90. Validity was assessed through sensibility, specificity, and likelihood ratio. Student's t test and ANOVA were used for group comparisons (p < 0.05). According to the nutritional diagnosis, 27.60% of the children were deficient, 66.88% normal, and 15.52% in excess. According to the EPI, 7.36% of the sample was considered below the norm, 82.20% normal, and 10.44% above the norm. The EPI decreased with age in boys, and in the 6 years old group was significantly higher for girls. Lastly, an EPI above the norm is eleven times more likely to occur in a subject considered in excess than in subjects considered normal. For deficiency, the tests did not meet the expected values. 相似文献
395.
Nitzan R Bruckental I Bar Shira Z Maltz E Halachmi I 《Journal of dairy science》2006,89(11):4462-4472
Simulation models of parallel, rotary, and side-opening milking parlors were built that could predict milking parlor performance according to herd size, number of milking stalls, labor quality, and cow characteristics. The models were validated by statistically comparing the duration of the simulated milking process with actual data collected at 3 dairy farms during 12 mo. Various scenarios were generated to study parlor performance, and the results indicated that for a parlor with up to 14 milking stalls, a side-opening design provided greater capacity than parallel or rotary parlors. Performance of a side-opening parlor was reduced by enlargement up to 20 milking stalls. For 10 to 40 milking stalls, a rotary design gave better performance than a double parallel design in terms of milking process duration and stall utilization. The presented models can serve as a practical tool in designing new parlors or changing operations of existing ones. 相似文献
396.
Necati Barış Tuncel Ayşen Uygur Yonca Karagül Yüceer 《Journal of the American Oil Chemists' Society》2017,94(6):877-884
Flaxseeds were roasted at 1150 W/m2 radiation intensity with short and medium wave infrared (IR) emitters for specific durations, which provided good visual and sensory quality. The effects of IR roasting on color properties, hydrogen cyanide (HCN) content, tocopherols and fatty acid composition of the flaxseed and flaxseed oil were investigated. Further, flaxseeds were stored for 6 months and free fatty acid content and peroxide values were followed at 1-month intervals to understand the effect of IR treatment on hydrolytic and oxidative stability. HCN content of the flaxseeds was reduced up to 59% with IR roasting. Tocopherol content of the IR roasted flaxseed oil was higher than that of the control. No notable variation was observed in fatty acid composition with regard to IR treatment. Free fatty acid content of IR roasted flaxseeds did not increase during storage, while peroxide value of the seeds significantly increased up to 95 mEq O2/kg oil. 相似文献
397.
J. Barłowska M. Szwajkowska Z. Litwińczuk J. Król 《Comprehensive Reviews in Food Science and Food Safety》2011,10(6):291-302
Abstract: The analysis of nutritional value and selected traits of technological suitability of milk was performed on the basis of the available literature. This analysis concerned various animal species used for dairy purposes (cattle, buffalo, goats, sheep, camels, donkeys, and horses). It has been stated that a considerable diversity exists in the analyzed parameters and traits of milk, which results in various directions of milk utilization. Cow milk accounts for more than 80% of world milk production. It is the most universal raw material for processing, which is reflected in the broadest spectrum of manufactured products. Sheep and buffalo milk, regarding their high content of protein, including casein, and fat, make a very good raw material for processing, especially cheesemaking. Donkey and horse milk have the most comparable protein composition to human milk (low content of casein, lack of αs1‐casein fraction and β‐lactoglobulin, and high content of lysozyme). Donkey milk is additionally characterized by a fatty acid profile distinctive from milk of other analyzed animal species. Camel milk also has valuable nutritional properties as it contains a high proportion of antibacterial substances and 30 times higher concentration of vitamin C in comparison to cow milk. The composition of goat milk allows using it as the raw material for dairy processing and also to some extent as a therapeutical product (low content or lack of αs1‐casein). 相似文献
398.
Expansion behaviour for a bed of binary mixture of the irregularly shaped particle in Newtonian liquid was measured in two different circular columns. Variations in the physical parameters on the expansion behaviour have been reported. Bed expansion increases with an increase in liquid velocity and a decrease in particle diameter. Static bed height and expansion of the bed are low for higher diameter columns. An empirical correlation has been developed for predicting the ratio of bed height at the fluidized condition to the initial bed height as a function of the physical and dynamic variables related to the system for the binary particle mixtures. The correlation coefficient and variance of the estimate are 0.9299 and 0.0013, respectively, which is acceptable statistical accuracy. A hybrid of the genetic algorithm and neural network modelling for the prediction of the same has also been attempted where the input parameters are optimized using the Levenberg–Marquardt algorithm. With a relative error of 1.46%, the genetic algorithm performed well. So, the modelling has successfully predicted the bed height ratio at fluidized conditions to the initial bed height. 相似文献
399.
Rohit Shrivastava Nitin Tupperwar Bar Schwartz Nofar Baron Michal Shapira 《International journal of molecular sciences》2021,22(8)
Leishmania parasites cycle between sand fly vectors and mammalian hosts, transforming from extracellular promastigotes that reside in the vectors’ alimentary canal to obligatory intracellular non-motile amastigotes that are harbored by macrophages of the mammalian hosts. The transition between vector and host exposes them to a broad range of environmental conditions that induces a developmental program of gene expression, with translation regulation playing a key role. The Leishmania genome encodes six paralogs of the cap-binding protein eIF4E. All six isoforms show a relatively low degree of conservation with eIF4Es of other eukaryotes, as well as among themselves. This variability could suggest that they have been assigned discrete roles that could contribute to their survival under the changing environmental conditions. Here, we describe LeishIF4E-5, a LeishIF4E paralog. Despite the low sequence conservation observed between LeishIF4E-5 and other LeishIF4Es, the three aromatic residues in its cap-binding pocket are conserved, in accordance with its cap-binding activity. However, the cap-binding activity of LeishIF4E-5 is restricted to the promastigote life form and not observed in amastigotes. The overexpression of LeishIF4E-5 shows a decline in cell proliferation and an overall reduction in global translation. Immuno-cytochemical analysis shows that LeishIF4E-5 is localized in the cytoplasm, with a non-uniform distribution. Mass spectrometry analysis of proteins that co-purify with LeishIF4E-5 highlighted proteins involved in RNA metabolism, along with two LeishIF4G paralogs, LeishIF4G-1 and LeishIF4G-2. These vary in their conserved eIF4E binding motif, possibly suggesting that they can form different complexes. 相似文献
400.
Effect of sourdough starter and fungal proteases on gluten content and sensory properties of tarhana
Seda İçen Barçın Karakaş-Budak Muharrem Certel 《International Journal of Food Science & Technology》2021,56(5):2557-2564
In this study, gluten degradation during prolonged tarhana fermentation was monitored in a traditional dough as well as in dough containing sourdough starter, peptidase additives and combination of both. Gluten content, determined using the sandwich ELISA assay method, was reduced significantly in the first 5 days of fermentation for all formulations. After 30 days into fermentation, approximately 15% and 20% reduction of gluten was observed in the traditional dough and sourdough starter added dough, respectively. In enzyme supplemented formulations, the mean gluten levels were below 20 ppm by 20 days of fermentation. Results showed that proteolytic enzyme addition to the dough mix can potentially render long fermented tarhana a food which conforms to regulations set forth for gluten-free foods, even though wheat flour is one of the main production ingredients. Sensory evaluation of the 30 day fermented tarhana samples revealed differences in sourness and odour properties of the products. 相似文献