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101.
The use of free and immobilized Lactobacillus casei ATCC 393 on whey protein as starter culture in probiotic Feta-type cheese production was evaluated. The probiotic cultures resulted in significantly higher acidity; lower pH; reduced counts of coliforms, enterobacteria, and staphylococci; and improved quality characteristics compared with cheese with no culture. Microbiological and strain-specific multiplex PCR analysis showed that both free and immobilized L. casei ATCC 393 were detected in the novel products at levels required for conferring a probiotic effect at the end of the ripening. The effect of starter culture on production of volatile compounds was investigated by the solid-phase microextraction gas chromatography-mass spectrometry analysis technique. The immobilized cells resulted in an improved profile of aroma-related compounds and the overall high quality of the novel products was ascertained by the preliminary sensory test. Finally, the high added value produced by exploitation of whey, which is an extremely polluting industrial waste, was highlighted and assessed.  相似文献   
102.
A 1 V, programmable, accurate, high speed, single-ended charge pump is proposed, suitable for low voltage PLLs. It is designed in TSMC 90-nm digital CMOS process and it consists of four switches in a current steering configuration, a unity gain rail to rail buffer for the charge sharing effect elimination, one more rail to rail amplifier for minimizing the DC current mismatch, a programmable current bias circuitry and two drivers based on the standard cell XOR gates specific configuration for achieving good synchronization between all charge pump input pulses at the PLL lock state. Replica biasing technique is applied to all charge pump switches. Current glitches and charge mismatch are suppressed by employing a mechanism with additional switches at the output. It exhibits a maximum DC current mismatch of 1% and charge mismatch of 6% over a wide output voltage range of 0.7 V for the entire range of output currents. The wide range of the output voltage remains relatively constant and independent of the selected charge pump current amplitude. This is attained by applying appropriate variation of the W/L ratios of the bias cascode current sources via the employment of additional programmable switches such that their saturation voltages remain relatively constant, something which in turn enables the output currents range to be as wide as it is required.  相似文献   
103.
Four types of Greek olive oil were analysed for α-and γ-tocopherols by high performance liquid chromatography. Certain seed oils widely consumed in Greece were also analysed for comparison with the olive oils. Virgin, pure, residual and refined oils contained an average of 113,81,156 and 37 mg kg?1 of α-tocopherol, respectively. The α-tocopherol level within each type of olive oil appeared to be influenced by different factors. The content of y-tocopherol averaged 17 and 33 mg kg?1of virgin and residual oil, respectively. Refined and pure olive oil contained very low levels of y-tocopherol. The α-tocopherol equivalent per gram of polyunsaturated fatty acids was calculated to be 1·48, 0·60, 0·88, 1·07 and 0·58 for edible olive oils, corn, cottonseed, sunflower and partially hydrogenated soya bean oil, respectively.  相似文献   
104.
Pancreatic Cancer (PC) is recognized as a highly thrombogenic tumor; thus, low-molecular-weight heparin (LMWH) such as tinzaparin is routinely used for PC patients. On the basis of combinatorial therapy approaches to treat highly malignant and refractory cancers such as PC, we hypothesized that tinzaparin can augment the effectiveness of traditional chemotherapeutic drugs and induce efficient antitumor activity. PANC-1 and MIAPaCa-2 were incubated alone or in combination with tinzaparin, nab-paclitaxel and gemcitabine. In vivo evaluation of these compounds was performed in a NOD/SCID mouse using a model injected with PANC-1. Tinzaparin enhances the anti-tumor effects of nab-paclitaxel and gemcitabine in mtKRAS PC cell lines via apoptosis in in vitro experiments. The triple combination power acts through the induction of apoptosis, reduction of the proliferative potential and angiogenesis; hence, contributing to a decrease in tumor volume observed in vivo. The triple regimen provided an extra 24.3% tumor reduction compared to the double combination (gemcitabine plus nab-paclitaxel). Combinatorial strategies can create novel therapeutic approaches for the treatment of patients with PC, achieving a better clinical outcome and prolonged survival. Further prospective randomized research is needed and the investigation of various concentrations of tinzaparin above 150 UI/Kg, would potentially provide a valuable synergistic effect to the conventional therapeutic compounds.  相似文献   
105.
This paper presents a methodology for the aggregation of nodal generation loss factors into zonal loss factors, taking into account the geographic as well as the “electrical” proximity of the nodes to the zone centers. The annual net economic consequence (gain or loss) of each generator from the aggregation is estimated and used as an index for the evaluation of the methodology. Additionally, an algorithm for the automated zonal configuration with pre-defined economic consequences is presented. Starting from one zone comprising the whole power system, the algorithm finds the number of zones that keep the economic consequences of zonalization below a pre-defined threshold, and the resulting zonal configuration. By performing an exhaustive search using this algorithm for the “best” initial root node, an optimal zonal configuration can be identified that achieves the pre-defined level of economic consequences with the minimum number of zones. Numerical results from a real power system, the Greek power system, are presented and discussed.  相似文献   
106.
107.
The vehicle delay tolerant networks (DTNs) make opportunistic communications by utilizing the mobility of vehicles, where the node makes delay-tolerant based “carry and forward” mechanism to deliver the packets. The routing schemes for vehicle networks are challenging for varied network environment. Most of the existing DTN routing including routing for vehicular DTNs mainly focus on metrics such as delay, hop count and bandwidth, etc. A new focus in green communications is with the goal of saving energy by optimizing network performance and ultimately protecting the natural climate. The energy–efficient communication schemes designed for vehicular networks are imminent because of the pollution, energy consumption and heat dissipation. In this paper, we present a directional routing and scheduling scheme (DRSS) for green vehicle DTNs by using Nash Q-learning approach that can optimize the energy efficiency with the considerations of congestion, buffer and delay. Our scheme solves the routing and scheduling problem as a learning process by geographic routing and flow control toward the optimal direction. To speed up the learning process, our scheme uses a hybrid method with forwarding and replication according to traffic pattern. The DRSS algorithm explores the possible strategies, and then exploits the knowledge obtained to adapt its strategy and achieve the desired overall objective when considering the stochastic non-cooperative game in on-line multi-commodity routing situations. The simulation results of a vehicular DTN with predetermined mobility model show DRSS achieves good energy efficiency with learning ability, which can guarantee the delivery ratio within the delay bound.  相似文献   
108.
Frequencies above 10 GHz nowadays may be employed either for backhaul networks of mobile communication access networks or for broadband fixed wireless access networks. Millimeter wave networks can afford large bandwidth by carrying the aggregate traffic through different network nodes. Consequently, many line-of-sight multi-hop transmissions may occur. At these frequency bands, rain attenuation is the dominant fading mechanism that aggravates the outage performance of these networks. The objective of this paper is the presentation of analytical models for the calculation of the end-to-end performance analysis of a triple-hop system with non-regenerative and regenerative relays using the trivariate lognormal distribution along with a physical model for the calculation of the correlation coefficients among the rain fading channels. Moreover, an accurate rain attenuation time series synthesizer based on multi-dimensional first order Stochastic Differential eqnarrays is employed in order to validate the analytical results. Finally, extended numerical results investigate the impact of various operational and geographical parameters, as well as the influence of the arbitrary position of the relays on the outage system performance.  相似文献   
109.
Quality of Service (QoS) characterization and prediction is of utmost importance in contemporary operating cellular communications networks. Measurements data of speech and video telephony have been collected using modern experimental equipment. More specifically, key performance indicators of radio, speech and video quality are evoked. The objective of our study is to critically investigate the performance of speech and video telephony at live cellular networks correlating significant QoS parameters from radio and the service side. Simple non-linear regression models are also proposed for speech and video quality prediction. Finally, the paper represents the splendid positive influences of the continuous performance evaluation for the optimization of the mobile networks. There are also briefly given guidelines for mobile networks benchmarking.  相似文献   
110.
In the present contribution, five unloaded AT-cut quartz crystal microbalance (QCM) sensors with nominal resonant frequencies equal to 5, 5.2 and 10 MHz, bearing silver (5.2 MHz) and gold electrodes (5 and 10 MHz) on their main surfaces, were bonded on a high pressure cell and studied with respect to their electrical and frequency response in the temperature range from 20 °C to 150 °C at a nitrogen atmosphere (P?=?1 atm). The goal was the qualitative and the quantitative identification of energy dissipation mechanisms of quartz resonators, based on their electrical response and effective properties (quartz viscosity and oscillation area). Electrical response measurements took place with high frequency impedance analysis (HF-IA), while admittance data were processed with the use of equivalent circuit theory and the Differential Evolution heuristic for nonlinear optimization, equipped with an error analysis module. Apart from the inherent energy dissipation due to sensor mounting and electrode related mass and stress effect, dissipation was also induced due to the manifestation of thermally active point defects at temperatures between 65 °C and 145 °C. These point defects are attributed to the movement of interstitial sodium ions within the crystal lattice. Energy dissipation was also observed due to temperature dependent (70–90 °C) creep deformation of the 60Sn-40Pb solder joints which bonded the mounted sensors to the experimental setup. A critical discussion on the magnitude of all observed dissipation mechanisms is presented.  相似文献   
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