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11.
This paper presents a new approach to prediction of resource demand for future handoff calls in multimedia wireless IP networks. Our approach is based on application of multi‐input‐multi‐output (MIMO) multiplicative autoregressive‐integrated‐moving average (ARIMA) (p,d,q)x(P,D,Q)S models fitted to the traffic data measured in the considered cell itself and on the new call admission control (CAC) algorithm that simultaneously maximizes the system throughput while keeping the handoff call dropping probability (CDP) below the targeted value. The main advantages of the proposed approach are the following: first, the proposed multi‐variable prediction method gives on average better predictions (i.e. narrower prediction confidence interval) for realistic traffic situations, which results in lower new call blocking probability (CBP) at the targeted handoff CDP and second, the model is simple to implement since it does not require communication among the adjacent cells. Simulation results show the superiority of the proposed MIMO prediction approach combined with the proposed call admission control algorithm for some typical nonstationary situations in comparison with univariate models. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
12.
Milos Bandjur Nikola Sekulovic Mihajlo Stefanovic Aleksandra Golubovic Petar Spalevic Dejan Milic 《ETRI Journal》2013,35(4):722-725
In this letter, a wireless communication system with microdiversity and macrodiversity reception in gamma‐shadowed Rician fading channels is considered. Exact and rapidly converging infinite‐series expressions for the average level crossing rate and average fade duration at the output of the system are provided. Numerical results are presented graphically to illustrate the proposed mathematical analysis and to examine the effects of the system's parameters on the quantities considered. 相似文献
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Emil Malchev Nikola Spassov Ghenov Nikolina Ivanova Ioncheva Stoyan Stoychev Tanchev Krassimira Kirilova Kalpakchieva 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,189(3):229-231
Summary The higher fatty acids of dried red pepper of the variety of Gorogled were identified by gas chromatography with using help of authentic compounds. Their amounts were determined using on absolute calibration method.The following acids were established: lauric, myrastic, palmitic, palmitoleic, stearic, oleic, linoleic, linolenic,arachidic and behenic acids. The results obtained from the quantitative measurements showed that linoleic, linolenic and palmitic acids amounted to 80% of the total acids.The quantitative changes of identified acids in red pepper, of dried at 60°, 70°, 80° and 90 °C red pepper and stored as dried red pepper and red pepper powder over a 6-months period investigated.The results show that under the drying temperatures applied the amount of all fatty acids decreased with an increase in the temperature. During a storage a period of 3 months the amount of the respective acids decreased while the process was the most expressed in red pepper dried at a temperature of t = 70 °C.After a 6-months storage period under the drying condition applied the dried red pepper contained a greater amount of fatty acids compared with stored for 3 months.
Identifikation und Veränderungen der höheren Fettsäuren von gemahlenem Paprika und von getrockneten ungemahlenen Paprikaschoten
Zusammenfassung Es wurden gaschromatographisch mit Hilfe von Vergleichsubstanzen die höheren Fettsäuren, die im gemahlenen Paprika (Sorte Gorogled) enthalten sind, identifiziert. Die Mengen wurden nach der Methode der absoluten Kalibrierung bestimmt. Es wurden folgende Säuren festgestellt: Laurinsäure, Myristin-, Palmitin-, Palmitoolein-, Stearin-, Olein-, Linol-, Linolen-, Arachin- und Behensäure. Die quantitativen Ergebnisse zeigen, daß die Menge der Linolen-, Linol- und Palmitinsäure 80% der Gesamtsäurenmenge darstellt. Es wurden die quantitativen Veränderungen der Fettsäuren von Paprika (Sorte Gorogled) bei Temperaturen von 60 °, 70 °, 80 ° und 90 °C, getrocknet und als getrockneter ungemahlener bzw.gemahlener Paprika, gelagert und innerhalb von 6 Monaten in Abständen von 3 Monaten verfolgt. Bei den angewendeten Trocknungstemperaturen nimmt die Menge der einzelnen Fettsäuren in dem getrockneten ungemahlenen Paprika mit Erhöhung der Trocknungstemperatur ab. Die Lagerung des getrockneten ungemahlenen Paprikas innerhalb von 3 Monaten führt zur Abnahme der einzelnen Fettsäuren, wobei dieser Prozeß am stärksten bei einer Trocknungstemperatur von 70 °C verläuft. Nach einer 6monatigen Lagerung des getrockneten und ungemahlenen Paprikas, nach Trocknung und bei den o. g. vier Temperaturen, ist die Menge der Fettsäuren höher im Vergleich zu jener der Fettsäuren in getrocknetem ungemahlenem Paprika nach 3 Monaten. Nach 3 Monaten enthält der gemahlene Paprika weniger Fettsäuren als der getrocknete und ungemahlene Paprika.相似文献
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Pawe Mieszczaski Szmon Januszyk Nikola Zmarzy Piotr Ossowski Konrad Dziobek Dorota Sagan Dariusz Boro Marcin Opawski Beniamin Oskar Grabarek 《International journal of molecular sciences》2022,23(24)
Reactive oxygen species are formed as by-products of normal cell metabolism. They are needed to maintain cell homeostasis and signaling, which is possible due to defense systems. Disruption of this balance leads to oxidative stress that can induce cancer. Redox regulation by miRNAs may be a potential therapeutic target. The aim of the study was to assess the activity of genes associated with oxidative stress in endometrial cancer and to determine their relationship with miRNAs. The study included 45 patients with endometrioid endometrial cancer and 45 without neoplastic changes. The expression profile of genes associated with oxidative stress was determined with mRNA microarrays, RT-qPCR and ELISA. The miRNA prediction was performed based on the miRNA microarray experiment and the mirDB tool. PRDX2 and AQP1 showed overexpression that was probably not related to miRNA activity. A high level of PKD2 may be the result of a decrease in the activity of miR-195-3p, miR-20a, miR-134. A SOD3 level reduction can be caused by miR-328, miR-363. In addition, miR-363 can also regulate KLF2 expression. In the course of endometrial cancer, the phenomenon of oxidative stress is observed, the regulation of which may be influenced by miRNAs. 相似文献
18.
Liadys Mora Lagares Yunierkis Prez-Castillo Nikola Minovski Marjana Novi
《International journal of molecular sciences》2022,23(1)
P-Glycoprotein (P-gp) is a transmembrane protein belonging to the ATP binding cassette superfamily of transporters, and it is a xenobiotic efflux pump that limits intracellular drug accumulation by pumping compounds out of cells. P-gp contributes to a reduction in toxicity, and has broad substrate specificity. It is involved in the failure of many cancer and antiviral chemotherapies due to the phenomenon of multidrug resistance (MDR), in which the membrane transporter removes chemotherapeutic drugs from target cells. Understanding the details of the ligand–P-gp interaction is therefore critical for the development of drugs that can overcome the MDR phenomenon, for the early identification of P-gp substrates that will help us to obtain a more effective prediction of toxicity, and for the subsequent outdesign of substrate properties if needed. In this work, a series of molecular dynamics (MD) simulations of human P-gp (hP-gp) in an explicit membrane-and-water environment were performed to investigate the effects of binding different compounds on the conformational dynamics of P-gp. The results revealed significant differences in the behaviour of P-gp in the presence of active and non-active compounds within the binding pocket, as different patterns of movement were identified that could be correlated with conformational changes leading to the activation of the translocation mechanism. The predicted ligand–P-gp interactions are in good agreement with the available experimental data, as well as the estimation of the binding-free energies of the studied complexes, demonstrating the validity of the results derived from the MD simulations. 相似文献
19.
Jean-Claude Imber Andrea Roccuzzo Alexandra Sthli Nikola Saulacic James Deschner Anton Sculean Dieter Daniel Bosshardt 《International journal of molecular sciences》2021,22(20)
(1) Aim: To immunohistochemically evaluate the effect of a volume-stable collagen scaffold (VCMX) on periodontal regeneration. (2) Methods: In eight beagle dogs, acute two-wall intrabony defects were treated with open flap debridement either with VCMX (test) or without (control). After 12 weeks, eight defects out of four animals were processed for paraffin histology and immunohistochemistry. (3) Results: All defects (four test + four control) revealed periodontal regeneration with cementum and bone formation. VCMX remnants were integrated in bone, periodontal ligament (PDL), and cementum. No differences in immunohistochemical labeling patterns were observed between test and control sites. New bone and cementum were labeled for bone sialoprotein, while the regenerated PDL was labeled for periostin and collagen type 1. Cytokeratin-positive epithelial cell rests of Malassez were detected in 50% of the defects. The regenerated PDL demonstrated a larger blood vessel area at the test (14.48% ± 3.52%) than at control sites (8.04% ± 1.85%, p = 0.0007). The number of blood vessels was higher in the regenerated PDL (test + control) compared to the pristine one (p = 0.012). The cell proliferative index was not statistically significantly different in pristine and regenerated PDL. (4) Conclusions: The data suggest a positive effect of VCMX on angiogenesis and an equally high cell turnover in the regenerated and pristine PDL. This VCMX supported periodontal regeneration in intrabony defects. 相似文献
20.
Removal of oxygen from feedwater is of paramount importance for safe boiler operation. Insufficient extraction of oxygen in deaeration vessels will lead to limited efficiency of oxygen scavengers and unsafe plant operation. The presented sizing procedure for packed deaeration columns is based on the similarity theory between heat and mass transfer and existing procedures. The goal of the proposed technique is not to achieve optimization of column dimensions, but to ensure that there is no undersizing of the packing height. This approach is justified considering the relatively low capital costs of deaeration columns in boiler plants. The proposed equations are based on an experimental setup involving several hundred operating regimes which have been verified and confirmed to have a high degree of accuracy. 相似文献