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Maja D. Markovic Vesna V. Panic Sanja I. Seslija Ana D. Milivojevic Pavle M. Spasojevic Nevenka M. Boskovic-Vragolovic Rada V. Pjanovic 《Polymer Engineering and Science》2020,60(8):2008-2022
Carriers for targeted delivery and controlled release of poorly water-soluble active substances (PWSAS) are facing three challenges: (a) the encapsulation issues, (b) limitations of PWSAS water solubility, and (c) burst drug release which can be pharmacologically dangerous and economically inefficient. The present study brings a novel strategy for encapsulation and controlled release of PWSAS—caffeine in concentrations which are higher than its maximal water solubility without the possibility of burst effect. The modification of hydrophilic carrier based on poly(methacylic acid) was done using casein and liposomes. To further increase the maximal caffeine loading inside the carrier nicotinamide was used. The release study of the encapsulated PWSAS was elaborated with respect to morphology of the carriers and interactions that could be established between its structural components. The carriers swelling and the release of caffeine and nicotinamide were also investigated depending on caffeine concentration, the presence of different liposomal formulations and the volume ratio of liposomal formulation, in three media with different pH simulating the path of the carrier through the human gastrointestinal tract. The synthesized carriers are promising candidates for encapsulation of PWSAS in concentrations which are higher than its maximal water solubility and for the targeted delivery of those dosages. 相似文献
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Vera P. Pavlović Jelena D. Vujančević Pavle Mašković Jovana Ćirković Jelena M. Papan Darko Kosanović Miroslav D. Dramićanin Predrag B. Petrović Branislav Vlahović Vladimir B. Pavlović 《Journal of the American Ceramic Society》2019,102(12):7735-7745
Titanium dioxide is a photocatalyst, known not only for its ability to oxidize organic contaminants, but also for its antimicrobial properties. In this article, significant enhancement of the antimicrobial activity of TiO2 (up to 32 times) was demonstrated after its activation by ball milling. The antimicrobial activity was analyzed for one fungal and 13 bacterial ATCC strains using the microdilution method and recording the minimum inhibitory concentration (MIC) values. In order to further investigate the correlation between the mechanical activation of TiO2 and its antimicrobial activity, the structure, morphology and phase composition of the material were studied by means of Electron Microscopy, X-ray diffraction and nitrogen adsorption-desorption measurements. UV-Vis diffuse reflectance spectra were recorded and the Kubelka-Munk function was applied to convert reflectance into the equivalent band gap energy (Eg) and, consequently, to investigate changes in the Eg value. X-ray photoelectron spectroscopy was used to analyze the influence of mechanical activation on the Ti 2p and O 1s spectra. The presented results are expected to enable the development of more sustainable and effective advanced TiO2-based materials with antimicrobial properties that could be used in numerous green technology applications. 相似文献
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Matej Gašperin?ani Juri?i? Pavle BoškoskiJo?ef Vi?intin 《Mechanical Systems and Signal Processing》2011,25(2):537-548
In this paper we present a statistical approach to estimating the time in which an operating gear will reach a critical stage. The approach relies on measured vibration signals. From these signals features are first extracted and then their evolution over time is predicted. This is done based on a dynamic model that relates hidden degradation phenomena to measured outputs. The Expectation-Maximization algorithm is used to estimate the parameters of the underlying state-space model on line. The time to reach the safety alarm threshold is determined by estimating the distribution of the remaining useful life using the estimated linear model. The results obtained on a pilot test bed are presented. 相似文献
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Radmila V. Hercigonja Danijela D. Maksin Aleksandra B. Nastasović Snežana S. Trifunović Pavle B. Glodić Antonije E. Onjia 《应用聚合物科学杂志》2012,123(2):1273-1282
The possibility of sorption of technetium‐99 in the form of pertechnetate anion (TcO4?) and the sorption kinetics for removing TcO4? from aqueous solution by chelating polymers based on glycidyl methacrylate (GMA) were investigated. Two samples of macroporous crosslinked poly(glycidyl methacrylate‐co‐ethylene glycol dimethacrylate) (PGME), with different amount of the crosslinker (ethylene glycol dimethacrylate, EGDMA), were synthesized by suspension copolymerization and functionalized with diethylene triamine (deta). We propose that nonspecific sorption of pertechnetate anion via electrostatic interactions takes place at the protonated amino groups of macroporous crosslinked copolymer. The results of batch experiments performed at pH 1–14 showed fast sorption kinetics for removing TcO4? by amino‐functionalized PGME‐deta in a wide range of pH, that is, from 1.0 to 9.0. Almost complete removal of TcO4? (91–98%) was reached within 180 min in the stated pH range (1.0–9.0), with the sorption half‐times of under 25 min. The partitioning coefficients of linear adsorption isotherms, with 180‐min equilibrium time, reach the high values of 2130 mL g?1 and 1698 mL g?1 for the two samples of synthesized PGME‐deta. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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Pavle Boškoski Janko Petrovčič Bojan Musizza Dani Juričić 《Expert systems with applications》2011,38(11):13816-13826
Automatic end-quality assessment is a mean that helps reaching zero-fault products at the end of the manufacturing process. In this paper we present a system for assessing the quality of electronically commutated motors. The system consists of two major parts: feature extraction and overall quality assessment. The feature extraction part consists of signal processing algorithms tailored for mechanical fault detection. The quality assessment part, aimed for fault isolation and final quality decision, employs evidential reasoning for multi-attribute decision analysis. A prototype version of the system is validated on a test batch of 130 electronically commutated motors, demonstrating high diagnostic resolution and accuracy. 相似文献
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Federated trouble ticket system for service management support in loosely coupled multi‐domain environments 下载免费PDF全文
Pavle V. Vuletić Jovana J. Vuleta‐Radoičić Dimitrios Kalogeras 《International Journal of Network Management》2015,25(2):95-112
Operating services in multi‐domain environments is inherently more complex than in a single domain because of the existence of multiple managed domains with various operating procedures, devices and systems in use. This increased complexity on one side and the demand to provide efficient and reliable services in such environment on the other impose the need to automate service operations processes and procedures. However, in loosely coupled federated service environments where participating domains retain absolute control over internal resources and processes, remotely operated configuration commands, which are prerequisite for automated operations, directly threaten the autonomy of the participating members. In this article, we identify key business processes and required operating support systems components unique to federated environments by analysing process flows for services jointly provided by European National Research and Education Networks. Although we conclude that the involvement of human operators in key service operations processes is inevitable, we propose a new workflow scheme and other necessary components needed to integrate domains in a way that minimizes manual intervention. The proposed scheme interconnects independently operating trouble ticket systems (TTSs) from participating domains in a federated TTS (FTTS). The proposed FTTS is not constrained just to the basic function of TTS—fault management, but it supports all key federated service operation activities like service provisioning, problem or performance management. The proposed fully decentralized federated scheme retains the main inherent capabilities of TTSs such as tracking, escalation and expiration and at the same time supports the desired federated service communication processes. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Rates of turnover and oxidation of plasma free fatty acid (FFA) were determined in unanesthetized dogs during exercise, acute
cold exposure and anaphylactic shock, with the aid of a technique involving the continuous infusion of albumin-bound palmitate-1-14C and the simultaneous measurement of O2 uptake, CO2 output and the specific activities of CO2 and FFA. During exercise in normal untrained dogs, plasma FFA supplied 20–30% of the energy, whereas in trained dogs 70–90%
of the energy was derived from the FFA oxidation. In resting dogs at room temperature the plasma FFA level was 0.58 μEq/ml
with a turnover rate of 18.6 μEq/kg/min of which 22% was immeditely oxidized and contributed 29% to the exhaled CO2. These results were compared with data obtained in pancreatectomized and thyroidectomized dogs. Acute cold exposure (temperature
4–5C) increased the FFA level and turnover rate to 1.02 μEq/ml and 28.0 μEq/kg/min, respectively, of which 33% was immedaitely
oxidized, contributing 46% to the exhaled CO2. During anaphylactic shock, blood lactate increased, FFA level and turnover rate were reduced, and the fraction which was
immediately oxidized was depressed markedly, i.e., 3–9% of FFA turnover. Sodium lactate infusion, which induces a blood lactate
level comparable to that seen in anaphylaxis or nicotinic acid infusion, markedly decreased the level and turnover rate of
FFA. However the fraction of turnover oxidized remained the same as during the preinfusion period (range of 21–40%. Exercise
or the administration of norepinephrine during anaphylactic shock provided results suggesting that endogenous lactic acid
interferes with FFA oxidation, whereas exogenous, lactate had no effect on this oxidation. 相似文献