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The purpose of our research was to prepare nanoencapsulated PET textile materials, which would be used as odor carriers (underwear and bed sheets with aromatherapy activities) or would act as malodorous absorbers (absorption of cigarette smell). We grafted β‐cyclodextrin onto PET textile materials by using a polyfunctional reagent 1,2,3,4‐butanetetracarboxylic acid. To reduce the curing temperature of the reaction, catalysts such as sodium hypophosphite and cyanamide were used. We prepared nanoencapsulated polyester textile materials with increased adsorption capacity and with delayed release of volatile or active compounds. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
24.
Various machine learning techniques have been applied to different problems in survival analysis in the last decade. They were usually adapted to learning from censored survival data by using the information on observation time. This includes learning from parts of the data or interventions to the learning algorithms. Efficient models were established in various fields of clinical medicine and bioinformatics. In this paper, we propose a pre-processing method for adapting the censored survival data to be used with ordinary machine learning algorithms. This is done by pre-assigning censored instances a positive or negative outcome according to their features and observation time. The proposed procedure calculates the goodness of fit of each censored instance to both the distribution of positives and the spoiled distribution of negatives in the entire dataset and relabels that instance accordingly. We performed a thorough empirical testing of our method in a simulation study and on two real-world medical datasets, using the naive Bayes classifier and decision trees. When compared to one of the popular ML methods dealing with survival, our method provided good results, especially when applied to heavily censored data. 相似文献
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Oskar Bera Jelena Pavličević Bojana Ikonić Jelena Lubura Dragan Govedarica Predrag Kojić 《Polymer Engineering and Science》2021,61(3):879-890
Although extensive research has been carried out on the understanding of the complex vulcanization process, the influence of reversion through exposure time and temperature on the vulcanization degree remains unclear. Therefore, the main aim of this study was a novel optimization approach that can help the industrial practitioners to select the optimal operating parameters, exposure time, and molding temperature, to achieve desired vulcanization degree of selected product. Spheres of four different diameters (2.5, 5, 10, and 20 cm) were selected as test geometry for simulation and optimization of rubber molding. Obtained vulcanization rheometer data for commercially available rubber blend (NR/SBR) were fitted by a new modeling approach, dividing vulcanization curve into two fitting sets: curing and reversion. The heat transfer equations for chosen geometry were coupled with proposed kinetic model. A new temperature-dependent kinetic parameter x, as the maximal reversion degree, was introduced, enabling determination of the lowest operating molding temperature (Tmin = 132.36 °C), preventing high reversion and overheating of the rubber product. The final optimization goal was assessment of the optimal temperature and vulcanization time dependence on the rubber products dimensions. Proposed models have precise prediction with R2 values greater than 0.8328 and MAPE less than 2.3099%. 相似文献
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Milena Todorovic Balint Jelena Jelicic Biljana Mihaljevic Jelena Kostic Bojana Stanic Bela Balint Nadja Pejanovic Bojana Lucic Natasa Tosic Irena Marjanovic Maja Stojiljkovic Teodora Karan-Djurasevic Ognjen Perisic Goran Rakocevic Milos Popovic Sava Raicevic Jelena Bila Darko Antic Bosko Andjelic Sonja Pavlovic 《International journal of molecular sciences》2016,17(5)
The existence of a potential primary central nervous system lymphoma-specific genomic signature that differs from the systemic form of diffuse large B cell lymphoma (DLBCL) has been suggested, but is still controversial. We investigated 19 patients with primary DLBCL of central nervous system (DLBCL CNS) using the TruSeq Amplicon Cancer Panel (TSACP) for 48 cancer-related genes. Next generation sequencing (NGS) analyses have revealed that over 80% of potentially protein-changing mutations were located in eight genes (CTNNB1, PIK3CA, PTEN, ATM, KRAS, PTPN11, TP53 and JAK3), pointing to the potential role of these genes in lymphomagenesis. TP53 was the only gene harboring mutations in all 19 patients. In addition, the presence of mutated TP53 and ATM genes correlated with a higher total number of mutations in other analyzed genes. Furthermore, the presence of mutated ATM correlated with poorer event-free survival (EFS) (p = 0.036). The presence of the mutated SMO gene correlated with earlier disease relapse (p = 0.023), inferior event-free survival (p = 0.011) and overall survival (OS) (p = 0.017), while mutations in the PTEN gene were associated with inferior OS (p = 0.048). Our findings suggest that the TP53 and ATM genes could be involved in the molecular pathophysiology of primary DLBCL CNS, whereas mutations in the PTEN and SMO genes could affect survival regardless of the initial treatment approach. 相似文献
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1. Sympathetic nerve stimulation causes contraction of the dilator muscle and the large arterioles of the iris via the activation of alpha 1B-adrenoceptors. We have investigated whether increases in adenosine 3': 5'-cyclic monophosphate (cyclic AMP) and the activation of receptors in these tissues can modulate these nerve-mediated contractions. 2. Increasing intracellular cyclic AMP with dibutyryl cyclic AMP (1 mM), forskolin (50 microM) or isobutylmethylxanthine (100 microM) produced relaxation of both the dilator and the arterioles, abolished the nerve-mediated constriction of the arterioles, but potentiated the nerve-mediated contraction of the iris dilator. 3. Pretreatment of the preparations with cholera toxin, to activate Gs permanently, caused a dilatation of the arterioles and abolished the nerve-mediated constriction but had no effect on the dilator muscle. 4. The beta-adrenoceptor agonist, isoprenaline (1 microM), the adenosine-A1,-A2 agonist, N-ethylcarboxamidoadenosine NECA (100 nM), in the presence of the A1-selective antagonist, 8-cyclopentyl-1, 3-dipropylxanthine (DPCPX, 10 nM), and calcitonin gene-related peptide (CGRP, 10 nM) all separately caused a dilatation of the arterioles and abolished the nerve-mediated constriction, while only isoprenaline (1 microM) produced an effect on the dilator, i.e. a relaxation but a potentiation of the nerve-mediated contraction. These results suggest the presence of at least 3 types of receptor linked to Gs and an increase in cyclic AMP in the arterioles, i.e. beta-adrenoceptor, adenosine-A2 and CGRP, but only 1 Gs-linked receptor, i.e. beta-adrenoceptors, on the dilator muscle cells.2+ ' 相似文献
28.
Drew Michael R.; Zupan Bojana; Cooke Anna; Couvillon P. A.; Balsam Peter D. 《Canadian Metallurgical Quarterly》2005,31(1):31
The peak procedure was used to characterize response timing during acquisition and maintenance of conditioned responding in goldfish. Subjects received light-shock pairings with a 5- or 15-s interstimulus interval. On interspersed peak trials, the conditioned stimulus light was presented for 45 s and no shock was delivered. Peaks in the conditioned response, general activity, occurred at about the time of the expected unconditioned stimulus, and variability in the activity distribution was scalar. Modeling of the changes in the activity distributions over sessions revealed that the temporal features of the conditioned response changed very little during acquisition. The data suggest that times are learned early in training, and, contrary to I. P. Pavlov's (1927/1960) concept of "inhibition of delay," that timing is learning when to respond rather than learning when not to respond. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
29.
Sandra Kurko?eljka Raškovi? Nikola Novakovi?Bojana Paskaš Mamula Zoran Jovanovi?Zvezdana Baš?arevi? Jasmina Grbovi? Novakovi? Ljiljana Matovi? 《International Journal of Hydrogen Energy》2011,36(1):549-554
To understand the influence of various crystallographic phases on hydrogen storage properties, ball milling of MgH2 with hexagonal (α) and cubic (β) SiC have been performed. Structural characterization of all samples has been done by X-ray diffraction (XRD) analysis, particle size analysis and scanning electron microscopy (SEM). Investigation of hydrogen desorption properties of prepared nanocomposites has been done using temperature programmed desorption (TPD) technique. Despite the results of structural and morphological characterization of obtained nanocomposites are very similar, TPD spectra show significant differences regarding existence of intermediate temperature peak. In the sample milled with hexagonal SiC this peak originates both from H2 and H2O, while in the sample milled with cubic phase it only comes from H2O. Both samples exhibit low temperature H2 peak at 385 K. 相似文献
30.
Bojana Z. Nikolic Mihajlo C. Stefanovic Stefan R. Panic Jelena A. Anastasov Borivoje Milosevic 《ETRI Journal》2011,33(3):320-325
This paper considers the effects of simultaneous correlated multipath fading and shadowing on the performances of a signal‐to‐interference ratio (SIR)‐based dual‐branch selection combining (SC) diversity receiver. This analysis includes the presence of cochannel interference. A generalized fading/shadowing channel model in an interference‐limited correlated fading environment is modeled by generalized‐K distribution. Closed‐form expressions are obtained for probability density function and cumulative distribution function of the SC output SIR, as well as for the outage probability. Based on this, the influence of various fading and shadowing parameter values and the correlation level on the outage probability is examined. 相似文献