Music recommendation hybrid system for improving recognition ability using collaborative filtering and impression words

Music therapy for improving recognition ability may be more effective when the favorite music of each person is adopted. In the proposed system, first, the recommendation process using collaborative filtering is terminated when no users in the reference list have the same preference of recommended music as that of a new user. Then, the second recommendation process finds the most similar music, from the scores for impression words, to those successfully recommended among music not recommended up to the moment. The average number of recommended songs for each user by the proposed system was 12.1, whereas that of collaborative filtering was 4.3. The recommendation accuracy of the proposed system was 70.2 %, whereas that of collaborative filtering was 62.1 %. The ratings of songs can be added on a user-by-user basis in the recommendation process, and this increased number of cases improves the recommendation accuracy and increases the number of recommended songs.     

Anomalous diffusion modeling by fractal and fractional derivatives

This paper makes an attempt to develop a fractal derivative model of anomalous diffusion. We also derive the fundamental solution of the fractal derivative equation for anomalous diffusion, which characterizes a clear power law. This new model is compared with the corresponding fractional derivative model in terms of computational efficiency, diffusion velocity, and heavy tail property. The merits and distinctions of these two models of anomalous diffusion are then summarized.     

Kinetics of supercritical carbon dioxide extraction of borage and evening primrose seed oil

In the present work, high‐pressure extraction of borage (Borago officinalis L.) and evening primrose (Oenothera biennis L.) seed oil, containing the valuable γ‐linolenic acid (GLA), has been investigated. Extraction was performed with supercritical carbon dioxide on a semi‐continuous flow apparatus at pressures of 200 and 300 bar, and at temperatures of 40 and 60 °C. A constant flow rate of carbon dioxide in the range from 0.17 to 0.20 kg/h was maintained during extraction. The extraction yields obtained using dense CO₂ were similar to those obtained with conventional extraction using hexane as solvent. The composition of extracted crude oil was determined by GC analysis. The best results were obtained at 300 bar and 40 °C for both seed types extracted, where the quality of oil was highest with regard to GLA content. The evening primrose seed oil extracted with supercritical fluid extraction was particularly rich in unsaturated fatty acids: up to 89.7 wt‐% of total free fatty acids in the oil. The dynamic behavior of the extraction runs was analyzed using two mathematical models for describing the constant rate period and the subsequent falling rate period. Based on the experimental data, external mass transfer coefficients, diffusion coefficients and diffusivity in solid phase were estimated. Results showed good agreement between calculated and experimental data.     

The impact of K+ content on the structural transformations and morphological changes during the thermal treatment of α-MnO2 nanorods

The effect of heat treatment on the structure and morphology of α-MnO₂ nanorods with different potassium contents was investigated. These nanorods, prepared by ion exchange, were thermally treated at 500, 800, 1000 and 1100 °C, and characterized with X-ray diffraction and electron microscopy. The structure and morphology of the starting sample remained preserved up to 500 °C. The first structural and morphological changes were observed when α-MnO₂ nanorods with different potassium contents were heated at 800 °C. The sample with the highest potassium content decomposed only partially to α-Mn₂O₃, while the decomposition of the α-MnO₂ to α-Mn₂O₃ was complete in the sample with the lowest potassium content. Morphologically, both samples were composed of nanorods and grains. When the temperature was increased to 1000 and 1100 °C, both the structure and morphology changed: the α-MnO₂ nanorods completely decomposed to Mn₃O₄ grains. The acidic media in which the ion exchange took place shortened the α-MnO₂ nanorods.     

Determination of the geographical origin of Slovenian black locust,lime and chestnut honey

The geographical origin of three Slovenian unifloral honey types (black locust, lime and chestnut) was investigated by analysis of some physico-chemical parameters, the elemental content using total reflection X-ray fluorescence spectrometry (TXRF) and the stable carbon and nitrogen isotope ratios using isotope ratio mass spectrometry (IRMS). The results were interpreted by chemometric methods. A total of 122 samples of Slovenian black locust, lime and chestnut honeys were collected from domestic beekeepers all over Slovenia for three years. Slovenia is a small country by area, but paedologically and climatically diverse, therefore offering interesting possibilities for studying geographical influences. The combination of the investigated parameters offers the possibility of distinguishing among samples of specific honey types from the four different Slovenian natural-geographical macroregions, namely the Alpine, Dinaric, Pannonnian and Mediterranean regions. Lime honey samples were 100% correctly classified, while the success rates for black locust and chestnut honeys were slightly lower at 98.2% and 94.6%, respectively.     

In vitro antioxidant and antiproliferative activity of three rosemary (Rosmarinus officinalis L.) extract formulations

Antioxidant and antiproliferative activities of three rosemary extract formulations (VivOX 20, VivOX 40 and Inolens 50) with different contents of carnosic acid, carnosol and methylcarnosol were tested in vitro. Electron spin resonance measurements revealed that Inolens 50 extract that contained highest amount of carnosic acid was the most potent scavenger of hydroxyl (concentration of extract where 50% of its maximal scavenging activity is observed, that is, EC₅₀, 109.54 μg mL^?1), superoxide anion (EC₅₀ = 7.94 μg mL^?1) and 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) (EC₅₀ = 27.4 μg mL^?1)‐free radicals. Comparison of the radar charts of standard antioxidants and rosemary extracts showed similarity between antioxidant characteristics of Inolens 50 and chlorogenic and caffeic acids. Tested rosemary extracts exhibited significant (P ≤ 0.01) antiproliferative effect in cervix epitheloid carcinoma (HeLa), breast adenocarcinoma (MCF7) and colon adenocarcinoma (HT‐29) cell lines. In both MCF7 and HeLa cell lines, the extracts yielded very low IC₅₀ values (concentration of extract needed to inhibit cell growth by 50%), the most pronounced being for Inolens 50 in MCF7 (IC₅₀ = 9.95 μg mL^?1) and VivOX 20 in HeLa cell line (IC₅₀ = 10.02 μg mL^?1). The obtained results may provide support for the use of tested rosemary extracts as nutraceuticals and phytopharmaceuticals.     

LC-DAD-ESI/MS analysis of flavonoids and abscisic acid with chemometric approach for the classification of Slovenian honey

The flavonoid profiles of seven types of Slovenian honey were analysed. The flavonoids are phenolic compounds that have health-related properties, and their presence in honey is attributed to the plants visited by the bees. The flavonoids were extracted from honey samples by solid-phase extraction and analysed by liquid chromatography, with diode array detection and electrospray ionisation mass spectrometry (LC-DAD-ESI/MS). The honey samples had similar, but quantitatively different, flavonoid profiles. The flavonoids myricetin, luteolin, quercetin, naringenin, apigenin, kaempferol, pinocembrin, chrysin and galangin were identified using reference standards, while pinobanksin was tentatively identified through its retention time, m/z, UV spectrum and MS/MS data. Two non-phenolic compounds were also identified; cis–trans-abscisic acid and, tentatively, trans–trans-abscisic acid. The analysis did not show any specific compounds to use as markers for determination of the botanical origins of these different types of Slovenian honey. Further analyses of more honey samples with additional standards are needed to identify such potential markers, although linear discriminant analysis correctly classified 85% of these honey samples according to their botanical origins.     

Phase equilibria of vanillins in compressed gases

Solid–liquid phase transitions of vanillin, ethylvanillin, o-vanillin and o-ethylvanillin in compressed hydrocarbons (isobutane and propane), fluorinated hydrocarbons (R23, R134a and R236fa) and sulphur hexafluoride (SF₆) were determined with a modified capillary method in a pressure range between 0.1 and 31.0 MPa. Equilibrium solubilities of vanillins in compressed fluorinated hydrocarbons were determined at temperatures 313.2 and 333.2 K and over a pressure range between 1.1 and 26.0 MPa with a static–analytic method. Experimental solubility data were correlated by a density-based Chrastil model.Results showed that phase equilibria of vanillins in investigated compressed gases are influenced by the type of alchoxy group (methoxy or ethoxy) and the position of OH group (ortho or para), bound to the aromatic ring of solute, as well as the molecular structure of the gas. Three phase SLG curves in p,T-projections mainly exhibited temperature minimums and negative slopes dp/dT, with a maximum melting point depression between 9 and 21 K; all systems with SF₆ exhibited a continuous positive slope dp/dT of approximately 4.5 MPa/K. SLG curves with a temperature maximum at low pressure were observed for systems of o-vanillins with R23. Solubilities of o-vanillins in R23 and R236fa were higher in comparison with p-vanillins, whereas, in the case of R134a, the solubilities were influenced by the alchoxy group bound on aromatic ring: vanillin and o-vanillin with methoxy group are more soluble than vanillins with ethoxy group (ethylvanillin and o-ethylvanillin). The highest solubility of all four vanillins was observed in R236fa.