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Opis: How does linguistic structure affect children’s acquisition of early number word meanings? Previous studies have tested this question by comparing how children learning languages with different grammatical representations of number learn the meanings of labels for small numbers, like 1, 2, and 3. For example, children who acquire a language with singular-plural marking, like English, are faster to learn the word for 1 than children learning a language that lacks the singular-plural distinction, perhaps because the word for 1 is always used in singular contexts, highlighting its meaning. These studies are problematic, however, because reported differences in number word learning may be due to unmeasured cross-cultural differences rather than specific linguistic differences. To address this problem, we investigated number word learning in four groups of children from a single culture who spoke different dialects of the same language that differed chiefly with respect to how they grammatically mark number. We found that learning a dialect which features “dual” morphology (marking of pairs) accelerated children’s acquisition of the number word two relative to learning a “non-dual” dialect of the same language.
Ključne besede: števila, številke, slovnično število, dvojina, narečja, usvajanje, učenje, slovenščina, angleščina, numbers, grammatical number, dual, dialects, acquisition, learning, Slovenian, English
Objavljeno v RUNG: 10.08.2016; Ogledov: 5008; Prenosov: 242
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Opis: Supported Fe2O3/WO3 nanocomposites were fabricated by an original vapor phase approach, involving the chemical vapor deposition (CVD) of Fe2O3 on Ti sheets and the subsequent radio frequency (RF)-sputtering of WO3. Particular attention was dedicated to the control of the W/Fe ratio, in order to tailor the composition of the resulting materials. The target systems were analyzed by the joint use of complementary techniques, that is, X-ray diffraction (XRD), field emission-scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), energy dispersive X-ray spectroscopy (EDXS), X-ray photoelectron spectroscopy (XPS), secondary ion mass spectrometry (SIMS), and optical absorption spectroscopy. The results showed the uniform decoration of α-Fe2O3 (hematite) globular particles by tiny WO3 aggregates, whose content could be controlled by modulations of the sole sputtering time. The photocatalytic degradation of phenol in the liquid phase was selected as a test reaction for a preliminary investigation of the system behavior in wastewater treatment applications. The system activity under both UVand Vis light illumination may open doors for further material optimization in view of real-world end-uses.
Ključne besede: Fe2O3, WO3, Nanocomposites, Chemical vapor deposition, Sputtering, Photocatalysis
Objavljeno v RUNG: 03.08.2016; Ogledov: 4981; Prenosov: 0
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Opis: The study is aimed at evaluating the potential of immobilized TiO2-based zeolite composite for solar-driven photocatalytic water treatment. In that purpose, TiO2-iron-exchanged zeolite (FeZ) composite was prepared using commercial Aeroxide TiO2 P25 and iron-exchanged zeolite of ZSM5 type, FeZ. The activity of TiO2-FeZ, immobilized on glass support, was evaluated under solar irradiation for removal of diclofenac (DCF) in water. TiO2-FeZ immobilized in a form of thin film was characterized for its morphology, structure, and composition using scanning electron microscopy/energydispersive x-ray spectroscopy (SEM/EDX). Diffuse reflectance spectroscopy (DRS) was used to determine potential changes in band gaps of prepared TiO2-FeZ in comparison to pure TiO2. The influence of pH, concentration of hydrogen peroxide, FeZ wt% within the composite, and photocatalyst dosage on DCF removal and conversion efficiency by solar/ TiO2-FeZ/H2O2 process was investigated. TiO2-FeZ demonstrated higher photocatalytic activity than pure TiO2 under solar irradiation in acidic conditions and presence of H2O2.
Ključne besede: Photocatalysis, Thin films, TiO2-FeZ, Solar irradiation, Diclofenac, Water Treatment
Objavljeno v RUNG: 22.07.2016; Ogledov: 6160; Prenosov: 0
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Opis: Obesity and MetS (Metabolic Syndrome) are both linked to persistent long-term hormonal and metabolic changes. In most of the studies, cortisol (C) and dehydroepiandrosterone (DHEA) concentrations have been measured in obese and normal-weight subjects, obtaining heterogeneous results. Plasma, saliva and urine, matrices that represent timepoint or short-term steroids exposure, were used for these studies. The aim was to study C, DHEA and C/DHEA ratio of mice pups in the hair, matrix capable of providing cumulative hormonal exposure. Sixty C57Bl/6 mice pups (30 males and 30 females) were housed in a temperature-controlled environment (22±2°C) and on a 12h light/dark schedule, under ad-libitum access to food and water for 16 weeks (welfare: Italian Law Decree 116-92 and EC Directive 86-609-EEC). Control and experimental diets were offered immediately after weaning (3 weeks old pups), for 16 weeks. Four experimental checkpoints were established (T1: 4 weeks, T2: 8 weeks, T3: 12 weeks and T4: 16 weeks of diet). T3 and T4 showed the hormonal concentrations of pubertal animals. Twentyseven pups (13 females and 14 males) were randomly group-housed in cages (6 for T1, 5 for T2, 6 for T3, 10 for T4) and assigned to control diet (CTRL: D12328, Research Diets, New Brunswick, NJ). 33 pups (17 females and 16 males) were randomly group-housed in cages (5 for T1, 6 for T2 and T3, 16 for T4) and assigned to the HFHC diet (HFHC: D12331, Research Diets, New Brunswick, NJ - plus 42g/L fructose/sucrose in drinking water). At each experimental checkpoint, all the animals of one cage for each experimental group were suppressed. Hair strands were carefully cut with scissors as close as possible to the skin from the back of the mice, paying attention to not to wound the animals. Hair was stored in an envelope at RT in a dry room until use. C and DHEA hair concentrations was measured by a solid-phase microtiter RIA assay (Peric et al., 2016 adapted in the mouse). Only at 8 weeks the HFHC group showed significantly higher C concentrations than the CTRL group (1.56±0.06 vs 1.92±0.130 pg/mg; P<0.05). DHEA concentrations were significantly reduced in the HFHC group than the CTRL group at 4 (114.64±13.93 vs 69.08±5.33 pg/mg; P<0.05), 8 (71.67±7.08 vs 50.38±4.74 pg/mg; P<0.05), 12 (73.27±8.29 vs 41.59±1.60 pg/mg; P<0.01) and 16 weeks (65.26±3.35 vs 55.05±1.84 pg/mg; P<0.05). The C/DHEA ratio was significantly increased in the HFHC than the CTRL group, at 8 (0.023±0.002 vs 0.040±0.005; P<0.01), 12 (0.024±0.003 vs 0.036±0.004; P<0.05) and 16 weeks (0.019±0.001 vs 0.025±0.002; P<0.01). The gender effect was not significant. Taking into account the lag time required for the hair emersion from the skin (about 1 week), the significant stimulation of the C at 8 weeks in the HFHC group refers to its chronic elevation from 5 to 7 weeks of treatment when the animals were not pubertal. Conversely, DHEA shows a chronic reduction in obese mice leading to consider an independent adrenal regulation of C and DHEA, both stimulated by ACTH. Research was supported by the Project CBM (MIUR DM60643). Peric et al. 2016 J Appl Anim Welf Sci 18:1-8.
Ključne besede: DIET, HAIR, CORTISOL, DHEA, MOUSE
Objavljeno v RUNG: 21.07.2016; Ogledov: 4989; Prenosov: 0
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Opis: Photocatalytic ozonation process using TiO2 photocatalyst (O3/TiO2/UV – PH-OZ) conducted in acidic water environment often leads to synergistic effect in terms of decomposition and mineralization of aqueous organic contaminants, which makes the process suitable for waste water treatment or pretreatment of drinking water. [1,2] The synergism is among other factors (pH, O3 dose, T,…) greatly influenced by photocatalyst physicochemical properties and pollutant type. In the first part of the study, five different commercial TiO2 photocatalysts (P25, PC500, PC100, PC10 and JRC-TiO-6) were used in O2/TiO2/UV, O3/TiO2 and O3/TiO2/UV advanced oxidation systems for degradation of two pollutants (dichloroacetic acid - DCAA and thiacloprid – neonicotinoid pesticide), simultaneously present in water solution. [3] Results of PH-OZ (O3/TiO2/UV) experiments showed that in contrast to DCAA which adsorbs on TiO2 surface, synergistic effect is much more expressed in the case of thiacloprid which doesn’t adsorb. The influence of BET surface area of the photocatalyst and its dispersivity will be discussed. In the second part of this study, selected catalysts were immobilized on a proper support to avoid post-filtration step in the process of greywater treatment. A good adhesion of a catalyst on various supports was successfully achieved by immobilization of commercial TiO2 powders (P25, P90, PC500) with the help of a sol-gel silica-titania binder [4]. For the purpose of simulated greywater treatment, special compact reactor was designed and developed, utilizing Al2O3 porous reticulated monolith foams as TiO2 carriers and UVA-lamps inside (Fig. 1). [5] With degradation of LAS+PBIS and Reactive blue 19 (RB 19) as representatives of surfactants and textile dyes respectively, commonly found in household greywater, and phenol as trace contaminant, an evaluation of PH-OZ and photocatalytic oxidation has been performed (an example in Fig. 2). Synergistic effect of PH-OZ was generally much more expressed in mineralization reactions, showing TOC half lives of less than one hour for the mixture of pollutants in compact reactor. [5] Due to its superior cleaning capacity, PH-OZ process employing efficient photocatalysts is suitable for treating wastewaters also with higher loading of organic pollutants. 1. U. Černigoj, U.Lavrenčič Štangar, J. Jirkovsky, J. Hazard. Mater. (2010) 177:399–406. 2. U. Černigoj, U.Lavrenčič Štangar, P. Trebše, Appl. Catal. B Environ. (2007) 75:229–238. 3. M. Kete, U. Černigoj, U. Lavrenčič Štangar: Photocatalytic ozonation – study of reaction parameters and mechanism, article under submission 4. M. Kete, E. Pavlica, F. Fresno, G. Bratina, U. Lavrenčič Štangar, Environ. Sci. Pollut. Res. (2014) 21:11238–11249. 5. M. Kete: Towards efficient removal of contaminants in water from household appliances by TiO2-photocatalysis: design, optimization and performance studies of the photoreactor with immobilized catalysts, Doctoral dissertation (2015), University of Nova Gorica, Nova Gorica.
Ključne besede: photocatalysis, ozonation, TiO2, dichloroacetic acid, thiacloprid, mechanisms, LAS+PBIS, Reactive blue 19, phenol
Objavljeno v RUNG: 21.07.2016; Ogledov: 6868; Prenosov: 0
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