36 research outputs found

    Hands help hearing: Facilitatory audiotactile interaction at low sound-intensity levels

    Get PDF
    Auditory and vibrotactile stimuli share similar temporal patterns. A psychophysical experiment was performed to test whether this similarity would lead into an intermodal bias in perception of sound intensity. Nine normal-hearing subjects performed a loudness-matching task of faint tones, adjusting the probe tone to sound equally loud as a reference tone. The task was performed both when the subjects were touching and when they were not touching a tube that vibrated simultaneously with the probe tone. The subjects chose on average 12% lower intensities (p<0.01) for the probe tone when they touched the tube, suggesting facilitatory interaction between auditory and tactile senses in normal-hearing subjects.Peer reviewe

    Asthmatics Exhibit Altered Oxylipin Profiles Compared to Healthy Individuals after Subway Air Exposure

    Get PDF
    Asthma is a chronic inflammatory lung disease that causes significant morbidity and mortality worldwide. Air pollutants such as particulate matter (PM) and oxidants are important factors in causing exacerbations in asthmatics, and the source and composition of pollutants greatly affects pathological implications.This randomized crossover study investigated responses of the respiratory system to Stockholm subway air in asthmatics and healthy individuals. Eicosanoids and other oxylipins were quantified in the distal lung to provide a measure of shifts in lipid mediators in association with exposure to subway air relative to ambient air.Sixty-four oxylipins representing the cyclooxygenase (COX), lipoxygenase (LOX) and cytochrome P450 (CYP) metabolic pathways were screened using liquid chromatography-tandem mass spectrometry (LC-MS/MS) of bronchoalveolar lavage (BAL)-fluid. Validations through immunocytochemistry staining of BAL-cells were performed for 15-LOX-1, COX-1, COX-2 and peroxisome proliferator-activated receptor gamma (PPARγ). Multivariate statistics were employed to interrogate acquired oxylipin and immunocytochemistry data in combination with patient clinical information.Asthmatics and healthy individuals exhibited divergent oxylipin profiles following exposure to ambient and subway air. Significant changes were observed in 8 metabolites of linoleic- and α-linolenic acid synthesized via the 15-LOX pathway, and of the COX product prostaglandin E(2) (PGE(2)). Oxylipin levels were increased in healthy individuals following exposure to subway air, whereas asthmatics evidenced decreases or no change.Several of the altered oxylipins have known or suspected bronchoprotective or anti-inflammatory effects, suggesting a possible reduced anti-inflammatory response in asthmatics following exposure to subway air. These observations may have ramifications for sensitive subpopulations in urban areas

    Audiotactile interactions in temporal perception

    Full text link

    Assessing the Carbon Footprint of Biochar from Willow Grown on Marginal Lands in Finland

    No full text
    Willow biochar can help to sequestrate carbon. However, biomasses should not be grown on arable lands, as it would increase competition with food production and lead to sustainability issues such as increased food prices and decreased food security. The purpose of this study is to calculate the carbon footprint (CF) of willow biochar in Finland and assess the greenhouse gas compensation potential of marginal lands if they are utilized for willow biochar production. The CF of willow biochar is inadequately assessed together with marginal lands in the literature. A cradle-to-grave Life Cycle Assessment (LCA) of willow biochar was conducted. The results were then applied to assess the total CF of marginal lands. It was found that the CF of willow biochar is −1875 kgCO2eq t−1 of dry biochar. Grown on marginal lands in Finland, willow biochar could compensate 7.7% of yearly agricultural greenhouse gas emissions. On buffer zones, willow biochar could also compensate some of the emissions depending on the zone size. The results of the study support current findings of biochar as a carbon negative product. The study also indicates that willow biochar produced in marginal lands can be used to compensate agricultural greenhouse gas emissions to some extent

    Effect of temperature and concentration of precursors on morphology and photocatalytic activity of zinc oxide thin films prepared by hydrothermal route

    Get PDF
    Zinc oxide (ZnO) is an important semiconductive material due to its potential applications, such as conductive gas sensors, transparent conductive electrodes, solar cells, and photocatalysts. Photocatalytic activity can be exploited in the decomposition of hazardous pollutants from environment. In this study, we produced zinc oxide thin films on stainless steel plates by hydrothermal method varying the precursor concentration (from 0.029 M to 0.16 M) and the synthesis temperature (from 70 °C to 90 °C). Morphology of the synthesized films was examined using field-emission scanning electron microscopy (FESEM) and photocatalytic activity of the films was characterized using methylene blue decomposition tests. It was found that the morphology of the nanostructures was strongly affected by the precursor concentration and the temperature of the synthesis. At lower concentrations zinc oxide grew as thin needlelike nanorods of uniform length and shape and aligned perpendicular to the stainless steel substrate surface. At higher concentrations the shape of the rods transformed towards hexagon shaped units and further on towards flaky platelets. Temperature changes caused variations in the coating thickness and the orientation of the crystal units. It was also observed, that the photocatalytic activity of the prepared films was clearly dependent on the morphology of the surfaces.publishedVersionPeer reviewe

    Gas phase synthesis of encapsulated iron oxide–titanium dioxide composite nanoparticles by spray pyrolysis

    No full text
    Composite nanoparticles are of a great interest due to the possibility of combining properties of several different materials. In this study, a spray pyrolysis process utilizing flame-synthesized nanopowder was used to generate iron oxide–titanium dioxide (γ-Fe2O3–TiO2) composite nanoparticles. Iron oxide and titanium dioxide were selected because they are known to have magnetic and photocatalytic properties, respectively. First, dry γ-Fe2O3 nanopowder was prepared with the liquid flame spray technique. After that, the flame-synthesized nanoparticles were mixed with liquid titanium(IV) isopropoxide (TTIP) and isopropyl alcohol. This mixed-phase precursor was sprayed into a tube furnace where TTIP thermally decomposed to form solid TiO2, encapsulating the γ-Fe2O3 powder particles. The synthesized nanoparticles were characterized with aerosol measurements, transmission electron microscopy, X-ray diffraction and Raman spectroscopy. The size distributions of the composite nanoparticles were broad, and the mode diameters were 80–130 nm. The particles consisted of a γ-Fe2O3 agglomerate that was either partially or fully encapsulated by a spherical TiO2 particle, depending on the concentration of TTIP in the mixed-phase precursor. The flame-synthesized iron oxide powder was crystalline maghemite, whereas, spray pyrolyzed titanium dioxide had amorphous phase. The as-synthesized composite nanoparticles were calcinated to attain crystalline anatase TiO2. The crystal structures as well as demonstrated photoactivity and magnetic response suggest that the composite nanoparticles could find use as magnetically separable photocatalyst

    Recycling mine tailings in chemically bonded ceramics:a review

    No full text
    Abstract Mine tailings account for most of the environmental incidents related to the extractive industry, with risks increasing due to steadily rising tonnage of low-grade ore and extreme weather events. Recycling of tailings in raw-material-intensive applications presents an interesting alternative to costly tailings management with associated restoration efforts. Chemically bonded ceramics may offer a route to upgrading mine tailings into raw materials for ceramics. In this review such chemically bonded ceramic methods that may be used to recycle mine tailings as raw materials, are reviewed while focusing in particular on two methods: 1) geopolymerization/alkali activation and 2) chemically bonded phosphate ceramics. The aim of the review is not to give exhaustive review on the wide topic, but to scope the required boundary conditions that need to be met for such utilization. According to the findings, alkali activation has been studied for 28 separate silicate minerals in the scientific literature, and presents a viable method, which is already in commercial use in calcium-rich cement-like binder applications. Phosphate bonding literature is more focused on phosphate containing minerals and waste encapsulation. Very little work has been done on low-calcium tailings utilization with either technology, and more knowledge is needed on the effect of different pre-treatment methods to increase reactivity of mine tailings in chemically bonded ceramics
    corecore