Authors:I. Tamáska, Z. Vértesy, A. Deák, P. Petrik, K. Kertész and László Biró
Bioinspired 1+2D nanoarchitectures inspired by the quasi-ordered structures occurring in photonic nano-architectures of biological origin, like for example butterfly scales, were produced by depositing a layer of SiO2 nanospheres (156 nm and 292 nm in diameter) on Si wafers, over which a regular multilayer composed from three alternating layers of SiO2 and TiO2 was deposited by physical vapor deposition. Flat multilayers were deposited in the same run on oxidized Si (324 nm SiO2 thickness) for comparison. Different types of disorder (in plane and out of plane) were purposefully allowed in the 1+2D nanoarchitectures. The positions of the specular reflection maxima for the flat multilayer and for the two different bioinspired nanoarchitectures were found to be similar. Additionally to this, the bioinspired nanoarchitectures exhibited angle independent diffuse reflection too, which was absent in the flat multilayer. Different model calculations were made to explain the specular and diffuse optical properties of the samples. Satisfactory agreement was obtained between experimental data and model calculations.
Authors:Z. Áy, Z. Kerényi, A. Takács, M. Papp, I. Petróczi, R. Gáborjányi, D. Silhavy, J. Pauk and Z. Kertész
The reliable monitoring of field virus infections of crop species is important for both farmers and plant breeders. The aim of this study was to detect virus infections of winter wheat in the 2006/2007 season. Twelve well-known winter wheat varieties were sown on two different dates (11
of October and 3
of November 2006). Leaves of two individuals from each genotype were collected on 23rd of April 2007 to detect the virus infections (
Barley stripe mosaic virus
Barley yellow dwarf virus
Wheat dwarf virus
— WDV and
Wheat streak mosaic virus
— WSMV) after an extra mild autumn- and wintertime. Virus infections were detected by enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). The aphid-transmitted BYDV-PAV was found frequently whereas other viruses were presented very rarely or were not detected. Forty-six per cent of the tested wheat plants proved to be infected by BYDV-PAV in ELISA, while using PCR, the virus infections with BYDV-PAV was found in 58% of the samples. Further, these results suggest that the optimal sowing time is critical in the control of cereal virus diseases, and additionally, that wheat varieties respond to the virus infections differently.
Authors:F. Samu, F. Kádár, G. Ónodi, M. Kertész, A. Szirányi, É. Szita, K. Fetykó, D. Neidert, E. Botos and V. Altbäcker
Recent environmental and land use changes have made wildfires more frequent in natural habitats of the Kiskunság Sand Ridge on the Hungarian Plain. In a study initiated 2.5 years after an extensive fire that destroyed half of the area of a sand grassland — juniper, poplar forest steppe habitat, we assessed the effects of fire on two generalist arthropod groups: spiders and carabid beetles, as well as on the vegetation. Utilizing the natural experiment situation, samples were taken by pitfalls and suction sampling during a 1.5 years period in four 1 ha blocks, two of which were on the burnt part of the habitat, and two in the unburnt control. At the time of the investigation, in the burnt area the vegetation in the grass layer showed a quick but not complete recovery, while the canopy layer of the juniper bushes burnt down with no sign of regeneration. Carabid beetles and spiders showed differences in recovery after fire. In the carabid assemblages of the burnt parts — compared to the unburnt control — there were over three times more beetles, out of which significantly more represented the macropterous life form and granivorous feeding strategy. There was a higher ratio of pioneer species and a simplified assemblage structure in the burnt area, which meant that the conservation value of the carabid assemblage became lower there. In contrast, for the spider assemblage quantitative changes in abundance and species numbers were not significant, and the differences in species composition did not lead to a decrease in conservation value. Spider species in the burnt plots could not be described as pioneer species, rather they had ecological characteristics that suited the changed vegetation structure. Comparing the two groups, to repopulate the burnt areas, dispersal abilities proved to be more limiting for carabids. However, in both groups a strong assemblage level adaptation could be observed to the postfire conditions. In spiders, species with a stratum preference for the grass layer prevailed, while in carabids individuals with granivore strategy gained dominance. Thus, despite the differences in their speed, basically both assemblages tracked vegetation changes. The effect of future fires will depend on their scale, as well as land-use practices, such as grazing, that interact with fire frequency and recovery. If extensive fires in the future permanently change the vegetation, then it would also lead to a fundamental change in the arthropod fauna.
Authors:E. Zsolt Horváth, A. Antal Koós, Krisztián Kertész, Zofia Vértesy, György Molnár, Mária Ádám, Csaba Dücső, József Gyulai and P. László Biró
Gas sensing properties of different carbon nanotube (mostly multiwall,
MWCNT) mats, based on electrical resistance measurement were investigated in a
simple arrangement and found that the sensitivity for different gases or vapors
highly depends on the pre-treatment and functionalization of nanotubes. The
selectivity of the sensing was demonstrated by building a vapor recognition
system based on an array of multitube sensors made of differently