Authors:J. Pintér, E. Kósa, G. Hadi, Z. Hegyi, T. Spitkó, Z. Tóth, Z. Szigeti, E. Páldi, and L. Marton
The level of UV-B radiation reaching the surface of the earth is increasing due to the thinning of the ozone layer in the stratosphere over recent decades. This has numerous negative effects on living organisms.Some of the Hungarian inbred maize lines examined under the climatic conditions in Chile exhibited an unusually high proportion of pollen mortality, flowering asynchrony and barrenness. The evidence suggests that this can be attributed to the approx. 30% greater UV-B radiation in Chile.The investigation of this problem within the framework of abiotic stress breeding programmes is extremely important in the light of the global rise in UV-B radiation, which may make it necessary to elaborate a selection programme to develop inbred lines with better tolerance of this type of radiation.In the course of the experiment the same ten inbred lines, having different maturity dates and genetic backgrounds, were tested for five years in Chile and Hungary. The tests focussed on anthocyanin, a flavonoid derivative involved in the absorption of damaging UV-B radiation.Averaged over years and varieties, the total anthocyanin content in the leaf samples was significantly higher in Chile than in Hungary. This was presumably a response at the metabolic level to the negative stress represented by higher UV-B radiation.In the five early-maturing flint lines the anthocyanin contents were more than 45% greater than those recorded in Hungary. This suggests that these genotypes, originating from northern regions, were not sufficiently adapted to the higher radiation level. In these samples higher UV-B caused a sharp rise in the quantity of anthocyanin, which absorbs the dangerous radiation. In late-maturing genotypes the initial content of the protective compound anthocyanin was higher at both locations, so in these types the high radiation level was not a problem and did not cause any substantial change.Similar conclusions were drawn from the results of fluorescence imaging. The F440/F690 ratio indicative of the stress level was higher in late lines with a high anthocyanin content, good tolerance and good adaptability.
Authors:J. Pintér, I. Pók, T. Janda, Z. Szigeti, and C. Marton
Solar UV-B radiation is generally regarded as an environmental stress factor, causing harm to living organisms by damaging DNA, proteins, lipids and membranes. Increased UV-B radiation may affect plant life directly or indirectly, having an influence on photosynthesis and plant biomass. In many plants, including maize (which is one of the most important crops in the world), exposure to increased UV-B radiation causes the induction of UV-B absorbing compounds (e.g. flavonoids), which act as UV-B screens and reduce the dangerous levels and effects of this radiation in plant tissues and cells.This study aimed to reveal how Martonvásár maize inbred lines (bred under Central European environmental conditions) respond to increased UV-B radiation.
Authors:Tamás Zsom, Petra Polgári, Lien Phuong Le Nguyen, Géza Hitka, and Viktória Zsom-Muha
of fresh broccoli. Concerning reproducibility of the applied measurements for broccoli quality determination, the increased number of measuring points or the use of computer aided imaging methods (i.e., chlorophyll fluorescenceimaging, machine vision
Authors:Tamás Zsom, Viktória Zsom-Muha, Lien Phuong Le Nguyen, Dávid Nagy, Géza Hitka, Petra Polgári, and László Baranyai
.966, P < 0.001). This change can be easily and objectively determined by the use of a DA-meter®, and by a chlorophyll fluorometer. In Fig. 4 , characteristic chlorophyll fluorescenceimages (1360 × 1024 pixels of resolution) of sweet pepper stored at 2
Authors:M. Patt, A. Schildan, B. Habermann, O. Mishchenko, J. Patt, and O. Sabri
Quantum dots functionalized on the outer surface with either amino- or carboxyl functions were labelled with [18F]fluoroethyltosylate and [11C]methyliodide in order to use the positron emitter-labelled fluorescence agents for multimodality imaging techniques, i.e.
fluorescence imaging and positron emission tomography. 18F-Labelling of both compounds was realized with yields up to 5% as determined by size exclusion chromatography, which is twice
as much as reported in literature before [<cite>1</cite>]. 11C-Labelling of amino- and carboxyl-QDs proceeded with good yields (up to 45 and 35%, respectively) under optimized reaction
conditions. In general for both QD-types and both labelling agents the labelling yield increased with the amount of QDs used
in the reaction as well as with reaction time and reaction temperature.
Authors:Juliane Welke, Michele Hoeltz, Horacio Dottori, and Isa Noll
This study demonstrated the suitability of high-performance thin-layer chromatography using a charge-coupled device (CCD) for acquisition of fluorescence images of ochratoxin (OTA), as a tool for analysis of this toxin in red wine. The mean recovery of the method was 92%. The quantification and detection limits were 0.1 μg L
and 0.32 ng per spot, respectively. Results from validation confirmed the efficiency of the method, which is sensitive enough to be used by producers and governments for quantification of OTA in wine in monitoring and survey programs. The occurrence of OTA in 34 Brazilian red wines was evaluated and one of the samples contained OTA at a level above the quantification limit.
The mission of the U. S. Department of Energy Office of EnvironmentalManagement (EM) is to clean up its contaminated sites from the past productionof nuclear weapons. Within EM, the Office of Science and Technology (OST)is responsible for providing a full range of science and technology resourcesneeded to support resolution of EM cleanup and long-term environmental stewardshipproblems. This responsibility includes implementation of a technology developmentpathway from basic research to development, demonstration, and deploymentof scientific and technological solutions needed by DOE sites. One OST Programis the Characterization, Monitoring, and Sensor Technology Crosscutting Program(CMST-CP), which aims to provide innovative technologies (i.e., faster, better,cheaper, and/or safer) for environmental characterization and monitoring.This paper describes several technologies that CMST-CP has supported for developmentwith significant benefits realized or projected over the baseline characterizationand monitoring practices. Examples of these technologies include mapping ofsubsurface radioactivity using Cone Penetrometer and drilling techniques;a Rapid Liquid Sampler for Sr, Ra, Tc, and Cs using 3M Empore Rad Disks;Long-Range Alpha Detectors; a Compact High Resolution Spectrometer; BetaScintfor determination of Sr in soil; Laser-Induced Fluorescence Imaging techniquesfor mapping U on surfaces; the Environmental Measurements While Drilling System;and the Expedited Site Characterization methodology.