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Yes / Seasonal animals undergo changes in physiology and behavior between summer and winter conditions. These changes are in part driven by a switch in a series of hypothalamic genes under transcriptional control by hormones and, of recent interest, inflammatory factors. Crucial to the control of transcription are histone deacetylases (HDACs), generally acting to repress transcription by local histone modification. Seasonal changes in hypothalamic HDAC transcripts were investigated in photoperiod-sensitive F344 rats by altering the day-length (photoperiod). HDAC4, 6 and 9 were found to change in expression. The potential influence of HDACs on two hypothalamic signaling pathways that regulate transcription, inflammatory and nuclear receptor signaling, was investigated. For inflammatory signaling the focus was on NF-κB because of the novel finding made that its expression is seasonally regulated in the rat hypothalamus. For nuclear receptor signaling it was discovered that expression of retinoic acid receptor beta was regulated seasonally. HDAC modulation of NF-κB-induced pathways was examined in a hypothalamic neuronal cell line and primary hypothalamic tanycytes. HDAC4/5/6 inhibition altered the control of gene expression (Fos, Prkca, Prkcd and Ptp1b) by inducers of NF-κB that activate inflammation. These inhibitors also modified the action of nuclear receptor ligands thyroid hormone and retinoic acid. Thus seasonal changes in HDAC4 and 6 have the potential to epigenetically modify multiple gene regulatory pathways in the hypothalamus that could act to limit inflammatory pathways in the hypothalamus during long-day summer-like conditions. / Biotechnology and Biological Sciences Research Council (BBSRC)

The aim of the diploma thesis was to monitor seasonal concentration changes of 7 antibiotics norfloxacin, levofloxacin, ciprofloxacin, azithromycin, erythromycin, trimethoprim and sulfamethoxazole in wastewater influent and (cleaned) water effluent in the Sewage Treatment Plant (STP) České Budějovice. Time-proportional 24 hours pooled samples of wastewater were collected every month from March 2011 to February 2012 in the influent and effluent pof the STP. The concentrations of target compounds were determined by using in line SPE/LC-MS/MS analysis. The highest average concentration in the influent was detected in case of norfloxacin (0.563 microgram/l) and ciprofloxacin (0.406 microgram/l). The highest average concentration in the effluent was detected in the case of trimethoprim (0.255 microgram/l) and erythromycin (0.117 microgram/l). Higher concentration of antibiotics was measured in the colder periods of the year. It was connected with increased use of antibiotics and with less cleaning efficiency of the STP in this season. The highest removal efficiency was determined for norfloxacin and ciprofloxacin, the lowest for erythromycin. The influence of the season on the removal efficiency of antibiotics was found esp. for azithromycin,trimethoprim and sulfamethoxazole.

Abstract This PhD thesis is composed of a synopsis and five published papers that are focused on both the research results of studies on electrical properties of road materials and subgrade soils and their seasonal changes and the use of Ground Penetrating Radar technique in traffic infrastructure surveys. The data for this survey was collected mainly in Finland, Texas, Scotland and Sweden and thus presents many kinds of road materials, subgrade soils and climate conditions. The synopsis of this work begins with a presentation of the theory and basic principles of GPR techniques. Special attention is given to the dielectric properties and seasonal changes of unbound road materials and subgrade soils. The synopsis also presents different kinds of GPR hardware systems as well as recommendations and experiences from different data collection, processing and interpretation techniques. Special attention is given to a method whereby GPR data is integrated with other road survey data and then analysed using a number of structural diagnostic methods. Finally, the synopsis provides an overview of of the various GPR applications on roads and streets, bridges, railways and airports. The laboratory test results presented in this work show that the relationship between dielectric value and increasing water content is not linear or exponential but more likely a series of logarithmic functions. Laboratory results also showed that dielectric dispersion, which can be related to poorly performing subgrade soils and road aggregates, takes place mainly in loosely bound adsorption water and capillary water layer. As such these moisture sensitive problem materials can also be identified during the dry summer seasons when they are stiff. Dielectric value and electrical conductivity can also be related to other technical properties of road materials and subgrade soils such as frost susceptibility, shear strength, plastic limit, compaction degree and voids content. Laboratory tests and field data collected using the Percostation technique also demonstrate that a knowledge of seasonal changes and thermodynamics is very important in understanding and modelling the mechanical behaviour of road structures. Finally, laboratory and field tests indicate that colloids have an important role in the failure mechanism of the road materials. This research demonstrates that the GPR technique not only gives valuable structural information on the different types of structures and subgrade soils but it provides a wide range of information of the electrical properties of the materials under survey which can be further related to their mechanical performance. The best information will be gained if GPR data is analysed together with other non destructive testing data collected form the roads, railways and airports.

The seasonal changes in freezing resistance and water relations in four dwarf shrub species of Ericaceae family: Vaccinium vitis-idaea, V. myrtillus, V. uliginosum and Oxycoccus palustris in two study areas differing in altitude were studied in this work. To establish the freezing resistance, the plants were sampled eight times, to determine parameters of the water relations, the plants were sampled six times during the growing season of 2009. For the freezing resistance examination, ice nucleation temperature (exotherm) and 50 per cent lethal temperature (LT50) were found. The water relations were described using the parameters derived from the pressure-volume curves: osmotic potential at full turgor, osmotic potential at zero turgor, cytoplasmic water fraction, relative water content at turgor loss and bulk modulus of elasticity. An important seasonal variability in the freezing resistance was found. The highest levels of the freezing resistance were reached in the spring and in the autumn, the lowest levels were found in the summer. There were also changes in the used mechanisms of the freezing resistance - for most of the year, the plants were tolerant, they showed the avoidance mechanism only in the summer. The seasonal changes in the water relation parameter were less unambiguous. The most of...