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The paper is focused on the influence of air distribution in modern large university lecture hall on the thermal comfort. Providing the optimal parameters of the thermal comfort in the interiors of a university is immensely important for the students. Meeting these parameters is inevitable not only from physiological point of view but also to achieve the desirable students' performance. Parameters of the thermal comfort are also influenced by air distribution system in large university lecture hall. Correct position of supply air and extract air is very important. Experimental measurements of thermal comfort were carried out in the winter season in the large lecture hall of Vienna University of Economics and Business. The device Testo 480 was used for the measurements. Obtained values of air temperature, air relative humidity, air velocity, globe temperature, indexes PMV and PPD are presented in the charts. Modern air distribution system and air conditioning system of the large university lecture hall were evaluated on the basis of thermal comfort parameters. Conclusion of this paper states the principles of how to design modern air distribution systems and air conditioning systems in the new large university lecture halls.

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In food science, colour is a fundamental property for the evaluation of freshness, quality and conformity. One of the most important attributes indicating sweet cherry freshness is stem colour and shape. Fruit post-harvest cool storage retards respiration and colour ripening changes. The common technology of refrigeration is based on active cooling determining high evapotranspiration for the passage of air over the products surface. An innovative preservation system, such as the Passive Refrigeration System (PRS™), could guarantee perfect shelf-life preservation maintaining optimal temperature and relative humidity close to 100%, minimizing colour changes in medium-long storage range. There is the need to numerically quantify cherry stem thickness and colour changes to compare fruit postharvest conditions under the two systems. The use of the Thin-Plate Spline 3D warping (TPS3D) in the 3-dimensional-RGB colour space allowed an efficient colour calibration. Sweet cherry stem images belonging to the two different storage systems (active and passive refrigeration) were acquired before and after 7 days to preservation through a professional high resolution scanner. Thickness and colour (after calibration) were measured. Results indicate, in terms of sweet cherry quality of preservation, that the ones preserved in passive refrigerator after 7 days appears similar to the fruits at the beginning of the experiment.

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The relationship between water body (fountains) scale and climate parameters like wind speed, air temperature, relative humidity, as well as thermal comfort index was modeled and analyzed via Envi-met code. Taking the water impact and factors analysis as a research object, the factors mainly discussed in this research are square area to water-body area ratio and the location of the water element. However, the computational fluid dynamics simulations were conducted on the following scenarios: 3% (original base case), 6%, and 9% of the total square's area, then the outputs of the two simulation results were compared to the original base case. The results revealed that water scale has a slight effect on the micro-climate of the built environment in the summertime in moderately warm-wet climate zone. However, it is beneficial to adjust temperature and humidity in public spaces of central European cities. Nonetheless, the main aim of this paper is to quantitatively investigate the impact of the water bodies on the urban weather parameters and human thermal comfort under the influence of different scale ratios in Pecs-Hungary.

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Aspergillus niger was found to be the predominant pathogen associated with black mould rot of onion during storage. Market survey for the assess­ment of spoilage caused by the fungus recorded a loss of 2.9% to 12.09% during the period from June 1998 to February 1999. Application of higher doses of calcium in the form of gypsum (400 kg/ha) and lower dose of nitrogen in the form of urea (50 kg/ha) to the field and advancing the harvest of onion bulbs by fifteen days significantly reduced the spoilage of bulbs during storage. An inverse relationship existed between neck length of the bulbs and spoilage at storage. Bulb rotting was noticed when the storage temperature was between 30 °C and 40 °C and the relative humidity was above 80%. Further, A. niger infection caused reduction in pungency of onion bulbs which was more pronounced at grade 4 than grade 1. The culture filtrates of Aspergillus niger and Asper­gillus flavus isolated from onion as well as the extracts from onion bulbs infected with the above fungi were free from aflatoxin contamination.

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The periodicity of insect activity is affected by endogenous and exogenous factors, and these factor thresholds often limit its activity. The flight activity within 24 h circadian rhythm is often influenced by light, whereas the abundance is affected by temperature. This study aimed to hourly follow the flight activity of the peach (PFF) and Mediterranean (MFF) fruit flies, at guava orchard, using sexual and olfactory attractants. The flight of PFF males usually started before that of females, whereas that of MFF males was in the same time as females. As temperature rose above 30 °C, the flight activity of males affected, but that of females not. Thus, flight activities of males were negatively, and females were positively, correlated with temperature. On the contrary, males were positively, and females were negatively, correlated with relative humidity. The sexual attractant attracted more PFF males than MFF, but the olfactory attractants attracted more PFF females than MFF. The highest male captures were between 7:00 am and 10:00 am, and females between 11:00 am and 5:00 pm, suggesting males fly actively during the morning to locate their mates, whereas females fly actively during the afternoon to locate their food and/or distribute their eggs. This also suggests that PFF and MFF are diurnal species. For management of both species, the spray treatments therefore should be taken during the time interval 7:00 am and 10:00 am for males (to disrupt mating) and 11:00 am and 5:00 pm for females (to disrupt feeding and oviposition).

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Among sucking insect pests, the incidence of a leafhopper [Amrasca biguttula biguttula (Ishida)] and a whitefly [Bemisia tabaci (Gennadius)] remained active through the cropping season in varying population density. Thrips [Thrips tabaci (Lindemann)] population was only observed in early stages of the crop growth. The leafhopper population attained its peak during 2nd half of July and was maximum (9.2 nymphs/3 leaves) in the year 2008. The population of whitefly adults was maximum (14.8 adults/3 leaves) in 2007 and it acquired its peak during end of July and again in end of September to early October. The incidence of thrips was maximum in June. The population of the A. biguttula showed significant positive correlation with minimum temperature (r=0.636; p=0.003), mean temperature (r=0.475; p=0.034), evening relative humidity (r=0.618; p=0.004) and rainfall (r=0.556; p=0.011). The correlation of B. tabaci population with minimum temperature was significantly positive (r=0.454; p=0.044). The multiple regression analysis revealed that all the weather parameters collectively accounted for variability in the A. biguttula and B. tabaci population with R2 values ranging from 0.67–0.80 and 0.50–0.69, respectively, during different years.

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Sensory and physicochemical changes of three apple cultivars (‘Golden Delicious’, ‘Idared’ and ‘Gloster’) were monitored during 14 weeks of storage at 6 °C and 70% relative humidity in three following years. The aim was to investigate physicochemical parameters that were best correlated with sensory evaluation of apples during their storage. Sensory quality was assessed using a category point scale and the sensory profile was evaluated using a graphical unstructured scale. Physicochemical changes, such as weight, soluble solids, titratable acidity, and dry matter content, were monitored. All the examined parameters changed during the observed period, with the greatest changes occurring in weight, texture, and taste. There were also differences between the tested cultivars. Statistically significant correlations between sensory and physicochemical data were observed between texture characteristics and weight changes. In case of sweet taste, only a weak correlation between the intensity of sweet flavour and soluble solid content values was found. No statistically significant correlation between the intensity of sour taste and titratable acidity was observed.

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The development of high performance insulating materials incorporating nanotechnologies has enabled considerable decrease in the effective thermal conductivity. Besides the use of conventional insulating materials, such as mineral fibers, the adoption of new nano-technological materials such as aerogel, vacuum insulation panels, graphite expanded polystyrene, is growing. In order to reduce the thermal conductivity of polystyrene insulation materials, during the manufacturing, nano/micro-sized graphite particles are added to the melt of the polystyrene grains. The mixing of graphite flakes into the polystyrene mould further reduces the lambda value, since graphite parts significantly reflect the radiant part of the thermal energy. In this study, laboratory tests carried out on graphite insulation materials are presented. Firstly, thermal conductivity results are described, and then sorption kinetic curves at high moisture content levels are shown. The moisture up-taking behaviour of the materials was investigated with a climatic chamber where the relative humidity was 90% at 293 K temperature. Finally, calorific values of the samples are presented after combusting in a bomb calorimeter.

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Acta Veterinaria Hungarica
Authors: Lydia Gil, S. Saura, Arantxa Echegaray, Felisa Martinez, I. de Blas, A. Akourki, Noelia Gonzalez, E. Espinosa, and A. Josa

The present study evaluated the effect of supplementing the medium used to mature equine oocytes in vitro with oestrous mare serum (EMS) or horse follicular fluid (HFF). To this end, 144 ovaries were obtained from mares aged 16-21 months and transported to the laboratory in Dulbecco's phosphate buffered saline (D-PBS) at 30°C. Oocytes were harvested from the ovaries by slicing, and then selected for in vitro maturation (IVM) according to the number of cumulus cell layers and the characteristics of the cytoplasm. The selected oocytes were washed three times in TCM199 medium plus HEPES (TCM-199H) or in the same medium plus glutamine (TCM-199G), then matured in vitro in six study groups established according to the in vitro maturation (IVM) treatment to see possible interactions between HEPES and glutamine on other supplements: Ten percent EMS was added to two of these media (TCM-199H+EMS and TCM-199G+EMS) and 10% HFF was added to the media in two other groups (TCM-199H+HFF and TCM-199G+HFF). IVM was performed at 38.5°C for 40 h in a controlled atmosphere (5% CO2, 95% relative humidity). The findings indicate that the presence of EMS or HFF in the TCM-199H medium gives rise to the best results in terms of the proportions of oocytes reaching maturity (37.7% and 36.8%, respectively). The values obtained with EMS and HFF were statistically similar to each other but differed from the other treatments. The media containing glutamine led to the highest proportions of degenerated oocytes.

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How are bryophyte alpha and beta diversities distributed across spatial scales along an elevational gradient in an oceanic island? Which mechanisms and drivers operate to shape them? Starting from a multiscale hierarchical sampling approach along an 1000 m elevational transect, we used additive diversity partitioning and null modeling to evaluate the contributions of the alpha and beta diversity components to overall bryophyte diversity in Terceira Island, Azores. Substrate-level diversity patterns were explored by means of the Sørensen Similarity Index and the Lloyd Index of Patchiness. Elevation-level beta diversity was decomposed into its replacement and richness differences components, with several environmental variables being evaluated as diversity predictors. Bryophyte diversity proved to be primarily due to beta diversity between elevation sites, followed by diversity among substrates. Compositional differences between neighboring sites decreased with elevation, being mainly caused by species replacement and correlating with differences in relative humidity and disturbance. At the substrate level, we found a great homogeneity in terms of species composition, coupled with a low substrate specialization rate. We conclude that, in Terceira’s native vegetation patches, regional processes, such as environmental gradients associated with elevation, play a greater role in shaping bryophyte diversity than local processes. Moister and less disturbed areas at mid-high elevation harbor a richer bryoflora, consistently more similar and stable between neighbouring sites. Simultaneously, the different substrates available are somewhat ecologically redundant, supporting few specialized species, pointing to these areas providing optimal habitat conditions for bryophytes. Our findings provide a better understanding of how bryophyte diversity is generated in Terceira Island, indicating that management and conservation measures should focus on island-level approaches, aiming to protect and rehabilitate additional natural vegetation patches at different elevations, especially in the severely disturbed lowlands.

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