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Airborne fungal spores were monitored in 2001-2002 in Rzeszów (town) and its neighborhood. The aim of investigations was to ascertain if there were differences in diurnal variations of airborne fungal spores concentration between town and rural area. The sampling was carried out using volumetric method. Traps were located at the same heights - app. 12 m. Airborne spores were sampled continuously. Microscopical slides were prepared for each day. Analysis was carried out on one longitudinal band of 48 mm long divided into 24 segments corresponding following hours of day. The results were expressed as mean number of fungal spores per cubic meter per 24 hours. For this survey, five geni of allergenic fungi were selected: Alternaria, Botrytis, Cladosporium, Epicoccum, Ganoderma. The concentrations of their airborne spores were high or very high. It was calculated theoretical day, where the hourly count was the percentage mean of number of spores at that time every chosen day without rainfall from 2001 and 2001 years. The diurnal periodicity of Alternaria, Cladosporium, Epicoccum and Ganoderma showed one peak, while Botrytis two. Anamorphic spores peaked in the afternoon, while their minima occurred in the morning. The highest concentrations of Ganoderma basidiospores were at down or at night, but minima during the day. There were no clear differences in the peak values between two studied sites. The results indicate that maximum concentrations of all spores generally occurred a few hour earlier in the rural area than in the town. Probably, in the rural area airborne spores came from many local sources and their diurnal periodicity reflected rhythm of spore liberation. Towns are characterized by specific microclimate with higher temperature and wind blowing to the centre. In Rzeszów fungal spores could be transported outside and carried out by wind from distant sources. This study showed, among others, that habitat conditions are an important factors influenced diurnal periodicity of airborne fungal spores.
The co-occurrence of airborne allergenic pollen grains and fungal spores was estimated in Rzeszów in the years 2000- 2002. The volumetric method was used in this aerobiological study. Six taxa of pollen grains and fi ve types of fungal spores characterized by strong allergenicity and/or high concentrations in the air were analyzed. The time series of pollen grains and fungal spores were compared using PCA analysis. The periods of the greatest concentrations of tree pollen did not coincide with similar periods for herbaceous plants and fungal spores. From February to mid-March, Alnus pollen dominated in the air. The second period was characterized by Betula pollen. It occurred in April. Herbaceous pollen and fungal spores occurred in the air simultaneously (from mid May to the end of August), creating a risky situation for sensitized people. The periods of the highest concentrations of Epicoccum and Ganoderma fungal spores did not coincide with the same period for the examined plant taxa. In Rzeszów the probability of becoming exposed to very high concentrations of allergenic pollen and fungal spores at the same time was high, especially in July, when the highest concentrations of Poaceae, Alternaria and Cladosporium were noted. The hypersensitivity to only one plant or fungal allergen is rarely encountered. Under the present scenarios of global warming, pollen seasons of many taxa will be longer and sufferers will have year-long symptoms.
The global rise in air temperature has major implications for ecosystems, populations, ecology of many living organisms, public health as well as economy. Plants, like silver birch (Betula pendula Roth.), strongly respond to the climatic variation. Therefore, the species is a good indicator of the global climate change, especially warming. The phenological observation was undertaken to verify the hypothesis on an acceleration of the start of Betula pendula pollen release in the season. The investigations were carried out in 2000-2015 (16 years) in the Rzeszów area, SE Poland. On average, Betula pendula started to pollinate in the middle of April; the difference between the earliest and latest dates was nearly 1 month. The full pollination started on 18 April, on average. The timing of pollination strongly depended on the course of weather in February and March. The most crucial was temperature in the first half of March. Considering the synergistic impact of meteorological parameters, the most important were temperature and rainfall in January and February, rainfall in March and temperature just before the pollination. It was found that North Atlantic Circulation influenced pollen release in Betula pendula. The positive North Atlantic Oscillation in March and in December-March periods resulted in pollination onset. Tendency towards warmer average annual temperature was recorded, however the timing of phenophases did not follow it. Despite the strong relationship with temperature there was no acceleration of Betula pendula pollination. Probably, the climate warming effect on the onset and duration in Betula pendula phenophases would be detectable in longer than a 16-year period.
The diurnal pollen pattern of Artemisia seems to be similar in many regions in Central and Eastern Europe, with its highest concentration before noon. This research is a continuation of a preliminary study that was carried out in Rzeszów 10 years ago. The Spearman nonparametric correlation test and the angular-linear correlation were used to verify assumptions about the influence of meteorological parameters on daily and hourly variations of Artemisia pollen concentrations in the atmosphere. The results showed that the patterns of hourly and daily Artemisia pollen concentration in the air of Rzeszów did not differ significantly from the results obtained in previous years, except PI value which was significantly lower. The majority of Artemisia pollen grains appeared in the air before noon and in the early afternoon. However, on some days the peaks occurred around midnight. The hourly and daily Artemisia pollen concentrations were strongly influenced by temperature and relative humidity. Daily concentration was also influenced by radiation and sunshine duration. We do not exclude other factors, such as secondary deposition and long distance transport. We proposed circular statistics as an appropriate method of analysis of the relationship between meteorological parameters and hourly airborne pollen concentration.
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The time pattern of flowering significantly affects the pollen season, its beginning, length and the concentration of pollen grains in air. The forecasting models used in aerobiological studies were chiefly based on the elements of weather conditions; however, recently the phenology of pollen shedding has been taken into consideration in these models more and more frequently. The aim of the presented investigations was to determine to what extent the flowering and the occurrence of allergenic pollen grains in air coincided in time. The investigation was carried out in Rzeszów (SE Poland) in the years 2003-2004. The flowering of 19 allergenic plant species was observed and seven phenophases were distinguished. Aerobiological monitoring was based on the volumetric method. In the case of most herbaceous plants, the flowering period overlapped the pollen season, high concentrations of pollen being recorded throughout several phenophases. In general, the pollen of trees occurred during very short periods, frequently during one phenophase, while the investigated phenomena were missing each other. The most intensive growth of inflorescences of alder, hazel and birch was observed at the beginning of full flowering or towards the end of full flowering.
Studies of the concentration of fungal spores were carried out in the cities of Lublin and Rzeszów simultaneously in 2002. At both sites the volumetric method of measurement was applied, using the Lanzoni VPPS 2000 trap. Only the allergenic taxa were analysed: Alternaria, Botrytis, Cladosporium, Drechslera type, Epicoccum, Torula, Stemphylium, Pithomyces, Polythrincium, and Ganoderma. The research showed considerable differences in the concentration and frequency of spores in the air at the sites compared. Higher mean concentrations of spores were usually observed in Lublin. Only for two taxa were the concentrations higher in Rzeszów. No significant differences were observed for the genus of Polythrincium and Torula. Also the lengths of periods of occurrence of the spores were determined using the 95% method. It was determined that the geobotanical conditions in Rzeszów have a positive effect on the lengthening of the presence of the spores in aeroplankton. The results of the observations were analysed statistically, which confirmed the occurrence of significant differences between the cities compared.
The aim of the study was to compare phenological observations of pollen seasons of selected early spring trees. Special attention was paid to meteorological conditions which favored or did not favor tree flowering and pollen release. For this reason, we used phenological observation, pollen counts, and meteorological data in five sites in the center of Kraków in the period 2009-2011. Phenological phases (5) of four tree species: Alnus glutinosa, Alnus incana, Corylus avellana, and Betula pendula, were analyzed. It was found that in case of A. glutinosa the pollen season often preceded the flowering period, while for A. incana those two phenomena were more correlated. As regards Corylus avellana, the beginning of the pollen season and phenological phases was simultaneous. However, pollen grains occurred in the air longer, even by a dozen or so days. The phenological phases and pollen seasons of Alnus and Corylus were dependent on meteorological conditions. To give the definition of the relationship between pollen concentration and weather conditions, Spearman rank correlation analysis was applied. High Alnus and Corylus pollen concentrations were found on sunny days with a maximum temperature over 10°C and no precipitation, and when the snow cover was gone. In case of Betula, the phenological phases of the full pollination period usually coincided with the periods of high pollen concentrations. However, Betula pollen sometimes appears earlier and stays in the air longer than the flowering period of local trees in the nearest vicinity. This situation indicates long-distance transport or secondary deposition.
Rozwój biotechnologii i upowszechnienie się produkcji preparatów enzymatycznych przy zmniejszających się kosztach produkcji spowodowały, iż enzymy są powszechnie stosowane w praktyce produkcyjnej do kształtowania właściwości funkcjonalnych, odżywczych i organoleptycznych żywności. Wśród preparatów enzymatycznych stosowanych w technologii żywności największą grupę stanowią proteinazy, następnie amylazy i lipazy. W artykule zaprezentowano przegląd preparatów enzymatycznych wykorzystywanych w przemyśle rybnym. Na tym tle przedstawiono wybrane zagadnienia związane z technologią zastosowania transglutaminazy do produkcji wyrobów rybnych. Zastosowanie enzymu umożliwia otrzymanie wysokiej jakości produktów o prawidłowej teksturze, także z surowca niższej jakości.
Poszukiwanie nowych rozwiązań technologicznych wpisujących się w trendy wytwarzania żywności bezpiecznej, długo zachowującej świeżość i jak najbardziej przypominającej produkty świeże, skłania producentów do udoskonalania metod przechowywania i pakowania produktów. Rozwój technik pakowania w atmosferze modyfikowanej MAP pozwala ograniczyć straty związane z psuciem żywności, a także dotrzeć do szerszego grona konsumentów. Technologia ta pozwala pakować zarówno produkty świeże, jak i przetworzone, ograniczając tym samym ilość szkodliwych substancji dodawanych do konserwowania żywności.
Obecnie chłodnictwo odgrywa bardzo ważną rolę w zaopatrzeniu w żywność - gwarantuje wyjściową jakość produktów spożywczych, co powoduje, iż konsumenci otrzymują produkty zdrowe i bezpieczne. Przechowywanie w komorach chłodniczych zajmuje od wielu lat główne miejsce pośród sposobów utrwalania płodów rolnych i gotowej żywności. W artykule zaprezentowano przegląd zagadnień technicznych dotyczących komór chłodniczych. Na tym tle przedstawiono wybrane zagadnienia związane z nowoczesnymi technologiami stosowanymi w chłodniczym przechowywaniu owoców.
13 grudnia 2014 r. zacznie obowiązywać rozporządzenie Parlamentu Europejskiego i Rady (UE) nr 1169/2011 w sprawie przekazywania konsumentom informacji na temat żywności. Od 13 grudnia 2016 r. nałoży ono na producentów obowiązek zamieszczania na opakowaniu informacji o wartości energetycznej i odżywczej. Oznacza to duże zmiany dla wielu branż przemysłu spożywczego. Nowe przepisy ujednolicają wymagania dotyczące etykietowania. Na etykietach projektowanych zgodnie z nowymi przepisami pojawią się nowe dane. Informacje te mają służyć ochronie zdrowia konsumentów i ułatwić im dokonywanie świadomych wyborów.
The occurrence of the Chinese mussel Sinanodonta woodiana (Lea) was discovered in June and July 2011 in a fish pond located about 15 km north-west of Rzeszów (Subcarpathian region). Thirty six specimens (6 dead and 30 live) of the species were found. The Chinese mussel was absent in two other fish ponds in the same area, however the swan mussel Anodonta cygnea (L.) was found in these ponds (80 individuals: 45 dead and 35 live). At the time when the survey was conducted the ponds had already been drained for 3 to 8 months, so both populations will probably disappear from the locality. Nevertheless the new finding of the Chinese mussel in fish ponds confirms the possibility of occurrence of the species also in the waters with natu- ral thermal regime.
Wśród stosowanych metod utrwalania żywności chłodnictwo zajmuje priorytetową pozycję.Ta technika utrwalania umożliwia zachowanie oryginalnych cech i właściwości żywności. W artykule zaprezentowano zagadnienia dotyczące technik chłodniczego i zamrażalniczego przechowywania produktów. Na tym tle przedstawiono wybrane zagadnienia związane z nowoczesnymi rozwiązaniami technicznymi stosowanymi w przetwórstwie.
W artykule omówiono zamienniki tłuszczu stosowane w produkcji żywności. W czasach epidemii otyłości i chorób cywilizacyjnych wzrasta produkcja żywności o obniżonej zawartości tłuszczu. Niskoenergetyczne odpowiedniki produktów tradycyjnych można znaleźć prawie we wszystkich grupach żywności. Zmniejszenie zawartości tłuszczu wymaga poszukiwania rozwiązań pozwalających uzyskać produkt o cechach najbardziej zbliżonych do tradycyjnego, ponieważ tego oczekują konsumenci. Szczególną grupę produktów stanowią lody – obniżenie ich wartości energetycznej przysparza producentom trudności.
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