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Dziś wiemy, że wśród około 3 tysięcy gatunków drzew i krzewów, na których uprawę pozwalają warunki klimatyczne Polski, większość stanowią te obcego pochodzenia, trudno zatem wyobrazić sobie, jak mało zróżnicowana była szata roślinna naszego kraju przed kilkoma wiekami. Mimo szerokiego obecnie doboru gatunków i odmian możliwych do uprawy w Polsce, wciąż konieczne jest jego poszerzanie o nowych przedstawicieli flory innych państw. Poszukujemy przykładowo roślin wykazujących dużą odporność na zanieczyszczenia albo o pokroju koron pasującym do wąskich ulic w miastach. To tylko niektóre przyczyny przemawiające za wprowadzaniem nowych gatunków i odmian, ale najważniejszym argumentem jest potrzeba tworzenia coraz bardziej urozmaiconych terenów zieleni.
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.
Most of the strategies developed to reduce weaning diarrhea and to improve the health and performance of pigs are targeted at the post-weaning period and concern modifications of feed composition and/or supplementation with a variety of feed additives. Studies on the physiology of gastrointestinal tract development, however, clearly demonstrated a conflict between the immaturity of the gut mucosa and early weaning. A kidney bean lectin preparation (Suilectin™, Biolek, Poland) was designed to speed up the maturation of the pig gastrointestinal mucosa before weaning. The aim of the present study was to examine the effectiveness of Suilectin™ under practical conditions. The study was performed in a single farm on the total of 3575 piglets, some of which orally received a single dose of Suilectin™ when they were 10-12 d of age (3.27 ± 0.04 kg body weight, BW). Piglets were weaned when they were 25-26 d of life. Their body weight, food intake, clinical health, and veterinary costs were calculated. Suilectin™-treated pigs were characterized by a higher BW at weaning, a lower incidence of post-weaning diarrhea, lower costs of veterinary treatment, and lower mortality as compared to control.
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Birch pollen grains are one of the most important groups of atmospheric biological particles that induce allergic processes. The fluctuation pattern of birch pollen seasons in selected cities of Poland is presented. Measurements were performed by the volumetric method (Burkard and Lanzoni 2000 pollen samplers). The distributions of the data were not normal (Shapiro–Wilk test) and statistical error risk was estimated at a significance level of α = 0.05. Pollen season was defined as the period in which 95% of the annual total catch occurred. The linear trend for the selected features of the pollen season, skewness, kurtosis and coefficient of variation (V%) were also analyzed. During the 12–14 years of study, the beginnings of birch pollen seasons were observed 7–14 days earlier, the ends were noted 5–10 days earlier, and the days with maximum values occurred 7–14 days earlier compared to the long-term data. The left-skewed distribution of the pollen season starts in most sampling sites confirms the short-lasting occurrence of pollen in the air. The threat of birch pollen allergens was high during the pollen seasons. If vegetation is highly diverse, flowering and pollen release are extended in time, spread over different weeks and occur at different times of the day. Flowering time and pollen release are affected by insolation, convection currents, wind, and turbulence. Therefore, pollen seasons are characterized by great inter-annual variability.
The aim of the study was to determinate whether Artemisia campestris was present in the vicinity of 8 pollen monitoring stations in Poland by examining temporal variations in daily average airborne Artemisia pollen data recorded by Hirst type volumetric traps. Three day moving averages of airborne Artemisia pollen were examined by Spearman’s rank correlation test. Results show that Artemisia pollen seasons in Poland generally display similar unimodal patterns (correlation coefficients r > 0.900; P < 0.05). The only exception was the Artemisia pollen concentration noted in the outskirts of Poznań (Morasko), where the bimodal pattern was revealed. Correlations between Artemisia pollen data recorded at Poznań-Morasko and the other Polish sites were the lowest in the investigated dataset; this was particularly noticeable in the second part of pollen season (r ~0.730). We show that the typical bimodal pattern in Artemisia pollen seasons, which is characteristic of the presence of both A. vulgaris (first peak) and A. campestris (second peak), does not occur at the majority of sites in Poland and is restricted to the outskirts of Poznań. In fact, it was noted that the pollen monitoring site in Poznań-Centre, just 8 km from Morasko, only exhibited one peak (attributed to A. vulgaris). This shows that the influence of A. campestris on airborne pollen season curves is limited and can be largely disregarded. In addition, this study supports previous records showing that the spatial distribution of airborne Artemisia pollen within a city (urban-rural gradient) can vary markedly, depending on the species composition.
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