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61.
Aleksandra Bawiec Katarzyna Pawęska Krzysztof Pulikowski 《Water, air, and soil pollution》2017,228(9):366
The aim of the study was to determine the changes in suspension particle size identified in biologically treated wastewater, which was then treated in hydroponic system with use of engineering lighting by the light-emitting diodes (LED). The study was subjected to wastewater purified under laboratory conditions, in a hydroponic system using the effect of macrophytes Pistia stratiotes and growing algae. Measurement of particle size was made using a laser granulometer. Analysis of the results showed that the additional lighting of the hydroponic system with LED can significantly influence the ability of the suspension particles to agglomerate and, consequently, determine their sedimentation properties. In hydroponic system supported by additional lighting, more particles were observed with equivalent diameter D(3.2) smaller than 10 μm than those in the tank without additional lighting, indicating a higher reactivity of the particles. Determining the size of equivalent diameters D(4.3) allowed us to observe that in hydroponic system, particles of relatively small size predominate, which negatively affects the sedimentation process of the suspensions. Determination of particle size of suspensions consisting mainly of algae and the dynamics of their changes are the basis for specification of an effective method of removing particles from the system to protect the receiver from excessive suspension concentrations. 相似文献
62.
Marek Gugała Krystyna Zarzecka Krzysztof Kapela Iwona Mystkowska 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2019,69(2):121-125
The objective of the study was to determine the effect of the experimental factors on the seed quality of three winter oilseed rape cultivars. The following factors were studied: I-three winter oilseed rape morphotypes: population, hybrid restored characterised by a semi-dwarf growth pattern, hybrid restored characterised by a conventional growth pattern; II-two sowing methods: a spacing of 22.5?cm, a spacing of 45.0?cm; III-four types of biostimulants: control-no biostimulants, the biostimulant Tytanit®, Asahi®SL, Silvit®. Seed samples were subjected to chemical analysis to determine: crude oil, total protein and crude fibre. Natural stimulants of plant growth and development contributed to an increase in crude oil ranging from 7.4 to 9.5?g?kg–1 d.m., on average, compared with control. The biostimulants applied did not affect total protein content which was, however, affected by meteorological conditions in individual study years as well as the genetic factor. Biostimulants increased crude fibre content compared with control. 相似文献
63.
Krzysztof Krawczyk Mateusz Szymańczyk Aleksandra Obr?palska-St?plowska 《Journal of insect science (Online)》2015,15(1)
Colorado potato beetle (CPB, Leptinotarsa decemlineata Say) (Coleoptera: Chrysomelidae) is one of the most serious insect pest feeding on wild and cultivated Solanaceae plants. This pest poses a significant threat to potato crops. CPB originated from North America but has become widespread and has adapted in new localizations. Currently, it is reported in many countries worldwide. Endosymbiotic bacteria might have an influence on insect adaptation to new conditions. They are known to play a role in invasiveness of insect hosts and to facilitate colonization of new niches; however, information on endosymbionts of the CPB is very limited. In this study, we screened CPB populations collected from 20 evenly distributed locations in Poland for the presence of Arsenophonus, Cardinium, Wolbachia, and Flavobacterium. We found the presence of Flavobacterium in the studied insects. Little is known about CPB–endosymbionts interactions, thus this study may provide a reference for future studies in this subject. 相似文献
64.
Daniel Żarski Katarzyna Targońska Sławomir Krejszeff Maciej Kwiatkowski Krzysztof Kupren Dariusz Kucharczyk 《Aquaculture International》2011,19(6):1105-1117
Two experiments were conducted into the rearing of crucian carp larvae under controlled conditions in an experimental closed
water system. In both cases, the rearing lasted 21 days. The first experiment concerned the initial stocking density (from
50 to 600 individuals per l), whilst the second one studied the first food offered (two types of Artemia nauplii, decapsulated Artemia cysts and three types of commercial feeds) which were applied at the moment of exogenous feeding commencement. The best results
were obtained using 50 larvae per l, whilst there were no significant differences within the range 200–600 larvae per l. The
application of dry feed had a negative influence on the survival and other parameters. The highest survival rate was found
in the groups fed with freshly hatched Artemia naupli. The results obtained indicate that the rearing of crucian carp larvae may be successfully conducted in very high
stocking densities. However, the very high sensitivity of crucian carp larvae to the type of food offered during the initial
days of life should be taken into account. The data presented in this article could be very useful in crucian carp larviculture. 相似文献
65.
Krzysztof Kołodziejczyk Monika Kosmala Joanna Milala Michał Sójka Małgorzata Uczciwek Bogusław Król 《The Journal of Horticultural Science and Biotechnology》2013,88(6):89-95
SummaryPomaces obtained during the production of cloudy or clear juice from scab-resistant apple cultivars (28 harvested in 2006, and 23 harvested in 2007) were studied as a source of nutritionally important components. It was shown that the average yield of pomace during the production of cloudy juice was 6.4% (w/w), and 4.9% (w/w) for clear juice pressing. The average total dietary fibre (TDF) contents were 48.4% (w/w) and 52.4% (w/w) for cloudy and clear juice pomaces, respectively. Ten pomaces from cloudy apple juice production, and 12 obtained from clear juice production, contained ≥ 2,000 mg kg?1 of polyphenols.‘Ariwa’ and ‘Rajka’ are apple cultivars suitable for juice production and their pomaces are characterised by having high contents of TDF [50.9% (w/w) and 51.1% (w/w), respectively], with aboveaverage polyphenol and quercetin glycoside concentrations. The mean contents of quercetin glycosides for pomaces from all apple cultivars was 994 mg kg?1 after clear juice production, and 908.2 mg kg?1 after cloudy juice production. ‘Topaz’, which became a popular commercial apple cultivar in Europe, was the best source of health-promoting components. Its pomace was the richest source of polyphenols among all 28 cultivars studied. It contained ≥ 2,000 mg kg?1 quercetin glycosides in both its clear and cloudy juice pomaces. 相似文献
66.
Assessment of the usefulness of particle size distribution measured by laser diffraction for soil water retention modelling 下载免费PDF全文
Krzysztof Lamorski Andrzej Bieganowski Magdalena Ryżak Agata Sochan Cezary Sławiński Wioleta Stelmach 《植物养料与土壤学杂志》2014,177(5):803-813
Particle size distribution (PSD) is a major soil characteristic, which is essential and commonly used for the development of pedotransfer functions (PTFs) to estimate the water retention of soils. The laser diffraction method (LDM) became a popular alternative to the standard sieve‐hydrometer method (SHM) of PSD measurement. Unfortunately, PSDs determined with LDM and SHM methods differ sometimes substantially. Moreover, it is claimed that the laser diffraction method underestimates finer fractions in favor of coarser fractions. Several authors have tried to elaborate on methods to recalculate LDM PSD into its SHM counterparts, but no universal methodology has been developed to this date. In this paper, we use PSD determined by LDM directly for PTF development and compare it with the classical PTF approach based on PSD measured by SHM. Four different PTF models based on LDM particle size distribution data were developed, with different PSD characteristics taken as the models' input variables. The possibility of using alternative PSD characteristics, such as deciles, area moment mean and volume moment mean, for PTF development was examined. The accuracy of PTF models constructed on the basis of LDM‐measured PSD was comparable with that of the developed models using texture data obtained from SHM, giving approximately the same RMSE and R2 values. Our study shows that LDM‐measured particle size distribution may be directly used for PTF developments without any recalculations to their sieve‐hydrometer counterparts. 相似文献
67.
Correlations between the behavior of recreational horses,the physiological parameters and summer atmospheric conditions 下载免费PDF全文
Iwona Janczarek Izabela Wilk Edyta Zalewska Krzysztof Bocian 《Animal Science Journal》2015,86(7):721-728
The aim of this paper was to select atmospheric factors and their values, which may disrupt the correct behavior and physiological condition of recreational horses. The studies were carried out from 1 July until 1 September on 16 Anglo‐Arabian geldings. Each day, from 09.00 to 10.00 hours, the horses worked under saddle. The riders and the authors gave a qualitative behavioral assessment for each horse. Mood and willingness to work were evaluated. The quantitative assessment was called ‘incorrect behavior of the horse while riding’ (IBHR). The percentage time of duration and the number of occurrences of the features while riding were calculated. Heart rate, body temperature and respiratory rate were taken at 08.00 hours (resting measurement) and at 10.05 hours (post‐exercise measurement). Air temperature, relative air humidity, wind speed and atmospheric pressure were measured at 08.00 and 10.00 hours. The results showed that adverse changes in the behavior of recreational horses can occur if the horse is ridden when the air temperature is above 26°C and when wind speeds exceed 5.5 m/s. Such conditions may cause a reduction in the mood and willingness to work in horses. Physiological parameters like heart rate and body temperature seem to be more sensitive indicators of the horse body reaction to the weather than behavioral reactions. 相似文献
68.
Krzysztof Górski Stanisław Kondracki Maria Iwanina Władysław Kordan Leyland Fraser 《Animal Science Journal》2021,92(1):e13629
The aim of the study was to determine the relation between the semen quality, frequency of sperm defects, sperm dimensions and shape, and the ejaculate volume of Large White and Landrace boars. A total of 648 ejaculates collected from 31 Large White and 30 Landrace boars were divided into three groups according to the criterion of the ejaculate volume. In this study Landrace boars produced ejaculates with higher volume, sperm concentration, and total numbers of spermatozoa than Large White boars. Landrace boars also showed a lower frequency of sperm with morphological abnormalities (P < 0.05). Landrace boars sperm had larger heads, which were by 0.15 μm longer, and by a larger perimeter and area (P < 0.05). Landrace boar spermatozoa also had a longer flagellum and were generally larger and by 2.07 μm longer than Large White boar sperm (P < 0.05). Significant differences were also found in the shape of sperm of the two breeds (P < 0.05). Landrace boars sperm had more elongated heads, and the ratio of head size to flagellum length was lower than in Large White boars sperm (P < 0.05). Sperm from ejaculates with low volume had a shorter flagellum and a greater head length/flagellum length ratio than sperm from medium- and high-volume ejaculates (P < 0.05). 相似文献
69.
Woclawek-Potocka I Borkowski K Korzekwa A Okuda K Skarzynski DJ 《The Journal of reproduction and development》2006,52(6):731-740
The main purpose of this study was to check whether phyto- and endogenous estrogens influence calcium ion mobilization [Ca(2+)](i) in bovine endometrial cells and whether this action is connected with biological effects i.e. prostaglandin (PG)F(2alpha) production. In our study we used two calcium measurement methods by comparing the microscopic method with widely used quantitative - spectrofluorometric method of [Ca(2+)](i) measurement. We also wanted to confirm whether visualization of calcium ion [Ca(2+)](i) in cells using microscopic method supported by micro image analysis (Micro Image Olympus system) reflects real, qualitative changes in the ion concentration. In both methods a cell-permeable form of fluorescent [Ca(2+)](i) indicator Fura-2 was used. Cultured bovine endometrial epithelial and stromal cells influenced by phorbol-2-myristate-13-acetate (PMA; positive control), estradiol 17-beta (E(2); endogenous estrogen) and active metabolites of phytoestrogens (environmental estrogens) were used as a model to study PGF(2alpha) secretion and [Ca(2+)](i) mobilization in the cells. Equol and para-ethyl-phenol in doses of 10(-8)-10(-6) M increased PGF(2alpha) concentration both in epithelial and stromal cells (P<0.05). In both methods, equol and para-ethyl-phenol did not cause intracellular [Ca(2+)](i) mobilization in epithelial and stromal cells (P>0.05). Both methods revealed that only E(2) and PMA induced intracellular [Ca(2+)](i) mobilization in epithelial and stromal cells (P<0.05). The results of both methods were highly correlated (P<0.001; r=0.82 for epithelial cells and r=0.89 for stromal cells). In conclusion, both methods gave approximately the same results and showed that phytoestrogens, in contrast to PMA and E(2), did not cause intracellular [Ca(2+)](i) mobilization in endometrial cells. The obtained results proved that the [Ca(2+)](i) visualization method supported by micro image analysis can produce similar results to the spectrofluorometric method. 相似文献
70.
Krzysztof Gondek Michał Kopeć Tomasz Mróz 《Communications in Soil Science and Plant Analysis》2018,49(11):1257-1265
Biochar used in this study was prepared from wheat straw and enriched with 10% solutions of chemically pure salts: ammonium sulfate [(NH4)2SO4] and magnesium sulfate (MgSO4 7H2O). The aim of this study was to determine the growth response of Perennial ryegrass L. as well as identify changes in chemical and biological properties of sandy soil after the application of biochar. A significant increase in the amount of Perennial ryegrass L. biomass was determined after amending the soil with unenriched biochar and biochar enriched with (NH4)2SO4. The highest immobilization of available forms of Mg was observed for biochar enriched with (NH4)2SO4. The highest dehydrogenase activity was determined in the soil with biochar enriched with MgSO4 7H2O. 相似文献