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In this work the dynamics of colour changes was examined in apple slices during convectional drying. The drying was carried out at a temperature of 60°C until 10% of moisture content was obtained. During drying, the colour of the tested apples was measured using the L*a*b* system. Three different apple varieties were used for tests (Ligol, Champion and Alwa). Each sample was divided into three parts – the first was dried without preliminary processing, the second was blanched in water at 98°C for 2 min, and the third was blanched in water (98°C, 2 min) with sugar and citric acid added. Based on the results obtained, the rate of changes in all colour parameters during the process was determined. It was concluded that the dynamics of colour changes depends on the variety. The type of preliminary treatment had an influence on the dynamics of colour changes mainly in the case of Ligol variety.
Определения выбранных физических свойств почвы проводились на песчаной почве содержащей 9,9% илистых частиц в период с мая по август. Образцы отбирали из почвы многолетней залежи и черного пара, а также из почвы поля кратко - и долговременного севооборота. Установлено, что в сравнении с почвой полей севооборота длительное удерживание почвы в черном паре приводило к снижению, а удерживание в состоянии залежи к повышению водостойкости почвенных агрегатов. В условиях залежи порозность почвы удерживалась на высшем, а плотность и влажность почвы на более низком уровне, чем почвы полей севооборота и черного пара. Со значениями указанных свойств коррелировали, в общем, значения характерные для плотности почвы.
Since the commencement of political system transformations in Poland the number of farms keeping cows and the stock of milk cows has been decreasing very fast. A basic factor behind the regional diversity of the process is the scale of agrarian fragmentation and the size of farms. This hypothesis was verified by analyzing changes affecting cows bred in a sector of farms operated by natural persons (private farms) in the entire country and in two regions where private farms predominated. The first region is the south-eastern region characterized by a very unfavorable acreage structure of farms while the other one is the central and eastern region where the structure of farms is relatively favorable. Research results clearly indicate that, due to increasing market competition, cow breeding is concentrated and has been moving to higher and higher acreage groups. As a result, strong stock regress has been observed in the region with fragmented agriculture and such trend has been on the increase. However, in the area characterized by the favorable farm structure such regress which marked the commencement of the political system transformations was relatively quickly slowed down; already in the period preceding Poland’s accession to the UE the stock quantity and quality growth emerged which can also be seen during the post-accession era.
The aim of the present study was the description of the dynamics in erythrocyte GSH-Px activity and serum selenium content changes in sows during 14 days before and 14 days after parturition. The experiment was performed on 36 gilts of 1-3 years old. All animals came from the same farm with a closed production system and were fed the same diet of unknown selenium content. Blood was collected 8 times: 13-14 days before parturition, 6-7 days before parturition, 48-72 hours before parturition, and 12-24 hours before parturition, as well as 12-24 hours after parturition, 48-72 hours after parturition, 6-7 days after parturition and 13-14 days after parturition, always after feeding. Blood was centrifuged to obtain serum and erythrocytes were hemolysed. Erythrocyte GSH-Px activity was determined by the Paglia and Valentine method and expressed in U per g Hb. Serum selenium content was determined by the atomic absorption method. GSH-Px activity 14 days before parturition reached 13.38 U/g Hb and significantly decreased around the 7th day before parturition to 11.26 U/g Hb. 72 hours before parturition the activity of the enzyme increased to 16.85 U/g Hb. Between the 72nd hour before and the 14lh day after parturition GSH-Px activity remained constant. Serum selenium content did not differ significantly in the examined gilts and ranged between 88.9 ug/L and 121.87 ug/L. 24 hours before and 24 hours after parturition the selenium content reached 96.55 ug/L and 88.91 ug/L respectively.
Angiogenesis and VEGF play a major role in many repair processes such as healing of gastric ulceration.The present study was undertaken to assess the dynamics of changes in VEGF expression and angiogenesis in stress-induced gastric ulcers in rats. Acute gastric ulceration was induced using a water-immersion and restraint stress method. The VEGF expression, angiogenesis, size of area and depth of ulcers in gastric speciments were evaluated. The study shows that as early as one day after the development of ulcers there is a significant increase in both the expression of the VEGF protein and the number of newly formed microvessels, while an abrupt decrease in VEGF expression, observed on the fifth day, results in a decreased intensity of angiogenesis. Moreover, it has been demonstrated that the increase in VEGF expression and angiogenesis is accompanied by a reduction in the size of area and depth of stress-induced ulcers in rats. Six days after ulcer development both VEGF expression and angiogenesis return to normal levels.
The objective of the presented study was to assess the dynamics of changes of the histological parameters of the following two pork muscles: the semimembranosus muscle (musculus semimembranosus) and the quadriceps muscle of the thigh (musculus quadriceps femoris) under the influence of curing, massaging and pasteurisation processes with the assistance of the computer image analysis. The analysis of the muscle structure was conducted on the basis of: the surface and circumference of muscle fibres, Feret’s H and V diameter, percentage proportion of muscle fibres and their quantity in the analyzed field of view. The fibre shape was determined on the basis of the H/V ratio. It was found that the quadriceps muscle of the thigh exhibited greater dynamics of changes of the structure elements in comparison with the semimembranosus muscle under the influence of injection and plasticizing processes. The injection of ham muscles resulted in the loosening of muscle fibres, rounding of their contours as well as in the increase of their cross section area. The pasteurisation process failed to cause changes in the structure of the quadriceps muscle of the thigh, whereas in the semimembranosus muscle, pasteurisation increased the cross section area and circumference of muscle fibres and their percentage proportion in the examined field of view in comparison with the massaged muscle. The applied pasteurisation process was found to even out cell dimensions and to decrease inter-cellular spaces in both of the examined muscles.
It is found that in Belarus at sufficiently active economic activity directed to weed infestation decrease, in a group of dominant species in winter grain crops remained those resistant to 2,4-D and MCPA – Elymus repens, Tripleurospermum inodora, Pollingonum spp., Galeopsis spp., Viola spp., Sonchus arvensis, Cirsium arvensis, Artemisia spp., Taraxacum spp., Melandrium album, Vicia cracca, Viola spp., Matricaria spp., Stellaria media, Myosotis аrvensis, Spergula sativa, Poa annua, Apera spica-venti, Galium aparine, Artemisia vulgare and etc., in the future the increase of windfallen rape, Galium aparine, Thlaspi arvense, Сapsella bursa-pastoris, Melandrium album, Avena fatua, Papaver rhoeas, Echinochloa crus-galli.
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