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Number of results: 16
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Abstract

ll was proved that the activity of basic proteinases (pH 8.3) and acid proteinases (pH 4.0) of the Antarctic krill increases exponentially in spring-summer season (September-December); the activity of the first ones is 6 times higher and increases more rapidly. The positive relation between the proteolytic activity and the degree of gut filling of krill was also evidenced. The lack of high activity of acid proteinases in early spring does not support the suggestions of Ikeda and Dixon (1982) that during Antarctic winter krill takes energy from the autoproteolysis of own body proteins.
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Abstract

The aim of this study was to determine to what extent the ions present in hard water (125 mg/L of MgCl2 and 500 mg/L of CaCl2) may intensify the feed-induced decrease in oxytetracycline (OTC) absorption rate in broiler chickens after single oral administration at a dose of 15 mg/kg. Drug concentrations in plasma were determined by liquid chromatography-tandem mass spectrometry and combined, compartmental and non-compartmental approach was used to assess OTC pharmacokinetics. The administration of feed decreased the absolute bioavailability (F) of OTC from 12.70%±4.01 to 6.40%±1.08, and this effect was more pronounced after the combined administration of OTC with feed and hard water (5.31%±0.90). A decrease in the area under the concentration- time curve (AUC0-t), (from 10.18±3.24 μg·h/ml in control to 5.13 μg·h/ml±1.26 for feed and 4.26 μg·h/ml±1.10 for feed and hard water) and the maximum plasma concentration of OTC (Cmax) (from 1.22±0.18 μg/ml in control, to 1.01 μg/ml ±0.10 for hard water, 0.68 μg/ml±0.10 for feed and 0.61 μg/ml±0.10 for feed and hard water) was observed. The results of this study indicate that feed strongly decreases F, AUC0-t and Cmax of orally administered OTC. The ions present in hard water increase this inhibitory effect, which suggests that, therapy with OTC may require taking into account local water quality and dose modification, particularly when dealing with outbreaks caused by less sensitive microorganisms.
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Abstract

Observations indicate a constantly decreasing mean age of shoal. In consecutive years of investigations a loss of older individuals was recorded. At present the catches consist of 3—14 years old fishes; 9—10 years old dominate. During the austral summer the fish most probably do not migrate. The shoal of the shelf maintains approximately constant frequency and dominance in classes of length.
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Abstract

The aim of this study was to determine the influence of feed on the pharmacokinetics of flumequine (FLU) administered to broiler chickens as follows: directly into the crop (10 mg/kg of BW) of fasted (group I/control) and non-fasted chickens (group II), or administered continu- ously with drinking water (1 g/L for 72 h) and with unlimited access to feed (group III). Plasma concentration of FLU was determined by high-performance liquid chromatography with fluo- rescence detection. In group II, a significant decrease in the maximum concentration (Cmax = 2.13±0.7 μg/mL) and the area under the concentration curve from zero to infinity (AUC0→∞ = 7.47±2.41 μg·h/mL) was noted as compared to the control group (Cmax = 4.11±1.68 μg/mL and AUC0→∞ = 18.17±6.85 μg·h/mL, respectively). In group III, the decrease in AUC was signifi- cant only in the first 3 hours (AUC0→3 = 5.02±1.34 μg·h/mL) as compared to the control group (AUC0→3 = 7.79±3.29 μg·h/mL). The results indicate that feed reduced the bioavailability of FLU from the gastrointestinal tract by at least 50% after the administration of a single oral dose. However, continuous administration of FLU with drinking water could compensate for the feed-induced decrease in absorption after single oral dose.
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Abstract

The coal fed to gravity enrichment consists of coals coming from different deposits and exploitation fronts. These coals differ in quality parameters, especially the amount of gangue (stone) changing over time. This results in the instability of work, especially jiggers, which have a relatively low accuracy assessed by probable scattering or imperfection rates. This deteriorates the quality of the concentrate obtained, the quality parameters of which change over time. The improvement of jiggers work would be possible by averaging the feed. This process is practically impossible due to the failure to design such a node during plant construction, which are, in most cases, directly related to the shaft. In the article, the authors propose to solve the process of averaging the feed before directing it to the enrichment process in jiggers by introducing its deshaling in vibratory- air separators of the FGX type.
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Abstract

The study was conducted on 26 male, 30 days-old goats, separated from their mothers, divided into two equal groups: I - control and II - experimental, consisting of 13 animals each. All animals were fed with milk replacer, experimental group received additionally 50 g/kg body weight, additive of HMB, for 60 days. The following features were analyzed: body weight, daily increases of body weight, as well as hematological and biochemical blood features. Differences in body weight were found, between experimental and control group, after 60 days of experiment 0.57 kg (p≤0.01). The daily weight gain of experimental animals was higher in comparison with control group. Significant differences were also noted in results of hematological and biochemical blood parameters. Experimental animals showed a higher level of red blood cells as well as number of lymphocytes in comparison with the control group, (p≤0.01).Significant changes were also observed in the level of triglycerides, inorganic phosphorus and protein between both groups. The acid-base balance parameters and ionogram, showed a higher pH level (p≤0.05) HCO – act., HCO – std., BE, ctCO , O sat, K+, Cl– (p≤0.01), while the anion gap (AG) and Na+ were significantly lower in control group (p≤0.01).
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Abstract

We discus legal status of plants obtained using NBT: whether they are to be treated as GMOs or not. The conclusion may have a negative impact on the development of research on them and their practical use. The problem of the application of provisions on GMOs in relation to the products of some of the NBT has been the subject of the decision of the Court of Justice of the European Union (CJEU) in Case C-528/16 – this topic is analyzed in details.
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Abstract

The objective of this study was to investigate the anticoccidial effect of apple cider vinegar added to drinking water with the anticoccidial effect of amprolium to feed broiler chicken. The study has adopted an observational approach to evaluate the anticoccidial effect of apple cider vinegar on broiler chicken. The antioxidative changes were measured adding natural apple cider vinegar to drinking water. Four hundred and fifty broiler chickens were purchased from the local market and distributed into three groups (T+vc: positive control, T-vc: negative control Tv: apple cider vinegar) with 150 chickens in each group. The three groups were further replicated into 3 blocks each containing 50 chickens. The groups were fed balanced diet, amprolium was added to the feed of positive control group, and apple cider vinegar was added to the water of Tv group. Measurements of the different variables were started from week 3, at the end of each week 3 birds were chosen randomly, blood samples were collected via the wing vein, and fecal oocysts were counted from intestinal contents of each individual bird using the McMaster technique. Broiler in the control groups T+ve and T-ve showed clinical signs of coccidiosis (blood in feces) and the number of coccidial oocytes in feces increased with time. In the vinegar group, no clinical signs of coccidiosis were observed. Concentrations of total antioxidants and catalase enzyme activity significantly increased (p≤0.05); while malondialdehyde concentration significantly decreased (p≤0.05).
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Nauka | 2018 | No 3 | 155–173

Abstract

The production of domestic protein for feed in Poland is insufficient. The import of feed raw materials, especially soybean, which is genetically modified (GM) is necessity. In 2016, Poland imported about 2 million tonnes of GM soybean. In Poland was introduced a ban for using and production of GM feed (Law – animal feed from 2006). This ban has already been suspended few times, mainly due to the fact, that the complete replacement of imported GM soybean meal with other components was impossible. The Minister of Agriculture and Rural Development appointed “Team for alternative sources of protein”, responsible for finding solutions that will impact on reducing imports and will increase the share of domestic sources of protein in animal feed. To achieve this aim research are needed to indicate plants and their possibilities for using. The aim of the article is to analyse selected feed components such as: soybean and rapeseed meal, sunflower meal and oilcakes. This analysis concerns the area of cultivation of soybean, rapeseed and sunflower, purchase costs of meals and oilcakes, properties of these components and foreign trade in Poland.
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Abstract

The paper presents the results of research on the impact of impurities in the feed ingots (master heat) on the precipitation of impurities in the ATD thermal analysis probe castings. This impurities occur mostly inside shrinkage cavities and in interdendritic space. Additionally, insufficient filtration of liquid alloy during pouring promotes the transfer of impurities into the casting. The technology of melting superalloys in vacuum furnace prevents the removal of slag from the surface of molten metal. Because of that, the effective method of quality assessment of feed ingots in order to evaluate the existence of impurities is needed. The effectiveness of ATD analysis in evaluation of purity of feed ingots was researched. In addition the similarities of non-metallic inclusions in feed ingots and in castings were observed.
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Abstract

The paper presents the results of research work on the development of a rapidprototyping test stand for testing: servo control algorithms, trajectory generation, algorithms for increasing overall quality of the feed-drive modules within two axis (X-Y) table of the milling machine. Open architecture interface of the prepared control system lets the potential user test functionality of integration of diagnostic tools within the motion controller - directly, without taking into account communication with top-level CNC system.
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Abstract

The paper presents results of studies on linear synchronous motors controlled in CNC feed axes through an intelligent digital servodrive. The research includes a conceptual design of an open servodrive control system and identification of dynamic models of a test stand with an open CNC system. Advantages of robust control over the classic one are discussed. A hybrid predictive approach to robust control of milling machine X-Y table velocity is proposed and results of simulation tests are presented. Was prepared during the work for the Ministry of Science and Higher Education grant number N N502 336936, (acronym for this project is M.A.R.I.N.E. multivariable hybryd ModulAR motIon coNtrollEr), while its main purpose is the development of new rob ust position/velocity model-based control system, as well as to introduce the measurement of the actual state into the switching algorithm between the locally synthesized controllers. Such switching increases the overall robustness of the machine tool feed-drive module. The paper is the extended version of material proposed in [10].
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Abstract

Successful implementation of an active vibration control system is strictly correlated to the exact knowledge of the dynamic behavior of the system, of the excitation level and spectra and of the sensor and actuator’s specification. Only the correct management of these aspects may guarantee the correct choice of the control strategy and the relative performance. Within this paper, some preliminary activities aimed at the creation of a structurally simple, cheap and easily replaceable active control systems for metal panels are discussed. The final future aim is to control and to reduce noise, produced by vibrations of metal panels of the body of a car. The paper is focused on two points. The first one is the realization of an electronic circuit for Synchronized Shunted Switch Architecture (SSSA) with the right dimensioning of the components to control the proposed test article, represented by a rectangular aluminum plate. The second one is a preliminary experimental study on the test article, in controlled laboratory conditions, to compare performances of two possible control approach: SSSA and a feed-forward control approach. This comparison would contribute to the future choice of the most suitable control architecture for the specific attenuation of structure-born noise related to an automotive floor structure under deterministic (engine and road-tyre interaction) and stochastic (road-tyre interaction and aerodynamic) forcing actions.
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Abstract

On the basis of hydrogen peroxide decomposition process occurring in the bioreactor with fixed-bed of commercial catalase the optimal feed temperature was determined. This feed temperature was obtained by maximizing the time-average substrate conversion under constant feed flow rate and temperature constraints. In calculations, convection-diffusion-reaction immobilized enzyme fixed-bed bioreactor described by a coupled mass and energy balances as well as general kinetic equation for rate of enzyme deactivation was taken into consideration. This model is based on kinetic, hydrodynamic and mass-transfer parameters estimated in earlier work. The simulation showed that in the biotransformation with thermal deactivation of catalase optimal feed temperature is only affected by kinetic parameters for enzyme deactivation and decreases with increasing value of activation energy for deactivation. When catalase undergoes parallel deactivation the optimal feed temperature is strongly dependent on hydrogen peroxide feed concentration, feed flow rate and diffusional resistances expressed by biocatalyst effectiveness factor. It has been shown that the more significant diffusional resistances and the higher hydrogen peroxide conversions, the higher the optimal feed temperature is expected.
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Abstract

Optimal feed temperature was determined for a non-isothermal fixed-bed reactor performing hydrogen peroxide decomposition by immobilized Terminox Ultra catalase. This feed temperature was obtained by maximizing the average substrate conversion under constant feed flow rate and temperature constraints. In calculations, convection-diffusion-reaction immobilized enzyme fixed-bed reactor described by a set of partial differential equations was taken into account. It was based on kinetic, hydrodynamic and mass transfer parameters previously obtained in the process of H2O2 decomposition. The simulation showed the optimal feed temperature to be strongly dependent on hydrogen peroxide concentration, feed flow rate and diffusional resistances expressed by biocatalyst effectiveness factor.
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