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991.
P. Górka B.L. Schurmann M.E. Walpole A. Błońska S. Li J.C. Plaizier Z.M. Kowalski G.B. Penner 《Journal of dairy science》2017,100(6):4539-4551
The aim of this study was to determine the time course for adaptation of the reticulo-rumen, omasum, abomasum, and small intestine in response to an abrupt increase in the proportion of grain in the diet. Adaptive responses include tissue and digesta mass, small intestinal length, and brush border enzyme activity in the duodenum, proximal jejunum, and ileum. Twenty-five Holstein steers (213 ± 23 kg; 5 to 7 mo of age) were blocked by body weight, and within block were randomly assigned to 1 of 5 treatments: the control diet (CTRL; 92% chopped grass hay and 8% mineral and vitamin supplement on a dry matter basis) or a moderate grain diet (MGD; 50% chopped grass hay, 42% rolled barley grain, and 8% mineral and vitamin supplement) that was fed for 3 (MGD3), 7 (MGD7), 14 (MGD14), or 21 d (MGD21). Dry matter intake was limited to 2.25% of body weight to ensure that changes in dry matter intake did not confound the results. On the last day of the dietary exposure, steers were slaughtered 2 h after feeding. Reticulo-rumen tissue mass and ruminal epithelium mass in the ventral sac of the rumen were not affected by the MGD. Wet reticulo-ruminal digesta mass decreased from CTRL to MGD7 and then increased, but reticulo-ruminal digesta dry matter mass did not differ between treatments. Omasal mass, omasal tissue mass, and omasum digesta mass decreased linearly with the number of days fed MGD, but abomasal tissue mass tended to increase linearly. Duodenal tissue mass tended to increase linearly, and ileal length increased linearly with the number of days fed MGD. Lactase activity in the proximal jejunum increased linearly and maltase activity in duodenum tended to increase linearly with days fed MGD. Aminopeptidase N activity in the proximal jejunum increased cubically with days fed MGD, and dipeptidylpeptidase IV activity in ileum tended to decrease from CTRL to MGD14 and then tended to increase. Adaptation to a diet with a greater proportion of concentrate involves changes in the mass and length of regions of the gastrointestinal tract and brush border enzyme activity. These changes take place gradually over at least 3 wk. 相似文献
992.
Influence of yeast on the yield of fermentation and volatile profile of ‘Węgierka Zwykła’ plum distillates
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Katarzyna Pielech‐Przybylska Maria Balcerek Agnieszka Nowak Piotr Patelski Urszula Dziekońska‐Kubczak 《Journal of the Institute of Brewing》2016,122(4):612-623
The character of plum brandies depends on a unique aroma profile of the plum and the microbiota present on the surface of the fruits, as well as yeast used for fermentation. In this study, an evaluation of the effect of microorganisms applied for the fermentation of W?gierka Zwyk?a var. plum mashes and processing temperature (18 °C, 30 °C) on its efficiency and volatile profile, as well as taste and flavour of distillates obtained was performed. An estimation of the odour activity values (OAVs) of the volatile compounds was also conducted. Regardless of whether the fermentation was carried out using Saccharomyces bayanus wine yeast or by native microflora present on plums as well as raisins, the efficiency of this process was high and ranged between 91.7 and 96.7% of the theoretical efficiency. Especially rich in esters (among others ethyl acetate and isoamyl acetate) was the distillate derived after fermentation with the microflora of plums and raisins, at 18 °C. An evaluation of the individual aromatic effect of chemical compounds present in tested distillates, in terms of their OAVs, revealed that the highest OAVs were reached with isovaleraldehyde. Other compounds that showed aroma values >1 and possibly had an effect on the overall aroma of tested plum distillates were the following: hexanal, benzaldehyde, ethyl acetate, isoamyl acetate, ethyl benzoate, ethyl hexanoate, 1‐propanol, 2‐methyl‐1‐butanol, 3‐methyl‐1‐butanol and 1‐hexanol. The performed sensory ranking showed that the best rated distillate was the one obtained after fermentation with the indigenous microflora of plums and raisins, at 18 °C. Copyright © 2016 The Institute of Brewing & Distilling 相似文献
993.
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995.
Magdalena Anna Kara Sylwia Wdowiak-Wrbel Wojciech Sokoowski 《International journal of molecular sciences》2021,22(17)
Anthropogenic activities generate a high quantity of organic pollutants, which have an impact on human health and cause adverse environmental effects. Monitoring of many hazardous contaminations is subject to legal regulations, but some substances such as therapeutic agents, personal care products, hormones, and derivatives of common organic compounds are currently not included in these regulations. Classical methods of removal of organic pollutants involve economically challenging processes. In this regard, remediation with biological agents can be an alternative. For in situ decontamination, the plant-based approach called phytoremediation can be used. However, the main disadvantages of this method are the limited accumulation capacity of plants, sensitivity to the action of high concentrations of hazardous pollutants, and no possibility of using pollutants for growth. To overcome these drawbacks and additionally increase the efficiency of the process, an integrated technology of bacteria-assisted phytoremediation is being used recently. For the system to work, it is necessary to properly select partners, especially endophytes for specific plants, based on the knowledge of their metabolic abilities and plant colonization capacity. The best approach that allows broad recognition of all relationships occurring in a complex community of endophytic bacteria and its variability under the influence of various factors can be obtained using culture-independent techniques. However, for practical application, culture-based techniques have priority. 相似文献
996.
Piotr Luliński Dorota Maciejewska 《Materials science & engineering. C, Materials for biological applications》2013,33(3):1162-1169
2-(4-Methoxyphenyl)ethylamine imprinted polymers were obtained from seven functional monomers in four porogens, and their properties were tested. Binding experiments revealed the highest selectivity towards a template for the polymer prepared from methacrylic acid in toluene (MIP1). The binding capacities and the imprinting factors were different for the stationary and the dynamic evaluation procedures. For MIP1, the binding capacities were 6.991 ± 0.081 or 18.247 ± 0.005 μmol g? 1, and the imprinting factors were 1.97 or 3.84, for stationary and dynamic procedures, respectively. The Scatchard analysis of MIP1 showed two classes of binding sites with values of the dissociation constants Kd equal to 16.2 and 192 μmol L? 1. Composition of polymers was supported by 13C CP/MAS NMR, FTIR and SEM-EDS analyses. The binding abilities of MIP1 towards the structurally related compounds showed that the ethylamine group together with steric effects governed the recognition mechanism. Finally, the high affinity of MIP1 towards dopamine or serotonin, but low towards norepinephrine and epinephrine was demonstrated. 相似文献
997.
K. Słowik A. Raczyński J. Zaremba S. Zielińska-Kaniasty M. Artoni G.C. La Rocca 《Journal of Modern Optics》2013,60(11):978-987
The cross-Kerr effect is studied for two weak beams, probe and trigger, propagating in an atomic medium in a tripod configuration, dressed by a strong standing wave coupling beam in a regime of electromagnetically induced transparency. The nonlinear phase shifts for both transmitted and reflected probe beams induced by the trigger's presence are found to depend on the probe detuning, the control beam's intensity, the relaxation rates and, in particular, on the redistribution of the population among the atomic levels. Such a quantitative analysis indicates that the transmitted and reflected probe beam components and their respective phase shifts can be easily controlled and optimized. 相似文献
998.
An approximate nonlinear analysis of light generation in two-dimensional square- and triangular-lattice photonic crystal lasers including gain saturation effects is presented for the TE modes. This model extends earlier studies which took into account only TM modes. Our approach is based on coupled mode theory. With the help of an energy theorem and a threshold field approximation an approximate formula relating the small signal gain required to obtain a given output power to the structure parameters has been obtained. It has been used to calculate laser characteristics revealing an optimum coupling strength for which laser structure achieves maximum power efficiency. 相似文献
999.
The paper presents the results of research on the microstructure and mechanical properties of T23 steel after long-term ageing up to 70 000 h at the temperature of 550 and 600 °C. It has been shown that the main mechanisms of degradation of the T23 steel microstructure were: recovery of the matrix, disintegration of the bainitic microstructure, growth of carbide diameter and precipitation of M6C carbides. These processes were more advanced in the steel aged at higher temperature. The changes in the microstructure resulted in a 10–15% decrease in mechanical properties (YS, TS) and hardness HV10, and a 30–40% decrease in the impact energy kV. A greater fall of impact strength occurred in the steel aged at the lower temperature. This was ascribed to the segregation of phosphorus to grain boundaries, which has a well-known adverse effect on ductility of low-alloy steels. 相似文献
1000.