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This paper examines the relationship between innovation performance and employment growth in firms by taking a closer look at specific innovation activities and industry effects in the context of the services sector. Firm-level CIS data on Polish services firms in 2004–2009 are analysed using robust M-estimation. The results indicate that the effects of product, process and organisational innovations depend strongly on the level of technological opportunities in the industry in question. Given the widely acknowledged role of marketing innovations in services, possible synergies between innovations in the form of new products and new marketing techniques are also analysed. We demonstrate that marketing innovations are conducive to firm growth if they complement product innovations, but they are less likely to foster growth when applied in isolation. 相似文献
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The decrease of lasalocid residue in the edible tissues by silymarin supplementation of chicken diet
Lidia Radko Wojciech Cybulski 《Food additives & contaminants. Part A, Chemistry, analysis, control, exposure & risk assessment》2019,36(5):722-728
Widespread use of coccidiostats, in spite of beneficial control of protozoan infections in poultry, implies a risk of residues in edible tissues, and there is increasing interest in the development of strategies for prevention of veterinary drugs residue in food-producing animals. The aim of this study is assigned to clarify the impact of silymarin addendum in the diet on lasalocid concentration in the liver and breast muscles from the broiler. Four groups of chickens received a feed with lasalocid at levels between 75 and 200 mg kg?1. Other four groups received a feed with lasalocid (75–200 mg kg?1) plus silymarin. Significant differences of lasalocid concentrations between the liver and breast muscles were observed. Moreover, the chickens from the groups supplemented with silymarin shown significant decreases of lasalocid concentrations in the analysed tissues. The herbal substance did not counteract the ionophore in the treatment of coccidiosis and did not change biochemical parameters of blood. These findings suggest that silymarin might be used in chicken feeding in order to reduce the risk from lasalocid contamination of the broiler edible tissues. 相似文献
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Julia Radwan-Pragłowska Marek Piątkowski Diana Kitala Łukasz Janus Agnieszka Klama-Baryła Wojciech Łabuś 《国际聚合物材料杂志》2019,68(7):351-359
In this work we present a novel strategy for chitosan-based scaffolds. Chitosan is a versatile biopolymer obtained from waste biomass known of its favorable biological properties. Thus it can replace other polymers in the preparation of bioactive scaffolds. To increase its durability chitosan can be crosslinked into form of the hydrogel yet application of toxic crosslinkers may lead to loss of biocompability. Mesenchymal stem cells can be used in cell therapy for advanced wound treatment. However their culture requires special biomaterials application. In this article a novel microwave-assisted synthesis method for bioactive chitosan scaffolds is presented. 相似文献
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Bruzda Grzegorz Polkowski Wojciech Polkowska Adelajda Nowak Rafał Kudyba Artur Książek Marzanna Lech Sebastian Karczewski Krzysztof Giuranno Donatella 《Journal of Materials Science》2022,57(28):13724-13735
Journal of Materials Science - Boron-doped molybdenum silicides have been already recognized as attractive candidates for space and ground ultra-high-temperature applications far beyond limits of... 相似文献
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Monika Warat Ewelina Szliszka Ilona Korzonek-Szlacheta Wojciech Król Zenon P. Czuba 《International journal of molecular sciences》2014,15(7):11510-11522
Expression level of Tumor Necrosis Factor—related apoptosis—inducing ligand (TRAIL) receptors is one of the most important factors of TRAIL-mediated apoptosis in cancer cells. We here report for the first time data concerning TRAIL-R1 and TRAIL-R2 receptor expression on RAW264.7 macrophages. Three substances belonging to flavones: chrysin, apigenin and acacetin which differ from their substituents at the 4'' position in the phenyl ring were used in assays because of the variety of biological activities (e.g., anticancer activity) of the polyphenol compounds. The expression of TRAIL-R1 and TRAIL-R2 death receptors on non-stimulated and LPS (lipopolysaccharide)-stimulated macrophages was determined using flow cytometry. We demonstrate that RAW264.7 macrophages exhibit TRAIL-R1 surface expression and that the tested compounds: chrysin, apigenin and acacetin can inhibit TRAIL-R1 death receptor expression level on macrophages. 相似文献
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Tomasz Gancarz Katarzyna Berent Wojciech Skuza Katarzyna Janik 《Metallurgical and Materials Transactions A》2018,49(7):2684-2691
Magnesium has applications in the automotive and aerospace industries that can significantly contribute to greater fuel economy and environmental conservation. The Mg alloys used in the automotive industry could reduce mass by up to 70 pct, providing energy savings. However, alongside the advantages there are limitations and technological barriers to use Mg alloys. One of the advantages concerns phenomena occurring at the interface when joining materials investigated in this study, in regard to the effect of temperature and soldering time for pure Mg joints. Eutectic Zn-Al and Zn-Al alloys with 0.05 (wt pct) Li and 0.2 (wt pct) Na were used in the soldering process. The process was performed for 3, 5, and 8 minutes of contact, at temperatures of 425 °C, 450 °C, 475 °C, and 500 °C. Selected, solidified solder-substrate couples were cross-sectioned, and their interfacial microstructures were investigated by scanning electron microscopy. The experiment was designed to demonstrate the effect of time, temperature, and the addition of Li and Na on the kinetics of the dissolving Mg substrate. The addition of Li and Na to eutectic Zn-Al caused to improve mechanical properties. Higher temperatures led to reduced joint strength, which is caused by increased interfacial reaction. 相似文献