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A laser pumped zig-zag dye laser operating at 568 nm with a pulse length ~2 μs has been sealed to high power using a MOPA configuration. Pulse energies in excess of 7 J with beam quality <2 XDL have been achieved under repetitively pulsed, 10 Hz operation. RMS jitter was measured as 0.12 of a 1 XDL spot. The device has operated with over 70 W output for runs up to 5 s. Substantially longer run times and output powers are possible. This device represents an advance in dye laser capabilities. Improvement in pointing accuracy of better than an order of magnitude have been demonstrated. In addition, an improvement in beam quality by about an order of magnitude has been achieved compared to other dye lasers operating in this power range 相似文献
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Malgorzata Kloc Ahmed Uosef Jacek Z. Kubiak Rafik Mark Ghobrial 《International journal of molecular sciences》2021,22(1)
The development, progression, or stabilization of the atherosclerotic plaque depends on the pro-inflammatory and anti-inflammatory macrophages. The influx of the macrophages and the regulation of macrophage phenotype, inflammatory or anti-inflammatory, are controlled by the small GTPase RhoA and its downstream effectors. Therefore, macrophages and the components of the RhoA pathway are attractive targets for anti-atherosclerotic therapies, which would inhibit macrophage influx and inflammatory phenotype, maintain an anti-inflammatory environment, and promote tissue remodeling and repair. Here, we discuss the recent findings on the role of macrophages and RhoA pathway in the atherosclerotic plaque formation and resolution and the novel therapeutic approaches. 相似文献
5.
Fia?kowska E Kocerba W Pajdak-Stós A Klimek B Fyda J 《Water science and technology》2011,64(2):403-408
The novel idea of using rotifers Lecane inermis (Rotifera, Monogononta) as a tool to overcome activated sludge bulking generates an on-going need to study rotifer biology. The results of biological research on rotifers can serve to improve the method so that it can be most effective when applied in treatment plants. The aim of this study was to test the effect of temperature on four selected rotifer clones originating from different treatment plants. The rate of population development from a single individual (parthenogenetic female) during a 10-day experiment was measured at three temperatures: 8, 15 and 20 degrees C. The temperatures used reflect the annual temperature distribution in the majority of municipal wastewater treatment plants in the temperate zone. The growth rate coefficient (r) and doubling time (tD) were calculated for each clone. Under the most favourable conditions (20 degrees C), rvalues varied between 0.41 and 0.47 d and doubling time between 1.5 and 1.7 d. At a temperature of 15 degrees C, the doubling time was approximately two times longer (2.5-3.4 d). The strongest intraspecific variations were observed at the lowest temperature of 8 degrees C. At this temperature, one of the clones almost failed to proliferate, and another exhibited a doubling time of 7.9 d. The doubling times were a few times greater for the remaining two clones (60 d for Lk1, 33.3 d for Lk4). These results could be very useful in predicting the chances that the rotifers would survive in a biological reactor in a wastewater treatment plant at the temperatures used in these reactors. 相似文献
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Malgorzata Plaza 《Information Systems Frontiers》2008,10(3):347-359
Although the Earned Value Method (EVM), a multi-dimensional project control system, has been widely used since 1960, there
has been little research focused specifically on its application in IS implementation. The management of IS projects—including
the accurate forecasting of project duration—is complicated by the strong impact of the learning curve on the effectiveness
of EVM. This study makes new contributions by advancing formulas for the accurate prediction of project duration, and by developing
a decision support model in which the learning curve is fully integrated with EVM, and performance changes due to learning
are isolated from other factors affecting project duration. The study makes three contributions to the understanding and use
of EVM in IS implementation: (1) It provides an extended version of EVM, (2) it provides an illustration of the application
of EVM to a real project situation based on empirical data from an ERP implementation project, and (3) it provides a theoretical
basis for empirical studies of IS project control techniques. The decision support model can be used to determine both the
learning curve coefficient and the project completion date during the early stages of a project, and it thus offers a significant
practical contribution to the management of IS projects.
Dr. Margaret Plaza is an Associate Professor of Information Technology Management at Ryerson University and a Senior Research Scientist in IITM. She holds an M.Sc. in Mechanical Engineering and a Ph.D. in Production Engineering from Politechnika Krakowska (Cracow University of Technology) where she specialized in flexible manufacturing systems. Dr. Plaza is also a PEng. (Ontario), PMP, and CIA and has over 20 years’ industry experience working with consulting and manufacturing firms in both private and public sectors. She managed or provided consulting for ERP and supply chain implementations. Her current research focuses on organizational learning, technology management and the supply chain. She has developed decision models and decision support technologies to assist managers with problems in new technology implementations. 相似文献
Malgorzata PlazaEmail: |
Dr. Margaret Plaza is an Associate Professor of Information Technology Management at Ryerson University and a Senior Research Scientist in IITM. She holds an M.Sc. in Mechanical Engineering and a Ph.D. in Production Engineering from Politechnika Krakowska (Cracow University of Technology) where she specialized in flexible manufacturing systems. Dr. Plaza is also a PEng. (Ontario), PMP, and CIA and has over 20 years’ industry experience working with consulting and manufacturing firms in both private and public sectors. She managed or provided consulting for ERP and supply chain implementations. Her current research focuses on organizational learning, technology management and the supply chain. She has developed decision models and decision support technologies to assist managers with problems in new technology implementations. 相似文献
7.
Viscosity is one of the most important attributes of rye-based products related to some health benefits. To identify the factors affecting arabinoxylan-dependent extract viscosity (AX-EV) of rye bread, the structural features of water-extractable arabinoxylans (WE-AXs) and their ammonium sulphate precipitated subfractions were investigated in breads with varied viscosities. Also, an endoxylanase activity in the starting flours was examined. The HPSEC-RI profiles revealed the higher extent of AX depolymerisation in whole-meal bread (WMB) when compared to that in endosperm bread (EB), resulting in its lower AX-EV. This was mostly related to lower molecular weight of the parent WE-AX fraction with distinctly lower proportion of 2-Xylp in the chain. The AX-EV of rye bread decreased with decreasing proportion of AX-I, the major subfraction with 3-Xylp as only branching site. The endoxylanase activity was at least two times lower in endosperm flour than that in WM and negatively correlated with the AX-EV of WMB. The importance of densely substituted AX subfractions with exclusively 2-Xylp and 2,3-Xylp branches, protecting the AX-I from enzymic degradation during bread-making, has been evidenced. 相似文献
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Synthesis of trimethylene carbonate/ϵ‐caprolactone copolymers initiated with zinc alkoxide: influence of copolymer chain microstructure on thermal and mechanical properties
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Malgorzata Pastusiak Piotr Dobrzynski Janusz Kasperczyk Michal Sobota Bozena Kaczmarczyk Henryk Janeczek 《Polymer International》2017,66(9):1259-1268
Ethylzinc(II ) ethoxide is a highly active and efficient initiator for the bulk polymerization of 1,3‐trimethylene carbonate and its copolymerization with ? ‐caprolactone. This initiator allows one to obtain (co)polymers with high molar masses in quite a short time. Significant difference in co‐monomer reactivity and relatively low participation of intermolecular transesterification processes lead to the obtained copolymers being characterized by a gradient chain microstructure. In 13C NMR spectra, in all regions, we observed the presence of triads which were distinctly represented by four peaks for the carbonyl signal. Mechanical tests showed that copolymers containing 70% and more of ? ‐caprolactone presented a relatively high Young's modulus and a very high maximum elongation factor; therefore these materials are promising in many biomedical applications. Due to the high reaction rate, we also made an attempt at copolymerization using reactive extrusion which gave promising results. © 2017 Society of Chemical Industry 相似文献
10.
Malgorzata Młynarczyk Malgorzata Sznitowska Dorota Watrobska-Swietlikowska 《Drug development and industrial pharmacy》2013,39(4):355-362
Antimicrobial efficacy of methyl and propylparaben combination as potential preservatives for submicron emulsions, and the effect of oil and lecithin concentration on the microbial growth were investigated. Parabens were ineffective in standard or doubled concentrations as per pharmacopoeial criteria. Poor growth inhibition and multiplication of reference strains point to protective and growth properties of submicron emulsions. No correlation was observed between oil/lecithin ratio and efficacy of parabens; partitioning of the latter into the oily phase and lipophilic domains could be the reason for such effect. Further studies are necessary to establish a stable and safe composition of such formulations. 相似文献