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91.
The main objective of this study was to identify critical factors that measure management efforts with regard to quality, safety, and ergonomics issues for their simultaneous improvement. Eleven identified management activity areas have been synthesized from the literature as the most important areas that meet all stakeholders' needs. Factors were then developed to measure the efficiency of these activities through a questionnaire. The overall response rate of the survey questionnaire was 47%. The reliability coefficients ranging from 0.73 to 0.85 indicated that some scales or management activity areas are more reliable in measuring potential for improvements in terms of quality, ergonomics, safety, and efficiency. The proposed instrument for quantifying management efforts with respect to simultaneous improvements in the areas of quality, ergonomics, and safety was found to be valid and reliable. © 2005 Wiley Periodicals, Inc. Hum Factors Man 15: 213–232, 2005. 相似文献
92.
Hydrolysis of Phosphatidylcholine-Isoprostanes (PtdCho-IP) by Peripheral Human Group IIA,V and X Secretory Phospholipases A<Subscript>2</Subscript> (sPLA<Subscript>2</Subscript>) 下载免费PDF全文
Biologically active F- and E/D-type-prostane ring isomers (F2-IP and E2/D2-IP, respectively) are produced in situ by non-enzymatic peroxidation of arachidonic acid esterified to GroPCho (PtdCho-IP) and are universally distributed in tissue lipoproteins and cell membranes. Previous work has shown that platelet-activating factor acetylhydrolases (PAF-AH) are the main endogenous PLA2 involved in degradation of PtdCho-IP. The present study shows that the PtdCho-IP are also subject to hydrolysis by group IIA, V and X secretory PLA2, which also have a wide peripheral tissue distribution. For this demonstration, we compared the LC/MS profiles of PtdCho-IP of auto-oxidized plasma lipoproteins after incubation for 1–4 h (37 °C) in the absence or presence of recombinant human sPLA2 (1–2.5 µg/ml). In the absence of exogenously added sPLA2 the total PtdCho-IP level after 4 h incubation reached 15.9, 21.6 and 8.7 nmol/mg protein of LDL, HDL and HDL3, respectively. In the presence of group V or group X sPLA2 (2.5 µg/ml), the PtdCho-IP was completely hydrolyzed in 1 h, while in the presence of group IIA sPLA2 (2.5 µg/ml) the hydrolysis was less than 25% in 4 h, although it was complete after 8–24 h incubation. This report provides the first demonstration that PtdCho-IP are readily hydrolyzed by group IIA, V and X sPLA2. A co-location of sPLA2 and the substrates in various tissues has been recorded. Thus, the initiation of interaction and production of isoprostanes in situ are highly probable. 相似文献
93.
Proper conditioning of an oil sand/water slurry is essential for the efficient extraction of bitumen. The conditioning process depends on such variables as ore grade, temperature, mixing intensity, mixing time, and water composition. A technique has been developed in which a microscope and video cameras are used to observe a slurry stirred in a glass cell to evaluate, on a comparative basis, the effect of conditioning parameters on bitumen recovery. Several ores and their blends were studied and found to exhibit large differences in their conditioning behaviour. The method offers the capability of diagnosing ore processability problems and optimizing slurry conditioning. 相似文献
94.
Zirconia polycrystals stabilised with 7 mol.% CaO containing 10 vol.% WC particles (Ca-PSZ/WC) were obtained by using zirconia nanopowder and WC micropowder. Cold isostatically pressed samples were pressureless sintered in argon at 1350–1950 °C. The influence of the sintering temperature and the incorporation of WC particles on the phase composition and mechanical properties of the composites were studied. Decomposition of WC due to the reaction with the zirconia matrix was found. W2C and metallic tungsten were detected as decomposition products when heat treated below 1750 °C. At higher temperatures, ZrC is formed. The mechanism of WC decomposition was discussed. The zirconia polycrystals modified with in situ formed W and W2C inclusions showed a bending strength of 417 ± 67 MPa, a fracture toughness of 5.2 ± 0.3 MPa m0.5 and a hardness of 14.6 ± 0.3 GPa. 相似文献
95.
Conditioning of an oil sand slurry is a critical step in the extraction of bitumen from oil sand ore. To model the conditioning process, a constant‐number Monte Carlo algorithm is used to simulate the mean‐field kinetics of coalescing bitumen drops and air bubbles. The coalescence rate of drops and bubbles is described by the model of Coulaloglou and Tavlarides (1977). Simulations yield results that are consistent with aerated bitumen drop sizes and conditioning times reported in the literature. The effects of turbulent energy, bitumen concentration, and initial bitumen drop size on the evolution of drop size distributions are investigated. 相似文献
96.
C. L. Peterson D. L. Auld R. A. Korus 《Journal of the American Oil Chemists' Society》1983,60(8):1579-1587
Although vegetable oil cannot yet be recommended as a fuel for general use, considerable progress in recovery and use of rapeseed
oil (Brassica napus L.) for diesel operation has been made. Operation of a small-scale screwpress plant (40 kg/hr) was demonstrated. Maintenance
of screw and end rings was a major problem. The plant has operated with a recovery efficiency of 77% and has processed 10,100
kg of seed in 230 hr. High viscosity of the rapeseed oil and its tendency to polymerize within the cylinder were major chemical
and physical problems encountered. Attempts to reduce the viscosity of the vegetable oil by preheating the fuel were not successful
in sufficiently increasing the temperature of the fuel at the injector to be of value. Short-term engine performance with
vegetable oils as a fuel in any proportion show power output and fuel consumption to be equivalent to the diesel-fueled engines.
Severe engine damage occurred in a very short time period in tests of maximum power with varying engine rpm. Additional torque
tests with all blends need to be conducted. A blend of 70/30 winter rape and No. 1 diesel has been used successfully to power
a small single-cylinder diesel engine for 850 hr. No adverse wear, effect on lubricating oil or effect on power output were
noted.
Approved as Paper No. 8237 of the Idaho Agricultural Experiment Station. 相似文献
97.
Wioleta Kowalska Micha Zarobkiewicz Waldemar Tomczak Justyna Wo Izabela Morawska Agnieszka Bojarska-Junak 《International journal of molecular sciences》2022,23(6)
Monocytes are one of the least studied immune cells with a potentially important role in the pathogenesis of chronic lymphocytic leukemia (CLL). Nevertheless, data regarding the role of subpopulations of monocytes in the CLL microenvironment are still limited. For the very first time, this study presents an assessment of monocyte subsets divided according to SLAN and CD16 expression in CLL patients. The study involved 70 freshly diagnosed CLL patients and 35 healthy donors. Using flow cytometry, monocyte subpopulations were assessed among PBMCs. CD14+ monocytes can be divided into: “classical” (CD14+CD16−SLAN−), “intermediate” (CD14+CD16+SLAN−) and “non-classical” (CD14dimCD16+SLAN+). In our study, we noted an increased percentage of non-classical monocytes with intracellular expression of TNF and IL-12. On the other hand, among the intermediate monocytes, a significantly higher percentage of cells synthesizing anti-inflammatory IL-10 was detected. The percentage of CD14dimCD16+SLAN+ monocytes producing TNF and IL-12 decreased with the stage of CLL and inversely correlated with the expression of the prognostic factors ZAP-70 and CD38. Moreover, the percentage of CD14dimCD16+SLAN+ monocytes producing TNF and IL-12 was lower in CLL patients requiring treatment. This may indicate the beneficial effect of non-classical monocytes on the anti-tumor response. 相似文献
98.
Jan Rudolph Naceur Gaaloul Yeshpal Singh Holger Ahlers Waldemar Herr Torben A. Schulze Stephan Tobias Seidel Christina Rode Vladimir Schkolnik Wolfgang Ertmer Ernst Maria Rasel Hauke Müntinga Thorben Könemann Andreas Resch Sven Herrmann Claus Lämmerzahl Tim van Zoest Hansjörg Dittus Anika Vogel André Wenzlawski Klaus Sengstock Nadine Meyer Kai Bongs Markus Krutzik Wojciech Lewoczko-Adamczyk Max Schiemangk Achim Peters Michael Eckart Endre Kajari Stefan Arnold Gerrit Nandi Wolfgang P. Schleich Reinhold Walser Tilo Steinmetz Theodor W. Hänsch Jakob Reichel 《Microgravity science and technology》2011,23(3):287-292
Clouds of ultra-cold atoms and especially Bose–Einstein condensates (BEC) provide a source for coherent matter-waves in numerous earth bound experiments. Analogous to optical interferometry, matter-wave interferometers can be used for precision measurements allowing for a sensitivity orders of magnitude above their optical counterparts. However, in some respects the presence of gravitational forces in the lab limits experimental possibilities. In this article, we report about a compact and robust experiment generating Bose–Einstein condensates in the drop tower facility in Bremen, Germany. We also present the progress of building the succeeding experiment in which a two species atom interferometer will be implemented to test the weak equivalence principle with quantum matter. 相似文献
99.
100.