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排序方式: 共有227条查询结果,搜索用时 15 毫秒
91.
U Keil LE Chambless A D?ring B Filipiak J Stieber 《Canadian Metallurgical Quarterly》1998,116(4):19-20
Hypotensive efficacy and tolerance of a new antiglaucoma drug lathanoprost, a 0.005% xalathane solution, prostaglandin F2 alpha analog, is studied. A single instillation of xalathane decreased ophthalmic tone in normal subjects and glaucoma patients with increased intraocular pressure. Combination of the drug with other hypotensive agents (pilocarpine + timolol) amplified their hypotensive effects. Long (3 months) follow-up showed that xalathane efficacy is comparable to that of pilocarpine and timolol combination but it is tolerated much better. 相似文献
92.
We investigate the problem of how nonnatural entities are represented by examining university students' concepts of God, both professed theological beliefs and concepts used in comprehension of narratives. In three story processing tasks, subjects often used an anthropomorphic God concept that is inconsistent with stated theological beliefs; and drastically distorted the narratives without any awareness of doing so. By heightening subjects' awareness of their theological beliefs, we were able to manipulate the degree of anthropomorphization. This tendency to anthropomorphize may be generalizable to other agents. God (and possibly other agents) is unintentionally anthropomorphized in some contexts, perhaps as a means of representing poorly understood nonnatural entities. 相似文献
93.
Reduction of the optical loss and optimization of polycyanurate thermosets used in integrated optics
C. Dreyer M. Bauer J. Bauer N. Keil H. Yao C. Zawadzki 《Microsystem Technologies》2002,7(5-6):229-238
The current infrastructure of the communication has to be expanded rapidly due to the dramatic increase of data, that is
transferred via the internet. The optical network technology is the most suitable technology for this demand. Not only glass
fibres are required, but also a broad range of optical components like splitters, switches and multiplexers, which are usually
produced in silica technology. Polymeric materials are becoming more and more interesting for these applications, since they
e.g. promise lower power consumption and lower production costs than their silica based pendants. Polycyanurate ester resins
are a relatively new class of high-performance polymers with outstanding properties, for example high thermal stability, low
optical loss, low dielectric constant, good adhesion and amazing mechanical properties. This paper focuses on the optical
loss of such materials at 1550 nm, in the optimisation for use in integrated optics and for the production of embedded waveguides.
Received: 31 May 2001 / Accepted: 16 July 2001 相似文献
94.
E Baranowski G Keil J Lyaku FA Rijsewijk JT van Oirschot PP Pastoret E Thiry 《Canadian Metallurgical Quarterly》1996,53(1-2):91-101
Topoisomerases are enzymes that catalyse the transient breakage and rejoining of either one (topo I) or two (topo II) DNA strands, to allow one strand to pass through another and prevent unresolvable tangles during processes such as DNA replication. A number of important clinical antitumour agents act through inhibition of topo II enzymes, while some topo I inhibitors appear likely to enter clinical use. Although these chemicals do not covalently interact with DNA, they have strong mutagenic potential, generally causing events at the level of the chromosome rather than that of the gene. Most are recombinogens, may affect gene expression and can also lead to aneuploidy through effects on chromosome segregation. Most topo I and topo II inhibitors primarily cause mutagenic events associated with the replication fork. However, at least in mitotic chromosomes, topo II enzymes are located at the base of chromosome loops, and topo II inhibitors may facilitate subunit exchanges, leading to major deletions and illegitimate recombinational events. There is evidence that programmed cell death provides an alternative pathway to mutagenesis following treatment by either topo I or topo II inhibitors. The final fate of the cell will result from a balance between these two processes. 相似文献
95.
Assigned 64 clients from 3 manpower agencies to 1 of 3 treatment conditions: (a) a combined-treatment program of videotape-feedback and behavior-modification techniques (n = 24), (b) a videotape-feedback-only program (n = 21), and (c) a no-treatment (control) program (n = 19). The Culture Fair Intelligence Test was administered to all Ss prior to the program. Results show that on 9 out of 10 measures of observable interview behavior, personnel interviewers, acting as judges in randomly presented videotaped interviews, reported greater positive change from the initial to the final interview among the combined-treatment group. Moreover, on 2 of these items, analysis of variance showed that the change was statistically significant, and on an overall evaluation item concerning the probability of hire, positive change also reached statistical significance. On the probability of hire item, both the video and combined groups' IQ test scores were significantly related to positive change. Results suggest that the application of these techniques could substantially increase the chances of a disadvantaged person's obtaining suitable employment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
96.
97.
Henrik Wimelius Lars Mathiassen Jonny Holmstrm Mark Keil 《Information Systems Journal》2021,31(1):198-225
To realize their strategic goals and maintain a competitive advantage in the digital era, organizations must periodically renew their digital platforms and infrastructures. However, knowledge about such technology renewal is scattered across diverse research streams, so insights into the process are both limited and fragmented. In this article, we consolidate insights from previous research to conceptualize technology renewal as an inherently paradoxical digital transformation process that requires organizations to simultaneously remove their technological foundation and build on the practices that depend on it to implement a new technological foundation. Previous research suggests that technology renewal initiatives are driven by three paradoxical tensions: (a) established vs renewed technology usage, (b) deliberate vs emergent renewal practices and (c) inner vs outer renewal contexts. We apply this framing to a longitudinal case study in which we analyse and explain how an organization's responses to manifestations of these tensions eventually led to a vicious cycle of continued investments into two overlapping and largely incompatible digital platforms over a 9‐year period. Based on these conceptual and empirical insights, we theorize technology renewal as a paradoxical, and increasingly critical, digital transformation process that forces managers to make decisions in complex and ambiguous choice situations. 相似文献
98.
Dr. Claudia Keil Julia Klein Dr. Franz-Josef Schmitt Dr. Yunus Zorlu Prof. Dr. Hajo Haase Dr. Gündoğ Yücesan 《Chembiochem : a European journal of chemical biology》2021,22(11):1925-1931
We report the application of a highly versatile and engineerable novel sensor platform to monitor biologically significant and toxic metal ions in live human Caco-2 enterocytes. The extended conjugation between the fluorescent porphyrin core and metal ions through aromatic phenylphosphonic acid tethers generates a unique turn off and turn on fluorescence and, in addition, shifts in absorption and emission spectra for zinc, cobalt, cadmium and mercury. The reported fluorescent probes p-H8TPPA and m-H8TPPA can monitor a wide range of metal ion concentrations via fluorescence titration and also via fluorescence decay curves. Cu- and Zn-induced turn off fluorescence can be differentially reversed by the addition of common chelators. Both p-H8TPPA and m-H8TPPA readily pass the mammalian cellular membrane due to their amphipathic character as confirmed by confocal microscopic imaging of living enterocytes. 相似文献
99.
Joanna Stachowicz Anette Lanter Lorenz Gygax Edna Hillmann Beat Wechsler Nina Maria Keil 《Journal of dairy science》2019,102(2):1508-1521
Access to an outdoor run might provide some benefits for the social and activity behavior of dairy goats. The aim of this study was to investigate the influence of weather parameters on outdoor run use by dairy goats under temperate weather conditions. Data were collected from February to April and in October, 2014, on 14 commercial dairy goat farms in Switzerland and Germany for 14 d per farm. Temperature, humidity, solar radiation, wind speed, and rain amount were measured continuously using a weather station. The outcome variables, average proportion of the herd in the outdoor run (proportion of herd in run) and average frequency of goats entering the outdoor run per hour in relation to group size (frequency of entries to run), were assessed by video data. Temperature, humidity, and solar radiation were combined to create the parameter “warmth” by means of a principal component analysis, whereas wind speed and rain (rain events and rain amount) were used in their original form as explanatory variables. Additionally, the effect of the comprehensive climate index on outdoor run use was investigated. Data were analyzed using linear mixed effects models. Increasing “warmth” increased, whereas increasing wind speed reduced, the proportion of herd in run. With increasing comprehensive climate index, the proportion of herd in run and the frequency of entries to run increased. On days without rain, the proportion of herd in run and the frequency of entries to run were markedly higher than during comparable daytime hours with rain. In the hour before the rain started and after it had stopped, more goats were in the outdoor run than during rain hours, but still fewer than during comparable daytime hours on days without rain. Furthermore, the proportion of herd in run and the frequency of entries to run decreased to a very low level when the rain amount exceeded 1 mm/h. To conclude, in the measured ranges of temperature (?0.8 to +16.5°C), humidity (34.8 to 99.2%), solar radiation (25.9 to 519.8 W/m2), and wind speed (0 to 4 m/s), warmer conditions increased the outdoor run use, whereas the goats clearly avoided light wind and rain. Therefore, in the outdoor runs, protection against rain and wind could promote their use under temperate weather conditions. Furthermore, ensuring optimized access to solar radiation by considering the exposure of the outdoor run might be of advantage, as direct sun exposure induces warmer conditions. 相似文献
100.
Managing information systems (IS) projects requires what we refer to as ‘control ambidexterity’, which is the use of different types of control to meet conflicting demands. This leads to the use of contrasting styles of IS project management and creates tensions in managerial practice, neither of which are well understood. We address this theoretical gap in our understanding based on an exploratory case study of an IS implementation project in the financial services industry. Adopting the lens of management styles as a meta-theoretical perspective, we sought to address two research questions: (1) Which management style(s) do IS project managers draw upon in practice and why? (2) What kinds of tensions result for IS project managers and team members from drawing upon contrasting management styles in combination – and how do IS project managers and team members deal with these tensions? Two contrasting styles of management emerged from our data – bureaucratic and collaborative – that are drawn upon by IS project managers to achieve control ambidexterity. Furthermore, drawing upon these two different styles in combination within the confines of a single project creates tensions. We explore these tensions and present an illustrative example of how IS project managers can deal with these tensions successfully in practice. Specifically, we find that they can be dealt with effectively by a tandem of two project managers who share responsibility for managing the IS project. The findings of this study have important implications for our understanding of control ambidexterity in IS projects. 相似文献