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11.
Matthias Schirmer Doris Perseke Eva Zena Daniel Schondelmaier Ivo Rudolph Bernd Loechel 《Microsystem Technologies》2007,13(3-4):335-338
A variety of different photo resists are used for fabrication of MEMS. Presently good results were reported for SU-8, a chemically
amplified negative tone photoresist. But SU-8 has a disadvantage for some applications in LIGA technique, especially in the
X-ray mask fabrication. After processing the finished resist pattern are hardly soluble from the substrate. This paper will
briefly describe the current status of the development of the new negative tone photoresist CAR 44 whose big advantage is
the easy removableness of the cross linked pattern.
This work widely uses the contents of the presentation “A New Removable Resist for High Aspect Ratio Applications” to the
High Aspect Ratio Micro Structure Technology workshop HARMST 2005 held in Gyeongyu (Republic of Korea), June 10–13, 2005. 相似文献
12.
A non-linear system with time averaging can be regarded as one composed of a time varying system with a variable parameter. A non-linear operation, such as squaring is performed on the signal of the system and followed by low pass filtering. This filtered signal controls, in turn, the variable parameter. This paper considers the steady state analysis of time averaged non-linear systems. The analysis covers both passive (with input) and oscillatory (no input) systems, In the passive case it is shown that the response is similar to that of a passive system with the poles shifted. The harmonic content and distortion are computed for both the oscillatory and passive case. An evaluation of the frequency is carried out for the oscillatory case. An interesting result is that the significant filter characteristic is the attenuation at twice the frequency. 相似文献
13.
C Sanz Y León J Troppmair UR Rapp I Varela-Nieto 《Canadian Metallurgical Quarterly》1999,18(2):429-437
Regulation of organogenesis involves a dynamic balance of the mechanisms regulating cell division, differentiation and death. Here we have investigated the pattern of expression of c-Raf kinase in the inner ear during early developmental stages and the consequences of manipulating c-Raf levels by misexpression of c-raf viral vectors in organotypic cultures of otic vesicle explants. We found that otic vesicles expressed c-Raf and its level remained constant during embryonic days 2 and 3 (E2-E3). c-Raf activity was increased in response to insulin like growth factor-I (IGF-I) and the activation by IGF-I of the c-Raf kinase pathway was a requirement to turn on cell proliferation in the otic vesicle. Overexpression of c-raf in E2.5 explants increased the proliferative response to low serum and IGF-I and blocked differentiation induced by retinoic acid. The increase in c-Raf levels also prevented nerve growth factor (NGF)-dependent induction of programmed cell death. Consistent with these results, the expression of a dominant negative c-Raf mutant potentiated retinoic acid action and decreased the rate of cell proliferation. We conclude that a strict control of c-Raf levels is essential for the co-ordination of the biological processes that operate simultaneously during early inner ear development. 相似文献
14.
15.
The development and future aspects of waste incineration in Germany are described with emphasis to corrosion problems. The heterogeneity of waste and special components are the cause of higher corrosion risk in comparison with other fuels, e.g. coal. The materials used in waste incineration plants are preferably the same as in fossil fuel fired boilers, namely un- and low-alloyed steels. Constructive measures are used to avoid enhanced corrosion. Examples are given for enhanced fire-side corrosion of evaporator and superheater tubes. Corrosion in the combustion chamber is to about 50% caused by local reducing conditions. At the other 50% chlorine compounds play a decisive role. Corrosion in the superheater area is usually caused by “high temperature chlorid corrosion”. 相似文献
16.
Molecular dynamics simulations were used to study the structure and dynamics of the Escherichia coli OmpF porin, which is composed of three identical 16-stranded beta-barrels. Simulations of the full trimer in the absence of water and the membrane led to significant contraction of the channel in the interior of each beta-barrel. With very weak harmonic constraints (0.005 kcal/mol A2/atom) applied to the main-chain C alpha atoms of the beta-barrel, the structure was stabilized without alteration of the average fluctuations. The resulting distribution of the fluctuations (small for beta-strands, large for loops and turns) is in good agreement with the x-ray B factors. Dynamic cross-correlation functions showed the importance of coupling between the loop motions and barrel flexibility. This was confirmed by the application of constraints corresponding to the observed temperature factors to the barrel C alpha atoms. With these constraints, the beta-barrel fluctuations were much smaller than the experimental values because of the intrinsic restrictions on the atomic motions, and the loop motions were reduced significantly. This result indicates that considerable care is required in introducing constraints to keep proteins close to the experimental structure during simulations, as has been done in several recent studies. Loop 3, which is thought to be important in gating the pore, undergoes a displacement that shifts it away from the x-ray structure. Analysis shows that this arises from the breakdown of a hydrogen bond network, which appears to result more from the absence of solvent that from the use of standard ionization states for the side chains of certain beta-barrel residues. 相似文献
17.
Moeck Christian Merk Markus Radny Dirk Auckenthaler Adrian Schirmer Mario Gabriel Thomas 《Grundwasser》2022,27(3):187-196
Grundwasser - Eine nachhaltige Wasserversorgung in urbanen Gebieten stellt aufgrund des Nutzungsdrucks sowie vielfältiger anthropogener Einträge eine große Herausforderung dar.... 相似文献
18.
Back Cover: Directed Divergent Evolution of a Thermostable D‐Tagatose Epimerase towards Improved Activity for Two Hexose Substrates (ChemBioChem 4/2015) 下载免费PDF全文
19.
Histamine is a pleiotropic mediator involved in a broad spectrum of (patho)-physiological processes, one of which is the regulation of inflammation. Compounds acting on three out of the four known histamine receptors are approved for clinical use. These approved compounds comprise histamine H1-receptor (H1R) antagonists, which are used to control allergic inflammation, antagonists at H2R, which therapeutically decrease gastric acid release, and an antagonist at H3R, which is indicated to treat narcolepsy. Ligands at H4R are still being tested pre-clinically and in clinical trials of inflammatory diseases, including rheumatoid arthritis, asthma, dermatitis, and psoriasis. These trials, however, documented only moderate beneficial effects of H4R ligands so far. Nevertheless, pre-clinically, H4R still is subject of ongoing research, analyzing various inflammatory, allergic, and autoimmune diseases. During inflammatory reactions in gut tissues, histamine concentrations rise in affected areas, indicating its possible biological effect. Indeed, in histamine-deficient mice experimentally induced inflammation of the gut is reduced in comparison to that in histamine-competent mice. However, antagonists at H1R, H2R, and H3R do not provide an effect on inflammation, supporting the idea that H4R is responsible for the histamine effects. In the present review, we discuss the involvement of histamine and H4R in inflammatory and inflammation-associated diseases of the gut. 相似文献
20.