Dynamic substrates

Keywords Biological interface Cell migration Cellular adhesion Dynamic substrates Immobilization Self-assembled monolayers... 

Carbon deposition occurs on the surface of a substrate inserted into the carbonization system using hydrocarbon gases, such as methane and propane [45], This process is a kind of chemical vapor deposition (CVD) and the products are called pyrolytic carbons. In order to control the structure, the deposition conditions have to be controlled. The deposition can occur on either static or dynamic substrates. In the former, the substrate is placed in a furnace, which is heated either by direct passing of electric currents or from the surroundings. In the latter, small substrate particles are fluidized... 

Professor Fiechter succeeded to show using the improved chemostat technique that glucose and oxygen influence various yeast stains differently. Beside the catabolite repression (glucose effect) a second regulation type exists which is controlled by the dynamic substrate flux (glucose). This causes different types... 

Our group has developed for the first time photoactivatable dynamic substrates based on the photocleavage reaction of 2-nitrobenzyl ester (Fig. 3.3.2) [2] and have been made various technical and conceptual innovations. The common feature is that the surface is initially noncell adhesive, but changes to cell adhesive in response to near-UV irradiation. On these substrates, we are able not only to pattern cells in arbitrary geometries, but also to induce their migration by the secondary irradiation. One of the biggest advantages... 

The most characteristic feature of the dynamic substrates is that they can be used to change the cellular pattern during cell cultivation. Two representative proof-of-concept experiments are shown in Fig. 3.3.5. By repeating the irradiation and cell seeding, we can... 

Yin PM, Nishina N, Kosakai Y, Yahiro K, Park Y, Okabe M (1997) Enhanced production of (L)-LA from com starch in a culture Rhizopus oryzae using an air-Uft bioreactor. J Ferment Bioeng 84 249-253. doi 10.1016/S0922-338X(97)82063-6 Zacharof MP, Lovitt RW (2013) Modelling and simulation of cell growth dynamics, substrate... 

For example, energy transfer in molecule-surface collisions is best studied in nom-eactive systems, such as the scattering and trapping of rare-gas atoms or simple molecules at metal surfaces. We follow a similar approach below, discussing the dynamics of the different elementary processes separately. The surface must also be simplified compared to technologically relevant systems. To develop a detailed understanding, we must know exactly what the surface looks like and of what it is composed. This requires the use of surface science tools (section B 1.19-26) to prepare very well-characterized, atomically clean and ordered substrates on which reactions can be studied under ultrahigh vacuum conditions. The most accurate and specific experiments also employ molecular beam teclmiques, discussed in section B2.3. 

The method of molecular dynamics (MD), described earlier in this book, is a powerful approach for simulating the dynamics and predicting the rates of chemical reactions. In the MD approach most commonly used, the potential of interaction is specified between atoms participating in the reaction, and the time evolution of their positions is obtained by solving Hamilton s equations for the classical motions of the nuclei. Because MD simulations of etching reactions must include a significant number of atoms from the substrate as well as the gaseous etchant species, the calculations become computationally intensive, and the time scale of the simulation is limited to the... 

Liidemann et al., 1997] Liidemann, S. K., Carugo, O., and Wade, R. C. Substrate access to cytochrome P450cam A comparison of a thermal motion pathway analysis with moleculM dynamics simulation data. J. Mol. Model. 3 (1997) 369-374... 

Example Yon can monitor improper torsion angles to determine wh ich side of a substrate m olecn le faces the active site of a protein. Select three atoms on the substrate molecule and a fourth in the active site. These atom s define an improper torsion angle. Save th is selection as a named selection. Then observe a plot of this improper torsion angle (in the Molecular Dynam ics Results dialog... 

The LC/TOF instmment was designed specifically for use with the effluent flowing from LC columns, but it can be used also with static solutions. The initial problem with either of these inlets revolves around how to remove the solvent without affecting the substrate (solute) dissolved in it. Without this step, upon ionization, the large excess of ionized solvent molecules would make it difficult if not impossible to observe ions due only to the substrate. Combined inlet/ionization systems are ideal for this purpose. For example, dynamic fast-atom bombardment (FAB), plas-maspray, thermospray, atmospheric-pressure chemical ionization (APCI), and electrospray (ES)... 

The MYD analysis assumes that the atoms do not move as a result of the interaetion potential. The eonsequenees of this assumption have recently been examined by Quesnel and coworkers [50-55], who used molecular dynamic modeling techniques to simulate the adhesion and release of 2-dimensional particles from 2-D substrates. Specifically, both the Quesnel and MYD models assume that the atoms in the different materials interact via a Lennard-Jones potential

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