Sequence flexibility

Limitations of the TR-FRET approach in terms of peptide sequence flexibility must be considered as well. The prerequisites and limitations for successful peptide labeling, for example, for the LANCE Ultra approach include (1) need for a cysteine in position zero, i.e., the peptide s N terminus, (2) no other free cysteine allowed in the peptide sequence, (3) overall charge different from zero, (4) no disulfide bonds in the peptide, (5) no tryptophan or histidine at the C terminal position, and (6) maximum length of 30 amino acids (personal communication). 

Returnable containers also play a role in regulating the flow of parts. We know how many returnable containers are in circulation, and this number places a cap on how much material is in the supply chain. The two-bin system and variations on it are examples of the use of returnable containers as pull signals. For most items, however, kanbans are preferred because they offer more sequencing flexibility. 

This test consists of two parts. Part A consists of 15 numbered circles distributed over a white sheet of paper. The child is required to connect the circles with a pencil line as quickly as possible, beginning with circle 1 and proceeding in numerical sequence. Part B consists of 15 circles numbered from 1 to 8 and lettered from A to G. The child is required to connect the circles, alternating between sequences of numbers and letters. Two scores are recorded - the number of seconds required to finish each part and the number of errors. This test appears to require immediate recognition of the symbolic significance of numbers and letters, ability to scan the page continuously to identify the next number or letter in sequence, flexibility in integrating the numerical and alphabetical sequence, and completion of these requirements under the pressure of time. 

Toluene Diisocyanate. Toluene diisocyanate is the basic raw material for production of flexible polyurethane foams. It is produced by the reaction sequence shown below, in which toluene is dinitrated, the dinitrotoluene is hydrogenated to yield 2,4-diaminotoluene, and this diamine in turn is treated with phosgene to yield toluene 2,4-diisocyanate. 

Flexible batch. Both the formula and the processing instructions can change from batch to batch. Emulsion polymerization reactors are a good example of a flexible batch facility. The recipe for each produc t must detail Both the raw materials required and how conditions within the reac tor must be sequenced in order to make the desired product. 

In some cases, whole parts of the protein are missing from the experimentally determined structure. At times, these omissions reflect flexible parts of the molecule that do not have a well-defined structure (such as loops). At other times, they reflect parts of the molecule (e.g., terminal sequences) that were intentionally removed to facilitate the crystallization process. In both cases, structural models may be used to fill in the gaps. 

Modal balancing is based on the fact that a flexible rotor may be balanced by eliminating the effect of the unbalance distribution in a mode-by-mode sequence. Typical principal modes of a symmetric, uniform shaft are shown... 

Figure 9.12 Schematic diagram of the structure of the heterodimeric yeast transcription factor Mat a2-Mat al bound to DNA. Both Mat o2 and Mat al are homeodomains containing the helix-turn-helix motif. The first helix in this motif is colored blue and the second, the recognition helix, is red. (a) The assumed structure of the Mat al homeodomain in the absence of DNA, based on Its sequence similarity to other homeodomains of known structure, (b) The structure of the Mat o2 homeodomain. The C-terminal tail (dotted) is flexible in the monomer and has no defined structure, (c) The structure of the Mat a 1-Mat a2-DNA complex. The C-terminal domain of Mat a2 (yellow) folds into an a helix (4) in the complex and interacts with the first two helices of Mat a2, to form a heterodimer that binds to DNA. (Adapted from B.J. Andrews and M.S. Donoviel, Science 270 251-253, 1995.)...

As a class the aliphatic polyalkenamers have low values due to a combination of low chain stiffness and low interchain attraction. The presence of double bonds has the effect of increasing the flexibility of adjacent single bonds (see Chapter 4) and overall this leads to a reduction in. Thus in the sequence from polydecenamer down to polypentenamer an increase in the double bond concentration leads to a lowering of Tg. On the other hand the Tg of polybutenamer, i.e. poly butadiene, is somewhat higher than that of polypentenamer, presumably because the proportion of stiff links, i.e. double bonds, becomes sufficiently high to override the flexibilising effect on adjacent chains. Consequently the polypentenamers have the lowest Tg values known for hydrocarbon polymers (cis- -114°C, trans- -97°C). 

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