Sequence constraints

Fig. 4.4 Double duplex invasion of pseudo complementary PNAs. In order to obtain efficient binding, the target (and thus the PNAs) should contain at least 50% AT (no other sequence constraints), and in the PNA oligomers all A/T base pairs are substituted with...

Sequencing Constraints Associated with Production Scheduling... 

Sequencing Constraints for Recycle/Reuse in the Absence of Reusable Water Storage... 

Sequencing Constraints that Associate Production Scheduling and Water Recycle/Reuse... 

In the presence of wastewater minimization, the sequence constraints initially presented in Chapter 2 are modified as follows. The following constraints stipulates that the task corresponding to state s n. can only commence once all the previous tasks and their corresponding washing operations are complete. 

Occasionally it is useful to write a sequencing constraint in text form, although it could usually be described using the preferred state chart technique from the preceding section. 

A sequence constraint may govern actions, stating the possible sequences it may be expressed in the form of a state chart. Of all possible sequences of finer actions, only some may constitute an occurrence of the abstract action for example, the card reader and ATM keys can always be used, but only some sequences constitute a withdraw action. An action refinement sequence relates finer sequences to specific abstract actions, and can be expressed in the form of a state chart. 

Montaudo, M.S. Sequence Constraints in a Glycine-Lactic Acid Copolymer Determined by MALDI-MS. Rapid Commun. Mass Spectrom. 1999, 13, 639-644. 

Functional RNA molecules, whether natural or produced in the lab through directed evolution, typically require distinctive secondary structures to fulfill their function for a nice example we refer to Schwienhorst [8]. These structures serve as a scaffold that allows the formation of, e. g., a catalytic site. Thus, sequence constraints observed in RNA molecules selected for a particular function, such as binding or catalysis, may be due to direct involvement in that function or due to stabilization of the structure. Predicted RNA secondary structures can be most helpful to identify such structural constraints and to interpret the results of a directed evolution experiment in terms of structure-function relationships. 

The sequence constraints state, for instance, that if yi — 0, then y2 = 0 (i.e., column 2 does not exist if column 1 does not exist). The utility limits constraints state that not more than one hot utility is allowed to be used at each reboiler. 

Fig. 3.12. Ribbon structure (A) and L2 loop (B) of EcCM. Random mutagenesis of the L2 loop followed by selection for chorismate mu-tase activity in vivo showed little sequence constraint on solvent exposed turn residues, aside from a modest bias in favor of hydrophilic amino acids [85]. In contrast, long-range tertiary contacts impose a strict requirement for hydrophobic aliphatic amino acids at position 68.

Montaudo, M.S., Sequence Constraints in Glycine-Lactic acid Copolymer Determined by MALDl-MS analysis, Rapid Comm Mass Spectrom, 13, 639 (1999). 

Since the original work of Merrifidd, the field of solid phase peptide synthesis has evolved enormously to sophisticated automated equipment. Today s modern instrument has been engineered to a level at which a researcher only has to input a sequence into a computer and allow the machine to produce the desired target peptide. Contrary to the belief of researchers who have just entered the field of solid phase peptide synthesis and claim that the field is a mature science, there is unfortunately no guarantee that an individual instrument will prepare a desired sequence effectively, due to chemical and sequence constraints. Although synthesizers have removed the tediousness of repetitive synthetic operations, chemists still must decide the appropriate chemical pathway, select an instrument that will satisfy their demands, and interpret the data generated. 

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