Conservation active

Figure 13.3 Thermally activated conservative motion of a small-angle symmetric tilt...

Lee, S. and Gogate, M. R., A single-stage, liquid-phase DME synthesis from syngas III. Dual catalyst crystal growth, deactiviation, and activity conservation studies, Fuel Sci. Technol. Internal, 9(8) 949—976 (1991). 

A conservation laboratory equipped to deal with finds had functioned at the Trust headquarters at Portsmouth since 1979, and the external Advisory Committees met regularly to review progress and monitor the work as it progressed. In 1982 a suitable dock in the Royal Naval Base was equipped to receive the hull while it was cleaned, restored and conserved. The salvage plans and a detailed research programme to define passive and active conservation techniques went on concurrently with the excavation offshore between 1980 and 1982. 

With the active conservation of waterlogged archaeological wood, the major problem is not that we do not have adequate treatment methods available, it is in recognising the serious limitations of these methods. However, those methods involving PEG offer the greatest flexibility and variability. 

Kobasa D, Rodgers ME, Wells K, Kawaoka Y (1997) Neuraminidase hemadsorption activity, conserved in avian influenza A virases, does not influence viral replication in ducks. J Virol... 

Lee D and Albrecht A C 1993 On global energy conservation in nonlinear light matter interaction the nonlinear spectroscopies, active and passive Adv. Phys. Chem. 83 43-87... 

Zhang, Z.-Y., Dixon, J. E. Active site labeling of the yersinia protein tyrosine phosphatase The determination of the pKa of active site cysteine and the function of the conserved histidine 402. Biochem. 32 (1993) 9340-9345. 

In situations where conserved internal markers caimot be used, such as in spills of essentially pure compounds, the evidence for enhanced biodegradation may have to be more indirect. Oxygen consumption, increases in microbial activity or population, and carbon dioxide evolution have all been used with success. 

The group of peptides known as tachykinins include substance P, substance K or neurokinin A, and neuromedin K, ie, neurokinin B, as well as a number of nonmammalian peptides. All members of this family contain the conserved carboxy-terrninal sequence Phe-X-Gly-Leu-Met-NH2, where X is an aromatic, ie, Phe or Tyr, or branched aliphatic, eg, Val or lie, amino acid. In general, this C-terminal sequence is cmcial for tachykinin activity (33) in fact, both the methionineamide and the C-terminal amide are cmcial for activity. The nature of the X residue in this sequence determines pharmacological identity (34,35) thus the substance P group contains an aromatic residue in this position, while the substance K group contains an aliphatic residue (33). 

Constraint control strategies can be classified as steady-state or dynamic. In the steady-state approach, the process dynamics are assumed to be much faster than the frequency with which the constraint control appHcation makes its control adjustments. The variables characterizing the proximity to the constraints, called the constraint variables, are usually monitored on a more frequent basis than actual control actions are made. A steady-state constraint appHcation increases (or decreases) a manipulated variable by a fixed amount, the value of which is determined to be safe based on an analysis of the proximity to relevant constraints. Once the appHcation has taken the control action toward or away from the constraint, it waits for the effect of the control action to work through the lower control levels and the process before taking another control step. Usually these steady-state constraint controls are implemented to move away from the active constraint at a faster rate than they do toward the constraint. The main advantage of the steady-state approach is that it is predictable and relatively straightforward to implement. Its major drawback is that, because it does not account for the dynamics of the constraint and manipulated variables, a conservative estimate must be taken in how close and how quickly the operation is moved toward the active constraints. 

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