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Termination premature

This inherent feature of ECM, whereby an equiHbriumgap width is obtained, is used widely in ECM for reproducing the shape of the cathode tool on the workpiece. (J) Under short-circuit conditions the gap width goes to zero. If process conditions such as too high a feed rate arise the equiHbrium gap may be so small that contact between the two electrodes ensues. This condition causes a short circuit between the electrodes and hence premature termination of machining. [Pg.309]

Anionic polymerization offers fast polymerization rates on account of the long life-time of polystyryl carbanions. Early studies have focused on this attribute, most of which were conducted at short reactor residence times (< 1 h), at relatively low temperatures (10—50°C), and in low chain-transfer solvents (typically benzene) to ensure that premature termination did not take place. Also, relatively low degrees of polymerization (DP) were typically studied. Continuous commercial free-radical solution polymerization processes to make PS, on the other hand, operate at relatively high temperatures (>100° C), at long residence times (>1.5 h), utilize a chain-transfer solvent (ethylbenzene), and produce polymer in the range of 1000—1500 DP. [Pg.517]

Premature termination of Task Definition / Strategy selection... [Pg.184]

In patients having Parkinson s disease, both entacapone and tolcapone potentiate the therapeutic effect of L-dopa and prolong the daily ON time by 1-2 h. In the clinic, COMT inhibitors have been well tolerated, and the number of premature terminations has been low. In general, the incidence of adverse events has been higher in tolcapone-treated patients than in entacapone-treated patients. The main events have comprised of dopaminergic and gastrointestinal problems [2,3]. [Pg.338]

A nonsense codon may appear that would then result in the premature termination of amino acid incorporation into a peptide chain and the production of only a fragment of the intended protein molecule. The probabihty is high that a premamrely terminated protein molecule or peptide fragment will not function in its assigned role. [Pg.361]

With the progress of electrolysis the concentration of aluminum (and of other base impurities) increases as a result of this the contamination of the cathode deposit also increases. A stage may be reached when the contamination exceeds acceptable limits, thereby calling for a premature termination of electrolysis. It is for this reason that it is desirable to purify and recycle the electrolyte wherever possible so that electrorefining could be conducted for extended periods, without having to contend with the problem of excessive contamination. [Pg.716]

Genomic DNA is much more complex than cDNA. Since cDNAs are synthesized in the laboratory from mRNAs using reverse transcriptase, they are no more diverse than the number of mRNAs present at the time of isolation. However, only about 2% of the mammalian genome codes for the synthesis of proteins and their mRNAs. Thus genomic DNA libraries are at least 50 times more diverse than cDNA libraries. cDNA libraries are not easier to make, however, both because of the inherent instability of mRNA compared to DNA and because reverse transcriptase prematurely terminates when copying long mRNAs. [Pg.253]

Banga et al. [in State of the Art in Global Optimization, C. Floudas and P. Pardalos (eds.), Kluwer, Dordrecht, p. 563 (1996)]. All these methods require only objective function values for unconstrained minimization. Associated with these methods are numerous studies on a wide range of process problems. Moreover, many of these methods include heuristics that prevent premature termination (e.g., directional flexibility in the complex search as well as random restarts and direction generation). To illustrate these methods, Fig. 3-58 illustrates the performance of a pattern search method as well as a random search method on an unconstrained problem. [Pg.65]

The 19-mer sequence must not contain four or five consecutive T or A residues, because this would act as a premature termination of transcription signal for the poly III complex. [Pg.188]

Developmentally, thyroid hormones interact with sex hormones such that hypothyroidism prolongs the critical period for testosterone-induced defeminization (see below) [3] in contrast, the hyperthyroid state prematurely terminates the sensitivity to testosterone [3]. Undoubtedly, an important link in these and other effects is synapse formation. Hypothyroidism increases synaptic density, at least transiently [3]. Interesting parallels with synapse formation are reported for learning behavior in rats neonatal hypothyroidism impairs learning ability, whereas hyperthyroidism accelerates learning initially, followed by a decline later in life [3]. [Pg.854]

PETRACEK, M.E., NUYGEN, T., THOMPSON, W.F., DICKEY, L.F., Premature termination codons destabilize ferredoxin-1 mRNA when ferredoxin-1 is translated, Plant J., 2000,21,563-569. [Pg.93]

This enzyme from E. coli is a tetramer of four identical subunits, each of molecular weight 116,500. Amber and ochre (premature termination) mutants of the enzyme provide a number of enzymically inactive, incomplete peptide chains, identical in sequence with the N-term nal part of the wild-type chains. A subset of these N-terminal peptides, called acceptor peptides, can combine with so-called wild-type chain, to restore enzymic activity (Ullmann et al., 1965, 1967 Ullmann and Perrin, 1970 see also the review by Zabin and Villarejo, 1975). Goldberg (1969) suggested that the acceptor peptides and the independent nucleation centers as evidenced by the following facts ... [Pg.63]

Wakamatsu N, Hayashi M, Kawai H, Kondo H, Gotoda Y, et al. 1999. Mutations producing premature termination of translation and an amino acid substitution in the sterol 27-hydroxylase gene cause cerebrotendinous xanthomatosis associated with parkinsonism. J Neurol Neurosurg Psychiatry 67 195-198. [Pg.90]

Upon encountering a stop codon on the mRNA, the ribosome will halt incorporation of further amino acids into the polypeptide as there is no tRNA complementary to a stop codon (UAG, UGA, UAA). In order to liberate the polypeptide, the ester bond between the peptide and the tRNA residing in the P site has to be hydrolyzed — a reaction that is also catalyzed in the peptidyltransferase center. It is critical for protein synthesis that peptide release is tightly coupled to the presence of a stop codon in the decoding center to avoid premature termination resulting in shortened, nonfunctional proteins. Both functions, recognizing the stop codon and triggering... [Pg.372]

Puromycin inhibits both prokaryotic and eukaryotic translation by binding to the A site. Peptidyl transferase attaches the peptide to puromycin, and the peptide with puromycin attached at the C-terminus is released, prematurely terminating chain growth. [Pg.54]

There have been many studies that have examined transcription on chromatin templates in vitro. The general sense is that transcription does occur through the nucleosomes, but there is substantial premature termination and repression. An example of earlier experiments in this regard is the work of Wasylyk and Chambon, 1979 [76] in which histones were reconstituted on SV40 form 1 DNA and... [Pg.474]

Fig. 26 Dry thickness of poly(acryl amide) as a function of the position on the silica substrate prepared by slow ( ) and fast ( ) removal of the polymerization solution by utilizing the method depicted in Fig. 24. The inset shows the dry poly(acryl amide) thickness as a function of the polymerization time. Note that both data sets collapse on a single curve at short polymerization times. Regardless of the drain speed, the brush thickness increases linearly at short polymerization times and levels off at longer polymerization times. The latter behavior is associated with premature termination of the growing polymers... Fig. 26 Dry thickness of poly(acryl amide) as a function of the position on the silica substrate prepared by slow ( ) and fast ( ) removal of the polymerization solution by utilizing the method depicted in Fig. 24. The inset shows the dry poly(acryl amide) thickness as a function of the polymerization time. Note that both data sets collapse on a single curve at short polymerization times. Regardless of the drain speed, the brush thickness increases linearly at short polymerization times and levels off at longer polymerization times. The latter behavior is associated with premature termination of the growing polymers...
The Sponsor may terminate this Agreement immediately upon notice in writing to the NHS Trust for reasons not falling within clauses 12.1, 12.2 or 12.3 above, save that in such circumstances the provisions of clause 12.6 below shall also apply. In all such circumstances the Sponsor shall confer with the Site Principal Investigator and use its best endeavours to minimise any inconvenience or harm to Clinical Trial Subjects caused by the premature termination of the Clinical Trial. [Pg.798]

In a simplifled form, the firework rocket trajectory can be discussed in terms of basic equations of motion, simplifled even further by the fact that the rocket rises in the air for a few seconds after which the flight is prematurely terminated when the pyrotechnic effects are released. [Pg.50]

Eukaryotic DNA contains sequences recognized as termination signals in E. coli, resulting in premature termination of transcription and a truncated protein. Also, there are differences in codon preference affecting translation, which may ultimately... [Pg.4]


See other pages where Termination premature is mentioned: [Pg.162]    [Pg.363]    [Pg.179]    [Pg.5]    [Pg.19]    [Pg.24]    [Pg.13]    [Pg.112]    [Pg.199]    [Pg.167]    [Pg.295]    [Pg.720]    [Pg.76]    [Pg.88]    [Pg.227]    [Pg.244]    [Pg.245]    [Pg.583]    [Pg.585]    [Pg.286]    [Pg.181]    [Pg.367]    [Pg.373]    [Pg.69]    [Pg.277]    [Pg.475]    [Pg.305]    [Pg.363]    [Pg.4]    [Pg.73]   
See also in sourсe #XX -- [ Pg.223 , Pg.224 ]

See also in sourсe #XX -- [ Pg.5 ]




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