Replicative speed

The differentiation of role between the molecules looks like symmetry breaking. When initially two states are equally possible, and later only one of them is selected, it is said that the symmetry is broken. In the differentiation of roles of molecules studied here, however, the molecules have different characters as to the replication speed from the beginning. Here a difference in one character (i.e., the replication speed) is transformed into the difference in the control behavior and in the role as a carrier of heredity. In other words, a characteristic with already broken symmetry is transformed into a different type of symmetry breaking. This kind of transformation of one character s difference to another is often seen in biology, as we have already discussed in the study of morphogenesis and sympatric speciation [16,17]. 

It is clear that simulation models can replicate a complex production system. They can be used to indicate the level of shared resources needed by the operation (e.g. forklift trucks or operators), the speed of lines, sizes of vessels or storage tanks, etc. 

A bench top polysulfone hollow fiber membrane (0.0325m ) with molecular weight cutoff (MWCO) of 30K (A/G Technology Corp., Needham MA) was used (24). UF was run in a total recycle mode at a rate of 1.2 L/min (flow speed of 0.73 m/sec), cross membrane pressure of 25 PSIG and 10 + 1°C. PE permeability is expressed as the fraction of PEU/mL in the permeate to PEU/mL in the retentate. Data presented are representative of at least duplicate replications. 

Laboratory rotors have been used to evaluate the drag resistance of immersed surfaces as well. The rotational frequency of the innermost cylinder is adjusted to the relevant speed (monitored by a tachometer) and after about 30 minutes of flow stabilisation a 50 Nm strain gauge transducer picks up the torque, M,. All measurements are based on the average of three replicate tests. A sketch of the set-up is shown in Figure 13 details on the set-up and calculations are described in Weinell et al. (2003). 

Fig. I. Relationship between concurrent measurements of the rate of ammonia loss made using the wind tunnel and micrometeorological mass balance methods during an experiment in which the mean air speed through the tunnels was adjusted to maintain a value within 20% of the mean ambient wind speed. Rates of loss measured using the wind tunnels are the means of four replicates, the bars around each point indicating the 95% confidence limits (reproduced from ref. 12).

Dudoit S, Yang YH, Callow MJ, Speed TP. 2002. Statistical methods for identifying differentially expressed genes in replicate cDNA microarray experiments. Statistica Sinica 12 111. 

D. DNA replication is regulated as a balance between high speed and efficiency (pro-cessivity) and the need for high fidelity. 

The TS of the compacted samples was determined by transverse compression with a custom-built tensile tester. Tensile failure was observed for all the rectangular compacts when compressed between flat-faced platens at a speed ranging between 0.006 and 0.016 mm/sec. Platen speed was adjusted between materials to maintain a time constant of 15 2 seconds to account for viscoelastic differences the constant is the time between the sample break point and when the measured force equals Fbreak/e in the force versus time profile, where the denominator is the mathematical e. Specially modified punch and die sets permitted the formation of square compacts with a centrally located hole (0.11 cm diameter) that acted as a stress concentrator during tensile testing. This capability permitted the determination of a compromised compact TS and thus facilitated an assessment of the defect sensitivity of each compacted material. At least two replicate determinations were performed for each mechanical testing procedure and mean values are reported. 

To test the foregoing dimensionless relationship, two powders (Avicel Pl 1101, a ductile, viscoelastic material, and Emcompress, a brittle material, blended with 0.5% magnesium steaiate) were compressed on the PressterTw, a single-station mechanical replicator of rotary tablet presses. In the first set of experiments, a 16-station Manesty Betapress (a research-scale press) was simulated at two speeds, 60 and 100 rpm. In the second set, a 36-station Fette P2090 (a medium-scale production press) was simulated at two speeds, 55.8 and 70 rpm. It should be noted that 100 rpm of the Beta-press corresponds to 55.8 rpm of the Fette 2090 in terms of the linear speed of the turret. Basic parameters for the two tablet presses arc presented in Table 3. 

Although the action of the DNA polymerase I, according to Eq. 27-3, provided a straightforward way to form a complementary strand of DNA, it did not explain how double-stranded DNA could be copied. One problem is that the two strands must be separated and unwound. If unwinding and replication occured at a single replication fork in the DNA, as indicated by Caims experiment, the entire molecule would have to spin at a speed of 300 revolutions per second to permit replication of the E. coli chromosome in 20 min. It also required that some kind of a swivel, or at least a... 

Like Soxhlet, sonication is also recognized as an established conventional method, although it is not as widely used. Limited research has focused on sonication per se or its comparison with Soxhlet. Qu et al. [13] developed a method using sonication with methanol for the extraction of linear alkylbenzene sulfonate (LAS) in plant tissues (rice stems and leaves). Both efficiency and accuracy were found to be high. The mean recovery was 89% (84 to 93% for LAS concentration of 1 to 100 mg/kg), and the relative standard deviation (RSD) was 3% for six replicate analyses. Its advantages over Soxhlet extraction were speed (1 hour), less solvent consumption, and smaller sample requirement (2 to 3 g). 

The Olsen method is extremely sensitive to changes in operating conditions, and unless care is taken, reproducible results will not be obtained. It is therefore imperative that all the extractions are done at the same temperature, at the same shaking speeds, and on the same shaker each time if results are to be compared between soils. For example, it is important even to adopt a standard method of filtration. The one we use is to swirl the flask briskly, add soil extract to the filter paper, and then replace the flask on the bench. Proceed in exactly the same way with the next soil replicate. If a top up is required, all flasks should be topped up in the same way. Analyze the same day if possible, although extracts may be frozen. 

Table 4.4 Gene expression of desaturase (D) and elongase (E) genes differently expressed between D. melanogaster lines selected for fast and slow mating speeds (Mackay et al., 2005). The cytological localization (cyt) of the genes is reported. Values are means (s.e.) of three replicates per fly.

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