Radial loops

Mahy NL, Perry PE, Gilchrist S, Baldock RA, Bickmore WA (2002) Spatial organization of active and inactive genes and noncoding DNA within chromosome territories. J Cell Biol 157 579-589 Mangenot S, Leforestier A, Vachette P, Durand D, Livolant F (2002) Salt-induced conformation and interaction changes of nucleosome core particles. Biophys J 82 345-356 Marsden MP, Laeimnh UK (1979) Metaphase chromosome structure evidence for a radial loop model. Cell 17 849-858... 

Rattner JB, Lin CC (1985) Radial loops and helical coils coexist in metaphase chromosomes. Cell 42 291-296... 

Type II topoisomerases are essential and function in replication, DNA repair, transcription, and chromosome segregation at mitosis.345,349 Yeast with a top2 mutation dies during mitosis with hopelessly entangled daughter chromosomes.353 A fluorescent antibody to eukaryotic topoisomerase II binds to chromosomes, probably at the bases of the radial loops... 

The 30 nm fiber is attached to a central protein scaffold in each chromosome in a series of radial loops. 

When chromosomes are depleted of histones, they are seen to have a central fibrous protein scaffold (or nuclear matrix) to which the DNA is attached in loops (Fig. 5). Therefore, in vivo it seems likely that the next order of packaging involves the attachment of the 30 nm fiber to multiple locations on this central protein scaffold in a series of radial loops. Little is known as to how this structure is organized. 

Fig. 6.2 Radial distribution function determined from a lOOps molecular dynamics simulation of liquid argon at a temperature of 100K and a density of 1.396gcm. ...

Retrofitting features of the more efficient reactor types have been the principal thmst of older methanol plant modernization (17). Conversion of quench converters to radial flow improves mixing and distribution, while reducing pressure drop. Installing an additional converter on the synthesis loop purge or before the final stage of the synthesis gas compressor has been proposed as a debotdenecking measure. 

The designer should attempt to keep the eapaeitors radially symmetrie from the ripple eurrent souree for both sides of the loop. 

FIGURE 12.31 A model for chromosome structure, human chromosome 4. The 2-um DNA helix is wound twice around histone octamers to form 10-um uucleosomes, each of which contains 160 bp (80 per turn). These uucleosomes are then wound in solenoid fashion with six uucleosomes per turn to form a 30-nm filament. In this model, the 30-nm filament forms long DNA loops, each containing about 60,000 bp, which are attached at their base to the nuclear matrix. Eighteen of these loops are then wound radially around the circumference of a single turn to form a miniband unit of a chromosome. Approximately 10 of these minibands occur in each chromatid of human chromosome 4 at mitosis. 

I All three radial distribution functions are calculated I within this loop k= 1,2,3 correspond to the functions (g-AA, g-AB,g-BB respectively. 

For j j =1 To 8 This outer loop varies the radial grid size to test convergence... 

The bubble size distribution is closely related to the hydrodynamics and mass transfer behavior. Therefore, the gas distributor should be properly designed to give a good performance of distributing gas bubbles. Lin et al. [21] studied the influence of different gas distributor, i.e., porous sinter-plate (case 1) and perforated plate (case 2) in an external-loop ALR. Figure 3 compares the bubble sizes in the two cases. The bubble sizes are much smaller in case 1 than in case 2, indicating a better distribution performance of the porous sinter-plate. Their results also show the radial profile of the gas holdup in case 1 is much flatter than that in case 2 at the superficial gas velocities in their work. 

Fig. 30 Radial distribution of inter-stem vectors connecting stems linked by loops. The folds connecting stems separated by the (100), <110) (the nearest neighbors), and (210), (200) (the second and the third nearest neighbors) in the hexagonal lattice vectors are quite dominant...

We also examined the fold statistics in this Ciooo system. The distribution of the inter-stem vectors connecting stems linked by the loops, and their radial distribution function again indicated that about 60-70% of the folds are short loops connecting the nearest or the second and third nearest stems, though the crystallization did not complete. The presence of local order in the under cooled melt in the present Ciooo system is also examined through the same local order P(r) parameter, the degree of bond orientation as a function of position r, but again we did not detect any appreciable order in the undercooled melt. 

The decision for each example is expressed as an "action-next state" pair. The "action" is a reference to executable Radial code, which consists of a sequence of Radial statements. These statements may contain references to external programs in various languages (this will be discussed further later). The "next state" describes the context to which control is to pass after the action is completed. For diagnostic expert systems, such as TOGA, the next state will usually be the "goal" state of the module. This passes control back to the calling module. For procedural expert systems, such as robotics and instrumentation control applications, the control will be transferred between several states within a module to Implement looping. 

After consideration of all the technical and economic aspects of expanding the existing system versus installing a completely new system, the Honeywell system was replaced by a TRK system of ouch greater speed and capacity (see Figure S). Also added waa a SCADA console at each GC control roam to allow the CC operators to monitor well pad operationa and if necessary to take control action. Another addition was a revised microwave communications network thet includes the well peds. The system has an inner dual redundant loop for the most critical communications path between GCs, HOC, and CPS, with redundant radial shots from each GC to its associated well pads. 

Figure 27-5 (A, B) Two possible models of the 30-nm chromatin fiber.55 (A) Thoma et al.85 (B) Woodcock et al.6i 87 The fully compacted structure is seen at the top of each figure. The bottom parts of the figures illustrate proposed intermediate steps in the ionic strength-induced compaction. (C) Possible organization of the DNA within a metaphase chromosome. Six nucleosomes form each turn of a solenoid in the 30-nm filament as in (A). The 30-nm filament forms 30 kb-loop domains of DNA and some of these attach at the base to the nuclear matrix that contains topoisomerase II. About ten of the loops form a helical radial array of 250-nm diameter around the core of the chromosome. Further winding of this helix into a tight coil 700 nm in diameter, as at the top in (C), forms a metaphase chromatid. From Manuelidis91.

Fig. 3. Details of the seven-stranded /1-sheet and associated structures (A and B) in the post-rigor conformation and (C and D) in the pre-powerstroke conformation. The orientation of A and C is at right angles to that shown in Fig. 2. When attached to actin, it corresponds to that shown in Fig. 5B. The colors are as in Fig. 2. The views shown in B and D are at right angles to A and C looking out radially from the axis of the actin helix. Note the kink in the relay helix shown in C and D that leads to a 60° rotation of the converter domain. This in turn rotates the lever arm 60°. The P-loop (which constitutes the ATP-binding site) and the adjoining a-helix are shown in yellow. The flanking switch sequences (1 and 2) are also shown. The strands of the /1-sheet are numbered from the N-terminal (distal) end of the sheet. The lower part of strand 5 (light blue) constitutes switch 2. In the post-rigor state, switch 2 lies out of the plane of the /1-sheet (open) and in the pre-powerstroke state switch 2 is in the plane of the /1-sheet (closed).

Small bubbles and flow uniformity are important for gas-liquid and gas-liquid-solid multiphase reactors. A reactor internal was designed and installed in an external-loop airlift reactor (EL-ALR) to enhance bubble breakup and flow redistribution and improve reactor performance. Hydrodynamic parameters, including local gas holdup, bubble rise velocity, bubble Sauter diameter and liquid velocity were measured. A radial maldistribution index was introduced to describe radial non-uniformity in the hydrodynamic parameters. The influence of the internal on this index was studied. Experimental results show that The effect of the internal is to make the radial profiles of the gas holdup, bubble rise velocity and liquid velocity radially uniform. The bubble Sauter diameter decreases and the bubble size distribution is narrower. With increasing distance away from the internal, the radial profiles change back to be similar to those before contact with it. The internal improves the flow behavior up to a distance of 1.4 m. 

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