Polymerase slippage during DNA synthesis by the Klenow fragment of DNA polymerase across A, C, G and T repeats (30 bases) has been studied. Within minutes, duplexes that contain only repeats (30 bp) expand dramatically to several hundred base pairs long. Rate comparisons in a repeat duplex when one strand was expanded as against that when both strands were expanded suggest a model of migrating ...

This paper introduces a new approach to the design and control of a four-degree-of-freedom (4DOF) vehicle. This vehicle can travel sideways and it can negotiate tight turns easily. Existing 4DOF vehicles have been found difficult to control 2. The compliant linkage because of their overcon-strained nature. These difficulties As explained above, the key element in any workable MDOF translate int...

Technology to enable core sample acquisition from a low-mass rover on slopes is being developed. A rotary percussive coring tool was integrated onto a low-mass rover and sensing, control, and simulation technologies are being developed. Initial results indicate that coring with modest rover slippage

Transcriptional slippage is a class of error in which ribonucleic acid (RNA) polymerase incorporates nucleotides out of register, with respect to the deoxyribonucleic acid (DNA) template. This phenomenon is involved in gene regulation mechanisms and in the development of diverse diseases. The bacteriophage λ N protein reduces transcriptional slippage within actively growing cells and in vitro. ...

The EDRES software, developed by the CNES of Toulouse, is a simulation tool for planetary mobile robots. It is intended to validate control algorithms and onboard software for future exploration missions, such as ExoMars. To enhance the relevance of the simulation, we have integrated a terramechanic contact model, in order to study the influence of slippage and sinkage on motion estimation and ...

The family Potyviridae encompasses ~30% of plant viruses and is responsible for significant economic losses worldwide. Recently, a small overlapping coding sequence, termed pipo, was found to be conserved in the genomes of all potyvirids. PIPO is expressed as part of a frameshift protein, P3N-PIPO, which is essential for virus cell-to-cell movement. However, the frameshift expression mechanism ...

DNA containing repetitive sequences displays richer dynamics than heterogeneous sequences. In the genome the number of repeat units of repetitive sequences, known as microsatellites, may vary during replication by DNA slippage and their expansion gives rise to serious disorders. We studied the mechanical properties of repetitive DNA using dynamic force spectroscopy and found striking difference...

BACKGROUND Re-operations after laparoscopic adjustable gastric banding operation (LAGB) are band-associated or due to complications of the access-port. Symptoms, diagnostics, operations, and follow-up of patients with re-operations were analyzed. METHODS Between December 1996 and January 2002, 250 morbidly obese patients were treated with LAGB and prospectively evaluated using a standardized ...

OBJECTIVE To measure the orientation of the facet joints of cervical spine (C-spine) segments in the sagittal plane, known as the pedicle-facet (P-F) angle, and to use these measurements to evaluate the relationship between the P-F angle and the amount of vertebral anterolisthesis in patients with degenerative cervical spondylolisthesis (DCS). METHODS A retrospective case-control study was pe...