Last year, the NICTA L4.verified project produced a formal machine-checked Isabelle/HOL proof that the C code of the seL4 OS microkernel correctly implements its abstract implementation. This papers gives a brief overview of the proof together with its main implications and assumptions, and paints a vision on how this verified kernel can be used for gaining assurance of overall system security ...

A rare clinical isolate of Streptococcus pneumoniae, highly resistant to telithromycin, contained erm(B) with a truncated leader peptide and a mutant ribosomal protein L4. By transformation of susceptible strains, this study shows that high-level telithromycin resistance is conferred by erm(B), wild type or mutant, in combination with a (69)GTG(71)-to-TPS mutation in ribosomal protein L4.

We revisit recent work of Heath-Brown on the average order of the quantity r(L1(x)) · · · r(L4(x)), for suitable binary linear forms L1, . . . , L4, as x = (x1, x2) ranges over quite general regions in Z. In addition to improving the error term in Heath-Brown’s estimate we generalise his result to cover a wider class of linear forms.

The straight leg raising test and the femoral nerve stretch test exert traction on the sciatic and femoral nerve, and the lumbosacral plexus and roots. In 40 patients with a suspected L4/5 disc protrusion, ipsilateral sciatica was induced by the femoral nerve stretch test. We believe that this is a pathognomonic sign of a lateral protrusion at L4/5 level.

Posteroanterior stiffness of the lumbar spine is influenced by factors, including trunk muscle activity and intra-abdominal pressure (IAP). Because these factors vary with breathing, this study investigated whether stiffness is modulated in a cyclical manner with respiration. A further aim was to investigate the relationship between stiffness and IAP or abdominal and paraspinal muscle activity....

It has been reported that disaccharides of the glycosaminoglycans (GAGs), heparin, or heparan sulfate suppress the production of cytokines. Therefore, we examined the effects of GAGs (keratan sulfate, hyaluronan, chondroitin, chondroitin sulfate, and heparin sulfate) disaccharides on production of interleukin (IL)-12, a pivotal cytokine in the Th-1 type immune system. Among the GAG disaccharide...

To assess the changes in the curvature of the spinal column in the supine position during pregnancy, we studied seven pregnant (32-37 weeks of pregnancy) and seven non-pregnant women using magnetic resonance imaging. T1-weighted sagittal midline magnetic resonance images of the spinal column were obtained with subjects in the supine position with left tilt. There was no significant difference i...

The ribosomal proteins L4 and L22 form part of the peptide exit tunnel in the large ribosomal subunit. In Escherichia coli, alterations in either of these proteins can confer resistance to the macrolide antibiotic, erythromycin. The structures of the 30S as well as the 50S subunits from each antibiotic resistant mutant differ from wild type in distinct ways and L4 mutant ribosomes have decrease...

BACKGROUND The association of lumbar spine instability between laminectomy and laminotomy has been clinically studied, but the corresponding in vitro biomechanical studies have not been reported. We investigated the hypothesis that the integrity of the posterior complex (spinous process-interspinous ligament-spinous process) plays an important role on the postoperative spinal stability in decom...

PURPOSE The authors investigated the effect of lumbar facet tropism (FT) on intervertebral disc degeneration (DD), facet joint degeneration (FJD), and segmental translational motion. MATERIALS AND METHODS Using kinetic MRI (KMRI), lumbar FT, which was defined as a difference in symmetry of more than 7 degrees between the orientations of the facet joints, was investigated in 900 functional spi...