SummaryA screen for novel symbiotic mutants of the nitrogenfixing legume symbiont Sinorhizobium meliloti uncovered a crucial role for the putative response regulator FeuP in the symbiotic infection process. Transcriptome analysis shows that FeuP controls the transcription of at least 16 genes, including ndvA, which encodes an ATP-dependent exporter of cyclic b glucans. Loss of feuP function gives rise to traits associated with cyclic b glucan biosynthetic defects, including poor growth and motility under hypoosmotic conditions, and the inability to invade plant tissue during the early stages of symbiotic infection. Analysis of cyclic glucans indicates that the feuP mutant is able to synthesize intracellular cyclic b glucans, but is unable to export them. Cyclic b glucan export can be restored to feuP mutant cells by constitutive expression of ndvA; likewise, the symbiotic phenotype of a feuP mutant is rescued by ectopic ndvA expression. We further show that the linked sensor kinase gene, feuQ, is also important for modulating ndvA transcription, and that signalling through the FeuP/FeuQ pathway is responsive to extracellular osmotic conditions, with low osmolarity stimulating ndvA expression.

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The versatility/specialization debate in criminology has important theoretical, research, and juvenile/criminal justice ramifications. Although offenders are mostly versatile, there is important evidence of specialization, but much of this evidence is derived from highly technical statistical approaches. Drawing on data from a cohort of serious delinquents committed to the California Youth Authority, logistic regression models revealed robust evidence for criminal specialization net the effects of behavioral and demographic controls. Prior homicide was associated with a 1,467% increased likelihood of being currently adjudicated for a homicide offense. Similar prior–current involvement in robbery (294% increased likelihood), aggravated assault (200%), burglary (148%), and drug sales (736%) was found. Logistic regression with odds ratios provides intuitive, valuable estimates of specialization in offending whereby prior involvement in a specific form of delinquency dramatically increases the likelihood of current involvement in the same form of crime.

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Atomic layer deposition (ALD) is widely used in the semiconductor industry to provide atomic level control over film thicknesses and layer conformality. Here, the authors report the thermal (332 °C) ALD of thin amorphous alumina films (0.5–41.0 nm) deposited using water and trimethylaluminum precursors. Alumina deposition was optimized by varying the dose and purge times for both precursors with an eye toward obtaining uniform film thicknesses and constant growth per cycle. Films were characterized by x-ray photoelectron spectroscopy and spectroscopic ellipsometry (from 191 to 1688 nm). The subsequent workup of the SE data was based on a multisample analysis. It considered Cauchy and Sellmeier functions and accounted for surface roughness. This modeling yielded an optical function for ALD alumina over the measured wavelength range. The authors recommend the optical function determined from the Sellmeier model.