Kinetics of the reaction between phosphorus vapour and oxygen: comparison of the effect of hydrogen, deuterium and helium on the lower explosion limit of phosphorus-oxygen mixtures. Displacement of the explosion limits by the action of ultraviolet light. Study of the photochemical initiation of the stable reaction between phosphorous vapour and oxygen

The effect of the foreign gases Hydrogen, Helium and Deuterium on the lover explosion limit of P4-02 mixtures has been studied, and the values for the inert gas effect determined in each case. Comparison of these values showed conclusively that hydrogen ha: a greater inert gas effect than is predicted by theory, A partial explanation of this may lie in the assumptions made as to the nature and physical constants of the chain carriers.The absorption spectrum of phosphorus vapour was obtained for different pressures of phosphorus vapour. Definite absorption was seen to take place in the region of and below the mercury line at 2537A °.Illumination of P4 -02 mixtures at pressures below the lower explosion limit produced two effects, viz. (a) a displacement of the lower limit towards smaller pressures (b) a reaction between the P4 and 02 molecules below the lower limit.Further experimental work was carried out on the displacement of the lower limit in order to test the statement that the explosion limits in a chain reaction are independent of the rate of initiation of the chains. loo During this work it was shown that the displacement is not permanent but slowly decays on allowing the reaction mixtures to stand before proceeding to explosion. A period of five to six minutes is necessary before normal conditions are regained. Illumination of P4 vapour alone resulted in a displacement of the lower limit of only half the value of that obtained when oxygen was present, although the slopes of the corresponding decay curves were similar. Moreover the displacement was the same for different pressures of oxygen, although it was obviously effected by a change in the condition of the walls.All the evidence obtained which was based on the transfer experiments, showed that the displacement of the lower limit was a wall effect and was not due to the production of active centres in the gas. This wall effect was due in the first case to the formation of P2 molecules from the P4 molecules.Illumination of phosphorus- oxygen mixtures above the upper explosion limit resulted in a displacement of this limit towards higher pressures. It was suggested that the explosion limit found under normal conditions is low owing to the fact that the rate of starting of the chains is too slow for the relationship predicted by chain theory to hold.The stable reaction between P4 -02 molecules initiated by the ultraviolet light was shown to be a chain reaction, the kinetics of which was studied and the rate of reaction was found to be given by =_ d[02]/dt = [P4][02]2 x I x constant.The effect of inert gases on the reaction rate was studied and it was shown that the velocity constant was independent of the concentration of inert gas present.Phosphorus vapour on exposure to ultraviolet light was shown to be converted into red phosphorus. The rate of transformation was measured and the reaction found to be approximately unimolecular

Evolution of an ancient protein function involved in organized multicellularity in animals.

To form and maintain organized tissues, multicellular organisms orient their mitotic spindles relative to neighboring cells. A molecular complex scaffolded by the GK protein-interaction domain (GKPID) mediates spindle orientation in diverse animal taxa by linking microtubule motor proteins to a marker protein on the cell cortex localized by external cues. Here we illuminate how this complex evolved and commandeered control of spindle orientation from a more ancient mechanism. The complex was assembled through a series of molecular exploitation events, one of which - the evolution of GKPID's capacity to bind the cortical marker protein - can be recapitulated by reintroducing a single historical substitution into the reconstructed ancestral GKPID. This change revealed and repurposed an ancient molecular surface that previously had a radically different function. We show how the physical simplicity of this binding interface enabled the evolution of a new protein function now essential to the biological complexity of many animals

REM density in the differential diagnosis of psychiatric from medical-neurologic disorders: A replication

The discriminatory power of rapid eye movement (REM) density in 61 outpatients with medical, neurologic, and psychiatric disorders and 8 noncase controls was assessed. REM density was significantly lower in a group of patients with medical-neurologic disease as compared with psychiatric and control subjects without evidence for such disease. Furthermore, low scores discriminated depressions occurring in the context of somatic disease when compared with those in the absence of such disease. The differences between groups were not accounted for by age or sex. The cutoff REM density score of 12.56, based on the 99% lower confidence limit of the noncase controls, provided the highest sensitivity (0.82) without loss of specificity (0.80). It was concluded that REM density may have merit as a general measure of diffuse central nervous system pathology, whether primary or secondary to widespread systemic disease. The findings of Kupfer's group are upheld and extended to a broader medical and neuropsychiatric population than in the original Pittsburgh study.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/24174/1/0000433.pd

Hierarchical metabolomics demonstrates substantial compositional similarity between genetically-modified and conventional potato crops

There is current debate whether genetically modified (GM) plants might contain unexpected, potentially undesirable changes in overall metabolite composition. However, appropriate analytical technology and acceptable metrics of compositional similarity require development. We describe a comprehensive comparison of total metabolites in field-grown GM and conventional potato tubers using a hierarchical approach initiating with rapid metabolome “fingerprinting” to guide more detailed profiling of metabolites where significant differences are suspected. Central to this strategy are data analysis procedures able to generate validated, reproducible metrics of comparison from complex metabolome data. We show that, apart from targeted changes, these GM potatoes in this study appear substantially equivalent to traditional cultivars

Best Practices for Cataloging DVD-Video and Blu-ray Discs Using RDA and MARC21

Best Practices for Cataloging DVD-video and Blu-ray Discs Using RDA and MARC21 builds upon the work of the 2008 Guide to Cataloging DVD and Blu-ray Discs Using AACR2r and MARC21, which in turn updated the 2002 Guide to Cataloging DVDs Using AACR2r Chapters 7 and 9 created by the DVD Cataloging Task Force of OLAC. The focus of this new document is to provide a set of “best practice” recommendations rather than a step-by-step instruction manual for cataloging DVD-video and Blu-ray Discs. One reason for this shift is that RDA cataloging practice is far from settled, particularly in regard to special format materials. Best practice recommendations will likely be easier to manage as RDA instructions evolve. This document is intended for use with Resource Description and Access (RDA) and the MARC21 Format for Bibliographic Data. It should not be considered a substitute for the RDA Toolkit. The best practice recommendations and cataloging examples presented in the document are intended only to clarify RDA principles and instructions used in cataloging DVD-video and Blu- ray Disc formats

Rare Copy Number Variants in \u3cem\u3eNRXN1\u3c/em\u3e and \u3cem\u3eCNTN6\u3c/em\u3e Increase Risk for Tourette Syndrome

Tourette syndrome (TS) is a model neuropsychiatric disorder thought to arise from abnormal development and/or maintenance of cortico-striato-thalamo-cortical circuits. TS is highly heritable, but its underlying genetic causes are still elusive, and no genome-wide significant loci have been discovered to date. We analyzed a European ancestry sample of 2,434 TS cases and 4,093 ancestry-matched controls for rare (\u3c 1% frequency) copy-number variants (CNVs) using SNP microarray data. We observed an enrichment of global CNV burden that was prominent for large (\u3e 1 Mb), singleton events (OR = 2.28, 95% CI [1.39–3.79], p = 1.2 × 10−3) and known, pathogenic CNVs (OR = 3.03 [1.85–5.07], p = 1.5 × 10−5). We also identified two individual, genome-wide significant loci, each conferring a substantial increase in TS risk (NRXN1 deletions, OR = 20.3, 95% CI [2.6–156.2]; CNTN6 duplications, OR = 10.1, 95% CI [2.3–45.4]). Approximately 1% of TS cases carry one of these CNVs, indicating that rare structural variation contributes significantly to the genetic architecture of TS

International meta-analysis of PTSD genome-wide association studies identifies sex- and ancestry-specific genetic risk loci.

The risk of posttraumatic stress disorder (PTSD) following trauma is heritable, but robust common variants have yet to be identified. In a multi-ethnic cohort including over 30,000 PTSD cases and 170,000 controls we conduct a genome-wide association study of PTSD. We demonstrate SNP-based heritability estimates of 5-20%, varying by sex. Three genome-wide significant loci are identified, 2 in European and 1 in African-ancestry analyses. Analyses stratified by sex implicate 3 additional loci in men. Along with other novel genes and non-coding RNAs, a Parkinson's disease gene involved in dopamine regulation, PARK2, is associated with PTSD. Finally, we demonstrate that polygenic risk for PTSD is significantly predictive of re-experiencing symptoms in the Million Veteran Program dataset, although specific loci did not replicate. These results demonstrate the role of genetic variation in the biology of risk for PTSD and highlight the necessity of conducting sex-stratified analyses and expanding GWAS beyond European ancestry populations

Best Practices for Cataloging DVD-Video and Blu-ray Discs Using RDA and MARC21 Version 1.1

Purpose Best Practices for Cataloging DVD-video and Blu-ray Discs Using RDA and MARC21 builds upon the work of the 2008 Guide to Cataloging DVD and Blu-ray Discs Using AACR2r and MARC21, which in turn updated the 2002 Guide to Cataloging DVDs Using AACR2r Chapters 7 and 9 created by the DVD Cataloging Task Force of OLAC. The focus of this new document is to provide a set of “best practice” recommendations rather than a step-by-step instruction manual for cataloging DVD-video and Blu-ray Discs. One reason for this shift is that RDA cataloging practice is far from settled, particularly in regard to special format materials. Best practice recommendations will likely be easier to manage as RDA instructions evolve. This document is intended for use with Resource Description and Access (RDA) and the MARC21 Format for Bibliographic Data. It should not be considered a substitute for the RDA Toolkit. The best practice recommendations and cataloging examples presented in the document are intended only to clarify RDA principles and instructions used in cataloging DVD-video and Blu- ray Disc formats. The opening section provides a general overview of DVD and Blu-ray technology, disc characteristics, plus a comparison with compact disc (CD) technology. A brief introduction to RDA follows, to provide a basic frame of reference for the document. Since most libraries are still encoding data in MARC21, the main part of the document is generally arranged by RDA element in the order they are encountered in a MARC21 record. Each section includes examples that reflect the principles outlined in the document. Examples use ISBD as the presentation format. A table outlining recommended description and encoding of DVD-Video and Blu-ray Disc attributes is given in the appendix. A list of resources and a selection of full MARC21 record examples illustrating common situations encountered in DVD-Video and Blu-ray Disc cataloging completes the document