71 research outputs found
Electronic cigarettes: A position statement from the Thoracic Society of Australia and New Zealand*
The TSANZ develops position statements where insufficient data exist to write formal clinical guidelines. In 2018, the TSANZ addressed the question of potential benefits and health impacts of electronic cigarettes (EC). The working party included groups focused on health impacts, smoking cessation, youth issues and priority populations. The 2018 report on the Public Health Consequences of E-Cigarettes from the United States NASEM was accepted as reflective of evidence to mid-2017. A search for papers subsequently published in peer-reviewed journals was conducted in August 2018. A small number of robust and important papers published until March 2019 were also identified and included. Groups identified studies that extended, modified or contradicted the NASEM report. A total of 3793 papers were identified and reviewed, with summaries and draft position statements developed and presented to TSANZ membership in April 2019. After feedback from members and external reviewers, a collection of position statements was finalized in December 2019. EC have adverse lung effects and harmful effects of long-term use are unknown. EC are unsuitable consumer products for recreational use, part-substitution for smoking or long-term exclusive use by former smokers. Smokers who require support to quit smoking should be directed towards approved medication in conjunction with behavioural support as having the strongest evidence for efficacy and safety. No specific EC product can be recommended as effective and safe for smoking cessation. Smoking cessation claims in relation to EC should be assessed by established regulators
Stereochemistry of Ethylenediaminetetraacetato Complexes. II. The Structure of Crystalline Rb[Fe(OH 2
The Treatment Of Data Collected With A Single-Crystal Diffractometer
Iron was inserted into the known crystal structure of the bismuth phosphate oxide Bi6.67(PO4)4O4 to ascertain its location in the vacancies associated with the bismuth ion located at the origin of the unit cell. Single-crystal X-ray diffraction refinements converged to a model of composition Bi6(Bi0.32Fe0.68)(PO4)4O4 (hexabismuth iron tetraphosphate tetraoxide), in which Bi and Fe are displaced from the origin giving rise to a random distribution over the 2i sites instead of 1a, the origin of space group P1. The isotropic displacement parameter for Bi/Fe has a reasonable value in this model. This structure establishes for the first time that Fe substitutes in the Bi-deficient site in this series of materials and that Fe and Bi are disordered around the center of symmetry. These results enhance understanding of the crystal chemistry of these main group phosphates that are of interest in ion transport.Chemical Engineerin
Layered ternary transition metal nitrides; synthesis, structure and physical properties
Two-dimensional structures are an emerging class of materials within nitride chemistry. We report here our systematic studies of two groups of these layered compounds: 1 Lithium transition metal compounds, Li3-x-y□yMxN (M = Co, Ni, Cu, □ = Li vacancy) and 2 ternary transition metal nitrides of general formulation AMN2 (A = alkaline earth metal, M = Ti, Zr, Hf). Compounds in class 1 are based on the hexagonal Li3N structure, unique to nitrides. Compounds in group 2, by contrast, crystallise with oxide structures (α-NaFeO2 or KCoO2). Specific and unusual synthetic methods have been developed to reproducibly prepare these compounds. Compounds in series 1 contain ordered or disordered Li vacancies at increased levels relative to the parent Li3N, itself a Li+ fast ion conductor. Nitrides in series 2 should be nominally diamagnetic (S = 0), yet magnetic measurements reveal behaviour seemingly inconsistent with this assumption. © 2001 Elsevier Science B.V
ISOLATION FROM ALEXA-LEIOPETALA AND X-RAY CRYSTAL-STRUCTURE OF ALEXINE, (1R,2R,3R,7S,8S)-3-HYDROXYMETHYL-1,2,7-TRIHYDROXYPYRROLIZIDINE [(2R,3R,4R,5S,6S)-2-HYDROXYMETHYL-1-AZABICYCLO[3.3.0]OCTAN-3,4,6-TRIOL], A UNIQUE PYRROLIZIDINE ALKALOID
The isolation from Alexa leiopetala and identification by X-ray crystal structure analysis of (1R,2R,3R,7S,8S)-3-hydroxymethyl-1,2,7-trihydroxypyrrolizidine [(2R,3R,4R,5S,6S)-2-hydroxymethyl-1-azabicyclo[3.3.0]octan-3,4,6-triol], a unique pyrrolizidine alkaloid, is described. A preliminary study of the inhibition of glycosidases by alexine is reported. © 1988
The syntheses of high oxidation state metal complexes containing the tripodal ligand [(*5-C5H5)Co{P(OMe)2(=O)}3]- and the X-ray crystal structure of [(*5-C5H5)Co{P(OMe)2(=O)}3ReO3]
Effects of reduced oxygen level on the mortality and hatching rate of Chondrostoma nasus embryos
Crystal and molecular structure of decahydroquinoline hydrobromide, and its relation to piperidine hydrobromide
Biochemical changes during embryogenesis of the Pacific halibut, Hippoglossus stenolepis (Schmidt)
Temperature and oxygen tension influence the development of muscle cellularity in embryonic rainbow trout
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