Some silyl anions

Two attempts to módify the ammonium salts of silyl thiol and silyl selenol were made in an effort to make them easily soluble. Both attempts were unsuccessful. The first was to try to form the potassium salt by using an ion exchange resin; the second was to prepare the methylsilyl derivative in the hope that it would be soluble. The ammonium salt of silyl tellurol was also prepared by an analogous route to the sulphur and selenium compounds.2H₂Te + (SiH₃)₃N → NH₄TeSiH₃ + (SiH3)₃Te ¹.Methyl silyl telluride was prepared from it by adding methyl iodide.CH₃I + NH₄ TeSiH₃ → CH₃TeSiH₃ + NH₄ I ².Lithium silyl oxide, sulphide and selenide was prepared by the reaction of methyl lithium, as a solution in diethyl ether at -64°, with disiloxane, disilyl sulphide and disilyl selenide.CH₃Li + (SiH₃)₂Y → LiYSiH₃ + CH₃SiH₃ ³.Y = (0, S, Se)Similar reactions were carried out with methyl lithium and trisilyl phosphine and trisilyl arsine.CH₃Li + (SiH₃)₃Z→LiZ(SiH₃)₂ + CH₃SiH₃'⁴Z= (P, As)Yields of the lithium derivatives were all of the order of 80% and they were characterised by i.r., raman and n.m.r. spectroscopy. In some cases a reaction with trimethylsilyl chloride was also carried out.Reactions of these compounds, as a solution in diethyl ether, were carried out with a variety of reagents but most were unsuccessful in that the desired products were not isolated. Instead, the main volatile silyl product was generally (SiH₃)₃Z or (SiH₃)₂Y. This was attributed to the side-reactions:SiH₃ - Y - Q +Bθ → SiH₃B + θY - Q ⁵.and (SiH₃)₂Z - Q + Bθ → SiH₃B + SiH₃QZθ ⁶.where Q is any group of interestand Bθ is a base - in this case YSiH₃ or Z(SiH₃)₂This conclusion was confirmed by reactions of the silyl anions and closely related molecules producing exchange situations. Attempts to limit the extent of reactions (5) and (6) consisted of the use of benzene as a solvent, the use of trimethylamine and the absence of solvent. The first two were unsuccessful but the latter worked. It was possible to prepare disilyl phosphine and 1,1,1-trimethyl disiloxane by this method.2LiP(SiH₃)₂ + H₂S -- HP(SiH₃)₂ + Li₂S ⁷.Li0SiH₃ + (CH₃)₃SiCl → (CH₃)₃0SiH₃ + LiCl ⁸

Influence of springtime phenology on the ratio of soil respiration to total ecosystem respiration in a mixed temperate forest

Total ecosystem (Reco) and soil (Rs) respiration are important CO2 fluxes in the carbon balance of forests. Typically Rs accounts for between 30-80% of Reco, although variation in this ratio has been shown to occur, particularly at seasonal time scales. The objective of this study was to relate changes in Rs/Reco ratio to changing springtime phenological conditions in forest ecosystems. We used one year (2003) of automated and twelve years (1995-2006) of manual chamber-based measurements of Rs. Reco was determined using tower-based eddy covariance measurements for an oak-dominated mixed temperate forest at Harvard Forest, Petersham, MA, USA. Phenological data were obtained from field observations and the JRC fAPAR remote sensing product. The automated and eddy covariance data showed that springtime phenological events do influence the ratio of soil to total ecosystem respiration. During canopy development, Reco rose strongly, mainly the aboveground component, due to the formation of an increasing amount of respiring leaf tissue. An increase in Rs was observed after most of the canopy development, which is probably the consequence of a shift in allocation of photosynthate products from above- to belowground. This hypothesized allocation shift was also confirmed by the results of the twelve year manual chamber-based measurements

Persistent elastic behavior above a megathrust rupture patch: Nias island, West Sumatra

We quantify fore-arc deformation using fossil reefs to test the assumption commonly made in seismic cycle models that anelastic deformation of the fore arc is negligible. Elevated coral microatolls, paleoreef flats, and chenier plains show that the Sumatran outer arc island of Nias has experienced a complex pattern of relatively slow long-term uplift and subsidence during the Holocene epoch. This same island rose up to 2.9 m during the Mw 8.7 Sunda megathrust rupture in 2005. The mismatch between the 2005 and Holocene uplift patterns, along with the overall low rates of Holocene deformation, reflects the dominance of elastic strain accumulation and release along this section of the Sunda outer arc high and the relatively subordinate role of upper plate deformation in accommodating long-term plate convergence. The fraction of 2005 uplift that will be retained permanently is generally <4% for sites that experienced more than 0.25 m of coseismic uplift. Average uplift rates since the mid-Holocene range from 1.5 to −0.2 mm/a and are highest on the eastern coast of Nias, where coseismic uplift was nearly zero in 2005. The pattern of long-term uplift and subsidence is consistent with slow deformation of Nias along closely spaced folds in the north and trenchward dipping back thrusts in the southeast. Low Holocene tectonic uplift rates provide for excellent geomorphic and stratigraphic preservation of the mid-Holocene relative sea level high, which was under way by ∼7.3 ka and persisted until ∼2 ka

Effect of a reduction in glomerular filtration rate after nephrectomy on arterial stiffness and central hemodynamics: rationale and design of the EARNEST study

Background: There is strong evidence of an association between chronic kidney disease (CKD) and cardiovascular disease. To date, however, proof that a reduction in glomerular filtration rate (GFR) is a causative factor in cardiovascular disease is lacking. Kidney donors comprise a highly screened population without risk factors such as diabetes and inflammation, which invariably confound the association between CKD and cardiovascular disease. There is strong evidence that increased arterial stiffness and left ventricular hypertrophy and fibrosis, rather than atherosclerotic disease, mediate the adverse cardiovascular effects of CKD. The expanding practice of live kidney donation provides a unique opportunity to study the cardiovascular effects of an isolated reduction in GFR in a prospective fashion. At the same time, the proposed study will address ongoing safety concerns that persist because most longitudinal outcome studies have been undertaken at single centers and compared donor cohorts with an inappropriately selected control group.&lt;p&gt;&lt;/p&gt; Hypotheses: The reduction in GFR accompanying uninephrectomy causes (1) a pressure-independent increase in aortic stiffness (aortic pulse wave velocity) and (2) an increase in peripheral and central blood pressure.&lt;p&gt;&lt;/p&gt; Methods: This is a prospective, multicenter, longitudinal, parallel group study of 440 living kidney donors and 440 healthy controls. All controls will be eligible for living kidney donation using current UK transplant criteria. Investigations will be performed at baseline and repeated at 12 months in the first instance. These include measurement of arterial stiffness using applanation tonometry to determine pulse wave velocity and pulse wave analysis, office blood pressure, 24-hour ambulatory blood pressure monitoring, and a series of biomarkers for cardiovascular and bone mineral disease.&lt;p&gt;&lt;/p&gt; Conclusions: These data will prove valuable by characterizing the direction of causality between cardiovascular and renal disease. This should help inform whether targeting reduced GFR alongside more traditional cardiovascular risk factors is warranted. In addition, this study will contribute important safety data on living kidney donors by providing a longitudinal assessment of well-validated surrogate markers of cardiovascular disease, namely, blood pressure and arterial stiffness. If any adverse effects are detected, these may be potentially reversed with the early introduction of targeted therapy. This should ensure that kidney donors do not come to long-term harm and thereby preserve the ongoing expansion of the living donor transplant program.&lt;p&gt;&lt;/p&gt

Report of Seminar on Law and Medicine

Reports from the UK/CLE Seminar on Law and Medicine held May 26-28, 1976

The association between symptomatic, severe hypoglycaemia and mortality in type 2 diabetes: retrospective epidemiological analysis of the ACCORD study

Objective To determine whether there is a link between hypoglycaemia and mortality among participants in the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial

Capabilities, Performance, and Status of the SOFIA Science Instrument Suite

The Stratospheric Observatory for Infrared Astronomy (SOFIA) is an airborne observatory, carrying a 2.5 m telescope onboard a heavily modified Boeing 747SP aircraft. SOFIA is optimized for operation at infrared wavelengths, much of which is obscured for ground-based observatories by atmospheric water vapor. The SOFIA science instrument complement consists of seven instruments: FORCAST (Faint Object InfraRed CAmera for the SOFIA Telescope), GREAT (German Receiver for Astronomy at Terahertz Frequencies), HIPO (High-speed Imaging Photometer for Occultations), FLITECAM (First Light Infrared Test Experiment CAMera), FIFI-LS (Far-Infrared Field-Imaging Line Spectrometer), EXES (Echelon-Cross-Echelle Spectrograph), and HAWC (High-resolution Airborne Wideband Camera). FORCAST is a 540 m imager with grism spectroscopy, developed at Cornell University. GREAT is a heterodyne spectrometer providing high-resolution spectroscopy in several bands from 60240 m, developed at the Max Planck Institute for Radio Astronomy. HIPO is a 0.31.1 m imager, developed at Lowell Observatory. FLITECAM is a 15 m wide-field imager with grism spectroscopy, developed at UCLA. FIFI-LS is a 42210 m integral field imaging grating spectrometer, developed at the University of Stuttgart. EXES is a 528 m high-resolution spectrograph, developed at UC Davis and NASA ARC. HAWC is a 50240 m imager, developed at the University of Chicago, and undergoing an upgrade at JPL to add polarimetry capability and substantially larger GSFC detectors. We describe the capabilities, performance, and status of each instrument, highlighting science results obtained using FORCAST, GREAT, and HIPO during SOFIA Early Science observations conducted in 2011

Assembly and characterisation of a unique onion diversity set identifies resistance to Fusarium basal rot and improved seedling vigour

Conserving biodiversity is critical for safeguarding future crop production. Onion (Allium cepa L.) is a globally important crop with a very large (16 Gb per 1C) genome which has not been sequenced. While onions are self-fertile, they suffer from severe inbreeding depression and as such are highly heterozygous as a result of out-crossing. Bulb formation is driven by daylength, and accessions are adapted to the local photoperiod. Onion seed is often directly sown in the field, and hence seedling establishment is a critical trait for production. Furthermore, onion yield losses regularly occur worldwide due to Fusarium basal rot caused by Fusarium oxysporum f. sp. cepae. A globally relevant onion diversity set, consisting of 10 half-sib families for each of 95 accessions, was assembled and genotyping carried out using 892 SNP markers. A moderate level of heterozygosity (30–35%) was observed, reflecting the outbreeding nature of the crop. Using inferred phylogenies, population structure and principal component analyses, most accessions grouped according to local daylength. A high level of intra-accession diversity was observed, but this was less than inter-accession diversity. Accessions with strong basal rot resistance and increased seedling vigour were identified along with associated markers, confirming the utility of the diversity set for discovering beneficial traits. The onion diversity set and associated trait data therefore provide a valuable resource for future germplasm selection and onion breeding

A useful savagery: The invention of violence in nineteenth-century England

‘A Useful Savagery: The Invention of Violence in Nineteenth-Century England’ considers a particular configuration of attitudes toward violence that emerged in the early decades of the nineteenth century. As part of a longer-term process of emerging ‘sensibilities,’ violence was, seemingly paradoxically, ‘invented’ as a social issue while concurrently relocated in the ‘civilised’ imagination as an anti-social feature mainly of ‘savage’ working-class life. The dominant way this discourse evolved was through the creation of a narrative that defined ‘civilisation’ in opposition to the presumed ‘savagery’ of the working classes. Although the refined classes were often distanced from the physical experience of violence, concern with violence and brutality became significant parts of social commentary aimed at a middle-class readership. While stridently redefining themselves in opposition to ‘brutality,’ one of the purposes of this literature was to create a new middle class and justify the expansion of state power. By the closing decades of the nineteenth century, as the working classes adopted tenets of Victorian respectability, a proliferating number of social and psychological ‘others’ were identified against which ‘civilised’ thought could define itself