Neutral thioether and selenoether macrocyclic coordination to Group 1 cations (Li–Cs) – synthesis, spectroscopic and structural properties

The complexes [M(L)][BArF] (BArF = tetrakis{3,5-bis(trifluoromethyl)-phenyl}borate), L = [18]aneO4S2 (1,4,10,13-tetraoxa-7,16-dithiacyclooctadecane): M = Li–Cs; L = [18]aneO2S4 (1,10-dioxa-4,7,13,16-tetrathiacyclooctadecane): M = Li, Na, K; L = [18]aneO4Se2 (1,4,10,13-tetraoxa-7,16-diselenacyclooctadecane): M = Na, K, as well as [Na(18-crown-6)][BArF], are obtained in good yield as crystalline solids by reaction of M[BArF] with the appropriate macrocycle in dry CH2Cl2. X-ray crystallographic analyses of [Li([18]aneO4S2)][BArF] and [Li([18]aneO2S4)][BArF] show discrete distorted octahedral cations with hexadentate coordination to the macrocycle. The heavier alkali metal complexes all contain hexadentate coordination of the heterocrown, supplemented by M?F interactions via the anions, producing extended structures with higher coordination numbers; Na: CN = 7 or 8; K: CN = 8; Rb: CN = 9; Cs: CN = 8 or 10. Notably, all of the structures exhibit significant M–S/Se coordination. The crystal structures of the potassium and rubidium complexes show two distinct [M(heterocrown)]+ cations, one with M?F interactions to two mutually cis [BArF]? anions, and the other with mutually trans [BArF]? anions, giving 1D chain polymers. Solution multinuclear (1H, 13C, 7Li, 23Na, 133Cs) NMR data show that the macrocyclic coordination is retained in CH2Cl2 solution

House of Commons Science and Technology Select Committee Session 2012-13, Forensic Science, Minutes of Evidence HC 930-ii, Oral Evidence, 6th February 2013

House of Commons Science and Technology Select Committee Session 2012-13, Forensic Science, Minutes of Evidence HC 930-ii, Oral Evidence, 6th February 201

Water surface height determination with a GPS wave glider: a demonstration in Loch Ness, Scotland

A geodetic GPS receiver has been installed on a Wave Glider, an unmanned water surface vehicle. Using kinematic precise point positioning (PPP) GPS, which operates globally without directly requiring reference stations, surface heights are measured with ~0.05-m precision. The GPS Wave Glider was tested in Loch Ness, Scotland, by measuring the gradient of the loch’s surface height. The experiment took place under mild weather, with virtually no wind setup along the loch and a wave field made mostly of ripples and wavelets. Under these conditions, the loch’s surface height gradient should be approximately equal to the geoid slope. The PPP surface height gradient and that of the Earth Gravitational Model 2008 geoid heights do indeed agree on average along the loch (0.03 m km−1). Also detected are 1) ~0.05-m-sized height changes due to daily water pumping for hydroelectricity generation and 2) high-frequency (0.25–0.5 Hz) oscillations caused by surface waves. The PPP heights compare favorably (~0.02-m standard deviation) with relative carrier phase–based GPS processing. This suggests that GPS Wave Gliders have the potential to autonomously determine centimeter-precise water surface heights globally for lake modeling, and also for applications such as ocean modeling and geoid/mean dynamic topography determination, at least for benign surface states such as those encountered during the reported experiment

Theory of linear sweep voltammetry with diffuse charge: Unsupported electrolytes, thin films, and leaky membranes

Linear sweep and cyclic voltammetry techniques are important tools for electrochemists and have a variety of applications in engineering. Voltammetry has classically been treated with the Randles-Sevcik equation, which assumes an electroneutral supported electrolyte. In this paper, we provide a comprehensive mathematical theory of voltammetry in electrochemical cells with unsupported electrolytes and for other situations where diffuse charge effects play a role, and present analytical and simulated solutions of the time-dependent Poisson-Nernst-Planck equations with generalized Frumkin-Butler-Volmer boundary conditions for a 1:1 electrolyte and a simple reaction. Using these solutions, we construct theoretical and simulated current-voltage curves for liquid and solid thin films, membranes with fixed background charge, and cells with blocking electrodes. The full range of dimensionless parameters is considered, including the dimensionless Debye screening length (scaled to the electrode separation), Damkohler number (ratio of characteristic diffusion and reaction times), and dimensionless sweep rate (scaled to the thermal voltage per diffusion time). The analysis focuses on the coupling of Faradaic reactions and diffuse charge dynamics, although capacitive charging of the electrical double layers is also studied, for early time transients at reactive electrodes and for nonreactive blocking electrodes. Our work highlights cases where diffuse charge effects are important in the context of voltammetry, and illustrates which regimes can be approximated using simple analytical expressions and which require more careful consideration

Room with a VDU: The Development of the ‘Glass House’ in the Corporate Workplace

Abstract This article argues that the presentation of early computer technology and its reception by the public had a causal effect on the design of computer products. It is also argued that the desire to show computers in operation led to the emergence and proliferation of the ‘glass house’, a particular element of the commercial interior landscape of the 1960s and 1970s. These glass-walled secure areas, built to house mainframe computer installations, appeared in order to meet the conflicting requirements of environmental stability, controlled access and crucially, the conspicuous display of corporate status. Although the phenomenon of the glass house disappeared as the computers they housed developed from large, centralised systems into distributed networks of stand-alone computers, this article posits that the widespread adoption of the glass house not only had a profound effect on the visual design of computers themselves but also led to the growth of a range of subsidiary industries, as well as having a lasting impact on the perception and reception of computers in the workplace and attitudes towards the specialist staff involved in their maintenance. Keywords: glass house, computers, technology, workplace, display, IB

The effect of active toe movement (AToM) on calf pump function and deep vein thrombosis in patients with acute foot and ankle trauma treated with cast - a prospective randomized study

Background Patients with foot and ankle trauma treated with cast are advised to perform toe movements to prevent venous thromboembolism (VTE). Our aim was to determine the effect of active toe movement on asymptomatic deep vein thrombosis (DVT) and venous calf pump function. Methods Patients aged 18–60 years with acute foot and ankle trauma requiring below knee non weight bearing cast were randomized to intervention (regular active toe movement) or control groups (n = 100). Patients had bilateral lower limb venous ultrasound to assess for DVT on discharge from clinic. Patients requiring chemical thromboprophylaxis were excluded. Results 78 completed the study. 27% sustained asymptomatic DVT, with no statistically significant difference in calf pump function or DVT incidence between groups. All DVT's occurred in the injured lower limb. Conclusion Active toe movement is not a viable strategy for thromboprophylaxis in patients with acute foot and ankle trauma treated with cast

The argument of the broken pane: Suffragette consumerism and newspapers

Within the cut-throat world of newspaper advertising the newspapers of Britain's Women's Social and Political Union (WSPU) Votes for Women and the Suffragette managed to achieve a balance that has often proved to be an impossible challenge for social movement press—namely the maintenance of a highly political stance whilst simultaneously exploiting the market system with advertising and merchandising. When the militant papers advocated window smashing of West End stores in 1912–1913, the companies who were the target still took advertisements. Why? What was the relationship between news values, militant violence and advertising income? ‘Do-it-yourself’ journalism operated within a context of ethical consumerism and promotionally orientated militancy. This resulted in newspaper connections between politics, commerce and a distinct market profile, evident in the customisation of advertising, retailer dialogue with militants and longer-term loyalty—symptomatic of a wider trend towards newspaper commercialism during this period

RTOG 0518: Randomized Phase III Trial to Evaluate Zoledronic Acid for Prevention of Osteoporosis and Associated Fractures in Prostate Cancer Patients

Background: RTOG 0518 evaluated the potential benefit of zoledronic acid therapy in preventing bone fractures for patients with high grade and/or locally advanced, non-metastatic prostate adenocarcinoma receiving luteinizing hormone-releasing hormone (LHRH) agonist and radiotherapy (RT). Methods: Eligible patients with T-scores of the hip ( −2.5 vs. > −1.0) and negative bone scans were prospectively randomized to either zoledronic acid, 4 mg, concurrently with the start of RT and then every six months for a total of 6 infusions (Arm 1) or observation (Arm 2). Vitamin D and calcium supplements were given to all patients. Secondary objectives included quality of life (QOL) and bone mineral density (BMD) changes over a period of three years. Results: Of 109 patients accrued before early closure, 96 were eligible. Median follow-up was 36.3 months for Arm I and 34.8 months for Arm 2. Only two patients experienced a bone fracture (1 in each arm) resulting in no difference in freedom from any bone fracture (p=0.95), nor in QOL. BMD percent changes from baseline to 36 months were statistically improved with the use of zoledronic acid compared to observation for the lumbar spine (6% vs. −5%, p<0.0001), left total hip (1% vs. −8%, p=0.0002), and left femoral neck (3% vs. −8%, p=0.0007). Conclusions: For patients with advanced, non-metastatic prostate cancer receiving LHRH agonist and RT, the use of zoledronic acid was associated with statistically improved BMD percent changes. The small number of accrued patients resulted in decreased statistical power to detect any differences in the incidence of bone fractures or QOL