Scope of the direct trimerisation to C3-symmetric cyclotribenzylene derivatives

The scope of the trimerisation reaction of 3-substituted benzyl alcohols was explored. Several C 3 -symmetric cyclotribenzylene derivatives were obtained in preparative useful yields in one step and applied to the short synthesis (one or two steps) of two CTB derivatives, so far only accessible in six or seven linear steps

Search for a bound di-neutron by comparing 3^3He(e,e'p)d and 3^3H(e,e'p)X measurements

We report on a search for a bound di-neutron by comparing electron-induced proton-knockout $(e,e'p)$ measurements from Helium-3 ($^3$He) and Tritium ($^3$H). The measurements were performed at Jefferson Lab Hall A with a 4.326 GeV electron beam, and kinematics of large momentum transfer $Q^2 \approx 1.9$ (GeV/$c$)$^2$ and $x_B>1$, to minimize contributions from non quasi-elastic (QE) reaction mechanisms. Analyzing the measured $^3$He missing mass ($M_{miss}$) and missing energy ($E_{miss}$) distributions, we can distinguish the two-body break-up reaction, in which the residual proton-neutron system remains bound as a deuteron. In the $^3$H mirror case, under the exact same kinematic conditions, we do not identify a signature for a bound di-neutron with similar binding energy to that of the deuteron. We calculate exclusion limits as a function of the di-neutron binding energy and find that, for binding equivalent to the deuteron, the two-body break-up cross section on $^3$H is less than 0.9% of that on $^3$He in the measured kinematics at the 95% confidence level.Comment: 6 pages, 3 figure

On ordinal utility, cardinal utility, and random utility

Though the Random Utility Model (RUM) was conceived  entirely in terms of ordinal utility, the apparatus throughwhich it is widely practised exhibits properties of  cardinal utility.  The adoption of cardinal utility as a  working operation of ordinal is perfectly valid, provided  interpretations drawn from that operation remain faithful  to ordinal utility.  The paper considers whether the latterrequirement holds true for several measurements commonly  derived from RUM.  In particular it is found that  measurements of consumer surplus change may depart from  ordinal utility, and exploit the cardinality inherent in  the practical apparatus.

Accessibility appraisal of integrated land-use-transport strategies: methodology and case study for the Netherlands Randstad area

Conventional approaches to measuring accessibility benefits are not capable of fully measuring the total accessibility benefits of integrated land-use-transport strategies, in which both land-use and transport changes form part of the policy strategy. In this paper a comprehensive methodology for analysing accessibility impacts and accessibility benefits, which is based on location-based and utility-based accessibility measures within an integrated land-use-transport interaction modelling framework, is described and applied in a case study. The case study examines the accessibility benefits and related user benefits of intensive mixed-use strategies aimed at increasing the density and diversity of activities around railway stations for the Randstad area of the Netherlands for the 1996-2030 period. A heavy concentration of activities near railway stations is shown to result in decreasing marginal returns for public-transport users and disbenefits for car users. © 2006 a Pion publication printed in Great Britain

Safe working in a 7-day service. Experience of hip fracture care as documented by the UK National Hip Fracture Database.

to describe differences in care and 30-day mortality of patients admitted with hip fracture on weekends (Saturday-Sunday) compared to weekdays (Monday-Friday), and their relationship to the organisation of care. data came from the National Hip Fracture Database (NHFD) linked to ONS mortality data on 52,599 patients presenting to 162 units in England between 1 January and 31 December 2014. This was combined with information on geriatrician staffing and major trauma centre (MTC) status. 30-day mortality and care were compared for patients admitted at weekends and weekdays; separately for patients treated in units grouped by the mean level of input by geriatricians, weekend geriatrician clinical cover and MTC status. Differences were adjusted for variation in patients' characteristics. there was no evidence of differences in 30-day mortality between patients admitted at weekends compared to weekdays (7.2 vs 7.5%, P = 0.3) before or after adjusting for patient characteristics in either MTCs or general hospitals. The proportion receiving a preoperative geriatrician assessment was lower at weekends (42.8 vs 60.7%, P < 0.001). 30-day mortality was lower in units with higher levels of geriatrician input, but there was no weekend mortality effect associated with lower levels of input or absence of weekend cover. there was no evidence of a weekend mortality effect among patients treated for hip fracture in the English NHS. It appears that clinical teams provide comparably safe and effective care throughout the week. However, greater geriatrician involvement in teams was associated with overall lower mortality