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The purpose of the first investigation was to determine the feasibility of developing a method to predict, with an accuracy of better than plus or minus 1%, the maximum power which can be produced by a helicopter gas turbine engine at full-power conditions. The prediction was to be made using information obtained from the engine while the engine was operated prior to lift-off at a partial-power condition of no more than 30% of normal rated power. The prediction method was to be capable of identifying the changes in maximum engine power available due to all possible types of engine deterioration and all ambient conditions. This is a follow-on program to determine the effects of higher power levels, a continuous update system, and improved sensor accuracies on the possible improvement of MPA prediction accuracy.

Background Pre-exposure prophylaxis (PrEP) has proven biological efficacy to reduce the sexual acquisition of the human immunodeficiency virus (HIV). The PROUD study found that PrEP conferred higher protection than in placebo-controlled trials, reducing HIV incidence by 86 % in a population with seven-fold higher HIV incidence than expected. We present the baseline characteristics of the PROUD study population and place the findings in the context of national sexual health clinic data. Methods The PROUD study was designed to explore the real-world effectiveness of PrEP (tenofovir-emtricitabine) by randomising HIV-negative gay and other men who have sex with men (GMSM) to receive open-label PrEP immediately or after a deferral period of 12 months. At enrolment, participants self-completed two baseline questionnaires collecting information on demographics, sexual behaviour and lifestyle in the last 30 and 90 days. These data were compared to data from HIV-negative GMSM attending sexual health clinics in 2013, collated by Public Health England using the genitourinary medicine clinic activity database (GUMCAD). Results The median age of participants was 35 (IQR: 29–43). Typically participants were white (81 %), educated at a university level (61 %) and in full-time employment (72 %). Of all participants, 217 (40 %) were born outside the UK. A sexually transmitted infection (STI) was reported to have been diagnosed in the previous 12 months in 330/515 (64 %) and 473/544 (87 %) participants reported ever having being diagnosed with an STI. At enrolment, 47/280 (17 %) participants were diagnosed with an STI. Participants reported a median (IQR) of 10 (5–20) partners in the last 90 days, a median (IQR) of 2 (1–5) were condomless sex acts where the participant was receptive and 2 (1–6) were condomless where the participant was insertive. Post-exposure prophylaxis had been prescribed to 184 (34 %) participants in the past 12 months. The number of STI diagnoses was high compared to those reported in GUMCAD attendees. Conclusions The PROUD study population are at substantially higher risk of acquiring HIV infection sexually than the overall population of GMSM attending sexual health clinics in England. These findings contribute to explaining the extraordinary HIV incidence rate during follow-up and demonstrate that, despite broad eligibility criteria, the population interested in PrEP was highly selective. Trial registration Current Controlled TrialsISRCTN94465371. Date of registration: 28 February 2013. Electronic supplementary material The online version of this article (doi:10.1186/s13063-016-1286-4) contains supplementary material, which is available to authorized users.

Authored by Nigel Biggar, Longman and Todd: Published by Darton, 2004, £10.95 (paper back), pp 220. ISBN 0-232-52406-8 The literature on euthanasia and suicide is substantial and ever growing. In his book Aiming to kill , Nigel Biggar, a theologian, adds to this something that is hard to come across, in a concise but comprehensive form. His book explores the theological basis of the sanctity of life doctrine: rather than merely asserting what the doctrine demands, simply citing as authority that it is a traditional and fundamental principle, he offers an account of its historical and modern-day rationale. The book is divided into four unequal parts, whose quality varies. These chapters are designed to provide: firstly, the appropriate sociolegal and ethical context; secondly, an overview and analysis of arguments relating to the value of life; thirdly, an overview and analysis of arguments on the morality of killing; and finally, a section drawn from the conclusions of previous chapters and expounding the threat of the “slippery slope”. Biggar does not claim to come into the debate without …

The four separated isomers of the muscarinic agonist 1, previously known as AF30, have been synthesized by a route that has allowed the absolute stereochemistry of each isomer to be assigned. With the chirality of (-)-camphanic acid known, X-ray analysis of the more crystalline intermediate diastereomeric camphanate 5A allowed the absolute stereochemistry at the quinuclidine chiral center to be determined. Each diastereomer was separately transformed into the spirodioxolane with concomitant introduction of the second chiral center. Chromatographic separation followed by a second crystal structure determination revealed the absolute stereochemistry of all four isomers of 1. Detailed biological evaluation of each isomer indicated that while the 3(R),2'(S) isomer was the most active in binding studies, it was the 3(R),2'(R) isomer that displayed the largest functional selectivity between ganglion (M-1 site) and heart (M-2 site). With the same internal chiral standard, the absolute configuration of the more active enantiomer of 3 was shown to be S, confirming earlier literature reports.

Preparation des composes du titre par alkylation puis decarboxylation des oxo-2 cyclopentane ou cyclohexane carboxylates de t-butyle

1-Benzyl-2-methyl-4,5-dihydrpimidazole has been lithiated and C-acylated by reaction with esters and a nitrile. The products do not exist as 2-(2-oxoalkyl)dihydroimidazoles but as the alternative tautomers, as indicated by spectroscopic and crystallographic data.

2-Alkyl-1-benzyl-3-methyl-2-imidazolinium salts with Grignard reagents give addition products that are hydrolysed to ketone; 2-imidazolines and 2-imidazolinium salts with hydride reagents afford N-alkylated 1,2-diaminoethanes.

The methyl ester functionality in arecoline and related esters has been replaced by 1,2,4-oxadiazole to generate the most potent and efficacious muscarinic agonists known.

Mail-survey response rates and their prediction are important issues for researchers. The conceptual differences between industrial and most non-industrial populations raised doubt about the applicability of the Heberlein and Baumgartner model for the prediction of industrial mail-survey response rates. A test of their model using data from industrial mail-survey studies revealed a low level of predictive ability. A new model, based upon a linear logit specification and data from industrial populations, was developed and validated using a hold-out sample. The results suggested that the model based upon the new specification was superior to the simple linear alternative. The model identified a number of variables which were associated with response rates from industrial populations, and allows researchers to test and refine alternative survey designs.

Keto alkyne cyclisation has been used to prepare tetrahydrobenzo [b] furans (4) and (15) but cyclopenta[b]furans are not available by this procedure. Compound (15) has been converted into benzofuran prostacyclin analogues (5) and (6) by extremely short routes. Conditions are also described for the conversion of the same keto alkynes into tetrahydrobenzo[b]- and cyclopenta[b]- thiophenes and -pyrroles, (7a,b) and (9a,b). Syntheses of thiophene prostacyclin analogues (8a) and (8b) are also discussed.

Uroporphyrin-III (4) has been synthesised by a route which allows [2,11-13C2]porphobilinogen (3) to be elaborated to give [10,14-13C2]uroporphyrin-III (4). This, after reduction to the corresponding porphyrinogen, has been transformed enzymically into [10,14-13C2]protoporphyrin-IX (2). The 13C n.m.r. signal from position 10 (β-meso-carbon) of the methyl esters of both porphyrins (2) and (4) appears as a 5.5 Hz doublet. This demonstration of long-range coupling is of decisive importance for related research on the nature of the rearrangement process by which the natural type III porphyrins are biosynthesised.A new procedure has been developed for pyrromethane formation, based on catalysis by tin(IV) chloride, which appears to be of general value.

Photochemically induced addition of methanol to pyran-3-uloses affords a ready method of extending the pyranose ring at C-1.

1-Benzyl-2-alkyl-3-methyl-4,5-dihydroimidazolium salts with Grignard reagents give addition products that are hydrolysed to ketones; 4,5-dihydroimidazoles and 4,5-dihydroimidazolium salts with hydride reagents afford N-alkylated ethane-1,2-diamines.

In the analytical method outlined in this paper airborne methyl tert-butyl ether (MTBE) and other hydrocarbon vapours are sampled by drawing the atmosphere through a primary sorption tube containing a porous polymer sorbent. A known volume of air is drawn by a suitable sampling pump, which may be worn by an operator or remain static at a specified location. Factors influencing the choice of sorbent are discussed. After sampling, the primary sorption tube is capped and returned to the laboratory for analysis. Sampled vapours are desorbed from the primary trap by thermal desorption. The desorbed sample is re-concentrated on a small secondary cold trap containing a solid sorbent. When desorption from the primary trap is complete, the secondary trap is heated rapidly and the sample (now in a very narrow plug) is swept on to a fused-silica capillary column that is located only a few millimetres from the sorbent bed of the secondary trap. MTBE is separated from gasoline hydrocarbons on an OV-1701 capillary column and quantified by a calibrated flame-ionisation detector.

[β-13C]-, [γ-13C]-, and [δ-13C]-Protoporphyrin-IX dimethyl esters have been synthesised by unambiguous routes from [13C]formaldehyde to allow assignment of the four n.m.r. 13C-signals from the meso-carbons; the dimethyl ester of diacetyldeuteroporphyrin-IX has been similarly studied.

Addition of the europium complex of 3-heptafluorobutanoyl-(+)-camphor to racemates of alcohols, sulphoxides, an epoxide, and an aldehyde causes separation of n.m.r. signals of the enantioners.