Flight and wind-tunnel comparisons of the inlet-airframe interaction of the F-15 airplane

The design of inlets and nozzles and their interactions with the airplane which may account for a large percentage of the total drag of modern high performance aircraft is discussed. The inlet/airframe interactions program and the flight tests conducted is described. Inlet drag and lift data from a 7.5% wind-tunnel model are compared with data from an F-15 airplane with instrumentation to match the model. Pressure coefficient variations with variable cowl angles, capture ratios, examples of flow interactions and angles of attack are for Mach numbers of 0.6, 0.9, 1.2, and 1.5 are presented

Multivariate Time Series Approaches To Analysing The Northern Irish Conflict: Lessons For Future Sub-State Conflict Control

This paper is essentially an introduction to the use of multivariate time series analyses of the Northern Irish conflict from 1969-1981.It draws on the conceptual work of Paul Smoker to describe systemic conflict relationships between all the parties to this conflict. Using some of the most comprehensive statistical documentation ever compiled on an internal conflict, the authors present an innovative methodology to show the highly structured nature of this conflict over a long period of time. The paper and its ancillary web sites present not only the data archive, but also the univariate, bivariate and multivariate time series programmes used to make the analyses. The outputs are presented in the form of descriptions of associated influence or ‘systemograms’ which can describe the dynamic and changing conflict ecology where apparently disparate conflict behaviour such as house searches, plastic bullet firings and the killing of military personnel, are highly correlated. Measures of autocorrelation are used to suggest a loss of freedom in the actions of particular conflict participants. Particular attention is given to the use of “less-lethal weapons” and their impact on overall conflict dynamics. What emerges is that sectarian killings form a distinct conflict susbset, whereas the counter-insurgency behaviour of the state security forces act as a conflict driver, ratchet ting up the conflict as each more severe phase of the counterinsurgency programme is introduced. The paper attempts to introduce a whole systems conflict approach which is both dynamic and puzzling, since in many respects it indicates cooperation between the various participants to carry on the conflict at a systemic level. The provisional lessons of this study are that sub-state conflict control measures can prove dysfunctional. The work is very much a case of research in progress and the findings remain tentative. We are re-introducing it at this time since it does open the prospect of repeating the research methodology in other sub-state conflicts such as Israel and Iraq, if reliable data were ever to become available

Pregnancy related risk perception in pregnant women, midwives & doctors: a cross-sectional survey

Background: Risk perception in relation to pregnancy and birth is a complex process influenced by multiple personal, psychological and societal factors. Traditionally, the risk perception of healthcare professionals has been presented as more objective and authoritative than that of pregnant women. Doctors have been presented as more concerned with biomedical risk than midwives. Such dichotomies oversimplify and obscure the complexity of the process. This study examines pregnancy-related risk perception in women and healthcare professionals, and what women and professionals believe about each other’s risk perception. Methods: A cross sectional survey of set in UK maternity services. Participants were doctors working in obstetrics (N = 53), midwives (N = 59), pregnant women (N = 68). Participants were recruited in person from two hospitals. Doctors were also recruited online. Participants completed a questionnaire measuring the degree of perceived risk in various childbirth-related scenarios; and the extent to which they believed others agreed with them about the degree of risk generally involved in childbirth. Main outcome measures were the degree of risk perceived to the mother in baby in pregnancy scenarios, and beliefs about own perception of risk in comparison to their own group and other groups. Results: There were significant differences in total risk scores between pregnant women, doctors and midwives in perception of risk to the mother in 68/80 scenarios. Doctors most frequently rated risks lowest. Total scores for perceived risk to the baby were not significantly different. There was substantial variation within each group. There was more agreement on the ranking of scenarios according to risk. Each group believed doctors perceived most risk whereas actually doctors most frequently rated risks lowest. Each group incorrectly believed their peers rated risk similarly to themselves. Conclusions: Individuals cannot assume others share their perception of risk or that they make correct assessments regarding others’ risk perception. Further research should consider what factors are taken into account when making risk assessments

Ground-state cooling of a trapped ion Using long-wavelength radiation

We demonstrate ground-state cooling of a trapped ion using radio-frequency (rf) radiation. This is a powerful tool for the implementation of quantum operations, where rf or microwave radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of n¯=0.13(4) after sideband cooling, corresponding to a ground-state occupation probability of 88(7)%. After preparing in the vibrational ground state, we demonstrate motional state engineering by driving Rabi oscillations between the |n=0⟩ and |n=1⟩ Fock states. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost 2 orders of magnitude compared with our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system

HI and OH absorption in the lensing galaxy of MG J0414+0534

We report the detection of \HI 21-cm absorption in the $z=0.96$ early-type lensing galaxy towards MG J0414+0534 with the Green Bank Telescope. The absorption, with total $N_{\rm HI}=1.6 \times 10^{18} (T_{\rm s}/f) {\rm cm}^{-2}$, is resolved into two strong components, probably due to the two strongest lens components, which are separated by 0.4\arcsec. Unlike the other three lenses which have been detected in \HI, J0414+0534 does not exhibit strong OH absorption, giving a OH/\HI column density ratio of N_{\rm OH}/N_{\rm HI}\lapp10^{-6} (for $T_{\rm s}=100$ K, $T_{\rm x}=10$ K and $f_{\rm HI}=f_{\rm OH}=1$). This underabundance of molecular gas may indicate that the extreme optical--near-IR colour ($V-K=10.26$) along the line-of-sight is not due to the lens. We therefore suggest that despite the strong upper limits on molecular absorption at the quasar redshift, as traced by millimetre lines, the extinction occurs primarily in the quasar host galaxy.Comment: Accepted by MNRAS Letters, 5 (and a bit) pages, 5 figure

High spatial resolution observations of CUDSS14A: a SCUBA-selected ultraluminous galaxy at high redshift

The definitive version is available at www.blackwell-synergy.com '. Copyright Blackwell Publishing DOI : 10.1046/j.1365-8711.2000.03822.xWe present a high-resolutionmillimetre interferometric image of the brightest SCUBA- selected galaxy from the Canada-UK deep SCUBA survey (CUDSS). We make a very clear detection at 1.3 mm, but fail to resolve any structure in the source.Peer reviewe

Do the constants of nature couple to strong gravitational fields?

Recently, white dwarf stars have found a new use in the fundamental physics community. Many prospective theories of the fundamental interactions of Nature allow traditional constants, like the fine structure constant $\alpha$, to vary in some way. A study by Berengut et al. (2013) used the Fe/Ni V line measurements made by Preval et al. (2013) from the hot DA white dwarf G191-B2B, in an attempt to detect any variation in $\alpha$. It was found that the Fe V lines indicated an increasing alpha, whereas the Ni V lines indicated a decreasing alpha. Possible explanations for this could be misidentification of the lines, inaccurate atomic data, or wavelength dependent distortion in the spectrum. We examine the first two cases by using a high S/N reference spectrum from the hot sdO BD+28$^{\circ}$4211 to calibrate the Fe/Ni V atomic data. With this new data, we re-evaluate the work of Berengut et al. (2013) to derive a new constraint on the variation of alpha in a gravitational field.Comment: 4 pages, 2 figures: To appear in the proceedings of the "19th European White Dwarf Workshop" in Montreal, Canada, 201

No more time to stay ‘single’ in the detection of Anisakis pegreffii, A. simplex (s. s.) and hybridization events between them: a multi-marker nuclear genotyping approach

A multi-marker nuclear genotyping approach was performed on larval and adult specimens of Anisakis spp. (N = 689) collected from fish and cetaceans in allopatric and sympatric areas of the two species Anisakis pegreffii and Anisakis simplex (s. s.), in order to: (1) identify specimens belonging to the parental taxa by using nuclear markers (allozymes loci) and sequence analysis of a new diagnostic nuclear DNA locus (i.e. partial sequence of the EF1 α−1 nDNA region) and (2) recognize hybrid categories. According to the Bayesian clustering algorithms, based on those markers, most of the individuals (N = 678) were identified as the parental species [i.e. A. pegreffii or A. simplex (s. s.)], whereas a smaller portion (N = 11) were recognized as F1 hybrids. Discordant results were obtained when using the polymerase chain reaction–restriction fragment length polymorphisms (PCR–RFLPs) of the internal transcribed spacer (ITS) ribosomal DNA (rDNA) on the same specimens, which indicated the occurrence of a large number of ‘hybrids’ both in sympatry and allopatry. These findings raise the question of possible misidentification of specimens belonging to the two parental Anisakis and their hybrid categories derived from the application of that single marker (i.e. PCR–RFLPs analysis of the ITS of rDNA). Finally, Bayesian clustering, using allozymes and EF1 α−1 nDNA markers, has demonstrated that hybridization between A. pegreffii and A. simplex (s. s.) is a contemporary phenomenon in sympatric areas, while no introgressive hybridization takes place between the two species