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Using the Longitudinal Surveys of Australian Youth (LSAY) data, this paper aimed to examine if, and to what extent, demographic factors predict students’ participation in science over the age of 16 (post-16). While all the students participating in this study are attending Australian schools, the comprehensiveness of these datasets, together with inclusion of studies from around the world provides a useful reference point for an international audience. Over 7000 students are included in the analysis of this paper. Characteristics of focus in this paper include groups who have been identified as being underrepresented in past studies including Indigenous students, those from lower-socio-economic status (SES) backgrounds, sex differences and immigrants. Among the factors tested, Indigenous status was the strongest negative predictor of post-16 science participation. SES was also a relatively strong predictor of post-16 science participation. Compared to students categorised with an Australian-ancestry, first-generation and foreign-background students were more likely to participate in post-16 science. The findings of this study contribute to existing research on debates about equity and trends in science participation.

We review the physics opportunities of the Future Circular Collider, covering its e+e-, pp, ep and heavy ion programmes. We describe the measurement capabilities of each FCC component, addressing the study of electroweak, Higgs and strong interactions, the top quark and flavour, as well as phenomena beyond the Standard Model. We highlight the synergy and complementarity of the different colliders, which will contribute to a uniquely coherent and ambitious research programme, providing an unmatchable combination of precision and sensitivity to new physics.

In response to the 2013 Update of the European Strategy for Particle Physics (EPPSU), the Future Circular Collider (FCC) study was launched as a world-wide international collaboration hosted by CERN. The FCC study covered an energy-frontier hadron collider (FCC-hh), a highest-luminosity high-energy lepton collider (FCC-ee), the corresponding 100km tunnel infrastructure, as well as the physics opportunities of these two colliders, and a high-energy LHC, based on FCC-hh technology. This document constitutes the third volume of the FCC Conceptual Design Report, devoted to the hadron collider FCC-hh. It summarizes the FCC-hh physics discovery opportunities, presents the FCC-hh accelerator design, performance reach, and staged operation plan, discusses the underlying technologies, the civil engineering and technical infrastructure, and also sketches a possible implementation. Combining ingredients from the Large Hadron Collider (LHC), the high-luminosity LHC upgrade and adding novel technologies and approaches, the FCC-hh design aims at significantly extending the energy frontier to 100TeV. Its unprecedented centre of-mass collision energy will make the FCC-hh a unique instrument to explore physics beyond the Standard Model, offering great direct sensitivity to new physics and discoveries.

CoRoT is a space telescope which aims at studying internal structure of stars and detecting extrasolar planets. We present here a list of transits detected in the light curves of stars observed by CoRoT in two fields in the anti-center direction: the LRa03 one observed during 148 days from 3 October 2009 to 1 March 2010 followed by the SRa03 one from the 5 March 2010 to the 29 March 2010 during 25 days. 5329 light curves for the LRa03 field and 4169 for the SRa03 field were analyzed by the detection team of CoRoT. Then some of the selected exoplanetary candidates have been followed up from the ground. In the LRa03 field, 19 exoplanet candidates have been found, 8 remain unsolved. No secured planet has been found yet. In the SRa03 field, there were 11 exoplanetary candidates among which 6 cases remain unsolved and 3 planets have been found: CoRoT-18b, CoRoT-19b, CoRoT-20b. © 2011 Springer Science+Business Media B.V.

The production of $\rho$ , $\omega$ and $\phi$ vector-mesons, detected through their $\mu\mu$ decay channel, is studied in p-W, S-S, S-Cu and S-U reactions at 200 GeV/c per nucleon incident momentum. Their inclusive cross-sections are determined in various transverse momentum intervals and their dependence on the projectile and target mass numbers is investigated. The relative yield $B_{\mu\mu}\sigma_{\phi}/(B_{\mu\mu}\sigma_{\rho} + B_{\mu\mu}\sigma_{\omega})$ is measured, both as a function of the transverse momentum, pT, and of the collision centrality. While this ratio exhibits no significant dependence with pT, it clearly increases with the centrality of the collision. Effective temperatures deduced from the transverse mass spectra, $d\sigma/dM_T$ , lead to values of $T_{\rho + \omega}$ equal or slightly higher than $T_{\phi}$ . Both these effective temperatures smoothly increase from p-W to S-U reactions.

We present the measurements of charged particle pseudorapidity distributions dNch/dη performed by the NA50 experiment in Pb-Pb collisions at the CERN SPS. Measurements were done at incident energies of 40 GeV (√s = 8.77 GeV) and 158 GeV (√s = 17.3 GeV) per nucleon over a broad impact parameter range. The multiplicity distributions are studied as a function of centrality using the number of participating nucleons(N part ), or the number of binary nucleon-nucleon collisions (Ncoll). Their values at midrapidity exhibit a linear scaling withN part at both energies. Particle yield increases approximately by a factor of 2 betweeny √s = 8.77 GeV and √s = 17.3 GeV.

The main scientific objectives, asteroseismology and search for extrasolar planets for the COROT photometric mission are presented, and its interest in terms of stellar variability. A description of the payload, details of the scientific program, the ground based preparatory observations and bibliography can be found athttp://www.astrsp-mrs.fr/corot/pagecorot.html.

19β,28-Epoxy-23,24-dinor-A-neo-18α-olean-4-en-3-one was obtained from betulin in a total yield of 18%.

EVRIS is the first space experiment dedicated to asteroseismology. It is designed to measure the relative time variations of the flux of several bright stars and to detect their modes of pulsation. As the amplitudes of these oscillations should be very small (a few ppm), the instrument has to perform relative photometry with an extremely high accuracy, i.e. hundred times better than the classical accuracy reached from the ground. The experiment is composed of a star tracker and a photometer, mounted on a pointing platform PAIS. This paper describes the mechanical and optical design and the performance of EVRIS, as well as the properties of the pointing system. It is shown that the EVRIS/PAIS complex meets the scientific specifications for a list of targets well suited for asteroseismology. The EVRIS collaboration is composed of: G. Epstein, J.P. Michel, F. Rakotoarivelo, F. Roubaud and A. Mangeney Observatoire de Paris (DESPA) 92195 Meudon, France

We searched for long-lived strange quark matter particles, so-calledstrangelets, and studied particle and antiparticle production in Pb+Pb collisions at 158 GeV/c per nucleon at zero degree production angle. We give upper limits for the production of strangelets covering a mass to charge ratio up to 120 GeV/c 2 and lifetimest lab>1.2 μs and plot invariant differential production cross sections as a function of rapidity for a variety of particles.

The production of low mass dimuons has been measured in d-C, d-U and S-U collisions at 200 GeV per nucleon, and in Pb-Pb collisions at 160 GeV per nucleon. Theϕ, ρ andω productions in S-U collision [1, 2] are extracted from a new set of data with increased statistic, and are throughϕ/(ω+ρ) ratio compared to first results on deuteron induced production. These new analyses are presented in the limitedM T domain of recent Pb-Pb measurement whose preliminary results are also presented.

Venous thromboembolism is a potentially fatal complication of surgery. The use of graded pressure stockings in combination with unfractionated heparin (UFH) or a low molecular weight heparin (LMWH) appears to be the safest and most effective method of prevention. With some LMWHs, the risk of venous thromboembolism appears to be lower than that associated with the use of standard UFH. A comparison of heparin given before versus after surgery (with all patients receiving graded pressure stockings) is justified. More information on the benefit-risk ratio of minidose warfarin is also required. The risk of pulmonary embolism (PE) following discharge from hospital after general surgery is relatively low and the extended use of heparin may not be justified. The value of graded pressure stockings and minidose warfarin for the prevention of PE should be determined. The risk of late PE after orthopaedic surgery is unknown and also needs to be determined.

There is a wide variety of diuretic-induced metabolic abnormalities of unequal severity. Renal failure can be caused by excessive sodium loss, or by certain drug combinations comprising, for instance, a nonsteroidal anti-inflammatory drug (NSAID) or an ACE inhibitor. Hyponatraemia is uncommon. It is encountered with thiazides, especially among women. A sodium level less than 120 mmol/L may result in neurological complications. Hypokalaemia is frequent and might increase the risk of cardiac arrhythmia. Hyperkalaemia induced by potassium-sparing diuretics is often combined with another contributive cause. Glucidic, lipidic and uric acid abnormalities are common, but their clinical effects are slight. They do not seem to worsen cardiovascular risks among elderly patients. Nevertheless, prescribing diuretics for elderly patients requires special precautions. Reducing the diuretic dose, as is now recommended for treating hypertension, seems to lessen adverse effects, and despite all the adverse reactions just mentioned, it has been proven that diuretics are beneficial in many diseases.

Tentatives to detect chaos in variable stars are presented. Constraints on the accuracy on individual measurements and length of the records, necessary to obtain defenitive conclusions, are discussed. Some directions for future improvements are sketched.

Meson production in proton, oxygen and sulphur interactions with uranium targets at 200 GeV/nucleon is studied. We measure the inclusive meson cross-section d σ/dPT2 and its evolution fromp+U to S+U. The cross-section fitted with an exponential gives an inverse slopePT0 of the order of 210 MeV/c. As a function of the neutral transverse energy,PT0 values show a slight rise followed by a plateau. The normalized difference (σ+−σ−)/σ− between positive and negative meson cross-sections is found to increase withET.

High precision photometry from space is the only technique to detect the nonradial oscillations of a significant set of stars with different masses, ages, angular momentum, chemical composition, as already observed for the Sun. During an observation run of several days, a reasonably small telescope (10 cm) will collect enough photons to detect periodic signals of relative amplitude as low as 10 −6, coherent over this period. The frequency resolution necessary to distinguish the rotational splitting (0.5 μH) will be achieved in increasing the observation run to 20 days.

With the expected availability of new tools for creating patterned ion beams, containing few-nanometer features, it is important to examine the fidelity of registering such patterns in the receiving medium, such as a photoresist layer in a lithographic fabrication process. In this paper, we report experiments exploring the characteristics of ion beam patterning of poly methyl methacrylate (PMMA) and polystyrene (PS) coatings on silicon substrates, with respect to their response as positive / negative resists to patterned low-energy H+, He+ and Ne+ beams. We examine by AFM the feature profiles thus created after solvent development of the polymer layers, and we examine the dependence of the polymer response upon ion species and fluence. Edge resolution ¡Ü20 nm is readily obtained, and broad process windows are identified in fluence ranges around 1013 ions/cm2. Proximity effects are shown to be negligible, except after exposure at very high ion fluences. Granularity within the final pattern features is shown to be a potential concern for high energy, light ion irradiations. Optimization of edge resolution is clearly possible, by appropriate selection of ion species, energy and fluence to suit the receiving medium.

We describe the use of ion beam induced crosslinking to harden the organic matrix material of self-assembled arrays of monodisperse (4 nm) FePt nanoparticles, providing diamondlike carbon barriers to inhibit agglomeration of the nanoparticles under heat treatment. Such stabilization is necessary for the particles to survive the >500°C annealing required for growth of the fct L10 phase of FePt, whose magnetic anisotropy is necessary for application of such arrays for high density recording. Selective area irradiation of continuous nanoparticle coatings, using ion beams patterned over a full disk by stencil mask or with ion projection optics, followed by dissolution of the unexposed coating, is proposed as a means of fabricating extended bit patterns consisting of isolated “islands” of FePt nanoparticles, with characteristic dimensions of tens of nanometers.

Flexible magnetic lithography is a process qualitatively analogous to contact optical lithography which transfers information from a patterned magnetic mask (analog of optical photomask) to magnetic media (analog of photoresist), and is interesting for applications in instantaneous parallel magnetic recording. The magnetic mask consists of patterned soft magnetic material (FeNiCo, FeCo) on a flexible plastic substrate, typically Polyethylene Teraphtalate (PET). When uniformly magnetized media is brought into intimate contact with the magnetic mask, an externally applied magnetic field selectively changes the magnetic orientation in the areas not covered with the soft magnetic material. Flexible substrate of the magnetic mask o.ers superior compliance to magnetic media which is likely to have imperfect flatness and surface particulate contamination.Although magnetic in physical nature, flexible magnetics draws interesting parallels to flexible electronics, especially in challenges of fabrication of sub-micron patterns on thin flexible plastic substrates. We fabricated samples of sub-micron patterned FeCo and FeNiCo magnetic masks on PET substrates by using combined lamination/release process of PET films. Rigid substrates, typically silicon or quartz were initially laminated with PET films and processed using standard fabrication procedures. After completing magnetic mask device fabrication, PET films were released from the rigid substrates.We successfully transferred patterns from magnetic masks to hard disk CrPtCo-based magnetic media. The details of the method, including physics of the magnetic lithography pattern transfer, fabrication of the magnetic mask on flexible PET substrates, lamination and release of PET films, and magnetic force microscopy (MFM) images of the magnetic transition patterns are reported.

The mechanisms and effectiveness of corrosion protection provided by thin ion-beam carbon coatings on Cu, Fe, Mn and Co are discussed. A thin (# 10 Å) layer of protective carbon is produced on metal surfaces by ion-beam dissociation of adventitious or intentional hydrocarbon adsorbates. Below 200°C, oxidation is strongly inhibited, as is corrosion in a humid, sulphurous ambient. Above 200°C, the carbon layer may itself be destroyed by oxidation, due to catalytic action of the metal surface. Thicker PVD carbon (up to 60 Å) was not an effective corrosion barrier, even after ion irradiation. A technique for producing high integrity ion-beam carbon layers of high stability and durability is discussed.

Multilayered metal films including such couples as Ta-Permalloy (Ni80Fe20) play a key role in magnetic recording sensors, where it is important to preserve the integrity of the thin permalloy layer under thermal conditions during processing and subsequent service. Earlier work1 has indicated a fast grain boundary diffusion of Ta in Ni films at temperatures as low as 250°C. In this paper, we report measurements of the kinetics of this diffusion, in the temperature range 300–400°C. For this work, layered Ni/Ta systems were prepared under controlled conditions, annealed in a helium-flow furnace, and characterized by RBS, AES, XRD and SEM. The possible consequences of diffusion on magnetic performance are also discussed.

Thermal interdiffusion mechanisms and kinetics have been studied for Ta-Permalloy (Ni80Fe20), Ta-Ni and Ta-Fe thin film couples, in the temperature range 300°C - 600°C. Interaction modes identified for the Ta-NiFe system include: fast diffusion of Ta into grain boundaries of NiFe, and nucleation and growth of Ni3Ta, with consequent depletion of Ni in the remaining NiFe, and eventual segregation of Fe.