We examine magnetic field data obtained by the Cassini spacecraft on a sequence of high‐latitude orbits in Saturn's magnetosphere spanning October 2006 to May 2007 to determine whether ...planetary‐period oscillations are present on polar open field lines, such as have been found previously in near‐equatorial magnetic field data. Such oscillations are found generally to be present with amplitudes ∼0.5–1 nT, somewhat smaller than the few nT amplitudes typical of the quasi‐dipolar equatorial region. The polarization characteristics in the northern and southern polar regions are determined and found to differ significantly from those in the equatorial region. The phases of the oscillations in the northern and southern hemispheres are also determined relative to the equatorial oscillations, and hence relative to each other, requiring extension of the equatorial oscillation phase model to the end of 2007, spanning the interval of high‐latitude orbits. The results show that the overall pattern of field oscillations is not consistent with a rotating external current system that mimics a rotating transverse dipole in the outer regions. Rather, we suggest that the overall field perturbations are associated with a rotating partial ring current and its field‐aligned closure currents, the latter favoring the southern ionosphere during the southern summer conditions examined. A physical picture is presented that links together observed planetary‐period modulations in the middle and outer magnetospheric field, plasma, and radio emissions that may be subject to further test and makes predictions as to how these phenomena will evolve during future Saturn equinox and northern summer conditions.
Bringing together leaf trait data spanning 2,548 species and 175 sites we describe, for the first time at global scale, a universal spectrum of leaf economics consisting of key chemical, structural ...and physiological properties. The spectrum runs from quick to slow return on investments of nutrients and dry mass in leaves, and operates largely independently of growth form, plant functional type or biome. Categories along the spectrum would, in general, describe leaf economic variation at the global scale better than plant functional types, because functional types overlap substantially in their leaf traits. Overall, modulation of leaf traits and trait relationships by climate is surprisingly modest, although some striking and significant patterns can be seen. Reliable quantification of the leaf economics spectrum and its interaction with climate will prove valuable for modelling nutrient fluxes and vegetation boundaries under changing land-use and climate.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
To explore young people's perceptions of alcohol advertising on Facebook and investigate perceived compliance with the Alcohol Beverages Advertising Code (ABAC).
An online cross-sectional survey with ...172 Australians aged 16-29 years recruited from a market research website and via Facebook. We compiled advertisements from six popular alcohol brands' Australian Facebook pages and asked respondents for their perceptions and interpretations in open and closed-ended questions.
Open-ended responses most commonly indicated that the main messages of the advertisements related to social success. In closed-ended questions, respondents perceived advertisements implied that alcohol facilitated relaxation (67%), improved mood (65%), social success (57%) and confidence (49%).
Young people identified the main themes of alcohol advertising on Facebook as related to social success and significant improvement in mood. Young people's interpretations of Facebook alcohol advertising suggest breaches of ABAC guidelines. Strengthening the enforcement and application of the ABAC and social media alcohol advertising policies is justified.
The Extended Contact Effect Wright, Stephen C; Aron, Arthur; McLaughlin-Volpe, Tracy ...
Journal of personality and social psychology,
07/1997, Letnik:
73, Številka:
1
Journal Article
Recenzirano
The extended contact hypothesis proposes that knowledge that an in-group member has a close relationship with an out-group member can lead to more positive intergroup attitudes. Proposed mechanisms ...are the in-group or out-group member serving as positive exemplars and the inclusion of the out-group member's group membership in the self. In Studies 1 and 2, respondents knowing an in-group member with an out-group friend had less negative attitudes toward that out-group, even controlling for dispositional variables and direct out-group friendships. Study 3, with constructed intergroup-conflict situations (on the robbers cave model), found reduced negative out-group attitudes after participants learned of cross-group friendships. Study 4, a minimal group experiment, showed less negative out-group attitudes for participants observing an apparent in-group-out-group friendship.
In this paper, we experimentally study and compare the effects of three combinations of multiple tuned liquid column dampers (MTLCDs) on the dynamic performance of a model floating tension-leg ...platform (TLP) structure in a wave basin. The structural stability and safety of the floating structure during operation and maintenance is of concern for the performance of a renewable energy device that it might be supporting. The dynamic responses of the structure should thus be limited for these renewable energy devices to perform as intended. This issue is particularly important during the operation of a TLP in extreme weather conditions. Tuned liquid column dampers (TLCDs) can use the power of sloshing water to reduce surge motions of a floating TLP exposed to wind and waves. This paper demonstrates the potential of MTLCDs in reducing dynamic responses of a scaled TLP model through an experimental study. The potential of using output-only statistical markers for monitoring changes in structural conditions is also investigated through the application of a delay vector variance (DVV) marker for different conditions of control for the experiments.
Positive youth development (PYD) models are effective in improving adolescent sexual health. Adolescent programs including peer educators, parents and the wider community also demonstrate ...effectiveness in improving sexual health outcomes. An innovative Positive Adolescent Sexual Health (PASH) Conference model has been introduced in Northern NSW, Australia. It is run by the North Coast PASH Consortium, which is based on a health promotion framework. It takes a positive and holistic approach to sexual health education, and incorporates peer educators, parents, community workers and teachers. This study provides an introductory evaluation of the PASH Conference and identifies areas for increased effectiveness. It is intended as an early piece of research to inform future evaluations and to provide introductory information for public health educators.
Data collection included semi-structured interviews with 13 key stakeholders of the PASH Conference. Interviews were recorded, transcribed verbatim and analysed using deductive thematic analysis.
Subjects included 2 teachers, 2 parents, 2 youth conference workers, 2 organisers, 2 presenters and 3 Peer Educators engaging Peers (PEEPs). Stakeholders perceived that young people were engaged to strengthen their sexual health and wellbeing due to many factors. These followed 3 themes: a safe and open learning environment, empowerment of young people and involvement of the support system and broader community. Multiple recommendations were identified across 2 themes: changes to conference format and planning, and enhancing stakeholder engagement.
The PASH Conference is a promising new youth development design promoting positive adolescent sexual health, which may provide a feasible model for public health educators to trial. Elements of the conference identified as engaging to youth align well with those in PYD research literature. This study provides an early piece of research to inform the design of future research on the PASH Conference including evaluation of behavioural outcomes. It provides introductory information to inform PASH Conference development to further increase its effectiveness.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
We report the design, fabrication and characterization of a microfabricated surface-electrode ion trap that supports controlled transport through the two-dimensional intersection of linear trapping ...zones arranged in a 90° cross. The trap is fabricated with very large scalable integration techniques which are compatible with scaling to a large quantum information processor. The shape of the radio-frequency electrodes is optimized with a genetic algorithm to reduce axial pseudopotential barriers and minimize ion heating during transport. Seventy-eight independent dc control electrodes enable fine control of the trapping potentials. We demonstrate reliable ion transport between junction legs and determine the rate of ion loss due to transport. Doppler-cooled ions survive more than 105 round-trip transits between junction legs without loss and more than 65 consecutive round trips without laser cooling.
ABSTRACT We present integral field spectrograph (IFS) with laser guide star adaptive optics (LGS-AO) observations of z ∼ 2 quasi-stellar objects (QSOs) designed to resolve extended nebular line ...emission from the host galaxy. Our data was obtained with W. M. Keck and Gemini North Observatories, using OSIRIS and NIFS coupled with the LGS-AO systems, respectively. We have conducted a pilot survey of five QSOs, three observed with NIFS+AO and two observed with OSIRIS+AO at an average redshift of z = 2.2. We demonstrate that the combination of AO and IFSs provides the necessary spatial and spectral resolutions required to separate QSO emission from its host. We present our technique for generating a point-spread function (PSF) from the broad-line region of the QSO and performing PSF subtraction of the QSO emission to detect the host galaxy emission at a separation of ∼0 2 (∼1.4 kpc). We detect H narrow-line emission for two sources, SDSS J1029+6510 (zH = 2.182) and SDSS J0925+0655 (zH = 2.197), that have evidence for both star formation and extended narrow-line emission. Assuming that the majority of narrow-line H emission is from star formation, we infer a star formation rate (SFR) for SDSS J1029+6510 of 78.4 M yr−1 originating from a compact region that is kinematically offset by 290-350 km s−1. For SDSS J0925+0655 we infer a SFR of 29 M yr−1 distributed over three clumps that are spatially offset by ∼7 kpc. The null detections on three of the QSOs are used to infer surface brightness limits and we find that at 1.4 kpc from the QSO the un-reddened star formation limit is 0.3 M yr−1 kpc−2. If we assume typical extinction values for z = 2 type-1 QSOs, the dereddened SFR for our null detections would be 0.6 M yr−1 kpc−2. These IFS observations indicate that while the central black hole is accreting mass at 10%-40% of the Eddington rate, if star formation is present in the host (1.4-20 kpc) it would have to occur diffusely with significant extinction and not in compact, clumpy regions.
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