100,521 research outputs found
SunSmart? Skin cancer knowledge and preventive behaviour in a British population representative sample
No full textThe incidence of skin cancer has risen rapidly in the UK over the last 20 years, prompting public health organizations to try and raise awareness of the dangers of sun exposure and the need to practice sun-safe behaviour. This study aimed to assess baseline levels of sun-safe knowledge and behaviour in a British population-representative sample, prior to the launch of Cancer Research UK's 'SunSmart' campaign. A face-to-face survey was conducted through the Office for National Statistics as part of their Omnibus survey. In total, 1848 men and women aged 18 and over were interviewed. Knowledge of what to do to reduce skin cancer risk was modest. Two-thirds mentioned avoiding the sun by seeking shade, 50% mentioned covering up and only 43% said to use high factor sunscreen. Practice of sun-safe behaviours was also poor, with only one-third saying they sought shade, covered up or used high factor sunscreen to protect themselves from the sun. Men and those from lower socioeconomic groups were least informed and least likely to report using sun-protective behaviours. Increases in both knowledge and use of appropriate sun-protective behaviours are needed if skin cancer incidence rates are to decrease
Extension of the sun-synchronous Orbit
No full textThrough careful consideration of the orbit perturbation force due to the oblate nature of the primary body a secular variation of the ascending node angle of a near-polar orbit can be induced without expulsion of propellant. Resultantly, the orbit perturbations can be used to maintain the orbit plane in, for example, a near-perpendicular (or at any other angle) alignment to the Sun-line throughout the full year of the primary body; such orbits are normally termed Sun-synchronous orbits [1, 2]. Sun-synchronous orbits about the Earth are typically near-circular Low-Earth Orbits (LEOs), with an altitude of less than 1500 km. It is normal to design a LEO such that the orbit period is synchronised with the rotation of the Earth‟s surface over a given period, such that a repeating ground-track is established. A repeating ground-track, together with the near-constant illumination conditions of the ground-track when observed from a Sun-synchronous orbit, enables repeat observations of a target over an extended period under similar illumination conditions [1, 2]. For this reason, Sun-synchronous orbits are extensively used by Earth Observation (EO) platforms, including currently the Environmental Satellite (ENVISAT), the second European Remote Sensing satellite (ERS-2) and many more. By definition, a given Sun-synchronous orbit is a finite resource similar to a geostationary orbit. A typical characterising parameter of a Sun-synchronous orbit is the Mean Local Solar Time (MLST) at descending node, with a value of 1030 hours typical. Note that ERS-1 and ERS-2 used a MLST at descending node of 1030 hours ± 5 minutes, while ENVISAT uses a 1000 hours ± 5 minutes MLST at descending node [3]. Following selection of the MLST at descending node and for a given desired repeat ground-track, the orbit period and hence the semi-major axis are fixed, thereafter assuming a circular orbit is desired it is found that only a single orbit inclination will enable a Sun-synchronous orbit [2]. As such, only a few spacecraft can populate a given repeat ground-track Sun-synchronous orbit without compromise, for example on the MLST at descending node. Indeed a notable feature of on-going studies by the ENVISAT Post launch Support Office is the desire to ensure sufficient propellant remains at end-of-mission for re-orbiting to a graveyard orbit to ensure the orbital slot is available for future missions [4]. An extension to the Sun-synchronous orbit is considered using an undefined, non-orientation constrained, low-thrust propulsion system. Initially the low-thrust propulsion system will be considered for the free selection of orbit inclination and altitude while maintaining the Sun-synchronous condition. Subsequently the maintenance of a given Sun-synchronous repeat-ground track will be considered, using the low-thrust propulsion system to enable the free selection of orbit altitude. An analytical expression will be developed to describe these extensions prior to then validating the analytical expressions within a numerical simulation of a spacecraft orbit. Finally, an analysis will be presented on transfer and injection trajectories to these orbits
POLAR investigation of the Sun—POLARIS
No full textThe POLAR Investigation of the Sun (POLARIS) mission uses a combination of a gravity assist and solar sail propulsion to place a spacecraft in a 0.48 AU circular orbit around the Sun with an inclination of 75° with respect to solar equator. This challenging orbit is made possible by the challenging development of solar sail propulsion. This first extended view of the high-latitude regions of the Sun will enable crucial observations not possible from the ecliptic viewpoint or from Solar Orbiter. While Solar Orbiter would give the first glimpse of the high latitude magnetic field and flows to probe the solar dynamo, it does not have sufficient viewing of the polar regions to achieve POLARIS’s primary objective: determining the relation between the magnetism and dynamics of the Sun’s polar regions and the solar cycle
Evidence for the decay B0→J/ψω and measurement of the relative branching fractions of meson decays to J/ψη and J/ψη′
No full textFirst evidence of the B 0 → J / ψ ω decay is found and the B s 0 → J / ψ η and B s 0 → J / ψ η ′ decays are studied using a dataset corresponding to an integrated luminosity of 1.0 fb -1 collected by the LHCb experiment in proton-proton collisions at a centre-of-mass energy of sqrt(s) = 7 TeV. The branching fractions of these decays are measured relative to that of the B 0 → J / ψ ρ 0 decay:frac(B (B 0 → J / ψ ω), B (B 0 → J / ψ ρ 0)) = 0.89 ± 0.19 (stat) - 0.13 + 0.07 (syst),frac(B (B s 0 → J / ψ η), B (B 0 → J / ψ ρ 0)) = 14.0 ± 1.2 (stat) - 1.5 + 1.1 (syst) - 1.0 + 1.1 (frac(f d, f s)),frac(B (B s 0 → J / ψ η ′), B (B 0 → J / ψ ρ 0)) = 12.7 ± 1.1 (stat) - 1.3 + 0.5 (syst) - 0.9 + 1.0 (frac(f d, f s)), where the last uncertainty is due to the knowledge of f d / f s, the ratio of b-quark hadronization factors that accounts for the different production rate of B 0 and B s 0 mesons. The ratio of the branching fractions of B s 0 → J / ψ η ′ and B s 0 → J / ψ η decays is measured to befrac(B (B s 0 → J / ψ η ′), B (B s 0 → J / ψ η)) = 0.90 ± 0.09 (stat) - 0.02 + 0.06 (syst)
Perspectives on Identity, Migration, and Displacement
No full textPerspectives on Identity, Migration, and Displacement -- edited by Steven Tötösy de Zepetnek, I-Chun Wang, and Hsiao-Yu Sun (Kaohsiung: National Sun Yat-sen University Press, 2010. ISBN 9789860235418 209 pages, bibliography, index) is a collection of articles about sociological and literary aspects of identity formation as a consequence of (im)migration. (Im)migration results in the problematics of assimilation and hybridity and in postcolonial scholarship, in particular, attention is paid to the concept of migration termed Creolization on the ground that cultural contact, cultural transmission, and cultural transformation result in the creation of new cultures. Copyright release by National Sun Yat-sen University to the authors 2013
APC/C and SCFcyclin F Constitute a Reciprocal Feedback Circuit Controlling S-Phase Entry
No full textSummaryThe anaphase promoting complex/cyclosome (APC/C) is an ubiquitin ligase and core component of the cell-cycle oscillator. During G1 phase, APC/C binds to its substrate receptor Cdh1 and APC/CCdh1 plays an important role in restricting S-phase entry and maintaining genome integrity. We describe a reciprocal feedback circuit between APC/C and a second ubiquitin ligase, the SCF (Skp1-Cul1-F box). We show that cyclin F, a cell-cycle-regulated substrate receptor (F-box protein) for the SCF, is targeted for degradation by APC/C. Furthermore, we establish that Cdh1 is itself a substrate of SCFcyclin F. Cyclin F loss impairs Cdh1 degradation and delays S-phase entry, and this delay is reversed by simultaneous removal of Cdh1. These data indicate that the coordinated, temporal ordering of cyclin F and Cdh1 degradation, organized in a double-negative feedback loop, represents a fundamental aspect of cell-cycle control. This mutual antagonism could be a feature of other oscillating systems
Characteristics of sun bear chest marks and their patterns of individual variation
No full textAnimal coloration is widely involved in a variety of social interactions, and mammals can convey information to conspecifics by visual signals, such as colored or contrasting body marks. The sun bear (Helarctos malayanus) has a vibrant and unusual chest mark. Here, we describe the characteristics of sun bear chest marks and their patterns of individual variation by (1) sex, (2) time, and (3) some biochemistry values related to fur pigmentation. Sun bear pictures were taken from 2009 to 2018 at the Bornean Sun Bear Conservation Centre and Free the Bears sanctuary. We hypothesize that chest marks may serve in conspecific communication and, thus, we mainly expect that (a) these marks allow for sexual recognition and, thus, they should show remarkable differences by sex; (b) marks do not change over time because their consistency allows for easier intraspecific recognition; and (c) patterns of variation may be dependent on the age and/or physical condition of an individual. The most common shapes of sun bear chest marks (n = 63 M and 108 F) were U (M = 60.3%, F = 57.4%) and V (M = 31.8%, F = 32.4%) shapes. We did not detect differences in shape patterns by sex and, over the years, chest mark shape never changed for the same bear (n = 49 individuals, 16 M and 33 F). The number of dark dots in chest marks showed large amounts of individual variation (mean +/- SD = 37.7 +/- 26.8 dots; range = 1-143), and the quantity of dark dots increased with bear age. The complexity of sun bear chest marks might be related to the existence of complex interactions among individuals of the same species, which may allow for recognition and evaluation of their individual characteristics, such as age and health. Experimental approaches are needed to understand the potential functions of sun bear chest marks
A grounded theory of female adolescent behaviour in the sun: comfort matters.
No full textThe aim of the research was to generate a grounded theory to explain the behaviour of young women in the sun. The study sought to explore the sun-related experiences of
young women in order to gain new insights into the influences upon them. The study was qualitative by design and utilised grounded theory method as developed by Glaser.
Twenty female participants, aged 14 to 17 years old were included in the study. They formed six groups. Thirteen interviews were carried out with the groups and six one-to one interviews took place with individuals. All interviews were semi-structured and were based upon the participants' experiences of being in the sun. Data was analysed using the
constant comparative method of data analysis, concordant with Glaserian grounded theory method. Five explanatory categories emerged from the data; Fitting In, Being Myself,
Being Physically Comfortable, Slipping Up and a core category of Being Comfortable. One of the issues that emerged was that some young women believed their social
acceptance depended on their appearance and they conformed to this end. The theory, derived from the categories, proposes that when in the sun, young women direct their
activities toward meeting physical and psychosocial comfort needs. Comfort matters to them because it has implications for their wellbeing. This thesis contributes to the literature about the behaviours of young women in the sun.
By increasing understanding of the factors that influence them, it also adds to the body of knowledge related to the primary prevention of skin cancer with teenage girls in the United Kingdom. The outcome of the research and its contribution to knowledge is a grounded theory, which explains the basis of the behaviours of young women in the sun. It appears that no other study has explored the experiences of UK adolescent females specifically, in
a qualitative way and with the intention of producing a theory to explain them
Designing a Mouse-Antenna Sun-Tracking Radiometer at 89 GHZ for Atmospheric Emission and Extinction Monitoring
No full textThe design of a millimeter-wave Mouse-Antenna Sun-Tracking radiometer at W band (MASTRad89), capable of measuring both the downwelling emitted atmospheric brightness temperature and the associated extinction over an estimated dynamic range greater than 30 dB, is discussed. The MASTRad89 instrument at W band operates with two equal antennas having the same beam width and an offset from each other by an angle of about 10° (named 'mouse antenna' system). A dedicated efficient solar tracking system allows to follow the apparent movement of the Sun by means a programmed controller. The two narrow-beam antennas share the same radiofrequency superheterodyne front-end chain to carry out simultaneous measurements at W band of both Sun and out-of-the-Sun atmospheric brightness temperature. Using a post-processing software, MASTRad89 can provide the atmospheric path attenuation at W band in any weather conditions, overcoming the saturation problem due to rain which is typical of conventional microwave radiometers
Magnetic fields on young, moderately rotating Sun-like stars - I. HD 35296 and HD 29615
No full textObservations of the magnetic fields of young solar-type stars provide a way to investigate the signatures of their magnetic activity and dynamos. Spectropolarimetry enables the study of these stellar magnetic fields and was thus employed at the Telescope Bernard Lyot and the Anglo-Australian Telescope to investigate two moderately rotating young Sun-like stars, namely HD 35296 (V119 Tau, HIP 25278) and HD 29615 (HIP 21632). The results indicate that both stars display rotational variation in chromospheric indices consistent with their spot activity, with variations indicating a probable long-term cyclic period for HD 35296. Additionally, both stars have complex, and evolving, large-scale surface magnetic fields with a significant toroidal component. High levels of surface differential rotation were measured for both stars. For the F8V star HD 35296 a rotational shear of Delta Omega = 0.22(-0.02)(+0.04) rad d(-1) was derived from the observed magnetic profiles. For the G3V star HD 29615, the magnetic features indicate a rotational shear of Delta Omega = 0.48(-0.12)(+0.11) rad d(-1), while the spot features, with a distinctive polar spot, provide a much lower value of Delta Omega of 0.07(-0.03)(+0.10) rad d(-1). Such a significant discrepancy in shear values between spot and magnetic features for HD 29615 is an extreme example of the variation observed for other lower mass stars. From the extensive and persistent azimuthal field observed for both targets, it is concluded that a distributed dynamo operates in these moderately rotating Sun-like stars, in marked contrast to the Sun's interface-layer dynamo
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