70 research outputs found
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Predicting space climate change
The recent decline in the open magnetic flux of the Sun heralds the end of the Grand Solar Maximum (GSM) that has persisted throughout the space age, during which the largestâfluence Solar Energetic Particle (SEP) events have been rare and Galactic Cosmic Ray (GCR) fluxes have been relatively low. In the absence of a predictive model of the solar dynamo, we here make analogue forecasts by studying past variations of solar activity in order to evaluate how longâterm change in space climate may influence the hazardous energetic particle environment of the Earth in the future. We predict the probable future variations in GCR flux, nearâEarth interplanetary magnetic field (IMF), sunspot number, and the probability of large SEP events, all deduced from cosmogenic isotope abundance changes following 24 GSMs in a 9300âyear record
Blue-Light-Emitting Color Centers in High-Quality Hexagonal Boron Nitride
Light emitters in wide band gap semiconductors are of great fundamental
interest and have potential as optically addressable qubits. Here we describe
the discovery of a new color center in high-quality hexagonal boron nitride
(h-BN) with a sharp emission line at 435 nm. The emitters are activated and
deactivated by electron beam irradiation and have spectral and temporal
characteristics consistent with atomic color centers weakly coupled to lattice
vibrations. The emitters are conspicuously absent from commercially available
h-BN and are only present in ultra-high-quality h-BN grown using a
high-pressure, high-temperature Ba-B-N flux/solvent, suggesting that these
emitters originate from impurities or related defects specific to this unique
synthetic route. Our results imply that the light emission is activated and
deactivated by electron beam manipulation of the charge state of an
impurity-defect complex
Improving children's social care services: results of a feasability study.
This report sets out the findings of a feasibility study that aimed to understand how to define âgoodâ childrenâs social care services and how to assess whether they have improved. The intention was for the feasibility study to support a larger project exploring the processes involved in improving childrenâs social care services. The key findings of the study are:
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There is a lack of consistent expectations about outcomes for childrenâs social care services and what indicators should be used to monitor them. There is mixed evidence about the features that characterise good childrenâs social care services, and a significant proportion of it is based on expert opinion and has not been tested quantitatively.
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Analysis of the relationship between outcome data for children in need collated nationally by the Department for Education and Ofsted ratings of childrenâs services found very little association. There did not seem to be any pattern in terms of the local authorities that were in the top or bottom percentiles for child outcome. Only one child outcome variable and one workforce variable had a statistically significant relationship with the Ofsted ratings.
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Before proceeding with a study exploring how childrenâs social care services improve, it is important to identify an outcomes framework that a wide range of stakeholders agree is appropriate and to establish a set of indicators that reflect these outcomes and that could be collected and collated at a national level.
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The study team concluded that at this time it is not feasible to go ahead with the main project as originally envisaged, and instead to focus on how to create an outcomes framework and establish an appropriate set of indicators
Planet Migration and Disk Destruction due to Magneto-Centrifugal Stellar Winds
This paper investigates the influence of magneto-centrifugally driven or
simply magnetic winds of rapidly-rotating, strongly-magnetized T Tauri stars in
causing the inward or outward migration of close-in giant planets. The
azimuthal ram pressure of the magnetized wind acting on the planet tends to
increase the planet's angular momentum and cause outward migration if the
star's rotation period is less than the planet's orbital period . In
the opposite case, , the planet migrates inward. Thus, planets
orbiting at distances larger (smaller) than
tend to be pushed outward (inward), where is the rotation period of the
star assumed to have the mass of the sun. The magnetic winds are likely to
occur in T Tauri stars where the thermal speed of the gas close to the star is
small, where the star's magnetic field is strong, and where the star rotates
rapidly. The time-scale for appreciable radial motion of the planet is
estimated as Myr. A sufficiently massive close-in planet may
cause tidal locking and once this happens the radial migration due to the
magnetic wind ceases. The magnetic winds are expected to be important for
planet migration for the case of a multipolar magnetic field rather than a
dipole field where the wind is directed away from the equatorial plane and
where a magnetospheric cavity forms. The influence of the magnetic wind in
eroding and eventually destroying the accretion disk is analyzed. A momentum
integral is derived for the turbulent wind/disk boundary layer and this is used
to estimate the disk erosion time-scale as Myr, with the lower
value favored.Comment: 8 pages, 6 figure
Phenological changes in the Southern Hemisphere
Current evidence of phenological responses to recent climate change is substantially biased towards northern hemisphere temperate regions. Given regional differences in climate change, shifts in phenology will not be uniform across the globe, and conclusions drawn from temperate systems in the northern hemisphere might not be applicable to other regions on the planet. We conduct the largest meta-analysis to date of phenological drivers and trends among southern hemisphere species, assessing 1208 long-term datasets from 89 studies on 347 species. Data were mostly from Australasia (Australia and New Zealand), South America and the Antarctic/subantarctic, and focused primarily on plants and birds. This meta-analysis shows an advance in the timing of spring events (with a strong Australian data bias), although substantial differences in trends were apparent among taxonomic groups and regions. When only statistically significant trends were considered, 82% of terrestrial datasets and 42% of marine datasets demonstrated an advance in phenology. Temperature was most frequently identified as the primary driver of phenological changes; however, in many studies it was the only climate variable considered. When precipitation was examined, it often played a key role but, in contrast with temperature, the direction of phenological shifts in response to precipitation variation was difficult to predict a priori . We discuss how phenological information can inform the adaptive capacity of species, their resilience, and constraints on autonomous adaptation. We also highlight serious weaknesses in past and current data collection and analyses at large regional scales (with very few studies in the tropics or from Africa) and dramatic taxonomic biases. If accurate predictions regarding the general effects of climate change on the biology of organisms are to be made, data collection policies focussing on targeting data-deficient regions and taxa need to be financially and logistically supported
Local Sensing of Absolute Refractive Index During Protein-Binding using Microlasers with Spectral Encoding
Multiplexed, specific, and sensitive detection of antigens is critical for the rapid and accurate diagnosis of disease and the informed development of personalized treatment plans. Here, it is shown that polymer microsphere lasers can be used as photonic sensors to monitor and quantify direct surface binding of biomolecules via changes in the refractive index. The unique spectral signature of each individual laser can be used to find their size and effective refractive index which adds a new encoding dimension when compared to conventional fluorescent beads. Antibody-functionalized microlasers selectively detect protein binding, as demonstrated for Immunoglobulin G and C-reactive protein, and have the ability to resolve different stages of the multilayer surface modification. Moreover, by continuously monitoring single lasers, the possibility of real-time monitoring of binding dynamics between antigens in solution phase and the immobilized antibodies is demonstrated. For multiplexed detection, the microlasers are employed in a flow cytometer configuration, with fast spectral detection and identification of microlasers with and without antigen binding. It is envisioned that by combining microlasers with well-established surface modification chemistries and flow geometries, the multiplexing ability of microbead immunoassays can be strongly increased while also opening avenues for single-cell profiling within heterogeneous cell populations
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Charting Ethical Tensions in Multispecies Technology Research through Beneficiary-Epistemology Space
While ethical challenges are widely discussed in HCI, far less is reported about the ethical processes that researchers routinely navigate. We reflect on a multispecies project that negotiated an especially complex ethical approval process. Cat Royale was an artist-led exploration of creating an artwork to engage audiences in exploring trust in autonomous systems. The artwork took the form of a robot that played with three cats. Gaining ethical approval required an extensive dialogue with three Institutional Review Boards (IRBs) covering computer science, veterinary science and animal welfare, raising tensions around the welfare of the cats, perceived benefits and appropriate methods, and reputational risk to the University. To reveal these tensions we introduce beneficiary-epistemology space, that makes explicit who benefits from research (humans or animals) and underlying epistemologies. Positioning projects and IRBs in this space can help clarify tensions and highlight opportunities to recruit additional expertise
Sticky Stories: Joe Orton, Queer History, Queer Dramaturgy
This paper investigates the resonances of Ortonâs work for contemporary queer audiences. By presenting potential reasons for the rise and fall in popularity and visibility of Ortonâs work for queer and gay audiences through the 1980s and 1990s, this paper looks to the queer context in which Joe Ortonâs work developed in order to explore the queer social history into which it fits. Â This sense of queer history is linked to contemporary notions of queer theorising about temporalities and queer dramaturgy, which offers potentially novel ways of engaging with Ortonâs work queerly without twisting it to fit a âneatâ reading, in part because such readings tend to âsmooth outâ the more difficult elements of the work. Â In particular, the paper explores the theatrical form of farce, often articulated as conservative, in relation to queer positions, which are quite the opposite. Â In so doing, the paper, by way of queer temporalities and work on queer dramaturgies, sketches out a reading strategy that does not ignore Ortonâs more difficult or stickier elements, in particular his treatment of women and race
Does size matter for horny beetles? A geometric morphometric analysis of interspecific and intersexual size and shape variation in Colophon haughtoni Barnard, 1929, and C. kawaii Mizukami, 1997 (Coleoptera: Lucanidae)
Colophon is an understudied, rare and endangered stag beetle genus with all species endemic to isolated mountain peaks in South Africaâs Western Cape. Geometric morphometrics was used to analyse intersexual and interspecific variation of size and shape in the mandibles, heads, pronota and elytra of two sympatric species: Colophon haughtoni and Colophon kawaii. All measured structures showed significant sexual dimorphism, which may result from male-male competition for females. Female mandibles were too small and featureless for analysis, but male Colophon beetles possess large, ornate mandibles for fighting. Males had significantly larger heads and pronota that demonstrated shape changes which may relate to resource diversion to the mandibles and their supporting structures. Females are indistinguishable across species, but males were accurately identified using mandibles, heads and pronota. Male C. kawaii were significantly larger than C. haughtoni for all structures. These results support the species status of C. kawaii, which is currently in doubt due to its hybridisation with C. haughtoni. We also demonstrate the value of geometric morphometrics as a tool which may aid Colophon conservation by providing biological and phylogenetic insights and enabling species identification
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