4,644 research outputs found
'I just want a job' : what do we really know about young people in jobs without training?
Over recent years, a central concern of policy has been to drive up post-16 participation rates in full-time education and address the needs of young people not in education, employment or training (NEET). As a result, young people who enter work which is classified as 'without training' at 16/17 have largely been ignored. However, the decision to Raise the Participation Age (RPA) for continuing in learning for all 17-year olds from 2013 and for all 18-year olds from 2015 in England, together with a growing unease about the impact of the current recession on youth unemployment rates, have revived interest in the 'jobs without training' (JWT) group. This paper draws on the findings from two studies: first, a qualitative study in two contrasting local labour markets, of young people in JWT, together with their employers and parents; and second, an evaluation of the Learning Agreement Pilots (LAP), which was the first policy initiative in England targeted at the JWT group. Both studies reveal a dearth of understanding about early labour market entrants and a lack of policy intervention and infrastructure to support the needs of the JWT group throughout the UK. From this, it is concluded that questionable assumptions have been made about the composition and the aspirations of young people in JWT, and their employers, on the basis of little or no evidence. As a consequence, a policy 'quick fix' to satisfy the RPA agenda will not easily be achieved. If the decision to raise the participation age is adopted also by the Welsh and Scottish parliaments, similar challenges may have to be faced
A Vehicular Traffic Flow Model Based on a Stochastic Acceleration Process
A new vehicular traffic flow model based on a stochastic jump process in
vehicle acceleration and braking is introduced. It is based on a master
equation for the single car probability density in space, velocity and
acceleration with an additional vehicular chaos assumption and is derived via a
Markovian ansatz for car pairs. This equation is analyzed using simple driver
interaction models in the spatial homogeneous case. Velocity distributions in
stochastic equilibrium, together with the car density dependence of their
moments, i.e. mean velocity and scattering and the fundamental diagram are
presented.Comment: 27 pages, 6 figure
Multiple diffusion pathways in LixNi0.77Co0.14Al0.09O2 (NCA) Li-ion battery cathodes
Experimental evidence for the presence of two computationally theorised diffusion pathways, namely the oxygen dumbbell hop (ODH) and tetrahedral site hop (TSH), has been given for the first time by muon spin relaxation (µSR) on sub-stoichiometric LixNi0.77Co0.14Al0.09O2. µSR has proven to be a powerful tool that is able to discriminate between diffusion pathways that occur on different timescales on a local level, where bulk electrochemical techniques cannot. Whereas the estimated values of DLi at lithium concentrations of 0.87 and 0.71 were found to be on the order of 10-11 by electrochemical impedance spectroscopy, contributions to diffusion from ODH and TSH were determined to be on the order of 10-11 and 10-10 cm2 s-1, and a factor of four decrease in Ea for both samples, in excellent agreement with theoretical calculations on related compounds. Rietveld refinement of both X-ray and neutron diffraction data was also used to interrogate the local structure of the materials where no contribution from Li+/Ni2+ cation mixing was observed
A seasonal switch in histone deacetylase gene expression in the hypothalamus and their capacity to modulate nuclear signaling pathways
YesSeasonal animals undergo changes in physiology and behavior between summer and winter conditions. These changes are in part driven by a switch in a series of hypothalamic genes under transcriptional control by hormones and, of recent interest, inflammatory factors. Crucial to the control of transcription are histone deacetylases (HDACs), generally acting to repress transcription by local histone modification. Seasonal changes in hypothalamic HDAC transcripts were investigated in photoperiod-sensitive F344 rats by altering the day-length (photoperiod). HDAC4, 6 and 9 were found to change in expression. The potential influence of HDACs on two hypothalamic signaling pathways that regulate transcription, inflammatory and nuclear receptor signaling, was investigated. For inflammatory signaling the focus was on NF-κB because of the novel finding made that its expression is seasonally regulated in the rat hypothalamus. For nuclear receptor signaling it was discovered that expression of retinoic acid receptor beta was regulated seasonally. HDAC modulation of NF-κB-induced pathways was examined in a hypothalamic neuronal cell line and primary hypothalamic tanycytes. HDAC4/5/6 inhibition altered the control of gene expression (Fos, Prkca, Prkcd and Ptp1b) by inducers of NF-κB that activate inflammation. These inhibitors also modified the action of nuclear receptor ligands thyroid hormone and retinoic acid. Thus seasonal changes in HDAC4 and 6 have the potential to epigenetically modify multiple gene regulatory pathways in the hypothalamus that could act to limit inflammatory pathways in the hypothalamus during long-day summer-like conditions.Biotechnology and Biological Sciences Research Council (BBSRC
A major electronics upgrade for the H.E.S.S. Cherenkov telescopes 1-4
The High Energy Stereoscopic System (H.E.S.S.) is an array of imaging
atmospheric Cherenkov telescopes (IACTs) located in the Khomas Highland in
Namibia. It consists of four 12-m telescopes (CT1-4), which started operations
in 2003, and a 28-m diameter one (CT5), which was brought online in 2012. It is
the only IACT system featuring telescopes of different sizes, which provides
sensitivity for gamma rays across a very wide energy range, from ~30 GeV up to
~100 TeV. Since the camera electronics of CT1-4 are much older than the one of
CT5, an upgrade is being carried out; first deployment was in 2015, full
operation is planned for 2016. The goals of this upgrade are threefold:
reducing the dead time of the cameras, improving the overall performance of the
array and reducing the system failure rate related to aging. Upon completion,
the upgrade will assure the continuous operation of H.E.S.S. at its full
sensitivity until and possibly beyond the advent of CTA. In the design of the
new components, several CTA concepts and technologies were used and are thus
being evaluated in the field: The upgraded read-out electronics is based on the
NECTAR readout chips; the new camera front- and back-end control subsystems are
based on an FPGA and an embedded ARM computer; the communication between
subsystems is based on standard Ethernet technologies. These hardware solutions
offer good performance, robustness and flexibility. The design of the new
cameras is reported here.Comment: Proceedings of the 34th International Cosmic Ray Conference, 30 July-
6 August, 2015, The Hague, The Netherland
Heat shock proteins and regulatory T cells
Heat shock proteins (HSPs) are important molecules required for ideal protein function. Extensive research on the functional properties of HSPs indicates that HSPs may be implicated in a wide range of physiological functions including immune function. In the immune system, HSPs are involved in cell proliferation, differentiation, cytokine release, and apoptosis. Therefore, the ability of the immune system, in particular immune cells, to function optimally and in unison with other physiological systems is in part dependent on signaling transduction processes, including bidirectional communication with HSPs. Regulatory T cells (Tregs) are important T cells with suppressive functions and impairments in their function have been associated with a number of autoimmune disorders. The purpose of this paper is to examine the relationship between HSPs and Tregs. The interrelationship between cells and proteins may be important in cellular functions necessary for cell survival and expansion during diseased state
Improving pulsar-timing solutions through dynamic pulse fitting
Precision pulsar timing is integral to the detection of the nanohertz
stochastic gravitational-wave background as well as understanding the physics
of neutron stars. Conventional pulsar timing often uses fixed time and
frequency-averaged templates to determine the pulse times of arrival, which can
lead to reduced accuracy when the pulse profile evolves over time. We
illustrate a dynamic timing method that fits each observing epoch using basis
functions. By fitting each epoch separately, we allow for the evolution of the
pulse shape epoch to epoch. We apply our method to PSR J11035403 and
demonstrate that it undergoes mode changing, making it the fourth millisecond
pulsar to exhibit such behaviour. Our method, which is able to identify and
time a single mode, yields a timing solution with a root-mean-square error of
1.343 , a factor of 1.78 improvement over template fitting on
both modes. In addition, the white-noise amplitude is reduced 4.3 times,
suggesting that fitting the full data set causes the mode changing to be
incorrectly classified as white noise. This reduction in white noise boosts the
signal-to-noise ratio of a gravitational-wave background signal for this
particular pulsar by 32%. We discuss the possible applications for this method
of timing to study pulsar magnetospheres and further improve the sensitivity of
searches for nanohertz gravitational waves.Comment: Accepted in MNRAS, 8 pages, 8 figure
The first GCT camera for the Cherenkov Telescope Array
The Gamma Cherenkov Telescope (GCT) is proposed to be part of the Small Size
Telescope (SST) array of the Cherenkov Telescope Array (CTA). The GCT
dual-mirror optical design allows the use of a compact camera of diameter
roughly 0.4 m. The curved focal plane is equipped with 2048 pixels of
~0.2{\deg} angular size, resulting in a field of view of ~9{\deg}. The GCT
camera is designed to record the flashes of Cherenkov light from
electromagnetic cascades, which last only a few tens of nanoseconds. Modules
based on custom ASICs provide the required fast electronics, facilitating
sampling and digitisation as well as first level of triggering. The first GCT
camera prototype is currently being commissioned in the UK. On-telescope tests
are planned later this year. Here we give a detailed description of the camera
prototype and present recent progress with testing and commissioning.Comment: In Proceedings of the 34th International Cosmic Ray Conference
(ICRC2015), The Hague, The Netherlands. All CTA contributions at
arXiv:1508.0589
Synergistic Effect of Co and Mn Co-Doping on SnO2 Lithium-Ion Anodes
The incorporation of transition metals (TMs) such as Co, Fe, and Mn into SnO2 substantially improves the reversibility of the conversion and the alloying reaction when used as a negative electrode active material in lithium-ion batteries. Moreover, it was shown that the specific benefits of different TM dopants can be combined when introducing more than one dopant into the SnO2 lattice. Herein, a careful characterization of Co and Mn co-doped SnO2 via transmission electron microscopy coupled with energy-dispersive X-ray spectroscopy and X-ray diffraction including Rietveld refinement is reported. Based on this in-depth investigation of the crystal structure and the distribution of the two TM dopants within the lattice, an ex situ X-ray photoelectron spectroscopy and ex situ X-ray absorption spectroscopy were performed to better understand the de-/lithiation mechanism and the synergistic impact of the Co and Mn co-doping. The results specifically suggest that the antithetical redox behaviour of the two dopants might play a decisive role for the enhanced reversibility of the de-/lithiation reaction
FBG-based optical interface to support a multisector antenna in a spectrally efficient fiber radio system
We propose and demonstrate a fiber Bragg grating (FBG)-based optical interface for use in a spectrally efficient fiber-radio network with multisector antennas. The system has the novel feature of being specifically developed for use in existing wavelength-division-multiplexed network infrastructures. The proposed scheme supports transport of a remote local oscillator (LO) and three subcarrier multiplexed data channels, destined for different antenna sectors, using a single wavelength. The composite signal was contained within a 25-GHz band, selected via a 25-GHz dispersion-flattened FBG. Recovery of the LO and data channels is performed via optical filtering, using either a novel single grating incorporating multiple phase shifts or multiple narrow bandwidth gratings. Our measurements show that all channels within the 25-GHz band are successfully recovered with less than 2-dB optical power penalty between channels. The use of the 25-GHz grating exhibits an improvement in sensitivity of 3 dB for all data channels
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