11,414 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
Limits on stable iron in TypeIa supernovae from NIR spectroscopy
We obtained optical and near-infrared spectra of TypeIa supernovae
(SNeIa) at epochs ranging from 224 to 496 days after the explosion. The
spectra show emission lines from forbidden transitions of singly ionised iron
and cobalt atoms. We used non-local thermodynamic equilibrium (NLTE) modelling
of the first and second ionisation stages of iron, nickel, and cobalt to fit
the spectra using a sampling algorithm allowing us to probe a broad parameter
space. We derive velocity shifts, line widths, and abundance ratios for iron
and cobalt. The measured line widths and velocity shifts of the singly ionised
ions suggest a shared emitting region. Our data are fully compatible with
radioactive Ni decay as the origin for cobalt and iron. We compare the
measured abundance ratios of iron and cobalt to theoretical predictions of
various SNIa explosion models. These models include, in addition to
Ni, different amounts of Ni and stable Fe. We can
exclude models that produced only Fe or only Ni in addition to
Ni. If we consider a model that has Ni, Ni, and
Fe then our data imply that these ratios are Fe / Ni
and Ni / Ni .Comment: 10 pages, 7 figures, Accepted for publication in A&
Nebular spectroscopy of SN 2014J: Detection of stable nickel in near infrared spectra
We present near infrared (NIR) spectroscopy of the nearby supernova 2014J
obtained 450 d after explosion. We detect the [Ni II] 1.939 m line
in the spectra indicating the presence of stable Ni in the ejecta. The
stable nickel is not centrally concentrated but rather distributed as the iron.
The spectra are dominated by forbidden [Fe II] and [Co II] lines. We use lines,
in the NIR spectra, arising from the same upper energy levels to place
constraints on the extinction from host galaxy dust. We find that that our data
are in agreement with the high and low found in earlier studies
from data near maximum light. Using a Ni mass prior from near maximum
light -ray observations, we find 0.05 M of stable nickel
to be present in the ejecta. We find that the iron group features are
redshifted from the host galaxy rest frame by 600 km s.Comment: 6 pages, 4 figures, submitted to A&
Tonic inhibition of accumbal spiny neurons by extrasynaptic 4 GABAA receptors modulates the actions of psychostimulants
Within the nucleus accumbens (NAc), synaptic GABAA receptors (GABAARs) mediate phasic inhibition of medium spiny neurons (MSNs) and influence behavioral responses to cocaine. We demonstrate that both dopamine D1- and D2-receptor-expressing MSNs (D-MSNs) additionally harbor extrasynaptic GABAARs incorporating α4, β, and δ subunits that mediate tonic inhibition, thereby influencing neuronal excitability. Both the selective δ-GABAAR agonist THIP and DS2, a selective positive allosteric modulator, greatly increased the tonic current of all MSNs from wild-type (WT), but not from δ−/− or α4−/− mice. Coupling dopamine and tonic inhibition, the acute activation of D1 receptors (by a selective agonist or indirectly by amphetamine) greatly enhanced tonic inhibition in D1-MSNs but not D2-MSNs. In contrast, prolonged D2 receptor activation modestly reduced the tonic conductance of D2-MSNs. Behaviorally, WT and constitutive α4−/− mice did not differ in their expression of cocaine-conditioned place preference (CPP). Importantly, however, mice with the α4 deletion specific to D1-expressing neurons (α4D1−/−) showed increased CPP. Furthermore, THIP administered systemically or directly into the NAc of WT, but not α4−/− or α4D1−/− mice, blocked cocaine enhancement of CPP. In comparison, α4D2−/− mice exhibited normal CPP, but no cocaine enhancement. In conclusion, dopamine modulation of GABAergic tonic inhibition of D1- and D2-MSNs provides an intrinsic mechanism to differentially affect their excitability in response to psychostimulants and thereby influence their ability to potentiate conditioned reward. Therefore, α4βδ GABAARs may represent a viable target for the development of novel therapeutics to better understand and influence addictive behaviors
Thermal emission spectroscopy of the middle atmosphere
The general objective of this research is to obtain, via remote sensing, simultaneous measurements of the vertical distributions of stratospheric temperature, ozone, and trace constituents that participate in the catalytic destruction of ozone (NO(sub y): NO, NO2, NO3, HNO3, ClONO2, N2O5, HNO4; Cl(sub x): HOCl), and the source gases for the catalytic cycles (H2O, CH4, N2O, CF2Cl2, CFCl3, CCl4, CH3Cl, CHF2Cl, etc.). Data are collected during a complete diurnal cycle in order to test our present understanding of ozone chemistry and its associate catalytic cycles. The instrumentation employed is an emission-mode, balloon-borne, liquid-nitrogen-cooled Michelson interferometer-spectrometer (SIRIS), covering the mid-infrared range with a spectral resolution of 0.020 cm(exp -1). Cryogenic cooling combined with the use of extrinsic silicon photoconductor detectors allows the detection of weak emission features of stratospheric gaseous species. Vertical distributions of these species are inferred from scans of the thermal emission of the limb in a sequence of elevation angles. The fourth SIRIS balloon flight was carried out from Palestine, Texas on September 15-16, 1986 with 9 hours of nighttime data (40 km). High quality data with spectral resolution 0.022 cm(exp -1), were obtained for numerous limb sequences. Fifteen stratospheric species have been identified to date from this flight: five species from the NO(sub y) family (HNO3, NO2, NO, ClONO2, N2O5), plus CO2, O3, H2O, N2O, CH4, CCl3F, CCl2F2, CHF2Cl, CF4, and CCl4. The nighttime values of N2O5, ClONO2, and total odd nitrogen have been measured for the first time, and compared to model results. Analysis of the diurnal variation of N2O5 within the 1984 and 1986 data sets, and of the 1984 ClONO2 measurements, were presented in the literature. The demonstrated ability of SIRIS to measure all the major NO(sub y) species, and therefore to determine the partitioning of the nitrogen family over a continuous diurnal cycle, is a powerful tool in the verification and improvement of photochemical modeling
A study of the social and physical environment in catering kitchens and the role of the chef in promoting positive health and safety behaviour
This is the account of a mixed method study of chefs and their kitchens in order to identify the nature of their workplace and how this affects their ability to manage health and safety in the kitchen. It included extended periods of observation, monitoring of physical parameters, analysis of records of reported accidents, and a series of reflexive interviews. The findings were integrated and then fed back in a smaller number of second interviews in order to test whether the findings fitted in with the chefs' understanding of their world. Major factors identified included survival in a market environment, the status of the chef (and the kitchen) within organisations, marked autocracy of chefs, and an increasing tempo building up to service time with commensurate heat, noise, and activity. In particular during the crescendo, a threshold shift in risk tolerance was identified. The factors, their interplay, and their implications for health and safety in the catering kitchen are discussed
Trophic Conditions and Planktonic Processes of Semi-arid Floodplain Lakes Inundated with Environmental Flows
Shallow floodplain lakes are critical components of semi-arid floodplain wetland systems. Delivery of environmental flows that aim to sustain ecological processes of semi-arid floodplain wetlands has enhanced inundation of shallow lakes in inland Australia. To maximise environmental flow outcomes to support floodplain productivity and ecosystem functions, environmental managers would benefit from knowing whether semi-arid floodplain lakes function as a sink or source of atmospheric carbon. We investigated abiotic conditions, and rates of planktonic respiration and primary productivity of phytoplankton during summer under environmental flow conditions in three floodplain lakes of the lower Murrumbidgee River, Australia. All lakes showed mesoeutrophic to hypereutrophic characteristics and significant within- and between-lake variability in abiotic conditions, planktonic processes, and associated carbon balance. Nevertheless, the mean net primary productivity of phytoplankton in the lakes (364-1,674 mg C m-2 day-1) were up to about three times greater than in other semi-arid floodplain wetlands of southeast Australia. Therefore, shallow floodplain lakes in semi-arid regions have great potential to function as a sink of atmospheric carbon through planktonic metabolism during summer. A spatial hierarchical framework for lake functional response to inundation is proposed to support decision-making and to maximise the benefits of environmental flow regimes for floodplain lakes
Dispersion insensitive, high-speed optical clock recovery based on a mode-locked laser diode
An investigation into the effects of varying levels of chromatic dispersion on a mode- locked laser diode optical clock recovery process is presented. Results demonstrate that this technique is invariant to input dispersion varying between +75 ps/nm
A comparative study of Type II-P and II-L supernova rise times as exemplified by the case of LSQ13cuw
We report on our findings based on the analysis of observations of the Type
II-L supernova LSQ13cuw within the framework of currently accepted physical
predictions of core-collapse supernova explosions. LSQ13cuw was discovered
within a day of explosion, hitherto unprecedented for Type II-L supernovae.
This motivated a comparative study of Type II-P and II-L supernovae with
relatively well-constrained explosion epochs and rise times to maximum
(optical) light. From our sample of twenty such events, we find evidence of a
positive correlation between the duration of the rise and the peak brightness.
On average, SNe II-L tend to have brighter peak magnitudes and longer rise
times than SNe II-P. However, this difference is clearest only at the extreme
ends of the rise time versus peak brightness relation. Using two different
analytical models, we performed a parameter study to investigate the physical
parameters that control the rise time behaviour. In general, the models
qualitatively reproduce aspects of the observed trends. We find that the
brightness of the optical peak increases for larger progenitor radii and
explosion energies, and decreases for larger masses. The dependence of the rise
time on mass and explosion energy is smaller than the dependence on the
progenitor radius. We find no evidence that the progenitors of SNe II-L have
significantly smaller radii than those of SNe II-P.Comment: 19 pages, 10 figures, accepted by A&
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