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The class novel in first and second year mixed ability classes
There is conflicting evidence on the extent and value of using the class novel in English classrooms, particularly in the first two years of secondary school. This study looks at the literature on this subject over the last eighty years or so and discovers that it is inconclusive and deficient in certain respects.
A new survey was therefore set up involving teachers of English in one division of Strathclyde - Lanark. The design, piloting and issue of the questionnaire used in the survey is explained in detail.
The questionnaire focused on certain key issues such as the prevalence of the use of the class novel, its relative importance in the English curriculum of first and second years Cas compared with other components of the English curriculum such as poetry and drama), the reasons that teachers gave for using it, the methods of reading they employ and the problems that its use poses for the teacher of a mixed ability class.
A full report of the survey's Findings is given. Some of the key findings are that contrary to the frequently expressed view in 'official' reports over the years, the class novel is considered by large numbers of teachers of English to be the most important component of their courses in both first and second years; that there is a great reliance on reading aloud in class as a method of reading and that there are practical problems associated with its use in the mixed ability class when there are numbers of pupils unable to cope with reading the class novel unaided. Some light is thrown on the types of assignments that teachers set once the novel has been read where the survey discovers that two types of assignment dominate work on the class novel - questions on the novel’s storyline and assignments using the novel as stimulus for personal / creative writing.
The findings are discussed in some detail in relation to literature in the field and also in relation to traditionally held theories about what the nature of English teaching should be.
Unresolved issues are identified such as the effect that type of class might have on the decision to use a class novel and on the method of reading it; the use of the novel in the year(s) immediately prior to the secondary school in primary and its use in the later years of secondary school. In the light of these, suggestions are made for future research and some attempt is made at evaluating the practical implications of this study for current practice
Structural and spectroscopic characterisation of C4 oxygenates relevant to structure/activity relationships of the hydrogenation of α,β-unsaturated carbonyls
In the present work, we have investigated the conformational isomerism and calculated the vibrational spectra of the C4 oxygenates: 3-butyne-2-one, 3-butene-2-one, 2-butanone and 2-butanol using density functional theory. The calculations are validated by comparison to structural data where available and new, experimental inelastic neutron scattering and infrared spectra of the compounds. We find that for 3-butene-2-one and 2-butanol the spectra show clear evidence for the presence of conformational isomerism and this is supported by the calculations. Complete vibrational assignments for all four molecules are provided and this provides the essential information needed to generate structure/activity relationships for the sequential catalytic hydrogenation of 3-butyne-2-one to 2-butanol
Rotational Mixing in Magellanic Clouds B Stars - Theory versus Observation
We have used VLT FLAMES data to constrain the uncertain physics of rotational
mixing in stellar evolution models. We have simulated a population of single
stars and find two groups of observed stars that cannot be explained: (1) a
group of fast rotating stars which do not show evidence for rotational mixing
and (2) a group of slow rotators with strong N enrichment. Binary effects and
fossil magnetic fields may be considered to explain those two groups. We
suggest that the element boron could be used to distinguish between rotational
mixing and the binary scenario. Our single star population simulations quantify
the expected amount of boron in fast and slow rotators and allow a comparison
with measured nitrogen and boron abundances in B-stars.Comment: to appear in Comm. in Astroseismology - Contribution to the
Proceedings of the 38th LIAC, 200
A census of massive stars in NGC 346. Stellar parameters and rotational velocities
Spectroscopy for 247 stars towards the young cluster NGC 346 in the Small
Magellanic Cloud has been combined with that for 116 targets from the
VLT-FLAMES Survey of Massive Stars. Spectral classification yields a sample of
47 O-type and 287 B-type spectra, while radial-velocity variations and/or
spectral multiplicity have been used to identify 45 candidate single-lined
systems, 17 double-lined systems, and one triple-lined system. Atmospheric
parameters (T and log) and projected rotational velocities
(sin) have been estimated using TLUSTY model atmospheres; independent
estimates of sin were also obtained using a Fourier Transform method.
Luminosities have been inferred from stellar apparent magnitudes and used in
conjunction with the T and sin estimates to constrain stellar
masses and ages using the BONNSAI package. We find that targets towards the
inner region of NGC 346 have higher median masses and projected rotational
velocities, together with smaller median ages than the rest of the sample.
There appears to be a population of very young targets with ages of less than 2
Myr, which have presumably all formed within the cluster. The more massive
targets are found to have lower sin consistent with previous studies.
No significant evidence is found for differences with metallicity in the
stellar rotational velocities of early-type stars, although the targets in the
SMC may rotate faster than those in young Galactic clusters. The rotational
velocity distribution for single non-supergiant B-type stars is inferred and
implies that a significant number have low rotational velocity (10\%
with <40 km/s), together with a peak in the probability distribution at
300 km/s. Larger projected rotational velocity estimates have been
found for our Be-type sample and imply that most have rotational velocities
between 200-450 km/s.Comment: Accepted by A&
Chemical abundances and winds of massive stars in M31: a B-type supergiant and a WC star in OB10
We present high quality spectroscopic data for two massive stars in the OB10
association of M31, OB10-64 (B0Ia) and OB10-WR1 (WC6). Medium resolution
spectra of both stars were obtained using the ISIS spectrograph on the William
Hershel Telescope. This is supplemented with HST-STIS UV spectroscopy and KeckI
HIRES data for OB10-64. A non-LTE model atmosphere and abundance analysis for
OB10-64 is presented indicating that this star has similar photospheric CNO, Mg
and Si abundances as solar neighbourhood massive stars. A wind analysis of this
early B-type supergiant reveals a mass-loss rate of M_dot=1.6x10^-6
M_solar/yr,and v_infty=1650 km/s. The corresponding wind momentum is in good
agreement with the wind momentum -- luminosity relationship found for Galactic
early B supergiants. Observations of OB10W-R1 are analysed using a non-LTE,
line-blanketed code, to reveal approximate stellar parameters of log L/L_solar
\~ 5.7, T~75 kK, v_infty ~ 3000 km/s, M_dot ~ 10^-4.3 M_solar/yr, adopting a
clumped wind with a filling factor of 10%. Quantitative comparisons are made
with the Galactic WC6 star HD92809 (WR23) revealing that OB10-WR1 is 0.4 dex
more luminous, though it has a much lower C/He ratio (~0.1 versus 0.3 for
HD92809). Our study represents the first detailed, chemical model atmosphere
analysis for either a B-type supergiant or a WR star in Andromeda, and shows
the potential of how such studies can provide new information on the chemical
evolution of galaxies and the evolution of massive stars in the local Universe.Comment: 17 pages, 14 figures, MNRAS accepted version, some minor revision
A Be star with a low nitrogen abundance in the SMC cluster NGC330
High-resolution UVES/VLT spectra of B12, an extreme pole-on Be star in the
SMC cluster NGC330, have been analysed using non-LTE model atmospheres to
obtain its chemical composition relative to the SMC standard star AV304. We
find a general underabundance of metals which can be understood in terms of an
extra contribution to the stellar continuum due to emission from a disk which
we estimate to be at the ~25% level. When this is corrected for, the nitrogen
abundance for B12 shows no evidence of enhancement by rotational mixing as has
been found in other non-Be B-type stars in NGC330, and is inconsistent with
evolutionary models which include the effects of rotational mixing. A second Be
star, NGC330-B17, is also shown to have no detectable nitrogen lines. Possible
explanations for the lack of rotational mixing in these rapidly rotating stars
are discussed, one promising solution being the possibility that magnetic
fields might inhibit rotational mixing.Comment: 7 pages, 4 figures. Submitted to A&
C II abundances in early-type stars: solution to a notorious non-LTE problem
We address a long-standing discrepancy between non-LTE analyses of the
prominent C II 4267 and 6578/82 A multiplets in early-type stars. A
comprehensive non-LTE model atom of C II is constructed based on critically
selected atomic data. This model atom is used for an abundance study of six
apparently slow-rotating main-sequence and giant early B-type stars.
High-resolution and high-S/N spectra allow us to derive highly consistent
abundances not only from the classical features but also from up to 18 further
C II lines in the visual - including two so far unreported emission features
equally well reproduced in non-LTE. These results require the stellar
atmospheric parameters to be determined with care. A homogeneous (slightly)
sub-solar present-day carbon abundance from young stars in the solar vicinity
(in associations and in the field) of log C/H +12= 8.29+/-0.03 is indicated.Comment: 8 pages, 5 figure
Gaia TGAS search for Large Magellanic Cloud runaway supergiant stars:Candidate hypervelocity star discovery, and the nature of R71
We search for runaway stars in the Large Magellanic Cloud (LMC) by computing
the space velocities of the visually brightest stars in the LMC that are
included in the Gaia TGAS proper motion catalog. We compare with predictions
from stellar dynamical models to obtain (peculiar) velocities relative to their
local stellar environment. Two of the 31 stars have unusually high proper
motions. Of the remaining 29 stars we find that most objects in this sample
have velocities in very good agreement with model predictions of a circularly
rotating disk model. Indeed the excellent fit to the model implies that the
TGAS uncertainty estimates are likely overestimated. The fastest outliers in
this subsample contain the LBV R71 and a few other well known emission line
objects though in no case do we derive velocities consistent with fast (~100
km/s) runaways. Our results imply that R 71 in particular has a moderate
deviation from the local stellar velocity field (40 km/s) lending support to
the proposition that this object cannot have evolved as a normal single star
since it lies too far from massive star forming complexes to have arrived at
its current position during its lifetime. Our findings therefore strengthen the
case for this LBV being the result of binary evolution. Of the two stars with
unusually high proper motions we find that one, the isolated B1.5 Ia+
supergiant Sk-67 2 (HIP 22237), is a candidate hypervelocity star, the TGAS
proper motion implying a very large peculiar transverse velocity (~360 km/s)
directed radially away from the LMC centre. If confirmed, for example by Gaia
Data Release 2, it would imply that this massive supergiant, on the periphery
of the LMC, is leaving the galaxy where it will explode as a supernova.Comment: 7 pages, 5 figures, revised versio
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