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Engaging with economic geography in the "real" world: a central role for field teaching
Debates concerning how to engage students with economic geography have ignored the important role of field teaching. This paper argues that fieldwork must remain a key component of economic geographical teaching and that it offers a variety of advantages to overcoming student disinterest in the sub-discipline. It goes on to argue that field teaching must be developed, not neglected, in economic geography and illustrates its pedagogical advantages with reference to the example of a field class in north-east England
Is there an Economic Case for the Olympic Games?
The Olympic Games are a major undertaking that promise both large costs and potentially large benefits to host cities. This paper lays out the potential economic benefits of hosting the Olympics and details how, in the vast majority of cases, these gains are unlikely to cover the costs of hosting the event. The ideas are then applied to the experience of Boston in its ultimately unsuccessful bid for the 2024 Summer Olympics
Charge pair dissociation and recombination dynamics in a P3HT–PC60BM bulk heterojunction
The authors thank the EPSRC, SUPA, the Condensed Matter Doctoral Training Centre and the European Union Seventh Framework programme (grant agreement 321305) for financial support.The mechanism by which Coulombically bound charge pairs dissociate into free carriers in photovoltaic donor–acceptor blends is of great interest. Here, we use polarization-sensitive transient absorption (TA) to study the diffusion of photogenerated holes in a polythiophene (P3HT)–fullerene (PC60BM) blend. We observe an initial anisotropy value of 0.4 for the absorption of photogenerated holes, indicating that holes generated on a 100 fs time scale are localized on the same polymer chain as their precursor excitons. Depolarization dynamics indicate fast initial hole motion on a 0.3 ps time scale and slower migration up to 100 ps. Charge pair recombination is found to occur on a much longer time scale of 10–1000 ns via a purely bimolecular process independent of excess energy. Our results show that nearly all charge pairs get separated by at least 7 nm in the absence of an external field and indicate that high charge mobility is crucial for charge separation.PostprintPeer reviewe
Type II Supernova Light Curves and Spectra From the CfA
We present multiband photometry of 60 spectroscopically-confirmed supernovae
(SN): 39 SN II/IIP, 19 IIn, one IIb and one that was originally classified as a
IIn but later as a Ibn. Forty-six have only optical photometry, six have only
near infrared (NIR) photometry and eight have both optical and NIR. The median
redshift of the sample is 0.016. We also present 192 optical spectra for 47 of
the 60 SN. All data are publicly available. There are 26 optical and two NIR
light curves of SN II/IIP with redshifts z > 0.01, some of which may give rise
to useful distances for cosmological applications. All photometry was obtained
between 2000 and 2011 at the Fred Lawrence Whipple Observatory (FLWO), via the
1.2m and 1.3m PAIRITEL telescopes for the optical and NIR, respectively. Each
SN was observed in a subset of the bands. There are a total
of 2932 optical and 816 NIR light curve points. Optical spectra were obtained
using the FLWO 1.5m Tillinghast telescope with the FAST spectrograph and the
MMT Telescope with the Blue Channel Spectrograph. Our photometry is in
reasonable agreement with other samples from the literature. Comparison with
Pan-STARRS shows that two-thirds of our individual star sequences have
weighted-mean V offsets within 0.02 mag. In comparing our standard-system
SN light curves with common Carnegie Supernova Project objects using their
color terms, we found that roughly three-quarters have average differences
within 0.04 mag. The data from this work and the literature will provide
insight into SN II explosions, help with developing methods for photometric SN
classification, and contribute to their use as cosmological distance
indicators.Comment: Accepted to ApJS. TAR of light curves and star sequences here:
https://www.cfa.harvard.edu/supernova/fmalcolm2017/cfa_snII_lightcurvesndstars.june2017.tar
... Spectra can be found here:
https://www.cfa.harvard.edu/supernova/fmalcolm2017/cfaspec_snII.tar.gz ...
Passbands and plot of spectra can be found here:
https://www.cfa.harvard.edu/supernova/SNarchive.htm
Stable emulsions of droplets in a solid edible organogel matrix
Sitosterol–oryzanol organogels are unstable near water, but are shown to be stable in the presence of glycerol.</p
Dismantling the present and future threats of testicular cancer: a grounded theory of positive and negative adjustment trajectories
Testicular cancer commonly affects men in the prime of their lives. While survival rates are excellent, little previous research has examined men’s experiences of adjustment to survivorship. We aimed to explore this issue in younger testicular cancer survivors
Reducing drug related deaths : a pre-implementation assessment of knowledge,barriers and enablers for naloxone distribution through general practice
Peer reviewedPublisher PD
Combined fluorescence lifetime and surface topographical imaging of biological tissue
In this work a combined fluorescence lifetime and surface topographical imaging system is demonstrated. Based around a 126 × 192 time resolved single photon avalanche diode (SPAD) array operating in time correlated single-photon counting (TCSPC) mode, both the fluorescence lifetime and time of flight (ToF) can be calculated on a pixel by pixel basis. Initial tests on fluorescent samples show it is able to provide 4 mm resolution in distance and 0.4 ns resolution in lifetime. This combined modality has potential biomedical applications such as surgical guidance, endoscopy and diagnostic imaging. The system is demonstrated on both ovine and human pulmonary tissue samples, where it offers excellent fluorescence lifetime contrast whilst also giving a measure of the distance to the sample surfac
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