397 research outputs found
Industrial work placement in higher education: a study of civil engineering student engagement
For civil engineering undergraduates, the opportunity to spend a period of time in formal industrial work placement provides an invaluable learning experience. This paper reviews student engagement with short-term industrial placement and provides analysis of questionnaires (n=174) returned by undergraduates studying civil engineering at four Higher Education Institutes (HEI’s) in the West of Scotland. The data captures industrial placement statistics, employability skill-sets and presents brief testimonies from students. Whilst the journey to becoming a professional civil engineer is undoubtedly enhanced by short-term placement clear opportunities exist for HEI’s to affect and change existing pedagogical discourse. Commentary is likely to resonate beyond civil engineering and serve as a timely reminder of the need to re-invigorate academia / industry curriculum partnerships
Structure-based design and synthesis of antiparasitic pyrrolopyrimidines targeting pteridine reductase 1
The treatment of Human African Trypanosomiasis remains a major unmet health need in sub-Saharan Africa. Approaches involving new molecular targets are important and pteridine reductase 1 (PTR1), an enzyme that reduces dihydrobiopterin in Trypanosoma spp. has been identified as a candidate target and it has been shown previously that substituted pyrrolo[2,3-d]pyrimidines are inhibitors of PTR1 from T. brucei (J. Med. Chem. 2010, 53, 221-229). In this study, 61 new pyrrolo[2,3-d]pyrimidines have been prepared, designed with input from new crystal structures of 23 of these compounds complexed with PTR1, and evaluated in screens for enzyme inhibitory activity against PTR1 and in vitro antitrypanosomal activity. 8 compounds were sufficiently active in both screens to take forward to in vivo evaluation. Thus although evidence for trypanocidal activity in a stage I disease model in mice was obtained, the compounds were too toxic to mice for further development
Proton acceleration by irradiation of isolated spheres with an intense laser pulse
We report on experiments irradiating isolated plastic spheres with a peak laser intensity of 2-3 x 10(20) W cm(-2). With a laser focal spot size of 10 mu m full width half maximum (FWHM) the sphere diameter was varied between 520 nm and 19.3 mu m. Maximum proton energies of similar to 25 MeV are achieved for targets matching the focal spot size of 10 mu m in diameter or being slightly smaller. For smaller spheres the kinetic energy distributions of protons become nonmonotonic, indicating a change in the accelerating mechanism from ambipolar expansion towards a regime dominated by effects caused by Coulomb repulsion of ions. The energy conversion efficiency from laser energy to proton kinetic energy is optimized when the target diameter matches the laser focal spot size with efficiencies reaching the percent level. The change of proton acceleration efficiency with target size can be attributed to the reduced cross-sectional overlap of subfocus targets with the laser. Reported experimental observations are in line with 3D3V particle in cell simulations. They make use of well-defined targets and point out pathways for future applications and experiments.DFG via the Cluster of Excellence Munich-Centre for Advanced Photonics (MAP) Transregio SFB TR18NNSA DE-NA0002008Super-MUC pr48meIvo CermakCGC Instruments in design and realization of the Paul trap systemIMPRS-APSLMUexcellent Junior Research FundDAAD|ToIFEEuropean Union's Horizon research and innovation programme 633053Physic
Emerging nuclear collectivity in Te
The emergence of nuclear collectivity near doubly-magic Sn was
explored along the stable, even-even Te isotopes. Preliminary
measurements of the transition strengths
are reported from Coulomb excitation experiments primarily aimed at measuring
the factors of the states. Isotopically enriched Te targets
were excited by 198-205 MeV Ni beams. A comparison of transition
strengths obtained is made to large-scale shell-model calculations with
successes and limitations discussed.Comment: 5 pages, 3 figures, Submitted to Proceedings HIAS 2019, EPJ Web of
Conference
Shape polarization in the tin isotopes near from precision -factor measurements on short-lived isomers
The factors of isomers in semimagic Sn and Sn
(isomeric lifetimes ns and ns, respectively)
were measured by an extension of the Time Differential Perturbed Angular
Distribution technique, which uses \LaBr detectors and the hyperfine fields of
a gadolinium host to achieve precise measurements in a new regime of
short-lived isomers. The results,
and , are significantly lower in
magnitude than those of the isomers in the heavier isotopes and depart
from the value expected for a near pure neutron configuration.
Broken-symmetry density functional theory calculations applied to the sequence
of states reproduce the magnitude and location of this deviation. The
values are affected by shape core polarization; the odd
neutron couples to configurations in the
weakly-deformed effective core, causing a decrease in the -factor
magnitudes.Comment: 8 pages, 7 figures. Accepted in Physics Letters
Evidence for shape coexistence and superdeformation in 24Mg
The E0 transition depopulating the first-excited 0+ state in 24Mg has been observed for the first time, and the E0 transition strength determined by electron-positron pair and γ-ray spectroscopy measurements performed using the Super-e pair spectrometer. The E0 transition strength is ρ2×103=380(70). A two-state mixing model implies a deformation of the first-excited 0+ state of β2≈1 and a change in the mean-square charge radius of Δ〈r2〉≈1.9fm2, which suggests a significant shape change between the ground state and first-excited 0+ state in 24Mg. The observed E0 strength gives direct evidence of shape coexistence and superdeformation in 24Mg, bringing this nucleus into line with similar behaviour in nearby N=Z nuclei. This result agrees with recent theoretical work on the cluster nature of 24Mg and has potential ramifications for nuclear reactions of astrophysical importance
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