1,154 research outputs found
Reliability of ultrasound strain elastography in the assessment of the quadriceps and patellar tendon in healthy adults
Are UK medical schools using recommended national curricula for the teaching of clinical neuroscience?
Background: Medical schools are responsible for training medical students to recognise and commence management for a broad spectrum of diseases, including clinical neuroscience conditions. To guide medical schools on important topics, speciality bodies have produced speciality-based core curricula. It is unknown to what extent these guidelines are used in medical school curriculum design. We aimed to assess the use of these guidelines in designing clinical neuroscience curricula.
Methods: This is a national survey. A 21-item questionnaire was sent to faculty members involved in the development of the clinical neuroscience curriculum in each medical school in the UK. The Association of British Neurologists (ABN) and the Royal College of Surgeons England (RCSEng) guidelines were used as a benchmark. Descriptive statistics are reported.
Results: Data was collected from 34 UK medical schools (91.9% of those eligible). 61.8% of respondents were aware of ABN guidelines and 35.3% were aware of RCSEng guidelines. Only 23.5% of medical schools taught all 28 recommended neuroscience topics, and were not more likely to be those that used national guidelines (χ2=1.25-31, p=0.99). Furthermore, 97.1% said that they would use national guidance when making further developments to their curriculum. Neurologists were involved in the design of the clinical neuroscience curriculum in 94.1% of medical schools, and neurosurgeons in 61.8%. Tutorials/seminars were used by all medical schools to teach clinical neuroscience content. Neurologists were involved in teaching at all schools and neurosurgeons in 70.6%. Objective Structured Clinical Examinations and single best answer/multiple-choice question tests were used in all medical schools for assessment.
Conclusions: There is variation between medical schools on what clinical neuroscience topics are taught and by whom. Multi-modality educational delivery was evident. Some medical schools did not currently use or recommend external clinical neuroscience educational resources; but there is support for future use of external resources including guidelines
Noise auto-correlation spectroscopy with coherent Raman scattering
Ultrafast lasers have become one of the most powerful tools in coherent
nonlinear optical spectroscopy. Short pulses enable direct observation of fast
molecular dynamics, whereas broad spectral bandwidth offers ways of controlling
nonlinear optical processes by means of quantum interferences. Special care is
usually taken to preserve the coherence of laser pulses as it determines the
accuracy of a spectroscopic measurement. Here we present a new approach to
coherent Raman spectroscopy based on deliberately introduced noise, which
increases the spectral resolution, robustness and efficiency. We probe laser
induced molecular vibrations using a broadband laser pulse with intentionally
randomized amplitude and phase. The vibrational resonances result in and are
identified through the appearance of intensity correlations in the noisy
spectrum of coherently scattered photons. Spectral resolution is neither
limited by the pulse bandwidth, nor sensitive to the quality of the temporal
and spectral profile of the pulses. This is particularly attractive for the
applications in microscopy, biological imaging and remote sensing, where
dispersion and scattering properties of the medium often undermine the
applicability of ultrafast lasers. The proposed method combines the efficiency
and resolution of a coherent process with the robustness of incoherent light.
As we demonstrate here, it can be implemented by simply destroying the
coherence of a laser pulse, and without any elaborate temporal scanning or
spectral shaping commonly required by the frequency-resolved spectroscopic
methods with ultrashort pulses.Comment: To appear in Nature Physic
Quantum correlations between a pair of Raman photons from a single atom under arbitrary excitation condition
The quantum correlation between a pair of Stokes and anti-Stokes photons, involving a Raman emission process is calculated. All realistic radiative and nonradiative decays are included in the calculation and the photon correlation between the pair for arbitrarily strong excitation fields and detunings are calculated. The correlation function shows photon antibunching, and a damped sinusoidal behavior with respect to the time delay between the measurement of the two photons. The current system can also produce four photon entanglement
Pressure Dependence of the Irreversibility Line in BiSrCaCuO:Role of Anisotropy in Flux-Line Formation
One of the important problems of high-temperature superconductivity is to
understand and ultimately to control fluxoid motion. We present the results of
a new technique for measuring the pressure dependence of the transition to
superconductivity in a diamond anvil cell. By measuring the third harmonic of
the {\it ac} susceptibility, we determine the onset of irreversible flux
motion. This enables us to study the effects of pressure on flux motion. The
application of pressure changes interplanar spacing, and hence the interplanar
coupling, without significantly disturbing the intraplanar superconductivity.
Thus we are able to separate the effects of coupling from other properties that
might affect the flux motion. Our results directly show the relationship
between lattice spacing, effective- mass anisotropy, and the irreversibility
line in BiSrCaCuO. Our results also demonstrate
that an application of 2.5 GPa pressure causes a dramatic increase in
interplanar coupling.Comment: 4 pages, 4 figure
Cyproterone acetate or spironolactone in lowering testosterone concentrations for transgender individuals receiving oestradiol therapy
BACKGROUND:Estradiol with or without an antiandrogen (cyproterone acetate or spironolactone) is commonly prescribed in transfeminine individuals who have not had orchidectomy, however there is no evidence to guide optimal treatment choice. OBJECTIVE:We aimed to compare add-on cyproterone acetate versus spironolactone in lowering endogenous testosterone concentrations in transfeminine individuals. DESIGN:Retrospective cross-sectional study. METHODS:We analysed 114 transfeminine individuals who had been on estradiol therapy for >6 months in two gender clinics in Melbourne, Australia. Total testosterone concentrations were compared between three groups; estradiol alone (n=21), estradiol plus cyproterone acetate (n=21) and estradiol plus spironolactone (n=38). Secondary outcomes included serum estradiol concentration, estradiol valerate dose, blood pressure, serum potassium, urea and creatinine. RESULTS:Median age was 27.0 years (22.5, 45.1) and median duration of hormone therapy was 1.5 years (0.9, 2.6), which was not different between groups. On univariate analysis, the cyproterone group had significantly lower total testosterone concentrations (0.8nmol/L (0.6, 1.20)) compared with the spironolactone group (2.0nmol/L (0.9, 9.4), p=0.037) and estradiol alone group (10.5nmol/L (4.9, 17.2), p<0.001), which remained significant (p=0.005) after adjustments for estradiol concentration, dose and age. Serum urea was higher in the spironolactone group compared with the cyproterone group. No differences were observed in total daily estradiol dose, blood pressure, serum estradiol, potassium or creatinine. CONCLUSIONS:The cyproterone group achieved serum total testosterone concentrations in the female reference range. As spironolactone may cause feminisation without inhibition of steroidogenesis, it is unclear which anti-androgen is more effective at feminisation. Further prospective studies are required.Lachlan Angus, Shalem Leemaqz, Olivia Ooi, Pauline Cundill, Nicholas Silberstein, Peter Locke, Jeffrey D Zajac and Ada S Cheun
Intracellular interferons in fish : a unique means to combat viral infection
Peer reviewedPublisher PD
Epidemiological risk factors for adult dengue in Singapore: an 8-year nested test negative case control study
10.1186/s12879-016-1662-4BMC Infectious Diseases16132
Graphite and Hexagonal Boron-Nitride Possess the Same Interlayer Distance. Why?
Graphite and hexagonal boron nitride (h-BN) are two prominent members of the
family of layered materials possessing a hexagonal lattice. While graphite has
non-polar homo-nuclear C-C intra-layer bonds, h-BN presents highly polar B-N
bonds resulting in different optimal stacking modes of the two materials in
bulk form. Furthermore, the static polarizabilities of the constituent atoms
considerably differ from each other suggesting large differences in the
dispersive component of the interlayer bonding. Despite these major differences
both materials present practically identical interlayer distances. To
understand this finding, a comparative study of the nature of the interlayer
bonding in both materials is presented. A full lattice sum of the interactions
between the partially charged atomic centers in h-BN results in vanishingly
small monopolar electrostatic contributions to the interlayer binding energy.
Higher order electrostatic multipoles, exchange, and short-range correlation
contributions are found to be very similar in both materials and to almost
completely cancel out by the Pauli repulsions at physically relevant interlayer
distances resulting in a marginal effective contribution to the interlayer
binding. Further analysis of the dispersive energy term reveals that despite
the large differences in the individual atomic polarizabilities the
hetero-atomic B-N C6 coefficient is very similar to the homo-atomic C-C
coefficient in the hexagonal bulk form resulting in very similar dispersive
contribution to the interlayer binding. The overall binding energy curves of
both materials are thus very similar predicting practically the same interlayer
distance and very similar binding energies.Comment: 18 pages, 5 figures, 2 table
Experiments in vortex avalanches
Avalanche dynamics is found in many phenomena spanning from earthquakes to
the evolution of species. It can be also found in vortex matter when a type II
superconductor is externally driven, for example, by increasing the magnetic
field. Vortex avalanches associated with thermal instabilities can be an
undesirable effect for applications, but "dynamically driven" avalanches
emerging from the competition between intervortex interactions and quenched
disorder constitute an interesting scenario to test theoretical ideas related
with non-equilibrium dynamics. However, differently from the equilibrium phases
of vortex matter in type II superconductors, the study of the corresponding
dynamical phases - in which avalanches can play a role - is still in its
infancy. In this paper we critically review relevant experiments performed in
the last decade or so, emphasizing the ability of different experimental
techniques to establish the nature and statistical properties of the observed
avalanche behavior.Comment: To be published in Reviews of Modern Physics April 2004. 17 page
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