112 research outputs found
Possibility of Macroscopic resonant Tunneling near the Superconductor- Insulator Transition in YBaCuO Thin Films
Experimental results of I-V characteristics near the superconductor-insulator
transition observed for disorder-tuned YBaCuO thinfilms are presented. The I-V
characteristics exibit new quasiperiodic structures as a function of the
current. The current interval, the number of the dI/dV peaks, and the magnetic
field dependence of the peaks are consistent with the theoretical predictions
of the resonant tunneling of a phase particle ina tilted-cosine potential for
asingle Josephson junction with small capacitance.Comment: 7 pages, 4 figures, in press (Europhys. Lett.
Developing strategies for university, industry, and government partnership in Indonesia
The Government of Indonesia has launched an ambitious Master Plan for Acceleration and Expansion of Indonesia Economic Development or MP3EI, with a view to promoting geographically dispersed growth through establishing seven economic corridors across the nation. The objective of this study is to review the current status of universities in Indonesia in terms of their capacity to work in partnership with industry and government. The review will assess whether they can contribute to the realization of such a vision, and it will make recommendations about future strategies and actions. The study was commissioned by the Ministry of National Planning (BAPPENAS) and the Ministry of Education and Culture through the Analytical and Capacity Development Partnership (ACDP) program, which is funded by the European Union and the Australian-AID and administered by the Asian Development Bank (ADB)
Topologically Linked Crystals
We discovered a new class of topological crystals, namely linked rings of
crystals. Two rings of tantalum triselenide (TaSe3) single crystals were linked
to each other while crystal growing. The topology of the crystal form is called
a "Hopf link", which is the simplest link involving just two component unknots
linked together exactly once. The feature of the crystals is not covered by the
conventional crystallography.Comment: 6 pages, 3 figures, to appear in J. Crystal Growt
Pinhole calculations of the Josephson effect in 3He-B
We study theoretically the dc Josephson effect between two volumes of
superfluid 3He-B. We first discuss how the calculation of the current-phase
relationships is divided into a mesoscopic and a macroscopic problem. We then
analyze mass and spin currents and the symmetry of weak links. In quantitative
calculations the weak link is assumed to be a pinhole, whose size is small in
comparison to the coherence length. We derive a quasiclassical expression for
the coupling energy of a pinhole, allowing also for scattering in the hole.
Using a selfconsistent order parameter near a wall, we calculate the
current-phase relationships in several cases. In the isotextural case, the
current-phase relations are plotted assuming a constant spin-orbit texture. In
the opposite anisotextural case the texture changes as a function of the phase
difference. For that we have to consider the stiffness of the macroscopic
texture, and we also calculate some surface interaction parameters. We analyze
the experiments by Marchenkov et al. We find that the observed pi states and
bistability hardly can be explained with the isotextural pinhole model, but a
good quantitative agreement is achieved with the anisotextural model.Comment: 20 pages, 21 figures, revtex
Interaction Properties of the Periodic and Step-like Solutions of the Double-Sine-Gordon Equation
The periodic and step-like solutions of the double-Sine-Gordon equation are
investigated, with different initial conditions and for various values of the
potential parameter . We plot energy and force diagrams, as functions
of the inter-soliton distance for such solutions. This allows us to consider
our system as an interacting many-body system in 1+1 dimension. We therefore
plot state diagrams (pressure vs. average density) for step-like as well as
periodic solutions. Step-like solutions are shown to behave similarly to their
counterparts in the Sine-Gordon system. However, periodic solutions show a
fundamentally different behavior as the parameter is increased. We
show that two distinct phases of periodic solutions exist which exhibit
manifestly different behavior. Response functions for these phases are shown to
behave differently, joining at an apparent phase transition point.Comment: 17pages, 15 figure
Local Inhomogeneity Effects on Nucleation Process in a High External Bias
Quantum nucleation processes in the presence of local moderate
inhomogeneities are studied theoretically at high biases. The quantum
nucleation rate Gamma is calculated for one-dimensional systems in a form Gamma
= A e^(-B/hbar) by using the `bounce' method. The bias-dependence of the
exponent B is shown to be changed by inhomogeneities. This change is explained
by the reduction of the effective spatial dimension of the system. By studying
the system-size dependence of the prefactor A, the condition for the appearance
of inhomogeneity effects is evaluated. Nucleation rates in thermal activation
regimes are also calculated, and compared with quantum tunneling regimes. For
higher-dimensional systems, it is shown that the local approximation of
inhomogeneity does not hold, and that spatial profiles of inhomogeneity become
important.Comment: 10 pages, 6 figure
Josephson Effect between Condensates with Different Internal Structures
A general formula for Josephson current in a wide class of hybrid junctions
between different internal structures is derived on the basis of the Andreev
picture. The formula extends existing formulae and also enables us to analyze
novel B-phase/A-phase/B-phase (BAB) junctions in superfluid helium three
systems, which are accessible to experiments. It is predicted that BAB
junctions will exhibit two types of current-phase relations associated with
different internal symmetries. A ``pseudo-magnetic interface effect'' inherent
in the system is also revealed.Comment: 4 pages, 2 figure
Indicators of universityâindustry knowledge transfer performance and their implication for universities: evidence from the United Kingdom
The issue of what indicators are most appropriate in order to measure the performance of universities in knowledge transfer (KT) activities remains relatively under-investigated. The main aim of this paper is to identify and discuss the limitations to the current measurements of university-industry KT performance, and propose some directions for improvement. We argue that university-industry KT can unfold in many ways and impact many stakeholders, and that, especially in highly differentiated university systems, choosing indicators focused on a narrow range of activities and impacts might limit the ability of universities to accurately represent their KT performance. Therefore, KT indicators should include a variety of activities and reflect a variety of impacts, so as to allow comparability between different institutions and avoid the creation of undesirable behavioural incentives. To illustrate these issues empirically, we discuss the case of the United Kingdomâs Higher Education âBusiness and Community Interaction (HE-BCI) survey
Alterations in anatomic and functional imaging parameters with repeated FDG PET-CT and MRI during radiotherapy for head and neck cancer: a pilot study
Background: The use of imaging to implement on-treatment adaptation of radiotherapy is a promising paradigm but current data on imaging changes during radiotherapy is limited. This is a hypothesis-generating pilot study to examine the changes on multi-modality anatomic and functional imaging during (chemo)radiotherapy treatment for head and neck squamous cell carcinoma (HNSCC). Methods: Eight patients with locally advanced HNSCC underwent imaging including computed tomography (CT), Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)-CT and magnetic resonance imaging (MRI) (including diffusion weighted (DW) and dynamic contrast enhanced (DCE)) at baseline and during (chemo)radiotherapy treatment (after fractions 11 and 21). Regions of interest (ROI) were drawn around the primary tumour at baseline and during treatment. Imaging parameters included gross tumour volume (GTV) assessment, SUVmax, mean ADC value and DCE-MRI parameters including Plasma Flow (PF). On treatment changes and correlations between these parameters were analysed using a Wilcoxon rank sum test and Pearsonâs linear correlation coefficient respectively. A p-value <0.05 was considered statistically significant. Results: Statistically significant reductions in GTV-CT, GTV-MRI and GTV-DW were observed between all imaging timepoints during radiotherapy. Changes in GTV-PET during radiotherapy were heterogeneous and non-significant. Significant changes in SUVmax, mean ADC value, Plasma Flow and Plasma Volume were observed between the baseline and the fraction 11 timepoint, whilst only changes in SUVmax between baseline and the fraction 21 timepoint were statistically significant. Significant correlations were observed between multiple imaging parameters, both anatomical and functional; 20 correlations between baseline to the fraction 11 timepoint; 12 correlations between baseline and the fraction 21 timepoints; and 4 correlations between the fraction 11 and fraction 21 timepoints. Conclusions: Multi-modality imaging during radiotherapy treatment demonstrates early changes (by fraction 11) in both anatomic and functional imaging parameters. All functional imaging modalities are potentially complementary and should be considered in combination to provide multi-parametric tumour assessment, to guide potential treatment adaptation strategies. Trial Registration: ISRCTN Registry: ISRCTN34165059. Registered 2nd February 2015
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