3,391 research outputs found
The importance of scientific competencies in German medical curricula - the student perspective
Background: Scientific competencies are of great importance for physicians; not only for conducting reliable research, but also for patient care. However, there is growing concern that a lack of scientific competencies among physicians may lead to a deterioration in the quality on biomedical research. This study aims at assessing medical students’ perspectives on the implementation of scientific competency training in German medical curricula.
Methods: An online survey was conducted in order to collect German medical students’ opinions on the importance of acquiring scientific competencies during their medical studies and to provide us with an assessment of their current levels of basic scientific competencies by having them conduct a self-evaluation. Moreover, we wanted to understand their perceptions of current curricular content and to receive suggestions for improving scientific competency training. Participants were reached via the mailing lists of the German Medical Students’ Association, as well as of local medical student committees, and the German Medical Students’ Associations social media channel on Facebook.
Results: In total, 2380 medical students from across all 37 German medical faculties participated in the survey. The majority of students agreed that the ability to critically evaluate the relevant literature is an important competency for physicians, and that every student should conduct a research project during their medical studies. However, the students evaluated their scientific competencies as unsatisfactory, especially with regard to statistics and scientific writing. They were strongly in favor of receiving extended research training.
Conclusion: Our study provides insight into German medical students’ self-perception in relation to both patient care and biomedical research, and makes recommendations for potential improvements in scientific training. The study demonstrates that scientific competencies are of great importance to medical students in Germany. Students are not lacking motivation for scientific practice and have numerous ideas for enhancing scientific teaching opportunities. Scientific training should follow a holistic approach based on three pillars: (i) a scientific core curriculum, (ii) intracurricular research projects, and (iii) special research programs for students strongly interested in medical research
Wave Function Shredding by Sparse Quantum Barriers
We discuss a model in which a quantum particle passes through
potentials arranged in an increasingly sparse way. For infinitely many barriers
we derive conditions, expressed in terms ergodic properties of wave function
phases, which ensure that the point and absolutely continuous parts are absent
leaving a purely singularly continuous spectrum. For a finite number of
barriers, the transmission coefficient shows extreme sensitivity to the
particle momentum with fluctuation in many different scales. We discuss a
potential application of this behavior for erasing the information carried by
the wave function.Comment: 4 pages ReVTeX with 3 epsf figure
On the equality of Hausdorff and box counting dimensions
By viewing the covers of a fractal as a statistical mechanical system, the
exact capacity of a multifractal is computed. The procedure can be extended to
any multifractal described by a scaling function to show why the capacity and
Hausdorff dimension are expected to be equal.Comment: CYCLER Paper 93mar001 Latex file with 3 PostScript figures (needs
psfig.sty
Negative differential conductivity in an interacting quantum gas
Negative differential conductivity (NDC) is a widely exploited effect in
modern electronic components. Here, a proof-of-principle is given for the
observation of NDC in a quantum transport device for neutral atoms employing a
multi-mode tunneling junction. The transport of the many-body quantum system is
governed by the interplay between the tunnel coupling, the interaction energy
and the thermodynamics of intrinsic collisions, which turn the coherent
coupling into a hopping process. The resulting current voltage characteristics
exhibit NDC, for which we identify a new microscopic physical mechanism. Our
study opens new ways for the future implementation and control of complex
neutral atom quantum circuits
The Lazarus Effect: Healing Compromised Devices in the Internet of Small Things
We live in a time when billions of IoT devices are being deployed and
increasingly relied upon. This makes ensuring their availability and
recoverability in case of a compromise a paramount goal. The large and rapidly
growing number of deployed IoT devices make manual recovery impractical,
especially if the devices are dispersed over a large area. Thus, there is a
need for a reliable and scalable remote recovery mechanism that works even
after attackers have taken full control over devices, possibly misusing them or
trying to render them useless.
To tackle this problem, we present Lazarus, a system that enables the remote
recovery of compromised IoT devices. With Lazarus, an IoT administrator can
remotely control the code running on IoT devices unconditionally and within a
guaranteed time bound. This makes recovery possible even in case of severe
corruption of the devices' software stack. We impose only minimal hardware
requirements, making Lazarus applicable even for low-end constrained
off-the-shelf IoT devices. We isolate Lazarus's minimal recovery trusted
computing base from untrusted software both in time and by using a trusted
execution environment. The temporal isolation prevents secrets from being
leaked through side-channels to untrusted software. Inside the trusted
execution environment, we place minimal functionality that constrains untrusted
software at runtime.
We implement Lazarus on an ARM Cortex-M33-based microcontroller in a full
setup with an IoT hub, device provisioning and secure update functionality. Our
prototype can recover compromised embedded OSs and bare-metal applications and
prevents attackers from bricking devices, for example, through flash wear out.
We show this at the example of FreeRTOS, which requires no modifications but
only a single additional task. Our evaluation shows negligible runtime
performance impact and moderate memory requirements.Comment: In Proceedings of the 15th ACM Asia Conference on Computer and
Communications Security (ASIA CCS 20
Evaluation of Transformer Architectures for Electrical Load Time-Series Forecasting
Accurate forecasts of the electrical load are needed to stabilize the electrical grid and maximize the use of renewable energies. Many good forecasting methods exist, including neural networks, and we compare them to the recently developed Transformers, which are the state-of-the-art machine learning technique for many sequence-related tasks. We apply different types of Transformers, namely the Time-Series Transformer, the Convolutional Self-Attention Transformer and the Informer, to electrical load data from Baden-Württemberg. Our results show that the Transformes give up to 11% better forecasts than multi-layer perceptrons for long prediction horizons. Furthermore, we analyze the Transformers’ attention scores to get insights into the model
The nature of the Galactic Center source IRS 13 revealed by high spatial resolution in the infrared
High spatial resolution observations in the 1 to 3.5 micron region of the
Galactic Center source known historically as IRS 13 are presented. They include
ground-based adaptive optics images in the H, Kp (2.12/0.4 micron) and L bands,
NICMOS data in filters between 1.1 and 2.2 micron, and integral field
spectroscopic data from BEAR, an Imaging FTS, in the HeI 2.06 micron and the
Br line regions. Analysis of all these data provides a completely new
picture of the main component, IRS 13E, which appears as a cluster of seven
individual stars within a projected diameter of ~0.5'' (0.02 pc). The brightest
sources, 13E1, 13E2, 13E3 (a binary), and 13E4, are all massive stars, 13E1 a
blue object, with no detected emission line while 13E2 and 13E4 are high-mass
emission line stars. 13E2 is at the WR stage and 13E4 a massive O-type star.
13E3A and B are extremely red objects, proposed as other examples of dusty WR
stars. All these sources have a common westward proper motion. 13E5, is a red
source similar to 13E3A/B. This concentration of comoving massive hot stars,
IRS 13E, is proposed as the remaining core of a massive star cluster, which
could harbor an intermediate-mass black hole (IMBH) of ~1300 M_sol. This
detection plays in favor of a scenario in which the helium stars and the other
hot stars in the central pc originate from the stripping of a massive cluster
formed several tens of pc from the center. The detection of a discrete X-ray
emission (Baganoff et al. 2003) at the IRS~13 position is examined in this
context.Comment: 14 pages, 6 figures (3 in color), LaTeX2e, accepted in A&
Simultaneous 3D measurement of the translation and rotation of finite size particles and the flow field in a fully developed turbulent water flow
We report a novel experimental technique that measures simultaneously in
three dimensions the trajectories, the translation, and the rotation of finite
size inertial particles together with the turbulent flow. The flow field is
analyzed by tracking the temporal evolution of small fluorescent tracer
particles. The inertial particles consist of a super-absorbent polymer that
renders them index and density matched with water and thus invisible. The
particles are marked by inserting at various locations tracer particles into
the polymer. Translation and rotation, as well as the flow field around the
particle are recovered dynamically from the analysis of the marker and tracer
particle trajectories. We apply this technique to study the dynamics of
inertial particles much larger in size (Rp/{\eta} \approx 100) than the
Kolmogorov length scale {\eta} in a von K\'arm\'an swirling water flow
(R{\lambda} \approx 400). We show, using the mixed (particle/fluid) Eulerian
second order velocity structure function, that the interaction zone between the
particle and the flow develops in a spherical shell of width 2Rp around the
particle of radius Rp. This we interpret as an indication of a wake induced by
the particle. This measurement technique has many additional advantages that
will make it useful to address other problems such as particle collisions,
dynamics of non-spherical solid objects, or even of wet granular matter.Comment: 18 pages, 7 figures, submitted to "Measurement Science and
Technology" special issue on "Advances in 3D velocimetry
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