3,238 research outputs found
Quiet Sun magnetic fields observed by Hinode: Support for a local dynamo
The Hinode mission has revealed copious amounts of horizontal flux covering
the quiet Sun. Local dynamo action has been proposed to explain the presence of
this flux. We sought to test whether the quiet Sun flux detected by Hinode is
due to a local or the global dynamo by studying long-term variations in the
polarisation signals detectable at the disc centre of the quiet Sun between
November 2006 and May 2012, with particular emphasis on weak signals in the
internetwork. The investigation focusses on line-integrated circular
polarisation V_tot and linear polarisation LP_tot profiles obtained from the Fe
I 6302.5 \AA absorption line in Hinode SOT/SP. Both circular and linear
polarisation signals show no overall variation in the fraction of selected
pixels from 2006 until 2012. There is also no variation in the magnetic flux in
this interval of time. The probability density functions (PDF) of the
line-of-sight magnetic flux can be fitted with a power law from 1.17 x 10^17 Mx
to 8.53 x 10^18 Mx with index \alpha=-1.82 \pm 0.02 in 2007. The variation of
\alpha 's across all years does not exceed a significance of 1\sigma. Linearly
polarised features are also fitted with a power law, with index \alpha=-2.60
\pm 0.06 in 2007. Indices derived from linear polarisation PDFs of other years
also show no significant variation. Our results show that the ubiquitous
horizontal polarisation on the edges of bright granules seen by Hinode are
invariant during the minimum of cycle 23. This supports the notion that the
weak circular and linear polarisation is primarily caused by an independent
local dynamo
BioinspiredLLM: Conversational Large Language Model for the Mechanics of Biological and Bio-inspired Materials
The study of biological materials and bio-inspired materials science is well
established; however, surprisingly little knowledge has been systematically
translated to engineering solutions. To accelerate discovery and guide
insights, an open-source autoregressive transformer large language model,
BioinspiredLLM, is reported. The model was finetuned with a corpus of over a
thousand peer-reviewed articles in the field of structural biological and
bio-inspired materials and can be prompted to actively and interactively recall
information, assist with research tasks, and function as an engine for
creativity. The model has proven by example that it is not only able to
accurately recall information about biological materials when queried but also
formulate biomaterials questions and answers that can evaluate its own
performance. BioinspiredLLM also has been shown to develop sound hypotheses
regarding biological materials design and remarkably so for materials that have
never been explicitly studied before. Lastly, the model showed impressive
promise in collaborating with other generative artificial intelligence models
in a workflow that can reshape the traditional materials design process. This
collaborative generative artificial intelligence method can stimulate and
enhance bio-inspired materials design workflows. Biological materials is at a
critical intersection of multiple scientific fields and models like
BioinspiredLLM help to connect knowledge domains
Radio-frequency operation of a double-island single-electron transistor
We present results on a double-island single-electron transistor (DISET)
operated at radio-frequency (rf) for fast and highly sensitive detection of
charge motion in the solid state. Using an intuitive definition for the charge
sensitivity, we compare a DISET to a conventional single-electron transistor
(SET). We find that a DISET can be more sensitive than a SET for identical,
minimum device resistances in the Coulomb blockade regime. This is of
particular importance for rf operation where ideal impedance matching to 50 Ohm
transmission lines is only possible for a limited range of device resistances.
We report a charge sensitivity of 5.6E-6 e/sqrt(Hz) for a rf-DISET, together
with a demonstration of single-shot detection of small (<=0.1e) charge signals
on microsecond timescales.Comment: 6 pages, 6 figure
Early childhood education: Factors that determine the parental selection of a preschool program
Throughout the ages of mankind, parents have been motivated to provide the best for their children. It has been demonstrated by recent research that parents do have a critical influence on their children\u27s education and development (Grotberg, 1979)
High Positive End-Expiratory Pressure and Lung Recruitment in Moderate to Severe Acute Respiratory Distress Syndrome: Does One Size Really Fit All?
Density dependent spin polarisation in ultra low-disorder quantum wires
There is controversy as to whether a one-dimensional (1D) electron gas can
spin polarise in the absence of a magnetic field. Together with a simple model,
we present conductance measurements on ultra low-disorder quantum wires
supportive of a spin polarisation at B=0. A spin energy gap is indicated by the
presence of a feature in the range 0.5 - 0.7 X 2e^2/h in conductance data.
Importantly, it appears that the spin gap is not static but a function of the
electron density. Data obtained using a bias spectroscopy technique are
consistent with the spin gap widening further as the Fermi-level is increased.Comment: 5 Pages 4 Figures email:[email protected]
Severe Toxic Epidermal Necrolysis and Drug Reaction with Eosinophilia and Systemic Symptoms Overlap Syndrome Treated with Benralizumab: A Case Report
TEN/DRESS overlap syndrome can be difficult to diagnose, especially if it is masked by comorbidities in critically ill patients in intensive care units. The existing therapy for the two conditions is also a major challenge for the treating team. A possible alternative, especially for refractory cases, is benralizumab as an IL-5-receptor alpha-chain-specific humanized monoclonal antibody (IgG1k). We are able to show a successful treatment in this case report
Modeling Single Electron Transfer in Si:P Double Quantum Dots
Solid-state systems such as P donors in Si have considerable potential for
realization of scalable quantum computation. Recent experimental work in this
area has focused on implanted Si:P double quantum dots (DQDs) that represent a
preliminary step towards the realization of single donor charge-based qubits.
This paper focuses on the techniques involved in analyzing the charge transfer
within such DQD devices and understanding the impact of fabrication parameters
on this process. We show that misalignment between the buried dots and surface
gates affects the charge transfer behavior and identify some of the challenges
posed by reducing the size of the metallic dot to the few donor regime.Comment: 11 pages, 7 figures, submitted to Nanotechnolog
Product assurance technology for procuring reliable, radiation-hard, custom LSI/VLSI electronics
Advanced measurement methods using microelectronic test chips are described. These chips are intended to be used in acquiring the data needed to qualify Application Specific Integrated Circuits (ASIC's) for space use. Efforts were focused on developing the technology for obtaining custom IC's from CMOS/bulk silicon foundries. A series of test chips were developed: a parametric test strip, a fault chip, a set of reliability chips, and the CRRES (Combined Release and Radiation Effects Satellite) chip, a test circuit for monitoring space radiation effects. The technical accomplishments of the effort include: (1) development of a fault chip that contains a set of test structures used to evaluate the density of various process-induced defects; (2) development of new test structures and testing techniques for measuring gate-oxide capacitance, gate-overlap capacitance, and propagation delay; (3) development of a set of reliability chips that are used to evaluate failure mechanisms in CMOS/bulk: interconnect and contact electromigration and time-dependent dielectric breakdown; (4) development of MOSFET parameter extraction procedures for evaluating subthreshold characteristics; (5) evaluation of test chips and test strips on the second CRRES wafer run; (6) two dedicated fabrication runs for the CRRES chip flight parts; and (7) publication of two papers: one on the split-cross bridge resistor and another on asymmetrical SRAM (static random access memory) cells for single-event upset analysis
- …