8 research outputs found
EDEN: A high-performance, general-purpose, NeuroML-based neural simulator
Modern neuroscience employs in silico experimentation on ever-increasing and
more detailed neural networks. The high modelling detail goes hand in hand with
the need for high model reproducibility, reusability and transparency. Besides,
the size of the models and the long timescales under study mandate the use of a
simulation system with high computational performance, so as to provide an
acceptable time to result. In this work, we present EDEN (Extensible Dynamics
Engine for Networks), a new general-purpose, NeuroML-based neural simulator
that achieves both high model flexibility and high computational performance,
through an innovative model-analysis and code-generation technique. The
simulator runs NeuroML v2 models directly, eliminating the need for users to
learn yet another simulator-specific, model-specification language. EDEN's
functional correctness and computational performance were assessed through
NeuroML models available on the NeuroML-DB and Open Source Brain model
repositories. In qualitative experiments, the results produced by EDEN were
verified against the established NEURON simulator, for a wide range of models.
At the same time, computational-performance benchmarks reveal that EDEN runs up
to 2 orders-of-magnitude faster than NEURON on a typical desktop computer, and
does so without additional effort from the user. Finally, and without added
user effort, EDEN has been built from scratch to scale seamlessly over multiple
CPUs and across computer clusters, when available.Comment: 29 pages, 9 figure
Mediastinal debulking for a T-cell leukaemia/lymphoma presenting with cardiac tamponade
Anterior mediastinal masses are relatively uncommon and include a wide variety of lesions. Lymphomas account for 25% of anterior mediastinal masses. Lymphomas and other haematological malignancies are associated with pericardial effusion. There are also cases where a cardiac tamponade occurred. The aim of the case reported herein is to discuss the surgical approach and particularly the mediastinal debulking as an adjunct to systematic treatment for haematological diseases presenting as an anterior mediastinal mass responsible for a cardiac tamponade
A novel simulator for extended Hodgkin-Huxley neural networks
Computational neuroscience aims to investigate and explain the behaviour and functions of neural structures, through mathematical models. Due to the models' complexity, they can only be explored through computer simulation. Modern research in this field is increasingly adopting large networks of neurons, and diverse, physiologically-detailed neuron models, based on the extended Hodgkin-Huxley (eHH) formalism. However, existing eHH simulators either support highly specific neuron models, or they provide low computational performance, making model exploration costly in time and effort. This work introduces a simulator for extended Hodgkin-Huxley neural networks, on multiprocessing platforms. This simulator supports a broad range of neuron models, while still providing high performance. Simulator performance is evaluated against varying neuron complexity parameters, network size and density, and thread-level parallelism. Results indicate performance is within existing literature for single-model eHH codes, and scales well for large CPU core counts. Ultimately, this application combines model flexibility with high performance, and can serve as a new tool in computational neuroscience.</p
Dual Emission in the Near-Infrared and Visible Regions from a Mixed Cyanido-Bridged Eu<sup>III</sup>/Nd<sup>III</sup>(4-OHpy)-Co<sup>III</sup> Layered Material
Coordination polymers (CPs) with a dual emission spanning
from
the visible (vis) to near-infrared (NIR) regions of the electromagnetic
spectrum are used for optical sensors, medical diagnostics, and telecommunication
technologies. We herein report the synthesis, structural characterization,
and optical response of heterometallic cyanido-bridged layered {[EuxNdy(4-OHpy)2(H2O)3][Co(CN)6]} CPs, where
4-OHpy = 4-hydroxypyridine, with a multicolor emission profile across
the vis and NIR regions. The crystals show an efficient energy transfer
(ET) from the 4-OHpy ligand and the [Co(CN)6] ions to the
Eu3+ and Nd3+ ions, resulting in an enhanced
photoluminescence (PL) efficiency. We study the ET with steady-state
and time-resolved PL, reporting an ET between the Ln3+ centers.
The excitation-dependent emission of the mixed Ln3+ CPs
and the control over the PL lifetime yield new insights into the optoelectronic
properties of these materials
Red Blood Cell Abnormalities as the Mirror of SARS-CoV-2 Disease Severity: A Pilot Study
PurposeUnraveling the pathophysiology of COVID-19 disease is of crucial
importance for designing treatment. The purpose of this study is to
investigate the effects of the disease on erythrocytes (RBCs) and to
correlate the findings with disease severity. Materials and
MethodsHospitalized patients (n = 36) with COVID-19 and control group of
healthy volunteers (n = 18) were included in the study. Demographic
data, clinical, laboratory and chest Computed Tomography (CT) findings
at time of admission were recorded. Laboratory measurements included:
Hemoglobin (H b), indirect billirubin, LDH, D-Dimers, and plasma free
hemoglobin (plasma free-Hb). On RBCs were performed: osmotic fragility
(MCF), Free-Hb after mechanical stress (Free-Hb-MECH), intracellular RBC
concentration of calcium ions (iCa(2+)), intracellular ROS (iROS), G6PD,
intracellular active caspase-3 (RBC-caspase-3), IgG immunoglobulins
(RBC-IgGs), which are bound on RBCs’ senescent neo-antigen proteins and
RBC surface phosphatidylserine (RBC-PS). ResultsThe percentage of males
was 50 and 66% and the mean age was 65.16 +/- 14.24 and 66.33 +/- 13.48
years among patients and controls respectively (mean +/- SD, p = 0.78).
Upon admission patients’ PO2/FiO(2) ratio was 305.92 +/- 76.75 and
distribution of infiltration extend on chest CT was: 0-25% (N = 19),
25-50%: (N = 7), and 50-75% (N = 9). Elevated hemolysis markers (LDH
and plasma free-Hb) were observed in patients compared to the control
group. Patients’ RBCs were more sensitive to mechanical stress, and
exhibited significantly elevated apoptotic markers (iCa(2+), RBC-PS).
Plasma free Hb levels correlated with the extend of pulmonary
infiltrates on chest CT in COVID-19 patients. Surprisingly, patients’
RBC-iROS were decreased, a finding possibly related with the increased
G6PDH levels in this group, suggesting a possible compensatory mechanism
against the virus. This compensatory mechanism seemed to be attenuated
as pulmonary infiltrates on chest CT deteriorated. Furthermore, RBC-IgGs
correlated with the severity of pulmonary CT imaging features as well as
the abnormality of lung function, which are both associated with
increased disease severity. Lastly, patients’ D-Dimers correlated with
RBC surface phosphatidylserine, implying a possible contribution of the
red blood cells in the thrombotic diathesis associated with the
SARS-CoV-2 disease. ConclusionThis pilot study suggests that SARS-CoV-2
infection has an effect on red blood cells and there seems to be an
association between RBC markers and disease severity in these patients