2,899 research outputs found
On quantum plasma: a plea for a common sense
The quantum plasma theory has flourished in the past few years without much
regard to the physical validity of the formulation or its connection to any
real physical system. It is argued here that there is a very limited physical
ground for the application of such a theory.Comment: EPL, to be published 201
Adaptive Tuning of Feedback Gain in Time-Delayed Feedback Control
We demonstrate that time-delayed feedback control can be improved by
adaptively tuning the feedback gain. This adaptive controller is applied to the
stabilization of an unstable fixed point and an unstable periodic orbit
embedded in a chaotic attractor. The adaptation algorithm is constructed using
the speed-gradient method of control theory. Our computer simulations show that
the adaptation algorithm can find an appropriate value of the feedback gain for
single and multiple delays. Furthermore, we show that our method is robust to
noise and different initial conditions.Comment: 7 pages, 6 figure
Prediction of solar particle events with SRAM-based soft error rate monitor and supervised machine learning
This work introduces an embedded approach for the prediction of Solar Particle Events (SPEs) in space applications by combining the real-time Soft Error Rate (SER) measurement with SRAM-based detector and the offline trained machine learning model. The proposed approach is intended for the self-adaptive fault-tolerant multiprocessing systems employed in space applications. With respect to the state-of-the-art, our solution allows for predicting the SER 1 h in advance and fine-grained hourly tracking of SER variations during SPEs as well as under normal conditions. Therefore, the target system can activate the appropriate mechanisms for radiation hardening before the onset of high radiation levels. Based on the comparison of five different machine learning algorithms trained with the public space flux database, the preliminary results indicate that the best prediction accuracy is achieved with the recurrent neural network (RNN) with long short-term memory (LSTM). © 2020 The Author
Further study of the Over-Barrier Model to compute charge exchange processes
In this paper we study theoretically the process of electron capture between
one-optical-electron atoms (e.g. hydrogenlike or alkali atoms) and ions at
low-to-medium impact velocities () working on a modification
of an already developed classical In this work we present an improvement over
the Over Barrier Model (OBM) described in a recent paper [F. Sattin, Phys. Rev.
A {\bf 62}, 042711 (2000)]. We show that: i) one of the two free parameters
there introduced actually comes out consistently from the starting assumptions
underlying the model; ii) the modified model thus obtained is as much accurate
as the former one. Furthermore, we show that OBMs are able to accurately
predict some recent results of state selective electron capture, at odds with
what previously supposed.Comment: RevTeX, 7 pages, 4 eps figures. To appear in Physical Review A
(2001-september issue
The role of farmed fish in the diets of the resource-poor in Egypt.
The Egyptian aquaculture industry provides more than 100,000 full-time or part-time jobs and produces the country’s least-expensive farmed animal protein. Thus, aquaculture plays an important role in both sustaining livelihoods and improving the diet quality and nutritional health of Egyptians, including a significant proportion of the 25.5% who are resource-poor. Recognizing this dual role, WorldFish has promoted sustainable growth in Egyptian aquaculture for more than 20 years. Through its work, WorldFish has identified a lack of quality data about fish consumption preferences and practices. Eager to fill this knowledge gap, WorldFish partnered with the Environment and Development Group (EDG) to study consumption of fish, red meat and poultry among the resource-poor in Egypt. This study aimed to characterize current consumer preferences for and consumption patterns of animal-source foods, comparing red meat, poultry and fish. The resulting data is meant to contribute to a better understanding of what drives demand for fish among the resource-poor in Egypt, allowing value chain actors to more successfully market their products to this segment of the population
Anti-CTLA-4 therapy for malignant mesothelioma
Immunotherapy is an emerging therapeutic strategy with a promising clinical outcome in some solid tumors, particularly metastatic melanoma. One approach to immunotherapy is immune checkpoint inhibitors, such as blockage of CTLA-4 and PD-1/PD-L1. This special report aims to describe the state of clinical trials of tremelimumab in patients with unresectable malignant mesothelioma (MM) in particular with regard to the clinical efficacy, safety and tolerability. Criticism and perspective of this treatment are also discussed. Biological and clinical considerations rule out the use of tremelimumab as single agent for MM and, more generally, the use of immune checkpoint inhibitors for MM is still largely questionable and not supported by evidences
A classical Over Barrier Model to compute charge exchange between ions and one-optical-electron atoms
In this paper we study theoretically the process of electron capture between
one-optical-electron atoms (e.g. hydrogenlike or alkali atoms) and ions at
low-to-medium impact velocities (v/v_e <= 1) working on a modification of an
already developed classical Over Barrier Model (OBM) [V. Ostrovsky, J. Phys. B:
At. Mol. Opt. Phys. {\bf 28} 3901 (1995)], which allows to give a
semianalytical formula for the cross sections. The model is discussed and then
applied to a number of test cases including experimental data as well as data
coming from other sophisticated numerical simulations. It is found that the
accuracy of the model, with the suggested corrections and applied to quite
different situations, is rather high.Comment: 12 pages REVTEX, 5 EPSF figures, submitted to Phys Rev
Comparative study on the implementation of the ECHR at the national level
A Comparative analysis of the application of the European Convention on Human Rights in the national legal framework of several contracting states to the Conventio
The effect of subchronic supplementation with folic acid on homocysteine induced seizures
Influence of folic acid on the CNS is still unclear. Folate has a neuroprotective effect, while on the other hand excess folate can exacerbate seizures in epileptics. The aim of the present study was to examine the effect of subchronic administration of folic acid on behavioural and electroencephalographic (EEG) characteristics of DL homocysteine thiolactone induced seizures in adult rats. The activity of Na+/K+-ATPase and Mg2+-ATPase in different brain regions was investigated. Adult male Wistar rats were divided into groups: 1. Controls (C, 0.9% NaCl); 2. DL homocysteine-thiolactone 8.0 mmol/kg (H); 3. Subchronic supplementation with folic acid 5 mg/kg for 7 days (F) and 4. Subchronic supplementation with F + single dose of H (FH). Seizure behaviour was assessed by incidence, latency, number and intensity of seizure episodes. Seizure severity was described by a descriptive scale with grades 0–4. For EEG recordings, three gold-plated recording electrodes were implanted into the skull. Subchronic supplementation with folic acid did not affect seizure incidence, median number of seizure episodes and severity in FH, comparison with H (p > 0.05). The majority of seizure episodes in all groups were of grade 2. There were no significant differences in lethal outcomes at 24 h upon H injection in the FH vs. H group. The activity of Na+/K+-ATPase and Mg2+-ATPase was significantly increased in almost all examined structures in the FH vs. H group. Subchronic folic acid administration did not exacerbate H induced seizures and completely recovered the activity of ATPases
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