Hausdorff clustering of financial time series

A clustering procedure, based on the Hausdorff distance, is introduced and tested on the financial time series of the Dow Jones Industrial Average (DJIA) index.Comment: 9 pages, 3 figure

Positive and Negative Regulation of Cellular Immune Responses in Physiologic Conditions and Diseases

The immune system has evolved to allow robust responses against pathogens while avoiding autoimmunity. This is notably enabled by stimulatory and inhibitory signals which contribute to the regulation of immune responses. In the presence of a pathogen, a specific and effective immune response must be induced and this leads to antigen-specific T-cell proliferation, cytokines production, and induction of T-cell differentiation toward an effector phenotype. After clearance or control of the pathogen, the effector immune response must be terminated in order to avoid tissue damage and chronic inflammation and this process involves coinhibitory molecules. When the immune system fails to eliminate or control the pathogen, continuous stimulation of T cells prevents the full contraction and leads to the functional exhaustion of effector T cells. Several evidences both in vitro and in vivo suggest that this anergic state can be reverted by blocking the interactions between coinhibitory molecules and their ligands. The potential to revert exhausted or inactivated T-cell responses following selective blocking of their function made these markers interesting targets for therapeutic interventions in patients with persistent viral infections or cancer

Magnetic Monopoles in Ferromagnetic Spin-Triplet Superconductors

Using the $\phi$-mapping method, we argue that ferromagnetic spin-triplet superconductors allow formation of unstable magnetic monopoles. In particular, we show that the limit points and the bifurcation points of the $\phi$-mapping will serve as the interaction points of these magnetic monopoles.Comment: 4 pages, no figure

Hybrid solar-biomass combined Brayton/organic Rankine-cycle plants integrated with thermal storage: Techno-economic feasibility in select Mediterranean areas

This paper presents a thermodynamic analysis and techno-economic assessment of a novel hybrid solar-biomass power-generation system configuration composed of an externally fired gas-turbine (EFGT) fuelled by biomass (wood chips) and a bottoming organic Rankine cycle (ORC) plant. The main novelty is related to the heat recovery from the exhaust gases of the EFGT via thermal energy storage (TES), and integration of heat from a parabolic-trough collectors (PTCs) field with molten salts as a heat-transfer fluid (HTF). The presence of a TES between the topping and bottoming cycles facilitates the flexible operation of the system, allows the system to compensate for solar energy input fluctuations, and increases capacity factor and dispatchability. A TES with two molten salt tanks (one cold at 200 °C and one hot at 370 °C) is chosen. The selected bottoming ORC is a superheated recuperative cycle suitable for heat conversion in the operating temperature range of the TES. The whole system is modelled by means of a Python-based software code, and three locations in the Mediterranean area are assumed in order to perform energy-yield analyses: Marseille in France, Priolo Gargallo in Italy and Rabat in Morocco. In each case, the thermal storage that minimizes the levelized cost of energy (LCE) is selected on the basis of the estimated solar radiation and CSP size. The results of the thermodynamic simulations, capital and operational costs assessments and subsidies (feed-in tariffs for biomass and solar electricity available in the Italian framework), allow estimating the global energy conversion efficiency and the investment profitability in the three locations. Sensitivity analyses of the biomass costs, size of PTCs, feed-in tariff and share of cogenerated heat delivered to the load are also performed. The results show that the high investment costs of the CSP section in the proposed size range and hybridization configuration allow investment profitability only in the presence of a dedicated subsidy framework such as the one available in the Italian energy market. In particular, the LCE of the proposed system is around 140 Eur/MWh (with the option to discharge the cogenerated heat) and the IRR is around 15%, based on the Italian electricity subsidy tariffs. The recovery of otherwise discharged heat to match thermal energy demand can significantly increase the investment profitability and compensate the high investment costs of the proposed technology

Proposal to Increase the LEP Energy with Horizontal Orbit Correctors

In an e+ e- collider the beam energy depends only on the bending field integral "Bds while the synchrotron radiation power scales with "B2ds and is sensitive to the details of the field distribution. With fixed RF acceleration voltage it is thus possible to attain higher energies by increasing the effective bending magnet length. We propose to use the horizontal orbit correctors to exploit this effect. To control the orbit perturbations, 79 unused correctors in the regular arcs and 14 unused correctors in the dispersion suppressors will have to be powered. An energy increase of approximatively 0.18 GeV per beam might be obtained

Multi-time-scale features for accurate respiratory sound classification

The COVID-19 pandemic has amplified the urgency of the developments in computer-assisted medicine and, in particular, the need for automated tools supporting the clinical diagnosis and assessment of respiratory symptoms. This need was already clear to the scientific community, which launched an international challenge in 2017 at the International Conference on Biomedical Health Informatics (ICBHI) for the implementation of accurate algorithms for the classification of respiratory sound. In this work, we present a framework for respiratory sound classification based on two different kinds of features: (i) short-term features which summarize sound properties on a time scale of tenths of a second and (ii) long-term features which assess sounds properties on a time scale of seconds. Using the publicly available dataset provided by ICBHI, we cross-validated the classification performance of a neural network model over 6895 respiratory cycles and 126 subjects. The proposed model reached an accuracy of 85% ± 3% and an precision of 80% ± 8%, which compare well with the body of literature. The robustness of the predictions was assessed by comparison with state-of-the-art machine learning tools, such as the support vector machine, Random Forest and deep neural networks. The model presented here is therefore suitable for large-scale applications and for adoption in clinical practice. Finally, an interesting observation is that both short-term and long-term features are necessary for accurate classification, which could be the subject of future studies related to its clinical interpretation

Hausdorff clustering

A clustering algorithm based on the Hausdorff distance is introduced and compared to the single and complete linkage. The three clustering procedures are applied to a toy example and to the time series of financial data. The dendrograms are scrutinized and their features confronted. The Hausdorff linkage relies of firm mathematical grounds and turns out to be very effective when one has to discriminate among complex structures.Comment: 12 pages, 13 figure

Inhibition of an erythrocyte tyrosine kinase with imatinib prevents <i>Plasmodium falciparum</i> egress and terminates parasitemia

With half of the world’s population at risk for malaria infection and with drug resistance on the rise, the search for mutation-resistant therapies has intensified. We report here a therapy for Plasmodium falciparum malaria that acts by inhibiting the phosphorylation of erythrocyte membrane band 3 by an erythrocyte tyrosine kinase. Because tyrosine phosphorylation of band 3 causes a destabilization of the erythrocyte membrane required for parasite egress, inhibition of the erythrocyte tyrosine kinase leads to parasite entrapment and termination of the infection. Moreover, because one of the kinase inhibitors to demonstrate antimalarial activity is imatinib, i.e. an FDA-approved drug authorized for use in children, translation of the therapy into the clinic will be facilitated. At a time when drug resistant strains of P. falciparum are emerging, a strategy that targets a host enzyme that cannot be mutated by the parasite should constitute a therapeutic mechanism that will retard evolution of resistance

Inhibition of an erythrocyte tyrosine kinase with imatinib prevents Plasmodium falciparum egress and terminates parasitemia

With half of the world's population at risk for malaria infection and with drug resistance on the rise, the search for mutation-resistant therapies has intensified. We report here a therapy for Plasmodium falciparum malaria that acts by inhibiting the phosphorylation of erythrocyte membrane band 3 by an erythrocyte tyrosine kinase. Because tyrosine phosphorylation of band 3 causes a destabilization of the erythrocyte membrane required for parasite egress, inhibition of the erythrocyte tyrosine kinase leads to parasite entrapment and termination of the infection. Moreover, because one of the kinase inhibitors to demonstrate antimalarial activity is imatinib, i.e. an FDA-approved drug authorized for use in children, translation of the therapy into the clinic will be facilitated. At a time when drug resistant strains of P. falciparum are emerging, a strategy that targets a host enzyme that cannot be mutated by the parasite should constitute a therapeutic mechanism that will retard evolution of resistance

Association of plasma zinc levels with anti-SARS-CoV-2 IgG and IgA seropositivity in the general population: A case-control study.

Some micronutrients have key roles in immune defence, including mucosal defence mechanisms and immunoglobulin production. Altered micronutrient status has been linked with COVID-19 infection and disease severity. We assessed the associations of selected circulating micronutrients with anti-SARS-CoV-2 IgG and IgA seropositivity in the Swiss community using early pandemic data. Case-control study comparing the first PCR-confirmed COVID-19 symptomatic cases in the Vaud Canton (May to June 2020, n = 199) and controls (random population sample, n = 447), seronegative for IgG and IgA. The replication analysis included seropositive (n = 134) and seronegative (n = 152) close contacts from confirmed COVID-19 cases. Anti-SARS-CoV-2 IgG and IgA levels against the native trimeric spike protein were measured using the Luminex immunoassay. We measured plasma Zn, Se and Cu concentrations by ICP-MS, and 25-hydroxy-vitamin D &lt;sub&gt;3&lt;/sub&gt; (25(OH)D &lt;sub&gt;3&lt;/sub&gt; ) with LC-MS/MS and explored associations using multiple logistic regression. The 932 participants (54.1% women) were aged 48.6 ± 20.2 years (±SD), BMI 25.0 ± 4.7 kg/m &lt;sup&gt;2&lt;/sup&gt; with median C-Reactive Protein 1 mg/l. In logistic regressions, log &lt;sub&gt;2&lt;/sub&gt; (Zn) plasma levels were negatively associated with IgG seropositivity (OR [95% CI]: 0.196 [0.0831; 0.465], P &lt; 0.001; replication analyses: 0.294 [0.0893; 0.968], P &lt; 0.05). Results were similar for IgA. We found no association of Cu, Se, and 25(OH)D &lt;sub&gt;3&lt;/sub&gt; with anti-SARS-CoV-2 IgG or IgA seropositivity. Low plasma Zn levels were associated with higher anti-SARS-CoV-2 IgG and IgA seropositivity in a Swiss population when the initial viral variant was circulating, and no vaccination available. These results suggest that adequate Zn status may play an important role in protecting the general population against SARS-CoV-2 infection. CORONA IMMUNITAS:: ISRCTN18181860