COMET: A Recipe for Learning and Using Large Ensembles on Massive Data

COMET is a single-pass MapReduce algorithm for learning on large-scale data. It builds multiple random forest ensembles on distributed blocks of data and merges them into a mega-ensemble. This approach is appropriate when learning from massive-scale data that is too large to fit on a single machine. To get the best accuracy, IVoting should be used instead of bagging to generate the training subset for each decision tree in the random forest. Experiments with two large datasets (5GB and 50GB compressed) show that COMET compares favorably (in both accuracy and training time) to learning on a subsample of data using a serial algorithm. Finally, we propose a new Gaussian approach for lazy ensemble evaluation which dynamically decides how many ensemble members to evaluate per data point; this can reduce evaluation cost by 100X or more

Nitrogen removal in fixed-bed submerged biofilters without backwashing

The paper reports the findings of four years of pilot-scale research on nitrogen removal in fixed-bed biofilters fed on real raw municipal wastewater. The plant was made of two fixed-bed biofilm reactors in series with an intermediate settling tank from which excess biomass from the first stage was discharged. The first filter was used for carbon removal either with oxygen or nitrates. The second filter was used for nitrification. The average nitrification rate at 20°C was 0.84 gNH 4 + -N m −2 d −1 with 5 mg l −1 dissolved oxygen in the bulk liquid. Temperature dependence was calculated (r n = r n,20° 1,05 T-20 ). The influent organic load strongly affected ammonia oxidation. If the organic loading exceeded 2.5 gCOD m −2 d −1 nitrification rate was reduced by 50%. Denitrification was performed by recycling nitrates back from the second filter and by using sewage itself as carbon source. Denitrification rate showed to be strongly dependent on temperature (r d = r d,20° 1.11 T-20 ) and on the recycle rate. Hydrolysis of the colloidal COD fraction showed a similar dependence on both temperature and recycle rate. Therefore, it has been concluded that the hydrolysis of finely dispersed COD particles can be the limiting step of denitrification in the biofilter when real sewage is used as carbon source

Oxidative inactivation of SARS-CoV-2 on photoactive AgNPs@Tio2 ceramic tiles

The current SARS-CoV-2 pandemic causes serious public health, social, and economic issues all over the globe. Surface transmission has been claimed as a possible SARS-CoV-2 infection route, especially in heavy contaminated environmental surfaces, including hospitals and crowded public places. Herein, we studied the deactivation of SARS-CoV-2 on photoactive AgNPs@TiO2 coated on industrial ceramic tiles under dark, UVA, and LED light irradiations. SARS-CoV-2 inactivation is effective under any light/dark conditions. The presence of AgNPs has an important key to limit the survival of SARS-CoV-2 in the dark; moreover, there is a synergistic action when TiO2 is decorated with Ag to enhance the virus photocatalytic inactivation even under LED. The radical oxidation was confirmed as the the central mechanism behind SARS-CoV-2 damage/inactivation by ESR analysis under LED light. Therefore, photoactive AgNPs@TiO2 ceramic tiles could be exploited to fight surface infections, especially during viral severe pandemics

Facile Preparation of N-Glycosylated 10-Piperazinyl Artemisinin Derivatives and Evaluation of Their Antimalarial and Cytotoxic Activities

According to the precepts that C-10 amino-artemisinins display optimum biological activities for the artemisinin drug class, and that attachment of a sugar enhances specificity of drug delivery, polarity and solubility so as to attenuate toxicity, we assessed the effects of attaching sugars to N-4 of the dihydroartemisinin (DHA)-piperazine derivative prepared in one step from DHA and piperazine. N-Glycosylated DHA-piperazine derivatives were obtained according to the Kotchetkov reaction by heating the DHA-piperazine with the sugar in a polar solvent. Structure of the D-glucose derivative is secured by X-ray crystallography. The D-galactose, L-rhamnose and D-xylose derivatives displayed IC50 values of 0.58\u20130.87 nM against different strains of Plasmodium falciparum (Pf ) and selectivity indices (SI) >195, on average, with respect to the mouse fibroblast WEHI-164 cell line. These activities are higher than those of the amino-artemisinin, artemisone (IC50 0.9\u20131.1 nM). Notably, the D-glucose, D-maltose and D-ribose derivatives were the most active against the myelogenous leukemia K562 cell line with IC50 values of 0.78\u20130.87 M and SI > 380 with respect to the human dermal fibroblasts (HDF). In comparison, artemisone has an IC50 of 0.26 M, and a SI of 88 with the same cell lines. Overall, the N-glycosylated DHA-piperazine derivatives display antimalarial activities that are greatly superior to O-glycosides previously obtained from DHA

Heart rate variability and early recurrence of atrial fibrillation after electrical cardioversion

The study evaluated the role of the autonomic nervous system in atrial fibrillation (AF) recurrence

Digitalized Cognitive Assessment mediated by a Virtual Caregiver

The ageing of the population deeply impacts on the social costs relative to health care. The use of modern technologies is one of the most promising approaches, under current study, to reduce such impact. In this demonstration, we propose a framework that can be employed for at-home assessment of Mild Cognitive Impairment (MCI). It is composed by a set of digitalized cognitive tests, developed from their paper-and-pencil counterparts, and by a Virtual Caregiver, which oversees the test execution and provides instructions.</jats:p

Salinomycin and Other Ionophores as a New Class of Antimalarial Drugs with Transmission-Blocking Activity

The drug target profile proposed by the Medicines for Malaria Venture for a malaria elimination/eradication policy focuses on molecules active on both asexual and sexual stages of Plasmodium, thus with both curative and transmission-blocking activities. The aim of the present work was to investigate whether the class of monovalent ionophores, which includes drugs used in veterinary medicine and that were recently proposed as human anticancer agents, meets these requirements. The activity of salinomycin, monensin, and nigericin on Plasmodium falciparum asexual and sexual erythrocytic stages and on the development of the Plasmodium berghei and P. falciparum mosquito stages is reported here. Gametocytogenesis of the P. falciparum strain 3D7 was induced in vitro, and gametocytes at stage II and III or stage IV and V of development were treated for different lengths of time with the ionophores and their viability measured with the parasite lactate dehydrogenase (pLDH) assay. The monovalent ionophores efficiently killed both asexual parasites and gametocytes with a nanomolar 50% inhibitory concentration (IC50). Salinomycin showed a fast speed of kill compared to that of standard drugs, and the potency was higher on stage IV and V than on stage II and III gametocytes. The ionophores inhibited ookinete development and subsequent oocyst formation in the mosquito midgut, confirming their transmission-blocking activity. Potential toxicity due to hemolysis was excluded, since only infected and not normal erythrocytes were damaged by ionophores. Our data strongly support the downstream exploration of monovalent ionophores for repositioning as new antimalarial and transmission-blocking leads

Evaluating the Acceptability of Assistive Robots for Early Detection of Mild Cognitive Impairment

The employment of Social Assistive Robots (SARs) for monitoring elderly users represents a valuable gateway for at-home assistance. Their deployment in the house of the users can provide effective opportunities for early detection of Mild Cognitive Impairment (MCI), a condition of increasing impact in our aging society, by means of digitalized cognitive tests. In this work, we present a system where a specific set of cognitive tests is selected, digitalized, and integrated with a robotic assistant, whose task is the guidance and supervision of the users during the completion of such tests. The system is then evaluated by means of an experimental study involving potential future users, in order to assess its acceptability and identify key directions for technical improvements