Credit risk prediction in an imbalanced social lending environment

© 2018, the Authors. Credit risk prediction is an effective way of evaluating whether a potential borrower will repay a loan, particularly in peer-to-peer lending where class imbalance problems are prevalent. However, few credit risk prediction models for social lending consider imbalanced data and, further, the best resampling technique to use with imbalanced data is still controversial. In an attempt to address these problems, this paper presents an empirical comparison of various combinations of classifiers and resampling techniques within a novel risk assessment methodology that incorporates imbalanced data. The credit predictions from each combination are evaluated with a G-mean measure to avoid bias towards the majority class, which has not been considered in similar studies. The results reveal that combining random forest and random under-sampling may be an effective strategy for calculating the credit risk associated with loan applicants in social lending markets

Nitrogen Source Differently Regulates Barley (Hordeum vulgare) Response to NaCl Stress At Seed Germination and Early Seedling Development Stages

Nitrogen (N) acts as nutrient and signaling molecule in plants all over their development stages. The involvement of various N forms in the regulation of seed germination response to salt stress was assessed in the present work. Nitrogen sources (NO, NO2−, NO3−, NH4+, glutamine and glutamate) were added at 1mMto the germination medium of barley (Hordeum vulgare, cv Ardhaoui) in combination or not with NaCl stress (14 g.L−1). The application of nitrogen monoxide (NO) alleviated by about 20% the NaCl-induced germination capacity decrease. However, the addition of ammonium ions (NH4+) and glutamic acid (Glu) accentuated the inhibitory effects of NaCl, decreasing germination capacity by about 50% compared to the control. The levels of malondialdehyde (MDA), which is an indicator of membrane lipid peroxidation by stresses, were increased by salinity in seeds treated with nitrite (NO2−), NO3−, Glu and Gln. In N-free medium, NaCl stress induced a severe nitrate reductase activity (NR, EC 1.6.1.6) inhibition. Such an effect was alleviated by the application of N treatments. Glutamate dehydrogenase (GDH, EC 1.4.1.2) aminating activity (NADH-GDH) of seedlings was inhibited by NaCl stress in the presence of NO, Glu and Gln. Conversely, there was stimulation by salt stress of NADH-GDH activity in seedlings treated with NaCl and NH4+. Deaminating GDH activity (NAD-GDH) was found to be enhanced by salt stress in NO2− and NO3− treatments. The differential effects of applied N forms on germination and early seedling development processes in this grass probably underlines different regulatory actions within N mobilization and assimilation

Doctoral symposium: Visualising complex event hierarchies using relevant domain ontologies

© 2017 Copyright held by the owner/author(s). With the growth of data available for analysis, people in many sectors are looking for tools to assist them in collating and visualising patterns in that data. We have developed an event based visualisation system which provides an interactive interface for experts to filter and analyse data. We show that by thinking in terms of events, event hierarchies, and domain ontologies, that we can provide unique results that display patterns within the data being investigated. The proposed system uses a combination of Complex Event Processing (CEP) concepts and domain knowledge via RDF based ontologies. In this case we combine an event model and domain model based on the Financial Industry Business Ontology (FIBO) and conduct experiments on financial data. Our experiments show that, by thinking in terms of event hierarchies, and pre-existing domain ontologies, that certain new relationships between events are more easily discovered

Neuro-Fuzzy fault detection method for photovoltaic systems

Abstract In this work we present a faults detection method for photovoltaic systems (PVS). This method is based on the calculation of sets of parameters of a PV module in different operating conditions, by means of a Neuro-Fuzzy approach. The PV system status is determined by evaluation and comparison of norms based on the aforementioned parameters, with threshold values. This intelligent system developed in Matlab&Simulink environment, consists on the study of the crucial information that the six parameters in normal and faulty condition contain. They are calculated using the I-V curves and synthesized by "hybrid" models. Results show that the diagnosis system is able to discern between normal and faulty operation conditions and with the same defective existence of noise and disturbances

Quark-hadron phase transition in a neutron star under strong magnetic fields

We study the effect of a strong magnetic field on the properties of neutron stars with a quark-hadron phase transition. It is shown that the magnetic field prevents the appearance of a quark phase, enhances the leptonic fraction, decreases the baryonic density extension of the mixed phase and stiffens the total equation of state, including both the stellar matter and the magnetic field contributions. Two parametrisations of a density dependent static magnetic field, increasing, respectively, fast and slowly with the density and reaching $2-4\times 10^{18}$G in the center of the star, are considered. The compact stars with strong magnetic fields have maximum mass configurations with larger masses and radius and smaller quark fractions. The parametrisation of the magnetic field with density has a strong influence on the star properties.Comment: 15 pages, 6 figures, 8 tables, accepted for publication in J. Phys.

Transcriptomic Signature of Leishmania Infected Mice Macrophages: A Metabolic Point of View

We analyzed the transcriptional signatures of mouse bone marrow-derived macrophages at different times after infection with promastigotes of the protozoan parasite Leishmania major. Ingenuity Pathway Analysis revealed that the macrophage metabolic pathways including carbohydrate and lipid metabolisms were among the most altered pathways at later time points of infection. Indeed, L. major promastiogtes induced increased mRNA levels of the glucose transporter and almost all of the genes associated with glycolysis and lactate dehydrogenase, suggesting a shift to anaerobic glycolysis. On the other hand, L. major promastigotes enhanced the expression of scavenger receptors involved in the uptake of Low-Density Lipoprotein (LDL), inhibited the expression of genes coding for proteins regulating cholesterol efflux, and induced the synthesis of triacylglycerides. These data suggested that Leishmania infection disturbs cholesterol and triglycerides homeostasis and may lead to cholesterol accumulation and foam cell formation. Using Filipin and Bodipy staining, we showed cholesterol and triglycerides accumulation in infected macrophages. Moreover, Bodipy-positive lipid droplets accumulated in close proximity to parasitophorous vacuoles, suggesting that intracellular L. major may take advantage of these organelles as high-energy substrate sources. While the effect of infection on cholesterol accumulation and lipid droplet formation was independent on parasite development, our data indicate that anaerobic glycolysis is actively induced by L. major during the establishment of infection

Photosynthetic responses to salinity in two obligate halophytes: Sesuvium portulacastrum and Tecticornia indica

Abstract Seedlings of the obligate halophytes Sesuvium portulacastrum L. and Tecticornia indica (Willd.) subsp. indica were grown with 0, 200, or 400 mM NaCl for 13 weeks to investigate whether salt tolerance was related to maintenance of adequate photosynthetic activity and pigment equipment. Both species showed growth optimum at 200 mM NaCl and better tissue hydration under salinity but different photosynthetic response to salinity. CO2 assimilation rate and stomatal conductance of S. portulacastrum were highest at 200 mM NaCl, while in T. indica they decreased with salinity. Pigment content increased under salinity in both species. The de-epoxidation state in S. portulacastrum suggests the need for energy dissipation at 400 mM NaCl, while its salt-induced decline in T. indica, despite the reduced photochemistry, suggests the involvement of adaptive mechanisms other than the xanthophyll cycle

LA GRIPPE A H1N1 : ACTUALITES

Influenza is a seasonal viral infection associated with significant morbidity and mortality. In 2009, a novel H1N1 influenza A virus emerged and has been classified as a pandemic. In contrast to seasonal influenza, severe disease from pandemic H1N1 seems concentrated in older children and young adults, with almost no cases reported in patients older than 60 yrs. Although patients with underlying cardiopulmonary disease remain at risk, most complications have occurred among previously healthy individuals, with obesity and respiratory disease as the strongest risk factors. Pulmonary complications are common. Primary influenza pneumonia occurs most commonly in adults and may progress rapidly to acute lung injury requiring mechanical ventilation. Secondary bacterial infection is more common in children. Staphylococcus aureus, including methicillin-resistant strains, is an important cause of secondary bacterial pneumonia with a high mortality rate. Treatment of pneumonia should include empirical coverage for this pathogen. Neuromuscular and cardiac complications are unusual but may occur.Le virus de la grippe saisonnière peut être associé à une morbidité voire une mortalité significative. Le nouveau réassortant H1N1 est responsable d’une pandémie en 2009. Contrairement à la grippe saisonnière, des complications sévères sont survenues chez les enfants et les adultes âgés de moins de 60 ans, sans maladies sous jacentes. Certaines pathologies augmentent par ailleurs le risque de complications graves notamment l’obésité, les maladies cardio-réspiratoires et les femmes enceintes. La pneumonie virale est une complication redoutable évoluant rapidement vers la détresse respiratoire aigue nécessitant une ventilation mécanique. La surinfection pulmonaire par le staphylocoque résistant à la méthicilline est possible, surtout chez l’enfant. D’autres complication sont possibles notamment neuromusculaires et cardiaque