Mining evolving data streams for frequent patterns

A data stream is a potentially uninterrupted flow of data. Mining this flow makes it necessary to cope with uncertainty, as only a part of the stream can be stored. In this paper, we evaluate a statistical technique which biases the estimation of the support of patterns, so as to maximize either the precision or the recall, as chosen by the user, and limit the degradation of the other criterion. Theoretical results show that the technique is not far from the optimum, from the statistical standpoint. Experiments performed tend to demonstrate its potential, as it remains robust even under significant distribution drifts.     

Multiparametric analysis within the proper generalized decomposition framework

Optimization campaigns, which are being launched more and more often, require the execution of many parametric studies which can make the approach very costly in terms of computation time. Here, in order to reduce these computation times, we undertake to develop a multiparametric strategy using the LATIN method along with Proper Generalized Decomposition. This approach is compared to other common strategies, especially those based on POD.     

Dynamic Combinatorial Chemistry in Chemical Catalysis

Despite the progress in the field of dynamic combinatorial chemistry (DCC), dynamic combinatorial catalysis has received considerably less attention. Some first studies, however, have provided proof of principle and demonstrated that DCC-based approaches are also applicable in catalyst development. This provides interesting new tools that are complementary to rational catalyst design and traditional combinatorial strategies. As such, DCC may become highly valuable in the field of dynamic combinatorial catalysis, due also to the practical importance of catalysis. In this review we focus on the principles of dynamic combinatorial catalysis and provide an overview by the introduction of different concepts related to the development of libraries and selection procedures in catalysis.     

Constraint based approach for the steady-state simulation of complex systems: Application to ship control

When the steady states are largely predominant with respect to transitional phases, steady-state simulation seems sufficient to predict the behavior of a complex system. Over the past 20 years, different modeling languages and dedicated tools have been developed to improve steady state simulation.In this paper, focus is made on steady-state simulation for system control and design. A model combining an emission sub-model with a ship propulsion sub-model was implemented in a constraint programming (CP) approach. It will help to determine the efficiency (i.e. the ability to model and solve the problem) and complexity of implementation (i.e. difficulties encountered during the implementation) of this approach.First, requirements for the steady-state simulation of complex systems are defined. Then, CP approach is shown to be able to answer these issues through experiments. This approach is then compared to one of the main simulation languages: Modelica.Although the two approaches (i.e Modelica and CP) are able to reverse models, the study shows that the use of Modelica principles for steady-state simulation involves some crippling limitations, such as the non-management of under/over-constrained systems, or inequalities.This study also shows that the constraint programming approach permits to meet some needs for steady-state simulation not yet covered by current approaches.     

Functional EGFP-dystrophin fusion proteins for gene therapy vector development

Transfection and transduction studies involving the use of thefull-length dystrophin (11 kb) or the truncated mini-gene (6kb) cDNAs are hampered by the large size of the resulting viralor non-viral expression vectors. This usually results in verylow yields of transgene-expressing cells. Moreover, the detectionof the few transgene-expressing cells is often tedious and costly.For these reasons, expression vectors containing the enhancedgreen fluorescent protein (EGFP) fused with the N-termini ofmini- and full-length human dystrophin were constructed. Theseconstructs were tested by transfection of Phoenix cells withEffectene, resulting after 48 h in a green fluorescent signalin 20% of cells. Analysis of the cell extracts by immunoblottingwith the use of a monoclonal antibody specific to the dystrophinC-terminus confirmed the expression of EGFP–mini- (240kDa) and EGFP–full-length human dystrophin (450 kDa) fusionproteins. Moreover, following the in vivo electroporation ofthe plasmids containing the EGFP–mini- and full-lengthdystrophin in mouse muscles, both fluorescent proteins wereobserved in cryostat sections in their normal location underthe plasma membrane. This indicates that the fusion of EGFPto dystrophin or mini-dystrophin did not interfere with thenormal localization of the protein. In conclusion, the fusionof EGFP provides a good tool for the search of the best methodsto introduce mini- or full-length dystrophin cDNA in the cells(in vitro) or muscle fibers (in vivo) for the establishmentof a treatment by gene therapy of Duchenne muscular dystrophypatients.     

Activity and thermal stability of antioxidants by differential scanning calorimetry and electron spin resonance spectroscopy

Heat flux differential scanning calorimetry (DSC) and electron spin resonance spectroscopy (ESR) were used to assess the activity and the thermal stability of antioxidants in four vegetable oils. Sunflower oil (SO) and high oleic sunflower oil (HOSO), both rich in diunsaturated fatty acids (FA), low trans oil (LT) and partially hydrogenated palm oil (PHPO), both containing monounsaturated FA, were analyzed by isothermal heat flux DSC, with or without 300 mg/kg of antioxidant: ascorbyl palmitate (AP), α-tocopherol (αT), δ-tocopherol (δT) and propyl gallate (PG). DSC experiments showed that δT is the most effective antioxidant for SO and PG for the less unsaturated oils. SO and PHPO were also analyzed by ESR at 120 and 145 °C, respectively. ESR results confirm the strongest antioxidant activity of δT and PG for SO and PHPO, respectively. Therefore, the present study demonstrates that DSC and ESR are valuable technologies to study activity and stability of antioxidants at high temperature. Moreover, experiments performed in the presence of the spin-trap N-tert-butyl-α-phenylnitrone (PBN), suggest that δT delay lipid oxidation through a different reaction mechanism when compared to αT. A different mechanism between tocopherols isomers in delaying lipid oxidation has been hypotized.     

Using 3D modeling and remote sensing capabilities for a better understanding of spatio-temporal heterogeneities of phytoplankton abundance in large lakes

Lake biological parameters show important spatio-temporal heterogeneities. This is why explaining the spatial patchiness of phytoplankton abundance has been a recurrent ecological issue and is an essential prerequisite for objectively assessing, protecting and restoring freshwater ecosystems. The drivers of these heterogeneities can be identified by modeling their dynamics. This approach is useful for theoretical and applied limnology. In this study, a 3D hydrodynamic model of Lake Geneva (France/Switzerland) was created. It is based on the Delft3D suite software and includes the main tributary (Rhône River) and two-dimensional high-resolution meteorological forcing. It provides 3D maps of water temperature and current velocities with a 1?h time step on a 1?km horizontal grid size and with a vertical resolution of 1?m near the surface to 7?m at the bottom of the lake. The dynamics and the drivers of phytoplankton heterogeneities were assessed by combining the outputs of the model and chlorophyll-a concentration (Chl-a) data from MERIS satellite images between 2008 and 2012. Results highlight physical mechanisms responsible for the occurrence of seasonal hot-spots in phytoplankton abundance in the lake. At the beginning of spring, Chl-a heterogeneities are usually caused by an earlier onset of phytoplankton growth in the shallowest and more sheltered areas; spatial differences in the timing of phytoplankton growth can be explained by spatial variability in thermal stratification dynamics. In summer, transient and locally higher phytoplankton abundances are observed in relation to the impact of basin-scale upwelling.     

Key-Recovery Attacks on <Emphasis FontCategory="SansSerif">ASASA</Emphasis>

The \(\mathsf {ASASA}\) construction is a new design scheme introduced at Asiacrypt 2014 by Biryukov, Bouillaguet and Khovratovich. Its versatility was illustrated by building two public-key encryption schemes, a secret-key scheme, as well as super S-box subcomponents of a white-box scheme. However, one of the two public-key cryptosystems was recently broken at Crypto 2015 by Gilbert, Plût and Treger. As our main contribution, we propose a new algebraic key-recovery attack able to break at once the secret-key scheme as well as the remaining public-key scheme, in time complexity \(2^{63}\) and \(2^{39}\), respectively (the security parameter is 128 bits in both cases). Furthermore, we present a second attack of independent interest on the same public-key scheme, which heuristically reduces the problem of breaking the scheme to an \(\mathsf {LPN}\) instance with tractable parameters. This allows key recovery in time complexity \(2^{56}\). Finally, as a side result, we outline a very efficient heuristic attack on the white-box scheme, which breaks instances claiming 64 bits of security under one minute on a laptop computer.     

Ultrasensitive PCR and real-time detection from human genomic samples using a bidirectional flow microreactor

In this paper we present a reliable bidirectional flow DNA amplification microreactor for processing real-world genomic samples. This system shares the low-power thermal responsiveness of a continuous flow reactor with the low surface area to volume ratio character of stationary reactors for reducing surface inhibitory effects. Silanization with dimethyldichlorosilane in combination with dynamic surface passivation was used to enhance PCR compatibility and enable efficient amplification. For real-time fragment amplification monitoring we have implemented an epimodal fluorescent detection capability. The passivated bidirectional flow system was ultrasensitive, achieving an RNase P gene detection limit of 24 human genome copies with a reaction efficiency of 77%. This starts to rival the performance of a conventional real-time PCR instrument with a reaction efficiency of 93% and revitalizes flow-through PCR as a viable component of lab on a chip DNA analysis formats.