Generalized backward doubly stochastic differential equations and SPDEs with nonlinear Neumann boundary conditions

In this paper a new class of generalized backward doubly stochastic differential equations is investigated. This class involves an integral with respect to an adapted continuous increasing process. A probabilistic representation for viscosity solutions of semi-linear stochastic partial differential equations with a Neumann boundary condition is given.Comment: Published at http://dx.doi.org/10.3150/07-BEJ5092 in the Bernoulli (http://isi.cbs.nl/bernoulli/) by the International Statistical Institute/Bernoulli Society (http://isi.cbs.nl/BS/bshome.htm

Major G-Quadruplex Form of HIV-1 LTR Reveals a (3 + 1) Folding Topology Containing a Stem-Loop

Nucleic acids can form noncanonical four-stranded structures called G-quadruplexes. G-quadruplex-forming sequences are found in several genomes including human and viruses. Previous studies showed that the G-rich sequence located in the U3 promoter region of the HIV-1 long terminal repeat (LTR) folds into a set of dynamically interchangeable G-quadruplex structures. G-quadruplexes formed in the LTR could act as silencer elements to regulate viral transcription. Stabilization of LTR G-quadruplexes by G-quadruplex-specific ligands resulted in decreased viral production, suggesting the possibility of targeting viral G-quadruplex structures for antiviral purposes. Among all the G-quadruplexes formed in the LTR sequence, LTR-III was shown to be the major G-quadruplex conformation in vitro. Here we report the NMR structure of LTR-III in K+ solution, revealing the formation of a unique quadruplex-duplex hybrid consisting of a three-layer (3 + 1) G-quadruplex scaffold, a 12-nt diagonal loop containing a conserved duplex-stem, a 3-nt lateral loop, a 1-nt propeller loop, and a V-shaped loop. Our structure showed several distinct features including a quadruplex-duplex junction, representing an attractive motif for drug targeting. The structure solved in this study may be used as a promising target to selectively impair the viral cycle

Optimal Multi-Modes Switching Problem in Infinite Horizon

This paper studies the problem of the deterministic version of the Verification Theorem for the optimal m-states switching in infinite horizon under Markovian framework with arbitrary switching cost functions. The problem is formulated as an extended impulse control problem and solved by means of probabilistic tools such as the Snell envelop of processes and reflected backward stochastic differential equations. A viscosity solutions approach is employed to carry out a finne analysis on the associated system of m variational inequalities with inter-connected obstacles. We show that the vector of value functions of the optimal problem is the unique viscosity solution to the system. This problem is in relation with the valuation of firms in a financial market

Etude du comportement de ponte du carpocapse (Cydia pomonella L.) (Lepidoptera ; Tortricidae) sur deux varietes de pommier (Malus domestica BORKH.)

Le carpocapse, Cydia pomonella L. (Lepidoptera : Tortricidae) figure parmi les principaux ravageurs des pommes et des poires dans la région de  Batna (Algérie). Le présent travail montre la première étude, à l’échelle nationale, sur le comportement de ponte de ce ravageur. La souche  utilisée a été récupérée d’un verger situé dans la région de Tazoult  (Batna). Le choix de deux variétés de pommier (Golden Delicious et Starkrimson), du point de vue de la ponte en conditions naturelles et le choix de la région de Tazoult, réside dans le fait que dans cette région, ces deux variétés sont sensibles au carpocapse. L’observation du comportement de ponte du carpocapse sur arbre, en milieu naturel et en conditions de non-choix dans la région de Limbiridi (Batna), confirme que la variété Golden Delicious est plus sensible à la ponte que la variété Starkrimson. Différentes étapes comportementales sont observées sur les deux variétés étudiées : atterrissage à la surface du pommier, visite des différents sites, examen du site et l’acceptation de ponte. La ponte est accompagnée par l’examen du site par balayage de l’ovipositeur.Mots-clés : Lepidoptera, Cydia pomonella, Golden Delicious, Starkrimson, comportement de ponte. The codling moth, Cydia pomonella L. (Lepidoptera : Tortricidae) is the major pest of apples and pears in the region of Batna (Algeria). This work is the first nationally study about codling moth egg-laying behavior.  Insects used in the study have been collected from the region of Tazoult (Batna). Counting eggs on the two apple tree varieties (Golden Delicious and Starkrimson) in choice conditions in the region of Tazoult (Batna) showed that both varieties are susceptible to codling moth egg-laying, with a slight preference of Golden Delicious. The observation of egg-laying behavior of codling moth on trees in natural and non-choice conditions in the region of Limbiridi (Batna), confirmed that Golden Delicious variety is more preferred for egg-laying than Starkrimson. Different behavioural steps are observed on both studied varieties : landing on the surface of apple tree, visiting different sites, site examination and acceptance of egg-laying. The egglaying is accompanied by an examination of the site by scanning of the ovipositor.Key words : Lepidoptera, Cydia pomonella, Codling moth, Golden  Delicious, Starkrimson, egg-laying behavior

Mitigation of voltage imbalance in power distribution system using MPC-controlled packed-U-cells converter

Delivering high power quality in single-phase distribution has witnessed more challenges especially with the increased penetration of single-phase distributed generation (DG). This paper proposes a smart solid-state-based transformer, which aims to replace traditional ones, for single-phase distribution laterals, and provide load balancing and protection to the three-phase main feeders, that is based on connecting the single-phase lateral to the three-phase main feeder through a power electronics converter. This converter transfers balanced power from and to the three-phase feeder while automatically regulating the lateral single-phase voltage, hence, assuring high power quality without requiring any transformer on-load tap changer. A 7-level packed-U-cells (PUC) single-phase inverter topology was used to deliver single-phase regulated sinusoidal voltage to the AC loads, and at the same time, it is able to deliver DC power to DC loads. The simulation and hardware-in-the-loop (HIL) results have shown that the proposed topology delivers high power quality for both AC and DC loads under different operating scenarios. Moreover, the converter can play the role of a solid-state protection device coordinated with other up- and downstream protective devices. Finally, this system can be integrated within the smart grid allowing more flexibility for automation and efficient control of the grid. - 2019 The Authors. Energy Science & Engineering published by the Society of Chemical Industry and John Wiley & Sons Ltd.This work was made possible by Qatar University Internal Grant no. QUCP?CENG?EE?15/16?4

Behavior of the parameters of microcrystalline silicon TFTs under mechanical strain

International audienceN-type and P-type microcrystalline silicon top-gate TFTs, processed directly on PEN plastic substrate at maximum temperature of 180 °C, were mechanically stressed. These TFTs were bent by different curvature radii varying between infinite (flat) and 0.5 cm. The tensile stress increases the electron mobility and the compressive stress decreases it. The tensile stress decreases the threshold voltage of N-type TFTs while the compressive stress increases it. These trends are inversed if the type of stress changes OR the type of TFTs changes. The total behavior under mechanical stress is exactly similar to that of single crystalline silicon MOSFETs in nano-scale technologies (90, 65, 45, 32 nm), where nano-scale stress is introduced in the goal to engineer the electrical parameters. The similarity originates from the microcrystalline silicon active layer that behaves like single crystalline silicon even if the stress effects are softened by the grain boundaries and the multiple crystalline orientations of the grains

Determination of residence time distribution and axial dispersion coefficient in a meso-scale oscillatory baffled crystallizer using a computational fluid dynamics approach [Abstract]

Determination of residence time distribution and axial dispersion coefficient in a meso-scale oscillatory baffled crystallizer using a computational fluid dynamics approach [Abstract

Characterisation of axial dispersion in a meso-scale oscillatory baffled crystalliser using a numerical approach. [Abstract]

Characterisation of axial dispersion in a meso-scale oscillatory baffled crystalliser using a numerical approach. [Abstract

Early-career paleoscientists meet in the mountains of Aragon

Three days prior to the 5th PAGES Open Science Meeting (OSM), 80 ambitious early-career scientists (PhD students and postdoctoral researchers) met in the restored village of Morillo de Tou, Spain. The remote setting in the Pyrenees, the old style buildings constructed of turbidites, and the clear and sunny weather made this place an inspiring location to discuss past climate, environment and human interactions. Despite some grumblings about cold coffee served in small cups, the conference was a high-energy affair that promoted connections