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Vilnius, Lithuania

The Lithuanian Academy of science or LAS, founded in 1941 as the Lithuanian SSR Academy of science , as an autonomous, state-subsidized establishment serving as a scientific advisory body to the government of Lithuanian SSR. Following the 1991 passage of the Law on Research and Higher Education of the Republic of Lithuania, it was reorganized. Its first president was Vincas Krėvė-Mickevičius, followed by Mykolas Biržiška, Vladas Jurgutis, Juozas Matulis, Juras Požela, Benediktas Juodka, and Zenonas Rokus Rudzikas. The Academy represents the Republic of Lithuania in the following international organizations: ALLEA , ICSU , EASAC , and IAP . In addition to founding several scientific institutions and foundations, it issues publications and textbooks, sponsors symposia and conferences. It has established 15 memorial prizes and awards, encourages young scientists and students to engage in research by annually awarding 10 prizes to young scientists and 15 prizes to students. Since 2008 together with the Bank of Lithuania grants Vladas Jurgutis Award.The Academy's headquarters are located in Vilnius. Wikipedia.

Zubovas K.,Lithuanian Academy of Sciences | Nayakshin S.,University of Leicester
Monthly Notices of the Royal Astronomical Society | Year: 2014

It is usually assumed that outflows from luminous active galactic nuclei (AGN) are either in the energy-conserving (non-radiative) or in the momentum-conserving (radiative) regime. We show that in a non-spherical geometry the effects of both regimes may manifest at the same time, and that it is the momentum of the outflow that sets the MBH-σ relation. Considering an initially elliptical distribution of gas in the host galaxy, we show that a non-radiative outflow opens up a wide 'escape route' over the paths of least resistance. Most of the outflow energy escapes in that direction. At the same time, in the directions of higher resistance, the ambient gas is affected mainly by the incident momentum from the outflow. Quenching SMBH growth requires quenching gas delivery along the paths of highest resistance, and therefore, it is the momentum of the outflow that limits the black hole growth. We present an analytical argument showing that such energy-conserving feedback bubbles driving leaky ambient shells will terminate SMBH growth once its mass reaches roughly the Mσ mass derived earlier by King for momentum-conserving AGN outflows. Our simulations also have potentially important implications for observations of AGN jet feedback and starburst galaxy feedback. The collimation of the wide angle AGN outflow away from the symmetry plane, as found in our simulations, indicates that credit for work done by such outflows may sometimes be mistakenly given to AGN jets or star formation feedback since wide angle ν ~ 0.1c outflows are harder to observe and the phase when they are present may be short. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Zubovas K.,Lithuanian Academy of Sciences | King A.R.,University of Leicester
Monthly Notices of the Royal Astronomical Society | Year: 2014

Several active galaxies show strong evidence for fast (vout ~ 1000 km s-1) massive (M= several × 1000 M⊙yr-1) gas outflows. Such outflows are expected on theoretical grounds once the central supermassive black hole reaches the mass set by the M-σ relation, and may be what makes galaxies become red and dead. Despite their high velocities, which imply temperatures far above those necessary for molecule dissociation, the outflows contain large amounts of molecular gas. To understand this surprising result, we investigate the gas cooling and show that the outflows cannot stably persist in high-temperature states. Instead, the outflowing gas forms a two-phase medium, with cold dense molecular clumps mixed with hot tenuous gas, as observed. We also show that efficient cooling leads to star formation, providing an observable outflow signature. The central parts of the outflows can be intrinsically luminous gamma-ray sources, provided that the central black hole is still strongly accreting. We note also that these outflows can persist for ~108 yr after the central AGN has turned off, so that many observed outflows (particularly with high speeds) otherwise assumed to be driven by starbursts might also be of this type. © 2014 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society.

Zilinskas A.,Lithuanian Academy of Sciences
Journal of Global Optimization | Year: 2010

Construction of global optimization algorithms using statistical models and radial basis function models is discussed. A new method of data smoothing using radial basis function and least squares approach is presented. It is shown that the P-algorithm for global optimization in the presence of noise based on a statistical model coincides with the corresponding radial basis algorithm. © 2009 Springer Science+Business Media, LLC.

Raudys S.,Vilnius University | Raudys A.,Lithuanian Academy of Sciences
IEEE Transactions on Pattern Analysis and Machine Intelligence | Year: 2010

A novel loss function to train a net of K single-layer perceptrons (KSLPs) is suggested, where pairwise misclassification cost matrix can be incorporated directly. The complexity of the network remains the same; a gradient's computation of the loss function does not necessitate additional calculations. Minimization of the loss requires a smaller number of training epochs. Efficacy of cost-sensitive methods depends on the cost matrix, the overlap of the pattern classes, and sample sizes. Experiments with real-world pattern recognition (PR) tasks show that employment of novel loss function usually outperforms three benchmark methods. © 2010 IEEE.

Cicenas J.,University of Fribourg | Valius M.,Lithuanian Academy of Sciences
Journal of Cancer Research and Clinical Oncology | Year: 2011

Chemical compounds that interfere with an enzymatic function of kinases are useful for gaining insight into the complicated biochemical processes in mammalian cells. Cyclin-dependent kinases (CDK) play an essential role in the control of the cell cycle and/or proliferation. These kinases as well as their regulators are frequently deregulated in different human tumors. Aberrations in CDK activity have also been observed in viral infections, Alzheimer's, Parkinson's diseases, ischemia and some proliferative disorders. This led to an intensive search for small-molecule CDK inhibitors not only for research purposes, but also for therapeutic applications. Here, we discuss seventeen CDK inhibitors and their use in cancer research or therapy. This review should help researchers to decide which inhibitor is best suited for the specific purpose of their research. For this purpose, the targets, commercial availability and IC50 values are provided for each inhibitor. The review will also provide an overview of the clinical studies performed with some of these inhibitors. © 2011 Springer-Verlag.

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