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Riga, Latvia

University of Latvia is a university located in Riga, Latvia. Established in 1919, University of Latvia is the largest university in the Baltic states. The university is ranked 701st – 750th in the world. Wikipedia.

Advanced therapy medicinal products (ATMPs), including cell therapy products, form a new class of medicines in the European Union. Since the ATMPs are at the forefront of scientific innovation in medicine, specific regulatory framework has been developed for these medicines and implemented from 2009. The Committee for Advanced Therapies (CAT) has been established at the European Medicines Agency (EMA) for centralized clas- sification, certification and evaluation procedures, and otherATMP-related tasks. Guidance documents, initiatives, and interaction platforms are available to make the new framework more accessible for small- and medium-sized enterprises, academia, hospitals, and foun- dations. Good understanding of the centralized and national components of the regulatory system is required to plan product development. It is in the best interests of the cell ther- apy developers to utilize the resources provided starting with the pre-clinical stage.Whilst there have been no mesenchymal stem cell (MSC)-based medicine authorizations in the EU, three MSC products have received marketing approval in other regions since 2011.The information provided on the regulatory requirements, procedures, and initiatives is aimed at facilitating MSC-based medicinal product development and authorization in the EU. © 2012 Ancans. Source

Ambainis A.,University of Latvia
Proceedings of the Annual ACM Symposium on Theory of Computing | Year: 2013

A quantum algorithm is exact if, on any input data, it outputs the correct answer with certainty (probability 1). A key question is: how big is the advantage of exact quantum algorithms over their classical counterparts: deterministic algorithms. For total Boolean functions in the query model, the biggest known gap was just a factor of 2: PARITY of N input bits requires N queries classically but can be computed with ⌈N/2⌉ queries by an exact quantum algorithm. We present the first example of a Boolean function f(x1, ..., xN) for which exact quantum algorithms have superlinear advantage over deterministic algorithms. Any deterministic algorithm that computes our function must use N queries but an exact quantum algorithm can compute it with O(N0.8675...) queries. A modification of our function gives a similar result for communication complexity: there is a function f which can be computed by an exact quantum protocol that communicates O(N0.8675...) quantum bits but requires Ω(N) bits of communication for classical protocols. Copyright 2013 ACM. Source

In this paper, the review of recent results of calculations of surface relaxations, energetics, and bonding properties for ABO3 perovskite (001), (011) and (111) surfaces using mostly a hybrid description of exchange and correlation is presented. Both AO and BO2-terminations of the nonpolar (001) surface and A, BO, and O terminations of the polar (011) surface, as well as B and AO3-terminations of the polar (111) surface were considered. On the AO-terminated (001) surface, all upper-layer A atoms relax inwards, while all second layer atoms relax outwards. For the BO 2-terminated (001) surface, in most cases, the largest relaxations are on the second-layer metal atoms. For almost all ABO3 perovskites, the surface rumpling is much larger for the AO-terminated than for the BO 2-terminated (001) surface, but their surface energies are always quite similar. In contrast, different terminations of the (011) ABO3 surface lead to very different surface energies for the O-terminated, A-terminated, and BO-terminated (011) surface, respectively. A considerable increase in the Ti-O or Zr-O, respectively, chemical bond covalency near the (011) surface as compared both to the bulk and to the (001) surface in ABO 3 perovskites were predicted. According to the results of ab initio calculations for Nb doped SrTiO3, Nb is a shallow donor; six nearest O ions are slightly displaced outwards from the Nb ion. The F center in ABO 3 perovskites resembles electron defects in the partially-covalent SiO2 crystal rather than usual F centers in ionic crystals like MgO and alkali halides. The results of calculations for several perovskite KNb xTa1-xO3 (KTN) solid solutions, as well as hole and electron polarons in ABO3 perovskites are analyzed. © World Scientific Publishing Company. Source

Kaestner B.,University of Latvia | Kashcheyevs V.,Physikalisch - Technische Bundesanstalt
Reports on Progress in Physics | Year: 2015

Precise manipulation of individual charge carriers in nanoelectronic circuits underpins practical applications of their most basic quantum propertythe universality and invariance of the elementary charge. A charge pump generates a net current from periodic external modulation of parameters controlling a nanostructure connected to source and drain leads; in the regime of quantized pumping the current varies in steps of qe f as function of control parameters, where qe is the electron charge and f is the frequency of modulation. In recent years, robust and accurate quantized charge pumps have been developed based on semiconductor quantum dots with tunable tunnel barriers. These devices allow modulation of charge exchange rates between the dot and the leads over many orders of magnitude and enable trapping of a precise number of electrons far away from equilibrium with the leads. The corresponding non-adiabatic pumping protocols focus on understanding of separate parts of the pumping cycle associated with charge loading, capture and release. In this report we review realizations, models and metrology applications of quantized charge pumps based on tunable-barrier quantum dots. © 2015 IOP Publishing Ltd. Source

Belovs A.,University of Latvia
Proceedings - Annual IEEE Symposium on Foundations of Computer Science, FOCS | Year: 2012

We present a quantum algorithm solving the k-distinctness problem in a less number of queries than the previous algorithm by Ambainis. The construction uses a modified learning graph approach. Compared to the recent paper by Belovs and Lee, the algorithm doesn't require any prior information on the input, and the complexity analysis is much simpler. © 2012 IEEE. Source

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