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Yayın Spectral renormalization group for the Gaussian model and 𝜓4 theory on nonspatial networks(American Physical Society, 2015-08-06) Tuncer, Aslı; Erzan, AyşeWe implement the spectral renormalization group on different deterministic nonspatial networks without translational invariance. We calculate the thermodynamic critical exponents for the Gaussian model on the Cayley tree and the diamond lattice and find that they are functions of the spectral dimension, (d) over tilde. The results are shown to be consistent with those from exact summation and finite-size scaling approaches. At (d) over tilde = 2, the lower critical dimension for the Ising universality class, the Gaussian fixed point is stable with respect to a psi(4) perturbation up to second order. However, on generalized diamond lattices, non-Gaussian fixed points arise for 2 < <(d)over tilde> < 4.Yayın Strategies for the evolution of sex(American Institute of Physics Inc., 2001-12) Tüzel, Erkan; Sevim, Volkan; Erzan, AyşeThe maintenance of a macroscopic sexual population is addressed. As a scenario, the mechanism of random conversion to sex, in the presence of a constant rate of mutation is examined. This scenario is very closely related to "coevolution of cell senescence and diploid sexual reproduction in unicellular organisms." In this work, a "senescence clock" ticks off a finite lifetime for each bit string. Sexual reproduction resets the senescence of clock; unless this happens after a number of generations of cloning, the offspring stop dividing and die.Yayın Theoretical calculation of the kinetic coefficient of normal crystal growth(Trans Tech Publications Ltd, 2004) Dimitrov, Ventzislav IvanovAn expression for the velocity u of migration of a diffuse simple crystal-melt interface has been derived on the basis of the theory of atomic mobility in supercooled liquids: u = K-0 (T / T-m) DeltaT, where DeltaT = T-m - T the undercooling below the melting point T-m; K-0 is the kinetic coefficient of atomic attachment, which is used in models of crystal growth. It has been calculated for a number of metals. u(max) = K0Tm / 4 is the theoretical limit of the velocity of crystal growth. For a number of FCC metals the theoretical limit of crystal growth has been found to be of order of 200 m/s. The crystal growth kinetics has been shown to be limited by the atomic self-diffusion in the interface, for which the strong dependence on the orientation of the crystal/melt interface has been explained.Yayın Breakdown of the Stokes-Einstein relation in supercooled liquids(Trans Tech Publications Ltd, 2004) Dimitrov, Ventzislav IvanovBreakdown of the Einstein-Stokes relation in undercooled liquids is one of the unsolved problems in the theory of liquids. The self-diffusion coefficient follows the temperature dependence of the Einstein-Stokes equation D = kT / 6pietar at high temperatures but only down to approximately 1.2T(g) (T-g - glass-temperature). Below 1.2T(g) the temperature behavior of the diffusion coefficient is weaker than 1/eta. In the present study we show that this is a consequence of increasing correlations in the Brownian motion of the constituting particles of the liquid. We derive a relation, which includes the Einstein-Stokes equation as a limiting case for high temperatures.Yayın Calix[4]amine Langmuir-Blodgett thin film sensing properties against volatile organic compounds(IOP Publishing LTD, 2019) Şen, Sibel; Çapan, Rifat; Özbek, Zikriye; Özel, Mehmet Emin; Stanciu, Gheorghe A.; Davis, FrankThin films of CBAMINE were deposited at air-water interface by the method of Langmuir-Blodgett (LB) technique onto a suitable substrate. Atomic force microscopy technique was used to characterize its thin film properties. The results indicate that a uniform LB film monolayer from the water surface to a glass or quartz crystal substrates deposited with a transfer ratio of over 96 %. Gas sensing properties and thickness of the LB thin films of CBAMINE were investigated using Surface plasmon resonance (SPR) technique. Its vapour sensing properties were investigated for different volatile organic compounds. Reversible changes in the optical behaviour were observed and thin films of this material are highly selective for chloroform vapour with fast response and recovery times.Yayın Studying on the small molecule diffusion into hydrogels: a fluorescence study(Amer Inst Physics, 2007) Evingür, Gülşen Akın; Karslı, Kadir; Pekcan, Mehmet ÖnderIn situ steady state fluorescence experiments (SSF) were reported during the diffusion of water molecules into PAAm in gels at various temperatures. The fluorescence emission intensities, Ip increased continuously as water molecules diffused into gels. I-sc, scattered light intensities, from the gel was also monitored to detect the variation in the gel structure during diffusion process. Swelling and diffusion experiments were quantified by Li-Tanaka and Fickian models.Yayın Structure and expression analyses of the Fertilization Independent Seed (FIS) gene orthologs of the apomict Boechera species(Society for Biology and Biotechnology, 2015) Yılmaz, Sibel; Gözükırmızı, Nermin; Scott, Rod John; Taşkın, Kemal MelihIn this study Arabidopsis thaliana Fertilization Independent Seed 2 (FIS2) and Fertilization Independent Endosperm (FIE) genes orthologs were analysed in pseudogamous apomict and sexual Boechera species. FIS genes encode Polycomb Group (PcG) proteins that form a complex. Some mutant alleles of these genes produce endosperm like structure even in the absence of fertilization in A. thaliana. Therefore, the function of FIS complex known as to represses endosperm development prior to fertilization and plays an important role in regulating the endosperm development following fertilization. However, little is known about how apomicts have develop embryo without fertilization and adjusted endosperm development to cope with parental genome imbalance that results from non-reduction of maternal gametes. Therefore, the sexual and apomict Boechera species, as a close relative of A. thaliana, provide an attractive opportunity to investigate FIS function in pseudogamous apomicts. In this study, we report the full length genomic sequences of the apomict B. holboellii FIS2 and FIE through the mapping of the B. holboellii short-paired reads library, by using A. thaliana FIS genes as the reference sequences. We also obtained the genomic sequences of FIS2 and FIE from the sexual species B. stricta sequenced genome using the Phytozome 10.2. Then, we used these sequences to design primers and cDNAs were amplified by Reverse Transcriptase PCR. Full length cDNA of Boechera FIE transcript was 1110 bp and share 99% sequence similarity with AtFIE. Boechera FIS2 was 2188 bp and have 83% similarity with AtFIS2. The multiple alignment and phylogenetic analyses suggested that while FIE are highly conserved among Brassicacea, FIS2 is variable and also diverged from A. thaliana. In addition to sequence analyses we also investigated expression of FIE and FIS2 transcript in various tissues and they were observed in all tissues tested. These results indicated that FIE and FIS2 genes may play a role in the regulation of endosperm development in pseudogamous apomicts with diverse way from sexual relatives.Yayın Electrochromic switching of WO3 nanostructures and thin films(Springer-Verlag, 2006-04) Karakurt, İsmail; Boneberg, Johannes; Leiderer, PaulWe present transmission measurements through tungsten tri-oxide nanostructures and thin films prepared by sol-gel process on micro-contact printed substrates. Identical electrochromic switching times are found for both the nanostructures and the bulk films with equal thicknesses upon intercalation of H+ ions. We attribute the large change in the transmission through nanostructures at 632 nm, which can not be solely explained by absorption, to diffraction effects.Yayın Technical climate change adaptation options of the major ski resorts in Bulgaria(Springer International Publishing, 2016-01-01) Demiroğlu, Osman Cenk; Turp, Mustafa Tufan; Öztürk, Tuğba; An, Nazan; Kurnaz, Mehmet LeventClimate change has been and increasingly will be a major threat to the ski tourism industry, whose survival is highly dependent on the existence of snow cover of sufficient depth and duration. For this matter, it is even now more usual for the ski resorts to adapt to this issue by various measures at the technical, operational, and political levels. Technically speaking, snowmaking has become the method most used throughout the industry to combat the immediate impacts of climate change, while moving the ski areas to higher terrains has been standing out as an another option, wherever available and feasible. In this study, the aim is to project the future climatic changes in snowmaking capacity; in other words, technical snow reliability, and the moving requirements, if any, of the four major ski resorts in Bulgaria for the period of 2016-2030 with respect to the control period of 1991- 2005. For this purpose, the past and the future climatic conditions for the technical snow reliability of the ski resorts and their immediate surroundings are determined by the temperature and the relative humidity values generated and projected through the Regional Climate Model RegCM 4.4 of the Abdus Salam International Centre for Theoretical Physics (ICTP) by scaling the global climate model MPI-ESM-MR of Max Planck Institute for Meteorology down to a resolution of 10 km. The model is further processed according to the recent RCP 4.5 and RCP 8.5 concentration scenarios of the IPCC. The model outputs on air temperature and relative humidity are utilized for determination of wet-bulb temperatures through psychographic conversions that ultimately provide us with thresholds for snowmaking limits. Findings display the temporal changes in the snowmaking hours of the ski resorts at various altitudinal levels calculated according to the environmental lapse rates. Such displays can guide the practitioners in considering investment lives and moving the ski resorts according to optimistic and pessimistic projections.Yayın Strategies for the evolution of sex(American Physical Soc, One Physics Ellipse, 2001-12) Tüzel, Erkan; Sevim, Volkan; Erzan, AyşeWe find that the hypothesis made by Jan, Stauffer, and Moseley [Theory Biosci. 119, 166 (2000)] for the evolution of sex, namely, a strategy devised to escape extinction due to too many deleterious mutations, is sufficient but not necessary for the successful evolution of a steady state population of sexual individuals within a finite population. Simply allowing for a finite probability for conversion to sex in each generation also gives rise to a stable sexual population, in the presence of an upper limit on the number of deleterious mutations per individual. For large values of this probability, we find a phase transition to an intermittent, multistable regime. On the other hand, in the limit of extremely slow drive. another transition takes place to a different steady state distribution. with fewer deleterious mutations within the population.
