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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 A mean field model near the NAC point in liquid crystals(Physical Soc Republic China, 2002-10) Enginer, Yücel; Salihoğlu, Selami; Yurtseven, HamitIn this study we obtain the phase line equations for the nematic-smectic A (NA), smectic A-smectic C (AC) and nematic-smectic C (NC) transitions using a mean field model. We fit these phase line equations to the experimental phase diagram near the Nenatic-smectic A-smectic C (NAC) point. Our calculated phase diagram agrees well with the experimental.Yayın Fluctuation theory of the liquid-glass transition(Trans Tech Publications Ltd, 2004) Dimitrov, Ventzislav IvanovThe glassy state and the character of the liquid-glass transition from undercooled liquid to amorphous solid is one of the biggest challenges of our time. In spite of significant progress we still cannot explain accurately the sudden solidification of undercooled liquids on the atomic scale. In the present paper we present an analytical theory of the dependence of the glass transition temperature on the rate of cooling: the glass transition temperature increases with increasing cooling rate but does not exceed some upper limit. At almost zero cooling rates (hypothetical reversible transformation of the liquid into glass) the glass transition temperature reduces to a critical temperature, similar to a phase transition temperature.Yayın Projections for changes in natural and technical snow reliability of a major Turkish ski resort by using RegCM4.3.5(European Geosciences Union (EGU), 2014-05-02) Öztürk, Tuğba; Demiroğlu, Osman Cenk; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventClimate change has been and increasingly will be a major threat to the ski tourism industry whose survival is highly dependent on existence of snow cover of sufficient depth and duration. The common knowledge requires that in order for a ski resort to be viable, it has to perform operations for at least 100 days in seven out of ten winters. For this matter, it is now even more usual for the ski resorts to adapt to this issue by technical snowmaking. In this study, projected future changes for the period of 2010-2040, 2040-2070, and 2070-2100 in air temperature, relative humidity, and snow depth climatology and variability with respect to the control period of 1970-2000 were assessed for the domain of a major ski resort in Turkey. Regional Climate Model (RegCM4.3.5) of ICTP (International Centre for Theoretical Physics) was used for projections of future and present climate conditions. HadGEM2 global climate model of the Met Office Hadley Centre, MPI-ESM-MR of the Max Planck Institute for Meteorology, GFDL-ESM2M of the National Oceanic and Atmospheric Administration Geophysical Fluid Dynamics Laboratory were downscaled to 10 km for the resort and its surrounding region. Both the projections and the downscaling were realized according to the RCP4.5 and the RCP8.5 emission scenarios of the IPCC. The outputs on snow depth were used for a count of the changes on snow cover duration sufficient for skiing actitivies, signaling natural snow-reliability, whereas the outputs on air temperature and relative humidity were utilized for determination of wet-bulb temperatures. The latter measure was used to interpret the changes in the snowmaking capacity, in other words; technical snow-reliability, of the resort.Yayın A refined methodology for modelling climate change impacts on snow sports tourism(European Geosciences Union (EGU), 2015-04-17) Demiroğlu, Osman Cenk; Turp, Mustafa Tufan; Öztürk, Tuğba; An, Nazan; Kurnaz, Mehmet LeventNature-based tourism is one of the most vulnerable sectors of the economy against climate change. Among its types, winter tourism stands out as the most critical due to the relatively high exposure and sensitivity of snow cover to the anthropogenic warming trends. In this study, we aim at improving previous works by Ozturk et al. where snow reliability of ski resorts have been examined through projections based on regional climate model outputs downscaled from various GCMs. Major improvements to these studies will be related to increasing the resolution, obtaining snow depth values from snow-water equivalent outputs, and hourly, instead of the daily, calculations of wet bulb temperatures. Daily snow depth values will be utilized for 100-days rule that looks for at least 100 days of snow cover at a minimum of 30 cm in order for a ski resort to be viable, whereas the wet bulb temperatures below -7 oC will indicate the snowmaking capacity. The domain of analysis will be the Balkans, the Middle East and the Caucasus. Therefore the spatial gap in the mostly Euro- and Amero-centric literature will also be improved. The domain will be modelled through RegCM 4.4.2 of the International Centre for Theoretical Physics basing its resolution on MPI-ESM-MR of Max Planck Institut für Meteorologie and the concentration scenario RCP 4.5 for a realistic tourism development future of 2020-2050.Yayın Climate change versus 'security and peace' in the Mediterranean macroclimate region: are they correlated?(Coventry University, 2011-10-28) Türkeş, Murat; Öztürk, Tuğba; Altınsoy, HamzaClimate change, whether its global or regional scale, is one of the most significant and far-reaching challenges that the human societies living in the Earth’s surface have faced in the 21st century as it was in the 20th century. Consequently, the aim of this study is to scientifically assess impacts of the global and regional climate changes and variability including decreased precipitation amounts (drying) and increased air temperatures (warming) that would very likely cause to increase frequencies, durations and intensities of the drought events in the Mediterranean basin and Turkey, and associated problems and consequences with respect to the global, regional and national peace, prosperity and security issues and concerns.Yayın Case study Turkey: climate changeand coastal tourism: impacts of climate change on the turquoise coast(CAB International, 2017-11-29) Demiroğlu, Osman Cenk; Akbaş, Abdullah; Turp, Mustafa Tufan; Öztürk, Tuğba; An, Nazan; Kurnaz, Mehmet LeventThis chapter tries to assess the severity of expected climate change impacts on tourism at the Turquoise Coast (Turkey) and build up an adaptation agenda for the concerned parties. First, sea level rise projections are considered to understand the degree of exposure at the immediate coastal zone. A storm and flood risk projection follows to visualize any additional risks on the coasts as well as for the nautical tourism routes. A climate model also provides with outputs for determining the changes in the touristic climate comfort as well as spotting any increase of heatwave events. The changing windiness characteristics are also investigated to determine implications for surf tourism. Lastly, an aridity index and water deficit projections are interpreted to understand a conflicting future where water availability could decrease, whereas the growth of the tourism industry, particularly golf tourism, would imply more consumption of water resources. The assessments are finalized with implications on the future of a major component of diving tourism in the north Aegean - the red coral.Yayın Assessment of projected changes in temperature and precipitation climatology over the CORDEX region 9 via multi model ensemble mean of CMIP5 models(European Geosciences Union (EGU), 2016-04-22) Turp, Mustafa Tufan; Öztürk, Tuğba; Kurnaz, Mehmet LeventIn this study, we conduct a multi-model ensemble mean approach in order to investigate of projected changesin fundamental climate variables (i.e. mean air temperature, minimum temperature, maximum temperature,and precipitation total) over the CORDEX-Australasia domain based on the outputs of various coupled globalclimate models (GCMs) participating in the World Climate Research Programme (WCRP) Coupled ModelIntercomparison Project (CMIP5). In this respect, in order to analyze projected future changes in temperature andprecipitation climatology, seasonal averages, and inter-annual variability over the Australasia (known as Region9) domain, where is one of fourteen domains of the Coordinated Regional Climate Downscaling Experiment (CORDEX), we focus on historical, RCP4.5 and RCP8.5 experiments of the GCMs for reference- (1981 - 2000),near- (2016 - 2035), mid- (2046 - 2065), and long-term (2081 - 2100), respectively.Yayın Future projections of air temperature and precipitation for the CORDEX-MENA domain by using RegCM4.3.5(European Geosciences Union (EGU), 2015-04-17) Öztürk, Tuğba; Turp, Mustafa Tufan; Türkeş, Murat; Kurnaz, Mehmet LeventIn this study, the projected changes for the periods of 2016 – 2035, 2046 – 2065, and 2081 – 2100 in the seasonal averages of air temperature and precipitation variables with respect to the reference period of 1981 - 2000 were examined for the Middle East and North Africa region. In this context, Regional Climate Model (RegCM4.3.5) of ICTP (International Centre for Theoretical Physics) was run by using two different global climate models. MPIESM-MR global climate model of the Max Planck Institute for Meteorology and HadGEM2 of the Met Office Hadley Centre were dynamically downscaled to 50 km for the CORDEX-MENA domain. The projections were realized according to the RCP4.5 and the RCP8.5 emission scenarios of the IPCC (Intergovernmental Panel of Climate Change).
