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    Archaeogenomic analysis of genetic and cultural interactions in Neolithic Anatolian societies (NEOGENE)

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    The Neolithic Transition in the Near East (c.10,000-6,000 BC) was a period of singular sociocultural change, when societies adopted sedentary life and agriculture for the first time in human history. This project will jointly use genomic and quantitative cultural data to explore Transition societies’ organisation, interactions, and their social and demographic evolution in time. (1) We will start by dissecting social structures within Neolithic communities in Anatolia, studying the role of kinship, postmarital residence customs, and endogamy. For this end, we will produce genotype data for c.250 individuals interred within five Pre-Pottery and Pottery Neolithic villages in South East and Central Anatolia, and analyse genomic relatedness patterns in the context of bioarchaeological similarity (e.g. by measuring genetic relatedness among Çatalhöyük individuals buried within the same house over generations). (2) We will study the means of cultural interaction among Near Eastern Neolithic societies by documenting which cultural traits -from skull removal customs to pottery- were most likely propagated through emulation and acculturation, and which ones by gene flow, when and where. Here we will produce whole genome data, compile genomic and material culture similarity matrices for >30 Near Eastern pre-Neolithic and Neolithic populations, and develop frameworks for integrated analysis of quantitative material culture and genomic similarity among populations (also including obsidian and sheep exchange connections as factors). The data will be analysed on multiple levels: within regions, interregional, and diachronic. (3) The work will conclude by examining the evolution of social organisation and population interaction patterns through the Neolithic Transition. While enriching and revising current Transition models, the project will set precedents for employing archaeogenomics to study social structures and for systematic co-analysis of genomic and archaeological data.H2020-EU.1.1. - EXCELLENT SCIENCE - European Research Council (ERC

    Timing and spectral analysis of 2S 1417-624 during its 2018 outburst

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    We investigate timing and spectral characteristics of the transient X-ray pulsar 2S 1417-624 during its 2018 outburst with NICER follow up observations. We describe the spectra with high-energy cut-off and partial covering fraction absorption (PCFA) model and present flux-dependent spectral changes of the source during the 2018 outburst. Utilizing the correlation-mode switching of the spectral model parameters, we confirm the previously reported sub-critical to critical regime transitions and we argue that secondary transition from the gas-dominated to the radiation pressure-dominated disc do not lead us to significant spectral changes below 12 keV. Using the existing accretion theories, we model the spin frequency evolution of 2S 1417-624 and investigate the noise processes of a transient X-ray pulsar for the first time using both polynomial and luminosity-dependent models for the spin frequency evolution. For the first model, the power density spectrum of the torque fluctuations indicate that the source exhibits red noise component (Gamma similar to -2) within the time-scales of outburst duration which is typical for disc-fed systems. On the other hand, the noise spectrum tends to be white on longer time-scales with high timing noise level that indicates an ongoing accretion process in between outburst episodes. For the second model, most of the red noise component is eliminated and the noise spectrum is found to be consistent with a white noise structure observed in wind-fed systems

    Carbon dioxide activated biochar-clay mineral composite efficiently removes ciprofloxacin from contaminated water - Reveals an incubation study

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    Ciprofloxacin, a second-generation synthetic fluoroquinolone derivative widely used in human and veterinary medicines, has the potential to pose a serious risk to aquatic organisms and humans. The current research investigated the removal of ciprofloxacin using biochar treated with clay mineral and subsequently activated with carbon dioxide (CO2) produced at two different pyrolysis temperatures (350 and 650 °C). Batch adsorption experiments were carried out to assess the removal efficiency of ciprofloxacin by as-synthesized materials. The effects of various factors, such as pH, contact time, adsorbent dose, initial ciprofloxacin concentration, and temperature were studied during the removal process. The physicochemical characterization results verified the successful loading of clay minerals on biochar. Non-linear adsorption models were employed to understand the nature of adsorption processes however, the Pseudo-second-order kinetic and Freudlich and Redlich Peterson isotherm models best fitted with the adsorption data. These findings indicated that the adsorption did not follow an ideal monolayer adsorption suggesting hybrid chemical adsorption process that was spontaneous and endothermic. The maximum adsorption (50.32 mg g−1) of ciprofloxacin was achieved by CO2 activated biochar-clay mineral composite prepared at 350 °C, and was almost two times higher than the pristine biochar at neutral pH and 40 °C. The possible proposed mechanisms involved for the removal of ciprofloxacin were electrostatic attraction, cation exchange, pore-filling effect, and π-π interactions. Our findings demonstrate that application of CO2 activated biochar-clay mineral composite is a promising technique for efficient removal of ciprofloxacin from aqueous solution

    Üreme Hakkı Politikalarının Türkiye'de Kadınların Yumurta ve Embriyo Dondurma Deneyimine Etkileri

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    Studies and analyses of reproduction policies are wrought with ambiguities in Turkey due to continuous changes within the legal framework. The aim of the study the effects of reproductive rights policies on women’s experience of egg and embryo freezing process in Turkey. In order to answer the research problem of the study, qualitative research is used as a tool. Semi- structured in depth interviews were conducted with 18 women who either freeze their eggs or freeze their embryos, regardless of women’s reasons for freezing. Thematic analysis employed as a method to research on women’s narratives and experiences. Thus, the snowball sampling technique and purposive sampling was used to determine participants for the study. ‘Dedoose’, a web based qualitative data analyzing program, is used for data management and analyzing purposes.Türkiye'de üreme politikalarına ilişkin çalışmalar ve analizler, yasal çerçevedeki sürekli değişimler nedeniyle belirsizliklerle işlenmektedir. Bu çalışmanın amacı, üreme hakkı politikalarının Türkiye'de kadınların yumurta ve embriyo dondurma deneyimine etkilerinin incelenmesidir. Araştırmanın problemine cevap verebilmek için araç olarak nitel araştırma kullanılmıştır. Kadınların dondurma nedenlerine bakılmaksızın yumurtalarını donduran veya embriyolarını donduran 18 kadınla yarı yapılandırılmış derinlemesine görüşmeler yapılmıştır. Kadınların anlatılarını ve deneyimlerini araştırmak için bir yöntem olarak kullanılan tematik analiz ile değerlendiriliştir. Bu nedenle araştırmanın katılımcılarını belirlemek için kartopu örnekleme tekniği ve amaçlı örnekleme kullanılmıştır. Web tabanlı nitel bir veri analiz programı olan 'Dedoose', veri yönetimi ve analizi amacıyla bu araştırmada kullanılmaktadır.M.S. - Master of Scienc

    Time-resolved microscopy of femtosecond laser filaments in fused quartz

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    Detailed picture of continuous shape evolution of femtosecond laser pulse has been recorded directly in the process of filament formation in fused silica using time-resolved polarization microscopy with similar to 70 fs temporal resolution. The main stages of the pulse transformation (temporal self-compression and splitting, formation of conical wave) have been studied. The maximum temporal compression has been found to be achieved by the leading subpulse after the time splitting event. It was found that the Bessel zone of conical wave formation is shifted backwards from the pulse front. Sub-and superluminal propagation velocities of the pulse maxima after the time splitting have been measured

    An investigation of functional quality characteristics and water interactions of navy bean, chickpea, pea, and lentil flours

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    Legume flours are great sources of protein, dietary fiber, starch, minerals, and vitamins. In recent years, the utilization of different legume flours in food systems has gained attention due to their sustainable and functional properties. This study aimed to characterize and examine the water interactions of different legume flours: navy bean, chickpea, pea, and lentil. For this purpose, in addition to the standard techniques (proximal analysis, Fourier transform infrared, protein solubility, and water solubility/absorption index), time-domain nuclear magnetic resonance (TD-NMR) relaxometry was also performed to explain the molecular interactions in the flours. Based on the results, carbohydrate and protein content of legume flours varied from 67.44 to 72.23 (g/100 g dw) and 23.19 to 27.03 (g/100 g dw) with low fat (0.86–5.44 [g/100 g dw]) and moisture content (6.01–8.14 [g/100 g dw]). Despite the slight differences in their compositions being small, moisture, protein, and carbohydrate contents influenced flour–water interactions. Thus, flour–water mixtures were assessed, and findings showed that water solubility index (WSI) followed the order: chickpea > lentil > navy bean > pea, whereas water absorption index (WAI) followed the order: pea > navy bean > lentil > chickpea. T2 relaxation times measured by NMR and protein solubility results were also in accordance with these results. The results of this study demonstrated that legume flours that were investigated offered potential for commercial applications. Because various food applications require different flour–water interactions, a suitable flour can be selected by considering these results

    Faster characteristic three polynomial multiplication and its application to NTRU Prime decapsulation

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    Efficient computation of polynomial multiplication over characteristic three fields is required for post-quantum cryptographic applications which gain importance upon the recent advances in quantum computers. In this paper, we propose three new polynomial multiplication algorithms over F-3 and show that they are more efficient than the current state-of-the-art algorithms. We first examine through the well-known multiplication algorithms in F-3[x] including the Karatsuba 2-way and 3-way split formulas along with the latest enhancements. Then, we propose a new 4-way split polynomial multiplication algorithm and an improved version of it which are both derived by using interpolation in F-9, the finite field with nine elements. Moreover, we propose a 5-way split multiplication algorithm and then compare the efficiencies of these algorithms altogether. Even though there exist 4-way or 5-way split multiplication algorithms in characteristic two (binary) fields, there has not been any such algorithms developed for characteristic three fields before this paper. We apply the proposed algorithms to the NTRU Prime protocol, a post-quantum key encapsulation mechanism, submitted to the MST PQC Competition by Bernstein et al., performing polynomial multiplication over characteristic three fields in its decapsulation phase. We observe that the new hybrid algorithms provide a 12.9% reduction in the arithmetic complexity. Furthermore, we implement these new hybrid methods on Intel (R) Core (TM) i7-9750H architecture using C and obtain a 37.3% reduction in the implementation cycle count

    Mentoring Practices in ELT Practicum: What Do the Leading Actors Experience?

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    The study aspired to explore the fulfilment of mentoring roles-responsibilities from the perspectives of student teachers, supervisors, and mentors. The participants consisted of 194 student teachers from English Language Teaching departments at three state universities, ten supervisors offering Practice Teaching course at these departments, and ten mentors with whom the supervisors and the student teachers cooperated at practice schools. Employing a mixed-methods design, the researchers collected quantitative data from student teachers through a questionnaire whereas supervisors and mentors were interviewed. The student teachers agreed on the fulfilment of their mentors' protector, facilitator-supporter, observer-feedback provider, and friend-colleague roles whereas they partially agreed on the fulfilment of trainer-informant, role model, assessor-evaluator, collaborator, and reflector roles. The qualitative findings of the study also underlined critical aspects regarding the planning and implementation phases of practicum, which is expected to guide teacher educators in mentoring practices. (C) Association of Applied Linguistics. All rights reserve

    Physical device simulation of dopant-free asymmetric silicon heterojunction solar cell featuring tungsten oxide as a hole-selective layer with ultrathin silicon oxide passivation layer

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    The dopant-related issues are amongst the major performance bottleneck in crystalline silicon solar cells that can be alleviated via implementation of dopant-free layers. This work presents the implementation of tungsten oxide (WOx) and titanium oxide (TiOx) as hole- and electron-selective films for heterostructure solar cell design whereby n-type Si wafer has been passivated with ultrathin silicon oxide (SiO2) layer. Several designs have been investigated including passivated hydrogenated amorphous silicon (i-a-Si:H) and characterized by evaluating work function, electron affinity, interfacial charge, and layer thickness. The high work function of WOx induces significant upward band bending to permit holes transportation towards anode, whereas, low electron-affinity for TiOx reduces the barrier against electrons at the cathode. Smaller band offsets have been observed against minority carriers for devices that employ passivated i-a-Si:H film. However, incorporating SiO2 significantly improves the energy barrier height against minority carriers that leads to an enhancement in electric field along with reduction in recombination. The best-performance device with an optimum SiO2 thickness of 1 nm numerically validated V-oc of 751 mV, J(sc) 40.2 mA/cm(2), FF 79.7%, and rl of 24.06%. A comparative analysis with hole-selective vanadium oxide (V2Ox) demonstrated eta of 21.73% limited by the low work function of V2Ox. (C) 2021 Elsevier Ltd. All rights reserved

    A virtual panopticon in Turkey during the COVID-19 pandemic: The case of location-based mobile application 'Hayat Eve Sığar'

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    Based on Jeremy Bentham's panopticon design (1785) as the architectural manifestation of surveillance, Foucault theorizes how modern societies are built upon the relationship between power and knowledge operated by surveillance, self-regulation, and participation. With the development of information and communication technologies, these power and surveillance mechanisms expand beyond the spatial boundaries. During the Covid-19 pandemic, the measures against the disease such as tracing, quarantine, and especially virtual surveillance to provide order and discipline for the public health with the citizens' compliance create panopticon-like organizations. With the locative media and surveillance, exemplified by the mobile application called 'Hayat Eve Sığar' (literally translated as 'life fits into home'), which is a part of the official precautionary measures against the Covid-19 disease in Turkey to trace and isolate the diseased, surveillance mechanisms become a binary system incorporating physical and virtual spaces. The 'Hayat Eve Sığar' application tracks the health statuses of the individuals and residences like the panopticon cells and shares the necessary information to protect the public. It transforms the perception and interpretation of space through the mediation of information and communication. In this regard, this study aims to investigate the intersections and ambiguity between information and surveillance, security and control, physical and virtual, urban places and electronic spaces, the public, and private spheres.information and surveillance, security and control, physical and virtual, urban places and electronic spaces, the public, and private spheres


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