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A Critical Reflection on Sonic Maps and the Search for an Audiovisual Cartography Model
No full textSound is a spatiotemporal formation and the soundscape is a context-dependent perceptual phenomenon for the interrelationship between sound and space. Conventional maps tend towards a cartographic silence regarding their sonic spatiotemporality. Although critical cartography investigates different aspects of space, its relation to soundmapping is debatable. The growing interest in audiovisual cartography, however, has led to various approaches to associating sound and image in different fields such as cinema, soundscapes, human geography, and urbanism. This paper focuses on soundscape mapping and critically reflects on the limitations of existing strategies. Its main objective is to present an audiovisual cartography framework to promote broader conceptualizations and comprehensive applications of soundscape mapping. This paper defines the unique characteristics of sound phenomena that ground sonic ways of thinking in an audiovisual mapping model, and concludes with a critique of critical cartography to interrogate why it fails to meet the new insights arising from audiovisual integration
The NANOGrav 15 yr Data Set: Running of the Spectral Index
No full textThe NANOGrav 15 yr data provide compelling evidence for a stochastic gravitational-wave (GW) background at nanohertz frequencies. The simplest model-independent approach to characterizing the frequency spectrum of this signal consists of a simple power-law fit involving two parameters: an amplitude A and a spectral index γ. In this Letter, we consider the next logical step beyond this minimal spectral model, allowing for a running (i.e., logarithmic frequency dependence) of the spectral index, grun (f ) = g + b ln (f /fref ). We fit this running-power-law (RPL) model to the NANOGrav 15 yr data and perform a Bayesian model comparison with the minimal constant-power-law (CPL) model, which results in a 95% credible interval for the parameter β consistent with no running, b Î [-0.80, 2.96], and an inconclusive Bayes factor, B(RPL versus CPL) = 0.69 ± 0.01. We thus conclude that, at present, the minimal CPL model still suffices to adequately describe the NANOGrav signal; however, future data sets may well lead to a measurement of nonzero β. Finally, we interpret the RPL model as a description of primordial GWs generated during cosmic inflation, which allows us to combine our results with upper limits from Big Bang nucleosynthesis, the cosmic microwave background, and LIGO–Virgo–KAGRA
Pre-processing of paleogenomes: mitigating reference bias and postmortem damage in ancient genome data
No full textWe investigate alternative strategies against reference bias and postmortem damage in low coverage paleogenomes. Compared to alignment to the linear reference genome, we show that masking known polymorphic sites and graph alignment effectively remove reference bias, but only starting from raw read files. We next study approaches to overcome postmortem damage: trimming, rescaling, and our newly developed algorithm, bamRefine (github.com/etkayapar/bamRefine and zenodo.org/records/14234666), masking reads only at positions possibly affected by PMD. We propose graph alignment coupled with bamRefine as a simple strategy to minimize data loss and bias, and urge the community to publish FASTQ files
Analysis of Three Complement-Taking Predicates in Spoken Turkish: bil, san, and zannet
No full textThis paper presents a corpus-based synchronic investigation of three Turkish mental–cognitive verbs in the present tense: san ‘guess, believe’ and zannet ‘suppose, assume’ (in the first person) and bil ‘know’ (in the second person), in spoken discourse. These verbs, known as complement-taking predicates (CTPs), tend to appear without clausal complements in discourse and function as idiomatic units conveying epistemic modality. This paper characterizes the distribution of occurrences of the three predicates based on frequency to determine the extent to which usage frequency has led to routinization and greater autonomy for the CTPs under investigation, showing that the clause-medial variants deserve attention, as they clearly demonstrate the parenthetical behavior, autonomy, capacity to fulfill pragmatic functions, and projective force of foreshadowing new information of the predicates
From the ambivalent to the material: personification, spatialization and ritualization of liberty in the late Ottoman period (1908–1913)
No full textA systematic review of green and sustainable chemistry training research with pedagogical content knowledge framework: current trends and future directions
No full textThis study reviewed the green and sustainable chemistry education (GSCE) research that provided training at the tertiary level from 2000 to 2024. The Web of Science and ERIC databases were screened using title and abstract review. In total, 49 studies were analysed. The analysis instrument has two main parts, namely, general characteristics of the training, which was formed in light of the GSCE literature (i.e., chemistry sub-disciplines, type of implementation, and context), and analysis of the training through the lens of pedagogical content knowledge (PCK) construct that is the commonly-used framework for the analysis of training regarding orientation to teaching GSCE, learner, curriculum, assessment, and instructional strategies utilised. Results showed that organic chemistry (n = 15) is the most emphasised branch of chemistry in the articles. Regarding the learner component, the studies were inadequate, and very few studies provided information about the misconceptions and difficulties that students may encounter while learning GSC. Regarding the curriculum component, among the green chemistry principles, 'use of renewable feedstocks' was the most emphasised, while the least emphasised ones were 'reduce derivatives' and 'real-time pollution prevention'. Fourteen studies used subject-specific teaching strategies (e.g., cooperative teaching and project-based strategies). Although representations are not used in GSCE, most of the studies included laboratory studies (n = 31). Finally, regarding the assessment, very few studies focused on measuring students' skills (laboratory skills, discussion skills, etc.) and affective variables. In light of the findings, GSCE training should get more benefit from the literature on science/chemistry teaching strategies. Moreover, alternative assessment tools (e.g., rubrics and concept maps) should be utilized regarding the instruments utilized to assess the participants' GSC knowledge
Proposal of dual-gate oxide layered with HfO2: Comparative results with SiO2-RadFET
No full textThe aim of this study is to develop pMOS dosimeters that can exhibit high performance at high radiation doses compared to traditional SiO2-based RadFETs, for which a dual-gate oxide-layered sensor is proposed. The sensor chips, consisting of two RadFETs of identical thickness and geometry, were fabricated with sensitive region materials of 100 nm and 300 nm thick SiO2, as well as 40 nm HfO2/5 nm SiO2. The threshold voltages (Vth) of the sensors were determined based on voltage values corresponding to 10 μA ve 50 μA currents. The initial Vth values at 10 μA/50 μA of the RadFETs were −2.89 ± 0.01 V/−3.84 ± 0.01 V for 100 nm SiO2, -4.37 ± 0.02 V/-6.02 ± 0.02 for 300 nm SiO2, and -1.04±<%0.08 V/-1.507 ± 0.002 V for HfO2/SiO2. RadFETs were irradiated under a60Co radioactive source within a dose range of 1–20 Gy. The sensitivities of the sensors for a cumulative dose of 20 Gy were calculated as 9.19 ± 0.21/9.81 ± 0.19 mV/Gy for 100 nm-SiO2-RadFET, 43.72 ± 0.80/45.94 ± 0.68 mV/Gy for 100 nm-SiO2-RadFET, and 0.83 ± 0.01/0.87 ± 0.02 mV/Gy for DGHK-RadFETs (dual-gate oxide layered with high-k), based on data obtained at 10/50 μA, respectively. No degradation was observed in any of the sensors during the studied dose range, and the DGHK-RadFETs demonstrated particularly stable behavior. Lower error rates in performance parameters, higher stability, more durable in high radiation environments, greater dose storage capability with the lowest fading values, and the ability to reach saturation at higher doses were observed in DGHK-RadFETs compared to SiO2-RadFETs. All these superior properties compared to traditional structures have been achieved in DGHK-RadFETs with a thinner sensitive region. The DGHK-RadFET prototype is a promising candidate for potential applications in nuclear power plants, space research, high-energy physics laboratories, and defense and security applications
A Heterodox Approach for Designing Iron Photosensitizers: Pentacyanoferrate(II) Complexes with Monodentate Bipyridinium/Pyrazinium-Based Acceptor Ligands
No full textThe main obstacle in replacing well-established precious ruthenium photosensitizers with earth-abundant iron analogs is the short excited state lifetimes of metal-to-ligand charge transfer (MLCT) states due to relatively weak octahedral field splitting and relaxation via metal-centered (MC) states. In this study, we address the issue of short lifetime by using pentacyanoferrate(II) complexes and combat facile photodissociation by utilizing positively charged pyrazinium or bipyridinium ligands. We utilize femtosecond transient absorption spectroscopy alongside quantum chemical calculations to probe the excited states of three 4,4 '-bipyridinium- or pyrazinium-based pentacyanoferrate(II) complexes. The 4,4 '-bipyridinium-based complexes exhibit 3MLCT lifetimes of about 20 ps, while the pyrazinium-based complex exhibits a lifetime of 61 ps in an aqueous solution, setting a benchmark for cyanoferrate complexes. These results mark the foundation for a new group of easy-to-prepare iron photosensitizers that can be used for harvesting visible light
Thermochemical processing of organic wastes for sustainable valorisation and energy recovery: A review of recent contributions to the field
No full textThis paper reviews the current knowledge on the thermochemical processing of organic waste for sustainable valorisation and presents its impacts on energy recovery. We focused on novel, low-cost, and highly efficient thermochemical methods for converting organic waste into energy. Thermochemical processes for waste management are reported as sustainable alternatives for energy recovery, while generating other by-products for various applications. Thermochemical methods include hydrothermal processes, pyrolysis, and gasification. Additionally, torrefaction has been extensively studied in recent years for the pre-treatment of feedstock. Combustion and incineration are not discussed in this review, as conversion of carbon-rich feedstock into energy and valuable chemicals through gasification has several advantages over them. Recent contributions in this field have focused on enhancing the specificity of thermochemical processes for the sustainable valorisation of organic waste into high-value products. Waste valorisation fulfils the concept of biorefineries and the use of renewable energy, which helps attain the Sustainable Development Goals. Since thermochemical processing offers excellent opportunities to transform waste into valuable resources, this review paper will also highlight these crucial aspects within the concept of circular bioeconomy