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High-power pulsed electrochemiluminescence for optogenetic manipulation of <i>Drosophila</i> larval behaviour
No full textElectrochemiluminescence (ECL) produces light through electrochemical reactions and has shown promise for various analytic applications in biomedicine. However, the use of ECL devices (ECLDs) as light sources has been limited due to insufficient light output and low operational stability. In this study, we present a high-power pulsed operation strategy for ECLDs to address these limitations and demonstrate their effectiveness in optogenetic manipulation. By applying a biphasic voltage sequence with short opposing phases, we achieve intense and efficient ECL through an exciplex-formation reaction pathway. This approach results in an exceptionally high optical power density, exceeding 100 μW mm−2, for several thousand pulses. Balancing the ion concentration by optimizing the voltage waveform further improves device stability. By incorporating multiple optimized pulses into a pulse train separated by short rest periods, extended light pulses of high brightness and with minimal power loss over time were obtained. These strategies were leveraged to elicit a robust optogenetic response in fruit fly (Drosophila melanogaster) larvae expressing the optogenetic effector CsChrimson. The semi-transparent nature of ECLDs facilitates simultaneous imaging of larval behaviour from underneath, through the device. These findings highlight the potential of ECLDs as versatile optical tools in biomedical and neurophotonics research
Iron doped magnesium chromite spinel and LSM coating to diminish chromium poisoning in the SOFC cathode environment
No full textSolid oxide fuel cells (SOFCs) suffer from degradation issues primarily arising from their high operating temperatures. Among the most critical degradation mechanisms is cathode poisoning by volatile chromium species from Fe–Cr-based metallic interconnects. A widely adopted strategy to mitigate this problem involves applying protective surface coatings to the interconnects. In this study, protective layers were deposited on AISI 430 stainless steel using the screen-printing method. A bilayer coating comprising a chromium-rich spinel (MgFe0.1Cr1.9O4) and a perovskite (La0.65Sr0.35)0.95MnO3 (LSM) was applied to enhance oxidation resistance and minimise the increase in electrical resistance. Three types of substrates, bare, single-layer LSM-coated, and bilayer (spinel-perovskite) coated, were subjected to 1000-h oxidation at 800 °C in static air, simulating SOFC cathode operating conditions without electrical load. The bilayer-coated steel exhibited excellent long-term durability, with no detectable chromium migration from the steel or spinel layer to the LSM surface. The chromite spinel layer significantly improved LSM adhesion, prevented cracking and buckling, and maintained a stable oxide layer thickness (∼3 μm) at the coating-substrate interface. The area-specific resistance (ASR) of the bilayer-coated steel remained low, measured at 0.056 Ω cm2 after 1000 h, outperforming both the uncoated and LSM monolayer coated samples
Folk music
No full textWhen Cohen started to write songs, the musical formation of which he was first a part was the folk scene. Cohen reports that socialist folk singers in Montreal first got him interested in songs. When he decided to pursue a career as a singer and songwriter, he went to New York, because it was the hub of North American folk music. He hung out and performed at such folk venues as the Bitter End, and his songs were first recorded by such folk singers as Judy Collins. Cohen’s earliest songs display the influence of this scene, as did his preferred style of performance, accompanying himself on an acoustic guitar. His unhappiness with the way some of the songs on his first album were produced seems to have stemmed from their not sounding like folk. And yet the lyrics of Cohen’s songs have little in common with those typical of a genre that claimed to reflect the people rather than the individual. This chapter considers how folk molded Cohen’s work, and where his work pushed the boundaries of the genre
Doctoral journeys-beyond the Doctorate:Sin-Wang Chong (Part 1)
No full textThis article presents insights from an interview with Sin-Wang Chong, focusing on his doctoral journey and the formative experiences that shaped his development as a researcher, drawing on materials reported in Imanishi (2025a, 2025b; 2025c). By tracing his pathway, including early teaching experiences, his transition into educational research, and the challenges of completing a PhD by publication, the article offers reflections relevant to practitioner-researchers and doctoral students. A follow-up article (Part 2) will examine his professional journey in greater depth
Black Holes and Prisoners: Understanding AS112 Deployment Characteristics
No full textAS112 is a distributed, volunteer-run, anycast DNS service that acts as a sink for leaked DNS queries for local resources, preventing them from overloading core DNS infrastructure. AS112 helps protect important parts of the Internet infrastructure, but there has been no comprehensive study of who runs the AS112 servers, where they are located, and whether they effectively capture leaked queries. Using RIPE Atlas and 33646 open recursive resolvers, we detect 469 AS112 sites, run by 97 operators, and compare the response time and query distances of AS112 to root server queries. AS112 performs well, with 23.21% lower median response times and 36.11% lower median distances than the root. However, AS112 is dependent on a small number of large operators (one operator serves 41.71% of probes in our study), limiting its resilience
Methods for analysing wildlife DNA methylation data
No full textThe analysis of DNA methylation data for wildlife conservation is gaining momentum as the technology for quantifying the methylome becomes mainstream. The use of epigenetic information extracted from tissue samples can be used for estimating chronological age, individual traits and phenotypic variation. Methylation data present an exciting opportunity to study wildlife populations, with the potential to provide insights into age structure, vital rates and health. However, the statistical methodology for answering the emerging research questions has been developed and mostly applied in the human biomedical setting. We review the key methodologies commonly used in wildlife settings, and methods that have been used only in human studies so far that could improve our understanding of wildlife epigenomic changes. We show how the different methods relate to each other and how they link to research questions, illustrating each approach with data from a case study, a large dataset from wild bottlenose dolphins (Tursiops spp.) from the US southeast and Gulf coast. Estimating chronological age from models called epigenetic clocks and understanding the relationship between epigenetic indicators of health and exposure to stressors are both key goals in wildlife settings; however, we show that a single model cannot do both accurately. This is a fundamental limitation of clock-type models and might explain why some age-related health conditions have been found to be related to epigenetic age and others not. Decoupling the analysis of age and health is challenging because the two are confounded but is especially important in wildlife settings where age prediction is often the main analytical objective
Conjugacy for certain automorphisms of the one-sided shift via transducers
No full textWe address the following open problem, implicit in the 1990 article Automorphisms of one-sided subshifts of finite type of Boyle, Franks and Kitchens (BFK):Does there exist an element ψ in the group of automorphisms of the one-sided shift Aut({0, 1, . . . , n − 1}ℕ, σn) so that all points of {0, 1, . . . , n − 1}ℕ have orbits of length n under ψ and ψ is not conjugate to a permutation?Here, by a permutation we mean an automorphism of the one-sided shift dynamical system induced by a permutation of the symbol set {0, 1, . . . , n − 1}.We resolve this question by showing constructively that any ψ with properties as above must be conjugate to a permutation.Our techniques naturally extend those of BFK using the strongly synchronizing automata technology developed here and in several articles of the authors and collaborators (although this article has been written to be largely self-contained)
Giovanni Dario's scripted legacies:textual self-presentation in Renaissance Venice
No full textGrowing critical interest in the Cretan-Venetian ducal secretary, polyglot diplomat, confraternity warden and palace builder Giovanni Dario has thrown important light on his biography and career, especially on his outstanding diplomatic work in successive spells brokering peace between Venice and the courts of Mehmet II and Beyazid II. The best known of his surviving writings, his 22 diplomatic letters (1484-1485) from Ottoman Turkey, are referred to, and occasionally excavated, by historians of Venice and the Levant. Dario’s texts are striking for their high degree of self awareness, with consistent foregrounding of a curated image which has no parallel among Venetian public servants of the Quattrocento. They have never been considered together in this performative light, and the precise nature of the language and lettering they deploy has been overlooked. The present essay is the first attempt at rectifying this situation. My guiding contention is that Dario’s letters, wills and lapidary inscription were crafted, in both message and medium, to project a carefully controlled legacy persona to their respective audiences: the political elite of the Serenissima; executors and beneficiaries; Venice and posterity. All evidence for this from Dario’s written inheritance has been transcribed anew in the study. Particular scrutiny is reserved for three representative primary sources: the dispatch of December 6th 1484 from Adrianople, the will of 1492 and the Ca’ Dario epigraph from the late 1480s. These are offered in philological first editions, with translations, illustrations and contextual analysis
The Old Problem Problem
No full textConceptual Engineering promises to deliver a new (or unduly neglected) way of doing philosophy whereby progress is to be made by assessing and improving our representational devices (words, concepts, meanings). This methodology faces a famous objection. Namely, Strawson’s Objection: ‘To do [Conceptual Engineering] is not to solve the typical philosophical problem, but to change the subject’ (Strawson [1963]. “Carnap’s Views on Conceptual Systems versus Natural Languages in Analytic Philosophy.” In The Philosophy of Rudolf Carnap, edited by Paul Arthur Schilpp, 503–518. La Salle: Open Court). Despite being over sixty years old, this Objection has yet to receive a fully satisfactory treatment – or so it will be argued. In fact, there are really two worries at large here. There is Strawson’s original worry plus a strengthened, deeper problem: even if you are not changing the subject in doing Conceptual Engineering, you are still not solving the original problem. This deeper objection is The Old Problem Problem. The primary goal here is to offer a response to this Problem which, in turn, delivers a new solution to Strawson’s Objection. This then yields a response to a related worry (The New Problem Problem): Conceptual Engineers are just answering questions that weren’t being asked. The aim here is not to defend Conceptual Engineering as such but to gain a better (more pluralist) picture of what this new approach to philosophy does, and does not, involve.<br/
Cross-domain neural alignment (CDNA):a deep supervised domain adaptation in human activity recognition using device-free sensing
No full textWi-Fi sensor networks have grown rapidly due to their scalability and high data throughput, finding applications in tasks like tracking human motion in laboratory settings. These systems detect motion by analyzing fluctuations in radio signals caused by target movements, which generate identifiable activity patterns. However, their performance is influenced by factors such as environmental changes, unseen target subjects, multi-target tracking, data configurations, and the nature of target activities. These challenges lead to domain shifts between the training and testing phases, a common issue in real-world scenarios known as the domain-shifting problem in transfer learning. We propose a supervised domain alignment technique to address domain shifts in Wi-Fi sensor Channel State Information (CSI) datasets using minimal labeled target data. Our method outperforms state-of-the-art adversarial models trained on similar data, achieving superior cross-domain prediction accuracy. Evaluations on two public CSI datasets show consistent improvements, with an average Micro-F1 score of 90% for cross-user tasks and 67% for cross-user and cross-environment tasks using only 70 labeled target samples. This approach demonstrates its effectiveness in enhancing prediction accuracy under challenging domain shift scenarios
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