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Teachers are working in disturbing and challenging times, characterised by coterminous crises, the Covid-19 pandemic and human induced climate change; these are transforming our working conditions and the lives of students and teachers. In this research, we looked to our own pedagogical practices as teacher educators to collaboratively explore what it means to be teachers and learners in uncertain times of multiple crises. We use a collaborative autoethnographic methodology to better understand the kind of educator these times demand and consider the implications for teacher education. Through fictionalised, co-constructed vignettes that act as pedagogical encounters, we explore our collaborative experiences in relation to multiple crises: in the classroom, at climate strikes, and in conversations with teachers during the pandemic. We use these vignettes to think with and through teaching during the global pandemic and the climate catastrophe, and with young people's climate activism. Thinking with these vignettes, we analyse the ways (young) people across the world were already creating and are continuing to create, prefiguratively, different possible futures through public and 'everyday' modes of political action for climate justice, and what this might mean for teacher education. [ABSTRACT FROM AUTHOR]

In this article, I examine how scientific boundary work describes or represents citizen science as credible forms of expertise. Citizen science is an ambiguous concept, and I leverage that ambiguity to examine citizen science as a proxy for nonprofessional or noninstitutional scientific practices more generally. I argue that media representations of citizen science perform boundary work through different articulations of institutional "buy-in" to the legitimacy or credibility of citizen science. Using a discourse analysis of mainstream news media, I trace three framings of citizen science's relationship to institutional networks, which I describe as subservient to, corrective to, and exceeding the norms of institutional expertise. I find that the perspectives of professional, credentialed scientists dominate public discourse concerning citizen science and perform different adjudications of how citizen science contributes to networks of expertise. By focusing on citizen science concerning human health and medicine, I additionally show how mainstream framings of citizen science engage with overlapping media representations of personal health responsibility and patient empowerment. I suggest that representations of citizen science as a form of "missing expertise" can conflict with portrayals of citizen science as "going too far" in the pursuit of treatments or interventions. [ABSTRACT FROM AUTHOR]

Chemically synthesized high-anisotropy magnetic nanoparticles have demonstrated thermal stability and extremely narrow size distributions that are critical for reducing noise in future media applications. Due to their monodispersity, they also exhibit emergent self-patterning that could potentially support bit-per-particle densities up to 2 to 8 Tb/[cm.sup.2] (10 to 50 Tb/ [in.sup.2]). The authors report on the challenges and progress in developing self-organized nanoparticle arrays for magnetic recording at densities up to and beyond 30 Gb/[cm.sup.2] (200 Gb/[in.sup.2]), and in particular describe the beneficial use of biological templates in developing such media. CoPt grains are prepared within monodisperse protein spheres from aqueous reactants, with synthesis conditions controlling grain size, structure, and composition. Dispersions of these protein-encapsulated grains can be induced to form patterned precursor films that retain long range order irrespective of a distribution in grain size. Assemblies are annealed to form films of L[1.sub.0] phase nanomagnets within carbonized shells that can support stable transitions up to 1 Gb/[cm.sup.2] (6 Gb/[in.sup.2]). Index Terms--Magnetic films, magnetic liquids, magnetic recording, nanotechnology.

Hafnium oxide films were deposited with a range of substrate temperatures using a filtered cathodic vacuum arc deposition system. The microstructure, electronic structure, and electrical breakdown of the films were characterized. In films deposited at temperatures above 200 °C, the microstructure became more ordered and x-ray diffraction indicated that the dominant phase was monoclinic hafnium oxide. Evidence for the presence of the tetragonal phase was also found in the films deposited at temperatures above 400 °C. The near edge structure of the oxygen K-edge measured using x-ray absorption spectroscopy, provided further evidence that films prepared at high temperatures contained a combination of the monoclinic and tetragonal phases. Films deposited at room temperature were disordered and exhibited the best electrical breakdown characteristics. The electrical breakdown of the films deteriorated as the crystallinity increased with increasing deposition temperature. These results support the proposition that electrical breakdown paths may occur along grain boundaries in polycrystalline hafnium oxide films and therefore a disordered microstructure is preferable. [ABSTRACT FROM AUTHOR]

Ultraviolet (UV) Schottky detector devices were fabricated on polycrystalline wurtzite Zn1-xMgxO films energetically deposited onto a-plane sapphire at room-temperature (RT) and 200 °C. The unintentionally doped, transparent, n-Zn1-xMgxO films exhibit low surface roughness (<5% of film thickness), moderate carrier concentration, and Hall mobility up to 15 cm2 V-1 s-1. The direct bandgaps of the RT and 200 °C films (x = 0.24 and x = 0.20) were 3.57 eV and 3.40 eV. Schottky diodes with graphitic anodes formed on these films exhibited barrier heights up to 0.88 eV and ideality factors as low as 1.97. Spectral response measurements demonstrated UV/visible photo-current ratios up to ∼104. [ABSTRACT FROM AUTHOR]

We report on the properties of metal-semiconductor-field-effect-transistors (MESFETs) on ZnO films grown using the filtered cathodic vacuum arc (FCVA) technique. FCVA ZnO films deposited on a-plane sapphire at 200 °C showed good structural and electrical properties that improved further on annealing at 800 °C in oxygen, due to the formation of larger grains with lower inter-grain transport barriers. MESFETs with silver oxide and iridium oxide Schottky gates on these annealed films showed excellent long-term stability with low ideality factors (<1.3), low gate leakage, and channel mobilities up to 50 cm2/Vs that were unchanged with both age and stress testing. [ABSTRACT FROM AUTHOR]

Presents a study which examined the microstructure and magnetic properties of macroscopic magnetic bacterial threads. Fabrication of bacterial threads; Experimental results; Conclusions.

This paper presents a comprehensive experimental and theoretical investigation into the antiviral properties of nanostructured surfaces and explains the underlying virucidal mechanism. We used reactive ion etching to fabricate silicon (Si) surfaces featuring an array of sharp nanospikes with an approximate tip diameter of 2 nm and a height of 290 nm. The nanospike surfaces exhibited a 1.5 log reduction in infectivity of human parainfluenza virus type 3 (hPIV-3) after 6 h, a substantially enhanced efficiency, compared to that of smooth Si. Theoretical modeling of the virus-nanospike interactions determined the virucidal action of the nanostructured substrata to be associated with the ability of the sharp nanofeatures to effectively penetrate the viral envelope, resulting in the loss of viral infectivity. Our research highlights the significance of the potential application of nanostructured surfaces in combating the spread of viruses and bacteria. Notably, our study provides valuable insights into the design and optimization of antiviral surfaces with a particular emphasis on the crucial role played by sharp nanofeatures in maximizing their effectiveness.