Indigenous children's multimodal communication of emotions through visual imagery

Billions of images are shared worldwide on the internet via social platforms like Instagram, Pinterest, Snapchat and Twitter every few days. The social web and mobile devices make it quicker and easier than ever before for young people to communicate emotions through digital images. There is a need for greater knowledge of how to educate children and young people formally in the sophisticated, multimodal language of emotions. This includes semiotic choices in visual composition, such as gaze, facial expression, posture, framing, actor-goal relations, camera angles, backgrounds, props, lighting, shadows and colour. In particular, enabling Indigenous students to interpret and communicate emotions in contemporary ways is vital because multimodal language skills are central to academic, behavioural and social outcomes. This paper reports original research of urban, Indigenous, upper primary students' visual imagery at school. A series of full-day, digital imagery workshops were conducted over several weeks with 56 students. The photography workshops formed part of a three-year participatory community research project with an Indigenous school in Southeast Queensland, Australia. The archived student images were organised and analysed to identify attitudinal meanings from the appraisal framework, tracing types and subtypes of affect, and their positive and negative forms. The research has significant implications for teaching students how to design high-quality, visual and digital images to evoke a wide range of positive and negative emotions, with particular considerations for Australian Indigenous students

Simulaciones atomísticas de la curvatura del ADN: implicaciones para su circularización, la unión de factores de transcripción y su modulación por fármacos antitumorales

La trabectedina (Yondelis®) es un potente agente antitumoral de origen marino obtenido por la compañía española PharmaMar. Esta molécula se une de forma covalente al surco menor del ADN e induce curvatura de la doble hélice hacia el surco mayor que ha sido estudiada tanto por métodos experimentales como teóricos. La primera indicación para la que fue aprobada trabectedina, debido a su inusitada eficacia, fue el liposarcoma mixoide (LSM), un tumor de tejidos blandos que aparece como consecuencia de la translocación cromosómica t(12;16)(q13;p11). Esta traslocación da lugar a un factor de transcripción anormal, FUS-CHOP o TLS-DDIT3, que se comporta como una oncoproteína, impidiendo la diferenciación normal de los adipocitos y produciendo una proliferación incontrolada de sus precursores celulares. Se han descrito hasta 12 tipos diferentes de transcritos FUS-CHOP y, curiosamente, se ha comprobado que el tipo de transcrito presente en el tumor es determinante a la hora de conseguir una respuesta favorable a trabectedina. Así, los pacientes que presentan las variantes I o II responden mejor al tratamiento mientras que los tumores que presentan el tipo III son menos susceptibles. Trabectedina detiene el crecimiento del LSM y actúa como un estimulante de la diferenciación adipocítica, ya que bloquea la transactivación llevada a cabo por la oncoproteína. Este hecho extraordinario se ha atribuido a la capacidad del fármaco de producir la separación de la quimera FUS-CHOP de sus promotores diana y retrasar la formación del mismo complejo con el tiempo. Ante estos hallazgos experimentales, y sobre la base de los antecedentes de modelado molecular del grupo de investigación, decidimos intentar dilucidar el mecanismo mediante el cual la trabectedina logra separar la quimera del ADN. Como sabemos que este fármaco produce curvatura del ADN hacia el surco mayor al unirse covalentemente en el surco menor, planteamos la hipótesis de que esta curvatura en regiones promotoras a las que se unen los transcritos FUS-CHOP es la responsable de impedir el reconocimiento del ADN por parte del dominio de unión a ADN de FUS-CHOP. Mediante técnicas de modelado y simulación molecular hemos estudiado: (i) la curvatura intrínseca de diferentes secuencias de ADN que dan lugar a círculos de doble cadena covalentemente cerrados en ensayos de ligado y circularización, a través del análisis de los parámetros helicoidales derivados de su secuencia, (ii) la curvatura inducida en el ADN tras la unión de los dos únicos fármacos descritos (trabectedina y calicheamicina) que se sabe aumentan la ratio de circularización de determinadas secuencias de ADN, mediante el análisis de los cambios en los parámetros helicoidales del ADN tras su unión a la doble hélice, (iii) el papel de la unión de la T4 ADN ligasa empleada en los ensayos de circularización en la curvatura del ADN. Con toda la información obtenida referente a la unión 9 de proteínas y fármacos al ADN y el impacto en su curvatura, hemos propuesto un modelo para explicar el mecanismo de acción de trabectedina en LSM.Trabectedin (Yondelis®) is a potent anti-tumour agent of marine origin developed by the Spanish company PharmaMar. This molecule covalently binds to the minor groove of DNA and induces bending of the double helix towards the major groove, a process that has been studied both experimentally and theoretically. The first indication trabectedin was approved for, due to its unprecedented efficacy, was myxoid liposarcoma (MLS), a soft tissue tumour resulting from chromosomal translocation t(12;16)(q13;p11). This translocation gives rise to an abnormal transcription factor, FUS-CHOP or TLS-DDIT3, which behaves like an oncoprotein, preventing normal differentiation of adipocytes and leading to uncontrolled proliferation of their cell precursors. Up to 12 different types of FUS-CHOP transcripts have been described. Interestingly, it has been found that the type of transcript present in the tumour is a determining factor when it comes to achieving a favourable response to trabectedin. Thus, patients with variants I or II respond better to treatment while tumours with type III are less susceptible. Trabectedin prevents the growth of MSL and acts as a stimulant of adipocyte differentiation by blocking the transactivation carried out by the oncoprotein. This remarkable fact has been attributed to the drug's ability to cause detachment of the FUS-CHOP chimera from its target promoters and delay the formation of the FUS-CHOP complex over time. Given these experimental findings, and based on the molecular modelling background of the research group, we decided to try to elucidate the mechanism by which trabectedin separates the chimera from the DNA. As we know that this drug causes DNA bending towards the major groove by covalently binding to the minor groove, we hypothesised that this curvature in promoter regions to which FUS-CHOP transcripts bind might be responsible for preventing DNA recognition by the DNA-binding domain of FUS-CHOP. By means of molecular modelling and simulation techniques we have studied: (i) the intrinsic curvature of different DNA sequences that give rise to covalently closed double-stranded circles in ligation and circularisation assays, through the analysis of the helical parameters derived from their sequence, (ii) the curvature induced in DNA upon binding of the only two drugs described (trabectedin and calicheamicin) that are known to increase the circularisation ratio of certain DNA sequences, by analysing the changes in DNA helical parameters after binding to the double helix, (iii) the role of the binding of the T4 DNA ligase used in circularisation assays on DNA curvature. Based on all the information obtained regarding protein and drug binding to DNA and the impact on its curvature, we have proposed a model to explain the mechanism of action of trabectedin in MLS

Built-in reliability design of a high-frequency SiC MOSFET power module

A high frequency SiC MOSFET-based three-phase, 2-level power module has been designed, simulated, assembled and tested. The design followed a built-in reliability approach, involving extensive finite-element simulation based analysis of the electro-thermo-mechanical strain and stress affecting the switch during both manufacturing and operation: structural simulations were carried out to identify the materials, geometry and sizes of constituent parts which would maximize reliability. Following hardware development, functional tests were carried out, showing that the module is suitable for high switching frequency operation without impairing efficiency, thus enabling a considerable reduction of system-level size and weight

Testing of a lightweight SiC power module for avionic applications

Functional and performance tests of a three-phase, two-level power module based on CREE 1.2kV SiC MOSFETs for avionic applications is presented in this paper. SiC devices have superior properties over conventional Si devices at high voltage operations and these properties make SiC devices at-tractive for avionic industry in order to reduce size of power electronic converters while maintaining high efficiency. This paper starts with a brief explanation of thermo-mechanical de¬sign approach of SiC power module. Thermo-mechanical de¬sign is followed by test setup and experimental results for dif¬ferent load and switching frequency conditions. The module is tested up to 540V DC link voltage, 6kW output power with 100kHz switching frequency. Experimental results show that the module can be successfully operated with high efficiency at high switching frequencies

Deeper, Wider, Sharper: Next-Generation Ground-Based Gravitational-Wave Observations of Binary Black Holes

Next-generation observations will revolutionize our understanding of binary black holes and will detect new sources, such as intermediate-mass black holes. Primary science goals include: Discover binary black holes throughout the observable Universe; Reveal the fundamental properties of black holes; Uncover the seeds of supermassive black holes.Comment: 14 pages, 3 figures, White Paper Submitted to Astro2020 (2020 Astronomy and Astrophysics Decadal Survey) by GWIC 3G Science Case Team (GWIC: Gravitational Wave International Committee

A physical RC network model for electro-thermal analysis of a multichip SiC power module

This paper is concerned with the thermal models which can physically reflect the heat-flow paths in a lightweight three-phase half bridge, two-level SiC power module with 6 MOSFETs and can be used for coupled electro-thermal simulation. The finite element (FE) model was first evaluated and calibrated to provide the raw data for establishing the physical RC network model. It was experimentally verified that the cooling condition of the module mounted on a water cooler can be satisfactorily described by assuming the water cooler as a heat exchange boundary in the FE model. The compact RC network consisting of 115 R and C parameters to predict the transient junction temperatures of the 6 MOSFETS was constructed, where cross-heating effects between the MOSFETs are represented with lateral thermal resistors. A three-step curve fitting method was especially developed to overcome the challenge for extracting the R and C values of the RC network from the selected FE simulation results. The established compact RC network model can physically be correlated with the structure and heat-flow paths in the power module, and was evaluated using the FE simulation results from the power module under realistic switching conditions. It was also integrated into the LTspice model to perform the coupled electro-thermal simulation to predict the power losses and junction temperatures of the 6 MOSFETs under switching frequencies from 5 kHz to 100 kHz which demonstrate the good electro-thermal performance of the designed power module

Identifying heavy stellar black holes at cosmological distances with next-generation gravitational-wave observatories

We investigate the detectability of single-event coalescing black hole binaries with total mass of 100–600 M at cosmological distances (5 z 20) with the next generation of terrestrial gravitational wave observatories, specifically Einstein Telescope and Cosmic Explorer. Our ability to observe these binaries is limited by the low-frequency performance of the detectors. Higher order multipoles of the gravitational wave signal are observable in these systems, and detection of such multipoles serves to both extend the mass range over which black hole binaries are observable and improve the recovery of their individual masses and redshift. For high-redshift systems of ∼ 200 M we will be able to confidently infer that the redshift is at least z = 12, and for systems of ∼ 400 M we can infer a minimum redshift of at least z = 8. We discuss the impact that these observations will have in narrowing uncertainties on the existence of the pair-instability mass gap, and their implications on the formation of the first stellar black holes that could be seeds for the growth of supermassive black holes powering high-z quasars

Identifying heavy stellar black holes at cosmological distances with next generation gravitational-wave observatories

We investigate the detectability of single-event coalescing black hole binaries with total mass of $100-600 M_{\odot}$ at cosmological distances ($5 \lesssim z \lesssim 20$) with the next generation of terrestrial gravitational wave observatories, specifically Einstein Telescope and Cosmic Explorer. Our ability to observe these binaries is limited by the low-frequency performance of the detectors. Higher-order Multipoles of the gravitational wave signal are observable in these systems, and detection of such multipoles serves to both b the mass range over which black hole binaries are observable and improve the recovery of their individual masses and redshift. For high redshift systems of $\sim 200 M_{\odot}$ we will be able to confidently infer that the redshift is at least $z=12$, and for systems of $\sim 400 M_{\odot}$ we can infer a minimum redshift of at least $z=8$. We discuss the impact that these observations will have in narrowing uncertainties on the existence of the pair-instability mass-gap, and their implications on the formation of the first stellar black holes that could be seeds for the growth of supermassive black holes powering high-$z$ quasars.Comment: 19 pages, 16 figure

Muon-spin relaxation investigation of magnetic bistability in a crystalline organic radical compound

We present the results of a muon-spin relaxation ($\mu^{+}$SR) investigation of the crystalline organic radical compound 4-(2-benzimidazolyl)-1,2,3,5-dithiadiazolyl (HbimDTDA), in which we demonstrate the hysteretic magnetic switching of the system that takes place at $T = 274 \pm 11\,\mathrm{K}$ caused by a structural phase transition. Muon-site analysis using electronic structure calculations suggests a range of candidate muon stopping sites. The sites are numerous and similar in energy but, significantly, differ between the two structural phases of the material. Despite the difference in the sites, the muon remains a faithful probe of the transition, revealing a dynamically-fluctuating magnetically disordered state in the low-temperature structural phase. In contrast, in the high temperature phase the relaxation is caused by static nuclear moments, with rapid electronic dynamics being motionally narrowed from the muon spectra

Plant-microbial linkages underpin carbon sequestration in contrasting mountain tundra vegetation types

Tundra ecosystems hold large stocks of soil organic matter (SOM), likely due to low temperatures limiting rates of microbial SOM decomposition more than those of SOM accumulation from plant primary productivity and microbial necromass inputs. Here we test the hypotheses that distinct tundra vegetation types and their carbon supply to characteristic rhizosphere microbes determine SOM cycling independent of temperature. In the subarctic Scandes, we used a three-way factorial design with paired heath and meadow vegetation at each of two elevations, and with each combination of vegetation type and elevation subjected during one growing season to either ambient light (i.e., ambient plant productivity), or 95% shading (i.e., reduced plant productivity). We assessed potential above-and belowground ecosystem linkages by uni-and multivariate analyses of variance, and structural equation modelling. We observed direct coupling between tundra vegetation type and microbial community composition and function, which underpinned the ecosystem's potential for SOM storage. Greater primary productivity at low elevation and ambient light supported higher microbial biomass and nitrogen immobilisation, with lower microbial mass-specific enzymatic activity and SOM humification. Congruently, larger SOM at lower elevation and in heath sustained fungal-dominated microbial communities, which were less substrate-limited, and invested less into enzymatic SOM mineralisation, owing to a greater carbon-use efficiency (CUE). Our results highlight the importance of tundra plant community characteristics (i.e., productivity and vegetation type), via their effects on soil microbial community size, structure and physiology, as essential drivers of SOM turnover. The here documented concerted patterns in above-and belowground ecosystem functioning is strongly supportive of using plant community characteristics as surrogates for assessing tundra carbon storage potential and its evolution under climate and vegetation changes