Platform For Exploration Research Articles

Controlled Synthesis of Sub-Millimeter Nonlayered WO2 Nanoplates via a WSe2 -Assisted Method.

2Dmetal oxides (2DMOs) have stimulated tremendous attention due to their distinct electronic structures and abundant surface chemistry. However, it remains a standing challenge for the synthesis of 2DMOs because of their intrinsic 3Dlattice structure and ultrahigh synthesis temperature. Here, a reliable WSe2 -assisted chemical vapor deposition (CVD) strategy to grow nonlayered WO2 nanoplates with tunable thickness and lateral dimension is reported. Optical microscopy and scanning electron microscopy studies demonstrate that theWO2 nanoplates exhibit a well-faceted rhombic geometry with a lateral dimension up to the sub-millimeter level (≈135µm), which is the largest size of 2DMO single crystals obtained by CVD to date. Scanning transmission electron microscopy studies reveal that the nanoplates are high-quality single crystals. Electrical measurements show the nanoplates exhibit metallic behavior with strong anisotropic resistance, outstanding conductivity of 1.1×106 Sm-1 , and breakdown current density of 7.1×107 Acm-2 . More interestingly, low-temperature magnetotransport studies demonstrate that the nanoplates show a quantum-interference-induced weak-localization effect. The developed WSe2 -assisted strategy for the growth of WO2 nanoplates can enrich the library of 2DMO materials and provide a material platform for other property explorations based on 2D WO2 .

A hybrid polynomial-based optimization method for underwater gliders with parameter uncertainty

As a type of enduring platform for ocean exploration, underwater glider usually contains some uncertain parameters in actual engineering applications, which are related to manufacturing errors, assembly errors, and sensor measurement errors. Uncertain parameters will make the glider performance show uncertain characteristics, so it is necessary to consider their effects in the design optimization process for an underwater glider. In this paper, a hybrid polynomial-based optimization method is proposed to solve optimization problems of underwater gliders with parameter uncertainty. The hybrid polynomial consists of power function terms and trigonometric function terms, and it is used for fitting surrogate models of the glider dynamic models. The fitted surrogate models are used for quickly calculating the performance evaluation parameters of underwater gliders. Specifically, power function terms and trigonometric function terms correspond to optimization design variables and uncertain parameters, respectively. The hybrid polynomial method covers the convenience of the traditional response surface method and the advantage of the Chebyshev polynomial in interval analysis. Based on surrogate models and interval analysis, we can estimate boundary functions of performance evaluation parameters, and they are employed to construct optimization objective functions. Then, the optimization iteration calculation can be carried out. Here, the proposed method is used for determining the optimal control parameter values of the Petrel-II glider with the uncertainty of some configuration and measurement parameters. The optimization objectives are to minimize the specific energy consumption and maximize the average advance velocity simultaneously. Finally, some laws of the glider performance are summarized.

Activation of an actin signaling pathway in pre-malignant mammary epithelial cells by P-cadherin is essential for transformation.

Alterations in the expression or function of cell adhesion molecules have been implicated in all steps of tumor progression. Among those, P-cadherin is highly enriched in basal-like breast carcinomas, playing a central role in cancer cell self-renewal, collective cell migration and invasion. To establish a clinically relevant platform for functional exploration of P-cadherin effectors in vivo, we generated a humanized P-cadherin Drosophila model. We report that actin nucleators, Mrtf and Srf, are main P-cadherin effectors in fly. We validated these findings in a human mammary epithelial cell line with conditional activation of the SRC oncogene. We show that, prior to promoting malignant phenotypes, SRC induces a transient increase in P-cadherin expression, which correlates with MRTF-A accumulation, its nuclear translocation and the upregulation of SRF target genes. Moreover, knocking down P-cadherin, or preventing F-actin polymerization, impairs SRF transcriptional activity. Furthermore, blocking MRTF-A nuclear translocation hampers proliferation, self-renewal and invasion. Thus, in addition to sustaining malignant phenotypes, P-cadherin can also play a major role in the early stages of breast carcinogenesis by promoting a transient boost of MRTF-A-SRF signaling through actin regulation.

Pendant Length-Dependent Electrochemical Performances for Conjugated Organic Polymers as Solid-State Polymer Electrolytes in Lithium Metal Batteries.

The development of solid-state polymer electrolytes (SPEs) has been plagued by poor ionic conductivity, low ionic transference number, and limited electrochemical potential window. The exploitation of ionized SPEs is a feasible avenue to solve this problem. Herein, conjugated organic polymers (COPs) with excellent designability and rich pore structures have been selected as platforms for exploration. Three cationic COPs with different chain lengths of quaternary ammonium salts (CbzT@Cx, x = 4, 6, 9) are designed and applied to SPEs for the first time. Meanwhile, the effects of chain lengths on their electrochemical performances are compared. Especially, CbzT@C9 shows the most attractive electrochemical performance due to its high specific surface area of 212.3 m2 g-1. The larger specific surface area allows more exposure of the long-chain quaternary ammonium cation groups, which is more favorable for the dissociation of lithium salts. Moreover, the flexible long-chain structure increases the compatibility with poly(ethylene oxide) (PEO) and reduces the crystallinity of PEO to some extent. The richer pore structure can accommodate more PEO, further disrupting the crystallinity of PEO and creating more channels for the ether-oxygen chain to transport lithium ions. At 60 °C, the SPE (CbzTM@C9) presents an excellent ionic conductivity (σ) of 8.00 × 10-4 S cm-1. CbzTM@C9 has a lithium-ion transference number (tLi+) of 0.48. Thus, the assembled Li/CbzTM@C9/LiFePO4 battery provides a good discharge capacity of 158.8 mAh g-1 at 0.1C. After 70 cycles, the capacity retention rate is 93.8% with a Coulombic efficiency of 98%. The excellent flexibility brings stable power supply capability under various bending angles to the assembled Li/CbzTM@C9/LiFePO4 soft-packed battery. The project uses conjugated organic polymers in SPEs and creates an avenue to develop flexible energy storage equipment.

Extremely fast vortex dynamics in Bi2Sr2Ca2Cu3O10+δ crystalline nanostrip

The maximum velocity of a mobile vortex in movement is generally limited by the phenomenon of flux-flow instability (FFI), which necessitates weak vortex pinning and fast heat removal from non-equilibrium electrons. We here demonstrate exfoliations and nano-fabrications of Bi2Sr2Ca2Cu3O10+δ crystalline nanostrips, which possess a rather weak pinning volume of vortices, relatively low resistivity, and large normal electron diffusion coefficient. The deduced vortex velocity in Bi2Sr2Ca2Cu3O10+δ crystalline nanostrips can be up to 300 km/s near the superconducting transition temperature, well above the speed of sound. The observed vortex velocity is an order of magnitude faster than that of conventional superconducting systems, representing a perfect platform for exploration of ultra-fast vortex matter and a good candidate for fabrications of superconducting nanowire single photon detectors or superconducting THz modulator.

A topographic atlas defines developmental origins of cell heterogeneity in the human embryonic lung

The lung contains numerous specialized cell types with distinct roles in tissue function and integrity. To clarify the origins and mechanisms generating cell heterogeneity, we created a comprehensive topographic atlas of early human lung development. Here we report 83 cell states and several spatially resolved developmental trajectories and predict cell interactions within defined tissue niches. We integrated single-cell RNA sequencing and spatially resolved transcriptomics into a web-based, open platform for interactive exploration. We show distinct gene expression programmes, accompanying sequential events of cell differentiation and maturation of the secretory and neuroendocrine cell types in proximal epithelium. We define the origin of airway fibroblasts associated with airway smooth muscle in bronchovascular bundles and describe a trajectory of Schwann cell progenitors to intrinsic parasympathetic neurons controlling bronchoconstriction. Our atlas provides a rich resource for further research and a reference for defining deviations from homeostatic and repair mechanisms leading to pulmonary diseases.

Femtosecond laser direct writing multilayer chiral waveplates with minimal linear birefringence.

Chirality transfer from femtosecond laser direct writing in achiral transparent materials mainly originates from the interplay between anisotropic nanogratings and mechanical stress with non-parallel and non-perpendicular (oblique) neutral axes. Yet, the laser fabrication simultaneously induces non-negligible linear birefringence. For precise manipulation of circular polarization properties, as well as to unlock the full functionality, we report here a geometry-inspired multilayer method for direct writing of chiral waveplates with minimal linear birefringence. We perform a theoretical analysis of both circular and linear properties response for different multilayer configurations and achieve strong circular birefringence of up to -2.25 rad with an extinction ratio of circular birefringence to total linear birefringence of up to 5.5 dB at 550 nm. Our strategy enables the precise control of circular properties and provides a facile platform for chiral device exploration with almost no linear property existence.

Upregulation of non-canonical and canonical inflammasome genes associates with pathological features in Krabbe disease and related disorders.

Infantile Krabbe disease is a rapidly progressive and fatal disorder of myelin, caused by inherited deficiency of the lysosomal enzyme β-galactocerebrosidase. Affected children lose their motor skills and other faculties; uncontrolled seizures are a frequent terminal event. Overexpression of the sphingolipid metabolite psychosine is a pathogenic factor, but does not fully account for the pleiotropic manifestations and there is a clear need to investigate additional pathological mechanisms. We examined innate immunity, caspase-11 and associated inflammatory pathways in twitcher mice, an authentic model of Krabbe disease. Combined use of molecular tools, RNAscope in situ hybridization and immunohistochemical staining established that the expression of pro-inflammatory non-canonical caspase-11, canonical caspase-1, gasdermin D and cognate genes is induced in nervous tissue. Early onset and progressive upregulation of these genes accompany demyelination and gliosis and although the molecules are scant in healthy tissue, abundance of the respective translation products is greatly increased in diseased animals. Caspase-11 is found in reactive microglia/macrophages as well as astrocytes but caspase-1 and gasdermin D are restricted to reactive microglia/macrophages. The inflammasome signature is not unique to Krabbe disease; to varying degrees, this signature is also prominent in other lysosomal diseases, Sandhoff and Niemann-Pick Type-C1, and the lysolecithin toxin model of focal demyelination. Given the potent inflammatory response here identified in Krabbe disease and the other neurodegenerative disorders studied, a broad induction of inflammasomes is likely to be a dominant factor in the pathogenesis, and thus represents a platform for therapeutic exploration.

Interconnectedness: Entangled curation and dance in unsettled landscapes: An interview with DACE

DACE is a platform for curatorial and choreographic explorations on dance and choreography in a more-than-human world, founded by Rickard Borgström and Rebecca Chentinell. Central to the duo is how the body functions as an interface towards the surroundings. Consequently, they collaborate with artists engaged in the rapid environmental, technological and political changes, exploring a multitude of bodily approaches in questioning how these affect our actions, thinking and artistic practices. DACE traces new bodily sensitivities and interconnections between human, technology and nature in a more-than-human environment. DACE seeks new aesthetic paradigms in the shifting nature of ecological systems in the geological era of human-made nature. Since 2019, DACE has created gatherings, symposiums, developed as well as presented exhibitions and art works in different media and contexts. The works are exploring ecological and technological planes in theatres and galleries, an exploration of what post-human dance can be in a postanthropocentric worldview. The questions are posed by curator and choreographer Karina Sarkissova in a meeting of three independent dance curators based in Sweden and Finland.

Second-order topological magneto-optical effects in noncoplanar antiferromagnets

The second-order magneto-optical effects, represented by Voigt and Sch\"{a}fer-Hubert effects, are effective methods to detect the spin textures in antiferromagnets, whereas the previous studies are usually limited to collinear antiferromagnets. In noncollinear antiferromagnets, the spin textures characterized by spin chirality have been revealed to play a critical role in many exciting physics. In particular, the first-order topological magneto-optical effects originated from scalar spin chirality have been discovered recently. In this work, using the first-principles calculations and group theory analysis, we generalize the first-order topological magneto-optical effects to the second-order cases, that is, topological Voigt and Sch\"{a}fer-Hubert effects, by taking the noncoplanar 3Q spin state of $\gamma$-Fe$_{x}$Mn$_{1-x}$ alloy as an example. The conventional Voigt and Sch\"{a}fer-Hubert effects are comparatively studied in the collinear 1Q and 2Q spin states of $\gamma$-Fe$_{x}$Mn$_{1-x}$ alloy. In addition, the natural linear birefringence due to crystal anisotropy is discussed in the strained 1Q, 2Q, and 3Q states, and a unique fingerprint for experimentally distinguishing the second-order topological magneto-optical effects and natural linear birefringence is identified. Our work brings a topological insight into the second-order magneto-optical effects in noncoplanar antiferromagnets and also provides $\gamma$-Fe$_{x}$Mn$_{1-x}$ as an attractive material platform for future experimental exploration.

E-TSN: an interactive visual exploration platform for target-disease knowledge mapping from literature.

Target discovery and identification processes are driven by the increasing amount of biomedical data. The vast numbers of unstructured texts of biomedical publications provide a rich source of knowledge for drug target discovery research and demand the development of specific algorithms or tools to facilitate finding disease genes and proteins. Text mining is a method that can automatically mine helpful information related to drug target discovery from massive biomedical literature. However, there is a substantial lag between biomedical publications and the subsequent abstraction of information extracted by text mining to databases. The knowledge graph is introduced to integrate heterogeneous biomedical data. Here, we describe e-TSN (Target significance and novelty explorer, http://www.lilab-ecust.cn/etsn/), a knowledge visualization web server integrating the largest database of associations between targets and diseases from the full scientific literature by constructing significance and novelty scoring methods based on bibliometric statistics. The platform aims to visualize target-disease knowledge graphs to assist in prioritizing candidate disease-related proteins. Approved drugs and associated bioactivities for each interested target are also provided to facilitate the visualization of drug-target relationships. In summary, e-TSN is a fast and customizable visualization resource for investigating and analyzing the intricate target-disease networks, which could help researchers understand the mechanisms underlying complex disease phenotypes and improve the drug discovery and development efficiency, especially for the unexpected outbreak of infectious disease pandemics like COVID-19.

A Capsid Structure of Ralstonia solanacearum podoviridae GP4 with a Triangulation Number T = 9.

GP4, a new Ralstonia solanacearum phage, is a short-tailed phage. Few structures of Ralstonia solanacearum phages have been resolved to near-atomic resolution until now. Here, we present a 3.7 Å resolution structure of the GP4 head by cryo-electron microscopy (cryo-EM). The GP4 head contains 540 copies of major capsid protein (MCP) gp2 and 540 copies of cement protein (CP) gp1 arranged in an icosahedral shell with a triangulation number T = 9. The structures of gp2 and gp1 show a canonical HK97-like fold and an Ig-like fold, respectively. The trimeric CPs stick on the surface of the head along the quasi-threefold axis of the icosahedron generating a sandwiched three-layer electrostatic complementary potential, thereby enhancing the head stability. The assembly pattern of the GP4 head provides a platform for the further exploration of the interaction between Ralstonia solanacearum and corresponding phages.

MicroRNA-like RNA Functions Are Required for the Biosynthesis of Active Compounds in the Medicinal Fungus Sanghuangporus vaninii.

miRNA-like RNAs (milRNAs) have been recognized as sequence-specific regulators of posttranscriptional regulation of gene expression in eukaryotes. However, the functions of hundreds of fungal milRNAs in the biosynthesis of metabolic components are obscure. Sanghuangporus produces diverse bioactive compounds and is widely used in Asian countries. Here, genes encoding two Dicers, four Argonautes, and four RdRPs were identified and characterized in Sanghuangporus vanini. Due to the lack of an efficient gene manipulation system, the efficacy of spray-induced gene silencing (SIGS) was determined in S. vanini, which showed efficient double-stranded RNA (dsRNA) uptake and gene silencing efficiency. SIGS-mediated gene knockdown showed that SVRDRP-3, SVRDRP-4, SVDICER-1, and SVDICER-2 were critical for mycelial biomass, flavonoid, triterpenoid, and polysaccharide production. Illumina deep sequencing was performed to characterize the milRNAs from S. vanini mycelium and fruiting body. A total of 31 milRNAs were identified, out of which, SvmilR10, SvmilR17, and SvmilR33 were Svrdrp-4- and Svdicer-1-dependent milRNAs. Importantly, SIGS-mediated overexpression of SvmilR10 and SvmilR33 resulted in significant changes in the yields of flavonoids, triterpenoids, and polysaccharides. Further analysis showed that these milRNA target genes encoding the retrotransposon-derived protein PEG1 and histone-lysine N-methyltransferase were potentially downregulated in the milRNA overexpressing strain. Our results revealed that S. vanini has high external dsRNA and small RNA uptake efficiency and that milRNAs may play crucial regulatory roles in the biosynthesis of bioactive compounds. IMPORTANCE Fungi can take up environmental RNA that can silence fungal genes with RNA interference, which prompts the development of SIGS. Efficient dsRNA and milRNA uptake in S. vanini, successful dsRNA-targeted gene block, and the increase in intracellular miRNA abundance showed that SIGS technology is an effective and powerful tool for the functional dissection of fungal genes and millRNAs. We found that the RdRP, Dicer, and Argonaute genes are critical for mycelial biomass and bioactive compound production. Our study also demonstrated that overexpressed SVRDRP-4- and SVDICER-1-dependent milRNAs (SvmilR10 and SvmilR33) led to significant changes in the yields of the three active compounds. This study not only provides the first report on SIGS-based gene and milRNA function exploration, but also provides a theoretical platform for exploration of the functions of milRNAs involved in biosynthesis of metabolic compounds in fungi.

Lipopolysaccharide induced intestinal epithelial injury: a novel organoids-based model for sepsis in vitro.

Advances in organoid culture technology have provided a greater understanding of disease pathogenesis, which has been rarely studied in sepsis before. We aim to establish a suitable organoids-based intestinal injury model for sepsis. Stable passaged organoids were constructed and pre-treated with lipopolysaccharide (LPS) to mimic sepsis-induced intestinal injury. The LPS-induced sepsis model was used as a reference. We used quantitative real-time polymerase chain reaction to evaluate the RNA levels of inflammatory factors and antimicrobial peptides. Enzyme-linked immunosorbent assay was used to evaluate the protein levels, hematoxylin and eosin staining was used to evaluate the pathology of the small intestine of mice, and immunohistochemistry and immunofluorescence were used to evaluate the intestinal epithelial barrier function. Perkin Elmer Operetta™ was used to obtain high-resolution images of three-dimensional organoids. An LPS concentration >150 μg/mL after 24 h was identified to cause organoid growth restriction. The fluorescence intensity of zonula occludens-1 and occludins at LPS concentrations >100 μg/mL decreased significantly after 24 h. After LPS stimulation for 8 h, the RNA expression levels of interleukin (IL)-1α, tumor necrosis factor alpha, granulocyte-macrophage colony-stimulating factor, IL-6, and regenerating islet-derived protein 3 alpha, beta, and gamma increased. These results resembled those of intestinal epithelial layer alterations in a mouse sepsis model. For IL-10, the RNA expression level increased only when the LPS level >200 μg/mL for 24 h. This study provides the primary intestinal in vitro model to study the effects of LPS-induced intestinal injury resembling sepsis. This model provides a platform for immune associated mechanism exploration and effective drug screening.

PlantExp: a platform for exploration of gene expression and alternative splicing based on public plant RNA-seq samples.

Over the last decade, RNA-seq has produced a massive amount of plant transcriptomic sequencing data deposited in public databases. Reanalysis of these public datasets can generate additional novel hypotheses not included in original studies. However, the large data volume and the requirement for specialized computational resources and expertise present a barrier for experimental biologists to explore public repositories. Here, we introduce PlantExp (https://biotec.njau.edu.cn/plantExp), a database platform for exploration of plant gene expression and alternative splicing profiles based on 131423 uniformly processed publicly available RNA-seq samples from 85 species in 24 plant orders. In addition to two common retrieval accesses to gene expression and alternative splicing profiles by functional terms and sequence similarity, PlantExp is equipped with four online analysis tools, including differential expression analysis, specific expression analysis, co-expression network analysis and cross-species expression conservation analysis. With these online analysis tools, users can flexibly customize sample groups to reanalyze public RNA-seq datasets and obtain new insights. Furthermore, it offers a wide range of visualization tools to help users intuitively understand analysis results. In conclusion, PlantExp provides a valuable data resource and analysis platform for plant biologists to utilize public RNA-seq. datasets.

Structure-Reactivity Relationships of Buchwald-Type Phosphines in Nickel-Catalyzed Cross-Couplings.

The dialkyl-ortho-biaryl class of phosphines, commonly known as Buchwald-type ligands, are among the most important phosphines in Pd-catalyzed cross-coupling. These ligands have also been successfully applied to several synthetically valuable Ni-catalyzed cross-coupling methodologies and, as demonstrated in this work, are top performing ligands in Ni-catalyzed Suzuki Miyaura Coupling (SMC) and C-N coupling reactions, even outperforming commonly employed bisphosphines like dppf in many circumstances. However, little is known about their structure-reactivity relationships (SRRs) with Ni, and limited examples of well-defined, catalytically relevant Ni complexes with Buchwald-type ligands exist. In this work, we report the analysis of Buchwald-type phosphine SRRs in four representative Ni-catalyzed cross-coupling reactions. Our study was guided by data-driven classification analysis, which together with mechanistic organometallic studies of structurally characterized Ni(0), Ni(I), and Ni(II) complexes allowed us to rationalize reactivity patterns in catalysis. Overall, we expect that this study will serve as a platform for further exploration of this ligand class in organonickel chemistry as well as in the development of new Ni-catalyzed cross-coupling methodologies.

Human reliability assessment and risk prediction for deep submergence operating system of manned submersible under the influence of cognitive performance

The manned submersible is the main platform for precise deep-sea exploration. The cognitive states of different levels generated when the submerged members in the vehicle are faced with changes in external factors, such as environmental characteristics and operational tasks at different operation stages, will have a dynamic impact on work efficiency and human reliability. Based on the CREAM method and Bayesian network, this study proposed a human reliability assessment method and risk prediction technology for deep submergence operating system. Firstly, the extended CREAM method was corrected again by introducing the cognitive performance correction coefficient. Secondly, the weights of common performance conditions (CPCs) and cognitive effectiveness influence system (CEIS) were adaptively calibrated by using the DEMATEL method. Finally, the Bayesian assessment network for human reliability of deep submergence operating system was constructed to assess the human reliability of each operation stage and the overall system. This method is helpful for the overall design of the manned deep submergence research institute, and it can accurately identify and interdict the key risk points for relevant technicians of system security engineering, so as to reduce the safety risk of deep submergence operating system and improve the working efficiency of the man-machine system in cabin.

Intuitively visualizing spatial data from biogeographic assessments: A 3-dimensional case study on remotely sensing historic shipwrecks and associated marine life

Biogeographic assessments aim to determine spatial and temporal distributions of organisms and habitats to help inform resource management decisions. In marine systems, rapid technological advances in sensors employed for biogeographic assessments allow scientists to collect unprecedented volumes of data, yet it remains challenging to visually and intuitively convey these sometimes massive spatial or temporal data as actionable information in geographically relevant maps or virtual models. Here, we provide a case study demonstrating an approach to bridge this data visualization gap by displaying coastal ocean data in a 3D, interactive online format. Our case study documents a workflow that provides resource managers, stakeholders, and the general public with a platform for direct exploration of and interaction with 3D data from hydrographically mapping shipwrecks and marine life on the continental shelf of North Carolina, USA. We simultaneously mapped shipwrecks and their associated fish using echosounders. A multibeam echosounder collected high-resolution multibeam bathymetry of the shipwrecks and detected the broad extent of fish schools. A calibrated splitbeam echosounder detected individual fish and fish schools. After processing the echosounder data, we built an interactive, online 3D data visualization web application complemented by multimedia and story text using ESRI geographic information systems. The freely available visual environment, called “Living Shipwrecks 3D,” allows direct engagement with the biogeographic assessment data in a customizable format. We anticipate that additional interactive 3D data applications can be constructed using a similar workflow allowing seamless exploration of complex spatial data used in biogeographic assessments.

α−As2Te3 as a platform for the exploration of the electronic band structure of single layer β−tellurene

Arsenic telluride, ${\mathrm{As}}_{2}{\mathrm{Te}}_{3}$, is a layered van der Waals (vdW) semiconducting material usually known for its thermoelectric properties. It is composed of layers stacked together via weak vdW interactions, which can consequently be exfoliated into thin two-dimensional layers. Here, we studied the electronic properties of the $\ensuremath{\alpha}$ phase of ${\mathrm{As}}_{2}{\mathrm{Te}}_{3}$ by using angle-resolved photoemission spectroscopy (ARPES) and density-functional theory (DFT). In addition to the spectroscopic signature of $\ensuremath{\alpha}\ensuremath{-}{\mathrm{As}}_{2}{\mathrm{Te}}_{3}$, we were able to isolate anisotropic 2D electronic states, decoupled from the $\ensuremath{\alpha}\ensuremath{-}{\mathrm{As}}_{2}{\mathrm{Te}}_{3}$ electronic structure, that we propose to ascribe to single layer (SL) $\ensuremath{\beta}\ensuremath{-}\mathrm{tellurene}$. Our findings are supported by theoretical investigations using DFT, which reproduce the main ARPES experimental features. Our work thereby proposes $\ensuremath{\alpha}\ensuremath{-}{\mathrm{As}}_{2}{\mathrm{Te}}_{3}$ (100) surface as an interesting platform for the experimental exploration of the electronic band structure of SL $\ensuremath{\beta}\ensuremath{-}\mathrm{tellurene}$, which has been difficult to experimentally access otherwise.

Assessing approaches to learning with nonparametric multidimensional scaling.

This article reports on a trace-based assessment of approaches to learning used by middle school aged children who interacted with NASA Mars Mission science, technology, engineering and mathematics (STEM) games in Whyville, an online game environment with 8 million registered young learners. The learning objectives of two games included awareness and knowledge of NASA missions, developing knowledge and skills of measurement and scaling, applying measurement for planetary comparisons in the solar system. Trace data from 1361 interactions were analysed with nonparametric multidimensional scaling methods, which permitted visual examination and statistical validation, and provided an example and proof of concept for the multidimensional scaling approach to analysis of time-based behavioural data from a game or simulation. Differences in approach to learning were found illustrating the potential value of the methodology to curriculum and game-based learning designers as well as other creators of online STEM content for pre-college youth. The theoretical framework of the method and analysis makes use of the Epistemic Network Analysis toolkit as a post hoc data exploration platform, and the discussion centres on issues of semantic interpretation of interaction end-states and the application of evidence centred design in post hoc analysis.