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Online and online‐merge‐offline learning are promoting the sharing of teaching resources and the transformation of teaching and learning methods during the global epidemic. However, uneven learning resources, subject‐based classification, and incomplete result‐based evaluation always make it hard for students to keep pace with the ideal teaching objectives. Based on the theory of cognitive style and teaching style, the LPSA video classification consisting of linguistic type (L), presentative type (P), scientific type (S), and artistic type (A), is proposed to realize teaching quality evaluation and learning process detection. In addition, eight subdimensions of LPSA and its quantitative methods utilizing multimedia processing and AI algorithm are introduced to realize video classification. By automatically generating the threshold map and developing related real‐time video evaluating tools, the technical and applied feasibility of the proposed LPSA is certified, which could also facilitate student's personal learning and accurate teaching evaluation. [ABSTRACT FROM AUTHOR]

Emotion cause extraction (ECE) task that aims at extracting potential trigger events of certain emotions has attracted extensive attention recently. However, current work neglects the implicit emotion expressed without any explicit emotional keywords, which appears more frequently in application scenarios. The lack of explicit emotion information makes it extremely hard to extract emotion causes only with the local context. Moreover, an entire event is usually across multiple clauses, while existing work merely extracts cause events at clause level and cannot effectively capture complete cause event information. To address these issues, the events are first redefined at the tuple level and a span‐based tuple‐level algorithm is proposed to extract events from different clauses. Based on it, a corpus for implicit emotion cause extraction that tries to extract causes of implicit emotions is constructed. The authors propose a knowledge‐enriched joint‐learning model of implicit emotion recognition and implicit emotion cause extraction tasks (KJ‐IECE), which leverages commonsense knowledge from ConceptNet and NRC_VAD to better capture connections between emotion and corresponding cause events. Experiments on both implicit and explicit emotion cause extraction datasets demonstrate the effectiveness of the proposed model. [ABSTRACT FROM AUTHOR]

Summary: Re‐establishment of heritable latitudinal clines in growth‐related traits has been recognised as evidence for adaptive evolution in invasive plants. However, less information is known about latitudinal clines in defence and joint clinal evolution of growth and defence in invasive plants.We planted 14 native Argentinean populations and 14 introduced Chinese populations of Alternanthera philoxeroides in replicate common gardens in China. We investigated the latitudinal clines of traits related to growth and defence, and plasticity of these traits in relation to experiment site and soil nitrogen.We found that chemical defence decreased with latitude in introduced populations but increased with latitude in native populations. For growth rate, latitudinal clines were positive in introduced populations but nonexistent in native populations. There were also parallel positive latitudinal clines in total/shoot biomass and specific leaf area. Experiment site affected the occurrence or magnitude of latitudinal clines in growth rate, branch intensity and triterpenoid saponins concentration. Introduced populations were more plastic to experiment site and soil nitrogen than native populations.We provide evidence for rapid evolution of clines in growth and defence in an invasive plant. Altered herbivory gradients and trade‐off between growth and defence may explain nonparallel clines between the native and introduced ranges. [ABSTRACT FROM AUTHOR]

ABSTRACT Two series of novel electro-optic (EO) polycarbonates containing two different kinds of nonlinear optical (NLO) chromophores with tricyanofurane (TCF) electron acceptor have been successfully prepared through the facile polycondensation between diol NLO chromophore and bisphenol A bis(chloroformate). These new polycarbonates which were characterized by 1H-NMR and Fourier transform infrared exhibited good solubility in common polar organic solvents. They also showed glass transition temperatures ( Tg) in the range of 124-156 °C. The morphology studies indicated that these polycarbonates had good film quality before and after corona poling. The EO coefficients ( r33) of two polycarbonates films were up to 45 pm/V (PC-TCFC-2) and 75 pm/V (PC-DFTC-3) at the wavelength of 1310 nm. Moreover, good temporal stability of the poling-induced dipole alignment was also achieved, and the resulting poled films of PC-TCFC-2 and PC-DFTC-3 could retain 90 and 80% of the initial EO activities at 85 °C for more than 500 h, respectively. Both EO activity and temporal stability results were better than the guest-host EO polymers containing the same concentration chromophores, which indicated that such kind of polycarbonates could effectively suppress the intermolecular electrostatic interaction and translate microscopic molecular hyperpolarizability into macroscopic EO activity. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2013, 51, 2841-2849. [ABSTRACT FROM AUTHOR]

A new nonlinear optical chromophore with strong electron-withdrawing acceptor and rigid-flexible dendron was synthesized. An electro-optic (EO) attenuated total reflectance modulator was prepared to measure the EO coefficient of the films. Modification of the tricyanopyrroline chromophore with rigid-flexible dendron group provided reduction of dipole-dipole interactions and improvement of its solubility. As the chromophore loading increased, there was a great improvement on the macroscopic EO response of the polymeric materials obtained by incorporating this chromophore as a guest in amorphous polycarbonate. The largest EO coefficient was 42 pm/V at 1310 nm. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]