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This paper systematically reviews 150 (VR/AR)-supporting language learning articles from 2008 to 2019 and summarizes the development trends. The definition of VR/AR is given firstly, and then the model of VR/AR supporting learning is proposed. This model's language types, research participants, learning devices, learning goals, research issues, research methods, research domains and learning strategies act as a coding scheme here. Meanwhile, through review and analysis, empirical study has been proven to be in its peak period; the VR/AR is increasingly applied, and larger numbers of immersive devices are being used. Under such circumstances, higher education is the principal of research, and speaking/expressing and words are still the most significant learning goals. As for research issues, the first period (2008-2013), which focuses more on learners' opinions, learning behaviours, learning attitudes and learning performance, is still the main scheme even though the second period (2014-2019) has more research issues and wider research scale. Right now, research about teaching and learning has already drawn the most attention, and task-based learning, situated learning, and game-based learning are the most commonly used learning strategies. Finally, this paper analyses VR/AR used in language learning through SWOT analysis to provide more profound suggestions and further discussion.

Virtual-reality 3D modeling helps primary school students to develop creative thinking and problem-solving skills. Through hands-on practice, students can understand abstract concepts more intuitively, and can realize the combination of theory and practice. However, in conventional virtual 3D modeling teaching, students often lack immersive modeling experience, and the modeling method may not be in line with the cognitive way of thinking of primary school students, which, in turn, causes high cognitive load. Immersive virtual reality (IVR) environments provide students with more immersive and intuitive interactions, which can help promote students' cognitive, emotional, and social development. Therefore, this study combined IVR with 3D virtual modeling to form an immersive virtual-reality-based 3D modeling approach (IVR-based 3D modeling) and designed a quasi-experiment to compare it with the conventional virtual reality 3D modeling approach (CVR-based 3D modeling) to explore its effectiveness. The results of the study show that the IVR-based 3D modeling approach significantly enhanced elementary school students' creative thinking, including its sub-dimensions (e.g., challenge, imagination, and curiosity), when compared to the CVR-based 3D modeling approach. The same conclusion was reached for problem-solving skills. IVR-based 3D modeling also reduced students' cognitive load during the learning process, especially in terms of mental effort. The results of the interviews complement the experimental results, and the learners' perceptions of the new approach explain the experimental results to some extent. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical potential and safety of Moluodan to reverse gastric precancerous lesions. Methods: Patients aged 18–70 years diagnosed with moderate‐to‐severe atrophy and/or moderate‐to‐severe intestinal metaplasia, with or without low‐grade dysplasia, and negative for Helicobacter pylori were recruited in this randomized, double‐blind, parallel‐controlled trial. The primary outcome was the improvement of global histological diagnosis at 1‐year follow‐up endoscopy using the operative link for gastritis assessment, the operative link for gastric intestinal metaplasia assessment, and the disappearance rate of dysplasia. Results: Between November 3, 2017 and January 27, 2021, 166 subjects were randomly assigned to the Moluodan group, 168 to the folic acid group, 84 to the combination group, and 84 to the high‐dose Moluodan group. The improvement in global histological diagnosis was achieved in 60 (39.5%) subjects receiving Moluodan, 59 (37.8%) receiving folic acid, 26 (32.1%) receiving the combined drugs, and 36 (47.4%) receiving high‐dose Moluodan. Moluodan was non‐inferior to folic acid (95% confidence interval: −9.2 to 12.5; P = 0.02). High‐dose Moluodan had a trend for better protective efficacy, though there was no statistical significance. The disappearance rate of dysplasia was 82.8% in the Moluodan group, which was superior to folic acid (53.9%; P = 0.006). No drug‐related serious adverse events were observed. Conclusions: One pack of Moluodan three times daily for 1 year was safe and effective in reversing gastric precancerous lesions, especially dysplasia. Doubling its dose showed a better efficacy trend. [ABSTRACT FROM AUTHOR]

Gut microbiome is integral to the pathogenesis of ulcerative colitis. A novel probiotic Lactobacillus intestinalis (L. intestinalis) exerts a protective effect against dextran sodium sulfate‐induced colitis in mice. Based on flow cytometry, colitis‐associated Th17 cells are the target of L. intestinalis, which is supported by the lack of protective effects of L. intestinalis in T cell‐null Rag1−/− mice or upon anti‐IL‐17‐A antibody‐treated mice. Although L. intestinalis exerts no direct effect on T cell differentiation, it decreases C/EBPA‐driven gut epithelial SAA1 and SAA2 production, which in turn impairs Th17 cell differentiation. Cometabolism of L. intestinalis ALDH and host ALDH1A2 contributed to elevated biosynthesis of retinoic acid (RA), which accounts for the anti‐colitis effect in RAR‐α ‐mediated way. In a cohort of ulcerative colitis patients, it is observed that fecal abundance of L. intestinalis is negatively associated with the C/EBPA‐SAA1/2‐Th17 axis. Finally, L. intestinalis has a synergistic effect with mesalazine in alleviating murine colitis. In conclusion, L. intestinalis and associated metabolites, RA, have potential therapeutic effects for suppressing colonic inflammation by modulating the crosstalk between intestinal epithelia and immunity. [ABSTRACT FROM AUTHOR]

This paper systematically reviews 150 (VR/AR)-supporting language learning articles from 2008 to 2019 and summarizes the development trends. The definition of VR/AR is given firstly, and then the model of VR/AR supporting learning is proposed. This model's language types, research participants, learning devices, learning goals, research issues, research methods, research domains and learning strategies act as a coding scheme here. Meanwhile, through review and analysis, empirical study has been proven to be in its peak period; the VR/AR is increasingly applied, and larger numbers of immersive devices are being used. Under such circumstances, higher education is the principal of research, and speaking/expressing and words are still the most significant learning goals. As for research issues, the first period (2008–2013), which focuses more on learners' opinions, learning behaviours, learning attitudes and learning performance, is still the main scheme even though the second period (2014–2019) has more research issues and wider research scale. Right now, research about teaching and learning has already drawn the most attention, and task-based learning, situated learning, and game-based learning are the most commonly used learning strategies. Finally, this paper analyses VR/AR used in language learning through SWOT analysis to provide more profound suggestions and further discussion. [ABSTRACT FROM AUTHOR]

Catalytic tandem cyclization of ynamides has attracted considerable interest in organic synthesis because of its atom economy in the rapid formation of polycyclic compounds. However, examples on the construction of pentacyclic spiroindolines are quite scarce. Herein, we described a BiCl3‐mediated tandem cyclization reaction of tryptamine‐ynamides, which led to the formation of appealing pentacyclic spiroindoline scaffolds in moderate to excellent yields. In addition, such a reaction can lead to the divergent synthesis of tricyclic indole derivatives with moderate yields by engineering substrate structures. The synthetic utility of this methodology has also been demonstrated by further interesting transformations. [ABSTRACT FROM AUTHOR]

An interesting β‐isoquinidine catalyzed divergent reaction was developed to produce either spirocyclopentene oxindoles, spirocyclopentadiene oxindoles or bisoxindoles in a high enantioselective fashion. The utility of this protocol was demonstrated by the versatile transformations of the products. This work not only represents the first highly stereoselective intermolecular catalytic asymmetric allylic alkylation reaction between two isatin‐derived MBH carbonate molecules but also constitutes a rare example of isatin‐derived MBH carbonate‐based enantioselective and α‐regioselective [3+2] cycloaddition reactions. [ABSTRACT FROM AUTHOR]

A general method is proposed to describe the energy levels of the interface states in one-dimensional photonic crystal (PC) heterojunction ([ (A B) m (C D) m ] n) containing dispersive or non-dispersion materials. We found that the finite energy levels of the interface states for the finite configuration can be described totally by the dispersion relation of the PC with a periodic unit [ (A B) m (C D) m ]. It is further found that this method is also applicable for the case of defect modes. We believe our method can be used to guide the practical application. [ABSTRACT FROM AUTHOR]

The development of catalytic enantioselective isocyanide‐based reactions is currently of great interest because the resulting products are valuable in organic synthesis, pharmacological chemistry, and materials science. This review assembles and comprehensively summarizes the recent achievements in this rapidly growing area according to the reaction types. Special attention is paid to the advantages, limitations, possible mechanisms, and synthetic applications of each reaction. In addition, a personal outlook on the opportunities for further exploration is given at the end. [ABSTRACT FROM AUTHOR]

Out-of-focus blur is a common image degradation phenomenon that occurs in case of lens defocusing. The out-of-focus blur kernel is usually modeled as a Gaussian function or a uniform disk in previous work. In this paper, we propose that it can be more accurately depicted using the generalized Gaussian (GG) function. This is motivated by the theoretical analysis of the out-of-focus blur and the practical observation of real blur kernels. We show that as the out-of-focus blur kernels are of specific shapes, the GG function can be further simplified to a single-parameter model. We estimate the parameter of the GG blur kernel from image patches containing step edges, and obtain the clear image by non-blind image deblurring. Experimental results validate that the proposed GG blur kernel estimation algorithm outperforms the state-of-the-art ones deploying either parametric (disk and Gaussian) or nonparametric kernels, and consequently benefits the image deblurring process. [ABSTRACT FROM AUTHOR]

We have developed a palladium‐catalyzed cross‐coupling reaction of isocyanides with α‐diazoacetates to form active ketenimines and following a 1,4‐diazabicyclo[2.2.2]octane (DABCO) catalyzed aza‐Mannich type reaction with various 2‐mercaptoimidazoles for the synthesis of 1,3‐bis(β‐aminoacrylate)‐substituted 2‐mercaptoimidazole derivatives with structural diversity. In addition, the use of 1H‐benzo[d]imidazol‐2‐ol as the reaction partner also allowed the formation of 1,3‐bis(β‐aminoacrylate)‐substituted 2‐benzimidazolinone derivatives with moderate yields (34–52%). In the aza‐Mannich reaction, the regioselective N‐attack rather than S‐attack or O‐attack at the electrophilic central carbon of ketenimines was observed. This tandem sequence is efficient since two C=C and two C−N bonds are consecutively created in one‐pot. [ABSTRACT FROM AUTHOR]

Multispectral imaging plays a vital role in the area of computer vision and computational photography. As spectral band images can be misaligned due to imaging device movement or alternation, image registration is necessary to avoid spectral information distortion. The current registration measures specialized for multispectral data are typically robust yet complex, requiring excessive computation. The common measures such as sum of squared differences (SSD) and sum of absolute differences (SAD) are computationally efficient whereas they perform poorly on multispectral data. To cope with this challenge, we propose a structure consistency boosting (SCB) transform that aims at boosting the structural similarity of multispectral images. With SCB, the common measures can be employed for multispectral image registration. The SCB transform exploits the fact that inherent edge structures maintain relative saliency locally despite the nonlinear variation between band images. A statistical prior of the natural image, which is based on the gradient-intensity correlation, is explored to build a parametric form of SCB. Experimental results validate that the SCB transform outperforms current similarity enhancement algorithms, and performs better than the state-of-the-art multispectral registration measures. Thanks to the generality of the statistical prior, the SCB transform is also applicable to various multimodal data such as flash/no-flash images and medical images. [ABSTRACT FROM AUTHOR]

Tandem reactions of Pd‐catalyzed cross‐coupling of 3‐(2‐isocyanoethyl)indoles with diazoacetates and subsequent spirocyclization/Mannich‐type reaction have been developed to assemble polycyclic spiroindoline skeletons. Formation of spiroindolenines has been proven as the crucial step for the following Mannich‐type cyclization reaction. Accordingly, a novel approach on chiral phosphoric acid catalyzed Mannich‐type cyclization toward the formation of diastereomerically and enantiomerically enriched pentacyclic spiroindolines has been established. Moreover, the products of the reaction are versatile building blocks in synthetic chemistry, as demonstrated by the synthesis of the key framework of aspidosperma and kopsia alkaloids. [ABSTRACT FROM AUTHOR]

A newly developed template protection-sacrifice (TPS) strategy is developed for the synthesis of hollow yolk–shell Co@CN with a large surface area and high pore volume. The catalyst exhibits excellent catalytic efficiency in base-free oxidative esterification of 5-hydroxymethylfurfural under mild conditions with excellent selectivity at a high concentration (2 M) of the reactant. [ABSTRACT FROM AUTHOR]

Background and Aims. Hydrotalcite plays an important role in the therapy of gastric ulcer induced by nonsteroidal anti-inflammatory drugs (NSAIDs), but little is known about the mechanism. We designed two experiments to study the preventive and curative effects of hydrotalcite on NSAIDs-related gastric injury in rats and to investigate the relationship between the protective and curative mechanism of hydrotalcite and the secretion of epidermal growth factor (EGF)/prostaglandin E2 (PGE2). Methods. Two experiments were separately designed to evaluate the preventive and curative effects of hydrotalcite. A total of 25 male rats and 25 female rats were randomly divided into five groups (vehicle group, model group, omeprazole group, hydrotalcite group, and ranitidine group) in each experiment. Rats were treated with indomethacin by gavage to build the model of acute gastric mucosal injury. The concentrations of EGF and PGE2 in blood specimens and mucosal injury indexes by gross inspection were measured and an immunohistochemical technique was also employed to test the levels of EGF, cyclooxygenase-1 (COX-1), and cyclooxygenase-2 (COX-2) in gastric mucosa. Results. Comparing with model group in both preventive and curative experiments, hydrotalcite decreased the gastric injury in the mucosa of stomach significantly (7±4.5 vs. 16±11.25, 1.5±2 vs. 2.5±6; P<0.01, P<0.05). The levels of EGF and PGE2 in blood serum were markedly higher in hydrotalcite group than that in model group and ranitidine group in preventive experiment (574.39±34.28 vs. 486.22±41.73, 488.07±24.44; P<0.01, P<0.01). The expression levels of COX-2 in gastric mucosa were also higher in hydrotalcite group than that in model group in both preventive and therapeutic experiments (12±4 vs. 9±6, 14±7 vs. 9±4; P<0.01, P<0.05). Conclusions. Hydrotalcite promotes gastric protection and healing via several mechanisms, including increased levels of PGE2 in blood serum, activation of EGF, and antagonising the inhibition of cyclooxygenase (COX) caused by NSAIDs. [ABSTRACT FROM AUTHOR]

Multispectral imaging system is of wide application in relevant fields for its capability in acquiring spectral information of scenes. Its limitation is that, due to the large number of spectral channels, the imaging process can be quite time-consuming when capturing high-resolution (HR) multispectral images. To resolve this limitation, this paper proposes a fast multispectral imaging framework based on the image sensor pixel-binning and spectral unmixing techniques. The framework comprises a fast imaging stage and a computational reconstruction stage. In the imaging stage, only a few spectral images are acquired in HR, while most spectral images are acquired in low resolution (LR). The LR images are captured by applying pixel binning on the image sensor, such that the exposure time can be greatly reduced. In the reconstruction stage, an optimal number of basis spectra are computed and the signal-dependent noise statistics are estimated. Then the unknown HR images are efficiently reconstructed by solving a closed-form cost function that models the spatial and spectral degradations. The effectiveness of the proposed framework is evaluated using real-scene multispectral images. Experimental results validate that, in general, the method outperforms the state of the arts in terms of reconstruction accuracy, with additional $20\times $ or more improvement in computational efficiency. [ABSTRACT FROM PUBLISHER]

A highly regioselective protocol for the direct synthesis of γ,δ-unsaturated ketones from β-ketoacids and allylic alcohols was proposed and accomplished relying on the combination of [Ir(cod)Cl]2 and 10-camphorsulfonic acid via decarboxylative allylation. [ABSTRACT FROM AUTHOR]

Keywords: [3+2] cycloaddition; cascade reactions; catalytic asymmetric; insertion reaction; isocyanide EN [3+2] cycloaddition cascade reactions catalytic asymmetric insertion reaction isocyanide 1 1 1 04/19/21 20210416 NES 210416 B The development of catalytic b enantioselective isocyanide-based reactions leading to products, which are valuable in organic synthesis, pharmacological chemistry, and materials science is currently of great interest. [3+2] cycloaddition, cascade reactions, catalytic asymmetric, insertion reaction, isocyanide Recent achievements in this rapidly growing area according to the reaction types, with special attention being paid to the advantages, limitations, possible mechanisms, and synthetic applications of each reaction is given in the Review by Y.-L. [Extracted from the article]

While indoles are regioselectively mono-methylated at C-3, pyrroles give mixtures of mono-, di-, and (in the case of unsubstituted pyrrole) polymethylated products. [ABSTRACT FROM AUTHOR]

The presented approach allows direct usage of allylic alcohols as starting material without prior activation. [ABSTRACT FROM AUTHOR]

A diagram is presented which shows the quinolines synthesis from allylic alcohols through tandem isomerization/cyclization of catalyzed iridium combined with potassium hydroxide.

Depending on the base, a wide range of α,β-unsaturated ketones are reduced to saturated ketones or alcohols by using a simple homogeneous catalytic system based on the commercially available Iridium catalyst under optimized reaction conditions. [ABSTRACT FROM AUTHOR]