Exploring the affordances of telepresence robots in foreign language learning

The importance of authentic communicative practices in foreign language (FL) learning has long been recognized. However, most FL learners lack adequate access to authentic communicative environments in the target language. In this article, we propose the use of telepresence robots as a potential solution to bridge this gap. Telepresence robots can be controlled by remote language learners online, enabling them to gain virtual access to authentic environments in the target language and to interact with native speakers in those environments in real time. In this exploratory study, three English learners and a native-speaker of American English participated in a campus tour activity using a telepresence robot. We examined the experience of our participants and the conversational features of their telepresence interactions through analyses of the interview data, field notes, and transcripts of conversations captured on video. Our findings show that telepresence robots have substantial potential for promoting FL learning by providing authentic communicative practice for remote language learners. The findings have useful implications for informing future research design

Evaluating AIGC Detectors on Code Content

Artificial Intelligence Generated Content (AIGC) has garnered considerable attention for its impressive performance, with ChatGPT emerging as a leading AIGC model that produces high-quality responses across various applications, including software development and maintenance. Despite its potential, the misuse of ChatGPT poses significant concerns, especially in education and safetycritical domains. Numerous AIGC detectors have been developed and evaluated on natural language data. However, their performance on code-related content generated by ChatGPT remains unexplored. To fill this gap, in this paper, we present the first empirical study on evaluating existing AIGC detectors in the software domain. We created a comprehensive dataset including 492.5K samples comprising code-related content produced by ChatGPT, encompassing popular software activities like Q&A (115K), code summarization (126K), and code generation (226.5K). We evaluated six AIGC detectors, including three commercial and three open-source solutions, assessing their performance on this dataset. Additionally, we conducted a human study to understand human detection capabilities and compare them with the existing AIGC detectors. Our results indicate that AIGC detectors demonstrate lower performance on code-related data compared to natural language data. Fine-tuning can enhance detector performance, especially for content within the same domain; but generalization remains a challenge. The human evaluation reveals that detection by humans is quite challenging

Characterization and expression patterns of a membrane-bound trehalase from Spodoptera exigua

<p>Abstract</p> <p>Background</p> <p>The chitin biosynthesis pathway starts with trehalose in insects and the main functions of trehalases are hydrolysis of trehalose to glucose. Although insects possess two types, soluble trehalase (Tre-1) and membrane-bound trehalase (Tre-2), very little is known about Tre-2 and the difference in function between Tre-1 and Tre-2.</p> <p>Results</p> <p>To gain an insight into trehalase functions in insects, we investigated a putative membrane-bound trehalase from <it>Spodoptera exigua </it>(SeTre-2) cloned from the fat body. The deduced amino acid sequence of SeTre-2 contains 645 residues and has a predicted molecular weight of ~74 kDa and p<it>I </it>of 6.01. Alignment of SeTre-2 with other insect trehalases showed that it contains two trehalase signature motifs and a putative transmembrane domain, which is an important characteristic of Tre-2. Comparison of the genomic DNA and cDNA sequences demonstrated that <it>SeTre-2 </it>comprises 13 exons and 12 introns. Southern blot analysis revealed that <it>S. exigua </it>has two trehalase genes and that <it>SeTre-2 </it>is a single-copy gene. Northern blot analyses showed that the <it>SeTre-2 </it>transcript is expressed not only in the midgut, as previously reported for <it>Bombyx mori</it>, but also in the fat body and Malpighian tubules, although expression patterns differed between the midgut and fat body. <it>SeTre-2 </it>transcripts were detected in the midgut of feeding stage larvae, but not in pupae, whereas <it>SeTre-2 </it>mRNA was detected in the fat body of fifth instar larvae and pupae.</p> <p>Conclusion</p> <p>These findings provide new data on the tissue distribution, expression patterns and potential function of membrane-bound trehalase. The results suggest that the <it>SeTre-2 </it>gene may have different functions in the midgut and fat body.</p

VarArray Meets t-SOT: Advancing the State of the Art of Streaming Distant Conversational Speech Recognition

This paper presents a novel streaming automatic speech recognition (ASR) framework for multi-talker overlapping speech captured by a distant microphone array with an arbitrary geometry. Our framework, named t-SOT-VA, capitalizes on independently developed two recent technologies; array-geometry-agnostic continuous speech separation, or VarArray, and streaming multi-talker ASR based on token-level serialized output training (t-SOT). To combine the best of both technologies, we newly design a t-SOT-based ASR model that generates a serialized multi-talker transcription based on two separated speech signals from VarArray. We also propose a pre-training scheme for such an ASR model where we simulate VarArray's output signals based on monaural single-talker ASR training data. Conversation transcription experiments using the AMI meeting corpus show that the system based on the proposed framework significantly outperforms conventional ones. Our system achieves the state-of-the-art word error rates of 13.7% and 15.5% for the AMI development and evaluation sets, respectively, in the multiple-distant-microphone setting while retaining the streaming inference capability.Comment: 6 pages, 2 figure, 3 tables, v2: Appendix A has been adde

Low-Cost Smart Antenna Using Active Frequency Selective Surfaces

Smart antenna is a key technology for advanced wireless systems and one of the most important features of smart antenna is electronically beam scanning or switching. It is highly desirable to reduce the mass, power consumption and cost of smart antennas, as the traditional phased array is always associated with high cost due to the use of many T/R modules and complicated beamforming network (BFN). This paper presents the University of Kent's recent research progress in the field of low-cost smart antenna design using active frequency selective surfaces (AFSS). Firstly, this paper presents a brief review of AFSS based beam-reconfigurable antenna including several recent designs reported by the authors' group. Then, a new high-gain AFSS antenna design with some preliminary results will be presented. This is design achieves higher gain than the reported AFSS antennas. A detailed list of references is given at the end of this paper

A Compact Monopole Antenna With Filtering Response for WLAN Applications

A novel compact monopole antenna with filtering response for WLAN applications is presented in this paper. The antenna is composed of a capacity-loaded matching patch, two resonators, and two end-coupled monopoles. The resonators consist of wide rectangular patches and narrow shorted lines to form the resonance, and the resonators are printed on the different layers to increase the design flexibility. Two meandering monopoles are located at the edges of the top layer with capacitive coupling at each other's end. The mutual couplings between the meander monopoles are utilized to produce two radiation nulls at the two band-edges. Based on the design method, the prototype of the proposed antenna was designed, fabricated and measured. The measured results show that the antenna has a broad bandwidth of 16% for S 11 <; -10 dB. Also, ideal omnidirectional radiation patterns, and steep band-edge selectivity with two radiation nulls are achieved for the proposed antenna

Pregnane X receptor is required for interleukin-6-mediated down-regulation of cytochrome P450 3A4 in human hepatocytes

Cytochrome P450 3A4 (CYP3A4) is the most abundant cytochrome P450 enzyme in human liver and metabolizes more than 60% of prescribed drugs in human body. Patients with liver conditions such as cirrhosis show increased secretion of cytokines (e.g., interleukin-6) and decreased capacity of oxidation of many drugs. In this study, we provided molecular evidence that cytokine secretion directly contributed to the decreased capacity of oxidative biotransformation in human liver. After human hepatocytes were treated with IL-6, the expression of CYP3A4 decreased at both mRNA and protein levels, so did the CYP3A4 enzymatic activity. Meanwhile, the repression of CYP3A4 by IL-6 occurred after the decrease of pregnane X receptor (PXR) in human hepatocytes. The PXR-overexpressed cells (transfected with human PXR) increased the CYP3A4 mRNA level, and the repression of CYP3A4 by IL-6 was greater in the PXR-overexpressed cells than in the control cells. Further, PXR knockdown (transfected with siPXR construct) decreased the CYP3A4 mRNA level with less repression by IL-6 than in the control cells transfected with corresponding vector. Collectively, our study suggests that PXR is necessary for IL-6-mediated repression of the CYP3A4 expression in human hepatocytes

A Wideband Series-Fed Circularly Polarized Differential Antenna by Using Crossed Open Slot-Pairs

A novel method of designing a wideband series-fed circularly polarized (CP) differential antenna by using crossed open slot-pairs is presented in this paper. The near-field distributions and input impedance analyses show that the closely spaced open slot-pairs can radiate as the crossed dipoles and have stable radiating resistance with a compact radiator size. Besides, a wideband half-power phase shifter by using open slot is proposed and utilized to realize CP radiation. The proposed CP antenna is composed of a wide slot-pair and a narrow slot-pair. In the antenna design, the narrow slot-pair is not only excited as a radiator, but also elaborately loaded to provide wideband half-power output and quadrature phase excitation to the wide slot-pair. Both the proposed half-power phase shifter and CP antenna are illustrated by the corresponding equivalent circuits. Based on these analyses, the proposed antenna is designed, fabricated and measured. Compared to the simulated traditionally designed counterpart, 2.1 times wider axial ratio bandwidth is achieved for the proposed antenna. The measured overlapped bandwidth for axial ratio 10 dB is 1.95-3.45 GHz (55.6%). Also, the antenna gain and radiation patterns are measured, which agree well with the simulated results

A Dual-Polarized Planar Antenna Array Differentially-Fed by Orthomode Transducer

This paper presents a new design of a differentially-fed substrate integrated planar antenna array with dual-polarization. Compared with the traditional dual-polarized antenna arrays, the proposed array antenna has the advantages of simple configuration, high cross-polarization discrimination (XPD) and high gain. 2×2-element subarray design with a vialoaded crossover structure is used, which reduces the complexity of the array antenna. The operation bandwidth is improved by generating three resonances in the subarray. One 8×8 antenna array is designed, prototyped and tested to exemplify its potential applications in large dual-polarized antenna arrays. A planar orthomode transducer is used to achieve differential excitation for the antenna array. The measured results show that the proposed antenna array has an impedance bandwidth of 19.2–20.7 GHz for |S11| < −10 dB and port isolation higher than 20 dB. The array antenna exhibits a high XPD of 43 dB and a flat gain about 22.2 dBi within the bandwidth