Search Results (737)

Chinese cloze question generation for educational assessments requires identifying gap phrases that accurately reflect key knowledge points, posing significant challenges to automated systems. We observe that the syntactic boundaries revealed by part-of-speech (POS) tags closely align with the semantic boundaries of target gap phrases. Motivated by this observation, we propose a multi-task learning framework in which gap phrase identification serves as the primary task and POS tagging as a complementary auxiliary task. The two tasks share a common BERT-BiLSTM encoder, enabling mutual reinforcement of both syntactic and semantic representations through joint training. To further capture the interaction between label semantics and contextual word representations, we introduce a label-attention mechanism that models dependencies between the global word sequence and candidate label embeddings. Additionally, we construct a refined POS tag subset by excluding categories whose boundaries show no alignment with gap phrase boundaries, thereby strengthening the correspondence between the two tasks. Evaluated on a real-world dataset of 20.5K questions spanning five academic disciplines, our method achieves an F1 score of 65.85%, with a Recall of 67.79%, representing improvements of 2.12% and 4.35% over the prior state-of-the-art, respectively. These results demonstrate that exploiting the alignment between syntactic and semantic structures through joint learning is effective for generating educationally meaningful fill-in-the-blank questions. Full article

Radio-frequency identification (RFID)-based asset tracking in cabinet environments often encounters unpredictable detection caused by multipath fading, metal-induced interference, and tag placement sensitivity, which can render single-band systems unreliable under real-world conditions. This paper proposes a dual-band detection approach combining 915 MHz and 2.45 GHz to address these challenges through frequency diversity. Unlike designs confined to closely spaced UHF bands, this method uses a larger spectral gap to benefit from uncorrelated fading and distinct propagation properties. Theoretical analysis shows that dual-band detection significantly reduces joint failure probability under independent fading. The proposed framework is implemented using commercially available passive UHF tags at 915 MHz and an active RFID tag/reader at 2.45 GHz. The two systems are operated sequentially along the same guided scan path, and their detected tag-ID sets are combined offline using an OR-fusion rule without hardware-level synchronization. Across trials with varied scan speeds, power levels, reader distances, and tag placements, single-band detection fell below 50% under double-speed scanning at 200 cm, while the dual-band method remained above 70% and, in many cases, reached 100% reliability. Performance trends are further analyzed across individual scenarios, showing that 2.45 GHz links are less affected by metallic shadowing at close range, whereas 915 MHz links maintain more stable detection at longer distances. These findings are discussed in terms of deployment feasibility, indicating that the additional hardware and configuration requirements are offset by the measurable improvement in detection consistency, making the approach applicable for inventory tracking in logistics, warehousing, and industrial automation. Full article

This paper investigates the feasibility of 3D self-localization and tracking using chipless radio frequency identification (RFID) tags operating in the terahertz (THz) frequency band. The primary objective is to achieve sub-millimeter (sub-mm) localization and tracking accuracy while minimizing reliance on external infrastructure. To this end, a hybrid localization framework is proposed that jointly exploits round-trip time-of-flight (RToF) and angle-of-arrival (AoA) measurements to enhance localization performance. Although near-field propagation effects are inherently significant in the considered THz operating regime, a simplified far-field approximation is adopted to facilitate tractable system modeling and analytical development. The proposed framework is further extended to dynamic scenarios through an extended Kalman filter (EKF)-based tracking algorithm, which incorporates temporal state evolution to improve estimation robustness under noisy measurements. Furthermore, the Cramér–Rao lower bound (CRLB) for the hybrid RToF-AoA system is derived to establish the fundamental limits of localization accuracy under varying system configurations and measurement conditions. Simulation results demonstrate that the proposed approach is capable of achieving sub-mm localization and tracking accuracy with a highly constrained anchor infrastructure, including operation with a single anchor in the considered scenario. These findings highlight the potential of THz chipless RFID technology as a promising enabling solution for next-generation high-accuracy localization and tracking applications. Full article

Introduction: Fish stock identification and delineation are fundamental requirements for preventing local depletion and promoting the sustainable exploitation of marine resources. The blackspot seabream, Pagellus bogaraveo, is the most commercially valuable sparid species across the Northeast Atlantic and the Mediterranean Sea. To effectively discriminate fish stocks, researchers increasingly rely on the use of natural tags, which reflect both environmental and genetic influences, providing critical information regarding fish movements and population structure. Objective: To broaden the understanding of P. bogaraveo stock structure, samples originally obtained for a parasite-based discrimination study were used to provide complementary insights through otolith shape and geochemical signatures. Methodology: A subset of 150 individuals (30 per location) collected across five Portuguese locations (Portugal mainland: Matosinhos, Figueira da Foz, and Sagres; and Archipelagos: Azores and Madeira) was selected for otolith analyses. Otolith contour phenotypic variation was quantified through Elliptical Fourier Descriptors (EFDs) and Shape Indices (SIs), while elemental signatures (element: Ca) were analyzed using solution-based inductively coupled plasma mass spectrometry (SB-ICP-MS). Statistical analyses involved both univariate (one-way ANOVA, followed by Tukey tests, if needed) and multivariate approaches (MANOVA and LDFA), considering both individual and combined datasets. Results: EFDs + SIs yielded the lowest discriminatory power, with an overall reclassification accuracy of 38%. In contrast, Ca signatures provided the highest discrimination at 79%. The combination of both markers resulted in a slightly lower overall accuracy of 75%, likely due to the higher variance associated with the morphological data. Conclusions: In agreement with the previous parasite assessment, these otolith-based approaches confirm that the Macaronesian archipelagos consist of distinct stocks, separate from the Portuguese continental shelf. Furthermore, significant differences in otolith geochemical signatures between Sagres and Figueira da Foz point to a further subdivision of stocks. These findings are consistent with recent genetic data identifying three distinct stocks along the western and southern Iberian Peninsula, reinforcing the need for localized management of P. bogaraveo populations to ensure long-term fishery sustainability. Full article

Human milk cream, a lipid-rich fraction obtained during milk defatting, is typically discarded despite its potential for individualized nutritional strategies. This study evaluated the effects of Holder pasteurization (HoP) and storage conditions (refrigeration and freezing) on the microbiological profile and lipid stability of human milk–derived cream. Cream fractions from six mothers of preterm infants were analyzed for bacterial counts using Columbia Nalidixic Acid and MacConkey agar, with isolate identification by MALDI-TOF MS, and for lipid stability through free fatty acids (FFAs), triacylglycerol (TAGs) composition by GC-FID, and peroxide values (PV) determined by a rapid photometric method. Raw cream showed stable total bacterial counts across storage conditions, with a reduction in Gram-negative bacteria after freezing, while HoP samples exhibited no detectable bacterial growth. Lipolysis was significantly higher in raw cream, with increased FFAs after 72 h refrigeration, whereas HoP samples maintained lower and more stable FFA levels. TAG profiles remained largely stable under refrigeration but were significantly altered during frozen storage in raw samples, suggesting membrane disruption and selective hydrolysis; these changes were attenuated in HoP samples. PV increased over time in both groups, indicating progressive primary lipid oxidation, although values remained within moderate ranges. Overall, HoP improved microbiological safety and lipid stability, supporting the potential use of human milk cream as a controlled lipid source for individualized fortification in preterm infants. Full article

Biomolecular condensates in the cytoplasm and nucleus contribute to carcinogenesis through aberrant signaling by assorted transcription factors and fusion oncoproteins. Oral cancer, which is highly prevalent worldwide, frequently occurs in a U-shaped “high-risk” zone (floor of mouth, side of tongue, and anterior fauces) which forms the path of liquid transit through the mouth. We previously reported that environmental stresses of saliva-like hypotonicity and beverage-like temperature changes triggered cycles of disassembly/reassembly of biomolecular condensates of GFP-tagged human myxovirus resistance protein (MxA; alias Mx1) in oral cancer cells. In the present study, we identified some of the constituents of GFP-MxA cytoplasmic condensates in oral cells. These condensates were isolated from interferon (IFN)-λ1-treated GFP-MxA expressing OECM1 human oral cancer cells using magnetic bead-based immunoisolation. Unbiased peptide identification confirmed the presence of MxA/Mx1 peptides; however, the strongest intensity was for the BACH1 transcription factor family. Immunofluorescence analyses confirmed the association of BACH1 and the family member Nrf2 with cytoplasmic human GFP-MxA condensates. Moreover, GFP-BACH1 and GFP-Nrf2 colocalized with cytoplasmic human HA-MxA condensates in transiently transfected OECM1 cells. Western blot assays confirmed the presence of BACH1 and Nrf2 proteins in complexes isolated using anti-MxA pAb. As much as BACH1 and Nrf2 regulate oxidative stress response genes, it was remarkable that immunofluorescence assays revealed the presence of heme oxygenase 1 (HO1)—a downstream redox regulator—in GFP-MxA condensates. However, these condensates were devoid of p62, KEAP1 and Cul3. In terms of aberrant function, in live cells, the Nrf2 transcription factor underwent rapid disassembly and reassembly cycles driven by saliva-like hypotonicity, and was also disassembled by sulforaphane. The data highlight the unexpected intersections in oral cells between MxA condensates and BACH1, Nrf2 and HO1—proteins well known to be involved in pathways regulating cellular responses to environmental and oxidative stresses, antiviral defense, oral epithelial dysplasia, and cancer progression and metastases. Full article

Radio frequency identification (RFID) technology has been widely adopted in a variety of practical applications. Usually, the size of a passive tag antenna largely determines the read performance of tag. However, excessively large tag antennas can hinder their practical application and a tag that is too small has poor performance. In this paper, a compact, flexible and corrosion-resistant folding dipole tag antenna is proposed, which has a geometrical dimension of 24 mm × 13 mm (0.074${\mathsf{\lambda }}_0\times 0.040{\mathsf{\lambda }}_0$). It is designed on only one surface of a flexible polyethylene terephthalate (PET) substrate, which can be folded. The paper proposes a single-sided laser-patterned GAF/PET flexible RFID tag that is mechanically folded to form a backside dipole arm without vias, targeting compact and corrosion-resistant UHF RFID operation. Changing the size of the folding arm can effectively adjust the resonant frequency and impedance of the tag antenna. A stepped radiation arm is used to extend the current path and lower the resonance frequency. The capacitance and inductance effects introduced by loading a T match for reducing the resonant frequency of the tag to the useful UHF RFID band. Finally, it can achieve a power transfer coefficient of 99.9% and exhibit high impedance matching between the tag antenna and the chip. The proposed tag antenna uses graphene-assembled film (GAF) as its conductor material. Thanks to the physicochemical properties of GAF, the proposed tag antenna maintains stable radiation performance even after prolonged exposure to acidic (5 wt%), alkaline (5 wt%), and salt (5 wt%) corrosion, as well as more than 1000 mechanical bending cycles. When the EIRP of the reader is 2.2 W, the maximum read range of the tag in the 800–1000 MHz is 1.38 m. Full article

Medical device manufacturing requires strict quality control, reliable traceability, and compliance with regulatory requirements. In many cases, inspection activities are still carried out manually and production information is recorded separately, which can result in inconsistent defect detection and limited visibility of manufacturing performance. This paper presents the development and industrial implementation of an integrated closed-loop quality control architecture for a sterile single-use medical device assembly line, addressing the lack of integration between inspection, traceability, and control systems in existing manufacturing approaches. In the proposed approach, we combine radio-frequency identification, machine vision inspection, programmable logic control, and centralized production monitoring. RFID tags store the status of each unit at individual stations so that defective products cannot proceed to downstream operations. Machine vision systems verify component presence, detect missing parts, and confirm color-specific assembly requirements during production. The architecture was tested through implementation on an assembly line and evaluated with comparative pilot studies against a traditional manual inspection process. The upgraded line achieved scrap cost reductions of 52.77% and 53.23% while also improving inspection consistency and production traceability. The results demonstrate that integrating machine vision inspection with RFID traceability can significantly improve quality control and manufacturing efficiency in regulated medical device production. Full article

Bacteroides fragilis is a major commensal bacterium of the human colon. However, enterotoxigenic B. fragilis (ETBF) secretes B. fragilis toxin (BFT), a zinc-dependent metalloprotease that cleaves E-cadherin and promotes chronic inflammation and colorectal tumorigenesis. Despite extensive research, the cellular receptor for BFT remains unidentified. In this study, we developed His-tagged recombinant BFT variants including both catalytically active and inactive forms to facilitate biochemical and functional analyses. Functional assays confirmed that the active variant retained proteolytic activity and induced characteristic cellular responses, while the inactive variant served as an effective negative control. These results establish a robust experimental platform for BFT receptor identification and mechanistic studies of BFT-host interactions. The active and inactive BFT variants provide essential molecular tools for investigating ETBF pathogenicity and developing therapeutic interventions. Full article

Bone marrow-derived mesenchymal stem cells (BMSCs), owing to their osteoblastogenic differentiation potential, are crucial for maintaining bone homeostasis and remodeling. Nevertheless, in aging and age-related bone diseases like osteoporosis, BMSCs show significantly diminished osteogenic potential, with a concomitant increase in adipogenic differentiation. The aged BMSCs also become desensitized to BMP2 stimulation to a large extent and exhibit aberrations in BMP2 signaling. However, the molecular mechanisms facilitating this shift in lineage commitment and mediating the cellular dysfunctions remain elusive. This knowledge gap hinders the development of regenerative strategies for skeletal aging and osteoporosis. This study employed an integrative tandem mass tag (TMT)-based phosphoproteomic and total proteomic profiling on BMSCs isolated from young (6-month) and aged (15-month) C57BL/6 (B6) mice to elucidate global alterations in both protein activity and expression. The analysis identified more than 500 proteins that underwent significant alterations (BH-adjusted p-value < 0.05) either in phosphorylation or expression between young and aged BMSCs. Many lineage-specific markers also underwent changes in both phosphorylation and expression with aging. Additionally, key biological processes, including cellular metabolism, clathrin-mediated endocytosis, and nucleocytoplasmic transport mechanisms, were enriched for the deregulated proteins. Signaling proteins, ERK-1/2, had increased activating phosphorylation in the aged BMSCs, while transcription factors Lrrfip1, Ruvbl1, and Ruvbl2 also exhibited dysregulated activity and abundance in the aged BMSCs. The findings from the study adds significant mechanistic insights into how aging disrupts signal transduction, metabolism, and transcriptional program in BMSCs, contributing to age-associated loss of bone mass and reduced skeletal regenerative capabilities. Through the identification of key mediators of BMSC dysfunction seen in aging, this work offers a strong foundation in devising potential therapeutic strategies to restore diminished osteogenic potential and treat osteoporosis. Full article

Within the framework of behavioral ecology and conservation, individual recognition plays a critical role in the research on wild social animals at the individual level. Traditional identification methods often rely on long-term field experience or invasive physical tagging. Recent advances in deep learning enable non-invasive individual recognition under natural conditions; however, the effectiveness of facial detection and identification depends on species-specific facial characteristics, environmental conditions, and dataset scale. In this study, we used 3385 images from 18 identified wild Tibetan macaques (Macaca thibetana) to develop an individual recognition system, TMacaque-FaceNet, integrating You Only Look Once (YOLO) for face detection and a Vision Transformer (ViT) for individual classification. The results showed that the Tibetan macaque face detector achieved a mAP@0.5 of 0.971, with a precision of 0.974 and a recall of 0.931. The individual recognizer for the wild Tibetan macaque social group achieved a top-1 accuracy of 96.33% on the test set. On an event-wise (temporal holdout) validation set comprising 90 images (5 images per individual), the recognizer achieved a top-1 accuracy of 95.56%. Gradient-weighted attention rollout analyses further revealed that the model focused on biologically meaningful facial regions, supporting the interpretability of the recognition process. Our results provide a new automated facial recognition method to non-invasively monitor Tibetan macaque individuals in natural environments. It provides a practical tool to facilitate automated behavioral observation, social network analysis, and long-term population monitoring of wild non-human primates. Full article

Named Entity Recognition (NER) plays a crucial role in Aspect-Based Sentiment Identification (ABSI), enabling the extraction of domain-specific aspects and their associated sentiment expressions from unstructured textual reviews. In complex domains such as movie reviews, sentiment is frequently conveyed through references to named entities (e.g., actors, directors, or movie titles) and other contextual cues. However, many existing ABSI approaches treat NER as a separate preprocessing step, limiting the effective modeling of entity–aspect–opinion relationships. Integrating NER directly into the ABSI framework, allows entity-specific opinions to be more accurately identified, overlapping aspects to be disambiguated, and contextual sentiment expressions to be captured more effectively. To address these challenges, this study proposes an integrated NER-based aspect identification model built on feature-enhanced LSTM and BiLSTM architectures. Linguistic features, including Parts-of-Speech (POS) tags and chunking information, are incorporated to enrich contextual representations, while a Conditional Random Field (CRF) decoding layer models inter-label dependencies for coherent sequence-level predictions of named entities, aspects, and associated opinion expressions. Compared with large transformer-based models, the proposed BiLSTM-CRF architecture offers lower computational complexity, fewer parameters, and allows explicit integration and analysis of linguistic features that are often implicitly encoded in transformer attention mechanisms. The model is evaluated through multiple experimental variants across three domains. Four configurations are applied to movie-review data to jointly extract person names, movie titles, and aspect-opinion pairs, while six configurations assess cross-domain robustness on restaurant and laptop review datasets. Results show that the BiLSTM-CRF model augmented with POS features consistently outperforms baseline configurations in the movie domain and remains competitive across domains, achieving an F1-score of 0.89. These findings demonstrate that explicit linguistic feature integration within a CRF-based sequence modeling can provide an effective and computationally efficient alternative to large-scale transformer fine-tuning for structured, entity-linked ABSI tasks. Full article

Reliable individual identification and minimally invasive tracking are essential for monitoring threatened snake populations. A relict high-altitude population of Vipera ursinii ursinii was studied in the Maiella National Park (Central Apennines, Italy) during two field seasons (2024–2025) to (i) validate dorsal head photo-identification against unequivocal PIT-tag identities and (ii) test a novel, non-invasive telemetry method based on externally attached harmonic diodes detected with a RECCO^® harmonic direction finder (HDF). All analysed snakes were PIT-tagged and photographed under standardised conditions. Manual photo-identification based on dorsal cephalic scale counts was performed independently by four blinded operators. In parallel, software-assisted photo-identification was conducted with two independent programmes (Wild-ID and Hotspotter). Both methods were evaluated exclusively against PIT-tag-confirmed identities. Manual identification achieved moderate-to-high overall accuracy (0.77–0.91) but showed marked inter-operator variability. Software-assisted matching appeared more consistent: Hotspotter identified 75% of true recaptures at first suggestion (85% within the top six suggestions), while Wild-ID identified 56% at first suggestion (88% within the top six). Correct matches were primarily supported by the distinctive pholidosis of the dorsal head region, especially apical, intercanthal and parafrontal scales—which were highly diverse but independent of sex and age class in the studied population. Externally attached HDF diodes enabled repeated short-term relocations with detachments occurring within hours to several days and mostly associated with ecdysis. The method was minimally invasive, supporting its applicability for monitoring small-bodied animals with low-density populations and restricted ranges. Full article

In this paper, inspired by the structural characteristics of the human eyeball, a bionically designed circular resonant structure is proposed, and a flexible chipless radio frequency identification (RFID) tag based on this concept is developed. By selectively adding or removing branch structures, the proposed tag achieves controllable resonant frequency shifts and distinguishable geometric pattern variations. Fabricated on a polyimide substrate with a compact size of 20 × 26 × 0.2 mm³, the tag achieves a coding capacity exceeding 45 bits while operating within an effective frequency bandwidth in 4–12 GHz, realizing a synergistic improvement in coding capacity and structural compactness under limited spectrum constraints. Simulation analyses are performed to investigate the encoding stability of the tag under various bending and rotational conditions relevant to flexible applications. Experimental results obtained under the unbent condition are consistent with the simulations, demonstrating the feasibility of the proposed chipless RFID tag. Full article

Differentiating AI-generated, real, or imitated artworks is becoming a tedious and computationally challenging problem in digital art analysis. AI-generated art has become nearly indistinguishable from human-made works, posing a significant threat to copyrighted content. This content is appearing on online platforms, at exhibitions, and in commercial galleries, thereby escalating the risk of copyright infringement. This sudden increase in generative images raises concerns like authenticity, intellectual property, and the preservation of cultural heritage. Without an automated, comprehensible system to determine whether an artwork has been AI-generated, authentic (real), or imitated, artists are prone to the reduction of their unique works. Institutions also struggle to curate and safeguard authentic pieces. As the variety of generative models continues to grow, it becomes a cultural necessity to build a robust, efficient, and transparent framework for determining whether a piece of art or an artist is involved in potential copyright infringement. To address these challenges, we introduce ArtUnmasked, a practical and interpretable framework capable of (i) efficiently distinguishing AI-generated artworks from real ones using a lightweight Spectral Artifact Identification (SPAI), (ii) a TagMatch-based artist filtering module for stylistic attribution, and (iii) a DINOv3–CLIP similarity module with patch-level correspondence that leverages the one-shot generalization ability of modern vision transformers to determine whether an artwork is authentic or imitated. We also created a custom dataset of ∼24K imitated artworks to complement our evaluation and support future research. The complete implementation is available in our GitHub repository. Full article