142 research outputs found

    MUSIED: A Benchmark for Event Detection from Multi-Source Heterogeneous Informal Texts

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    Event detection (ED) identifies and classifies event triggers from unstructured texts, serving as a fundamental task for information extraction. Despite the remarkable progress achieved in the past several years, most research efforts focus on detecting events from formal texts (e.g., news articles, Wikipedia documents, financial announcements). Moreover, the texts in each dataset are either from a single source or multiple yet relatively homogeneous sources. With massive amounts of user-generated text accumulating on the Web and inside enterprises, identifying meaningful events in these informal texts, usually from multiple heterogeneous sources, has become a problem of significant practical value. As a pioneering exploration that expands event detection to the scenarios involving informal and heterogeneous texts, we propose a new large-scale Chinese event detection dataset based on user reviews, text conversations, and phone conversations in a leading e-commerce platform for food service. We carefully investigate the proposed dataset's textual informality and multi-source heterogeneity characteristics by inspecting data samples quantitatively and qualitatively. Extensive experiments with state-of-the-art event detection methods verify the unique challenges posed by these characteristics, indicating that multi-source informal event detection remains an open problem and requires further efforts. Our benchmark and code are released at \url{https://github.com/myeclipse/MUSIED}.Comment: Accepted at EMNLP 202

    Effects of the interaction between shade and drought on physiological characteristics in Calamus viminalis seedlings

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    Recently, the endangerment of wild rattan population draws attention on the conservation and sustainable utilization of rattan resources. Rattan growing usually faces the light and water stress. Therefore, we aim to explore the combined effects of shade and drought on seedling growth, thus providing a theoretical ground for the conservation and artificial cultivation of the rattan. The combined effects of shade and drought on physiological and biochemical traits were studied in two-years-old Calamus viminalis seedlings. Photosynthetic indices including Pn, Gs, Tr, and Ci and physiological indices including MDA, SOD, POD, CAT, and Pro were measured under four levels of water treatments and four levels of shade. Shade, drought and their interaction have a significant effect on C. viminalis seedlings growth. Generally, moderate shade could alleviate the impact induced by drought. However, mild drought usually enhances the effect caused by shading. The result showed that the shade decreased Pn, Gs, and Tr but increased Ci, MDA content and Pro content. Either with the shading or drought increasing, the activity of SOD, POD, and CAT firstly increase and then declined. Drought reduced Pn, Gs, Tr, and Ci but increased the content of MDA and Pro. Overall, the result suggests that 25-50% shading and 65% RSWC water treatment are most beneficial for the growth of C. viminalis seedlings

    Finite automaton intrusion tolerance system model based on Markov

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    To ensure that the system could still provide normal service for legitimate users when the LAN being invaded,a finite automaton intrusion tolerance model was designed.Based on Markov’s theory,the state transformation relationship of the service provided by the system by establishing the state transition probability matrix was described,quantified the transition state and found the key nodes in the system.The maintenance of key nodes could enhance the tolerance of the system and improve the reliability of the service.Experimental comparison shows that this model not only has strong intrusion tolerance,but also has obvious advantages in the integrity of the security system when it is invaded

    Leishmania donovani visceral leishmaniasis diagnosed by metagenomics next-generation sequencing in an infant with acute lymphoblastic leukemia: a case report

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    BackgroundVisceral leishmaniasis (VL) is a neglected vector-borne tropical disease caused by Leishmania donovani (L. donovani) and Leishmania infantum (L. infantum). Due to the very small dimensions of the protozoa impounded within blood cells and reticuloendothelial structure, diagnosing VL remains challenging.Case presentationHerein, we reported a case of VL in a 17-month-old boy with acute lymphoblastic leukemia (ALL). The patient was admitted to West China Second University Hospital, Sichuan University, due to repeated fever after chemotherapy. After admission, chemotherapy-related bone marrow suppression and infection were suspected based on clinical symptoms and laboratory test results. However, there was no growth in the conventional peripheral blood culture, and the patient was unresponsive to routine antibiotics. Metagenomics next-generation sequencing (mNGS) of peripheral blood identified 196123 L. donovani reads, followed by Leishmania spp amastigotes using cytomorphology examination of the bone marrow specimen. The patient was given pentavalent antimonials as parasite-resistant therapy for 10 days. After the initial treatment, 356 L. donovani reads were still found in peripheral blood by mNGS. Subsequently, the anti-leishmanial drug amphotericin B was administrated as rescue therapy, and the patient was discharged after a clinical cure.ConclusionOur results indicated that leishmaniasis still exists in China. Unbiased mNGS provided a clinically actionable diagnosis of a specific infectious disease from an uncommon pathogen that eluded conventional testing

    Two-level mixed-effects height to crown base model for moso bamboo (Phyllostachys edulis) in Eastern China

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    Height to crown base (HCB) is an important predictor variable for forest growth and yield models and is of great significance for bamboo stem utilization. However, existing HCB models built so far on the hierarchically structured data are for arbor forests, and not applied to bamboo forests. Based on the fitting of data acquired from 38 temporary sample plots of Phyllostachys edulis forests in Yixing, Jiangsu Province, we selected the best HCB model (logistic model) from among six basic models and extended it by integrating predictor variables, which involved evaluating the impact of 13 variables on HCB. Block- and sample plot-level random effects were introduced to the extended model to account for nested data structures through mixed-effects modeling. The results showed that bamboo height, diameter at breast height, total basal area of all bamboo individuals with a diameter larger than that of the subject bamboo, and canopy density contributed significantly more to variation in HCB than other variables did. Introducing two-level random effects resulted in a significant improvement in the accuracy of the model. Different sampling strategies were evaluated for response calibration (model localization), and the optimal strategy was identified. The prediction accuracy of the HCB model was substantially improved, with an increase in the number of bamboo samples in the calibration. Based on our findings, we recommend the use of four randomly selected bamboo individuals per sample to provide a compromise between measurement cost, model use efficiency, and prediction accuracy

    A pediatric case of anti-GABABR encephalitis: case report and literature review

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    Background and objectiveThis study aims to analyze the clinical characteristics of anti-GABABR encephalitis in pediatric patients. Due to its rarity and diagnostic challenges in children, we compare clinical features between adult and pediatric cases.Materials and methodsUsing the key words “anti-GABABR encephalitis, children, autoimmune encephalitis, limbic encephalitis”, we conduct a comprehensive literature review of all studies related to anti-GABABR encephalitis published from January 2010 to January 2024. A total of 207 cases are identified globally, including 14 pediatric cases.ResultsWe report a case of an 8-year-and-6-month-old child with anti-GABABR encephalitis presenting with abnormal mental behavior (irritability, hallucinations), sleep disorders, and paroxysmal involuntary limb movements. Serum anti-GABABR antibodies were positive, and clinical symptoms improved significantly after corticosteroid treatment. Analysis reveal that children presented with mental/behavioral abnormalities as the initial symptom (85.71%), while adults presented with epileptic seizures as the initial symptom (76.71%). Main symptoms include epilepsy in adults (78.24%) and sleep disorders (26.67%) and involuntary limb movements (33.33%) in children. Neuroimaging shows higher involvement of the basal ganglia (55.56%), cerebellar hemispheres (22.22%), and brainstem (22.22%) in children compared to adults. Video electroencephalogram (EEG) analysis indicates more frequent abnormal EEG in adults, but epileptic waves are more common in children with abnormal EEG. Cerebrospinal fluid (CSF) cytology is not specific, with mild lymphocytic increases (adults 57.98% vs. children 33.33%, P = 0.2054). Despite higher prodromal fever rates in children (66.67% vs. 23.44%, P = 0.0228), they respond better to immunotherapy. No tumor-related issues are observed in pediatric cases, contrasting with 58.09% tumor comorbidity in adults.ConclusionsThis study suggests that the clinical phenotypes of anti-GABABR encephalitis in children and adults may differ: children are more likely to present with mental and behavioral abnormalities (the initial symptom trend), sleep disorders and involuntary movements (the main symptoms), and their brain imaging is more likely to involve regions such as the basal ganglia and brainstem, and they respond better to immunotherapy. Notably, due to the small sample size of pediatric cases (n = 15) compared to adult cases (n = 193), these comparative findings should be interpreted with caution despite the statistical significance indicated by P-values. However, long-term follow-up remains essential

    A Statistical Study of Solar White-Light Flares Observed by the White-light Solar Telescope of the Lyman-alpha Solar Telescope on the Advanced Space-based Solar Observatory (ASO-S/LST/WST) at 360 nm

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    Solar white-light flares (WLFs) are those accompanied by brightenings in the optical continuum or integrated light. The White-light Solar Telescope (WST), as an instrument of the Lyman-alpha Solar Telescope (LST) on the Advanced Space-based Solar Observatory (ASO-S), provides continuous solar full-disk images at 360 nm, which can be used to study WLFs. We analyze 205 major flares above M1.0 from October 2022 to May 2023 and identify 49 WLFs at 360 nm from WST observations, i.e. with an occurrence rate of 23.9%. The percentages of WLFs for M1 - M4 (31 out of 180), M5 - M9 (11 out of 18), and above X1 (7 for all) flares are 17.2%, 61.1%, and 100%, respectively, namely the larger the flares, the more likely they are WLFs at 360 nm. We further analyze 39 WLFs among the identified WLFs and investigate their properties such as white-light enhancement, duration, and brightening area. It is found that the relative enhancement of the white-light emission at 360 nm is mostly (>90%) less than 30% and the mean enhancement is 19.4%. The WLFs' duration at 360 nm is mostly (>80%) less than 20 minutes and its mean is 10.3 minutes. The brightening area at 360 nm is mostly (>75%) less than 500 arcsecond2 and the median value is 225. We find that there exist good correlations between the white-light enhancement/duration/area and the peak soft X-ray (SXR) flux of the flare, with correlation coefficients of 0.68, 0.58, and 0.80, respectively. In addition, the white-light emission in most WLFs peaks around the same time as the temporal derivative of SXR flux as well as the hard X-ray emission at 20 - 50 keV, indicative of Neupert effect. It is also found that the limb WLFs are more likely to have a greater enhancement, which is consistent with numerical simulations

    Spectral and Imaging Observations of a C2.3 White-Light Flare from the Advanced Space-Based Solar Observatory (ASO-S) and the Chinese Hα\alpha Solar Explorer (CHASE)

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    Solar white-light flares are characterized by an enhancement in the optical continuum, which are usually large flares (say X- and M-class flares). Here we report a small C2.3 white-light flare (SOL2022-12-20T04:10) observed by the \emph{Advanced Space-based Solar Observatory} and the \emph{Chinese Hα\alpha Solar Explorer}. This flare exhibits an increase of \approx6.4\% in the photospheric Fe \textsc{i} line at 6569.2\,\AA\ and {\approx3.2\%} in the nearby continuum. The continuum at 3600\,\AA\ also shows an enhancement of \approx4.7\%. The white-light brightening kernels are mainly located at the flare ribbons and co-spatial with nonthermal hard X-ray sources, which implies that the enhanced white-light emissions are related to nonthermal electron-beam heating. At the brightening kernels, the Fe \textsc{i} line displays an absorption profile that has a good Gaussian shape, with a redshift up to \approx1.7 km s1^{-1}, while the Hα\alpha line shows an emission profile though having a central reversal. The Hα\alpha line profile also shows a red or blue asymmetry caused by plasma flows with a velocity of several to tens of km s1^{-1}. It is interesting to find that the Hα\alpha asymmetry is opposite at the conjugate footpoints. It is also found that the CHASE continuum increase seems to be related to the change of photospheric magnetic field. Our study provides comprehensive characteristics of a small white-light flare that help understand the energy release process of white-light flares.Comment: 23 pages, 6 figures, accepted by Solar Physic

    Comparative transcriptomic and metabolomic analysis reveals mechanisms of selenium-regulated anthocyanin synthesis in waxy maize (Zea mays L.)

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    Anthocyanins in maize (Zea mays L.) kernels determine the plant’s color and can enhance its resistance. Selenium (Se) significantly impacts plant growth, development, and secondary metabolic regulation. However, the molecular mechanisms by which Se regulates anthocyanin synthesis in waxy corn remain unclear. This study employed integrated transcriptomic and metabolomic analyses to investigate the mechanisms through which selenium influences anthocyanin synthesis in yellow and purple waxy corn. The results showed that maize varieties with higher anthocyanin content had higher selenium enrichment capacity in their kernels. Under selenium stress, HN2025 exhibited 1,904 more differentially expressed genes (DEGs) and 140 more differential metabolites compared to HN5. The expression levels of anthocyanin synthesis-related genes and transcription factors such as phenylalanine ammonia-lyase, flavonoid 3-hydroxylase (F3H), dihydroflavonol reductase (DFR), chalcone synthase (CHS), cinnamate-4-hydroxylase (C4H), anthocyanin 5,3-O-glucosyltransferases, and anthocyanidin reductase, MYB, and bHLH were strongly induced in HN2025. Metabolomic analysis revealed significant enrichment in anthocyanin biosynthesis, flavonoid and flavonol biosynthesis, glutathione metabolism, phenylalanine biosynthesis, and phenylalanine metabolism under selenium treatment. Three up-regulated PAL genes and one C4H gene were significantly enriched with DAMs in phenylalanine metabolism, phenylpropanoid biosynthesis, flavonoid biosynthesis, and anthocyanin biosynthesis, resulting in significant differences between HN5 and HN2025 in selenium-induced anthocyanin metabolism-related pathways. These findings provide a theoretical basis for understanding the effects of selenium on the molecular regulatory mechanisms of anthocyanin biosynthesis in maize kernels
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