286 research outputs found

    Countering the Effects of Lead Bias in News Summarization via Multi-Stage Training and Auxiliary Losses

    Full text link
    Sentence position is a strong feature for news summarization, since the lead often (but not always) summarizes the key points of the article. In this paper, we show that recent neural systems excessively exploit this trend, which although powerful for many inputs, is also detrimental when summarizing documents where important content should be extracted from later parts of the article. We propose two techniques to make systems sensitive to the importance of content in different parts of the article. The first technique employs 'unbiased' data; i.e., randomly shuffled sentences of the source document, to pretrain the model. The second technique uses an auxiliary ROUGE-based loss that encourages the model to distribute importance scores throughout a document by mimicking sentence-level ROUGE scores on the training data. We show that these techniques significantly improve the performance of a competitive reinforcement learning based extractive system, with the auxiliary loss being more powerful than pretraining.Comment: 5 pages, accepted at EMNLP 201

    DOCK1 (Dedicator of cytokinesis 1)

    Get PDF
    Dedicator of cytokinesis (DOCK) is a family of proteins with 11 members in mammal which can regulate cell motility, phagocytosis, myoblast fusion, tumor suppression, neuronal polarization and adhesion. They are classified into four subfamilies A to D. Dock1 (Dock180), the founding member of the family, is a large protein which includes an N-terminal SH3 domain and a flanking helical bundle that are vital to the formation of a functioning complex Dock1-ELMO1 (Gumienny et al.,2001; Grimsley et al.,2004; Komander et al., 2008). Genetic and biochemical studies show that DOCK1 acts as a guanine-nucleotide exchange factor (GEF) for the small GTPase Rac1 (Diyokawa et al., 1998; Nolan et al., 1998). Rac1 is a small GTPase required for myoblast fusion in organisms such as fruit flies, zebrafish and mice (Rochlin et al., 1998). In addition to playing an important role in a broad spectrum of biological processes, numerous studies have demonstrated contributions of DOCK members to the development of cancer. Deciphering the detailed mechanisms by which DOCK proteins participate in tumorigenesis will shed light on the design of new treatment strategies

    Association of maternal levothyroxine use during pregnancy with offspring birth and neurodevelopmental outcomes: a population-based cohort study

    Get PDF
    BACKGROUND: The influence of maternal levothyroxine treatment during pregnancy remains unclear. This study aimed to evaluate the associations of maternal levothyroxine treatment during pregnancy with the birth and neurodevelopmental outcomes in offspring. METHODS: This population-based cohort study was conducted among pregnant women using the Hong Kong Clinical Data Analysis and Reporting System. Mother-child pairs in Hong Kong from 2001 to 2015 were included and children were followed up till 2020. We defined the exposure group as mothers who were exposed to levothyroxine during pregnancy. Preterm birth and small for gestational age (SGA) were included as birth outcomes. Attention-deficit/hyperactivity disorder (ADHD) and autism spectrum disorder (ASD) were included as neurodevelopmental outcomes. Odds ratios (OR) or hazard ratios (HRs) with a 95% confidence interval (CI) were evaluated to assess the association of gestational levothyroxine use with offspring birth and neurodevelopmental outcomes respectively, using propensity score fine-stratification weighting and a Cox proportional hazards regression model. RESULTS: Among 422,156 mother-child pairs, 2125 children were born from mothers exposed to levothyroxine during pregnancy. A significantly increased risk of preterm birth was observed in children with maternal levothyroxine exposure during pregnancy, when compared to mothers who had no history of thyroid-related diagnoses or prescriptions (weighted OR [wOR]: 1.22, 95% CI: 1.07, 1.39). Similarly, an increased risk of preterm birth was found among children of gestational levothyroxine users, when compared to children of mothers who had used levothyroxine before but stopped during pregnancy (wOR: 2.16, 95% CI: 1.09, 4.25). Sensitivity analysis, by excluding mothers exposed to psychotropic or antiepileptic medications before or during pregnancy, also indicated a similar increased risk of preterm birth regarding the gestational use of levothyroxine (wOR: 1.26, 95% CI: 1.10, 1.45). No significant association was observed for the risk of SGA, ADHD, and ASD. CONCLUSIONS: There is no evidence that gestational use of levothyroxine is associated with SGA, ADHD, or ASD in offspring. Gestational levothyroxine treatment is associated with a higher risk of preterm birth. Such risk might be confounded by the underlying maternal thyroid disease itself, however, we cannot completely exclude the possible effect of gestational L-T4 treatment on offspring preterm birth. Our findings provided support to the current guidelines on the cautious use of levothyroxine treatment during pregnancy. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12916-022-02586-9

    A Novel Cryo-controlled Growth Technique for High Performance Organometal Halide Perovskite Solar Cells

    Get PDF
    The recent trend of the high-performance perovskite solar cell (PSC) is based on multi-component perovskite materials. The reproducible perovskite growth techniques are crucial for acquiring mixed halide perovskite films with precise stoichiometry, desirable morphology, and low defect density

    Hypermethylation of SOX2 Promoter in Endometrial Carcinogenesis

    Get PDF
    This paper aimed at investigating the expression and methylation profiles of SOX2, a gene coding for the stem cell-related transcription factor SOX2, in endometrial carcinomas. By methylation-specific polymerase chain reaction (MS-PCR), the methylation status of SOX2 promoter region in 72 endometrial carcinomas and 12 normal endometrial samples was examined. Methylated allele was found in 37.5% (27/72) of endometrial carcinomas but only in 8.3% (1/12) of normal endometrial, significantly more frequent in cancers (P = .0472). SOX2 mRNA level was significantly reduced in endometrial carcinoma compared with nonneoplastic endometrium (P = .045). A significant correlation between SOX2 mRNA expression and hypermethylation of SOX2 was found (P = .024). Hypermethylation of SOX2 tended to be more frequently found in type II serous or clear cell adenocarcinoma. SOX2 methylation was also significantly correlated with shorter survival of patients (P = .046). In conclusion, epigenetic mechanisms may play a crucial role on the transcriptional regulation of SOX2 and loss of SOX2 expression may be related to endometrial carcinogenesis

    Wnt activation downregulates olfactomedin-1 in Fallopian tubal epithelial cells:a microenvironment predisposed to tubal ectopic pregnancy

    Get PDF
    Ectopic pregnancy (EP) occurs when the embryo fails to transit to the uterus and attach to the luminal epithelium of the Fallopian tube (FT). Tubal EP is a common gynecological emergency and more than 95% of EP occurs in the ampullary region of the FT. In humans, Wnt activation and downregulation of olfactomedin-1 (Olfm-1) occur in the receptive endometrium and coincided with embryo implantation in vivo. Whether similar molecular changes happen in the FT leading to EP remains unclear. We hypothesized that activation of Wnt signaling downregulates Olfm-1 expression predisposes to EP. We investigated the spatiotemporal expression of Olfm-1 in FT from non-pregnant women and women with EP, and used a novel trophoblastic spheroid (embryo surrogate)-FT epithelial cell co-culture model (JAr and OE-E6/E7 cells) to study the role of Olfm-1 on spheroid attachment. Olfm-1 mRNA expression in the ampullary region of non-pregnant FT was higher (P0.05) in the follicular phase than in the luteal phase. Ampullary tubal Olfm-1 expression was lower in FT from women with EP compared to normal controls at the luteal phase (histological scoring (H-SCORE)1.30.2 vs 2.40.5; P0.05). Treatment of OE-E6/E7 with recombinant Olfm-1 (0.2-5 g/ml) suppressed spheroid attachment to OE-E6/E7 cells, while activation of Wnt-signaling pathway by Wnt3a or LiCl reduced endogenous Olfm-1 expression and increased spheroid attachment. Conversely, suppression of Olfm-1 expression by RNAi increased spheroid attachment to OE-E6/E7 cells. Taken together, Wnt activation suppresses Olfm-1 expression, and this may predispose a favorable microenvironment of the retained embryo in the FT, leading to EP in humans. © 2012 USCAP, Inc All rights reserved.link_to_OA_fulltex

    Association of social isolation with health status among community-dwelling Chinese older adults living with homecare services: a cross-sectional survey in Hong Kong

    Get PDF
    BackgroundDefined as having few social relationships or infrequent social contact with family, friends, and the community, social isolation is a public health crisis. We aimed to evaluate the prevalence of social isolation and explore the association between social isolation and health status among community-dwelling Chinese Older Adults living with homecare services.MethodsThis is a cross-sectional survey with a structured questionnaire conducted among older adults aged ≥60 in the Central Kowloon District of Hong Kong during 2017–2018. Social isolation was assessed by the Lubben Social Network Scale-6 and a score less than 12 was defined as socially isolated. Six aspects of health status including fall risk, cognitive function, depression, activities of daily living (ADL), instrumental activities of daily living (IADL), and functional mobility were measured by standardized instruments. Multi-criteria decision analysis (MCDA) was applied to estimate an index to represent the overall health status of the respondents. Multivariate logistic/linear regression models were applied to examine the associations between social isolation and health status after adjusting the sociodemographic characteristics.ResultsAmong the 1,616 participants included in this analysis, the mean age was 80.9 years, 66.3% were female and 41.4% were identified as socially isolated. Compared with the non-isolated group, the socially isolated group had higher proportions of males, divorced or unmarried, ever smoking and drinking, living alone, and living in public housing without religion. After adjusting for confounders, the odds ratios (OR) comparing the socially isolated vs. non-isolated groups were 2.52 (95%CI: 1.79, 3.56) for high fall risk, 1.51 (1.17, 1.94) for cognitive impairment, and 1.78 (1.31, 2.43) for depression. The socially isolated group increased the odds of abnormal ADL, IADL, and functional mobility by 105–150%, and decreased the overall health score by 5.30 (3.42, 7.18).ConclusionWe demonstrated the association of social isolation with poorer physical function and mental health and overall health status among the community-dwelling Chinese older adults living with homecare services. These findings provided new knowledge about the association of social isolation with both physical and mental function for daily living even for those receiving an integrated homecare service in the community. It implies that an unmet healthcare need existed when comparing the service scope of the current homecare services in the community. It also highlighted the need for targeted prevention and intervention initiatives among community-dwelling old adults to alleviate social isolation for better health and good functioning in the community
    corecore