30 research outputs found

    Packing and Padding: Coupled Multi-index for Accurate Image Retrieval

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    In Bag-of-Words (BoW) based image retrieval, the SIFT visual word has a low discriminative power, so false positive matches occur prevalently. Apart from the information loss during quantization, another cause is that the SIFT feature only describes the local gradient distribution. To address this problem, this paper proposes a coupled Multi-Index (c-MI) framework to perform feature fusion at indexing level. Basically, complementary features are coupled into a multi-dimensional inverted index. Each dimension of c-MI corresponds to one kind of feature, and the retrieval process votes for images similar in both SIFT and other feature spaces. Specifically, we exploit the fusion of local color feature into c-MI. While the precision of visual match is greatly enhanced, we adopt Multiple Assignment to improve recall. The joint cooperation of SIFT and color features significantly reduces the impact of false positive matches. Extensive experiments on several benchmark datasets demonstrate that c-MI improves the retrieval accuracy significantly, while consuming only half of the query time compared to the baseline. Importantly, we show that c-MI is well complementary to many prior techniques. Assembling these methods, we have obtained an mAP of 85.8% and N-S score of 3.85 on Holidays and Ukbench datasets, respectively, which compare favorably with the state-of-the-arts.Comment: 8 pages, 7 figures, 6 tables. Accepted to CVPR 201

    To Disclose or Not to Disclose, That Is the Question: Evidence from TripAdvisor

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    Online consumers may be hesitant to disclose personal information due to potential threats, leading to an impact on their content generation. This, in turn, poses a challenge to the credibility and sustainability of online reviews on digital platforms. To address this issue, our research examines how consumers\u27 self-disclosure affects their rating behaviors and the existence of the positive-negative asymmetry based on negativity bias. Utilizing data from TripAdvisor, our analysis demonstrated that consumers\u27 self-disclosure had a negative impact on rating inconsistency and a stronger herding behavior for those submitting ratings lower than the hotel’s average ratings. Additionally, we found that certain factors, such as more peer disclosure, longer time intervals between check-in and review posting, and greater expertise, can mitigate the negative impact of self-disclosure on rating behavior. Our findings make critical contributions to the extant literature, as well as provide significant managerial implications to participants in the digital platform

    Survival Advantage of Both Human Hepatocyte Xenografts and Genome-Edited Hepatocytes for Treatment of α-1 Antitrypsin Deficiency.

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    Hepatocytes represent an important target for gene therapy and editing of single-gene disorders. In α-1 antitrypsin (AAT) deficiency, one missense mutation results in impaired secretion of AAT. In most patients, lung damage occurs due to a lack of AAT-mediated protection of lung elastin from neutrophil elastase. In some patients, accumulation of misfolded PiZ mutant AAT protein triggers hepatocyte injury, leading to inflammation and cirrhosis. We hypothesized that correcting the Z mutant defect in hepatocytes would confer a selective advantage for repopulation of hepatocytes within an intact liver. A human PiZ allele was crossed onto an immune-deficient (NSG) strain to create a recipient strain (NSG-PiZ) for human hepatocyte xenotransplantation. Results indicate that NSG-PiZ recipients support heightened engraftment of normal human primary hepatocytes as compared with NSG recipients. This model can therefore be used to test hepatocyte cell therapies for AATD, but more broadly it serves as a simple, highly reproducible liver xenograft model. Finally, a promoterless adeno-associated virus (AAV) vector, expressing a wild-type AAT and a synthetic miRNA to silence the endogenous allele, was integrated into the albumin locus. This gene-editing approach leads to a selective advantage of edited hepatocytes, by silencing the mutant protein and augmenting normal AAT production, and improvement of the liver pathology. Mol Ther 2017 Nov 1; 25(11):2477-2489

    Survival Advantage of Both Human Hepatocyte Xenografts and Genome-Edited Hepatocytes for Treatment of alpha-1 Antitrypsin Deficiency

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    Hepatocytes represent an important target for gene therapy and editing of single-gene disorders. In alpha-1 antitrypsin (AAT) deficiency, one missense mutation results in impaired secretion of AAT. In most patients, lung damage occurs due to a lack of AAT-mediated protection of lung elastin from neutrophil elastase. In some patients, accumulation of misfolded PiZ mutant AAT protein triggers hepatocyte injury, leading to inflammation and cirrhosis. We hypothesized that correcting the Z mutant defect in hepatocytes would confer a selective advantage for repopulation of hepatocytes within an intact liver. A human PiZ allele was crossed onto an immune-deficient (NSG) strain to create a recipient strain (NSG-PiZ) for human hepatocyte xenotransplantation. Results indicate that NSG-PiZ recipients support heightened engraftment of normal human primary hepatocytes as compared with NSG recipients. This model can therefore be used to test hepatocyte cell therapies for AATD, but more broadly it serves as a simple, highly reproducible liver xenograft model. Finally, a promoterless adeno-associated virus (AAV) vector, expressing a wild-type AAT and a synthetic miRNA to silence the endogenous allele, was integrated into the albumin locus. This gene-editing approach leads to a selective advantage of edited hepatocytes, by silencing the mutant protein and augmenting normal AAT production, and improvement of the liver pathology

    N6-methyladenosine RNA modification promotes viral genomic RNA stability and infection

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    Molecular manipulation of susceptibility (S) genes that are antipodes to resistance (R) genes has been adopted as an alternative strategy for controlling crop diseases. Here, we show the S gene encoding Triticum aestivum m(6)A methyltransferase B (TaMTB) is identified by a genome-wide association study and subsequently shown to be a positive regulator for wheat yellow mosaic virus (WYMV) infection. TaMTB is localized in the nucleus, is translocated into the cytoplasmic aggregates by binding to WYMV NIb to upregulate the m(6)A level of WYMV RNA1 and stabilize the viral RNA, thus promoting viral infection. A natural mutant allele TaMTB-SNP176C is found to confer an enhanced susceptibility to WYMV infection through genetic variation analysis on 243 wheat varieties. Our discovery highlights this allele can be a useful target for the molecular wheat breeding in the future

    SNIPPET-BASED UNSUPERVISED APPROACH FOR SENTIMENT CLASSIFICATION OF CHINESE ONLINE REVIEWS

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    Sentiment classification seeks to identify general attitude of a piece of text of comments or reviews on certain subject, be it positive or negative. Most existing researches on sentiment classification employ supervised learning approaches that rely on annotated data. However, sentiment is expressed differently on different subjects in different domains, and having annotated corpora for every domain of interest is not always practical. This paper proposes an unsupervised learning approach for classifying text of online reviews as recommended or not recommended. The proposed method is based on search engine snippet, summary information on the result page of a search engine. A basic assumption is that terms with similar orientation tend to co-occur. The co-occurrence is measured by utilizing snippets returned from search engines, with a query consisting of the text and a seed positive or negative word. With the information of snippets, the proposed method may estimate the association of candidate terms more accurately. This allows us to reliably predict the sentiment orientation of customer reviews. Texts of customer reviews are then classified as recommended or not recommended if the average sentiment orientations of its phrases are positive or negative. The research data set of this study consists of 600 Chinese online reviews about travel destinations retrieved from Ctrip.com. Our approach achieves an accuracy of 76.5%. Factors that influence the accuracy of the sentiment classification of Chinese online reviews were discussed.Sentiment classification, unsupervised learning approach, snippet, online review, chinese

    Alkaline metal doped strontium cobalt ferrite perovskites as cathodes for intermediate-temperature solid oxide fuel cells

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    Perovskite oxides SrKFeCoO (SKFCx, x = 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0) are investigated as potential cathode materials for intermediate-temperature solid oxide fuel cells (IT-SOFCs) on SmCeO (SDC) electrolyte. The cubic phase of the SKFCx oxides is demonstrated by x-ray diffraction. The SKFCx cathode shows good compatibility with the SDC electrolyte up to 900 °C. Among the investigated compositions, SKFC0.1 displays the highest electrical conductivity of 443–146 S·cm from 350 °C to 800 °C in flow air. The area specific resistances (ASRs) of the SKFCx (x = 0.1, 0.3, 0.5, 0.7, 0.9 and 1.0) cathodes are 0.047, 0.058, 0.066, 0.101, 0.155 and 0.175 Ω cm at 650 °C in air on an SDC electrolyte. Among the five tested cathodes, SKFC0.1 exhibits the lowest area specific resistances between 550 °C and 750 °C, when tested on its symmetric cell configuration of cathode|SDC|cathode. The thermally stabilized cubic perovskite structure of the SKFC0.1 powder is demonstrated by high-temperature XRD. The average linear thermal expansion coefficient α of SKFC0.1 is 18.9×10 K. A peak power density of 1643 mW·cm is achieved on SKFC0.1|SDC|Ni-SDC anode supported fuel cell at 650 °C. These features, and excellent electrocatalytic activity and good stability, indicate the potential of alkaline metal doped strontium cobalt ferrite perovskites are promising cathode materials for IT-SOFCs

    Modulation of Gut Microbiome Composition and Function in Experimental Colitis Treated with Sulfasalazine

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    Inflammatory bowel disease (IBD) results from alterations in intestinal flora and the immune system. Sulfasalazine (SASP) is a sulfa antimicrobial used to treat IBD in clinic for years. However, how SASP affects gut microbes and its potential functions remains unclear. To investigate the relationships of SASP, IBD, and gut microbiome, we used 2,4,6-trinitrobenzenesulfonic acid (TNBS) to induce experimental colitis in rats, and analyzed the microbiota in the fecal samples, which come from the control group (treated with ethanol + saline), the model group (treated with TNBS-ethanol + saline) and the SASP group (treated with TNBS-ethanol + SASP), with 16S gene sequencing and followed up a subset sample using shotgun sequencing. The study found that SASP treatment could not only restore the TNBS-induced gut dysbiosis, which was proved by the increasing amount of SCFAs-producing bacteria and lactic acid-producing bacteria as well as the decreasing amount of Proteobacteria, but also modulate the dysregulated function of the TNBS-induced colitis to resemble that of the control group, including an increased capacity for basic metabolism (carbohydrate metabolism, citrate cycle) and a decrease in the oxidative stress (riboflavin, sulfur, cysteine) as well as bacterial pathogenesis (cell motility and secretion, bacterial motility proteins, flagellar assembly). Moreover, a higher proportion of Mycoplasma was observed in the SASP group, which may associate with infertility. In all, the study provides insight into specific microbial clades and pathways linked with SASP treatment to elaborate the mechanism for treatment of IBD

    Additional file 1 of Association of changes in frailty status with the risk of all-cause mortality and cardiovascular death in older people: results from the Chinese Longitudinal Healthy Longevity Survey (CLHLS)

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    Additional file 1: eFigure 1. Stratified analyses by potential modifiers of the association between changes in frailty status and risk of all-cause mortality
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