321 research outputs found

    Research on Online Word-of-mouth Sentiment Analysis and Attribute Extraction Based on Deep Learning

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    Online word-of-mouth content mining is of great significance to product, service improvement and demand prediction of online marketing enterprises. However, most studies have focused on the identification of the sentiment tendency of online word-of-mouth, and lack of text content mining for online word-of-mouth, especially negative word-of-mouth. This paper introduces deep learning into online word-of-mouth sentiment tendency analysis and negative word-of-mouth word attribute feature extraction, and builds an online word-of-mouth sentiment tendency analysis and attribute extraction model based on LSTM deep learning algorithm. The model was trained and tested through online word-of-mouth data of a fashion apparel e-commerce company. The results show that the LSTM model has a good effect on sentiment analysis and negative word-of-mouth attribute feature extraction. Through comparative experiments, it is shown that the model has a better effect than the traditional machine learning methods (SVM, Naive Bayes) in the analysis of sentiment tendency

    Influence of Fatty Acids and their Derivatives on Aphid Resistance in Arabidopsis and Tomato

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    Fatty acid desaturases (FADs) are enzymes that act in the chloroplast or the endoplasmic reticulum (ER) to incorporate double bonds into the acyl chains of fatty acids, and recent evidence indicates that at least one of these enzymes, FAD7, also influences plant resistance to aphids. FAD7 is an enzyme in the chloroplast that is found throughout the plant kingdom and that desaturates 16- and 18-carbon fatty acids (FAs) with two double bonds (dienoic acids) to generate FAs with three double bonds (trienoic acids). In tomato (Solanum lycopersicum) and the model plant Arabidopsis thaliana, mutants with impaired FAD7 function are more resistant to aphids than wild-type controls. Compared to wild-type plants, these mutants have increased 18-carbon FAs with one double bond (C18:1), higher 16- and 18-carbon FAs with two double bonds (C16:2 and C18:2), and lower 16- and 18-carbon FAs with three double bonds (C16:3 and C18:3). These changes in FA composition are most pronounced in galactolipids which are abundant in the chloroplast, but loss of function of FAD7 also has a modest effect on phospholipids from the endoplasmic reticulum (ER). In addition, loss of function of FAD7 also influences foliar profiles of C6 volatiles, a class of FA derivatives that have previously been reported to contribute to aphid resistance in potato and other plant species. The goal of this project was to investigate which of these changes in fatty acid metabolism contribute to aphid resistance in Arabidopsis and tomato mutants with impaired FAD7 activity. To this end, we compared aphid performance on a panel of mutant plant lines with variation in FA composition or C6 volatile production. Our results suggested that aphid resistance in plants with impaired FAD7 activity is independent of C6 volatile synthesis, because 1) the aphid-resistant fad7 mutant in Arabidopsis also carries a mutation in the hydroperoxide lyase (HPL) gene, which is required for C6 volatile synthesis; and 2) suppressing expression of HPL in a FAD7-impaired tomato line did not compromise aphid resistance in this line. Analysis of aphid resistance and FA profiles in a panel of Arabidopsis mutants with impairments in different FADs also indicated that aphid resistance was impacted by FAD activity in the ER as well as in the chloroplast. This suggested that C18 rather than C16 FAs plays a determining role in aphid resistance, since C16 FAs are exclusively synthesized in the chloroplast whereas C18 FAs are produced in both subcellular compartments. Furthermore, resistance appeared to be associated with high C18:2 levels, because mutant lines with high C18:2 displayed resistance to aphids, but other lines with low C18:2 were susceptible even if they had high C18:1 and low C18:3 levels. Potentially, C18:2 or its derivatives could contribute to defensive signaling or synthesis of defensive metabolites to combat aphid infestations. This study aids in identifying new sources of plant resistance to aphids, and advances our understanding of how FA metabolism modulates plant defenses against insects

    A novel isoprene synthase from the monocot tree Copernicia prunifera (Arecaceae) confers enhanced drought tolerance in transgenic Arabidopsis

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    The capacity to emit isoprene, among other stresses, protects plants from drought, but the molecular mechanisms underlying this trait are only partly understood. The Arecaceae (palms) constitute a very interesting model system to test the involvement of isoprene in enhancing drought tolerance, as their high isoprene emissions may have contributed to make them hyperdominant in neotropical dry forests, characterized by recurrent and extended periods of drought stress. In this study we isolated and functionally characterized a novel isoprene synthase, the gene responsible for isoprene biosynthesis, from Copernicia prunifera, a palm from seasonally dry tropical forests. When overexpressed in the non-emitter Arabidopsis thaliana, CprISPS conferred significant levels of isoprene emission, together with enhanced tolerance to water limitation throughout plant growth and development, from germination to maturity. CprISPS overexpressors displayed higher germination, cotyledon/leaf greening, water usage efficiency, and survival than WT Arabidopsis under various types of water limitation. This increased drought tolerance was accompanied by a marked transcriptional up-regulation of both ABA-dependent and ABA-independent key drought response genes. Taken together, these results demonstrate the capacity of CprISPS to enhance drought tolerance in Arabidopsis and suggest that isoprene emission could have evolved in Arecaceae as an adaptive mechanism against drough

    Critical Periods of Perturbations of Reversible Rigidly Isochronous Centers

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    We study the problem of bifurcation of critical periods of a time-reversible polynomial system of degree n. We first present a new method to find the number of zeros of the period function. Then applying our results, we study the number of critical periods for some polynomial systems and obtain new results

    A novel frame-shift mutation in FRMD7 causes X-linked idiopathic congenital nystagmus in a Chinese family

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    Purpose: To screen mutations in the FERM domain-containing 7 (FRMD7) gene in a Chinese family with X-linked idiopathic congenital nystagmus (ICN). Methods: It has been reported that FRMD7 mutations account for approximately 47% of X-linked nystagmus in Chinese patients. We collected 5 ml of blood samples from members of a family with X-linked ICN and 100 normal controls. Mutations in FRMD7 were determined by sequencing PCR products. Results: We identified a previously unreported 4 bp deletion in FRMD7 (c.1486-1489 del TTTT) in a Chinese family. The mutation co-segregated with the disease phenotype in patients and female carriers, while it was not detected in other relatives or in the 100 normal controls. Conclusions: Our results expand the spectrum of FRMD7 mutations causing ICN, and further confirm the role of FRMD7 in the pathogenesis of ICN. Direct sequencing of FRMD7 could be used as a diagnostic testing of idiopathic congenital nystagmus.Biochemistry & Molecular BiologyOphthalmologySCI(E)PubMed4ARTICLE297-992765-27681

    A new novel mutation in FBN1 causes autosomal dominant Marfan syndrome in a Chinese family

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    Purpose: Screening of mutations in the fibrillin-1 (FBN1) gene in a Chinese family with autosomal dominant Marfan syndrome (MFS). Methods: It has been reported that FBN1 mutations account for approximately 90% of Autosomal Dominant MFS. FBN1 mutations were analyzed in a Chinese family of 36 members including 13 MFS patients. The genomic DNAs from blood leukocytes of the patients and their relatives were isolated and the entire coding region of FBN1 was amplified by PCR. The sequence of FBN1 was dertermined with an ABI 3100 Genetic Analyzer. Results: A previously unreported the missense mutation G214S (caused by a 640 A -> G heterozygous change) in FBN1 was identified in the Chinese family. The mutation was associated with the disease phenotype in patients, but not detected in their relatives or in the 100 normal controls. Conclusions: This is the first report of molecular characterization of FBN1 in the MFS family of Chinese origin. Our results expand the spectrum of FBN1 mutations causing MFS and further confirm the role of FBN1 in the pathogenesis of MFS. Direct sequencing of the mutation in FBN1 may be used for diagnosis of MFS.http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcApp=PARTNER_APP&SrcAuth=LinksAMR&KeyUT=WOS:000301238300001&DestLinkType=FullRecord&DestApp=ALL_WOS&UsrCustomerID=8e1609b174ce4e31116a60747a720701Biochemistry & Molecular BiologyOphthalmologySCI(E)PubMed10ARTICLE10-1181-861

    Chronic Alcohol Causes Alteration of Lipidome Profiling in Brain

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    Much efforts have been tried to clarify the molecular mechanism of alcohol-induced brain damage from the perspective of genome and protein; however, the effect of chronic alcohol exposure on global lipid profiling of brain is unclear. In the present study, by using Q-TOF/MS-based lipidomics approach, we investigated the comprehensive lipidome profiling of brain from the rats orally administrated with alcohol daily, continuously for one year. Through systematically analysis of all lipids in prefrontal cortex (PFC) and striatum region, we found that long-term alcohol exposure profoundly modified brain lipidome profiling. Notably, three kinds of lipid classes, glycerophospholipid (GP), glycerolipid (GL) and fatty acyls (FA), were significantly increased in these two brain regions. Interestingly, most of the modified lipids were involved in synthetic pathways of endoplasmic reticulum (ER), which may result in ER stress-related metabolic disruption. Moreover, alcohol-modified lipid species displayed long length of carbon chain with high degree of unsaturation. Taken together, our results firstly present that chronic alcohol exposure markedly modifies brain lipidomic profiling, which may activate ER stress and eventually result in neurotoxicity. These findings provide a new insight into the mechanism of alcohol-related brain damage.Peer reviewe

    Inhibition and Production of Anger Cost More: Evidence From an ERP Study on the Production and Switch of Voluntary Facial Emotional Expression

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    Humans need to flexibly produce or switch different facial emotional expressions to meet social communication need. However, little is known about the control of voluntary facial emotional expression. We investigated the production and switch of facial expressions of happiness and anger in a response-priming task of 23 Chinese female university students and recorded electroencephalographic (EEG) signals. Results revealed that a frontal-central P2 component demonstrated greater positivity in the invalidly cued condition compared with the validly cued condition. Comparing the two facial emotional expressions, data from the contingent negative variation (CNV) component revealed that happiness and anger did not differ in the motor preparation phase. While data from N2 and P3 showed that switching from anger to happiness elicited larger N2 amplitudes than switching from happiness to anger and switching from happiness to anger elicited larger P3 than switching from anger to happiness. The results revealed that in invalidly cued condition, the inhibition (N2) and reprogramming (P3) cost of anger was greater than that of happiness. The findings indicated that during the switching process, both the inhibition and the reprogramming of anger cost more processing resources than those of happiness

    Hospitality brand management by a score-based q-rung ortho pair fuzzy V.I.K.O.R. method integrated with the best worst method

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    Hospitality brand management is a primary concern in the hotel industry and the evaluation of brands can be considered as a decision-making problem with multiple criteria. The evaluation information of brands may be uncertain sometimes. The q-rung orthopair fuzzy set (q-R.O.F.S.), which represents the preference degree of a person from the positive and negative aspects, has turned out to be an efficient tool in depicting uncertainty and vagueness in the decision-making process. This article dedicates to presenting an integrated multiple criteria decision-making method with q-R.O.F.S.. Firstly, a score function of the q-R.O.F.S. is proposed to solve the deficiencies of two existing score functions. Then, a weight-determining method based on the additive consistency of the preference relation is developed. A decision-making method integrating the score function, the best worst method and the VIsekriterijumska optimizacija I KOmpromisno Resenje (V.I.K.O.R.) which means multiple criteria compromise optimisation in English) method is further proposed. Finally, a case study regarding the hospitality brand management is provided to show the applicability and validity of the proposed method

    Repeat hepatectomy for recurrent hepatocellular carcinoma: a local experience and a systematic review

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    Background: This study aimed to assess the efficacy and safety of repeat hepatectomy for recurrent hepatocellular carcinoma (HCC). Methods: Thirty-seven patients who underwent a curative repeat hepatectomy in our hospital were retrospectively studied. An extensive database literature search was performed to obtain for all relevant studies. Results: In our series, there were no perioperative deaths during repeat hepatectomy for recurrent HCC. Patients survival after repeat hepatectomy were similar to 429 patients undergoing initial hepatectomy. A computerized search of the Medline and PubMed databases found 29 retrospective studies providing relevant data in 1149 patients were included for appraisal and data extraction. After the repeat hepatectomy, postoperative morbidity ranged from 6.2% to 68.2% with a median per cohort of 23.5 per cent. There were 7 perioperative deaths (0.7 per cent of 993 for whom mortality data were provided). The overall median survival ranged from 21 to 61.5 months, with 1 -, 3 -, and 5-year survival of 69.0% to 100%, 21.0% to 87.0%, and 25.0% to 87.0%, respectively. Conclusions: Repeat hepatectomy can be performed safely and is associated with long-term survival in a subset of patients with recurrent HCC. However, the findings have to be carefully interpreted due to the lower level of evidence. A randomized controlled study is needed to compare repeat hepatectomy and other modalities for recurrent HCC
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