Comparative Evaluation of Sentiment Analysis Methods Across Arabic Dialects

Sentiment analysis in Arabic is challenging due to the complex morphology of the language. The task becomes more challenging when considering Twitter data that contain significant amounts of noise such as the use of Arabizi, code-switching and different dialects that varies significantly across the Arab world, the use of non-Textual objects to express sentiments, and the frequent occurrence of misspellings and grammatical mistakes. Modeling sentiment in Twitter should become easier when we understand the characteristics of Twitter data and how its usage varies from one Arab region to another. We describe our effort to create the first Multi-Dialect Arabic Sentiment Twitter Dataset (MD-ArSenTD) that is composed of tweets collected from 12 Arab countries, annotated for sentiment and dialect. We use this dataset to analyze tweets collected from Egypt and the United Arab Emirates (UAE), with the aim of discovering distinctive features that may facilitate sentiment analysis. We also perform a comparative evaluation of different sentiment models on Egyptian and UAE tweets. These models are based on feature engineering and deep learning, and have already achieved state-of-The-Art accuracies in English sentiment analysis. Results indicate the superior performance of deep learning models, the importance of morphological features in Arabic NLP, and that handling dialectal Arabic leads to different outcomes depending on the country from which the tweets are collected.This work was made possible by NPRP 6-716-1-138 grant from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.Scopu

Fonctions des facteurs bHLH, TAL-1 et LYL dans les cellules endothéliales (Recherche de gènes cibles)

L'angiogenèse est constituée de plusieurs étapes de migration, proliferation et morphogenèse. Ces étapes sont controllées par plusieurs facteurs de transcription comme deux facteurs apparentés de la famille bHLH TAL-1 et LYL. TAL-1 est associé à l'angiogenèse active alors que LYL est responsable du maintien de la quiescence des tissus. Pour comprendre leur mode de fonctionnement, une étude du transcriptome réalisée en aval de ces facteurs dans les cellules endothéliales révèle de plusieurs gènes modulés par ces deux facteurs et qui ont des fonctions majeurs durant l'angiogenèse : VE-cadh, ANG2, MMP10 et inhibiteur de la différenciation. On a démontré que la VE-cad, constituant majeur des jonctions adhérentes endothéliales, est le premier cible de TAL-1 et ses cofacteurs E47, LMO2, GATA2 et LDB1. Le deuxième gène sélectionné, ANG2, joue un rôle majeur dans la lignée endothéliale. L'étude de ce gène montre qu'il est directement contrôlé par TAL-1 et ses cofacteurs. Des études doivent être réalisées sur les autres gènes régulés pour essayer de trouver des cibles de TAL-1 et de LYLAngiogenesis consists of several steps of migration, proliferation and morphogenesis. This series of events is controlled by several transcription factors like TAL-1 and LYL which are two related factors belonging to the bHLH family. Whereas TAL-1 is associated with active angiogenesis, the expression of LYL on the contrary is upregulated in quiescent tissues. To understand their respective functions, we performed transcriptome analysis downstream these two factors in endothelial cells, revealed several genes that are modulated by both factors and known to have important functions in angiogenesis: VE-cadh, ANG2, MMP10 and Inhibitor of differentiation-1. We demonstrated that the gene encoding VE-cadh, the major component of endothelial adherens junction, is the first target of TAL-1 in endothelial cells and its cofactors E47, LMO2, GATA2 and LDB1. The second selected gene, ANG2, plays a major role in the endothelial lineage. The study of this gene show that it is also directly controlled by TAL-1 and its co-factors.Studies will be done on other regulated genes to find other targets of TAL-1 and LYLMONTPELLIER-BU Sciences (341722106) / SudocSudocFranceF

A Characterization Study of Arabic Twitter Data with a Benchmarking for State-of-the-Art Opinion Mining Models

Opinion mining in Arabic is a challenging task given the rich morphology of the language. The task becomes more challenging when it is applied to Twitter data, which contains additional sources of noise, such as the use of unstandardized dialectal variations, the non-conformation to grammatical rules, the use of Arabizi and code-switching, and the use of non-text objects such as images and URLs to express opinion. In this paper, we perform an analytical study to observe how such linguistic phenomena vary across different Arab regions. This study of Arabic Twitter characterization aims at providing better understanding of Arabic Tweets, and fostering advanced research on the topic. Furthermore, we explore the performance of the two schools of machine learning on Arabic Twitter, namely the feature engineering approach and the deep learning approach. We consider models that have achieved state-of-the-art performance for opinion mining in English. Results highlight the advantages of using deep learning-based models, and confirm the importance of using morphological abstractions to address Arabic's complex morphology. 2017 Association for Computational LinguisticsThis work was made possible by NPRP 6-716-1-138 grant from the Qatar National Research Fund (a member of Qatar Foundation). The statements made herein are solely the responsibility of the authors.Scopu

Child injuries in Lebanon: assessing mothers’ injury prevention knowledge attitude and practices

Abstract Background Childhood injury is a neglected public health problem with a sizeable burden on children’s well-being and their families. This study aims to describe the pattern and types of childhood injuries and to determine the level of mothers’ Knowledge, Attitude, and Practices (KAP) towards childhood injury prevention in Lebanon. The study further examines the association between childhood injury occurrence and mothers’ supervision. Methods This cross-sectional study recruited mothers of children aged up to 10 years from multiple sites (i.e., a medical center, a private clinic, a healthcare facility, and a refugee camp clinic). Data were collected on mothers’ KAP toward childhood injuries using self-administrated questionnaires. A summation score for KAP correct answers was calculated and descriptive and statistical analyses were performed to measure the association between the outcomes. Results A total of 264 mothers were surveyed and injury data were collected on their 464 children. The prevalence of childhood injury was 20% in the past 12 months, mostly sustained by males (53.8%) and children aged 5–10 years (38.7%). The most common type of injury was fall (48.4%), followed by burns (%7.5), and sports injuries (7.5%). Hospitalized children were more likely to be males and older than 5 years (p < 0.001). More than one-third of the mothers demonstrated poor knowledge, while the majority showed poor practice (54.4%), and fair attitude (45.6%) towards child injury prevention. Children of working mothers have three times higher odds of sustaining injuries (OR: 2.95, 95% CI: 1.60;5.47) compared to those of non-working mothers, accounting for possible confounders (p = 0.001). Conclusion Childhood injuries represent a major health problem in Lebanon. Findings from this study showed that mothers are less knowledgeable and unprepared to prevent their children from getting injured. Educational programs are much needed to address the gap in the mothers' KAP toward child injury prevention. Further studies are recommended to understand the cultural context and examine its key determinants to identify effective strategies and develop tailored interventions for preventing childhood injuries

TAL-1/SCL and Its Partners E47 and LMO2 Up-Regulate VE-Cadherin Expression in Endothelial Cells▿ †

The basic helix-loop-helix TAL-1/SCL essential for hematopoietic development is also required during vascular development for embryonic angiogenesis. We reported that TAL-1 acts positively on postnatal angiogenesis by stimulating endothelial morphogenesis. Here, we investigated the functional consequences of TAL-1 silencing in human primary endothelial cells. We found that TAL-1 knockdown caused the inhibition of in vitro tubulomorphogenesis, which was associated with a dramatic reduction in vascular endothelial cadherin (VE-cadherin) at intercellular junctions. Consistently, silencing of TAL-1 as well as of its cofactors E47 and LMO2 down-regulated VE-cadherin at both the mRNA and the protein level. Endogenous VE-cadherin transcription could be activated in nonendothelial HEK-293 cells by the sole concomitant ectopic expression of TAL-1, E47, and LMO2. Transient transfections in human primary endothelial cells derived from umbilical vein (HUVECs) demonstrated that VE-cadherin promoter activity was dependent on the integrity of a specialized E-box associated with a GATA motif and was maximal with the coexpression of the different components of the TAL-1 complex. Finally, chromatin immunoprecipitation assays showed that TAL-1 and its cofactors occupied the VE-cadherin promoter in HUVECs. Together, these data identify VE-cadherin as a bona fide target gene of the TAL-1 complex in the endothelial lineage, providing a first clue to TAL-1 function in angiogenesis

TAL1- and/or LYL1-containing complexes activate endogenous <i>ANG-2</i> transcription.

<p>Endothelial HMEC-1 cells or epithelial 293T cells were transfected with the indicated combination of expression plasmids along with pEGFP to control transfection efficiency; GFP-positive cells monitored by FACS analysis varied from 60 to 80% of total living cells. Total RNA and whole cell extracts (WCL) were prepared 48 h post-transfection for gene expression analysis. (A) <i>ANG2</i> mRNA expression was analyzed by RT-qPCR. The signals of mRNAs were normalized to those of <i>GAPDH</i>. Results are expressed as <i>ANG-2</i> mRNA levels relative to those of cells transfected with empty vector set at 1 (dotted line). Results are shown as the means ± SD of at least three separate experiments. Asterisks show significant differences with mRNA levels from cells transfected with empty vector. *or ^#, <i>P</i><0.05; ** or ^##, <i>P</i><0.01; ***, <i>P</i><0.001. (B) WCL (10 µg) from the indicated transfected cells were analysed by immunoblot to control ectopic protein expression using the appropriate antibodies. Shown images are representative of a typical experiment; vertical lines indicate the suppression of non-informative lanes from a unique blot.</p

TAL1, LYL1, LMO2 and GATA2 bind the <i>ANG-2</i> promoter proximal region.

<p>(<b>A</b>) Alignment of the nucleotide sequence of proximal region of human (top line) and mouse <i>ANG-2</i> promoter. The conserved E-box, GATA-binding sites and GC-box boxes are indicated. The TATA box is underlined. +1 indicates the transcription start site. Of note, the E box⁻⁶⁴ is separated by 11 nucleotides from both the upstream GC-box⁻⁸⁵ and the downstream GATA⁻⁴⁷. (<b>B</b>) The indicated endothelial cells were transfected with either the wild-type −412/+73 <i>ANG-2</i> reporter construct (black bars) or the mutated Ebox⁻⁶⁴ construct (grey bars). Data are shown relative to the luciferase activity of wt construct (set at 100%) for each cell type. Bars are the means +/− S.D. of three independent experiments, each performed in triplicate. **, <i>P</i><0.01; *, <i>P</i><0.05. (<b>C</b>) <u>Chromatin immunoprecipitation assays.</u> Chromatin immunoprecipitations assays (ChIP) were performed on cross-linked chromatin from LLyECs using the indicated antibody. To control chromatin quality, ChIP assays were performed using an antibody against acetylated histone H3. Aliquots of immunoprecipitated DNAs were amplified by PCR with primers (arrows) targeting the proximal <i>ANG-2</i> promoter (−165; +76) or a non-transcribed genomic region upstream of the <i>c-KIT</i> gene used as a negative control. PCR products were analyzed by gel electrophoresis. <u>Top:</u> Schematic location of conserved elements within the human <i>ANG-2</i> promoter: G: GATA-binding site; GC: GC-box; E: E-box. Shown images are representative of one of three independent experiments. <u>Bottom</u>: Fold-enrichment of target genomic regions immunoprecipitated by each antibody was normalized to the levels obtained with control IgGs, which was assigned a value of 1, and plotted as the increase over the levels of enrichment at the negative control region. The error bars represent +/− S.D. from three independent ChIPs. **, <i>P</i><0.01; *, <i>P</i><0.05.</p

Analysis of TAL1, LYL1 and LMO2 interactions in cells.

<p>293T cells were cotransfected with the indicated expression vectors along with eGFP-expressing vector to control transfection efficacy. (<b>A</b>) <u>TAL1 and LYL1 interactions</u>: Equal amounts of whole cell lysates (WCL) were immunoprecipitated with the indicated antibody. Mouse α-Flag- mAb was used to precipitate Flag-LYL1. Input shows levels of tested proteins in untreated WCL (10 µg per lane). Input and immunoprecipitated proteins were analyzed by immunoblot using the appropriate antibodies. (<b>B</b>) <u>E47 induces TAL1 hyperphosphorylation:</u> WCL from cells transfected with combination a or b (indicated in A) were immunoprecipitated with mouse α-TAL1 mAb. Immunoprecipitates coupled to sepharose were treated by Calf Intestinal alcaline Phosphatase (CIP) and analyzed by immunoblot using goat α-TAL1 pAb. (<b>C</b>) <u>LMO2 interactions:</u> Equal amounts of WCL were treated with mouse α-HA-mAb coupled to agarose to precipitate HA-LMO2. Input shows levels of tested proteins in untreated WCL (10 µg per lane). Input and immunoprecipitated proteins were analyzed by immunoblot using the appropriate antibodies.</p

LYL1 is able to form homodimers <i>in vitro</i> and <i>in vivo</i>.

<p>(<b>A</b>) <u>GST pull-down assays</u>: ³⁵S-labeled TAL1 and LYL1 proteins produced <i>in vitro</i> by coupled transcription-translation were incubated with the indicated GST protein coupled to glutathione-Sepharose beads. Captured radiolabeled proteins were analyzed by SDS-PAGE and visualized by autoradiography. (<b>B</b>) <u>LYL1 forms homodimers in cells</u>: 293T cells were transfected with Flag-LYL1 and/or HA-LYL1. Equal amounts of WCL were immunoprecipitated with α-Flag- and α-HA-antibodies to precipitate LYL1-Flag and LYL1-HA respectively. Input shows levels of tested proteins in untreated WCL (10 µg per lane). Input and immunoprecipitated proteins were analyzed by immunoblot using the indicated antibody.</p

TAL1-, LYL1- or LMO2-silencing down regulates <i>ANG-2</i> expression.

<p>(<b>A, C</b>) HUVECs were transfected with siRNAs targeting <i>TAL1</i>, <i>LYL1</i>, <i>LMO2</i> or <i>eGFP</i> (used as the control). Whole cell extracts and total RNAs were prepared 48 hours post transfection for expression analysis. (<b>B, C</b>) LLyECs were transduced with pLKO.1 lentiviruses encoding shRNA targeting <i>TAL1</i>, <i>LYL1</i>, <i>LMO2</i> or control shRNA. Puromycine-resistant populations were analyzed between 12 to 20 days after transduction. (<b>A. B</b>) <u>Top, bottom </u><i>ANG-2</i> and <i>LYL1</i> mRNA levels was analyzed by RT-q-PCR. The signals of <i>ANG-2</i> and <i>LYL1</i> mRNA were normalized to those of <i>GAPDH</i>. The data are shown relative to mRNA content from control siRNA-treated cells arbitrarily set at 1. Each bar is the mean +/− SD of three independent experiments. <u>Middle</u> Intracellular ANG-2, TAL1, LMO2 and LYL1 protein expression was analyzed by immunoblotting. β-ACTIN expression was monitored to control protein loading (the bar indicates two independent immunoblots). The images shown are representative of three independent experiments. **, <i>P</i><0.01; ***, <i>P</i><0.001. (<b>C</b>)<u> TAL1-, LYL1- or LMO2-depletion reduces constitutive ANG-2 secretion in culture medium. Lef</u>t: HUVECs were transfected with the indicated siRNA. 24 hours after transfection, medium was changed and ANG2 secretion into culture medium for 24 hours was measured by ELISA. <u>Right</u>: LLyECs were transduced with pLKO.1 lentiviruses encoding the indicated shRNA and puromycine-resistant cell populations were grown to confluence. ELISA was used to measure ANG2 release for 48 hours into the media. ANG-2 production is shown relative to cell number measured at the end of the culture. *, <i>P</i><0.05; **, <i>P</i><0.01; ***, <i>P</i><0.001.</p