Aligning Cross-lingual Sentence Representations with Dual Momentum Contrast

In this paper, we propose to align sentence representations from different languages into a unified embedding space, where semantic similarities (both cross-lingual and monolingual) can be computed with a simple dot product. Pre-trained language models are fine-tuned with the translation ranking task. Existing work (Feng et al., 2020) uses sentences within the same batch as negatives, which can suffer from the issue of easy negatives. We adapt MoCo (He et al., 2020) to further improve the quality of alignment. As the experimental results show, the sentence representations produced by our model achieve the new state-of-the-art on several tasks, including Tatoeba en-zh similarity search (Artetxe andSchwenk, 2019b), BUCC en-zh bitext mining, and semantic textual similarity on 7 datasets.

Multi-stage Training with Improved Negative Contrast for Neural Passage Retrieval

In the context of neural passage retrieval, we study three promising techniques: synthetic data generation, negative sampling, and fusion. We systematically investigate how these techniques contribute to the performance of the retrieval system and how they complement each other. We propose a multi-stage framework comprising of pre-training with synthetic data, fine-tuning with labeled data, and negative sampling at both stages. We study six negative sampling strategies and apply them to the fine-tuning stage and, as a noteworthy novelty, to the synthetic data that we use for pre-training. Also, we explore fusion methods that combine negatives from different strategies. We evaluate our system using two passage retrieval tasks for open-domain QA and using MS MARCO. Our experiments show that augmenting the negative contrast in both stages is effective to improve passage retrieval accuracy and, importantly, they also show that synthetic data generation and negative sampling have additive benefits. Moreover, using the fusion of different kinds allows us to reach performance that establishes a new state-of-the-art level in two of the tasks we evaluated.

Improving Faithfulness in Abstractive Summarization with Contrast Candidate Generation and Selection

Despite significant progress in neural abstractive summarization, recent studies have shown that the current models are prone to generating summaries that are unfaithful to the original context. To address the issue, we study contrast candidate generation and selection as a model-agnostic post-processing technique to correct the extrinsic hallucinations (i.e. information not present in the source text) in unfaithful summaries. We learn a discriminative correction model by generating alternative candidate summaries where named entities and quantities in the generated summary are replaced with ones with compatible semantic types from the source document. This model is then used to select the best candidate as the final output summary. Our experiments and analysis across a number of neural summarization systems show that our proposed method is effective in identifying and correcting extrinsic hallucinations. We analyze the typical hallucination phenomenon by different types of neural summarization systems, in hope to provide insights for future work on the direction.

The Impact of Contrast in Poeticizing a Text : An Interpretation of al-Mutanabby’s “ I Do Cherish You Should the Soul Be Taciturn”

A text’s poetic characteristic is what gives it its literary attribute .The poetic characteristic of a structural constituent is what gives it the main attribute amongst others. Scholars, therefore, are interested when attempting to identify the poetic quality in tracing the technique, whose effective presence, along with its links to other set constituents, indicates that the studied text is distinguished for its poetic characteristic .Each artistic means, which is significant in indicating the implication of the text, is a poetic means. This is the paper’s hypothesis in illustrating the significance of contrast, relying upon a set of theoretical postulates, of which some are confined to linguistics, although they have their basis in Arab linguistic and rhetorical discourse. They help a scholar in drawing rhetorical conclusions, in the aftermath of examining the texts. As for the practical objective, the paper will try to make use of the theoretical postulates in dealing with one of al- Mutanabby’s texts, which are strikingly rich with contrasts: their abundance on the text's level. Thus , al-Mutanabby invested it [contrast] in weaving a network of relations linking the signified, whereby contrast is their main linking device, and the first controlling factor in directing them towards giving the text a consistent poetic structure.

Risk factors for contrast induced nephropathy among patients undergoing coronary angiography or percutaneous coronary intervention

Prevention is the key to reduce the incidence of Contrast-induced nephropathy (CIN) and it begins with identification of the high risk patients. Aim: Identifying the different risk factors for CIN . Methods: This is a prospective analytical study that has included 156 patients, all underwent an objective exam, hematochemical measurements. The patiemts were divided into two groups depending on the incidence of CIN defined as an increase in creatinine level equal or more than 25% from baseline values within 48-72 hours after the coronary procedure. Results: Several independent risk factors for CIN were identified: age equal or more 70 year (OR:4.11, P:0.004( , contrast volume more than 200 ml )OR:3.2,P:0.01(, anemia (OR:2.7,P:0.01), urgent cardiac catheterization) OR:3.3,P:0.02(,diabetic nephropathy (OR:4.9,P:0.04). Conclusion: . Increased contrast volume ,urgent cardiac catheterization elderly patients , anemia and diabetic nephropathy are associated with increased risk for CIN.

The Antibody Diodes in Al Ahwas Al-Ansari' poetry

This research studies the phenomenon of contrast that was manifested in the poetry of Al Ahwas Al-Ansari ,taking different colors ,between the singularity and the composition or the metaphorical image that the poet intended to find to create a tangled word of relation embraced by the language of poetry.

Study of surgical treatment outcome for esophageal atresia

The research aims to make a statistical approach to the cases of esophageal atresia by its types and incidence, and to study the surgical treatment outcome and choose the best method of treatment and follow up. The study included 27 newborn patients admitted in the Neonatal Intensive Care Unit at Al-Assad University Hospital and Tishreen University Hospital in Lattakia, due to diagnosis of esophageal atresia or tracheoesophageal fistula, from the beginning of January 2010 until the end of 2015. 14 of patients were males and 13 were females. Gross classification of esophageal atresia was used, type (C) was found in 21 cases, type (A) was found in 4 cases, type (E) was found in 2 cases, while type (B) and (D) were not seen. We studied The clinical symptoms in newborn patients with this malformation, radial and laboratory findings and associated malformations. We used esophageal contrast study insure the diagnosis when needed. With type (C), we did primary anastomosis in 20 cases and cervical esophagostomy with gastrostomy in only 1 case. With type (A), we did esophagostomy with gastrostomy in all cases. With type (E), we closed the fistula with cervical approach in all cases. The survival rate was 70.4%. Spitz classification was used for risk assessment. The incidence of complications included anastomotic leakage 30% and anastomotic stricture 69.2%.

Using Top-Hat and Bottom-Hat Transforms for Contrast Enhancement of Mammograms

Mammography is widely used technique for breast cancer screening. There are various other techniques for breast cancer screening but mammography is the most reliable and effective technique. The images obtained through mammography are of low contrast which causes problem for the radiologists to interpret. Hence, a high quality image is mandatory for the processing of the image for extracting any kind of information. Many contrast enhancement algorithms have been developed over the years. This work presents a method to enhancement Microcalcifications in digitized mammograms. The method is based Mainly on the combination of Image Processing. The top-Hat and bottom–hat transforms are a techniques based on Mathematical morphology operations. This algorithm has been tested on mini-Mias database which have three types of breast tissues . For evaluation of performance of image enhancement algorithm, the Contrast Improvement Index (CII) and Peak Signal to Noise Ratio (PSNR) have been used. Experimental results suggest that algorithm can be improve significantly overall detection of the Computer-Aided Diagnosis (CAD) system especially for dense breast.

The Relation Between Thrombus , Spontaneous Echo Contrast , And Left Atrial Appendage Velocity In Patients With Ischemic Stroke

Cardiogenic embolism can be identified in at least 15% of ischemic stroke patients, left atrial appendage is believed to be the place where thrombi is performed, then goes to systemic circulation causing embolic accident . In this search we study the function of left atrial appendage by pulse Doppler within the proximal third of the appendage in patients with ischemic stroke. Thrombus was defined as a discrete echocardiographically dens mass within the body of atrium or the appendage, with a different echocardiographically density than the adjacent endothelium . Spontaneous echo contrast was defined as high density flow due to low flow condition , which remains stable with changes in gain setting . In conclusion , the velocities which recorded in patients with ischemic stroke were lower in comparison with other patients , and it was significant lower in patients with spontaneous echo contrast or atrial fibrillation .