Simultaneous Sparse Approximation Using an Iterative Method with Adaptive Thresholding

This paper studies the problem of Simultaneous Sparse Approximation (SSA). This problem arises in many applications which work with multiple signals maintaining some degree of dependency such as radar and sensor networks. In this paper, we introduce a new method towards joint recovery of several independent sparse signals with the same support. We provide an analytical discussion on the convergence of our method called Simultaneous Iterative Method with Adaptive Thresholding (SIMAT). Additionally, we compare our method with other group-sparse reconstruction techniques, i.e., Simultaneous Orthogonal Matching Pursuit (SOMP), and Block Iterative Method with Adaptive Thresholding (BIMAT) through numerical experiments. The simulation results demonstrate that SIMAT outperforms these algorithms in terms of the metrics Signal to Noise Ratio (SNR) and Success Rate (SR). Moreover, SIMAT is considerably less complicated than BIMAT, which makes it feasible for practical applications such as implementation in MIMO radar systems

Exploitation of Stragglers in Coded Computation

In cloud computing systems slow processing nodes, often referred to as "stragglers", can significantly extend the computation time. Recent results have shown that error correction coding can be used to reduce the effect of stragglers. In this work we introduce a scheme that, in addition to using error correction to distribute mixed jobs across nodes, is also able to exploit the work completed by all nodes, including stragglers. We first consider vector-matrix multiplication and apply maximum distance separable (MDS) codes to small blocks of sub-matrices. The worker nodes process blocks sequentially, working block-by-block, transmitting partial per-block results to the master as they are completed. Sub-blocking allows a more continuous completion process, which thereby allows us to exploit the work of a much broader spectrum of processors and reduces computation time. We then apply this technique to matrix-matrix multiplication using product code. In this case, we show that the order of computing sub-tasks is a new degree of design freedom that can be exploited to reduce computation time further. We propose a novel approach to analyze the finishing time, which is different from typical order statistics. Simulation results show that the expected computation time decreases by a factor of at least two in compared to previous methods

COVID-19 in Children With Inflammatory Bowel Disease: A Systematic Review

Background: Considering the chronic immunosuppression in Inflammatory Bowel Disease (IBD) patients, it is necessary to evaluate the course of COVID-19 in these patients. Studies have shown various results in adult IBD patients. This study aimed to find out the course of this infection in pediatric IBD patients.  Methods: This was a systematic review study according to the PRISMA 2020 guideline. International databases including Scopus, PubMed, and the Web of Science were searched with a combination of “COVID-19” AND “IBD” or synonyms until October 16, 2021. Studies that have reported the outcomes of COVID-19 infection in patients less than 19 years of age were selected. Name of author, country, study duration and type, IBD type and drugs, and COVID-19 outcomes were extracted. Results: From the initially retrieved 2215 articles, finally 16 articles were eligible. Data from 1040 pediatric IBD patients were reported. Twenty-four patients were hospitalized, 5 developed patients multisystem inflammatory syndrome in children, and others had a mild disease course and were outpatient. Steroid use, severe IBD activity, and comorbidities were shown to increase risk of hospitalization and disease severity. Conclusions: COVID-19 is a benign and self-limited disease in pediatric IBD patients. Comorbidities, steroid use, and severe IBD activity affect the outcomes

Evaluation of factors affecting on the incidence of anxiety disorders and generalized anxiety in children in Bushehr in 2019: *Anxiety in preschool children

زمینه و اهداف: اختلالات اضطرابی، شایعترین اختلال روانی کودکان است که شیوع بالایی در ایران دارد. شناسایی علل و  تشخیص زود هنگام این گروه از اختلالات  می‌تواند اثرات طولانی مدت آن را به حداقل برساند.لذا هدف از این مطالعه بررسی عوامل‌ مؤثر در بروز اختلالات اضطرابی و اضطراب فراگیر درکودکان شهر بوشهر می‌باشد. مواد و روش‌ها: این مطالعه از نوع مقطعی است که در سال ۱۳۹۸ در شهر بوشهر انجام شد. جامعه پژوهش، تمام کودکان ۴تا ۶ سال پیش دبستانی و مهدکودک های این شهر بودندکه به صورت خوشه ای از بین آنها ، نمونه ای به حجم  428 انتخاب شد. ابزار پژوهش، پرسشنامه سنجش اضطراب اسپنس (فرم والدین) بود. به منظور توصیف و تجزیه و تحلیل داده‌ها از روش‌های آمار توصیفی (فراوانی و درصد) و آمار استبناطی (آنالیز واریانس یک طرفه و آزمون تعقيبي شفه) در سطح معنی‌داری 5 درصد در محیط نرم افزار SPSS نسخه ۲۴ استفاده گردید. یافته­ ها: تعداد اعضای خانواده (003/0=P-value)، تحصیلات پدر (00۱/0=P-value) و مادر (00۱/0=P-value)، وضعیت اشتغال پدر (0۳/0=P-value) و جدايي والدین از یکدیگر (00۲/0=P-value)، نوع سرپرست (00۱/0P-value<) و سابقه رویداد ناخوشایند               (00۱/0 P-value<) در بروز اضطراب فراگیر کودکان موثر بودند. همچنین  بروز همه انواع اختلالات اضطرابی مورد بررسی، سطح تحصیلات والدین ، سابقه رویداد ناخوشایند و تعداد اعضای خانواده (به جز در جراحات جسمانی) نقش داشته­اند. نتیجه‌گیری: براساس یافته‌های این پژوهش، عوامل اجتماعی و فرهنگی خانواده نقش زیادی در اضطراب کودکان دارد. بنابراین لازم است آموزش‌های والدین جهت پیشگیری از ابتلا کودکان به اضطراب، مد نظر سیاست‌گذاران حوزه سلامت قرار گیرد.Background and Aims: Anxiety disorders are the most common mental disorders in children, which are highly prevalent in Iran. Identifying the causes and early diagnosis of this group of disorders can minimize its long-term effects. The aim of this study was to investigate the factors affecting in the incidence of generalized anxiety and anxiety disorders in children in Bushehr.  Materials and Methods: This cross-sectional study was conducted in Bushehr in 2019. The study population consisted of all children aged 4 to 6 years of preschool and kindergartens of this city, among whom a sample of 428 was selected by multi-stage cluster sampling method. The research instrument was the Spence Anxiety Inventory (Parent Form). In order to describe and analyze the data, descriptive statistics (frequency and percentage) and based statistics (one-way analysis of variance and Scheffe post hoc test) were used at a significant level of 5% in SPSS software version 24. Results: The number of family members (p-value = 0.003), father's education (p-value = 0.001) and mother's education (p-value = 0.001), father's employment status (p-value = 0.03) and parental separation (p-value = 0.002), type of caregiver (p-value < 0.001) and unpleasant events history (p-value < 0.002) were effective in the incidence of generalized anxiety in children. Also, all types of anxiety disorders, parents' education level, unpleasant event history and number of family members (except in physical injuries) have played a role. Conclusion: According to the findings of this study, social and cultural factors of the family play a major role in children's anxiety. Therefore, it is necessary that parents' education to be considered by health policy makers to prevent children from developing anxiety