Compressed Sensing Performance Analysis via Replica Method using Bayesian framework

Compressive sensing (CS) is a new methodology to capture signals at lower rate than the Nyquist sampling rate when the signals are sparse or sparse in some domain. The performance of CS estimators is analyzed in this paper using tools from statistical mechanics, especially called replica method. This method has been used to analyze communication systems like Code Division Multiple Access (CDMA) and multiple input multi- ple output (MIMO) systems with large size. Replica analysis, now days rigorously proved, is an efficient tool to analyze large systems in general. Specifically, we analyze the performance of some of the estimators used in CS like LASSO (the Least Absolute Shrinkage and Selection Operator) estimator and Zero-Norm regularizing estimator as a special case of maximum a posteriori (MAP) estimator by using Bayesian framework to connect the CS estimators and replica method. We use both replica symmetric (RS) ansatz and one-step replica symmetry breaking (1RSB) ansatz, clamming the latter is efficient when the problem is not convex. This work is more analytical in its form. It is deferred for next step to focus on the numerical results.Comment: The analytical work and results were presented at the 2012 IEEE European School of Information Theory in Antalya, Turkey between the 16th and the 20th of Apri

Mesoscale mapping of sediment source hotspots for dam sediment management in data-sparse semi-arid catchments

Land degradation and water availability in semi-arid regions are interdependent challenges for management that are influenced by climatic and anthropogenic changes. Erosion and high sediment loads in rivers cause reservoir siltation and decrease storage capacity, which pose risk on water security for citizens, agriculture, and industry. In regions where resources for management are limited, identifying spatial-temporal variability of sediment sources is crucial to decrease siltation. Despite widespread availability of rigorous methods, approaches simplifying spatial and temporal variability of erosion are often inappropriately applied to very data sparse semi-arid regions. In this work, we review existing approaches for mapping erosional hotspots, and provide an example of spatial-temporal mapping approach in two case study regions. The barriers limiting data availability and their effects on erosion mapping methods, their validation, and resulting prioritization of leverage management areas are discussed.BMBF, 02WGR1421A-I, GROW - Verbundprojekt SaWaM: Saisonales Wasserressourcen-Management in Trockenregionen: Praxistransfer regionalisierter globaler Informationen, Teilprojekt 1DFG, 414044773, Open Access Publizieren 2019 - 2020 / Technische Universität Berli

Bayesian Inference and Compressed Sensing

This chapter provides the use of Bayesian inference in compressive sensing (CS), a method in signal processing. Among the recovery methods used in CS literature, the convex relaxation methods are reformulated again using the Bayesian framework and this method is applied in different CS applications such as magnetic resonance imaging (MRI), remote sensing, and wireless communication systems, specifically on multiple-input multiple-output (MIMO) systems. The robustness of Bayesian method in incorporating prior information like sparse and structure among the sparse entries is shown in this chapter

DRESS syndrome due to clobazam: a case report

Drug rash (or reaction) with eosinophilia and systemic symptoms (DRESS) is a potentially life-threatening hypersensitivity reaction to drugs characterized by rash, fever, lymphadenopathy, hematologic abnormalities, and involvement of internal organs. Initially coined in 1996, the term is used to refer to an idiosyncratic reaction to several drugs, the most common of which are carbamazepine, allopurinol, sulfasalazine, and phenobarbital. We report the case of DRESS related to clobazam in a 38-year-old female with a history of a complex seizure disorder

Prediction of viral microRNA precursors based on human microRNA precursor sequence and structural features

MicroRNAs (small ~22 nucleotide long non-coding endogenous RNAs) have recently attracted immense attention as critical regulators of gene expression in multi-cellular eukaryotes, especially in humans. Recent studies have proved that viruses also express microRNAs, which are thought to contribute to the intricate mechanisms of host-pathogen interactions. Computational predictions have greatly accelerated the discovery of microRNAs. However, most of these widely used tools are dependent on structural features and sequence conservation which limits their use in discovering novel virus expressed microRNAs and non-conserved eukaryotic microRNAs. In this work an efficient prediction method is developed based on the hypothesis that sequence and structure features which discriminate between host microRNA precursor hairpins and pseudo microRNAs are shared by viral microRNA as they depend on host machinery for the processing of microRNA precursors. The proposed method has been found to be more efficient than recently reported ab-initio methods for predicting viral microRNAs and microRNAs expressed by mammals

The potential of general practice to support young people who self-harm: a narrative review

Background Self-harm in young people is a growing public health concern. Young people commonly present to their GP for help with self-harm, and thus general practice may be a key setting to support young people who have self-harmed. Aim To examine the potential of general practice to support young people aged 10–25 years who have harmed themselves. Design & setting A narrative review of published and grey literature. Method The Scale for the Assessment of Narrative Review Articles (SANRA) was used to guide a narrative review to examine the potential of general practice to support young people who have self-harmed. The evidence is presented textually. Results The included evidence showed that GPs have a key role in supporting young people, and they sometimes relied on gut feeling when handling uncertainty on how to help young people who had self-harmed. Young people described the importance of initial clinician responses after disclosing self-harm, and if they were perceived to be negative, the self-harm could become worse. Conclusion In context of the evidence included, this review found that general practice is a key setting for the identification and management of self-harm in young people; but improvements are needed to enhance general practice care for young people to fulfil its potential

Predictors of serious findings on bi-directional endoscopy in young patients with anemia and GI symptoms

Background: Iron deficiency anemia (IDA) has been cited as the most common cause of anemia globally. Gastrointestinal (GI) lesions are amongst the common cause of IDA. Endoscopic evaluation is the most effective way to investigate the IDA. The aim of this study was to show the association of alarming GI symptoms with abnormal endoscopic findings and to cut off the burden and cost of unnecessary endoscopies. Methods: This is cross sectional study of anemic patient who underwent upper and lower GI endoscopies in Aga Khan University Hospital, Karachi between July-December 2016. Results: Total 243 patients were identified after excluding ineligible patients. The mean age of subjects was 31.9 ± 6.1 years with a slight over-representation of females (57.4%). 149 (61.31%) patients underwent only upper GI endoscopic evaluation, and 83 (34.15%) patients on whom bi-directional endoscopy was performed (upper and lower). The remaining 11 (4.52%) patients underwent colonoscopy only. 16 (6.6%) subjects had negative findings on evaluation, while gastritis and serious findings were observed in 175 (72.0%) and 52 (21.4%) patients respectively. We found that patients with alarm features such as dysphagia (aOR: 2.07, 95%CI: 0.12-34.1), altered bowel habits (aOR: 1.64, 95%CI: 0.44-6.09) and weight loss (aOR: 1.25 95%CI: 0.54-2.85) demonstrated higher odds of serious findings on endoscopic evaluation as compared to the reference category, however they were not independently associated. Conclusion: Most of our patients had non-malignant pathologies, while alarm features were not found to be useful predictors of serious findings