A converse of Sturm’s separation theorem

We show that Sturm’s classical separation theorem on the interlacing of the zeros of linearly independent solutions of real second order two-term ordinary differential equations necessarily fails in the presence of a turning point in the principal part of the equation. Related results are discussed

The hereditary angioedema burden of illness study in Europe (HAE-BOIS-Europe) : background and methodology

Background: Hereditary angioedema (HAE) is a rare but serious disease marked by swelling attacks in the extremities, face, trunk, airway, or abdominal areas that can be spontaneous or the result of trauma and other triggers. It can be life-threatening due to the risk of asphyxiation. While there have been major advancements in our understanding of the immunogenetics of HAE, there are significant gaps in the literature regarding understanding of the humanistic and economic impact of the disease, particularly in Europe. The purpose of the HAE Burden of Illness Study-Europe (HAE-BOIS-Europe), the development and methodology of which is described here, is to better understand the management and impact of HAE from the patient perspective in Europe. Methods/Design: This is a cross-sectional study in which retrospective data were also collected being conducted in Denmark, Germany and Spain. The study is open to patients ages 12 and older with a diagnosis of HAE-I or HAE-II. Data collection includes: (i) a survey on individuals’ health care resource use, direct and indirect medical costs, impact on work and school, treatment satisfaction, and emotional functioning (via the Hospital Anxiety and Depression Scale); and (ii) one-on-one interviews to collect detailed descriptive data and patient testimonials on the impact of HAE on patients’ health-related quality of life. Discussion: The present manuscript describes the development and plans for implementing a multi-country European study with the aim of characterizing the humanistic and economic burden of HAE from the patient perspective. This study will help raise awareness of HAE as a rare but debilitating condition with wide-ranging impacts

A review of the application of acoustic emission technique in engineering

The use of acoustic emission (AE) technique for detecting and monitoring damages and the progress on damages in different structures is widely used and has earned a reputation as one of the most reliable and well-established technique in non-destructive testing (NDT). Acoustic Emission is a very efficient and effective technology used for fracture behavior and fatigue detection in metals, fiberglass, wood, composites, ceramics, concrete and plastics. It can also be used for detecting faults and pressure leaks in vessels, tanks, pipes, as well as for monitoring the progression of corrosion in welding. This paper reviews major research developments over the past few years in application of acoustic emission in numerous engineering fields, including manufacturing, civil, aerospace and material engineering

A rare presentation of late right coronary artery spasm following aortic valve replacement

BACKGROUND: Coronary artery spasm (CAS) is defined as a reversible, sudden epicardial coronary artery stenosis that causes vessel occlusion or near occlusion. CASE REPORT: In this article, we present a clinical case of CAS in a 48-year-old woman undergoing elective aortic valve replacement surgery for aortic stenosis. On the 3rd post-operative day, the patient suffered from chest pain and dyspnea. Emergent coronary angiography demonstrated a significant spasm of the ostium portion of the right coronary artery. CONCLUSION: This case shows that delayed coronary spasm should be considered as a cause of hemodynamic instability after valvular surgery. © 2015, Isfahan University of Medical Sciences(IUMS). All rights reserved

An Agent-based Architecture for AI-Enhanced Automated Testing for XR Systems, a Short Paper

This short paper presents an architectural overview of an agent-based framework called iv4XR for automated testing that is currently under development by an H2020 project with the same name. The framework's intended main use case of is testing the family of Extended Reality (XR) based systems (e.g. 3D games, VR sytems, AR systems), though the approach can indeed be adapted to target other types of interactive systems. The framework is unique in that it is an agent-based system. Agents are inherently reactive, and therefore are arguably a natural match to deal with interactive systems. Moreover, it is also a natural vessel for mounting and combining different AI capabilities, e.g. reasoning, navigation, and learning

Impact of vitamin C supplementation on post-cardiac surgery ICU and hospital length of stay

Background: Prolonged intensive care unit (ICU) and hospital stay after cardiac surgery is vitally important and is influenced by both intraoperative and postoperative factors.Objectives: This randomized clinical trial study was designed to assess whether vitamin C supplementation could reduce the length of ICU and hospital stay in post-cardiac surgery patients.Patients and Methods: Two hundred and ninety patients scheduled for adult cardiac surgery including coronary, valve and congenital operations were randomized into two groups: an intervention group, who received 2 g of vitamin C (ascorbic acid) intravenously, immediately before surgery in the operating theatre, followed by 1 g daily oral doses for the first 4 postoperative days; and a placebo group,who received an equal number of identical tablets in the same shape and size. Results: Hospital length of stay was significantly different between the two groups (10.17 ± 4.63 days in the intervention group vs. 12 ± 4.51 days in the placebo group; P = 0.01), while there was no significant difference in the ICU stay between the groups (3.42 ± 1.06 days in intervention group vs. 3.43 ± 1.09 days in the placebo group; P = 0.88). There were significant differences in the intubation time and the drainage volume in the ICU and the first 24 postoperative hours between the two groups (P for both = 0.003). Conclusions: Vitamin C can decrease the length of hospital stay, drainage volume in the ICU and in the first 24 postoperative hours, intubation time and some complications in patients after cardiac surgery; perhaps by decreasing inflammatory factors. Background: Prolonged intensive care unit (ICU) and hospital stay after cardiac surgery is vitally important and is influenced by both intraoperative and postoperative factors.Objectives: This randomized clinical trial study was designed to assess whether vitamin C supplementation could reduce the length of ICU and hospital stay in post-cardiac surgery patients.Patients and Methods: Two hundred and ninety patients scheduled for adult cardiac surgery including coronary, valve and congenital operations were randomized into two groups: an intervention group, who received 2 g of vitamin C (ascorbic acid) intravenously, immediately before surgery in the operating theatre, followed by 1 g daily oral doses for the first 4 postoperative days; and a placebo group,who received an equal number of identical tablets in the same shape and size. Results: Hospital length of stay was significantly different between the two groups (10.17 ± 4.63 days in the intervention group vs. 12 ± 4.51 days in the placebo group; P = 0.01), while there was no significant difference in the ICU stay between the groups (3.42 ± 1.06 days in intervention group vs. 3.43 ± 1.09 days in the placebo group; P = 0.88). There were significant differences in the intubation time and the drainage volume in the ICU and the first 24 postoperative hours between the two groups (P for both = 0.003). Conclusions: Vitamin C can decrease the length of hospital stay, drainage volume in the ICU and in the first 24 postoperative hours, intubation time and some complications in patients after cardiac surgery; perhaps by decreasing inflammatory factors. © 2015, Iranian Society of Regional Anesthesia and Pain Medicine (ISRAPM)

Voxel-based supervised machine learning of peripheral zone prostate cancer using noncontrast multiparametric MRI

Purpose: The aim of this study was to develop and assess the performance of supervised machine learning technique to classify magnetic resonance imaging (MRI) voxels as cancerous or noncancerous using noncontrast multiparametric MRI (mp-MRI), comprised of T2-weighted imaging (T2WI), diffusion-weighted imaging (DWI), and advanced diffusion tensor imaging (DTI) parameters. Materials and methods: In this work, 191 radiomic features were extracted from mp-MRI from prostate cancer patients. A comprehensive set of support vector machine (SVM) models for T2WI and mp-MRI (T2WI + DWI, T2WI + DTI, and T2WI + DWI + DTI) were developed based on novel Bayesian parameters optimization method and validated using leave-one-patient-out approach to eliminate any possible overfitting. The diagnostic performance of each model was evaluated using the area under the receiver operating characteristic curve (AUROC). The average sensitivity, specificity, and accuracy of the models were evaluated using the test data set and the corresponding binary maps generated. Finally, the SVM plus sigmoid function of the models with the highest performance were used to produce cancer probability maps. Results: The T2WI + DWI + DTI models using the optimal feature subset achieved the best performance in prostate cancer detection, with the average AUROC, sensitivity, specificity, and accuracy of 0.93 ± 0.03, 0.85 ± 0.05, 0.82 ± 0.07, and 0.83 ± 0.04, respectively. The average diagnostic performance of T2WI + DTI models was slightly higher than T2WI + DWI models (+3.52%) using the optimal radiomic features. Conclusions: Combination of noncontrast mp-MRI (T2WI, DWI, and DTI) features with the framework of a supervised classification technique and Bayesian optimization method are able to differentiate cancer from noncancer voxels with high accuracy and without administration of contrast agent. The addition of cancer probability maps provides additional functionality for image interpretation, lesion heterogeneity evaluation, and treatment management.</p

Molecular mechanisms related to colistin resistance in enterobacteriaceae

Colistin is an effective antibiotic for treatment of most multidrug-resistant Gram-negative bacteria. It is used currently as a last-line drug for infections due to severe Gram-negative bacteria followed by an increase in resistance among Gram-negative bacteria. Colistin resistance is considered a serious problem, due to a lack of alternative antibiotics. Some bacteria, including Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacteriaceae members, such as Escherichia coli, Salmonella spp., and Klebsiella spp. have an acquired resistance against colistin. However, other bacteria, including Serratia spp., Proteus spp. and Burkholderia spp. are naturally resistant to this antibiotic. In addition, clinicians should be alert to the possibility of colistin resistance among multidrug-resistant bacteria and development through mutation or adaptation mechanisms. Rapidly emerging bacterial resistance has made it harder for us to rely completely on the discovery of new antibiotics; therefore, we need to have logical approaches to use old antibiotics, such as colistin. This review presents current knowledge about the different mechanisms of colistin resistance. © 2019 Aghapour et al