Efficient adaptivity for simulating cardiac electrophysiology with spectral deferred correction methods

The locality of solution features in cardiac electrophysiology simulations calls for adaptive methods. Due to the overhead incurred by established mesh refinement and coarsening, however, such approaches failed in accelerating the computations. Here we investigate a different route to spatial adaptivity that is based on nested subset selection for algebraic degrees of freedom in spectral deferred correction methods. This combination of algebraic adaptivity and iterative solvers for higher order collocation time stepping realizes a multirate integration with minimal overhead. This leads to moderate but significant speedups in both monodomain and cell-by-cell models of cardiac excitation, as demonstrated at four numerical examples.Comment: 12 pages, 12 figure

Rare presentation of COVID-19 in 6-year-old girl: myocarditis with severe restrictive diastolic dysfunction

Since the emergence of COVID-19 in late December 2019, patients were presented at the hospitals with different symptoms, including cardiac manifestations. Recent records of coronavirus infection in children and adolescents have been accompanied by multisystem inflammatory syndrome (MIS-C). Here, we describe a 6 -year-old girl with no history of cardiac disease, infected with COVID-19 and presented at the emergency department with fever and cardiac manifestations. Her echocardiography findings favored myocarditis with restrictive (severe) diastolic dysfunction, a rare manifestation of COVID-19 among children. Unfortunately, despite standard treatment of myocarditis and supportive care, the patient passed away. Therefore, it seems necessary to develop a guideline for the recent cardiac consequences of the pandemic among children and follow their presentations carefully

Association between rs56066773 and rs56232250 polymorphisms of FOXP3 gene in target site of microRNA with rheumatoid arthritis in patients referred to Emam Ali clinic of Shahrekord

Background and aims: Rheumatoid arthritis is an autoimmune disease in which the numder or function of regulatory T cells (Treg) is impaired. FOXP3 is one of the major factors of Treg function. Among the factors involved on FOXP3 expression are microRNAs (MIR) which bind to 3´UTR. A nucleotide substitution in the sequence of the target site of microRNA can affect the regulation of microRNA. Polymorphisms of rs56066773 and rs56232250 in the 3´UTR of gene FOXP3 can relate with rheumatoid arthritis through the target gene. This study was aimed to investigate the relationship between two polymorphisms with rheumatoid arthritis. Methods: In this case-control study, 98 RA patients were recruited from Emam Ali rheumatology clinic and 124 healthy individuals (without the negative history of autoimmune diseases) served as control. Rs56066773 and rs56232250 polymorphisms in the 3´UTR of FOXP3 gene were investigated with Polymerase Chain Reaction (PCR)- Restricted Fragment Length Polymorphism (RFLP). The data were analyzed using SPSS. Results: In the study population, the frequency of the A/G in rs56066773 in patients and control was 3.1 and 1.6%, respectively. The frequency of the same genotype in rs56232250 was 1 and 1.6% in patients and controls respectively. It was not found any significant relationship between two polymorphism and disease. Conclusion: Although not found a significant relationship between polymorphisms and arthritis, previous studies has been established the relationship between polymorphisms in the microRNA target site with a number of diseases. Therefore, it is necessary to examine other FOXP3 gene 3'UTR polymorphisms

Investigating the role of predictive death anxiety in the job satisfaction of pre‑hospital emergency personnel during the COVID‑19 pandemic

Background: Pre-hospital emergency staffs as the frontline forces fighting against COVID -19 have been affected by this pandemic. Today, the occupational and mental health of these individuals is particularly important to the health care system. Death anxiety is one of the inevitable things in this job, and not paying attention to it can cause unwanted effects such as changing the level of job satisfaction of the personnel. The purpose of this study was to determine the role of predictive death anxiety in the job satisfaction of pre-hospital emergency personnel during the COVID-19 pandemic. Methods: This cross-sectional descriptive study was conducted among pre-hospital emergency staffs in Qazvin Province, Iran in 2021–2022. Among the bases chosen by the census method, 198 samples were included in the study by the available method. Data collection tools included the Demographic Checklist, Templer’s Death Anxiety scale, and the Minnesota Job Satisfaction Questionnaire. The data were analyzed with descriptive and inferential statistics and SPSS 20 software. Results: The mean age of the samples was (33.14 ± 6.77). 167 persons were male and the others were female. The average job satisfaction and death anxiety of the personnel were 55.07 ± 11.50 and 8.18 ± 1.96, respectively. Pearson’s correlation coefficient between the two variables was r = -0.126 And a null correlation coefficient hypothesis has been confirmed with p-value = 0.077. Conclusions: The results showed a high level of death anxiety and average job satisfaction. Although these two variables do not have a significant relationship with each other, considering that they do not have the appropriate level, it needs more investigation and consideration

Interactive visual labelling versus active learning: an experimental comparison

Methods from supervised machine learning allow the classification of new data automatically and are tremendously helpful for data analysis. The quality of supervised maching learning depends not only on the type of algorithm used, but also on the quality of the labelled dataset used to train the classifier. Labelling instances in a training dataset is often done manually relying on selections and annotations by expert analysts, and is often a tedious and time-consuming process. Active learning algorithms can automatically determine a subset of data instances for which labels would provide useful input to the learning process. Interactive visual labelling techniques are a promising alternative, providing effective visual overviews from which an analyst can simultaneously explore data records and select items to a label. By putting the analyst in the loop, higher accuracy can be achieved in the resulting classifier. While initial results of interactive visual labelling techniques are promising in the sense that user labelling can improve supervised learning, many aspects of these techniques are still largely unexplored. This paper presents a study conducted using the mVis tool to compare three interactive visualisations, similarity map, scatterplot matrix (SPLOM), and parallel coordinates, with each other and with active learning for the purpose of labelling a multivariate dataset. The results show that all three interactive visual labelling techniques surpass active learning algorithms in terms of classifier accuracy, and that users subjectively prefer the similarity map over SPLOM and parallel coordinates for labelling. Users also employ different labelling strategies depending on the visualisation used

Energy savings from flash steam recovery: An industrial case study

In oil, gas and petrochemical production complexes, steam pressure boosting technology is used to recover low-pressure steam, using both mechanical and thermal solutions to increase energy efficiency. The heat recovery from steam, especially flash steam produced in the return condensate lines, can be considered an economic and attractive solution. In an industrial case study in a gas plant located in the south-west of Iran, the LP condensate returns to the LP condenser waste with a flow rate of 96,000 kg/h and a pressure of 0.45 bar. As a result of the pressure drop, about 6800 kg/h of flash steam is generated. Therefore, in order to recover, the first the return condensate current enters a flash drum to separate the amount of steam produced by the flash operation. In this research, two strategies for increasing the pressure using a steam compressor and an ejector have been investigated. The simulation results show that flash steam recycling using steam compressors and ejectors results in energy saving for the refinery of about one million and USD100k per year, and also about 152 and 137 thousand tons equivalent to carbon dioxide emissions per year are reduced, respectively

Evaluation of possible toxic effects of spearmint (Mentha spicata) on the reproductive system, fertility and number of offspring in adult male rats

Objective: In this study we investigated the effects of spearmint (Mentha spicata Labiatae) on the reproductive system, fertility and number of offspring in adult male rats. Materials and Methods: Adult Wistar male rats in one control (C) and three experimental groups (I, II and III) received 0, 10, 20 and 40 mg/kg spearmint extract orally for 45 days, respectively.  Following this treatment, the animals’ weights, and the standard weight of reproductive tissues, sperm count, sperm motility and serum testosterone concentration were measured, and reproductive tissues were examined histopathologically. To evaluate the effects of spearmint on fertility of male rats and growth of their offspring, male rats of the control and experimental groups mated with untreated female rats. Results: Results showed that spearmint did not affect the rats’ body and reproductive tissue weights. The sperm count, fast and slow progressive motility of sperm and serum testosterone concentration decreased while number of non-progressive sperm and immotile sperm increased in the experimental groups compared to the control group, but none of these changes were statistically significant. Histopathological studies showed no severe changes in reproductive tissues between control and experimental groups. Number and growth of offspring born from mating of male rats with untreated female rats showed no difference. Conclusion: We concluded that spearmint has no significant toxic effect on the reproductive system, fertility and number of offspring in adult male rats at the above  mentioned dose levels. However high levels of this extract may have adverse effects on male fertility