Testing and Diagnostics of Carbon Polymer Composite Materials by Radio Wave Method Used in Aircraft Construction

The article is devoted to the applicability of radio wave methods of testing and diagnostics of aviation composites for newly launched products. The description of the measurement process is also considered by the method of integral equations.

Comparison of efficacy of laser and radio-wave methods of surgical treatment of patients with chronic rhinitis

Introduction. Chronic rhinitis occurs more often in patients; it’s symptoms deteriorate their quality of life, affect sleeping, daily activity, and sometimes cause complications. The treatment depends on the clinical symptoms. In case of inefficiency of conservative therapy, surgery is indicated. Choosing an exact surgical instrument is still controversial.Objective. The aim of our study is to compare using semiconductor laser (wavelength 1.56 mkm) and radiofrequency (4 MHz) in patients with chronic rhinitis.Materials and methods. 60 patients with chronic drug-induced rhinitis aged 19–80 years were recruited and divided into two equal groups. All patients underwent surgical procedures: semiconductor laser (IRE-Polus) and radiofrequency (Ellman Surgitron) inferior nasal turbinate reduction. To assess and compare the healing process in two groups we used endoscopy and active anterior rhinomanometry. All patients filled out the SNOT-20 questionnaire. For the mucociliary clearance evaluation saccharin test was used. We observed patients during 12 months.Conclusion. Both, laser and radiofrequency, techniques are effective in patients with chronic rhinitis. In laser group shorter healing period was observed, what leads to rehabilitation shortening and life quality improvement.

Determinants of adherence to COVID-19 preventive behaviours in Canada: Results from the iCARE Study

Objective: Key to slowing the spread of SARS-Cov-2 is adherence to preventive behaviours promoted through government policies, which may be influenced by policy awareness, attitudes and concerns about the virus and its impacts. This study assessed determinants of adherence to major coronavirus preventive behaviours, including demographics, attitudes and concerns, among Canadians during the first pandemic wave. Methods: As part of the iCARE study (www.iCAREstudy.com), we weighted data from two population-based, online surveys (April and June, 2020) of Canadian adults. Questions tapped into behaviour change constructs. Multivariate regression models identified determinants of adherence. Results: Data from 6,008 respondents (51% female) were weighted for age, sex, and province. Awareness of government policies was high at both time points (80-99%), and adherence to prevention behaviours was high in April (87.5%-93.5%) but decreased over time, particularly for avoiding social gatherings (68.1%). Adherence was worse among men, those aged 25 and under, and those currently working. Aligned with the Health Beliefs Model, perceptions of the importance of prevention behaviours and the nature of peoples COVID-19-related concerns were highly predictive of adherence. Interestingly, health and social/economic concerns predicted better adherence, but having greater personal financial concerns predicted worse adherence at both time points. Conclusion: Adherence to COVID-19 prevention behaviours was worse among men, younger adults, and workers, and deteriorated over time. Perceived importance of prevention behaviours measures and health and social/economic concerns predicted better adherence, but personal financial concerns predicted worse adherence. Results have implications for tailoring policy and communication strategies during subsequent pandemic waves.

Tracking deaths can provide an indicator of latent COVID19 cases

Background: With countries across the world facing repeated epidemic waves, it becomes critical to monitor, mitigate and prevent subsequent waves. Common indicators like active case numbers can flatter to deceive in the presence of systemic inefficiencies like insufficient testing or contact tracing. Test positivity rates are sensitive to testing strategies and cannot estimate the extent of undetected cases. Reproductive numbers estimated from logarithms of new incidences are inaccurate in dynamic scenarios and not sensitive enough to capture changes in efficiencies. Systemic fatigue results in lower testing, inefficient tracing and quarantining thereby precipitating the onset of the epidemic wave. Methods: We propose a novel indicator for detecting the slippage of test-trace efficiency based on the numbers of deaths/hospitalizations resulting from known and hitherto unknown infections. This can also be used to forecast an epidemic wave that is advanced or exacerbated due to drop in efficiency. Results: Using a modified SEIRD epidemic simulator we show that (i) Ratio of deaths/hospitalizations from an undetected infection to total deaths converges to a measure of systemic test-trace inefficiency. (ii) This index forecasts the slippage in efficiency earlier than other known metrics. (iii) Mitigation triggered by this index helps reduce peak active caseload and eventual deaths. Conclusions: Deaths/hospitalizations accurately track the systemic inefficiencies and detect latent cases. Based on these results we make a strong case that administrations use this metric in the ensemble of indicators. Further hospitals may need to be mandated to distinctly register deaths/hospitalizations due to previously undetected infections. Keywords: Covid19 Epidemic Epidemiology Mathematical model Death rates

COVID-19 in patients hospitalized and healthcare workers: what have changed after the first wave in a university hospital

Objective: To assess the COVID-19 frequency rates in hospitalized patients (HP) and healthcare workers (HCW), viral load inference, and the impact of vaccination and variants of concern (VOC) during the first pandemic wave. Methods: We evaluated the COVID-19 diagnostics at Hospital Sao Paulo, Brazil, from March 2020 to April 2021, in 10,202 samples (6,502 HP and 3,700 HCW) tested by RT-qPCR, inferring viral load by cycle threshold (Ct) values, and frequency rates. Results: SARS-CoV-2 was detected in 31.27% of individuals (32.23% HP and 29.80% HCW). The mean age of HP positives was 57.26 +/- 18.29 years (median = 59), with a mean Ct value of 25.55 +/- 6.07. Neither age nor Ct values in both groups have significantly differed during the first and second waves or even since the predominance of VOC P.1 on March 2021. Conclusions: The COVID-19 epidemic curves of HP and HCW accompanied the variations reported in Sao Paulo city, as well as the variation of hospitalization and occupancy of ICU beds. The VOC P.1 has no impact on the viral load, since its predominance in March 2021. The vaccination of HCW may have contributed to a decrease in the positivity rates, although more studies will provide a better understanding of the impact of immunization on the COVID-19 pandemic.

Stress evaluation in seven-wire strands based on singular value feature of ultrasonic guided waves

The seven-wire strands are the crucial components of prestressed structures, though their performance inevitably degrades with the passage of time. The ultrasonic guided wave methods have been intensely studied, owing to its tremendous potential for full-scale applications, among the existing nondestructive testing methods, for evaluating the stress status of strands. We have employed the theoretical and finite element methods to solve the dispersion curve of single wire and steel strands under various boundary conditions. Thereafter, the singular value decomposition was adopted to work with the simulated and experimental signals for extracting a feature vector that carries valuable stress status information. The effectiveness of the vector was verified by analyzing the relationship between the vector and the stress level. The vector was also used as an input to establish a support vector regression model. The accuracy of the model has been discussed for different sample sizes. The results show that the fundamental mode dispersion curve offset on the high-frequency part and cut-off frequency increases as the boundary constraints enhance. Simulated and experimental results have demonstrated the effectiveness and potential of the proposed support vector regression method for evaluating the stress level in the strands. This method performs well even at low stress levels and the reliability can be enhanced by adding more samples.