ПЕРФУЗІЙНА ДИСФУНКЦІЯ ПРИ ГОСТРОМУ ПАНКРЕАТИТІ: ПЕРСПЕКТИВНІ НАПРЯМКИ УДОСКОНАЛЕННЯ ДІАГНОСТИКИ ТА СТРАТИФІКАЦІЇ ЗАХВОРЮВАННЯ

Introduction. Acute pancreatitis (AP) is one of the most common diseases of the digestive system that require hospitalization. To date, the problem of stratification and differential diagnosis of AP in the early stages remains unresolved, which encourages the search for new methods of diagnosis and prediction of the severity of AP. Aim. To evaluate the possibility of creating a clinically oriented system of stratification and prognosis of AP on the basis of dynamic changes in microcirculation depending on the duration of the disease and severity of AP. Materials and methods. Assessment of the state of microcirculation (MC) of patients by laser Doppler flowmetry (LDF) was performed with the “LAKK-02” device. Kruskal-Wallis non-parametric analysis of variance and the median test were used to test statistical hypotheses when comparing independent samples. Pairwise comparison of independent samples was performed using the Mann-Whitney U test. Results. The study determined the indicators of MC in patients with different AP severity degrees on the first day of the disease. The microcirculation parameter (MP) in patients with mild, moderate, and severe AP was 3.9; 3.8 and 6.8 perfusion units (p.u.), respectively. The blood flow modulation rate (ơ) was 0.52; 0.54 and 0.69 p.u. in mild, moderate, and severe AP. In our study, the coefficient of variation (Kv) averaged 17.3%; 20.0% and 11.7% in patients with mild, moderate, and severe AP, respectively. Conclusions. LDF in AP is an informative method of diagnosing the state of MC, which is a universal link in all pathophysiological reactions of the organism. Changes of MC in AP depend on the severity of AP and the period of the disease. The pathophysiological microcirculatory phenomena, revealed on the first day of the disease, provide us with the perspectives of early clinical distinguishing the moderate and severe forms of AP from the so-called group of “destructive forms”.

LFM/PRBC Modulation Signal Parameter Estimation

Since pseudo-code phase modulation and carrier frequency modulation composite reconnaissance signals have both the good anti-interference capability and the low probability of interception, they have been widely used in electronic reconnaissance systems. This paper proposes a multi-parameter estimation method for pseudo-random binary phase code (PRBC) and linear frequency modulation (LFM) composite modulation signal in a complex electromagnetic environment. Firstly, this paper uses the square operation to remove the code phase information; secondly, we use the delay correlation and two times frequency estimation to estimate the starting frequency and the frequency modulation rate; finally, the wavelet transform algorithm is utilized to estimate the code rate parameter. Through the simulation analysis and full comparison with other methods, we can prove the performance superiority of this method under low signal-to-noise ratios (SNRs).

Enhanced Electrochromic Properties of Nanostructured WO3 Film by Combination of Chemical and Physical Methods

WO3 films are the most widely used electrochromic functional layers. It is known that WO3 films prepared by pure chemical method generally possess novel nanostructures, but the adhesion between WO3 films and substrates is weak. However, WO3 films prepared by pure physical method usually show relatively dense morphology, which limits their electrochromic properties. In order to break through these bottlenecks and further improve their electrochromic properties, this work first prepared nanostructured WO3 powder by chemical method, and then using this powder as the evaporation source, nanostructured WO3 films were fabricated by vacuum thermal evaporation method. Properties of nanostructured WO3 films were systematically compared with those of ordinary WO3 films. It turned out that the nanostructured WO3 film exhibited better cyclic stability and memory effect, and also the optical modulation rate was 14% higher than that of the ordinary WO3 film. More importantly, the nanostructured WO3 film showed better adhesion with the ITO substrates. These results demonstrate that a combination of chemical and physical methods is an effective preparation method to improve the electrochromic properties of WO3 films.

A specific relationship between musical sophistication and auditory working memory

Musical engagement may be associated with better listening skills, such as the perception of and working memory for notes, in addition to the appreciation of musical rules. The nature and extent of this association is controversial. In this study we assessed the relationship between musical engagement and both sound perception and working memory. We developed a task to measure auditory perception and working memory for sound using a behavioural measure for both, precision. We measured the correlation between these tasks and musical sophistication based on a validated measure (the Goldsmiths Musical Sophistication Index) that can be applied to populations of both musicians and non-musicians. The data show that musical sophistication accounts for 21% of the variance in the precision of working memory for frequency in an analysis that accounts for age and non-verbal intelligence. Musical sophistication was not significantly associated with the precision of working memory for amplitude modulation rate or with the precision of perception of either acoustic feature. The work supports a specific association between musical sophistication and working memory for sound frequency.

Development of a metric for predicting people's responses to gusting wind noise in automobiles

Automobile manufacturers are trying to improve the interior noise environment in their cars. A more thorough understanding of how people perceive the noise is an important step towards this goal. The focus of the current research is on modeling the acceptability of time-varying wind noises containing gusts. A listening test was designed containing sounds that were simulated on the computer, based on pre-defined airflow profiles. The time-varying noises in the test follow one of two simple gusting scenarios. The primary scenario contained two segments of steady wind flanking a series of consecutive equal-strength gusts. The number, duration, and strength of the gusts were varied between sounds. This was done to examine general trends of acceptability with modulation rate, modulation depth, and duration. The second scenario contained two gusts of equal or unequal strength, occurring either without a break or separated by a time gap. This was done to examine the relationship between people's reactions to the individual gusts in a pattern and their reactions to the whole pattern. A small number of steady-wind noises were included for reference. Terms in an acceptability model containing a previously proposed gusting metric were estimated. Possible refinements to the metric and model are discussed.

A specific relationship between musical sophistication and auditory working memory

Musical engagement may be associated with better listening skills, such as the perception of and working memory for notes, in addition to the appreciation of musical rules. The nature and extent of this association is controversial. In this study we assessed the relationship between musical engagement and both sound perception and working memory. We developed a task to measure auditory perception and working memory for sound using a behavioural measure for both, precision. We measured the correlation between these tasks and musical sophistication based on a validated measure (the Goldsmiths Musical Sophistication Index) that can be applied to populations of both musicians and non-musicians. The data show that musical sophistication accounts for 21% of the variance in the precision of working memory for frequency in an analysis that accounts for age and non-verbal intelligence. Musical sophistication was not significantly associated with the precision of working memory for amplitude modulation rate or with the precision of perception of either acoustic feature. The work supports a specific association between musical sophistication and working memory for sound frequency.

Optical Wireless Link Operated at the Wavelength of 4.0 µm with Commercially Available Interband Cascade Laser

This paper evaluates the key factors influencing the design of optical wireless communication (OWC) systems operating in the mid-infrared range. The performed analysis has shown that working in this spectral “window”, compared to other wavelengths, is more effective in reducing the attenuation of radiation. The main goal was to verify the capabilities of the “on-shelf” interband cascade (IC) laser in the context of OWC system construction, considering its output power, modulation rate, room temperature operation, and integrated structure. For this purpose, a lab model of a data link with IC laser has been developed. Based on its main parameters, the estimation of signal-to-noise power ratio versus data link range was made. That range was about 2 km for a case of low scintillation and relatively low visibility. In the experimental part of the work, the obtained modulation rate was 70 MHz for NRZ (non-return-to-zero) format coding. It is an outstanding result taking into consideration IC laser operated at room temperature.

Effects of Visual Speech Envelope on Audiovisual Speech Perception in Multitalker Listening Environments

Purpose This study investigated the effects of visually presented speech envelope information with various modulation rates and depths on audiovisual speech perception in noise. Method Forty adults (21.25 ± 1.45 years) participated in audiovisual sentence recognition measurements in noise. Target speech sentences were auditorily presented in multitalker babble noises at a −3 dB SNR. Acoustic amplitude envelopes of target signals were extracted through low-pass filters with different cutoff frequencies (4, 10, and 30 Hz) and a fixed modulation depth at 100% (Experiment 1) or extracted with various modulation depths (0%, 25%, 50%, 75%, and 100%) and a fixed 10-Hz modulation rate (Experiment 2). The extracted target envelopes were synchronized with the amplitude of a spherical-shaped ball and presented as visual stimuli. Subjects were instructed to attend to both auditory and visual stimuli of the target sentences and type down their answers. The sentence recognition accuracy was compared between audio-only and audiovisual conditions. Results In Experiment 1, a significant improvement in speech intelligibility was observed when the visual analog (a sphere) synced with the acoustic amplitude envelope modulated at a 10-Hz modulation rate compared to the audio-only condition. In Experiment 2, the visual analog with 75% modulation depth resulted in better audiovisual speech perception in noise compared to the other modulation depth conditions. Conclusion An abstract visual analog of acoustic amplitude envelopes can be efficiently delivered by the visual system and integrated online with auditory signals to enhance speech perception in noise, independent of particular articulation movements.

The Relationship between Psychoacoustic and Electrophysiological Assessments of Temporal Resolution

Background Temporal resolution is essential to speech acoustic perception. However, it may alter in individuals with auditory disorders, impairing the development of spoken and written language. The envelope of speech signals contains amplitude modulation (AM) that has critical information. Any problem reducing the listener's sensitivity to these amplitude variations (auditory temporal acuity) is likely to cause speech comprehension problems. The modulation detection threshold (MDT) test is a measure for evaluating temporal resolution. However, this test cannot be used for patients with poor cooperation; therefore, objective evaluation of MDT is essential. Purpose The main aim of this study is to find the association between the auditory steady-state response (ASSR) and psychoacoustic measurement of MDT at different intensity levels and to assess the amplitude and phase of ASSR as a function of modulation depth. Design This was a correlational research. Study Sample Eighteen individuals (nine males and nine females) with normal hearing sensitivity, aged between 18 and 23 years, participated in this study. Data Collection and Analysis ASSR was recorded at fixed AM rates and variable AM depths for carrier frequencies of 1,000 and 2,000 Hz with varying intensities. The least AM depth, efficient to evoke an ASSR response, was interpreted as the physiological detection threshold of AM. The ASSR amplitude and phase, as a function of AM depth, were also evaluated at an intensity level of 60 dB hearing level (HL) with modulation rates of 40 and 100 Hz. Moreover, the Natus instrument (Biologic Systems) was used for the electrophysiological measurements. An AC40 clinical audiometer (Intra-acoustic, Denmark) was also used for the psychoacoustic measurement of MDT in a similar setting to ASSR, using the two-alternative forced choice method. Pearson's correlation test and linear regression model and paired t-test were used for statistical analyses. Results A significant positive correlation was found between psychoacoustic and electrophysiological measurements at a carrier frequency of 1000 Hz, with a modulation rate of 40 Hz at intensity levels of 60 dB HL (r = 0.63, p = 0.004), 50 dB HL (r = 0.52, p = 0.02). A significant positive correlation was also found at a carrier frequency of 2000 Hz, with a modulation rate of 47 Hz at 60 dB HL (r = 0.55, p = 0.01) and 50 dB HL (r = 0.67, p = 0.002) and a modulation rate of 97 Hz at 60 dB HL (r = 0.65, p = 0.003). Moreover, a significant association was found between the modulation depth and ASSR amplitude and phase increment at carrier frequencies of 1,000 and 2000 Hz, with modulation rates of 40 and 100 Hz. Conclusion There was a significant correlation between ASSR and behavioral measurement of MDT, even at low intensities with low modulation rates of 40 and 47 Hz. The ASSR amplitude and phase increment was a function of modulation depth increase. The findings of this study can be used as a basis for evaluating the relationship between two approaches in the clinical population.