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Studies on recycled materials emerged during recent years. This paper investigates the properties of sound absorption and transmission loss of the structures of the perforated plastic panel (PPP) backed with the rubber granule panel (RGP). Under production conditions, such a structure could be produced using only waste. The normal incidence sound absorption and transmission loss of the structure was measured using ISO 10534-2 and ASTM E2611-17 standard methods, respectively. In this study, the plastic panel perforation holes were tilted in steps of 15°–45° compared to the vertical axis of the sample. Different thickness rubber panels were used as backing (12 mm, 22 mm and 27 mm). The results showed that the sound absorption and transmission loss increased with the angle of the perforation pore. To compare the different structures, the multi-criteria analysis using the technique for order of preference by similarity to ideal solution (TOPSIS) approach was done. The RGP thickness, sound absorption coefficient (SAC) and sound transmission loss (STL) were weighted as a criterion. The results of the multi-criteria analysis showed that the optimal structure for a possible application is PPP45°+ RGP 22 mm, which was ranked highest of all alternatives. The first peak of SAC reached 0.97 at 1000 Hz. In the frequency range of 250–1000 Hz, STL values reached up to 10.4 dB and in the frequency range of 1–4 kHz – 20.1 dB. The results obtained using RGP and PPP show promising development potential for sound absorption and insulation applications.

Rigid polyurethane (PU) foams were modified with rowanberry/vermiculite fillers. The impact of fillers on selected properties of composites, such as rheological properties (dynamic viscosity, foaming behavior), mechanical properties (compressive and flexural strength, toughness), thermal properties (temperature of thermal decomposition stages, char residues at 600°C), flame retardancy (ignition time IT, total heat, and smoke release THR and TSR, maximum average rate of heat emission MARHE) was investigated. The results show that the incorporation of rowanberry/vermiculite fillers improves the properties of polyurethane foams. For instance, compared with the reference foam, modified foams showed increased synthesis times and higher values of apparent density, which then influenced the mechanical properties. Compared to the unmodified foam, modified foams showed an improvement in compressive strength (up to 7.8%, measured parallel to the foam growth direction), flexural strength (up to 5.8%), and toughness (up to 6.8%). Most importantly, the modified foams showed improved thermal stability and flammability parameters such as elongated ignition time, lowered values of THR, TSR, and MARHE parameters.

Aim. It has been established by research that learners’ approaches to learning and to the learning contexts in which it occurs play a pivotal role at all levels of education. Tertiary students’ approaches to learning have been widely investigated across different fields of study, however, little known research has focused on their approaches to learning foreign languages. Thus, to deepen our understanding in this field, the present research aims at establishing undergraduate students’ approaches to learning English for Specific Purposes (ESP) in an institution of higher education in Lithuania. Methods. The investigation was conducted with the participation of 111 undergraduate students, majors in 11 different study programmes, who took a mandatory course in ESP. The data were collected from the structured questionnaires; to carry out the research, quantitative research methods were used. Results. The research revealed that some students’ low engagement in the study process and their intention to learn as much as to get a passing grade showed that they used surface approach to learning ESP. The findings also disclosed a positive correlation between the students’ organised and systematic learning and planning their study time, which led to the assumption that these students were likely to use a deep approach to learning ESP. Finally, the statistical calculations proved that the students, whose approach to learning ESP was deep, were able to self-regulate their learning. Conclusion. The main conclusion of this research is that the participants’ approaches to learning ESP were both surface and deep. The results also suggested that some students could be directed towards deep learning by fostering their engagement in the study activities.

The full-wave analysis was applied for a coaxial line (i.e., transmission line) that has a "short-circuited" discontinuity. The discontinuity has a radius less than or equal to the inner radius of the coaxial line. The "sample region" can be considered as a partially filled circular waveguide. Such a structure is very practical and is of particular interest for the dielectric spectroscopy applications. It takes into account the inhomogeneous field distribution, which is the limiting factor for the determination of high dielectric permittivity values at microwave frequencies. The direct problem was solved by using the mode-matching technique, and the relationship between the complex reflection coefficient and the dielectric permittivity of the cylindrical sample was obtained. By solving the inverse problem, it is possible to obtain the complex dielectric permittivity from the experimental values of the scattering matrix. The results were verified by the finite element modeling of the system and applied for particular materials. The correspondence between these approaches is excellent. This method is very suitable for the determination of permittivity, which exceeds several thousands (it is applicable for any type of material). It extends the frequency range where the permittivity can be determined reliably. There is no necessity to prepare samples with different geometries (i.e., surface area and thickness).

A short Edgeworth expansion is approximated for the distribution function of a Studentized linear combination of order statistics computed on a random sample drawn without replacement from a finite population, and using auxiliary data available for the population units. Simulations show an improvement over the usual Gaussian approximation and previous empirical Edgeworth expansions. Naive synthetic estimates of the distribution function, based on the auxiliary data only, yield accurate results when the auxiliary variable is well correlated with the study variable.

Background: The purpose of this study was to evaluate the circadian variation of human milk macronutrients and energy content depending upon pregnancy duration. Methods: One hundred eighty fresh human milk samples from 45 mothers (27 of preterm and 18 of full-term newborns) were collected on a single day chosen between the 14th to 16th day after delivery. The samples were taken four times per day at 12 PM, 6 PM, 12 AM and 6 AM. Only lactating women, who could not breastfeed their hospitalized newborns and expressed milk by breast pump, were enrolled in the study. Human milk macronutrient composition and energy count were evaluated by mid-infrared spectrophotometry. Results: Significant differences in macronutrient content were observed between 6 AM and 12 PM for mean protein content (t = - 4.62, df = 44, p < 0.001), for mean fat content (t = - 2.10, df = 44, p = 0.04) and for mean energy content (t = - 2.24, df = 44, p = 0.03); between 6 AM and 6 PM for mean protein content (t = - 2.41, df = 43, p = 0.02), for mean fat content (t = - 3.76, df = 43, p = 0.001) and for mean energy content (t = - 3.85, df = 43, p < 0.001); between 12 PM and 12 AM for mean protein content (Wilcoxon test V = 75.5, p = 0.001), for mean fat content (t = 2.50, df = 44, p = 0.02) and for mean energy content (t = 2.74, df = 44, p = 0.01); between 6 PM and 12 AM for mean protein content (V = 229, p = 0.02), for mean fat content (t = 4.39, df = 43, p < 0.001) and for mean energy content (t = - 4.57, df = 43, p < 0.001). The average content of carbohydrates did not change significantly during the 24 h. The samples of preterm newborns' mothers had more apparent diurnal fluctuations in macronutrient content. Conclusions: Our study revealed significant diurnal variations in protein and fat in human milk, and these circadian fluctuations were more apparent in the milk of mothers of preterm infants.

Emotion recognition from facial expressions has gained much interest over the last few decades. In the literature, the common approach, used for facial emotion recognition (FER), consists of these steps: image pre-processing, face detection, facial feature extraction, and facial expression classification (recognition). We have developed a method for FER that is absolutely different from this common approach. Our method is based on the dimensional model of emotions as well as on using the kriging predictor of Fractional Brownian Vector Field. The classification problem, related to the recognition of facial emotions, is formulated and solved. The relationship of different emotions is estimated by expert psychologists by putting different emotions as the points on the plane. The goal is to get an estimate of a new picture emotion on the plane by kriging and determine which emotion, identified by psychologists, is the closest one. Seven basic emotions (Joy, Sadness, Surprise, Disgust, Anger, Fear, and Neutral) have been chosen. The accuracy of classification into seven classes has been obtained approximately 50%, if we make a decision on the basis of the closest basic emotion. It has been ascertained that the kriging predictor is suitable for facial emotion recognition in the case of small sets of pictures. More sophisticated classification strategies may increase the accuracy, when grouping of the basic emotions is applied.

Straipsnyje šiuolaikinio įsivaizduojamybės diskurso kontekste nagrinėjamas Vileišių rūmų ansamblis – bene svarbiausias modernios lietuvybės istoriją Vilniuje ženklinantis architektūrinis objektas. Ansamblis apmąstomas kaip vietovaizdis, kurio vietą nacionalinėje vaizduotėje lemia dalyvavimas masinėje komunikacijoje ir aparatinių vaizdų prodiusavime, kaupime bei sklaidoje. Tyrime išryškinama, kad vietovaizdžio vaizdinija aktyvuoja savumo, pasididžiavimo, nostalgijos efektus, tačiau nepanaikina ir nežinomybės, neapibrėžtumo būsenų. Aptikti Vileišių rezidencijos simbolinės ir energetinės sistemos nesandarumai, prieštaringumai panaudojami kritiniam vietovaizdžio įsivaizdavimui, pagrįstam reprezentacijos stokos ir nepakankamumo konfigūravimu. Toks vaizduotės įvykis įgyvendinamas skirtingus vaizdinius elementus, rastus rūmų vaizdų archyvo tyrimo metu, susiejant tarpusavyje, juos animuojant ir montuojant kino medijoje. Dviejų projekcijų filmas „Drumsti skaidrumai“ rekonstruoja nacionalinio vietovaizdžio reprezentacijos pėdsakus ir medijuoja jų neapibrėžtumus, kartu steigdamas įsivaizduojamybę išlaisvinančią meno kūrinio erdvę. Derinant tiek menotyrinio ir meninio tyrimo, tiek ir šiuolaikinio meno prieigas permąstomos ansamblio – politinės teritorijos simbolio ir jo užsakovo – tautinio pasakojimo personažo reikšmės transnacionaliniame kontekste.

This paper sets a framework for using semiotics as an analytical method for Earth system science. It illustrates the use of such a method by analysing a dataset consisting of 32,383 abstracts of research articles pertaining to Earth system science, modelled as semantic networks. The analysis allows us to explain the epistemological advantages of this method as originating in the systems thinking common in both Earth system science and semiotics. The purpose of this methodological proposal is that of bringing the recent and critical planetary boundaries framework to the attention of ecosemiotics and biosemiotic criticism, and vice versa. Ecosemiotics is a branch of the biosemiotic modelling theory and is thus grounded in Charles Peirce’s schematic semiotics, but also developed in inspiration of Juri Lotman’s systemic semiotics. Both of these foundations of ecosemiotics are compatible with the rationale of Earth system science, given the schematism of Peirce’s semiotics and Lotman’s notion of meaning as an affordance of the biosphere. Far from exhausting the hermeneutic possibilities evoked by the discussed dataset, we argue that such semiotic analysis, made possible by the digital capacity of modelling large amounts of data, reveals new horizons for semiotic analysis, particularly regarding humans’ modelling of the environment.

Objectives: This study aims to investigate the distribution of myeloid-derived suppressor cells (MDSCs) in patients with primary or secondary Sjögren’s syndrome (SS) or rheumatoid arthritis (RA) in order to better understand MDSCs significance in the pathogenesis of these autoimmune diseases. Patients and methods: We examined the frequency and calculated absolute counts of overall MDSCs (human leukocyte antigen-antigen D related (HLA-DR)low/cluster of differentiation (CD) 33+/CD11b+) and monocytic MDSCs (HLA-DRlow/CD33+/CD11b+/CD14+) subset in peripheral blood samples of 23 RA (5 males, 18 females; mean age 57 years; range 41 to 81 years), 25 primary Sjögren’s syndrome (pSS) (1 male, 24 females; mean age 56 years; range 32 to 77 years), 17 secondary Sjögren’s syndrome (sSS) (1 male, 16 females; mean age 60 years; range 49 to 73 years) and 23 nonautoimmune sicca syndrome (nSS) (23 females; mean age 59 years; range 44 to 92 years) patients by flow cytometric analysis. Results: Analysis revealed that the frequency of overall MDSCs increased in RA group (46.5±3.4) compared with nSS group (35.6±3.2; p=0.0322). An increase of absolute count of overall MDSCs was most evident in both RA (4383±456.8) and sSS groups (3890±495.7) compared with pSS (2447±275.1; p=0.0002 and 0.0067) and nSS groups (2025±218.1; p<0.0001 and p=0.0012). The highest absolute count of monocytic MDSCs also manifested in RA group (195.4±39.0), compared with all the other groups (86.0±24.9; p=0.0002 [pSS], 128.5±53.4; p=0.0076 [sSS], 83.7±19.0; p=0.0136 [nSS]). Conclusion: To summarize, we have determined that the most prominent increase of both total and monocytic MDSCs was evident in RA and sSS groups, which leads us to believe that MDSCs are associated with rheumatic processes.