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The paper presents an analysis of water-level control in a thermal power plant (TPP) steam separator. This control structure is vital for the entire plant’s stable, reliable, and efficient operation. This process belongs to processes with an integrator because it concerns a level-control issue, and the control variable is the feedwater flow. Said industrial processes are challenging to control and apply standard methods for tuning the PID controller, so a new procedure has been proposed. A procedure for tuning a PID controller for integrating processes is proposed based on the IFOPDT model, obtained from the wide step response of the process. Based on the process parameters estimated, the tuning of the controller is proposed. Results from the TPP TEKO-B2 (350 MW) are presented as an experimental verification. Compared with standard tuning methods, better results are achieved in the form of rise time and disturbance elimination rate. A significantly less risky and faster experiment for parameter estimation and controller tuning is also obtained. In addition, one adjustable parameter is provided to select the relation between performance and robustness. This method can be applied to various industrial processes with an integrator.

Mast cells (MCs) have been identified in various tumors; however, the role of these cells in tumorigenesis remains controversial. Here, we quantified MCs in human and murine malignant pleural effusions (MPEs) and evaluated the fate and function of these cells in MPE development. Evaluation of murine MPE-competent lung and colon adenocarcinomas revealed that these tumors actively attract and subsequently degranulate MCs in the pleural space by elaborating CCL2 and osteopontin. MCs were required for effusion development, as MPEs did not form in mice lacking MCs, and pleural infusion of MCs with MPE-incompetent cells promoted MPE formation. Once homed to the pleural space, MCs released tryptase AB1 and IL-1[beta], which in turn induced pleural vasculature leakiness and triggered NF-[kappa]B activation in pleural tumor cells, thereby fostering pleural fluid accumulation and tumor growth. Evaluation of human effusions revealed that MCs are elevated in MPEs compared with benign effusions. Moreover, MC abundance correlated with MPE formation in a human cancer cell-induced effusion model. Treatment of mice with the c-KIT inhibitor imatinib mesylate limited effusion precipitation by mouse and human adenocarcinoma cells. Together, the results of this study indicate that MCs are required for MPE formation and suggest that MC-dependent effusion formation is therapeutically addressable., Introduction Inflammation was recently recognized as an enabling hallmark of cancer that may mediate tumor growth and dissemination instead of tumor eradication (1). Inflammatory signaling networks in the tumor microenvironment [...]

In this paper, the influence of multiwalled carbon nanotubes (MWCNT) and carbon nanotubes modified with COOH groups (MWCNT-COOH) on the mechanical and electrical properties as well as on thermal stability of polyurethane (PU) were investigated. The samples of nanocomposite were prepared by dispersion of the nanofiller in a solution of polyurethane in acetone, followed by slow evaporation of the solvent at room temperature. The effect of the fillers on the mechanical properties of PU nanocomposites was examined by the uniaxial deformation test, and electrical properties of the samples were determined by the four probe method. Thermal stability was investigated by thermogravimetric analysis (TGA). The addition of both types of MWCNTs fillers increases modulus (Fig. 1), due to higher modulus of the nanofillers. Due to the better distribution in PU matrix and stronger interactions between COOH groups and carbonyl group in PU matrix, nanocomposites with MWCNT-COOH have higher modulus than nanocomposites with MWCNT filler. Most of the composites have lower strength and elongation at break than PU (Figs. 2 and 3). Smaller MWCNT-COOH aggregates and stronger interactions between this filler and the PU matrix cause less pronounced decreasing of strength at break. Compared to the pure PU, with conductivity of the order of 10−13 S cm−1, the conductivity of the nanocomposite with mass fraction of MWCNT nanofiller 0.2 % substantially increases up to the value of the order 10−6 S cm−1 (Fig. 4). A further increase up to 4 % for both types of MWCNTs, resulted in a further increase in conductivity up to values exceeding 10−2 S cm−1. Due to the better distribution in PU matrix and stronger interactions between COOH groups and carbonyl groups in PU matrix, the conductivity increase effect in systems with MWCNTs-COOH is slightly more pronounced. All investigated nanocomposites have potential applications as electric discharge materials and for electrostatic painting. The results of the thermogravimetric analysis indicate that the addition of both types of MWCNTs significantly improves the thermal stability (Figs. 6 and 7). The maximal degradation rate temperature of polyurethane increased by about 45 °C, thereby this effect is slightly more pronounced for systems with MWCNTs (Fig. 7). [ABSTRACT FROM AUTHOR]

In this work, the influence of multiwalled carbon nanotubes (MWCNT) and carbon nanotubes modified with COOH groups (MWCNT-COOH) on the structure and properties of thermoplastic polyurethane (PU) were investigated. The samples of nanocomposite were prepared from a mixture of polyurethane and MWCNT in acetone by slow drying at room temperature. The effect of the addition of nanofillers on the spherulite structure of polyurethane and the distribution of the nanofillers in the PU matrix were analysed with optical polarization microscopy. Thermal properties in non-isothermal and isothermal conditions were investigated by differential scanning calorimetry (DSC). The results of contact angle measurement imply that modification of MWCNT surface with COOH groups changes its surface from hydrophobic to hydrophilic (Fig. 2 and Table 1). Optical polarization microscopy showed that the addition of both nanofillers disrupts the coarse spherulite morphology of the polyurethane matrix (Fig. 4 and Fig. 5). It was observed that, at the macro level, the modified MWCNT-COOH filler is better distributed in the PU matrix than is the MWCNT filler (Fig. 5). The DSC results showed that, in non-isothermal conditions, up to a certain amount, both nanofillers accelerate the crystallization of the soft segments of polyurethane. This effect is more pronounced in systems with MWCNT filler (Fig. 9). The results of the crystallization enthalpy during cooling showed that MWCNT filler, despite its worse distribution in the PU matrix, more significantly enhances crystallization of PU’s soft segment than does the MWCNT-COOH filler (Fig. 10). This conclusion can be ascribed to better compatibility between the nonpolar MWCNT filler and the nonpolar soft phase of the PU matrix, as well as to the previous scientific finding that functional groups at MWCNT surface decrease the nucleation effect of MWCNT. By analysing the melting peaks, it can be concluded that the PU systems with MWCNT compared to systems with MWCNT-COOH contain a higher proportion of less ordered crystalline soft phase (Fig. 11). In isothermal conditions, the MWCNT filler accelerates crystallization more significantly than does the MWCNT-COOH filler (Fig. 16). [ABSTRACT FROM AUTHOR]

There is an increasing body of evidence suggesting that there are low-level perceptual processes involved in crossmodal correspondences. In this study, we investigate the involvement of the superior colliculi in three basic crossmodal correspondences: elevation/pitch, lightness/pitch, and size/pitch. Using a psychophysical design, we modulate visual input to the superior colliculus to test whether the superior colliculus is required for behavioural crossmodal congruency effects to manifest in an unspeeded multisensory discrimination task. In the elevation/pitch task, superior colliculus involvement is required for a behavioural elevation/pitch congruency effect to manifest in the task. In the lightness/pitch and size/pitch task, we observed a behavioural elevation/pitch congruency effect regardless of superior colliculus involvement. These results suggest that the elevation/pitch correspondence may be processed differently to other low-level crossmodal correspondences. The implications of a distributed model of crossmodal correspondence processing in the brain are discussed., (© 2024. The Author(s).)

The importance and interest in the efficient use and valorization of agro-industrial residues and by-products have grown due to environmental problems associated with improper disposal. Biotechnological production processes, including microbial biosurfactant production, represent a sustainable way to utilize agro-industrial residues and by-products, which are applied as substrates in these processes. Biosurfactants produced by microorganisms using renewable resources are a viable alternative to traditional petrochemical surfactants and have several potential uses in a wide range of industrial sectors due to their minimal ecotoxicity, easy biodegradability, and moderate production conditions. The common applications of biosurfactants, besides in food industry as food additives and preservatives, are in agriculture, environmental protection, the cosmetics and pharmaceutical industry, wastewater treatment, the petroleum industry, etc. This review aims to summarize the comprehensive scientific research related to the use of various agro-industrial residues and by-products in the microbial production of biosurfactants, as well as to emphasize the present state and the importance of their sustainable production. Additionally, based on the available biosurfactant market analysis datasets and research studies, the current situation in science and industry and the future perspectives of microbial biosurfactant production have been discussed.

In this research, the influence of titanium dioxide (TiO 2 ) nanoparticles and their modifications on the weathering resistance of untreated and heat-treated wood was studied. The wood samples were coated with polyacrylate waterborne emulsion coatings that contain nano-TiO 2 in the amount of 0.75 wt.%. Two types of modifiers were used to modify the nano-TiO 2 surface: 2,2'-azobis(2-methylpropionamide) dihydrochloride (AIBA) and 3-aminopropyltrimethoxy silane (AMPTS). Coated and uncoated wood samples were exposed to accelerated weathering by application of sunlight, water and moisture for 360 h. During the research, the dry film thickness, color, gloss and hardness of the surface of the samples were measured. The obtained results showed that the effect of the addition and surface modification of nano-TiO 2 on the color and gloss stability was different on untreated and heat-treated ash wood, and that accelerated weathering causes an increase in surface hardness and a decrease in thickness of the dry coating.

Stimulus statistics can induce expectations that in turn can influence multisensory perception. In three experiments, we manipulate perceptual history by biasing stimulus statistics and examined the effect of implicit expectations on the perceptual resolution of a bistable visual stimulus that is modulated by sound. First, we found a general effect of expectation such that responses were biased in line with the biased statistics and interpret this as a bias towards an implicitly expected outcome. Second, expectation did not influence the perception of all types of stimuli. In both Experiment 1 and Experiment 2, integrated audio-visual stimuli were affected by expectation but visual-only and unintegrated audio-visual stimuli were not. In Experiment 3 we examined the sensory versus interpretational effects of expectation and found that contrary to our predictions, an expectation of audio-visually integrated stimuli was associated with impaired multisensory integration compared to visual-only or unintegrated audio-visual stimuli. Our findings suggest that perceptual experience implicitly creates expectations that influence multisensory perception, which appear to be about perceptual outcomes rather than sensory stimuli. Finally, in the case of resolving perceptual ambiguity, the expectation effect is an effect on cognitive rather than sensory processes., (© 2022. Crown.)

The development of coatings that maintain the attractive natural appearance of wood while providing ultraviolet (UV) protection is extremely important for the widespread use of wood products. In this study, the influence of different types (powder form and aqueous dispersions) of TiO 2 in an amount of 1.0 wt% by monomer weight on the properties of environmentally friendly polyacrylate (PA)/TiO 2 emulsions prepared by ex situ and in situ polymerization, as well as on the UV-protective properties of the coating films, was investigated. The results showed that the addition of TiO 2 significantly affected the particle size distribution of PA and the viscosity of PA varied according to the preparation method. Compared with the ex situ preparation method, in situ polymerization provides better dispersibility of TiO 2 nanoparticles in PA coating film, as well as a better UV protection effect and greater transparency of the coating films. Better morphology and transparency of nanocoating films were achieved by adding TiO 2 nanofillers in aqueous dispersion as compared to the addition of TiO 2 in powder form. An increase in the glass transition temperature during UV exposure associated with cross-linking in the polymer was less pronounced in the in situ-prepared coating films, confirming better UV protection, while the photocatalytic effect of TiO 2 was more pronounced in the ex situ-prepared coating films. The results indicate that the method of preparation has a significant influence on the properties of the coating films.

We examine whether crossmodal correspondences (CMCs) modulate perceptual disambiguation by considering the influence of lightness/pitch congruency on the perceptual resolution of the Rubin face/vase (RFV). We randomly paired a black-and-white RFV (black faces and white vase, or vice versa) with either a high or low pitch tone and found that CMC congruency biases the dominant visual percept. The perceptual option that was CMC-congruent with the tone (white/high pitch or black/low pitch) was reported significantly more often than the perceptual option CMC-incongruent with the tone (white/low pitch or black/high pitch). However, the effect was only observed for stimuli presented for longer and not shorter durations suggesting a perceptual effect rather than a response bias, and moreover, we infer an effect on perceptual reversals rather than initial percepts. We found that the CMC congruency effect for longer-duration stimuli only occurred after prior exposure to the stimuli of several minutes, suggesting that the CMC congruency develops over time. These findings extend the observed effects of CMCs from relatively low-level feature-based effects to higher-level object-based perceptual effects (specifically, resolving ambiguity) and demonstrate that an entirely new category of crossmodal factors (CMC congruency) influence perceptual disambiguation in bistability.

We examine perceptual disambiguation and crossmodal interactions by considering the effect of recent perceptual history on stream-bounce perception. First, we tested the assumption that the audio-visual stream-bounce effect (visual-only trials mostly stream, whereas audio-visual trials mostly bounce) reflects some intrinsic preference for streaming that is broken by sound. Instead, we found that for naïve observers, visual-only stimuli are bistable and bias free. In intermixed trials, sound acts as a polarizing factor (rather than a bounce-inducing factor) and has as much effect on visual-only trials as it does on audio-visual trials. Second, temporal context exerts a comparative influence and exposure to audio-visual stimuli influences responses to visual-only stimuli and vice-versa. Finally, there is a serial dependence in responses and the current stimulus (unisensory or multisensory) is interpreted with a bias to recent interpretations. Recent perceptual history exerts a substantial influence on the perception of stream-bounce stimuli. This influence occurs in the unisensory case and is in line with an extensive literature on visual bistability; it extends to the multisensory case, and there are interactions between the 2 cases. Our combined findings support a role for top-down interpretational influences in the stream-bounce effect and stream-bounce perception more generally. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

We tested the sensory versus decisional origins of two established audiovisual crossmodal correspondences (CMCs; lightness/pitch and elevation/pitch), applying a signal discrimination paradigm to low-level stimulus features and controlling for attentional cueing. An audiovisual stimulus randomly varied along two visual dimensions (lightness: black/white; elevation: high/low) and one auditory dimension (pitch: high/low), and participants discriminated either only lightness, only elevation, or both lightness and elevation. The discrimination task and the stimulus duration varied between subjects. To investigate the influence of crossmodal congruency, we considered the effect of each CMC (lightness/pitch and elevation/pitch) on the sensitivity and criterion of each discrimination as a function of stimulus duration. There were three main findings. First, discrimination sensitivity was significantly higher for visual targets paired congruently (compared with incongruently) with tones while criterion was unaffected. Second, the sensitivity increase occurred for all stimulus durations, ruling out attentional cueing effects. Third, the sensitivity increase was feature specific such that only the CMC that related to the feature being discriminated influenced sensitivity (i.e. lightness congruency only influenced lightness discrimination and elevation congruency only influenced elevation discrimination in the single and dual task conditions). We suggest that these congruency effects reflect low-level sensory processes.

Previous research suggests that cognitive factors acting in a top-down manner influence the perceptual interpretation of ambiguous stimuli. To examine the temporal unfolding of these influences as a perceptual decision evolves, we have implemented a modified version of the stream-bounce display. Our novel approach allows us to track responses to stream-bounce stimuli dynamically over the entire course of the motion sequence rather than collecting a subjective report after the fact. Using a trackpad, we had participants control a cursor to track a stream-bounce target actively from start to end and measured tracking speed throughout as the dependent variable. Our paradigm replicated the typical effect of visual-only displays being associated with a streaming bias and audiovisual displays with a bouncing bias. Our main finding is a significant behavioral change preceding a perceptual decision that then predicts that decision. Specifically, for trials in which the sound was presented, tracking speeds were significantly slower starting 500 ms before the point of coincidence and presentation of the sound for bounce compared to stream responses. We suggest that behavioral response may reflect a cognitive expectation of a perceptual outcome that then biases action and the interpretation of sensory input to favor that forthcoming percept in a manner consistent with both the predictive-coding and common-coding theoretical frameworks. Our approach provides a novel behavioral corroboration of recent imaging studies that are suggestive of early brain activity in perception and action.

Aortic valve stenosis is the most common cardiac valve disease, and with current trends in the population demographics, its prevalence is likely to rise, thus posing a major health and economic burden facing the worldwide societies. Over the past decade, it has become more than clear that our traditional genetic views do not sufficiently explain the well-known link between AS, proatherogenic risk factors, flow-induced mechanical forces, and disease-prone environmental influences. Recent breakthroughs in the field of epigenetics offer us a new perspective on gene regulation, which has broadened our perspective on etiology of aortic stenosis and other aortic valve diseases. Since all known epigenetic marks are potentially reversible this perspective is especially exciting given the potential for development of successful and non-invasive therapeutic intervention and reprogramming of cells at the epigenetic level even in the early stages of disease progression. This review will examine the known relationships between four major epigenetic mechanisms: DNA methylation, posttranslational histone modification, ATP-dependent chromatin remodeling, and non-coding regulatory RNAs, and initiation and progression of AS. Numerous profiling and functional studies indicate that they could contribute to endothelial dysfunctions, disease-prone activation of monocyte-macrophage and circulatory osteoprogenitor cells and activation and osteogenic transdifferentiation of aortic valve interstitial cells, thus leading to valvular inflammation, fibrosis, and calcification, and to pressure overload-induced maladaptive myocardial remodeling and left ventricular hypertrophy. This is especcialy the case for small non-coding microRNAs but was also, although in a smaller scale, convincingly demonstrated for other members of cellular epigenome landscape. Equally important, and clinically most relevant, the reported data indicate that epigenetic marks, particularly certain microRNA signatures, could represent useful non-invasive biomarkers that reflect the disease progression and patients prognosis for recovery after the valve replacement surgery.

The audiovisual stream-bounce effect refers to the resolution of ambiguous motion sequences as streaming or bouncing depending on the presence or absence of a sound. We used a novel experimental design and signal detection theory (SDT) to determine its sensory or decisional origins. To account for issues raised by Witt et al. on the interpretation of SDT results, we devised a pure signal detection (as opposed to signal discrimination) paradigm and measured participants' sensitivity and criterion when detecting a weak tone concurrent with objectively streaming or bouncing visual displays. We observed no change in sensitivity but a significant change in criterion with participants' criterion more liberal with bouncing targets than for streaming targets with. In a second experiment, we tasked participants with detecting a weak tone in noise while viewing an ambiguous motion sequence. They also indicated whether the targets appeared to stream or bounce. Participants' reported equivalent, mostly bouncing responses for hit and false alarm trials, and equivalent, mostly streaming responses for correct rejection and miss trials. Further, differences in participants' sensitivity and criterion measures for detecting tones in subjectively streaming compared to subjectively bouncing targets were inconsistent with sensory factors. These results support a decisional account of the sound-induced switch from mostly streaming to mostly bouncing responses in audiovisual stream-bounce displays.

The stream-bounce effect refers to a bistable motion stimulus that is interpreted as two targets either "streaming" past or "bouncing" off one another, and the manipulations that bias responses. Directional bias, according to Bertenthal et al., is an account of the effect proposing that low-level motion integration promotes streaming, and its disruption leads to bouncing, and it is sometimes cited either directly in a bottom-up fashion or indirectly under top-down control despite Sekuler and Sekuler finding evidence inconsistent with it. We tested two key aspects of the hypothesis: (a) comparable changes in speed should produce comparable disruptions and lead to similar effects; and (b) speed changes alone should disrupt integration without the need for additional more complex changes of motion. We found that target motion influences stream-bounce perception, but not as directional bias predicts. Our results support Sekuler and Sekuler and argue against the low-level motion signals driving perceptual outcomes in stream-bounce displays (directly or indirectly) and point to higher level inferential processes involving perceptual history and expectation. Directional bias as a mechanism should be abandoned and either another specific bottom-up process must be proposed and tested or consideration should be given to top-down factors alone driving the effect.

Objective: Objective of our study was to evaluate changes in Doppler resistance indices in the common hepatic artery during normal pregnancy., Study Design: Cross-sectional study included 210 healthy pregnant women gestational age 6-40 weeks, 40 healthy non-pregnant women and 30 women after delivery. We divided all pregnant women by pregnancy trimester. We registered pulsatility index (PI) and resistive index (RI) in the common hepatic artery and compared the evaluated values among non-pregnant women and women in first, second and third trimester and post partum and tested correlation of both parameters with gestational age. Statistical analysis was done by Chi square test, one-way ANOVA followed by post-hoc test and two-tailed Pearson and Spearman correlation. The difference was considered to be significant if p<0.05., Results: We found lower values of PI and RI in the third trimester compared to control group and first and second trimester (p<0.01). There is negative correlation between the values of PI and RI with the gestation (p<0.01)., Conclusion: Hepatic artery resistance indices decrease during the third trimester of pregnancy. This decrease may be the result of systemic arterial vasodilatation in normal pregnancy. The arterial resistance indices may be more useful for the evaluation of liver blood flow over the total blood flow as they are more reliable, being angle independent, easier to obtain, reflect vascular changes and might help in quick orientation about liver blood flow in pregnancies complicated by preeclampsia and HELLP syndrome. Our study is a pilot one, and further studies are needed to establish nomograms for the PI and RI during the gestation., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)