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Electronic nicotine delivery systems (ENDS) continue to rapidly evolve. Current products pose unique challenges and opportunities for researchers and regulators. This commentary aims to highlight research gaps, particularly in toxicity research, and provide guidance on priority research questions for the tobacco regulatory community. Disposable flavoured ENDS have become the most popular device class among youth and may contain higher nicotine levels than JUUL devices. They also exhibit enhanced harmful and potentially harmful constituents production, contain elevated levels of synthetic coolants and pose environmental concerns. Synthetic nicotine and flavour capsules are innovations that have recently enabled the circumvention of Food and Drug Administration oversight. Coil-less ENDS offer the promise of delivering fewer toxicants due to the absence of heating coils, but initial studies show that these products exhibit similar toxicological profiles compared with JUULs. Each of these topic areas requires further research to understand and mitigate their impact on human health, especially their risks to young users.

Background. The study of microalgae cultivation process is not only related to obtaining a wide range of biologically active substances. With the development of mariculture, some species of microalgae (including Chaetoceros muelleri) are of interest as food for mollusks, arthropods and holothuria. The aim of this study was to evaluate the effect of auxin hormones on quantitative and qualitative parameters Chaetoceros muelleri accumulative cultivation. Materials and methods. The object of research was the culture of microalgae Chaetoceros muelleri. The duration of the experiment was 7 days. Indole-3- butyric and indole-3-acetic acids were used for growth stimulation. The microalgae were cultured in monoculture, under constant conditions. 0.1; 0.2; 0.4; 0.6; 1.0 ×10-5mol phytohormones concentrations were added to the cultivation medium of the experimental groups. The control group was cultured without phytohormones addition. Results. It was shown that indole-3-acetic acid in concentrations from 0.2 to 0.5×10-5 mol had a positive effect on the growth of algal culture. Auxins at optimum concentration had a positive effect on lipid accumulation in the algal culture. It was found that indole-3-butyric acid increased the carbohydrate content in the culture on the 3rd day of culturing Chaetoceros muelleri. At the same time, under the action of indole-3-butyric acid, the highest content of carbohydrates. Conclusion. The obtained data showed that the studied auxins had a positive effect on Chaetoceros muelleri dynamics growth. The possibility of using auxin series phytohormones to stimulate the growth of the microalga Chaetoceros muelleri in an accumulative monoculture has been established by this study.

Purpose: experimental study and assessment of technical capabilities of a device for aerating the water bottom layers in reservoirs using solar radiation in Syrian conditions. Materials and methods. Empirical method was adopted as a research method. In accordance with the patent for a utility model, the experimental unit was a metal cylindrical body of a storage tank, in the lower part of which there was a fitting connected to a plastic air tube. Results. In the process of laboratory studies under conditions of different air temperatures, when assessing the capabilities of the unit, three characteristic periods of its operation were identified: intensive – a period with active air output lasting 110–120 minutes; transitional – with a gradual drop in intensity by more than half, lasting from 10 to 30 minutes; stable – a period with an almost uniform air output with a maximum observable duration of up to 60 minutes. An analysis of research materials showed that, depending on the daytime temperature, the air volume released during more than 180 minutes of observation was up to 7.6 liters. Moreover, in all experiments, more than 90 % of the air volume came out during the first 120 minutes, which should be considered as the period of active operation of the unit. Conclusions. Based on the results of experiments in an open area in the climatic conditions of Syria, the possibility of aerating natural reservoirs using a device for aerating bottom layers of water, the operation of which is based on the use of solar radiation without traditional energy sources, was proven.

Optoelectronic wear monitoring system of rotor blades of steam turbine low-pressure cylinders provide an assessment of the chord value of the working blade in static conditions on a closed cylinder. However, these systems do not allow the operator to assess the wear with the necessary error during shaft rotation. The control process is complicated by the fact that the output edge of the blade is overlapped by the input edge of the next blade; therefore it is necessary to set a scanning direction for each section that will ensure the formation of blade video frames, including both the input and output edges. The shaft rotation mode requires the use of pulsed illumination of the edges of the working blades to reduce the amount of image smudge; therefore it is necessary to select the focal length of the camera lens, the diameter of the entrance pupil of the lens and the power of pulsed radiation sources. The development of a methodology for selecting system parameters will help to reduce the complexity of designing systems for various turbine models and application technologies. Therefore, this is an important task. A methodology has been developed for selecting the parameters of the wear control systems of the working blades, which is based on the criterion of equality of the main components of the total error of the chord value. The analytical studies used the relationship of the parameters of the matrix receiver of optical radiation, illumination sources and the optical circuit with the required characteristics of the system. Computer modeling of the information conversion process in the system under study took into account the relationship between the parameters of the moving blades and the parameters of the optical circuit. The experimental estimation of the system error in statics and dynamics is based on multiple measurements after calibration of the system according to known parameters of the blades. When using the developed methodology, it is possible to achieve the required field of view and a given error in controlling the chord value, due to the choice of: matrix optical radiation receiver, focal length of the camera lens, diameter of the lens entrance pupil, and power of radiation sources. Using the example of the fifth stage of the vane device of the K-1200 high unit power turbine, which is most susceptible to wear, it is shown that for maximum values of the rotation angles of the video probe is 19° and the delay time of frame synchronization is up to 0.18 s, the focal length of the camera lens should be less than 2.4 mm with a pulse illumination time of 0.05 s. Computer modeling has shown that the marginal error of the system can reach 0.011 mm, which illustrates the possibility of reducing the total error. Using the developed methodology, the main elements were selected and a layout of the system was created. The requirements for exposure time and delay time of frame synchronization are formulated. The effectiveness of the parameter selection methodology was confirmed by experimental studies of the system layout, which showed that the estimate of the standard deviation of the random component of the chord control error in dynamics was 0.26 mm, which is three times less than that of the previously developed system and meets the requirements for evaluating the operability of the rotor blades of steam turbines during operation and repair. The proposed technique can be used by developers of other optoelectronic means of contactless control of linear dimensions of parts oriented non-perpendicular to the line of sight.

In this narrative review, we highlight the challenges of comparing emissions from different tobacco products under controlled laboratory settings (using smoking/ vaping machines). We focus on tobacco products that generate inhalable smoke or aerosol, such as cigarettes, cigars, hookah, electronic cigarettes, and heated tobacco products. We discuss challenges associated with sample generation including variability of smoking/vaping machines, lack of standardized adaptors that connect smoking/vaping machines to different tobacco products, puffing protocols that are not representative of actual use, and sample generation session length (minutes or number of puffs) that depends on product characteristics. We also discuss the challenges of physically characterizing and trapping emissions from products with different aerosol characteristics. Challenges to analytical method development are also covered, highlighting matrix effects, order of magnitude differences in analyte levels, and the necessity of tailored quality control/quality assurance measures. The review highlights two approaches in selecting emissions to monitor across products, one focusing on toxicants that were detected and quantified with optimized methods for combustible cigarettes, and the other looking for productspecific toxicants using non-targeted analysis. The challenges of data reporting and statistical analysis that allow meaningful comparison across products are also discussed. We end the review by highlighting that even if the technical challenges are overcome, emission comparison may obscure the absolute exposure from novel products if we only focus on relative exposure compared to combustible products.

Abstract Machine learning (ML) is widely used in classification tasks aimed at detecting various cognitive states or neurological diseases using noninvasive electroencephalogram (EEG) time series. However, successfully detecting specific cognitive skills in a healthy population, independent of subject, remains challenging. This study compared the subject-independent classification performance of three different pipelines: supervised and Riemann projections with logistic regression and handcrafted power spectral features with light gradient boosting machine (LightGBM). 128-channel EEGs were recorded from 26 healthy volunteers while they solved arithmetic, logical, and verbal tasks. The participants were divided into two groups based on their higher education and occupation: specialists in mathematics and humanities. The balanced accuracy of the education type was significantly above chance for all pipelines: 0.84–0.89, 0.85–0.88, and 0.86–0.88 for each type of task, respectively. All three pipelines allowed us to distinguish mathematical proficiency based on learning experience with different trade-offs between performance and explainability. Our results suggest that ML approaches could also be effective for recognizing individual cognitive traits using EEG.

TWIST1 (TW) is a pro‐oncogenic basic helix–loop–helix (bHLH) transcription factor and promotes the hallmark features of malignancy (e.g., cell invasion, cancer cell stemness, and treatment resistance), which contribute to poor prognoses of glioblastoma (GBM). We previously reported that specific TW dimerization motifs regulate unique cellular phenotypes in GBM. For example, the TW:E12 heterodimer increases periostin (POSTN) expression and promotes cell invasion. TW dimer‐specific transcriptional regulation requires binding to the regulatory E‐box consensus sequences, but alternative bHLH dimers that balance TW dimer activity in regulating pro‐oncogenic TW target genes are unknown. We leveraged the ENCODE DNase I hypersensitivity data to identify E‐box sites and tethered TW:E12 and TW:TW proteins to validate dimer binding to E‐boxes in vitro. Subsequently, TW knockdown revealed a novel TCF4:TCF12 bHLH dimer occupying the same TW E‐box site that, when expressed as a tethered TCF4:TCF12 dimer, markedly repressed POSTN expression and extended animal survival. These observations support TCF4:TCF12 as a novel dimer with tumor‐suppressor activity in GBM that functions in part through displacement of and/or competitive inhibition of pro‐oncogenic TW dimers at E‐box sites.

The paper presents the results of the sterlet sturgeon Acipenser ruthenus reintroduction into the Kama Reservoir (Perm Krai, Russia) by sterlet fry from hatcheries into the reservoir since 2001. The effectiveness of hatchery releases was evaluated by monitoring gillnet sampling 2014–2020. The results showed that the species was reported throughout entire Kama Reservoir, which contrasts with 1988–1994 data, when the species was registered only at the upper part of the reservoir near the Kama River mouth. The highest number and biomass values of catch per unit effort (CPUE) of the sterlet were found in submerged river channels – the deepest habitats with flow conditions which are close to the ecological requirements of the species. The distribution of the sterlet within the channel biotopes of the reservoir is defined by reduced variability. The biggest individuals and the widest size range of the sterlet were typical for the upper area of the reservoir and Chusovskoy Bay, which have the greatest flow. The smallest sizes were typical for fish from catches near the dam of the reservoir, which is consistent with the published data on the distribution of sterlet in reservoir conditions. The presented results may indicate the artificial formation of the sterlet stock in the Kama Reservoir maintained by hatchery releases. The revealed distribution of the sterlet in the reservoir determines the direction of further research on natural reproduction and thus formation of an artificially formed population. Also, future studies are required to assess the possibility of hybridization of the sterlet of artificial origin with natural populations of the species, since the low genetic diversity of the sterlet released into the Kama Reservoir which can lead to irreversible loss of genetic individuality of the natural stocks of the species in the catchment of upper course of the Kama River.

The article analyzes the influence of training based on combined (combining asynchronous and synchronous forms in one pedagogical technology) online discussions (OD) on the formation of reflexion of future engineers. The relevance of the problem is revealed. It is conditioned by toughening requirements to reflexive abilities and network communicative competences of modern technical specialists in the conditions of digitalization of education, networking and socio-technical transformation of engineering activity. The algorithm of realization and stage-role structure of asynchronous and synchronous OD are presented. The four-stage technology of pedagogical application of combined OD combining online-discussions with face-to-face reflexive classes is described, taking into account the mediated nature of learning in the digital environment and psychological features of future engineers related to the specifics of technical thinking. The methodological peculiarities (combination of online discussions with classroom training; stage-role differentiation of online discussions (structuring) on the basis of a scenario plan; use of a facilitation model with partially symmetric interaction of online discussions participants; conducting online discussions in microgroups of 4-6 hours) were identified and the mechanisms of their influence on the effectiveness of combined online discussions in the formation of future engineers’ reflexion were described. Taking into account the above mentioned methodological features, the teacher’s recommendations on the effective organization of the educational process in technical universities on the basis of the developed technology have been formulated. The correlation between the application of the developed technology and the improvement of the subjects’ reflexive skills by 19.67-32.79% was shown and a conclusion was made about its significant role in the formation of a holistic view of the students of technical universities about the discussion as a complex multidimensional category, in which an important role is played by building social interaction with opponents, understanding their position and reaching compromise solutions.

Abstract Increasing the population density of target species is a major goal of ecosystem and agricultural management. This task is especially challenging in hazardous environments with a high abundance of natural enemies such as parasites and predators. Safe locations with lower mortality have been long considered a beneficial factor in enhancing population survival, being a promising tool in commercial fish farming and restoration of threatened species. Here we challenge this opinion and revisit the role of behavior structuring in a hostile environment in shaping the population density. We build a mathematical model, where individuals are structured according to their defensive tactics against natural enemies. The model predicts that although each safe zone enhances the survival of an individual, for an insufficient number of such zones, the entire population experiences a greater overall mortality. This is a result of the interplay of emergent dynamical behavioral structuring and strong intraspecific competition for safe zones. Non-plastic structuring in individuals’ boldness reduces the mentioned negative effects. We demonstrate emergence of non-plastic behavioral structuring: the evolutionary branching of a monomorphic population into a dimorphic one with bold/shy strains. We apply our modelling approach to explore fish farming of salmonids in an environment infected by trematode parasites.

Abstract Next‐generation flexible electronics for healthcare applications require biocompatible flexible non‐volatile memory for data storage. Ultra‐thin ferroelectric hafnium oxide films offer great potential for flexible memories due to their potential flexibility and perfect compatibility with modern technologies. This study presents ultra‐flexible and stretchable memory devices based on 10‐nm‐thick Hf0.5Zr0.5O2 film fabricated by an innovative technology involving encapsulation of the devices in a biocompatible organic package. They exhibit high memory functionality (remanent polarization of 27 µC cm−2) and withstand extreme mechanical conditions, including folding in half, multiple bending up to 150 000 bending cycles as well as tension with loads up to 1.5 kg. Further, flexible devices are employed as a platform to elucidate the fundamental role of mechanical stress in ferroelectricity of hafnia both experimentally and theoretically. Direct in situ experiment demonstrates that in‐plane tension causes changes in spontaneous polarization, coercive voltage, permittivity, and conductivity. First‐principle calculations explain the role of mechanical stress in ferroelectric and dielectric properties of hafnia. In applications, this work establishes a foundation for the implementation of biocompatible, high‐performance flexible ferroelectric memory, and in the field of ferroelectric materials fundamentals, it provides insight into the critical role of the residual mechanical stress that is inevitably present in thin films.