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It is essential to understand how teachers cope with stress and how this affects their well-being as teachers work in very demanding environments. The study employed the transactional model of stress and coping as a theoretical framework to investigate the relationship between the Psychological Capital dimensions (self-efficacy, hope, resilience, and optimism), future-oriented coping (proactive and preventive coping), and work-related well-being (job satisfaction and work engagement). An online survey was completed by 213 secondary school teachers in Germany. Multiple hierarchical regression analyses indicated that optimism and self-efficacy were significant predictors of proactive coping, and hope predicted preventive coping. Optimism, hope, and resilience had a significant impact on job satisfaction. Furthermore, hope, optimism, and proactive coping significantly predicted work engagement. Proactive coping mediated the relationship between teachers' self-efficacy and work engagement as well as between optimism and work engagement, whereas preventive coping was not a significant mediator. The results imply that developing the Psychological Capital dimensions and proactive coping through interventions can be a valuable avenue to increase teacher well-being.

Background: Percutaneous image-guided tissue ablation (IGA) plays a growing role in the clinical management of solid malignancies. Electroporation is used for IGA in several modalities: irreversible electroporation (IRE), and reversible electroporation with chemotoxic drugs, called electrochemotherapy (ECT). It was shown that the combination of electrolysis and electroporation-E2-affords tissue ablation with greater efficiency, that is, lower voltages, lower energy and shorter procedure times than IRE and without the need for chemotoxic additives as in ECT. Methods: A new E2 waveform was designed that delivers optimal doses of electroporation and electrolysis in a single waveform. A series of experiments were performed in the liver of pigs to evaluate E2 in the context of clinical applications. The goal was to find initial parameter boundaries in terms of electrical field, pulse duration and charge as well as tissue behavior to enable real time tissue ablation of clinically relevant volumes. Results: Histological results show that a single several hundred millisecond long E2 waveform can ablate large volume of tissue at relatively low voltages while preserving the integrity of large blood vessels and lumen structures in the ablation zone without the use of chemotoxic drugs or paralyzing drugs during anesthesia. This could translate clinically into much shorter treatment times and ease of use compared to other techniques that are currently applied.

The effects of organic modifiers—alcohols (methanol, isopropanol), acetonitrile, and tetrahydrofuran—and β-cyclodextrins in capillary zone electrophoresis were investigated using a test mixture containing five biogenic amines important from the human health point of view—serotonin, dopamine, adrenaline, noradrenaline, and tyramine—and two B vitamins—thiamine and pyridoxine. The simultaneous addition of tetrahydrofuran and isopropanol was found to improve the resolution of determined analytes and enable effective separation of analytes with very similar electromigration characteristics migrating as one peak (dopamine and serotonin). The developed and optimised separation method based on capillary zone electrophoresis and ultraviolet detection was capable to achieve detection limits at the concentration level in the range of 0.15 to 1.25 μg/mL−1. The developed method was also characterised by other favourable validation parameters, such as linearity (r2 > 0.99), accuracy (82.9–117.8% for the intraday measurements, and 87.6–119.2% for the interday measurements), and precision (intraday relative standard deviation in the range of 0.4–15.5%, interday relative standard deviation in the range of 0.9–18.3%). The method was finally applied to investigate the stability of the analytes in model water matrix samples under various storage conditions.

A prominent explanation of intergenerational educational inequality is Bourdieu's cultural reproduction theory. Indeed, previous studies have frequently shown that children's cultural capital relates to academic outcomes. However, it remains unclear how children convert their cultural capital into achievement. While Bourdieu argued that cultural capital influences academic outcomes primarily by biasing teachers' grades, other researchers have proposed the alternative explanation that children's cultural capital absorption directly translates into academic skills. Using survey data on 2975 fifth graders from the German National Educational Panel Study, we disentangle these two mechanisms of children's cultural capital conversion; and argue that the main conversion mechanism depends on the cultural capital dimension examined. The results of our structural equation model suggest that both mechanisms are at work and that the main conversion mechanism depends on the dimension of cultural capital examined.

The application of hydrodynamically closed capillary zone electrophoresis combined with convenient ultraviolet (UV) detection allows fast, simple, environmentally friendly and cost-effective analysis of ions or ionisable molecules. This technique has been used to determine two selected B vitamins (thiamine, pyridoxine) in various drug formulations. The developed method was characterised by excellent validation parameters, such as linearity, precision, accuracy, limit of detection and limit of quantification. The total time of analysis was lower than 13.5 min. The results indicate that the method is suitable for implementation in routine quality control of selected B vitamins in pharmaceutical and food samples.

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Managing energy in batteryless Internet of Things (IoT) nodes, especially in solar-powered mesh networks, presents significant challenges. This paper introduces an advanced solar irradiance model that simulates detailed daily energy profiles. The model considers various azimuth and elevation angles of solar panels, as well as cloud cover. Accurate simulation of daily energy production is critical for optimising the behaviour of solar-powered IoT nodes. The results highlight the utility of the model as a robust tool for research and simulations involving batteryless IoT devices, emphasising its enhanced capabilities for precise energy management and optimisation. This study offers a reliable framework for predicting and managing energy production in solar-powered IoT networks, thus supporting the development of more efficient and sustainable IoT systems. [ABSTRACT FROM AUTHOR]

BackgroundElectrolytic ablation and electroporation based ablation are minimally invasive, non-thermal surgical technologies that employ electrical currents and electric fields to ablate undesirable cells in a volume of tissue. In this study, we explore the attributes of a new tissue ablation technology that simultaneously delivers a synergistic combination of electroporation and electrolysis (E2).MethodA new device that delivers a controlled dose of electroporation field and electrolysis currents in the form of a single exponential decay waveform (EDW) was applied to the pig liver, and the effect of various parameters on the extent of tissue ablation was examined with histology.ResultsHistological analysis shows that E2 delivered as EDW can produce tissue ablation in volumes of clinical significance, using electrical and temporal parameters which, if used in electroporation or electrolysis separately, cannot ablate the tissue.DiscussionThe E2 combination has advantages over the three basic technologies of non-thermal ablation: electrolytic ablation, electrochemical ablation (reversible electroporation with injection of drugs) and irreversible electroporation. E2 ablates clinically relevant volumes of tissue in a shorter period of time than electrolysis and electroporation, without the need to inject drugs as in reversible electroporation or use paralyzing anesthesia as in irreversible electroporation.

A new minimally invasive tissue ablation technique, that combines the biophysical processes of electroporation and electrolysis, is introduced. The technology employs electrode needles inserted in the target tissue to deliver an Electrolytic Electroporation Waveform (EEW) in the form of an exponential decay voltage, several tens of microsecond long. A case study in a large animal model demonstrates that clinically significant size lesions can be achieved with a single, milliseconds long EEW. Ablation with EEW has major advantages over the comparable tissue ablation techniques of electrolysis, reversible electroporation and irreversible electroporation. EEW is orders of magnitude faster than conventional electrolytic ablation. EEW does not require the use of muscle relaxant as irreversible electroporation and EEW does not require injection of drugs as reversible electroporation. This new technology is simple to use and may become an important addition to the minimally invasive surgery armamentarium.

Nonthermal irreversible electroporation is a new tissue ablation technique that consists of applying pulsed electric fields across cells to induce cell death by creating permanent defects in the cell membrane. Nonthermal irreversible electroporation is of interest because it allows treatment near sensitive tissue structures such as blood vessels and nerves. Two recent articles report that electrolytic reaction products at electrodes can be combined with electroporation pulses to augment and optimize tissue ablation. Those articles triggered a concern that the results of earlier studies on nonthermal irreversible electroporation may have been tainted by unaccounted for electrolytic effects. The goal of this study was to reexamine previous studies on nonthermal irreversible electroporation in the context of these articles. The study shows that the results from some of the earlier studies on nonthermal irreversible electroporation were affected by unaccounted for electrolysis, in particular the research with cells in cuvettes. It also shows that tissue ablation ascribed in the past to irreversible electroporation is actually caused by at least 3 different cytotoxic effects: irreversible electroporation without electrolysis, irreversible electroporation combined with electrolysis, and reversible electroporation combined with electrolysis. These different mechanisms may affect cell and tissue ablation in different ways, and the effects may depend on various clinical parameters such as the polarity of the electrodes, the charge delivered (voltage, number, and length of pulses), and the distance of the target tissue from the electrodes. Current clinical protocols employ ever-increasing numbers of electroporation pulses to values that are now an order of magnitude larger than those used in our first fundamental nonthermal irreversible electroporation studies in tissues. The different mechanisms of cell death, and the effect of the clinical parameters on the mechanisms may explain discrepancies between results of different clinical studies and should be taken into consideration in the design of optimal electroporation ablation protocols.

This study is the first experimental evidence showing that a living multicellular organism, the nematode Caenorhabditis elegans, can survive subfreezing temperatures in an isochoric (constant volume) thermodynamic system, while immersed in a simple isotonic solution, without the addition of cryoprotectants. Some of the test conditions were more extreme than those found at the ice/water interface of the Antarctic subglacial Vostok lake. On earth, life takes place in an isobaric (constant pressure) environment. In isobaric systems, subfreezing temperature survival of organisms in nature and subfreezing temperature preservation of living material for biotechnology and medicine, is made possible by use of cryoprotective chemicals additives. Our theoretical thermodynamic studies suggested that in an isochoric system, living biological material could survive subfreezing temperatures, without any cryoprotective chemicals. By confirming the theoretical predictions, this paper suggests a new technology for subfreezing preservation of cells, organs and organisms of possible value for biotechnology and medicine as well as new possible mechanisms of living organism survival in nature.

A new minimally invasive tissue ablation technique, that combines the biophysical processes of electroporation and electrolysis, is introduced. The technology employs electrode needles inserted in the target tissue to deliver an Electrolytic Electroporation Waveform (EEW) in the form of an exponential decay voltage, several tens of microsecond long. A case study in a large animal model demonstrates that clinically significant size lesions can be achieved with a single, milliseconds long EEW. Ablation with EEW has major advantages over the comparable tissue ablation techniques of electrolysis, reversible electroporation and irreversible electroporation. EEW is orders of magnitude faster than conventional electrolytic ablation. EEW does not require the use of muscle relaxant as irreversible electroporation and EEW does not require injection of drugs as reversible electroporation. This new technology is simple to use and may become an important addition to the minimally invasive surgery armamentarium.

Electrolysis, electrochemotherapy with reversible electroporation, nanosecond pulsed electric fields and irreversible electroporation are valuable non-thermal electricity based tissue ablation technologies. This paper reports results from the first large animal study of a new non-thermal tissue ablation technology that employs "Synergistic electrolysis and electroporation" (SEE). The goal of this pre-clinical study is to expand on earlier studies with small animals and use the pig liver to establish SEE treatment parameters of clinical utility. We examined two SEE methods. One of the methods employs multiple electrochemotherapy-type reversible electroporation magnitude pulses, designed in such a way that the charge delivered during the electroporation pulses generates the electrolytic products. The second SEE method combines the delivery of a small number of electrochemotherapy magnitude electroporation pulses with a low voltage electrolysis generating DC current in three different ways. We show that both methods can produce lesion with dimensions of clinical utility, without the need to inject drugs as in electrochemotherapy, faster than with conventional electrolysis and with lower electric fields than irreversible electroporation and nanosecond pulsed ablation.