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Primulic acid 1 is the main saponin present in Primula elatior. The present study describes the isolation of this amphiphilic compound from primula root. It was performed by ultrasonic maceration, reverse-phase column chromatography and crystallization. Investigations of its physicochemical property are represented by the determination of critical micelle concentration (cmc). The cmc value of the amphiphile was 9.4 × 10−5 mol·dm−3. The evaluation of environmental toxicity was performed on a daphnid species Simpocephalus expinosus s.l., which was very sensitive to primulic acids 1. The results from acute immobilisation test show that the tested compound has half maximal effective concentration after 24 hours (EC50-24 h) equal to 6.9 mg·l−1. Saponin can be classified as a toxic compound for aquatic organisms.

This document presents the findings of a study on the presence of eosinophils and basophils in patients with bullous pemphigoid (BP) and non-bullous pemphigoid (NBP) skin. The study found that the number of eosinophils and basophils was significantly higher in BP lesional skin compared to BP perilesional skin and NBP skin. The activation of eosinophils and basophils in BP lesional skin was also observed. These findings suggest that eosinophils and basophils play an important role in the pathophysiology of BP and may contribute to the itch experienced by pemphigoid patients. Further research is needed to validate these findings. [Extracted from the article]

Phase Resolved Optical Emission Spectroscopy (PROES) measurements combined with 1d3v Particle-in-Cell/Monte Carlo Collisions simulations are performed to investigate the excitation dynamics in low-pressure capacitively coupled plasmas (CCPs) in argon-oxygen mixtures. The system used for this study is a geometrically symmetric CCP reactor operated in a 70% Ar-30% O2 mixture at 120 Pa, applying a peak-to-peak voltage of 350 V, with a wide range of driving RF frequencies (2 MHz ⩽ f ⩽ 15 MHz). The measured and calculated spatio-temporal distributions of the electron impact excitation rates from the Ar ground state to the Ar 2 p 1 level show good qualitative agreement. The distributions show significant frequency dependence, which is generally considered to be predictive of transitions in the dominant discharge operating mode. Three frequency ranges can be distinguished, showing distinctly different excitation characteristics: (i) in the low frequency range ( f ⩽ 3 MHz), excitation is strong at the sheaths and weak in the bulk region; (ii) at intermediate frequencies (3.5 MHz ⩽ f ⩽ 5 MHz), the excitation rate in the bulk region is enhanced and shows striation formation; (iii) above 6 MHz, excitation in the bulk gradually decreases with increasing frequency. Boltzmann term analysis was performed to quantify the frequency-dependent contributions of the Ohmic and ambipolar terms to the electron power absorption. [ABSTRACT FROM AUTHOR]

Plasma simulations are powerful tools for understanding fundamental plasma science phenomena and for process optimisation in applications. To ensure their quantitative accuracy, they must be validated against experiments. In this work, such an experimental validation is performed for a one dimensional in space and three dimensional in velocity space particle-in-cell simulation complemented with the Monte Carlo treatment of collision processes of a capacitively coupled radio frequency plasma driven at 13.56 MHz and operated in neon gas. In a geometrically symmetric reactor the electron density in the discharge centre and the spatio-temporal distribution of the electron impact excitation rate from the ground into the Ne 2p1 level are measured by a microwave cutoff probe and phase resolved optical emission spectroscopy, respectively. The measurements are conducted for electrode gaps between 50 mm and 90 mm, neutral gas pressures between 20 mTorr and 50 mTorr, and peak-to-peak values of the driving voltage waveform between 250 V and 650 V. Simulations are performed under identical discharge conditions. In the simulations, various combinations of surface coefficients characterising the interactions of electrons and heavy particles with the anodised aluminium electrode surfaces are adopted. We find, that the simulations using a constant effective heavy particle induced secondary electron (SE) emission coefficient of 0.3 and a realistic electron–surface interaction model (which considers energy-dependent and material specific elastic and inelastic electron reflection, as well as the emission of true SEs from the surface) yield results which are in good quantitative agreement with the experimental data. [ABSTRACT FROM AUTHOR]

For the Hungarian People's Republic, the events of the world politics in the 1960s allowed for significant international activity. Respecting the framework of the regime, decades of active engagement on both sides of the Iron Curtain could be initiated. Considering the country's resources, one of the most important elements in its foreign relations efforts was the continuous expansion of cultural and educational relations, which allowed the country's higher education system--which experienced extensive growth during the same period--to play a prominent role. The Eötvös Loránd University (ELTE), one of the largest higher education institutions in Hungary, hosted students from nearly 90 countries with its diverse training portfolio. The internationalization process promoted by the government provided the university with a major opportunity to build a position in the wider international academic community, to establish partnerships, to diversify its training, and to improve its quality continuously. Relations with capitalist and developing countries were particularly valuable. At the same time, it was confronted with a number of problems in teaching and supporting incoming students, as well as systemic rigidities and inadequate funding, problems which remained unresolved before the transition. This paper seeks to showcase these processes through archival documents and contemporary press sources, examining the opportunities, constraints, and challenges from an institutional perspective, thus illustrating the frequent political ambitions of the state and its political institutions. [ABSTRACT FROM AUTHOR]

Particle-in-Cell/Monte Carlo Collision simulations are performed to investigate the effects of heavy-particle induced secondary electrons (SEs) on the ionization dynamics and on the control of ion properties at the electrodes in geometrically symmetric capacitively coupled argon discharges driven by tailored voltage waveforms. The driving voltage waveform is composed of a maximum of four (1 ≤ N ≤ 4) consecutive harmonics of the fundamental frequency of 13.56 MHz and is tailored by adjusting the identical phases of the even harmonics, θ. The simulations are carried out at neutral gas pressures of 3 Pa (nearly collisionless low-pressure regime) and 100 Pa (collisional high-pressure regime). Different approaches are used in the simulations to describe the secondary electron emission (SEE) at the electrodes: we adopt (i) constant ion-induced secondary electron emission coefficients (SEECs), γ , and (ii) realistic, energy-dependent SE yields for ions and fast neutrals. The mean ion energy at the electrodes, ⟨ E i ⟩ , can be controlled by θ at both pressures, for both approaches adopted to describe the SEE in the simulations. At a low pressure of 3 Pa, we obtain largely different dependencies of the ion flux at the electrodes, Γ i , on θ , depending on the value of the γ -coefficient. For γ = 0.2 , Γ i remains nearly constant as a function of θ , independently of the choice of N , i.e., the mean ion energy can be controlled separately from the ion flux by adjusting θ. However, for values of γ different from 0.2, the quality of the separate control of the ion properties changes significantly. At a high pressure of 100 Pa, independently of the choice of γ , for a given N ≥ 2 , the ion flux varies as a function of θ. At both pressures, the surface conditions affect the plasma parameters and the quality of the separate control of ion properties at the electrodes. Adopting realistic, energy-dependent SE yields for heavy particles in the simulations can lead to significantly different results compared to those obtained by assuming constant SEECs. [ABSTRACT FROM AUTHOR]