N‐heterocyclic carbene catalyzed photoenolization/Diels–Alder reaction of acid fluorides

The combination of light activation and N‐heterocyclic carbene (NHC) organocatalysis has enabled the use of acid fluorides as substrates in a UVA‐light‐mediated photochemical transformation previously observed only with aromatic aldehydes and ketones. Stoichiometric studies and TD‐DFT calculations support a mechanism involving the photoactivation of an ortho‐toluoyl azolium intermediate, which exhibits “ketone‐like” photochemical reactivity under UVA irradiation. Using this photo‐NHC catalysis approach, a novel photoenolization/Diels–Alder (PEDA) process was developed that leads to diverse isochroman‐1‐one derivatives

Mental health-related communication in a virtual community: text mining analysis of a digital exchange platform during the Covid-19 pandemic.

BACKGROUND Virtual communities played an important role in mental health and well-being during the Covid-19 pandemic by providing access to others and thereby preventing loneliness. The pandemic has accelerated the urge for digital solutions for people with pre-existing mental health problems. So far, it remains unclear how the people concerned communicate with each other and benefit from peer-to-peer support on a moderated digital platform. OBJECTIVE The aim of the project was to identify and describe the communication patterns and verbal expression of users on the inCLOUsiv platform during the first lockdown in 2020. METHODS Discussions in forums and live chats on inCLOUsiv were analysed using text mining, which included frequency, correlation, n-gram and sentiment analyses. RESULTS The communication behaviour of users on inCLOUsiv was benevolent and supportive; and 72% of the identified sentiments were positive. Users addressed the topics of 'corona', 'anxiety' and 'crisis' and shared coping strategies. CONCLUSIONS The benevolent interaction between users on inCLOUsiv is in line with other virtual communities for Covid-19 and the potential for peer-to-peer support. Users can benefit from each other's experiences and support each other. Virtual communities can be used as an adjuvant to existing therapy, particularly in times of reduced access to local health services

Оценка пригодности сиштофа для получения пеностекольных материалов

In this work gives the analysis of suitability of use of by-product processing aluminum for manufacture of heat-insulating material construction purpose

Arrival time and intensity binning at unprecedented repetition rates

Understanding dynamics on ultrafast timescales enables unique and new insights into important processes in the materials and life sciences. In this respect, the fundamental pump-probe approach based on ultra-short photon pulses aims at the creation of stroboscopic movies. Performing such experiments at one of the many recently established accelerator-based 4th-generation light sources such as free-electron lasers or superradiant THz sources allows an enormous widening of the accessible parameter space for the excitation and/or probing light pulses. Compared to table-top devices, critical issues of this type of experiment are fluctuations of the timing between the accelerator and external laser systems and intensity instabilities of the accelerator-based photon sources. Existing solutions have so far been only demonstrated at low repetition rates and/or achieved a limited dynamic range in comparison to table-top experiments, while the 4th generation of accelerator-based light sources is based on superconducting radio-frequency technology, which enables operation at MHz or even GHz repetition rates. In this article, we present the successful demonstration of ultra-fast accelerator-laser pump-probe experiments performed at an unprecedentedly high repetition rate in the few- hundred-kHz regime and with a currently achievable optimal time resolution of 13 fs (rms). Our scheme, based on the pulse-resolved detection of multiple beam parameters relevant for the experiment, allows us to achieve an excellent sensitivity in real-world ultra-fast experiments, as demonstrated for the example of THz-field-driven coherent spin precession

Ultrafast High-Field THz beamline at X-ray FEL

THz sources at FLASH utilize spent electron beam from a soft X-ray FEL to generate very intense (up to 150µJ), tunable frequency (1-300THz) and ultrafast narrowband (~10%) THz pulses, which are naturally synchronized to soft X-ray pulses [1]. This unique combination allows for wide range of element specific pump-probe experiments in physics, material science and biology. Here we discuss the unique features of the FLASH THz pulses and the accelerator source that bring along a set of challenges in the diagnostics of their key parameters: pulse energy, spectral, temporal and spatial profiles.VII International School and Conference on Photonics : PHOTONICA2019 : Abstracts of Tutorial, Keynote, Invited Lectures, Progress Reports and Contributed Papers; August 26-30; Belgrad

The role of mechanotransduction versus hypoxia during simulated orthodontic compressive strain—an in vitro study of human periodontal ligament fibroblasts

During orthodontic tooth movement (OTM) mechanical forces trigger pseudo-inflammatory, osteoclastogenic and remodelling processes in the periodontal ligament (PDL) that are mediated by PDL fibroblasts via the expression of various signalling molecules. Thus far, it is unknown whether these processes are mainly induced by mechanical cellular deformation (mechanotransduction) or by concomitant hypoxic conditions via the compression of periodontal blood vessels. Human primary PDL fibroblasts were randomly seeded in conventional six-well cell culture plates with O-2-impermeable polystyrene membranes and in special plates with gas-permeable membranes (Lumox (R), Sarstedt), enabling the experimental separation of mechanotransducive and hypoxic effects that occur concomitantly during OTM. To simulate physiological orthodontic compressive forces, PDL fibroblasts were stimulated mechanically at 2 g.cm(-2) for 48 h after 24 h of pre-incubation. We quantified the cell viability by MTT assay, gene expression by quantitative real-time polymerase chain reaction (RT-qPCR) and protein expression by western blot/enzyme-linked immunosorbent assays (ELISA). In addition, PDL-fibroblast-mediated osteoclastogenesis (TRAP(+) cells) was measured in a 72-h coculture with RAW264.7 cells. The expression of HIF-1 alpha, COX-2, PGE2, VEGF, COL1A2, collagen and ALPL, and the RANKL/OPG ratios at the mRNA/protein levels during PDL-fibroblast-mediated osteoclastogenesis were significantly elevated by mechanical loading irrespective of the oxygen supply, whereas hypoxic conditions had no significant additional effects. The cellular-molecular mediation of OTM by PDL fibroblasts via the expression of various signalling molecules is expected to be predominantly controlled by the application of force (mechanotransduction), whereas hypoxic effects seem to play only a minor role. In the context of OTM, the hypoxic marker HIF-1 alpha does not appear to be primarily stabilized by a reduced O-2 supply but is rather stabilised mechanically

High-field high-repetition-rate sources for the coherent THz control of matter

Ultrashort flashes of THz light with low photon energies of a few meV, but strong electric or magnetic field transients have recently been employed to prepare various fascinating nonequilibrium states in matter. Here we present a new class of sources based on superradiant enhancement of radiation from relativistic electron bunches in a compact electron accelerator that we believe will revolutionize experiments in this field. Our prototype source generates high-field THz pulses at unprecedented quasicontinuous-wave repetition rates up to the MHz regime. We demonstrate parameters that exceed state-of-the-art laser-based sources by more than 2 orders of magnitude. The peak fields and the repetition rates are highly scalable and once fully operational this type of sources will routinely provide 1 MV/cm electric fields and 0.3 T magnetic fields at repetition rates of few 100 kHz. We benchmark the unique properties by performing a resonant coherent THz control experiment with few 10 fs resolution

[pain]Byte VR Storytelling & Classical Ballet

This initial stage paper focuses on the Virtual Reality (VR) experience of the [pain]Byte ballet. The live and VR experience debut October 1st 2017, as part of the Brighton digital festival. Specifically, the development of the VR environment to compliment live performance by using the same choreography to create an option capture element of the VR story telling experience. Reviewing Virtual & Alternative reality gaming & storytelling works and the use of VR for chronic pain management (Chen, Win). Does the VR experience compare to that of the live theatre for the audience? The data visualisations and VR environment will be continuations of the Network Simulator, [data]Storm 2015. We are visualising and comparing the pain pathway system to that of a social network. Linking pain signals to viral/negative messaging for some of the visuals. The main purpose of the pieces links to how “we" present ourselves online, these better or veiled versions of ourselves. For chronic pain sufferers, this can be daily activity in the real world. The paper concludes by identifying some future directions for the research project. The Ballet: [pain]Byte is a data driven dance classical ballet performance and VR (virtual reality) experience. [pain]Byte, is about chronic pain and biomedical engineering, in particular the use of implanted technology - neuromodulation (Al-Kaisey et al). Using data as a medium for storytelling, what it means to be in chronic pain. The live augmented theatre and VR experience research focuses on how an audience’s exposure and understanding are impacted by the difference mediums used for [pain]byte