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X-ray-Induced Photoreduction of Hg(II) in Aqueous Frozen Solution Yields Nearly Monatomic Hg(0)

We use X-ray-induced photochemistry, which is well known to cause changes in a number of systems, to reduce Hg(II) to Hg(0) in frozen aqueous solution with added glycerol maintained at 10 K. X-ray absorption spectroscopy was used to monitor the extent of the reaction and to characterize the species. An analysis of the extended X-ray absorption fine structure (EXAFS) of the photochemical product in

Excited‐State Topology Modifications of the Dihydroazulene Photoswitch Through Aromaticity

The gain and loss of aromaticity plays a key role in organic chemistry and in the prediction of rate‐determining steps. Herein, we explore the concept of aromaticity in photoisomerization reactions. Benzannulated derivatives of the dihydroazulene‐vinylheptafulvene (DHA‐VHF) photoswitch were investigated using transient absorption spectroscopy and time‐dependent density functional theory to elucida

Consensus recommendations on the classification, definition and diagnostic criteria of hip-related pain in young and middle-aged active adults from the International Hip-related Pain Research Network, Zurich 2018

There is no agreement on how to classify, define or diagnose hip-related pain-a common cause of hip and groin pain in young and middle-aged active adults. This complicates the work of clinicians and researchers. The International Hip-related Pain Research Network consensus group met in November 2018 in Zurich aiming to make recommendations on how to classify, define and diagnose hip disease in you

Universities in international networks

This chapter examines the international networks of some universities in Europe. Contacts between universities and researchers are often made easier by formal organisational links, associations and agreements. The ways of organizing research and higher education vary from country to country. Sweden differs from many of the others in that a greater proportion of the research in progress is conducte

Territories and networks in Europe : In search of a spatial order

Medieval Europe was characterized by geopolitical disorder and territorial disunion. Around 1500 AD, as the modern era dawned, Europe comprised some 1,500 districts which were largely politically independent. Gradually, medium sized territories emerged around cores made up of cultural, economic, and political centres. The Lake Malar area in Sweden was such a territory; London, Paris, Berlin-Potsda

Study of Multi-neutron Systems with SAMURAI Spectrometer

The tetraneutron has been drawing the attention of the nuclear physics community for decades, but a firm conclusion on its existence and properties is still far from being reached despite many experimental and theoretical efforts. New measurements have recently been performed at RIBF with the SAMURAI spectrometer by applying complementary reaction probes, which will help to pin down the properties

Kaonic Deuterium Precision Measurement at DA Φ NE : The SIDDHARTA-2 Experiment

Light kaonic atoms spectroscopy offers the unique opportunity to perform experiments equivalent to scattering at vanishing relative energies. This allows the determination of the antikaon-nucleus interaction at threshold, without the need of extrapolation to zero energy, as in the case of scattering experiments. In this framework, the SIDDHARTA-2 collaboration aims to perform the first measurement

Review of computer based approaches for modeling and simulating critical infrastructures as Socio-Technical Systems

The paper presents a review of the scientific literature on computer modeling of sociotechnical systems. The aim is to briefly review and discuss modeling approaches that are suitable for the simulation of socio-technical systems, specifically in the context of risk and vulnerability analysis of critical infrastructures. It is found that seven main socio-technical modeling approaches can be discer

Vibrational wavepacket dynamics in Fe carbene photosensitizer determined with femtosecond X-ray emission and scattering

The non-equilibrium dynamics of electrons and nuclei govern the function of photoactive materials. Disentangling these dynamics remains a critical goal for understanding photoactive materials. Here we investigate the photoinduced dynamics of the [Fe(bmip)2]2+ photosensitizer, where bmip = 2,6-bis(3-methyl-imidazole-1-ylidine)-pyridine, with simultaneous femtosecond-resolution Fe Kα and Kβ X-ray em

Vibronic coherence contributes to photocurrent generation in organic semiconductor heterojunction diodes

Charge separation dynamics after the absorption of a photon is a fundamental process relevant both for photosynthetic reaction centers and artificial solar conversion devices. It has been proposed that quantum coherence plays a role in the formation of charge carriers in organic photovoltaics, but experimental proofs have been lacking. Here we report experimental evidence of coherence in the charg

Cerebrospinal fluid lipocalin 2 as a novel biomarker for the differential diagnosis of vascular dementia

The clinical diagnosis of vascular dementia (VaD) is based on imaging criteria, and specific biochemical markers are not available. Here, we investigated the potential of cerebrospinal fluid (CSF) lipocalin 2 (LCN2), a secreted glycoprotein that has been suggested as mediating neuronal damage in vascular brain injuries. The study included four independent cohorts with a total n = 472 samples. LCN2

Ultracompact 3D microfluidics for time-resolved structural biology

To advance microfluidic integration, we present the use of two-photon additive manufacturing to fold 2D channel layouts into compact free-form 3D fluidic circuits with nanometer precision. We demonstrate this technique by tailoring microfluidic nozzles and mixers for time-resolved structural biology at X-ray free-electron lasers (XFELs). We achieve submicron jets with speeds exceeding 160 m s−1, w

Lubrication characteristics of wax esters from oils produced by a genetically-enhanced oilseed crop

In this study, purified by a newly developed method Crambe (Crambe abyssinica) oil wax esters were mixed with conventional Crambe oil to examine the lubrication characteristics of bio-based wax esters and their blends. The Quartz Crystal Microbalance (QCM) results indicate high thermal stability of wax esters and their mixtures which is further supported by observed small viscosity change with tem

Dynamic in-situ imaging of methane hydrate formation and self-preservation in porous media

We present the results of dynamic in-situ 3D X-ray imaging of methane hydrates microstructure during methane hydrate formation and dissociation in sand samples. Short scanning times and high resolution provided by synchrotron X-rays allowed for better understanding of water movement and different types of gas-hydrate formation. Complementing previous observations, we conclude that the process of g