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Contact Allergy to Fragrance Mix II and Hydroxyisohexyl 3-Cyclohexene Carboxaldehyde : A Retrospective Study by International Contact Dermatitis Research Group

BACKGROUND: Fragrance mix II (FM II) is included in the baseline patch test series recommended by the International Contact Dermatitis Research Group (ICDRG). Hydroxyisohexyl 3-cyclohexene carboxaldehyde (HICC) is the most important sensitizer of the 6 fragrance materials included in FM II. Besides being a part of FM II, HICC is also tested separately in the ICDRG baseline series. OBJECTIVES: The

The Gaia-ESO Survey : An extremely Li-rich giant in globular cluster NGC 1261

Lithium-rich stars in globular clusters are rare. Only 14 have been found so far, in different evolutionary phases from dwarfs to giants. Different mechanisms have been proposed to explain this enhancement, but it is still an open problem. Using spectra collected within the Gaia-ESO Survey, obtained with the GIRAFFE spectrograph at the ESO Very Large Telescope, we present the discovery of the firs

PRDM15 is a key regulator of metabolism critical to sustain B-cell lymphomagenesis

PRDM (PRDI-BF1 and RIZ homology domain containing) family members are sequence-specific transcriptional regulators involved in cell identity and fate determination, often dysregulated in cancer. The PRDM15 gene is of particular interest, given its low expression in adult tissues and its overexpression in B-cell lymphomas. Despite its well characterized role in stem cell biology and during early de

Search for the HH → bb¯ bb¯ process via vector-boson fusion production using proton-proton collisions at √s = 13 TeV with the ATLAS detector

A search for Higgs boson pair production via vector-boson fusion (VBF) in the bb¯ bb¯ final state is carried out with the ATLAS experiment using 126 fb−1 of proton- proton collision data delivered at s = 13 TeV by the Large Hadron Collider. This search is sensitive to VBF production of additional heavy bosons that may decay into Higgs boson pairs, and in a non-resonant topology it can constrain th

Phase reconstruction of high-order harmonics by quantum path interference

We present a method to retrieve the phase of XUV light generated through high-order harmonic generation, by observing the intensity dependence of the interference pattern in the far-field. This interference pattern arises from electron trajectories in the generation process. These trajectories spend different time in the continuum and the phase of the generated light will therefore depend differen

Can we break the symmetry along the polarization axis in photoionization?

Photoionization is a fundamental process in which an electron is emitted from an atom. The emission is traditionally considered to be symmetric with respect to the polarization axis, unless it is temporally confined to a period shorter than an optical cycle time. We demonstrate that this symmetry can still be broken by combining a train of a few attosecond pulses and a dressing laser field. The li

Many-body calculations of two-photon, two color matrix elements for attosecond delays

Interferometric measurements based on the combination of extreme ultraviolet (XUV) attosecond pulse trains with weak infrared laser fields, have been successfully used to study time-resolved and recently angle-resolved photoemission in various atomic systems. These measurements rely on quantum interference between electron wavepackets created by absorption of XUV radiation, with further absorption

Fano's propensity rule in angle-resolved attosecond interferometry

Above-threshold ionization is a corner stone of attsecond science. In this work we extend Fano's propensity rule to two-photon above-threshold ionization and show that the asymmetry between absorption and emission of the second photon predicted by this propensity rule has strong implications for angle-resolved pump-probe experiments and in particular for attosecond photoelectron interferometry.

Opto-optical modulator (OOM) for extreme ultraviolet pulses

There is a profound, almost symbiotic relation between electrons and photons. When light interacts with matter the electrons in the material will start to move and oscillate. When a charged particle, such as an electron, oscillates it will act as a dipole and emit light. We utilize this symbiotic relation and extend the control of light to the extreme ultraviolet (XUV) region using the newly devel

Time-resolved dynamics of thiophene dication - Probing parent molecule survival times and multi-step dissociation processes of cyclic molecules by free-electron-laser experiments combined with theoretical simulations

Thiophene is a cyclic molecule that becomes unstable as a molecular dication. We followed the multi-step dissociation dynamics triggered by soft x-ray FEL pulses from SACLA, core-ionizing the S 2p orbital and creating parent dications by the Auger decay. The time-evolution was probed by optical laser pulsesthat reveal the survival lifetime of the parent dication and the build-up of fragmentation p

X-ray spectroscopy on ultrafast-decaying core-excited atomic ions

Results from the first soft X-ray user experiment at the European XFEL on nonlinear photon-matter interaction will be presented. Angle-resolved electron time-of-flight spectroscopy employed at the AQS (Atomic- like Quantum Systems) endstation of the SQS (Small Quantum Systems) instrument reveals insight into the character of resonances in highly transient, core ionized neon ions, i.e. Ne:+ 1s12s22

Ultrafast ionization and fragmentation dynamics of polycyclic atomatic hydro-carbons by XUV radiation

In the interstellar medium polycyclic aromatic hydrocarbon molecules (PAH) are exposed to strong ionizing radation leading to complex organic photochemistry. We investigated these ultrafast fragmentation reac-tions after ionization of the PAHs phenanthrene, fluorene and pyrene at a wavelength of 30.3 nm using pump probe spectroscopy at a free electron laser. We observe double ionization and afterw

Optimized vs. Standard Automated Peritoneal Dialysis Regimens (OptiStAR) : Study protocol for a randomized controlled crossover trial

Background: It has been estimated that automated peritoneal dialysis (APD) is currently the fastest growing renal replacement therapy in the world. However, in light of the growing number of diabetic patients on peritoneal dialysis (PD), the unwanted glucose absorption during APD remains problematic. Recent results, using an extended 3-pore model of APD, indicated that large reductions in glucose

Influence of user-related parameters on calculated energy use in low-energy school buildings

Literature and experience show that there are large discrepancies between the calculated and measured building energy usages, where user-related parameters are significant factors with regard to energy use in low-energy buildings. Furthermore, the difficulties encountered when quantifying these parameters compound these discrepancies. The main aim of this study was to provide feedback that would h

Foreign demand for agricultural commodities drives virtual carbon exports from Cambodia

Rapid deforestation is a major sustainability challenge, partly as the loss of carbon sinks exacerbates global climate change. In Cambodia, more than 13% of the total land area has been contracted out to foreign and domestic agribusinesses in the form of economic land concessions, causing rapid large-scale land use change and deforestation. Additionally, the distant drivers of local and global env

Under-reported relationship: a comparative study of pharmaceutical industry and patient organisation payment disclosures in the UK (2012-2016)

Objectives To examine the under-reporting of pharmaceutical company payments to patient organisations by donors and recipients. Design Comparative descriptive analysis of payments disclosed on drug company and charity regulator websites. Setting UK. Participants 87 donors (drug companies) and 425 recipients (patient organisations) reporting payments in 2012-2016. Main outcome measures. Number and

Obstetric and intensive-care strategies in a high-risk pregnancy with critical respiratory failure due to COVID-19 : A case report

Background: With the disease burden increasing daily, there is a lack of evidence regarding the impact of COVID-19 in pregnancy. Healthy pregnant women are still not regarded as a susceptible group despite physiological changes that make pregnant women more vulnerable to severe infection. However, high-risk pregnancies may be associated with severe COVID-19 disease with respiratory failure, as out

Pebble-driven planet formation around very low-mass stars and brown dwarfs

We conduct a pebble-driven planet population synthesis study to investigate the formation of planets around very low-mass stars and brown dwarfs in the (sub)stellar mass range between 0.01 M- and 0.1 M-. Based on the extrapolation of numerical simulations of planetesimal formation by the streaming instability, we obtain the characteristic mass of the planetesimals and the initial mass of the proto