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Estimating average shock pressures recorded by impactite samples based on universal stage investigations of planar deformation features in quartz-Sources of error and recommendations

Planar deformation features (PDFs) in quartz are the most widely used indicator of shock metamorphism in terrestrial rocks. They can also be used for estimating average shock pressures that quartz-bearing rocks have been subjected to. Here we report on a number of observations and problems that we have encountered when performing universal stage measurements and crystallographically indexing of PD

Physiological acclimation dampens initial effects of elevated temperature and atmospheric CO2 concentration in mature boreal Norway spruce

Physiological processes of terrestrial plants regulate the land-atmosphere exchange of carbon, water, and energy, yet few studies have explored the acclimation responses of mature boreal conifer trees to climate change. Here we explored the acclimation responses of photosynthesis, respiration, and stomatal conductance to elevated temperature and/or CO2 concentration ([CO2]) in a 3-year field exper

Control of Enantioselectivity in Rhodium(I) Catalysis by Planar Chiral Dibenzo[a,e]cyclooctatetraenes

Planar chiral 5,11-disubstiuted dibenzo[a,e]cyclo-octatetraenes (dbCOTs) have been developed as the first useful chiral homologs to dbCOT-ligands for asymmetric applications. Methods enabling the preparation of such compounds on a gram-scale in enantiomerically pure form are described. Evaluated as ligands in rhodium(I)-catalyzed 1,4- and 1,2-arylation reactions, tertiary and quarternary stereogen

Spectral-luminescent properties of meso-tetraarylporphyrins revisited : The role of aryl type, substitution pattern and macrocycle core protonation

Both the ground (S0) and the lowest singlet excited states (S1) for a series of 5,10,15,20-tetraarylporphyrins consisting of two symmetrically and four asymmetrically substituted derivatives (A4, AB3, trans-A2B2, cis-A2B2, A3B and B4, where A=phenyl and B=mesityl) are studied by absorption and fluorescence spectroscopies. The rotational degree of freedom of the aryl rings is found to play a crucia

Meningioma growth dynamics assessed by radiocarbon retrospective birth dating

It is not known how long it takes from the initial neoplastic transformation of a cell to the detection of a tumor, which would be valuable for understanding tumor growth dynamics. Meningiomas show a broad histological, genetic and clinical spectrum, are usually benign and considered slowly growing. There is an intense debate regarding their age and growth pattern and when meningiomas should be re

Refugees in Europe : national overviews from key countries with a special focus on child and adolescent mental health

Many European countries are becoming multicultural at a previously unseen rate. The number of immigrants including refugees has considerably increased since 2008, and especially after the beginning of the war in Syria. In 2015, 88,300 unaccompanied minors sought asylum in the Member States of the European Union (EU) and most came from Syria, Afghanistan, Iran, Iraq, Somalia and Eritrea. As a react

Naphthyl Thio- and Carba-xylopyranosides for Exploration of the Active Site of β-1,4-Galactosyltransferase 7 (β4GalT7)

Xyloside analogues with substitution of the endocyclic oxygen atom by sulfur or carbon were investigated as substrates for β-1,4-galactosyltransferase 7 (β4GalT7), a key enzyme in the biosynthesis of glycosaminoglycan chains. The analogues with an endocyclic sulfur atom proved to be excellent substrates for β4GalT7, and were galactosylated approximately fifteen times more efficiently than the corr

Methanol Desorption from Cu-ZSM-5 Studied by in Situ Infrared Spectroscopy and First-Principles Calculations

The dynamic interaction of methanol and its derivatives with Cu-exchanged ZSM-5 during methanol temperature-programmed desorption from 30 to 450 °C has been investigated using in situ diffuse reflectance infrared Fourier transform spectroscopy and first-principles calculations. The results emphasize that defects in the framework structure of the zeolite and Brønsted acid sites constitute ion-excha

Parallel-Coupled Quantum Dots in InAs Nanowires

We use crystal-phase tuning during epitaxial growth of InAs nanowires to create quantum dots with very strong confinement. A set of gate electrodes are used to reproducibly split the quantum dots into even smaller pairs for which we can control the populations down to the last electron. The double quantum dots, which are parallel-coupled to source and drain, show clear and stable odd-even level pa