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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

Biosilicification drives a decline of dissolved si in the oceans through geologic time

Biosilicification has driven variation in the global Si cycle over geologic time. The evolution of different eukaryotic lineages that convert dissolved Si (DSi) into mineralized structures (higher plants, siliceous sponges, radiolarians, and diatoms) has driven a secular decrease in DSi in the global ocean leading to the low DSi concentrations seen today. Recent studies, however, have questioned t

Inconvenient human rights : Water and sanitation in Sweden’s informal Roma settlements

Following an increase in Roma migration under the European “freedom of movement” laws, Swedish municipalities initiated more than 80 evictions of informal Roma settlements on the grounds of poor sanitation between 2013 and 2016. These evictions echo policies from earlier in the 20th century, when Roma living in Sweden were often marginalized through the denial of access to water and sanitation fac

Large differences between carbon and nutrient loss rates along the land to ocean aquatic continuum—implications for energy : nutrient ratios at downstream sites

The balance between the availability of energy and nutrients is decisive for the growth and survival of organisms. Here, we evaluated how energy, in this study expressed as total carbon (TC), is lost along the land to ocean aquatic continuum (LOAC) in relation to nutrients, i.e., total phosphorus (TP), total nitrogen (TN), total iron (TFe), and dissolved silica (DSi). For the evaluation, we used d

Efficiency of the coastal filter : Nitrogen and phosphorus removal in the Baltic Sea

An important function of coastal ecosystems is the reduction of the nutrient flux from land to the open sea, the coastal filter. In this study, we focused on the two most important coastal biogeochemical processes that remove nitrogen and phosphorus permanently: denitrification and phosphorus burial. We compiled removal rates from coastal systems around the Baltic Sea and analyzed their spatial va

Jatte : A tunable tree editor for integrated DSLs

Complex systems often integrate domain-specific languages to let users customize the behavior. Developing tooling for such languages is typically time-consuming and error-prone. We present Jatte, a tool intended to simplify this development. Jatte works as a generic tree editor for an abstract syntax, but uses aspects and attribute grammars to support powerful modular ways of tuning both the proje

Combining hyperspectral UAV and multispectral Formosat-2 imagery for precision agriculture applications

Remote sensing is a key tool for precision agriculture applications as it is capable of capturing spatial and temporal variations in crop status. However, satellites often have an inadequate spatial resolution for precision agriculture applications. High-resolution Unmanned Aerial Vehicles (UAV) imagery can be obtained at flexible dates, but operational costs may limit the collection frequency. Th

"In Sweden we shake hands" - but are we really?

Motivated by a recent controversy over handshaking, a survey of the personal networks of young Swedes (n=2244) is used to describe greeting practices across social class, gender, immigrant background, and geographic location. While greeting practices in the sample are fairly uniform, there are also important differences. Handshaking is predominantly used by respondents with an immigrant background

Ten essentials for action-oriented and second order energy transitions, transformations and climate change research

The most critical question for climate research is no longer about the problem, but about how to facilitate the transformative changes necessary to avoid catastrophic climate-induced change. Addressing this question, however, will require massive upscaling of research that can rapidly enhance learning about transformations. Ten essentials for guiding action-oriented transformation and energy resea

A method for inductive measurement of equivalent electrical conductivity in thin non-consolidated multilayer carbon fibre fabrics

Carbon fibre fabrics are electrically conductive and therefore possess the prerequisites for being inductively heated. In-situ heating by induction could significantly reduce processing time and energy consumption during consolidation of carbon fibre composites, but to control the induction heating process properly the electrical conductivity of the fabric must be known. The work presented in this