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Direct Evidence for Reaction between Cellulose and CO2from Nuclear Magnetic Resonance

The direct reaction between carbohydrates and CO2 has recently attracted attention in the context of cellulose dissolution and derivatization as well as carbon capture applications. We have directly demonstrated the formation of cellulose carbonate upon the introduction of CO2 into a non-aqueous cellulose solution by nuclear magnetic resonance spectroscopy. Comparison of the observed spectra with

Charge Regulation during Amyloid Formation of α-Synuclein

Electrostatic interactions play crucial roles in protein function. Measuring pKa value perturbations upon complex formation or self-assembly of e.g. amyloid fibrils gives valuable information about the effect of electrostatic interactions in those processes. Site-specific pKa value determination by solution NMR spectroscopy is challenged by the high molecular weight of amyloid fibrils. Here we rep

Nonclassical Hydrophobic Effect in Micellization : Molecular Arrangement of Non-Amphiphilic Structures

Micellization brought about by nonclassical hydrophobic effect invokes enthalpy as the driving force. Thus, the underlying molecular phenomena differ from the entropically dominated hydrophobic effect. In quest for a molecular-scale understanding, we report on the molecular arrangement of nonamphiphilic structures of an anionic boron cluster compound, COSAN. We synergistically combine experimental

Ion binding to biomolecules

We investigated specific anion binding to basic amino acid residues as well as to a range of patchy protein models. This microscopic information was subsequently used to probe protein–protein interactions for aqueous lysozyme solutions. Using computer simulations to study both atomistic and coarse grained protein molecules, it is shown that the ion–protein interaction mechanism as well as magnitud

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Hvorfor skal den vigtige debat om Spotifys indflydelse på musiklytning og musikoplevelse ende som et ufrugtbart møde mellem et personangreb og en forsvarstale? Er Seismografs læsere mon blevet klogere på, hvad Spotifys digitale infrastruktur kan gøre ved brugerens lytteoplevelse? Streaming-forskeren Andreas Helles Pedersen hiver et tredje øre ind i debatten.

Patchy proteins, anions and the Hofmeister series

We investigate specific anion binding to a range of patchy protein models and use our results to probe protein-protein interactions for aqueous lysozyme solutions. Our molecular simulation studies show that the ion-protein interaction mechanism and strength largely depend on the nature of the interfacial amino acid residues. Via direct ion pairing, small anions interact with charged side-chains wh

Specific ion binding to macromolecules : Effects of hydrophobicity and ion pairing

Using molecular dynamics simulations in an explicit aqueous solvent, we examine the binding of fluoride versus iodide to a spherical macromolecule with both hydrophobic and positively charged patches. Rationalizing our observations, we divide the ion association interaction into two mechanisms: (1) poorly solvated iodide ions are attracted to hydrophobic surface patches, while (2) the strongly sol

Ion pairing as a possible clue for discriminating between sodium and potassium in biological and other complex environments

For a series of biologically relevant anions, we present free energy changes upon replacing potassium with sodium in a contact ion pair. Calculations performed using a combination of molecular dynamics simulations and ab initio methods demonstrate the ordering of anions in a Hofmeister series. Small anionic groups such as carboxylates preferentially pair with sodium, while intermediate cases such

Coarse graining biomolecular systems

Proteins in the living cell can interact with a wide variety of solutes, ranging from ions, peptides, other proteins, DNA to membranes. Charged groups play a major role and solution conditions such as pH and ionic strength can modulate the interactions significantly. Describing these systems in a statistical mechanical framework involves thousands of pair-interactions and therefore a certain amoun

Focusing properties of attosecond pulses

The discovery of high-order harmonic generation (HHG) has made it possible to see the electron dynamics on their natural time scale, attoseconds. In the HHG process, a femtosecond infrared (IR) laser pulse is converted into a train of attosecond pulses in the extreme ultraviolet (XUV), but with a very low conversion efficiency. The low intensity has to be used efficiently and that means keeping th

Focusing Properties of High-Order Harmonics

Many applications of the extreme ultraviolet (XUV) radiation obtained by high-order harmonic generation (HHG) in gases require a small focus area in order to enable attosecond pulses to reach a high intensity. Here, high-order harmonics generated in Ar with a multiterawatt laser system in a loose focusing geometry are focused to a few micrometers using two toroidal mirrors in a Wolter configuratio

‘Fake News, Hypocrites!’ : The Rhetoric of Blame from Jesus to Trump

Blame (vituperation) is a rhetorical practice well-known in classical Rhetoric, and to orators of the first century C.E. Following an overview of vituperation in classical handbooks, the study presents on overview of vituperation in select New Testament texts, including a gospel and letters of Paul. Similarities with President Donald Trump's rhetoric are noted and both ancient and contemporary use

Reliable and valid assessment of procedural skills in resuscitative endovascular balloon occlusion of the aorta

BACKGROUND Valid and reliable assessment of skills is essential for improved and evidence-based training concepts. In a recent study, we presented a novel tool to assess procedural skills in resuscitative endovascular balloon occlusion of the aorta (REBOA), REBOA-RATE, based on international expert consensus. Although expert consensus is a strong foundation, the performance of REBOA-RATE has not b

Tuberculosis treatment outcome and predictors in africa : A systematic review and meta-analysis

This review aimed to summarize and estimate the TB treatment success rate and factors associated with unsuccessful TB treatment outcomes in Africa. Potentially eligible primary studies were retrieved from PubMed and Google Scholar. The risk of bias and quality of studies was assessed using The Joanna Briggs Institute’s (JBI) appraisal criteria, while heterogeneity across studies was assessed using

Composition and Seasonality of Membrane Transporters in Marine Picoplankton

In this study, we examined transporter genes in metagenomic and metatranscriptomic data from a time-series survey in the temperate marine environment of the Baltic Sea. We analyzed the abundance and taxonomic distribution of transporters in the 3μm–0.2μm size fraction comprising prokaryotes and some picoeukaryotes. The presence of specific transporter traits was shown to be guiding the succession

EH Domain-Containing 2 Deficiency Restricts Adipose Tissue Expansion and Impairs Lipolysis in Primary Inguinal Adipocytes

Lipid uptake can be facilitated via caveolae, specific plasma membrane invaginations abundantly expressed in adipocytes. The dynamin-related protein EH domain-containing 2 (EHD2) stabilizes caveolae at the cell surface. Here, we have examined the importance of EHD2 for lipid handling using primary adipocytes isolated from EHD2 knockout (Ehd2−/−) C57BL6/N mice. Following high-fat diet (HFD) feeding

Bone-Specific Metastasis Pattern of Advanced-Stage Lung Adenocarcinoma According to the Localization of the Primary Tumor

Background: Patients with advanced-stage lung adenocarcinoma (LADC) often develop distant metastases in the skeletal system. Yet, the bone-specific metastasis pattern is still controversial. We, therefore, aimed to examine how the primary tumor location affects bone specificity and survival in LADC patients diagnosed with skeletal metastases. Methods: In total, 209 bone-metastatic Caucasian LADC p