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Electronic structure of an [FeFe] hydrogenase model complex in solution revealed by X-ray absorption spectroscopy using narrow-band emission detection

High-resolution X-ray absorption spectroscopy with narrow-band X-ray emission detection, supported by density functional theory calculations (XAES-DFT), was used to study a model complex, ([Fe2(μ-adt)(CO) 4(PMe3)2] (1, adt = S-CH2-(NCH 2Ph)-CH2-S), of the [FeFe] hydrogenase active site. For 1 in powder material (1powder), in MeCN solution (1′), and in its three protonated states (1H, 1Hy, 1HHy; H

The S1 split signal of photosystem II; a tyrosine-manganese coupled interaction

Detailed optical and EPR analyses of states induced in dark-adapted PS II membranes by cryogenic illumination permit characterization and quantification of all pigment derived donors and acceptors, as well as optically silent (in the visible, near infrared) species which are EPR active. Near complete turnover formation of QA- is seen in all centers, but with variable efficiency, depending on the d

The Streets are Talking to Me : Affective Fragments in Sisi’s Egypt

This sophisticated book presents new theoretical and analytical insights into the momentous events in the Arab world that began in 2011 and, more importantly, into life and politics in the aftermath of these events. Focusing on the qualities of the sensory world, Maria Frederika Malmström explores the dramatic differences after the Egyptian revolution and their implications for society—the lack of

Pragmatism i dansk sakrätt – särskilt om panträttsliga aspekter

Trots att nordisk rätt i stor utsträckning präglas av en funktionalistiskt inställning så skiljer sig uppfattningen om hur frågeställningar inom den dynamiska sakrätten ska lösas länderna emellan. I artikeln åskådliggörs hur det svenska förhållningssättet präglas av lagstadgade regler, medan det i Danmark finns en mjukare och tämligen pragmatiskt attityd med utrymme för mer nyanserade lösningar. F

Studying the “Pelagius and Johannes” collection of Sayings of the Desert Fathers : Steps towards a new edition of the Latin reception

The sayings of the Desert Fathers had an important role in the monastic education and were very widespread. Originally written down in Greek, they were soon translated into all the main languages in the medieval Europe, and underwent transformations as they were copied. The sayings were organized in different ways, mainly alphabetically or according to themes, and as they were copied the repertoir

A crystallographic and Mo K-edge XAS study of molybdenum oxo bis-, mono-, and non-dithiolene complexes-first-sphere coordination geometry and noninnocence of ligands

Ten square-based pyramidal molybdenum complexes with different sulfur donor ligands, that is, a variety of dithiolenes and sulfides, were prepared, which mimic coordination motifs of the molybdenum cofactors of molybdenum-dependent oxidoreductases. The model compounds were investigated by Mo K-edge X-ray absorption spectroscopy (XAS) and (with one exception) their molecular structures were analyze

Effects of pH on the S3 state of the oxygen evolving complex in photosystem II probed by EPR split signal induction

The electrons extracted from the CaMn4 cluster during water oxidation in photosystem II are transferred to P680+ via the redox-active tyrosine D1-Tyr161 (YZ). Upon YZ oxidation a proton moves in a hydrogen bond toward D1-His190 (HisZ). The deprotonation and reprotonation mechanism of YZ-OH/Y Z-O is of key importance for the catalytic turnover of photosystem II. By light illumination at liquid heli

Metalloradical EPR signals from the YZ·S-State intermediates in photosystem II

The redox-active tyrosine residue (YZ) plays a crucial role in the mechanism of the water oxidation. Metalloradical electron paramagnetic resonance (EPR) signals reflecting the light-induced YZ· in magnetic interaction with the CaMn4-cluster in the particular S-state, YZ·SX intermediates, have been found in intact photosystem II. These so-called split EPR signals are induced by illumination at cry

Formation spectra of the EPR split signals from the S0, S 1, and S3 states in photosystem II induced by monochromatic light at 5 K

The interaction EPR split signals from photosystem II (PSII) have been reported from the S0, S1, and S3 states. The signals are induced by illumination at cryogenic temperatures and are proposed to reflect the magnetic interaction between YZ• and the Mn 4Ca cluster. We have investigated the formation spectra of these split EPR signals induced in PSII enriched membranes at 5 K using monochromatic l

The role of place in city centre retailing

City centre offerings, including shopping, restaurants and cafés, and a lively atmosphere are vital place attributes, which together with several other elements create an attractive place. However, city centre retailing is facing serious competition from e-commerce and external shopping malls, and dying city centres appear to have become a worldwide epidemic in the last decade. To retain visitors

Opportunities and Challenges of a Small State Presidency: The Estonian Council Presidency 2017

This article discusses some of the opportunities and challenges that the Estonian Council Presidency is facing during its first term in 2017. We also explore how Estonia is likely to appreach this position. The Council presidency provides a position to propagate national interests and an opportunity for leadership within the Council but can also be preceived as a silencer of domestic narrative. We

Role of cyclin-dependent kinase 2 in the progression of mouse juvenile cystic kidney disease

A hallmark of polycystic kidney diseases (PKDs) is aberrant proliferation, which leads to the formation and growth of renal cysts. Proliferation is mediated by cyclin-dependent kinases (Cdks), and the administration of roscovitine (a pan-Cdk inhibitor) attenuates renal cystic disease in juvenile cystic kidney (jck) mice. Cdk2 is a key regulator of cell proliferation, but its specific role in PKD r

Regulation of fungal decomposition at single-cell level

Filamentous fungi play a key role as decomposers in Earth’s nutrient cycles. In soils, substrates are heterogeneously distributed in microenvironments. Hence, individual hyphae of a mycelium may experience very different environmental conditions simultaneously. In the current work, we investigated how fungi cope with local environmental variations at single-cell level. We developed a method based

Momentum-resolved resonant inelastic soft X-ray scattering (qRIXS) endstation at the ALS

A momentum resolved resonant inelastic X-ray scattering (qRIXS) experimental station with continuously rotatable spectrometers and parallel detection is designed to operate at different beamlines at synchrotron and free electron laser (FEL) facilities. This endstation, currently located at the Advanced Light Source (ALS), has five emission ports on the experimental chamber for mounting the high-th

Simple carbohydrate derivatives diminish the formation of biofilm of the pathogenic yeast candida albicans

The opportunistic human fungal pathogen Candida albicans relies on cell morphological transitions to develop biofilm and invade the host. In the current study, we developed new regulatory molecules, which inhibit the morphological transition of C. albicans from yeast-form cells to cells forming hyphae. These compounds, benzyl α-l-fucopyranoside and benzyl β-d-xylopyranoside, inhibit the hyphae for