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Versificandi mania : University Teaching of Greek and Greek Verse and Prose in dissertations in Sweden

In his history of Swedish poets who wrote in (Humanist) Greek (1785–9), Matthias Floderus claimed that before his time such a mania for versification raged in the Swedish universities in Uppsala, Turku, Tartu, and Lund that hardly one academic specimen appeared without it being embellished with Greek verses by students – also prose texts occur. That claim is only slightly exaggerated. This paper p

Structural differences of oxidized iron-sulfur and nickel-iron cofactors in O2-tolerant and O2-sensitive hydrogenases studied by X-ray absorption spectroscopy

The class of [NiFe]-hydrogenases comprises oxygen-sensitive periplasmic (PH) and oxygen-tolerant membrane-bound (MBH) enzymes. For three PHs and four MBHs from six bacterial species, structural features of the nickel-iron active site of hydrogen turnover and of the iron-sulfur clusters functioning in electron transfer were determined using X-ray absorption spectroscopy (XAS). Fe-XAS indicated surp

Electronic and molecular structures of the active-site H-cluster in [FeFe]-hydrogenase determined by site-selective X-ray spectroscopy and quantum chemical calculations

The [FeFe]-hydrogenase (HydA1) from green algae is the minimal enzyme for efficient biological hydrogen (H2) production. Its active-site six-iron center (H-cluster) consists of a cubane, [4Fe4S]H, cysteine-linked to a diiron site, [2Fe]H. We utilized the spin-polarization of the iron Kβ X-ray fluorescence emission to perform site-selective X-ray absorption experiments for spectral discrimination o

Bridging-hydride influence on the electronic structure of an [FeFe] hydrogenase active-site model complex revealed by XAES-DFT

Two crystallized [FeFe] hydrogenase model complexes, 1 = (μ-pdt)[Fe(CO)2(PMe3)]2 (pdt = SC1H 2C2H2C3H2S), and their bridging-hydride (Hy) derivative, [1Hy]+ = [(μ-H)(μ-pdt)[Fe(CO)2 (PMe 3)]2]+ (BF4-), were studied by Fe K-edge X-ray absorption and emission spectroscopy, supported by density functional theory. Structural changes in [1Hy]+ compared to 1 involved small bond elongations (

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

Structure of the molybdenum site in YedY, a sulfite oxidase homologue from escherichia coli

YedY from Escherichia coli is a new member of the sulfite oxidase family of molybdenum cofactor (Moco)-containing oxidoreductases. We investigated the atomic structure of the molybdenum site in YedY by X-ray absorption spectroscopy, in comparison to human sulfite oxidase (hSO) and to a MoIV model complex. The K-edge energy was indicative of MoV in YedY, in agreement with X-and Q-band electron para

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 S0 state of the water oxidizing complex in photosystem II : pH dependence of the EPR split signal induction and mechanistic implications

Water oxidation in photosystem II is catalyzed by the CaMn4 cluster. The electrons extracted from the CaMn4 cluster are transferred to P680+ via the redox-active tyrosine residue D1-Tyr161 (YZ). The oxidation of YZ is coupled to a deprotonation creating the neutral radical YZ•. Light-induced oxidation of YZ is possible down to extreme temperatures. This can be observed as a split EPR signal from Y

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

Concentration of citrus fruit juices in membrane pouches with solar energy Part 1 : How solar drying setup and juice pretreatment determine the drying flux

The aim of this study was to investigate how solar drying setup and choice of juice pretreatment determine the drying flux in a fruit juice concentration process called solar assisted pervaporation. With this process, hygienic membrane pouches and solar energy are used to concentrate and preserve fruit juices. In this study, the feasibility of concentrating citrus (tangerine) juice into marmalade

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

Säkerhetsutbildningar och säkerhetskulturarbete vid forskningsanläggningar med strålningsrisker och många tillfälliga internationella användare – ett fortsättningsprojekt

Det övergripande syftet med detta projekt har varit att ge ett konkret underlag somkan användas som stöd för att utveckla välfungerande kortare säkerhetsutbildningar i säkerhetskritiska verksamheter.Utgångspunkten har varit forskningsanläggningarna MAX IV och EuropeanSpallation Source (ESS) där forskare, dvs användare, från hela världen vistas tillfälligt för att genomföra experiment. Användarna k

Nomenclature and semantic descriptions of ulcerative and inflammatory lesions seen in Crohn’s disease in small bowel capsule endoscopy : An international Delphi consensus statement

Background: In the medical literature, the nomenclature and descriptions (ND) of small bowel (SB) ulcerative and inflammatory (U-I) lesions in capsule endoscopy (CE) are scarce and inconsistent. Inter-observer variability in interpreting these findings remains a major limitation in the assessment of the severity of mucosal lesions, which can impact negatively on clinical care, training and researc