Tagungsbericht 5. Studientag Literatur- und Wissenschaftsgeschichte

Im fünften Jahr in Folge luden das Institut für Deutsche und Niederländische Philologie der Freien Universität Berlin, das Max-Planck-Institut für Wissenschaftsgeschichte und das Exzellenzcluster 16 der Universität Konstanz am 10. Juli 2010 ein zu einem für alle Interessierten offenen Forum für NachwuchswissenschaftlerInnen, die sich im Feld von Literature and Science betätigen und vorläufige Ergebnisse noch nicht abgeschlossener Arbeiten zur Diskussion stellen möchten

Enhanced Extrastriate Activation during Observation of Distorted Finger Postures

Hand and finger postures of other people are important body language cues that strongly contribute to the observer's decision about the person's intentions, thoughts, and attentional state. We compared neuromagnetic cortical activation elicited by color images of natural and distorted finger postures. The distorted postures contained computer-deformed joint angles and thereby easily caught the observer's attention. From about 260 msec onwards, extrastriate occipital areas of both hemispheres were activated more strongly by distorted than natural finger postures. We interpret this result as an early topdown effect of emotional valence on the processing of unusual hand shapes in the extrastriate visual cortex.Peer reviewe

Crystal structure of a novel (R)-selective amine transaminase and approaches to broaden its substrate scope by rational engineering

We recently identified a novel (R)-selective amine transaminase (ATA); now we want to broaden its substrate scope since ATAs are promising biocatalysts for the production of chiral amines [1]. In general, aminotransferases are pyridoxal-5′-phosphate (PLP)-dependent enzymes, which reversibly catalyze the transfer of an amino group from an amino donor to a ketone or aldehyde, resulting in the formation of chiral amines. The conversion of bulky ketones to amines is especially interesting because they serve as drug-precursors. In most cases, bulky ketones are not naturally converted. For this reason, protein engineering methods are applied. There are two approaches: random and rational. While we also use the random approach, rational engineering seems to be more effective for our purpose. We use the protein crystal structure to predict impactful amino acid exchanges to improve transamination activity. In this work, we present the characteristics of our novel (R)-selective ATA and show its crystal structure with the PLP bound to the active site lysine. Furthermore, we compare our ATA to existing (R)‑selective ATA structures [2] and explain our approach to broaden the substrate scope by rational engineering. Please click Additional Files below to see the full abstract

(3R,4R,5S)-4-Hydr­oxy-3-methyl-5-[(2S,3R)-3-methyl­pent-4-en-2-yl]-4,5-dihydro­furan-2(3H)-one

The relative configuration of the title compound, C11H18O3, which was synthesized using a catalytic asymmetric Gosteli–Claisen rearrangement, a diastereoselective reduction with K-Selectride and an Evans aldol addition, was corroborated by single-crystal X-ray diffraction analysis. The five-membered ring has an envelope conformation with a dihedral angle of 29.46 (16)° between the coplanar part and the flap (the hydr­oxy-bearing ring C atom). In the crystal, mol­ecules are connected via bifurcated O—H⋯(O,O) hydrogen bonds, generating [010] chains

N1 responses to images of hands in occipito-temporal event-related potentials

Hands, much like faces, convey social information, instructions and intentions to an observer. While the neural processes of face perception have been widely studied, it was only recently that fMRI identified occipito-temporal areas sensitive to static images of hands as body parts. To complement these studies with fine-grained timing information, we measured event-related EEG potentials (ERPs) from 33 subjects who were presented with static images of hands versus faces, whole bodies, and inanimate objects as controls. Already at N1 latency, ~ 170 ms, hand-related ERP patterns were manifest in two results: (1) significant differences in amplitudes for images of hands versus bodies in occipito-temporal N1 responses; (2) left lateralization of responses to images of hands, and also of the difference waveforms (hands minus bodies), quantifying hand-related responses. In line with fMRI studies of hand-sensitive areas distinct from extrastriate body area (EBA), the current findings provide electrophysiological evidence for hand-sensitive brain activation, occurring at a similarly early latency as N1 responses to faces

Lateralized occipito-temporal N1 responses to images of salient distorted finger postures

For humans as social beings, other people’s hands are highly visually conspicuous. Exceptionally striking are hands in other than natural configuration which have been found to elicit distinct brain activation. Here we studied response strength and lateralization of this activation using event-related potentials (ERPs), in particular, occipitotemporal N1 responses as correlates of activation in extrastriate body area. Participants viewed computer-generated images of hands, half of them showing distorted fingers, the other half showing natural fingers. As control stimuli of similar geometric complexity, images of chairs were shown, half of them with distorted legs, half with standard legs. The contrast of interest was between distorted and natural/standard stimuli. For hands, stronger N1 responses were observed for distorted (vs natural) stimuli from 170 ms post stimulus. Such stronger N1 responses were found for distorted hands and absent for distorted chairs, therefore likely unrelated to visuospatial processing of the unusual distorted shapes. Rather, N1 modulation over both hemispheres - but robustly right-lateralized - could reflect distorted hands as emotionally laden stimuli. The results are in line with privileged visual processing of hands as highly salient body parts, with distortions engaging neural resources that are especially activated for biological stimuli in social perception

Lateral-torsional Buckling of Ferritic Stainless Steel Beams in Case of Fire

audience: researcherThis work presents a numerical study of the behaviour of ferritic stainless steel Ibeams subjected to lateral-torsional buckling and compares the obtained results with the beam design curves of Eurocode 3. New formulae, for the lateraltorsional buckling, that approximate better the real behaviour of ferritic stainless steel structural elements in case of fire are proposed. These new formulae were based on numerical simulations using the program SAFIR, which was modified to take into account the material properties of the stainless steel

(±)-syn-Isopropyl 4-(1,1,1,3,3,3-hexa­fluoro­propan-2-yl­oxy)-1-hydr­oxy-3-methyl-2-(prop-1-yn­yl)cyclo­pent-2-ene­carboxyl­ate

The title compound, C16H18F6O4, was obtained through an unprecedented one-pot reaction sequence involving a Gosteli–Claisen rearrangement and a cyclo­isomerization. The constitution and relative configuration were determined by single-crystal X-ray diffraction analysis. In the crystal, mol­ecules are connected via O—H ⋯ O hydrogen bonds

(2SR,3SR)-Isopropyl 3-{[dimeth­yl(phenyl)­sil­yl]meth­yl}-2-hy­droxy-2-vinyl­pent-4-enoate

The relative configuration of the title compound, C19H28O3Si, which was synthesized using a dienolate-[2,3]-Wittig rearrangement, was corroborated by single-crystal X-ray diffraction analysis. The Si—C bond distances are in the range 1.858 (2)–1.880 (2) Å and an intra­molecular O—H⋯O hydrogen bond helps to stabilize the mol­ecular conformation