Deciphering molecular spectra of syn- and gauche-propanal

The present work features the measurements and detailed analyses of the rotational and ro-vibrational spectra of propanal, or propionaldehyde (CH3CH2CHO). Broadband spectra were taken with (sub-)millimeter wavelength spectrometers in the frequency regions of 75-129 GHz and 170-500 GHz in Cologne. Additional far infrared spectra were recorded with a synchrotron-based Fourier-transform infrared spectrometer in the region of 80-700 cm-1 (SOLEIL synchrotron - AILES A beamline, Paris). Propanal has two stable conformers, referred to as the syn- and gauche-forms. They differ mainly in the orientation of the aldehyde group (-CHO) with respect to the rigid carbon atom framework of the molecule. The rotational lines of syn-propanal show splittings due to internal rotation of the methyl group (-CH3) and are fit with Groner's ERHAM program. The spectrum of gauche-propanal shows somewhat larger tunneling splittings originating from two stable energetically degenerate conformers and are analyzed with Pickett's SPFIT program. In summary, rotational spectra of v=0, v24=1, v23=1, v15=1, v24=2, and v24=v23=1 vibrational states of syn-propanal as well as v=0 and v24=1 of gauche-propanal are studied. The fundamental vibrational frequency v24 of gauche-propanal is redetermined to 68.75037(30) cm-1 on account of observed Coriolis interactions and Fermi resonances in the rotational analysis. Another main result is the reassignment of the fundamental band v24 of syn-propanal in the far infrared spectrum at 133.9754525(39) cm-1. The millimeter- millimeter-wave double resonance experimental technique is established in Cologne using a newly assembled spectrometer allowing to unambiguously assign lines owing to the Autler-Townes effect. Furthermore, the implementation of a double modulation technique (modulation of both the pump and probe sources) allows for baseline- and confusion-free spectra containing only the line(s) of interest

Book Discussion

Book discussion of Persepolis: The Story of a Childhood by Marjane Satrapi. Faculty panelists include Sandra Gandy, JoAnne Smith, and Jason Zingsheim with Provost Terry Allison as moderator

GERMANIUM DICARBIDE: EVIDENCE FOR A T−SHAPED GROUND STATE STRUCTURE

The preferred equilibrium structure of germanium dicarbide (GeC$_2$) has been an open question for decades: while high-level quantum chemical calculations predict an L-shaped ground state structure, the very flat potential energy surface of the species prevents a T-shaped structure from being entirely ruled out$^1$. By recording for the first time the rotational spectrum of GeC$_2$ using sensitive microwave and millimeter techniques, we establish that the molecule adopts a vibrationally-averaged T-shaped structure in the ground state. From isotopic substitution of 14 isotopologues, a precise $r_0$ structure has been derived. This structural work should serve as an important benchmark for future calculations._x000d_ _x000d_ $^1$ Sari et al., textit{J. Chem. Phys.} textbf{117} 10008 (2002

THE (SUB-)MILLIMETER-WAVE SPECTRUM OF PROPANAL

The microwave spectrum of propanal, also known as propionaldehyde, CH$_3$CH$_2$CHO, has been investigated in the laboratory already since 1964$^1$ and has also been detected in space$^2$. Recently, propanal was detected with the Atacama Large Millimeter/submillimeter Array (ALMA), Protostellar Interferometric Line Survey (PILS)$^3$. The high sensitivity and resolution of ALMA indicated small discrepancies between observed and predicted rotational spectra of propanal. As higher accuracies are desired the spectrum of propanal was measured up to 500$,$GHz with the Cologne (Sub-)Millimeter spectrometer. Propanal has two stable conformers, textit{syn} and textit{gauche}, which differ mainly in the rotation of the aldehyd group with respect to the rigid C-atom framework of the molecule. We extensively studied both of them. The lower textit{syn}-conformer shows small splittings caused by the internal rotation of the methyl group, whereas the spectrum of textit{gauche}-propanal is complicated due to the tunneling rotation interaction from two stable degenerate conformers. Additionally, we analyzed vibrationally excited states._x000d_ _x000d_ $^1$ Butcher et al., textit{J. Chem. Phys.} textbf{40} 6 (1964)_x000d_ _x000d_ $^2$ Hollis et al., textit{Astrophys. J.} textbf{610} L21 (2004)_x000d_ _x000d_ $^3$ Lykke et al., textit{A&A} textbf{597} A53 (2017

ADR (Alternative Dispute Resolution) nach japanischem Recht unter besonderer Berücksichtigung der Beilegung ziviler Streitigkeiten über Umweltverschmutzung

Die vorliegende Dissertation beschäftigt sich mit dem Thema „ADR (Alternative Dispute Resolution) nach japanischem Recht – unter besonderer Berücksichtigung ziviler Streitigkeiten über Umweltverschmutzung“. Auf den ersten Blick könnte man versucht sein, die Arbeit unter das Schlagwort „Umweltmediation in Japan“ einzuordnen. Hiervon ist jedoch Abstand zu nehmen, da sich das System alternativer Streitbeilegung Japans grundlegend von der Umweltmediation Deutschlands unterscheidet, die in erster Linie auf die Lösung von Disputen auf politisch-administrativer Ebene abzielt und der es bisher an einer rechtlichen Einbindung fehlt. In der vorliegenden Arbeit wird das japanische System alternativer Streitbeilegung unter besonderer Berücksichtigung der Beilegung von zivilrechtlichen Umweltdisputen umfassenden dargestellt und kritisch hinterfragt. Aufgrund der Tatsache, dass ein System alternativer Streitbeilegung nur in Relation zu der herkömmlichen Form der Konfliktlösung bewertet werden kann, werden zunächst der japanische Zivilprozess und die Probleme der Rechtspflege analysiert. Es folgt eine umfassende Darstellung der ADR-Landschaft. Gegenwärtigen Formen der ADR werden systematisch nach Verfahrensstruktur, Einrichtungsorganen, Wirkung der Streitlösung und den unterschiedlichen Verfahrenszielen vorgestellt. Trends der Reformbestrebungen werden analysiert. Den Schwerpunkt der Arbeit bildet die Darstellung der komplexen Möglichkeiten zur Beilegung von zivilen Streitigkeiten über Umweltverschmutzung. Ein Abriss in die Geschichte der Umweltverschmutzung und Umweltgesetzgebung leitet in die Thematik ein. Es folgt eine Skizierung der Beilegung ziviler Streitigkeiten über Umweltverschmutzung vor den staatlichen Gerichten anhand der Rechtsprechung ausgewählter Umweltprozesse. Die herausgearbeiteten Mittel herkömmlichen ADR-Verfahren werden auf ihre Anwendbarkeit im Umweltsektor hin überprüft. Im Zentrum der Arbeit steht die detaillierte Analyse des Gesetzes bzw. des Systems zur außergerichtlichen Beilegung von Streitigkeiten über Umweltverschmutzung. Die Analyse der unterschiedlichen Verfahrenstypen, der Organe und Kosten der Streitbeilegung, der Reformen sowie der durch die fast dreißigjährige Praxis gewonnenen Erfahrungen und Erfolge des Systems liefert Erkenntnisse, die möglicherweise auch Anregungen für die Bewältigung von Umweltstreitigkeiten in Deutschland geben mag

Insulin-stimulated phosphorylation of protein phosphatase 1 regulatory subunit 12B revealed by HPLC-ESI-MS/MS

BACKGROUND: Protein phosphatase 1 (PP1) is one of the major phosphatases responsible for protein dephosphorylation in eukaryotes. Protein phosphatase 1 regulatory subunit 12B (PPP1R12B), one of the regulatory subunits of PP1, can bind to PP1cδ, one of the catalytic subunits of PP1, and modulate the specificity and activity of PP1cδ against its substrates. Phosphorylation of PPP1R12B on threonine 646 by Rho kinase inhibits the activity of the PP1c-PPP1R12B complex. However, it is not currently known whether PPP1R12B phosphorylation at threonine 646 and other sites is regulated by insulin. We set out to identify phosphorylation sites in PPP1R12B and to quantify the effect of insulin on PPP1R12B phosphorylation by using high-performance liquid chromatography-electrospray ionization-tandem mass spectrometry. RESULTS: 14 PPP1R12B phosphorylation sites were identified, 7 of which were previously unreported. Potential kinases were predicted for these sites. Furthermore, relative quantification of PPP1R12B phosphorylation sites for basal and insulin-treated samples was obtained by using peak area-based label-free mass spectrometry of fragment ions. The results indicate that insulin stimulates the phosphorylation of PPP1R12B significantly at serine 29 (3.02 ± 0.94 fold), serine 504 (11.67 ± 3.33 fold), and serine 645/threonine 646 (2.34 ± 0.58 fold). CONCLUSION: PPP1R12B was identified as a phosphatase subunit that undergoes insulin-stimulated phosphorylation, suggesting that PPP1R12B might play a role in insulin signaling. This study also identified novel targets for future investigation of the regulation of PPP1R12B not only in insulin signaling in cell models, animal models, and in humans, but also in other signaling pathways

Rotational spectrum and intramolecular hydrogen bonding in 1,2-butanedithiol

Producción CientíficaThe jet-cooled rotational spectrum of 1,2-butanedithiol was observed in the frequency region 2–8 GHz. Two conformers were detected for the molecule, corresponding to anti- and gauche-carbon molecular skeletons, both featuring a gauche arrangement of the two thiol groups. All 13C and 34S monosubstituted isotopologues were additionally assigned in natural abundance for the most stable anti isomer, while only the two 34S species were detected for the weaker gauche conformation. The structural analysis included ground-state effective structures, isotopic substitution coordinates, B3LYP-D3(BJ) density functional molecular orbital calculations and non-covalent interactions mapping with NCIPlot. The structural data confirm that the two thiol groups synchronize their orientation either parallel or antiparallel to support intramolecular S–H⋯S weak hydrogen bonding, reminiscent of the intramolecular hydrogen bond networks observed in adjacent alcohol groups. DFT calculations on 1,2-butanediol and 1,2-ethanedithiol offered structural comparisons with the title compound.MICIU-FEDER (grant PGC2018- 098561-B-C22) and JCyL (grant VA056G18

Conformational dynamics in TRPV1 channels reported by an encoded coumarin amino acid

TRPV1 channels support the detection of noxious and nociceptive input. Currently available functional and structural data suggest that TRPV1 channels have two gates within their permeation pathway: one formed by a 0bundle-crossing0 at the intracellular entrance and a second constriction at the selectivity filter. To describe conformational changes associated with channel gating, the fluorescent non-canonical amino acid coumarin-tyrosine was genetically encoded at Y671, a residue proximal to the selectivity filter. Total internal reflection fluorescence microscopy was performed to image the conformational dynamics of the channels in live cells. Photon counts and optical fluctuations from coumarin encoded within TRPV1 tetramers correlates with channel activation by capsaicin, providing an optical marker of conformational dynamics at the selectivity filter. In agreement with the fluorescence data, molecular dynamics simulations display alternating solvent exposure of Y671 in the closed and open states. Overall, the data point to a dynamic selectivity filter that may serve as a gate for permeation