TY - JOUR A1 - Gonzáles-Diaz, P. F. A1 - Kasper, Uwe A1 - Rainer, Martin T1 - 2-Dimensional dilatonic gravity from multidimensional Einstein gravity Y1 - 1998 ER - TY - JOUR A1 - Dzambaski, Zdravko A1 - Markovic, Rade A1 - Kleinpeter, Erich A1 - Baranac-Stojanovic, Marija T1 - 2-Alkylidene-4-oxothiazolidine S-oxides - synthesis and stereochemistry JF - Tetrahedron N2 - A series of 5-unsubstituted and 5-substituted 2-alkylidene-4-oxothiazolidine-S-oxides were synthesized by the sulfur-oxidation with m-CPBA. The stereochemistry of 5-substituted sulfoxides was determined by means of NMR spectroscopy and DFT theoretical calculations. It was found that the thermodynamically less stable anti-isomer was initially formed in the course of the oxidation, but it underwent epimerization to the mixture enriched in the more stable syn-isomer, during the work-up process. The higher stability of syn-isomers is ascribed to the stronger hyperconjugative sigma(C-H)->sigma*(S-O) interaction versus the weaker sigma(C-C)->sigma*(S-O) delocalization in their anti-counterparts and to the existence of intramolecular 1,5-CH center dot center dot center dot C hydrogen bonds. KW - 2-Alkylidene-4-oxothiazolidine KW - Sulfoxide KW - Diastereoselectivity KW - Density functional calculations KW - CH center dot center dot center dot O hydrogen bonds Y1 - 2013 U6 - https://doi.org/10.1016/j.tet.2013.05.087 SN - 0040-4020 VL - 69 IS - 31 SP - 6436 EP - 6447 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Strehmel, Veronika A1 - Rexhausen, Hans A1 - Strauch, Peter T1 - 2,2,6,6-Tetramethylpiperidine-1-yloxyl bound to the imidazolium ion by an acetamido group for investigation of ionic liquids N2 - New spin probes bearing the 2,2,6,6-tetramethylpiperidine-1-yloxyl covalently bound to the imidazolium ion via a methylene spacer and an amide group are synthesized. If the anion is bis(trifluoromethylsulfonylimide) instead of iodide, the new spin probe has a similar structure as that of an ionic liquid. Nevertheless, the new spin probes are useful tools to investigate ionic liquids. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/00404039 U6 - https://doi.org/10.1016/j.tetlet.2009.11.124 SN - 0040-4039 ER - TY - JOUR A1 - Schmidt, Bernd A1 - Riemer, Martin A1 - Karras, Manfred T1 - 2,2 '-Biphenols via protecting group-free thermal or microwave-accelerated suzuki-miyaura coupling in water JF - The journal of organic chemistry N2 - User-friendly protocols for the protecting group-free synthesis of 2,2'-biphenols via Suzuki-Miyaura coupling of o-halophenols and o-boronophenol are presented. The reactions proceed in water in the presence of simple additives such as K2CO3, KOH, KF, or TBAF and with commercially available Pd/C as precatalyst. Expensive or laboriously synthesized ligands or other additives are not required. In the case of bromophenols, efficient rate acceleration and short reaction times were accomplished by microwave irradiation. Y1 - 2013 U6 - https://doi.org/10.1021/jo401398n SN - 0022-3263 VL - 78 IS - 17 SP - 8680 EP - 8688 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Kammer, Stefan A1 - Kelling, Alexandra A1 - Baier, Heiko A1 - Mickler, Wulfhard A1 - Dosche, Carsten A1 - Rurack, Knut A1 - Kapp, Andreas A1 - Lisdat, Fred A1 - Holdt, Hans-Jürgen T1 - 2,11-dialkylated 1,12-diazaperylene copper(I) complexes : first supramolecular column assemblies by pi-pi stacking between homoleptic tetrahedral metal complexes, exhibiting low-energy MLCT transitions N2 - 2,11-Dialkylated 1,12-diazaperylenes (alkyl = Me, Et, iPr) dmedap, detdap and dipdap have been synthesized by reductive cyclization of 3,3-dialkylated 1,1-biisoquinolines 3a-c, resulting in the first copper(I) complexes of a large- surface ligand. The new copper(I) complexes show low-energy MLCT absorptions unprecedented for bis(-diimin)copper(I) complexes. The solid structures of the complexes[Cu(dipdap)2]BF4·CH2Cl2·1.5H2O, [Cu(dipdap)2]OTf·CH2Cl2, [Cu(dipdap)2]I·C2H4Cl2·THF·2H2O, [Cu(dmedap)2]OTf and [Cu(dipdap)2]AQSO3·H2O (AQSO3 = sodium 9,10-dihydro-9,10-dioxo-2- anthracenesulfonate) are reported. In [Cu(dipdap)2]BF4·CH2Cl2·1.5H2O, each copper(I) complex cation interacts with two others by - stacking interactions forming a novel supramolecular column structural motif running along the crystallographic c axis. In the crystalline compound [Cu(dipdap)2]AQSO3·H2O, aggregation between two complex cations and two additional anions by - stacking interactions is observed, leading to a tetrameric assembly. Furthermore, the three complex compounds [Cu(L)2]BF4 (L = dmedap, detdap, dipdap) were tested for sensory applications in aqueous buffer solutions in electrochemical studies of the complex immobilized on glassy carbon electrodes. Y1 - 2009 UR - http://www3.interscience.wiley.com/journal/27721/home U6 - https://doi.org/10.1002/ejic.200900695 SN - 1434-1948 ER - TY - JOUR A1 - Dzhunushaliev, Vladimir A1 - Schmidt, Hans-Jürgen T1 - 2+2-decomposable solutions of weyl gravity BT - Zwei plus zwei-decomposable solutions of wey gravity Y1 - 1999 ER - TY - JOUR A1 - Schreiber, Ulrike A1 - Hosemann, Benjamin A1 - Beuermann, Sabine T1 - 1H,1H,2H,2H-Perfluorodecyl-Acrylate-Containing block copolymers from ARGET ATRP JF - Macromolecular chemistry and physics N2 - Block copolymers of 1H,1H,2H,2H-perfluorodecyl acrylate (AC8) were obtained from ARGET ATRP. To obtain block copolymers of low dispersity the PAC8 block was synthesized in anisole with a CuBr(2)/PMDETA catalyst in the presence of tin(II) 2-ethylhexanoate as a reducing agent. The PAC8 block was subsequently used as macroinitiator for copolymerization with butyl and tert-butyl acrylate carried out in scCO(2). To achieve catalyst solubility in CO(2) two fluorinated ligands were employed. The formation of block copolymers was confirmed by size exclusion chromatography and DSC. KW - atom transfer radical polymerization (ATRP) KW - block copolymers KW - fluoropolymers KW - supercritical carbon dioxide Y1 - 2011 U6 - https://doi.org/10.1002/macp.201000307 SN - 1022-1352 VL - 212 IS - 2 SP - 168 EP - 179 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Starke, Ines A1 - Koch, Andreas A1 - Holdt, Hans-Jürgen A1 - Kleinpeter, Erich T1 - 1H, 13C, and 15N NMR study of the solution structure of metabridged bis(benzo-15-crown-5-ether)s Y1 - 1995 ER - TY - JOUR A1 - Hilfert, Liane A1 - Sarodnick, Gerhard A1 - Kempter, Gerhard A1 - Kleinpeter, Erich T1 - 1H, 13C and 15 N NMR study and molecular modelling of 2,3- disubstituted quinoxalines with sterically hinderered aromatic and heteroaromatic substituents Y1 - 1998 ER - TY - JOUR A1 - Lehmann, J. A1 - Kleinpeter, Erich T1 - 1H NMR Lanthanideinduced Shift (LIS) investigations of highly flexible molecules : a new approach ; Part II Y1 - 1993 ER - TY - JOUR A1 - Lehmann, J. A1 - Kleinpeter, Erich T1 - 1H NMR Lanthanideinduced Shift (LIS) investigations of highly flexible molecules : a new approach Y1 - 1993 ER - TY - JOUR A1 - Lehmann, J. A1 - Kleinpeter, Erich T1 - 1H NMR lanthanide-induced shift investigations of highly flexible molecules, part III. Applications to alcohols, aldehydes, esters and amines Y1 - 1995 ER - TY - JOUR A1 - Poleschner, Helmut A1 - Heydenreich, Matthias T1 - 1H and 13C NMR Spectra and One-Bond 13C,13C Coupling Constants of 2-Alken-4-yn-1-ols, (E)-2-Alken-4-yn-1-yl Acetates and (E)-2-Alken-4-yn-1-als Y1 - 1997 ER - TY - JOUR A1 - Guillemoteau, Julien A1 - Simon, Francois-Xavier A1 - Lück, Erika A1 - Tronicke, Jens T1 - 1D sequential inversion of portable multi-configuration electromagnetic induction data JF - Near surface geophysics N2 - We present an algorithm that performs sequentially one-dimensional inversion of subsurface magnetic permeability and electrical conductivity by using multi-configuration electromagnetic induction sensor data. The presented method is based on the conversion of the in-phase and out-of-phase data into effective magnetic permeability and electrical conductivity of the equivalent homogeneous half-space. In the case of small-offset systems, such as portable electromagnetic induction sensors, for which in-phase and out-of-phase data are moderately coupled, the effective half-space magnetic permeability and electrical conductivity can be inverted sequentially within an iterative scheme. We test and evaluate the proposed inversion strategy using synthetic and field examples. First, we apply it to synthetic data for some highly magnetic environments. Then, the method is tested on real field data acquired in a basaltic environment to image a formation of archaeological interest. These examples demonstrate that a joint interpretation of in-phase and out-of-phase data leads to a better characterisation of the subsurface in magnetic environments such as volcanic areas. Y1 - 2016 U6 - https://doi.org/10.3997/1873-0604.2016029 SN - 1569-4445 SN - 1873-0604 VL - 14 SP - 423 EP - 432 PB - Wiley-VCH CY - Houten ER - TY - JOUR A1 - Guillemoteau, Julien A1 - Lück, Erika A1 - Tronicke, Jens T1 - 1D inversion of direct current data acquired with a rolling electrode system JF - Journal of applied geophysics N2 - Direct current systems employing a kinematic surveying strategy allow to analyze the electrical resistivity of the subsurface for large areas (i.e., several hectares). Typical applications are found in precision agriculture, archaeological prospecting and soil sciences. With the typical survey setting, the collected data sets are often characterized by a rather high level of noise and a rather coarse lateral sampling compared to data acquired with fixed electrodes. We therefore present an efficient one-dimensional inversion approach in which we put special attention on modeling the effects of noise. We apply this method to data recorded with a five-offset equatorial dipole-dipole system employing rolling electrodes. By performing several synthetic tests with realistic noise levels, we found that the considered five-configuration soundings allow for a reliable imaging of two-layer cases in the uppermost two meters of the subsurface, where the subsurface can be assumed to follow a horizontally layered geometry within 3 m around the system. By analyzing the corresponding sensitivity functions, we also show that the equatorial dipole-dipole array is relatively well suited for a 1D inversion approach compared to standard in-line electrode arrays. To illustrate this aspect, we show that our method can provide results similar to those obtained with a 2D Wenner imaging procedure for data recorded across a well-constrained 2D target. We finally apply our method to a large five-offset data set acquired in an agricultural study. The final pseudo-3D model of electrical resistivity is in accordance with borehole data available for the surveyed area. Our results demonstrate the applicability and the versatility of the presented inversion approach for large-scale data sets as they are typically collected with such rolling electrode systems. (C) 2017 Elsevier B.V. All rights reserved. Y1 - 2017 U6 - https://doi.org/10.1016/j.jappgeo.2017.09.010 SN - 0926-9851 SN - 1879-1859 VL - 146 SP - 167 EP - 177 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Poleschner, Helmut A1 - Heydenreich, Matthias A1 - Schilde, Uwe T1 - 13C, 19F and 77Se NMR study of vicinal (E)-fluoro(organylseleno)olefins and [(E)- fluoroalkenyl]diorganylselenonium salts N2 - Selenides of the type R1Se-EMe3 (E = Si, Ge, Sn, Pb) react with xenon difluoride by cleavage of the Se-E bond to yield the R1Se-F intermediate and the fluorides Me3E-F, whereas the Se-C bond in PhSe-tBu (E = C) is stable against XeF2. The presence of R1Se-F intermediates is confirmed by addition to acetylenes (4-octyne, 3-hexyne). Thus, the fluoroselenenylation of acetylenes gives fluoro(organylseleno)olefins in preparative yields. In the cases of E = Si, Ge, Sn, and Pb, aryl and n-alkyl groups are suitable as the substituent R1. The X-ray crystal structural analysis of (E)-3- (p-carboxyphenylseleno)-4-fluorohex-3-ene - the first example of an uncharged fluoroselenoolefin synthesized from p- EtO2C-C6H4-Se-SnMe3, XeF2, and 3-hexyne followed by an ester hydrolysis - shows that the addition of the selenenylfluoride intermediate to the acetylene proceeds via a trans-addition, as is known for the R2Se2-XeF2 reagents. Y1 - 2000 ER - TY - JOUR A1 - Poleschner, Helmut A1 - Heydenreich, Matthias T1 - 13C NMR chemical shifts of unbranched 2-Alkyn-1-ols, w-Alkyn-1-ols and "internal" Alkyn-1-ols Y1 - 1995 ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Thomas, Steffen A1 - Fischer, G. T1 - 13C and 15N NMR study of 1,2,4-Triazolo[1,5-a]pyrimidines with one tautomerism-introducing substituent Y1 - 1995 ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Koch, Andreas A1 - Fischer, G. A1 - Askolin, C.-P. T1 - 13 C NMR, 15 N NMR and quantum-chemical study of the tautomerism of 2-substituted 5-ME-7-OH-1,2,4-triazolo[1,5- a]pyrimidines Y1 - 1997 ER - TY - JOUR A1 - Thomas, Steffen A1 - Brühl, Iris A1 - Heilmann, Dieter A1 - Kleinpeter, Erich T1 - 13 C NMR Chemical shift calculations for some substituted pyridines - a comparative consideration Y1 - 1997 ER - TY - JOUR A1 - Calo, Camilla A1 - Henne, Paul D. A1 - Eugster, Patricia A1 - van Leeuwen, Jacqueline A1 - Gilli, Adrian A1 - Hamann, Yvonne A1 - La Mantia, Tommaso A1 - Pasta, Salvatore A1 - Vescovi, Elisa A1 - Tinner, Willy T1 - 1200 years of decadal-scale variability of mediterranean vegetation and climate at Pantelleria Island, Italy JF - The Holocene : an interdisciplinary journal focusing on recent environmental change N2 - A new sedimentary sequence from Lago di Venere on Pantelleria Island, located in the Strait of Sicily between Tunisia and Sicily was recovered. The lake is located in the coastal infra-Mediterranean vegetation belt at 2 m a.s.l. Pollen, charcoal and sedimentological analyses are used to explore linkages among vegetation, fire and climate at a decadal scale over the past 1200 years. A dry period from ad 800 to 1000 that corresponds to the Medieval Warm Period' (WMP) is inferred from sedimentological analysis. The high content of carbonate recorded in this period suggests a dry phase, when the ratio of evaporation/precipitation was high. During this period the island was dominated by thermophilous and drought-tolerant taxa, such as Quercus ilex, Olea, Pistacia and Juniperus. A marked shift in the sediment properties is recorded at ad 1000, when carbonate content became very low suggesting wetter conditions until ad 1850-1900. Broadly, this period coincides with the Little Ice Age' (LIA), which was characterized by wetter and colder conditions in Europe. During this time rather mesic conifers (i.e. Pinus pinaster), shrubs and herbs (e.g. Erica arborea and Selaginella denticulata) expanded, whereas more drought-adapted species (e.g. Q. ilex) declined. Charcoal data suggest enhanced fire activity during the LIA probably as a consequence of anthropogenic burning and/or more flammable fuel (e.g. resinous Pinus biomass). The last century was characterized by a shift to high carbonate content, indicating a change towards drier conditions, and re-expansion of Q. ilex and Olea. The post-LIA warming is in agreement with historical documents and meteorological time series. Vegetation dynamics were co-determined by agricultural activities on the island. Anthropogenic indicators (e.g. Cerealia-type, Sporormiella) reveal the importance of crops and grazing on the island. Our pollen data suggest that extensive logging caused the local extinction of deciduous Quercus pubescens around ad1750. KW - central Mediterranean KW - fire history KW - "Little Ice Age' (LIA) KW - "Medieval Warm Period' (MWP) KW - Pinus pinaster KW - Quercus ilex KW - Quercus pubescens KW - vegetation history Y1 - 2013 U6 - https://doi.org/10.1177/0959683613493935 SN - 0959-6836 SN - 1477-0911 VL - 23 IS - 10 SP - 1477 EP - 1486 PB - Sage Publ. CY - London ER - TY - JOUR A1 - Denz, Rebekka A1 - Dubrau, Alexander A1 - Riemer, Nathanael T1 - 100th anniversary of Tel Aviv Y1 - 2009 SN - 1614-6492 ER - TY - JOUR A1 - Sammoud, Senda A1 - Nevill, Alan Michael A1 - Negra, Yassine A1 - Bouguezzi, Raja A1 - Chaabene, Helmi A1 - Hachana, Younes T1 - 100-m Breaststroke Swimming Performance in Youth Swimmers BT - the predictive value of anthropometrics JF - Pediatric exercise science N2 - This study aimed to estimate the optimal body size, limb segment length, and girth or breadth ratios of 100-m breaststroke performance in youth swimmers. In total, 59 swimmers [male: n= 39, age = 11.5 (1.3) y; female: n= 20, age = 12.0 (1.0) y] participated in this study. To identify size/shape characteristics associated with 100-m breaststroke swimming performance, we computed a multiplicative allometric log-linear regression model, which was refined using backward elimination. Results showed that the 100-m breaststroke performance revealed a significant negative association with fat mass and a significant positive association with the segment length ratio (arm ratio = hand length/forearm length) and limb girth ratio (girth ratio = forearm girth/wrist girth). In addition, leg length, biacromial breadth, and biiliocristal breadth revealed significant positive associations with the 100-m breaststroke performance. However, height and body mass did not contribute to the model, suggesting that the advantage of longer levers was limb-specific rather than a general whole-body advantage. In fact, it is only by adopting multiplicative allometric models that the previously mentioned ratios could have been derived. These results highlighted the importance of considering anthropometric characteristics of youth breaststroke swimmers for talent identification and/or athlete monitoring purposes. In addition, these findings may assist orienting swimmers to the appropriate stroke based on their anthropometric characteristics. KW - allometric model KW - maturity KW - limb lengths KW - girths and breadths Y1 - 2018 U6 - https://doi.org/10.1123/pes.2017-0220 SN - 0899-8493 SN - 1543-2920 VL - 30 IS - 3 SP - 393 EP - 401 PB - Human Kinetics Publ. CY - Champaign ER - TY - JOUR A1 - Böckmann, Christine A1 - Brückner, Axel T1 - 100 years of the Runge-Kutta method : a brief editing for schools BT - Hundred years of the Runge-Kutta method : a brief editing for schools N2 - This paper reports on the historical development of the Runge-Kutta methods beginning with the simple Euler method up to an embedded 13-stage method. Moreover, the design and the use of those methods under error order, stability and computation time conditions is edited for students of numerical analysis at undergraduate level. The second part presents applications in natural sciences, compares different methods and illustrates some of the difficulties of numerical solutions. Y1 - 2001 SN - 0268-3679 ER - TY - JOUR A1 - Eichler, Hans Joachim A1 - Haase, Alfred A1 - Menzel, Ralf T1 - 100 watt average output power 1.2*diffraction limited beam from pulsed neodym single rod amplifier with SBS- phaseconjugation BT - Onehundred watt average output 1.2*diffraction limited beam from pulsed neodym single rod amplifier with SBS- phaseconjugation T2 - Hundred watt average output power 1.2*diffraction limited beam from pulsed neodym single rod amplfier with SBS- phaseconjugation Y1 - 1995 ER - TY - JOUR A1 - Tofelde, Stefanie A1 - Schildgen, Taylor F. A1 - Savi, Sara A1 - Pingel, Heiko A1 - Wickert, Andrew D. A1 - Bookhagen, Bodo A1 - Wittmann, Hella A1 - Alonso, Ricardo N. A1 - Cottle, John A1 - Strecker, Manfred T1 - 100 kyr fluvial cut-and-fill terrace cycles since the Middle Pleistocene in the southern Central Andes, NW Argentina JF - Earth & planetary science letters N2 - Fluvial fill terraces in intermontane basins are valuable geomorphic archives that can record tectonically and/or climatically driven changes of the Earth-surface process system. However, often the preservation of fill terrace sequences is incomplete and/or they may form far away from their source areas, complicating the identification of causal links between forcing mechanisms and landscape response, especially over multi-millennial timescales. The intermontane Toro Basin in the southern Central Andes exhibits at least five generations of fluvial terraces that have been sculpted into several-hundred-meter-thick Quaternary valley-fill conglomerates. New surface-exposure dating using nine cosmogenic Be-10 depth profiles reveals the successive abandonment of these terraces with a 100 kyr cyclicity between 75 +/- 7 and 487 +/- 34 ka. Depositional ages of the conglomerates, determined by four Al-26/Be-10 burial samples and U-Pb zircon ages of three intercalated volcanic ash beds, range from 18 +/- 141 to 936 +/- 170 ka, indicating that there were multiple cut-and-fill episodes. Although the initial onset of aggradation at similar to 1 Ma and the overall net incision since ca. 500 ka can be linked to tectonic processes at the narrow basin outlet, the superimposed 100 kyr cycles of aggradation and incision are best explained by eccentricity-driven climate change. Within these cycles, the onset of river incision can be correlated with global cold periods and enhanced humid phases recorded in paleoclimate archives on the adjacent Bolivian Altiplano, whereas deposition occurred mainly during more arid phases on the Altiplano and global interglacial periods. We suggest that enhanced runoff during global cold phases - due to increased regional precipitation rates, reduced evapotranspiration, or both - resulted in an increased sediment-transport capacity in the Toro Basin, which outweighed any possible increases in upstream sediment supply and thus triggered incision. Compared with two nearby basins that record precessional (21-kyr) and long-eccentricity (400-kyr) forcing within sedimentary and geomorphic archives, the recorded cyclicity scales with the square of the drainage basin length. (C) 2017 Elsevier B.V. All rights reserved. KW - Be-10 depth-profiles KW - surface inflation KW - aggradation-incision cycles KW - glacial-interglacial cycles KW - landscape response to climate change KW - Eastern Cordillera Y1 - 2017 U6 - https://doi.org/10.1016/j.epsl.2017.06.001 SN - 0012-821X SN - 1385-013X VL - 473 SP - 141 EP - 153 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Pihlaja, Kalevi A1 - Sinkkonen, Jari A1 - Stájer, Gezá A1 - Koch, Andreas T1 - 1-Oxo-1,3-dithiolanesùsynthesis and stereochemistry N2 - 1-Oxo-1,3-dithiolane (4) and its cis- andtrans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO4 in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with 1H and 13C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=Oax envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=Oax (30 and 27%) as well as S=Oeq (21 and 22%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of 1H-1H coupling constants and 1H and 13C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data. Y1 - 2011 SN - 0749-1581 ER - TY - JOUR A1 - Pihlaja, Kalevi A1 - Sinkkonen, Jari A1 - Stajer, Geza A1 - Koch, Andreas A1 - Kleinpeter, Erich T1 - 1-Oxo-1,3-dithiolanes - synthesis and stereochemistry JF - Magnetic resonance in chemistry N2 - 1-Oxo-1,3-dithiolane (4) and its cis- and trans-2-methyl (5,6), -4-methyl (7,8) and -5-methyl (9,10) derivatives were prepared by oxidizing the corresponding 1,3-dithiolanes (1-3) with NaIO(4) in water. The oxides were purified and their isomers separated using thin layer chromatography. The structural characterization was carried out with (1)H and (13)C NMR spectroscopy and molecular modelling. The sulfoxides 4-6 and 8-10 attain two S(1) type envelopes (sometimes slightly distorted) the S=O(ax) envelope greatly dominating. Cis-4-methyl-1-oxo-1,3-dithiolane is a special case exhibiting both two closely related S=O(ax) (30 and 27%) as well as S=O(eq) (21 and 22%) forms [S(1) and C(4) envelopes, respectively]. The relative energies of these conformations, the values of (1)H-(1)H coupling constants and (1)H and (13)C chemical shifts were estimated by computational methods and they support well the conclusions based on the experimental data. KW - NMR KW - (1)H NMR KW - (13)C NMR KW - sulfur heterocycles KW - conformational analysis KW - computational chemistry Y1 - 2011 U6 - https://doi.org/10.1002/mrc.2764 SN - 0749-1581 VL - 49 IS - 7 SP - 443 EP - 449 PB - Wiley-Blackwell CY - Malden ER - TY - JOUR A1 - Shainyan, Bagrat A. A1 - Suslova, Elena N. A1 - Tran Dinh Phien, A1 - Shlykov, Sergey A. A1 - Heydenreich, Matthias A1 - Kleinpeter, Erich T1 - 1-Methylthio-1-phenyl-1-silacyclohexane: Synthesis, conformational preferences in gas and solution by GED, NMR and theoretical calculations JF - Tetrahedron N2 - 1-Methylthio-1-phenyl-1-silacyclohexane 1, the first silacyclohexane with the sulfur atom at silicon, was synthesized and its molecular structure and conformational preferences studied by gas-phase electron diffraction (GED) and low temperature C-13 and Si-29 NMR spectroscopy (LT NMR). Quantum-chemical calculations were carried out both for the isolated species and solvate complexes in gas and in polar medium. The predominance of the 1-MeSaxPheq conformer in gas phase (1-Ph-eq :1-Ph-ax = 55:45, Delta G degrees = 0.13 kcal/mol) determined from GED is consistent with that measured in the freon solution by LT NMR (1-Ph-eq:1-Ph-ax = 65:35, Delta G degrees = 0.12 kcal/mol), the experimentally measured ratios being close to that estimated by quantum chemical calculations at both the DFT and MP2 levels of theory. (C) 2019 Elsevier Ltd. All rights reserved. KW - 1-Methylthio-1-phenyl-1-silacyclohexane KW - Conformational analysis KW - Gas phase electron diffraction KW - Low-temperature C-13 and Si-29 NMR KW - DFT and MP2 calculations Y1 - 2019 U6 - https://doi.org/10.1016/j.tet.2019.130677 SN - 0040-4020 VL - 75 IS - 46 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Wiesner-Reinhold, Melanie A1 - Barknowitz, Gitte A1 - Florian, Simone A1 - Mewis, Inga A1 - Schumacher, Fabian A1 - Schreiner, Monika A1 - Glatt, Hansruedi T1 - 1-Methoxy-3-indolylmethyl DNA adducts in six tissues, and blood protein adducts, in mice under pak choi diet: time course and persistence JF - Archives of toxicology : official journal of EUROTOX N2 - We previously showed that purified 1-methoxy-3-indolylmethyl (1-MIM) glucosinolate, a secondary plant metabolite in Brassica species, is mutagenic in various in vitro systems and forms DNA and protein adducts in mouse models. In the present study, we administered 1-MIM glucosinolate in a natural matrix to mice, by feeding a diet containing pak choi powder and extract. Groups of animals were killed after 1, 2, 4 and 8 days of pak choi diet, directly or, in the case of the 8-day treatment, after 0, 8 and 16 days of recovery with pak choi-free diet. DNA adducts [N-2-(1-MIM)-dG, N-6-(1-MIM)-dA] in six tissues, as well as protein adducts [tau N-(1-MIM)-His] in serum albumin (SA) and hemoglobin (Hb) were determined using UPLC-MS/MS with isotopically labeled internal standards. None of the samples from the 12 control animals under standard diet contained any 1-MIM adducts. All groups receiving pak choi diet showed DNA adducts in all six tissues (exception: lung of mice treated for a single day) as well as SA and Hb adducts. During the feeding period, all adduct levels continuously increased until day 8 (in the jejunum until day 4). During the 14-day recovery period, N-2-(1-MIM)-dG in liver, kidney, lung, jejunum, cecum and colon decreased to 52, 41, 59, 11, 7 and 2%, respectively, of the peak level. The time course of N-6-(1-MIM)-dA was similar. Immunohistochemical analyses indicated that cell turnover is a major mechanism of DNA adduct elimination in the intestine. In the same recovery period, protein adducts decreased more rapidly in SA than in Hb, to 0.7 and 37%, respectively, of the peak level, consistent with the differential turnover of these proteins. In conclusion, the pak choi diet lead to the formation of high levels of adducts in mice. Cell and protein turnover was a major mechanism of adduct elimination, at least in gut and blood. KW - 1-Methoxy-3-indolylmethyl glucosinolate KW - Neoglucobrassicin KW - DNA adducts KW - Blood protein adducts KW - Pak choi Y1 - 2019 U6 - https://doi.org/10.1007/s00204-019-02452-3 SN - 0340-5761 SN - 1432-0738 VL - 93 IS - 6 SP - 1515 EP - 1527 PB - Springer CY - Heidelberg ER - TY - JOUR A1 - Engelhardt, Ulrike A1 - Linker, Torsten T1 - 1,4-cyclohexadienes as mechanistic probes for the Jacobsen epoxidation : evidence for radical pathways N2 - 1,4-Cyclohexadienes allow a direct comparison of epoxidation and C - H oxidation within the same molecule and give evidence for radical pathways during the Jacobsen epoxidation Y1 - 2005 ER - TY - JOUR A1 - Shainyan, Bagrat A. A1 - Kirpichenko, Svetlana V. A1 - Kleinpeter, Erich A1 - Shlykov, Sergey A. A1 - Osadchiy, Dmitriy Yu A1 - Chipanina, Nina N. A1 - Oznobikhina, Larisa P. T1 - 1,3-Dimethy1-3-silapiperidine - synthesis, molecular structure, and conformational analysis by gas-phase electron diffraction, low temperature NMR, IR and Raman Spectroscopy, and quantum chemical calculations JF - The journal of organic chemistry N2 - The first Si-H-containing azasilaheterocycle, 1,3-dimethyl-3-silapiperidine 1, was synthesized, and its molecular structure and conformational properties were studied by gas-phase electron diffraction (GED), low temperature NMR, IR and Raman spectroscopy and quantum chemical calculations. The compound exists as a mixture of two conformers possessing the chair conformation with the equatorial NMe group and differing by axial or equatorial position of the SiMe group. In the gas phase, the SiMeax conformer predominates (GED: ax/eq = 65(7):35(7)%,Delta G = 0.36(18) kcal/mol; IR: ax/eq = 62(5):38(5)%,Delta G = 0.16(7) kcal/mol). In solution, at 143 k the SiMeeq conformer predominates' in the frozen equilibrium (NMR: ax/eq = 31.5(1.5):68.5(1.5)%, Delta G = -0.22(2) kcal/mol). Thermodynamic parameters of the ring inversion are determined (Delta G(double dagger) = 8.9-9.0 kcal/mol, Delta H-double dagger = 9.6 kcal/mol, Delta S-double dagger = 2.1 eu). High-level quantum chemical calculations :(MP2, G2, CCSD(T)) nicely reproduce the experimental geometry and the predominance of the axial conformer in the gas phase. Y1 - 2013 U6 - https://doi.org/10.1021/jo400289g SN - 0022-3263 VL - 78 IS - 8 SP - 3939 EP - 3947 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Mikat, Jürgen E. R. A1 - Franco, Olga A1 - Regenstein, Wolfgang A1 - Reck, Günter A1 - Knochenhauer, Gerald A1 - Schulz, Burkhard A1 - Orgzall, Ingo T1 - 1,3,4-oxadiazole crystals under high pressure-phase transitions and properties Y1 - 2000 ER - TY - JOUR A1 - Zebger-Gong, Hong A1 - Mueller, Dominik A1 - Diercke, Michaela A1 - Haffner, Dieter A1 - Hocher, Berthold A1 - Verberckmoes, Steven A1 - Schmidt, Sven A1 - D'Haese, Patrick C. A1 - Querfeld, Uwe T1 - 1,25-Dihydroxyvitamin D-3-induced aortic calcifications in experimental uremia: up-regulation of osteoblast markers, calcium-transporting proteins and osterix JF - Journal of hypertension N2 - Background and objective Whether treatment with vitamin D receptor activators contributes to cardiovascular disease in patients with chronic kidney disease is a matter of debate. We studied mechanisms involved in vitamin D-related vascular calcifications in vivo and in vitro. Methods Aortic calcifications were induced in subtotally nephrectomized (SNX) rats by treatment with a high dose (0.25 mu g/kg per day) of 1,25-dihydroxyvitamin D-3 (calcitriol) given for 6 weeks. Likewise, primary rat vascular smooth muscle cells (VSMCs) were incubated with calcitriol at concentrations ranging from 10(-11) to 10(-7) mol/l. Immunohistochemistry revealed that the aortic expression of osteopontin, osteocalcin and bone sialoprotein was significantly increased in calcitriol-treated SNX rats compared to untreated SNX controls. In addition, aortic expression of the transient receptor potential vanilloid calcium channel 6 (TRPV6) and calbindin D9k was significantly up-regulated by treatment with calcitriol. Furthermore, calcitriol significantly increased expression of the osteogenic transcription factor osterix. In-vitro studies showed similar results, confirming that these effects could be attributed to treatment with calcitriol. Conclusions High-dose calcitriol treatment induces an osteoblastic phenotype in VSMC both in SNX rats and in vitro, associated with up-regulation of proteins regulating mineralization and calcium transport, and of the osteogenic transcription factor osterix. KW - calbindin D9k KW - calcitriol KW - calcium transport KW - osteoblast KW - osterix KW - TRPV5 KW - TRPV6 KW - vascular calcification Y1 - 2011 U6 - https://doi.org/10.1097/HJH.0b013e328340aa30 SN - 0263-6352 VL - 29 IS - 2 SP - 339 EP - 348 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Schwarze, Thomas A1 - Sprenger, Tobias A1 - Riemer, Janine T1 - 1,2,3-Triazol-1,4-diyl-Fluoroionophores for Zn2+, Mg2+ and Ca2+ based on Fluorescence Intensity Enhancements in Water JF - ChemistrySelect N2 - Herein, we represent cation-responsive fluorescent probes for the divalent cations Zn2+, Mg2+ and Ca2+, which show cation-induced fluorescence enhancements (FE) in water. The Zn2+-responsive probes Zn1, Zn2, Zn3 and Zn4 are based on o-aminoanisole-N,N-diacetic acid (AADA) derivatives and show in the presence of Zn2+ FE factors of 11.4, 13.9, 6.1 and 8.2, respectively. Most of all, Zn1 and Zn2 show higher Zn2+ induced FE than the regioisomeric triazole linked fluorescent probes Zn3 and Zn4, respectively. In this set, ZN2 is the most suitable probe to detect extracellular Zn2+ levels. For the Mg2+-responsive fluorescent probes Mg1, Mg2 and Mg3 based on o-aminophenol-N,N,O-triacetic acid (APTRA) derivatives, we also found that the regioisomeric linkage influences the fluorescence responds towards Mg2+ (Mg1+100 mM Mg2+ (FEF=13.2) and Mg3+100 mM Mg2+ (FEF=2.1)). Mg2 shows the highest Mg2+-induced FE by a factor of 25.7 and an appropriate K-d value of 3 mM to measure intracellular Mg2+ levels. Further, the Ca2+-responsive fluorescent probes Ca1 and Ca2 equipped with a 1,2-bis(o-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid (BAPTA) derivative show high Ca2+-induced FEs (Ca1 (FEF=22.1) and Ca2 (FEF=23.0)). Herein, only Ca1 (K-d=313 nM) is a suitable Ca2+ fluorescent indicator to determine intracellular Ca2+ levels. KW - calcium KW - fluorescence KW - magnesium KW - probes KW - zinc Y1 - 2020 U6 - https://doi.org/10.1002/slct.202003695 SN - 2365-6549 VL - 5 IS - 41 SP - 12727 EP - 12735 PB - Wiley-VCH CY - Weinheim ER - TY - JOUR A1 - Kammer, Stefan A1 - Starke, Ines A1 - Pietrucha, Andreas A1 - Kelling, Alexandra A1 - Mickler, Wulfhard A1 - Schilde, Uwe A1 - Dosche, Carsten A1 - Kleinpeter, Erich A1 - Holdt, Hans-Jürgen T1 - 1,12-Diazaperylene and 2,11-dialkylated-1,12-diazaperylene iridium(III) complexes [Ir((CN)-N-boolean AND)(2)((NN)-N-boolean AND)]PF6: new supramolecular assemblies JF - Dalton transactions : a journal of inorganic chemistry, including bioinorganic, organometallic, and solid-state chemistry N2 - A series of new monocationic iridium(III) complexes [Ir((CN)-N-boolean AND)(2)((NN)-N-boolean AND)]PF6 with "large-surface" alpha,alpha'-diimin ligands (NN)-N-boolean AND (dap = 1,12-diazaperylene, dmedap = 2,11-dimethyl-1,12-diazaperylene, dipdap = 2,11-diisopropyl-1,12-diazaperylene) and different cyclometalating ligands (CN)-N-boolean AND (piq = 1-phenylisoquinoline, bzq = benzo[h]quinoline, ppz = 1-phenylpyrazole, thpy = 2-(2-thienyl)pyridine, ppy = 2-phenylpyridine, meppy = 2-(4-methylphenyl)pyridine, dfppy = 2-(2,4-difluorophenyl)pyridine) were synthesized. The solid structures of the complexes [Ir(piq)(2)(dap)]PF6, [Ir(bzq)(2)(dap)]PF6, [Ir(ppy)(2)(dipdap)]PF6, [Ir(piq)(2)(dmedap)]PF6, [Ir(ppy)(2)(dap)]PF6 and [Ir(ppz)(2)(dap)]PF6 are reported. In [Ir(piq)(2)(dap)]PF6, the dap ligand and one of the piq ligands of each cationic complex are involved in pi-pi stacking interactions forming supramolecular channels running along the crystallographic c axis. In the crystalline [Ir(bzq)(2)(dap)]PF6 pi-pi stacking interactions between the metal complexes lead to the formation of a 2D layer structure. In addition, CH-pi interactions were found in all compounds, which are what stabilizes the solid structure. In particular, a significant number of them were found in [Ir(piq)(2)(dap)]PF6 and [Ir(bzq)(2)(dap)]PF6. The crystal structures of [Ir(ppy)(2)(dipdap)]PF6 and [Ir(ppy)(2)(dmedap)]PF6 are also presented, being the first examples of bis-cyclometalated iridium(III) complexes with phenanthroline-type alpha,alpha'-diimin ligands bearing bulky alkyl groups in the neighbourhood of the N-donor atoms. These ligands implicate a distorted octahedral coordination geometry that in turn destabilized the Ir-N-N boolean AND N bonds. The new iridium (III) complexes are not luminescent. All compounds show an electrochemically irreversible anodic peak between 1.15 and 1.58 V, which is influenced by the different cyclometalated ligands. All of the new complexes show two reversible successive one-electron "large-surface" ligand-centred reductions around -0.70 V and -1.30 V. Electrospray ionisation mass spectrometry (ESI-MS) and collision induced decomposition (CID) measurements were used to investigate the stability of the new complexes. Thereby, the stability agreed well with the order of the Ir-N-N boolean AND N bond lengths. Y1 - 2012 U6 - https://doi.org/10.1039/c2dt30412k SN - 1477-9226 VL - 41 IS - 34 SP - 10219 EP - 10227 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Awad, Duha Jawad A1 - Conrad, Franziska A1 - Koch, Andreas A1 - Schilde, Uwe A1 - Poeppl, Andreas A1 - Strauch, Peter T1 - 1,10-phenanthroline-dithiolate mixed ligand transition metal complexes : synthesis, characterization and EPR spectroscopy N2 - A series of new N2S2 mixed ligand transition metal complexes, where N-2 is phenanthroline and S-2 is 1,2- dithiooxalate (dto) or 1,2-dithiosquarate (dtsq), has been synthesized and characterized. IR spectra reveal that the 1,2- dithiolate ligands are coordinated via the sulfur atoms forming a N2S2 coordination sphere. The copper(II) complex [Cu(phen)(dto)] was studied by EPR spectroscopy as a diamagnetically diluted powder. The diamagnetic dilution resulted from doping of the copper complex into the isostructural host lattice of the nickel complex [Ni(phen)(dto)]. The electronic situation in the frontier orbitals of the copper complex calculated from the experimental data is compared to the results of EHT and DFT calculations. Furthermore, one side product, chlorobis(1,10-phenanthroline)copper(I) ethanol solvate hydrate [(phen)(2)CuCl]center dot C2H5OH center dot H2O, was formed by a reduction process and characterized by X-ray diffraction. In the crystal packing one-dimensional columns of dimers are formed, stabilized by significant pi-pi interactions. Y1 - 2010 UR - http://www.sciencedirect.com/science/journal/00201693 U6 - https://doi.org/10.1016/j.ica.2010.01.021 SN - 0020-1693 ER - TY - JOUR A1 - Shaki, Samuel A1 - Sery, Noa A1 - Fischer, Martin H. T1 - 1 + 2 is more than 2 + 1: Violations of commutativity and identity axioms in mental arithmetic JF - Journal of cognitive psychology N2 - Over the past decade or so, a large number of studies have revealed that conceptual meaning is sensitive to situational context. More recently, similar contextual influences have been documented in the domain of number knowledge. Here we show such context dependency in a length production task. Adult participants saw single digit addition problems of the form n1 + n2 and produced the sum by changing bi-directionally the length of a horizontally extended line, using radially arranged buttons. We found that longer lines were produced when n1 < n2 compared to n1 > n2 and that unit size increased with result size. Thus, the mathematical axioms of commutativity and identity do not seem to hold in mental addition. We discuss implications of these observations for our understanding of cognitive mechanisms involved in mental arithmetic and for situated cognition generally. KW - Operand order effect KW - Situated cognition KW - Mental number line KW - SNARC KW - Operational momentum Y1 - 2015 U6 - https://doi.org/10.1080/20445911.2014.973414 SN - 2044-5911 SN - 2044-592X VL - 27 IS - 4 SP - 471 EP - 477 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - Bois, Juliana A1 - Körzdörfer, Thomas T1 - 0 How Bond Length Alternation and Thermal Disorder Affect the Optical Excitation Energies of pi-Conjugated Chains: A Combined Density Functional Theory and Molecular Dynamics Study JF - Journal of chemical theory and computation N2 - We dissect the sources of error leading to inaccuracies in the description of the geometry and optical excitation energies of pi-conjugated polymers. While the ground-state bond length alternation is shown to be badly reproduced by standard functionals, the recently adapted functionals PBEh* and omega PBE* as well as the double hybrid functional XYGJ-OS manage to replicate results obtained at the CCSD(T) level. By analysis of the bond length alternation in the excited state, a sensitive dependence of the exciton localization on the long-range behavior of the functional and the amount of Hartree-Fock exchange present is shown. Introducing thermal disorder through molecular dynamics simulations allows the consideration of a range of thermally accessible configurations of each oligomer, including trans to cis rotations, which break the conjugation of the backbone. Thermal disorder has a considerable effect when combined with functionals that overestimate the delocalization of the excitation, such as B3LYP. For functionals with a larger amount of exact exchange such as our PBEh* and omega PBE*, however, the effect is small, as excitations are often localized enough to fit between twists in the chain. Y1 - 2016 U6 - https://doi.org/10.1021/acs.jctc.5b01070 SN - 1549-9618 SN - 1549-9626 VL - 12 SP - 1872 EP - 1882 PB - American Chemical Society CY - Washington ER - TY - JOUR A1 - Sentance, Sue A1 - Hodges, Steve T1 - .NET Gadgeteer Workshop JF - Commentarii informaticae didacticae : (CID) Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus-64654 SN - 1868-0844 SN - 2191-1940 IS - 6 SP - 159 PB - Universitätsverlag Potsdam CY - Potsdam ER - TY - JOUR A1 - Blaszczak, Joanna T1 - -kolwiek pronouns in polish : negative polarity items of free choice items or both? Y1 - 1999 SN - 3-87690-738-1 ER - TY - JOUR A1 - Carlà-Uhink, Filippo T1 - (Re-)Founding Italy: The Social War, Its Aftermath and the Construction of a Roman-Italic Identity in the Roman Republic JF - History in Flux: Journal of the Department of History, Faculty of Humanities, Juraj Dobrila University of Pula N2 - The Social War (91-88 BCE) is one of the most significant episodes in Roman history: from this war, in which Rome fought against her Italic allies, emerged the elite that would lead the Republic in the last decades of its existence and that would provide the senatorial aristocracy of the early imperial age. The Italic rebels were defeated militarily, yet they achieved their political aims. As such, this war – and its elaboration and memorialization in Roman cultural memory – provides a very interesting case study about how "victory" and "defeat" are constructed discursively after a disruptive war, and how its narration is "functionalized" for a re-foundation of the civic body. KW - ancient Italy KW - ancient Rome KW - social war KW - senatorial aristocracy KW - cultural memory Y1 - 2019 UR - https://hrcak.srce.hr/230778 U6 - https://doi.org/10.32728/flux.2019.1.1 VL - 1 IS - 1 SP - 3 EP - 19 ER - TY - JOUR A1 - Zimmermann, Malte A1 - De Veaugh-Geiss, Joseph P. A1 - Tönnis, Swantje A1 - Onea, Edgar T1 - (Non-)exhaustivity in focus partitioning across languages JF - Approaches to Hungarian N2 - We present novel experimental evidence on the availability and the status of exhaustivity inferences with focus partitioning in German, English, and Hungarian. Results suggest that German and English focus-background clefts and Hungarian focus share important properties, (É. Kiss 1998, 1999; Szabolcsi 1994; Percus 1997; Onea & Beaver 2009). Those constructions are anaphoric devices triggering an existence presupposition. EXH-inferences are not obligatory in such constructions in English, German, or Hungarian, against some previous literature (Percus 1997; Büring & Križ 2013; É. Kiss 1998), but in line with pragmatic analyses of EXH-inferences in clefts (Horn 1981, 2016; Pollard & Yasavul 2016). The cross-linguistic differences in the distribution of EXH-inferences are attributed to properties of the Hungarian number marking system. KW - clefts KW - definite pseudoclefts KW - Hungarian focus KW - exhaustivity KW - experimental evidence KW - semantics-pragmatics interface Y1 - 2020 VL - 16 PB - John Benjamins CY - Amsterdam ER - TY - JOUR A1 - Jürgensen, Helmut A1 - Konstantinidis, Stavros T1 - (Near-)inverses of sequences N2 - We introduce the notion of a near-inverse of a non-decreasing sequence of positive integers; near-inverses are intended to assume the role of inverses in cases when the latter cannot exist. We prove that the near-inverse of such a sequence is unique; moreover, the relation of being near-inverses of each other is symmetric, i.e. if sequence g is the near-inverse of sequence f, then f is the near-inverse of g. There is a connection, by approximations, between near- inverses of sequences and inverses of continuous strictly increasing real-valued functions which can be exploited to derive simple expressions for near-inverses Y1 - 2006 UR - http://www.informaworld.com/openurl?genre=journal&issn=0020-7160 U6 - https://doi.org/10.1080/00207160500537801 SN - 0020-7160 ER - TY - JOUR A1 - Pade, Sylvia A1 - Schmidt, Hartmut A1 - Stumpe, Joachim A1 - Fischer, Thomas M. T1 - (Micro-)fluorescence spectroscopy of side chain polymers with bezanilide moieties Y1 - 1996 ER - TY - JOUR A1 - Titov, Evgenii A1 - Kopp, Tristan A1 - Hoche, Joscha A1 - Humeniuk, Alexander A1 - Mitrić, Roland T1 - (De)localization dynamics of molecular excitons BT - comparison of mixed quantum-classical and fully quantum treatments JF - Physical chemistry, chemical physics : PCCP ; a journal of European chemical societies N2 - Molecular excitons play a central role in processes of solar energy conversion, both natural and artificial. It is therefore no wonder that numerous experimental and theoretical investigations in the last decade, employing state-of-the-art spectroscopic techniques and computational methods, have been driven by the common aim to unravel exciton dynamics in multichromophoric systems. Theoretically, exciton (de)localization and transfer dynamics are most often modelled using either mixed quantum-classical approaches (e.g., trajectory surface hopping) or fully quantum mechanical treatments (either using model diabatic Hamiltonians or direct dynamics). Yet, the terms such as "exciton localization" or "exciton transfer" may bear different meanings in different works depending on the method in use (quantum-classical vs. fully quantum). Here, we relate different views on exciton (de)localization. For this purpose, we perform molecular surface hopping simulations on several tetracene dimers differing by a magnitude of exciton coupling and carry out quantum dynamical as well as surface hopping calculations on a relevant model system. The molecular surface hopping simulations are done using efficient long-range corrected time-dependent density functional tight binding electronic structure method, allowing us to gain insight into different regimes of exciton dynamics in the studied systems. Y1 - 2022 U6 - https://doi.org/10.1039/d2cp00586g SN - 1463-9076 SN - 1463-9084 VL - 24 IS - 20 SP - 12136 EP - 12148 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Henkel, Carsten A1 - Gardiner, Simon A. A1 - Negretti, Antonio T1 - (De)coherence physics with condensates in microtraps N2 - We discuss the dynamics of a condensate in a miniaturized electromagnetic trap formed above a microstructured substrate. Recent experiments have found that trap lifetimes get reduced when approaching the substrate because atoms couple to thermally excited near fields. The data agree quantitatively with our theory [Appl. Phys. B 69, 379 (1999)]. We focus on the decoherence of a quantum degenerate gas in a quasi-one-dimensional trap. Monte Carlo simulations indicate that atom interactions reduce the condensate decoherence rate. This is explained by a simple theory in terms of the suppression of long-wavelength excitations. We present preliminary simulation results for the adiabatic generation of dark solitons Y1 - 2004 SN - 1054-660X ER - TY - JOUR A1 - Pezzini, Giuseppe ED - Ambühl, Annemarie ED - Carlà-Uhink, Filippo ED - Rollinger, Christian ED - Walde, Christine T1 - (Classical) Narratives of Decline in Tolkien: Renewal, Accommodation, Focalisation JF - thersites 15 N2 - The paper investigates Tolkien’s narratives of decline through the lens of their classical ancestry. Narratives of decline are widespread in ancient culture, in both philosophical and literary discourses. They normally posit a gradual degradation (moral and ontological) from an idealized Golden Age, which went hand-in-hand with increasing detachment of gods from mortal affairs. Narratives of decline are also at the core of Tolkien’s mythology, constituting yet another underresearched aspect of classical influence on Tolkien. Such Classical narratives reverberate e.g. in Tolkien’s division of Arda’s history into ages, from an idealized First Age filled with Joy and Light to a Third Age, described as “Twilight Age (…) the first of the broken and changed world” (Letters 131). More generally, these narratives are related to Tolkien’s notorious perception of history as a “long defeat” (Letters 195) and to that “heart-racking sense of the vanished past” which pervades Tolkien’s works – the emotion which, in his words, moved him “supremely” and which he found “small difficulty in evoking” (Letters 91). The paper analyses the reception of narratives of decline in Tolkien’s legendarium, pointing out similarities but also contrasts and differences, with the aim to discuss some key patterns of (classical) reception in Tolkien’s theory and practice (‘renewal’, ‘accommodation’, ‘focalization’). KW - narrative of decline KW - Hesiod KW - reception KW - focalization KW - accommodation Y1 - 2022 U6 - https://doi.org/10.34679/thersites.vol15.213 SN - 2364-7612 VL - 2022 IS - 15 SP - 25 EP - 51 ER - TY - JOUR A1 - Kleinpeter, Erich A1 - Koch, Andreas T1 - (Anti)aromaticity of dehydroannulenes of various ring size proved by the ring current effect in H-1 NMR spectra JF - Tetrahedron N2 - The spatial magnetic properties (Through-Space NMR Shieldings-TSNMRS) of already synthesized dehydro[n]annulenes of various ring size (from C-12 to C-20) have been computed, visualized as Isochemical Shielding Surfaces (ICSS) of various size and direction, and were examined subject to present (anti)aromaticity. For this purpose the thus quantified ring current effect of the macro cycles on proximate protons in proton NMR spectra was employed. KW - Dehydro[n]annulenes KW - (Anti)aromaticity KW - TSNMRS KW - H-1 NMR spectroscopy KW - Anisotropic effect KW - Theoretical calculations KW - ICSS Y1 - 2013 U6 - https://doi.org/10.1016/j.tet.2012.12.019 SN - 0040-4020 VL - 69 IS - 5 SP - 1481 EP - 1488 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Paz, Cristian A1 - Becerra, Jose A1 - Silva, Mario A1 - Burgos, Viviana A1 - Heydenreich, Matthias A1 - Schmidt, Bernd A1 - Thu Tran, A1 - Vetter, Irina T1 - (-)-Pentylsedinine, a New Alkaloid from the Leaves of Lobelia tupa with Agonist Activity at Nicotinic Acetylcholine Receptor JF - Natural product communications : an international journal for communications and reviews N2 - Lobelia tupa, also called devil's tobacco, is a native plant from the center-south of Chile which has been used by the native people of Chile as a hallucinogenic and anesthetic plant. A new piperidine alkaloid, called pentylsedinine, which comprises five carbons in the side chain, was isolated from the aerial part of L. tupa, along with lobeline and lobelanidine. The structure was established on the basis of 1D and 2D NMR spectroscopy. While lobeline is a neutral antagonist at alpha 3 beta 2/alpha 3 beta 4 nAChR and alpha 7 nAChR, both lobelanidine and pentylsedinine act as partial agonists at nAChR KW - Lobelia tupa KW - Piperidine alkaloid KW - nAChR KW - Pentylsedinine Y1 - 2015 SN - 1934-578X SN - 1555-9475 VL - 10 IS - 8 SP - 1355 EP - 1357 PB - NPC CY - Westerville ER -