@article{SchorckChristliebCohenetal.2009, author = {Schorck, Torben and Christlieb, Norbert and Cohen, Judy G. and Beers, Timothy C. and Shectman, Steve and Thompson, Ian and McWilliam, Andrew and Bessell, Michael S. and Norris, John E. and Mel{\´e}ndez, Jorge and Ram{\"i}rez, Solange and Haynes, D. and Cass, Paul and Hartley, Malcolm and Russell, Ken and Watson, Fred and Zickgraf, Franz-Josef and Behnke, Berit and Fechner, Cora and Fuhrmeister, Birgit and Barklem, Paul S. and Edvardsson, Bengt and Frebel, Anna and Wisotzki, Lutz and Reimers, Dieter}, title = {The stellar content of the Hamburg/ESO survey : V. the metallicity distribution function of the Galactic halo}, issn = {0004-6361}, doi = {10.1051/0004-6361/200810925}, year = {2009}, abstract = {We determine the metallicity distribution function (MDF) of the Galactic halo by means of a sample of 1638 metal-poor stars selected from the Hamburg/ESO objective-prism survey (HES). The sample was corrected for minor biases introduced by the strategy for spectroscopic follow-up observations of the metal-poor candidates, namely "best and brightest stars first". Comparison of the metallicities [Fe/H] of the stars determined from moderate-resolution (i.e., R similar to 2000) follow-up spectra with results derived from abundance analyses based on high-resolution spectra (i.e., R > 20 000) shows that the [Fe/H] estimates used for the determination of the halo MDF are accurate to within 0.3 dex, once highly C-rich stars are eliminated. We determined the selection function of the HES, which must be taken into account for a proper comparison between the HES MDF with MDFs of other stellar populations or those predicted by models of Galactic chemical evolution. The latter show a reasonable agreement with the overall shape of the HES MDF for [Fe/H] > -3.6, but only a model of Salvadori et al. (2007) with a critical metallicity for low-mass star formation of Z(cr) = 10(-3.4) Z(circle dot) reproduces the sharp drop at [Fe/H] similar to -3.6 present in the HES MDF. Although currently about ten stars at [Fe/H] < -3.6 are known, the evidence for the existence of a tail of the halo MDF extending to [Fe/H] similar to -5.5 is weak from the sample considered in this paper, because it only includes two stars [Fe/H] < -3.6. Therefore, a comparison with theoretical models has to await larger statistically complete and unbiased samples. A comparison of the MDF of Galactic globular clusters and of dSph satellites to the Galaxy shows qualitative agreement with the halo MDF, derived from the HES, once the selection function of the latter is included. However, statistical tests show that the differences between these are still highly significant.}, language = {en} } @article{GarciaSteinigerReichetal.2006, author = {Garcia, A. L. and Steiniger, J. and Reich, S. C. and Weickert, M. O. and Harsch, I. and Machowetz, A. and Mohlig, M. and Spranger, Joachim and Rudovich, N. N. and Meuser, F. and Doerfer, J. and Katz, N. and Speth, M. and Zunft, Hans-Joachim Franz and Pfeiffer, Andreas F. H. and Koebnick, Corinna}, title = {Arabinoxylan fibre consumption improved glucose metabolism, but did not affect serum adipokines in subjects with impaired glucose tolerance}, series = {Hormone and metabolic research}, volume = {38}, journal = {Hormone and metabolic research}, number = {2}, publisher = {Thieme}, address = {Stuttgart}, issn = {0018-5043}, doi = {10.1055/s-2006-955089}, pages = {761 -- 766}, year = {2006}, abstract = {The consumption of arabinoxylan, a soluble fibre fraction, has been shown to improve glycemic control in type 2 diabetic subjects. Soluble dietary fibre may modulate gastrointestinal or adipose tissue hormones regulating food intake. The present study investigated the effects of arabinoxylan consumption on serum glucose, insulin, lipids, leptin, adiponectin and resistin in subjects with impaired glucose tolerance. In a randomized, single-blind, controlled, crossover intervention trial, 11 adults consumed white bread rolls as either placebo or supplemented with 15g arabinoxylan for 6 weeks with a 6-week washout period. Fasting serum glucose, insulin, triglycerides, unesterified fatty acids, apolipoprotein A1 and B, adiponectin, resistin and leptin were assessed before and after intervention. Fasting serum glucose, serum triglycerides and apolipoprotein A-1 were significantly lower during arabinoxylan consumption compared to placebo (p = 0.029, p = 0.047; p = 0.029, respectively). No effects of arabinoxylan were observed for insulin, adiponectin, leptin and resistin as well as for apolipoprotein B, and unesterified fatty acids. In conclusion, the consumption of AX in subjects with impaired glucose tolerance improved fasting serum glucose, and triglycerides. However, this beneficial effect was not accompanied by changes in fasting adipokine concentrations.}, language = {en} } @article{KoebnickPlankHabibiWirsametal.2004, author = {Koebnick, Corinna and Plank-Habibi, S. and Wirsam, B. and Gruendel, Sindy and Hahn, A. and Meyer-Kleine, C. and Leitzmann, C. and Zunft, Hans-Joachim Franz}, title = {Double-blind, randomized feedback control fails to improve the hypocholesterolemic effect of a plant-based low- fat diet in patients with moderately elevated total cholesterol levels}, year = {2004}, abstract = {Objective: To determine whether the cholesterol-lowering effect of a plant-based low-fat diet can be improved by a flexible control design that controls the extent of fat reduction based on the individual response of blood cholesterol. Design: Randomized, double-blind intervention study. Setting: A hotel in Prerow, Germany. Subjects: A total of 32 participants ( 21 female and 11 male participants) with total cholesterol level >5.7 mmol/l. Intervention: The control group consumed a plant-based low-fat diet with constantly 20\% of energy as fat; the intervention group received a diet with either 20 or 15\% of energy as fat, depending on the serum cholesterol response of the preceding week. A flexible control design based on the individual cholesterol response during a run-in period of 1 week was used within a low-fat intervention. Results: During the run-in period, the consumption of a plant-based low-fat diet led to a reduction in total cholesterol by 18 +/- 6 mmol/l ( P<0.001), in LDL cholesterol by 19 +/- 9 mmol/l ( P<0.001) and triglycerides by 13 +/- 3 mmol/l ( P<0.001). During the feedback control period, an additional reduction in total cholesterol by 13 +/- 8 ( P<0.001) and in LDL cholesterol by 17 +/- 11 (P<0.001) was observed compared to 15715 and 7718 in the control group. The effect of an additional feedback control was only marginal and not statistically significant compared to the effect of the low-fat diet alone. Conclusions: On a level of fat intake already reduced to 20\% of energy, the use of a feedback control to adapt the fat content of the diet depending on the individual serum cholesterol response was not more effective in reducing blood cholesterol levels than a plant-based low-fat diet alone. Sponsorship: Institute of Micro-Ecology, Herborn; the Stoll VITA Foundation, Waldshut; ALBAT+WIRSAM Software, Linden; Reformhaus Technical College, Oberstedten; Kolln Flocken Werke, Elmshorn, all in Germany}, language = {en} } @article{WarschburgerBuschBaueretal.2004, author = {Warschburger, Petra and Busch, S. and Bauer, C. P. and Kiosz, D. and Stachow, R. and Petermann, Franz}, title = {Health-related quality of life in children and adolescents with asthma : results from the ESTAR study}, year = {2004}, abstract = {Our aim was to assess the psychosocial well-being of asthmatic children and adolescents, the influencing factors, and to determine the effect of inpatient rehabilitation on their quality of life; 226 asthmatic children and adolescents participated in the inpatient rehabilitation (IG). The comparison group (CG) included 92 asthmatic children and adolescents receiving standard medical treatments. Patients were aged between 8 and 16 years and were predominantly male. The health-related quality of life was measured with the German version of the "Paediatric Asthma Quality of Life Questionnaire." Interviews were carried out for IG 2 weeks before the commencement of their inpatient stay and 1 year after their stay ended. The same time schedule was carried out for CG. All patients reported a mild to moderate impairment of their quality of life. Girls described a slightly lower quality of life than boys. With increasing asthma severity, quality of life decreased. Inpatients described a lower quality of life than CG at enrollment. Inpatient rehabilitation resulted in a greater improvement of quality of life over time for IG than for CG. Gender and severity status had no effect on this time course. The only modestly affected quality of life may reflect the good adaptation to the disease and medical treatment. Children and adolescents in the IG recorded improvements in their quality of life. Differences in quality of life based on gender and disease severity were not shown to influence the improvements. In summary, inpatient rehabilitation results in an improvement of health-related quality of life. Further research concerning the psychosocial situation of children and adolescents in this setting is needed}, language = {en} } @article{DellingerEsslHojsgaardetal.2016, author = {Dellinger, Agnes S. and Essl, Franz and Hojsgaard, Diego and Kirchheimer, Bernhard and Klatt, Simone and Dawson, Wayne and Pergl, Jan and Pysek, Petr and van Kleunen, Mark and Weber, Ewald and Winter, Marten and Hoerandl, Elvira and Dullinger, Stefan}, title = {Niche dynamics of alien species do not differ among sexual and apomictic flowering plants}, series = {New phytologist : international journal of plant science}, volume = {209}, journal = {New phytologist : international journal of plant science}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {0028-646X}, doi = {10.1111/nph.13694}, pages = {1313 -- 1323}, year = {2016}, abstract = {We compiled global occurrence data sets of 13 congeneric sexual and apomictic species pairs, and used principal components analysis (PCA) and kernel smoothers to compare changes in climatic niche optima, breadths and unfilling/expansion between native and alien ranges. Niche change metrics were compared between sexual and apomictic species. All 26 species showed changes in niche optima and/or breadth and 14 species significantly expanded their climatic niches. However, we found no effect of the reproductive system on niche dynamics. Instead, species with narrower native niches showed higher rates of niche expansion in the alien ranges. Our results suggest that niche shifts are frequent in plant invasions but evolutionary potential may not be of major importance for such shifts. Niche dynamics rather appear to be driven by changes of the realized niche without adaptive change of the fundamental climatic niche.}, language = {en} } @article{RyllSchmitzdeBooretal.2018, author = {Ryll, Britta and Schmitz, Andreas and de Boor, Johannes and Franz, Alexandra and Whitfield, Pamela S. and Reehuis, Manfred and Hoser, Andreas and M{\"u}ller, Eckhard and Habicht, Klaus and Fritscht, Katharina}, title = {Structure, phase composition, and thermoelectric properties of YbxCo4Sb12 and their dependence on synthesis method}, series = {ACS applied energy materials}, volume = {1}, journal = {ACS applied energy materials}, number = {1}, publisher = {American Chemical Society}, address = {Washington}, issn = {2574-0962}, doi = {10.1021/acsaem.7b00015}, pages = {113 -- 122}, year = {2018}, abstract = {We present a combined microscopic and macroscopic study of YbxCo4Sb12 skutterudites for a range of nominal filling fractions, 0.15 < x < 0.75. The samples were synthesized using two different methods — a melt-quench-annealing route in evacuated quartz ampoules and a non-equilibrium ball-mill route — for which we directly compare the crystal structure and phase composition as well as the thermoelectric properties. Rietveld refinements of high-quality neutron powder diffraction data reveal about a 30-40\% smaller Yb occupancy on the crystallographic 2a site than nominally expected for both synthesis routes. We observe a maximum filling fraction of at least 0.439(7) for a sample synthesized by the ball-mill routine, exceeding theoretical predictions of the filling fraction limit of 0.2-0.3. A single secondary phase of CoSb2 is observed in ball-mill-synthesized samples, while two secondary phases, CoSb2 and YbSb2, are detected for samples prepared by the ampoule route. A detrimental influence of the secondary phases on the thermoelectric properties is observed for secondary-phase fractions larger than 8 wt \% regardless of the kind of secondary phase. The largest figure of merit of all samples with a ZT ∼ 1.0 at 723 K is observed for the sample with a refined Yb content of x2a = 0.159(3), synthesized by the ampoule route.}, language = {en} } @article{WernetKunnusJosefssonetal.2015, author = {Wernet, Philippe and Kunnus, Kristjan and Josefsson, Ida and Rajkovic, Ivan and Quevedo, Wilson and Beye, Martin and Schreck, Simon and Gruebel, S. and Scholz, Mirko and Nordlund, Dennis and Zhang, Wenkai and Hartsock, Robert W. and Schlotter, William F. and Turner, Joshua J. and Kennedy, Brian and Hennies, Franz and de Groot, Frank M. F. and Gaffney, Kelly J. and Techert, Simone and Odelius, Michael and F{\"o}hlisch, Alexander}, title = {Orbital-specific mapping of the ligand exchange dynamics of Fe(CO)(5) in solution}, series = {Nature : the international weekly journal of science}, volume = {520}, journal = {Nature : the international weekly journal of science}, number = {7545}, publisher = {Nature Publ. Group}, address = {London}, issn = {0028-0836}, doi = {10.1038/nature14296}, pages = {78 -- 81}, year = {2015}, abstract = {Transition-metal complexes have long attracted interest for fundamental chemical reactivity studies and possible use in solar energy conversion(1,2). Electronic excitation, ligand loss from the metal centre, or a combination of both, creates changes in charge and spin density at the metal site(3-11) that need to be controlled to optimize complexes for photocatalytic hydrogen production(8) and selective carbon-hydrogen bond activation(9-11). An understanding at the molecular level of how transition-metal complexes catalyse reactions, and in particular of the role of the short-lived and reactive intermediate states involved, will be critical for such optimization. However, suitable methods for detailed characterization of electronic excited states have been lacking. Here we show, with the use of X-ray laser-based femtosecond-resolution spectroscopy and advanced quantum chemical theory to probe the reaction dynamics of the benchmark transition-metal complex Fe(CO)(5) in solution, that the photo-induced removal of CO generates the 16-electron Fe(CO)(4) species, a homogeneous catalyst(12,13) with an electron deficiency at the Fe centre(14,15), in a hitherto unreported excited singlet state that either converts to the triplet ground state or combines with a CO or solvent molecule to regenerate a penta-coordinated Fe species on a sub-picosecond timescale. This finding, which resolves the debate about the relative importance of different spin channels in the photochemistry of Fe(CO)(5) (refs 4, 16-20), was made possible by the ability of femtosecond X-ray spectroscopy to probe frontier-orbital interactions with atom specificity. We expect the method to be broadly applicable in the chemical sciences, and to complement approaches that probe structural dynamics in ultrafast processes.}, language = {en} } @article{MartinezGonzalezPastorYabarLaggetal.2016, author = {Martinez Gonzalez, M. J. and Pastor Yabar, A. and Lagg, A. and Asensio Ramos, A. and Collados Vera, M. and Solanki, S. K. and Balthasar, H. and Berkefeld, T. and Denker, Carsten and Doerr, H. P. and Feller, A. and Franz, M. and Gonz{\´a}lez Manrique, Sergio Javier and Hofmann, A. and Kneer, F. and Kuckein, Christoph and Louis, R. and von der L{\"u}he, O. and Nicklas, H. and Orozco, D. and Rezaei, R. and Schlichenmaier, R. and Schmidt, D. and Schmidt, W. and Sigwarth, M. and Sobotka, M. and Soltau, D. and Staude, J. and Strassmeier, Klaus G. and Verma, Meetu and Waldman, T. and Volkmer, R.}, title = {Inference of magnetic fields in the very quiet Sun}, series = {Journal of geophysical research : Earth surface}, volume = {596}, journal = {Journal of geophysical research : Earth surface}, publisher = {EDP Sciences}, address = {Les Ulis}, issn = {1432-0746}, doi = {10.1051/0004-6361/201628449}, pages = {11}, year = {2016}, abstract = {Context. Over the past 20 yr, the quietest areas of the solar surface have revealed a weak but extremely dynamic magnetism occurring at small scales (<500 km), which may provide an important contribution to the dynamics and energetics of the outer layers of the atmosphere. Understanding this magnetism requires the inference of physical quantities from high-sensitivity spectro-polarimetric data with high spatio-temporal resolution. Aims. We present high-precision spectro-polarimetric data with high spatial resolution (0.4") of the very quiet Sun at 1.56 mu m obtained with the GREGOR telescope to shed some light on this complex magnetism. Methods. We used inversion techniques in two main approaches. First, we assumed that the observed profiles can be reproduced with a constant magnetic field atmosphere embedded in a field-free medium. Second, we assumed that the resolution element has a substructure with either two constant magnetic atmospheres or a single magnetic atmosphere with gradients of the physical quantities along the optical depth, both coexisting with a global stray-light component. Results. Half of our observed quiet-Sun region is better explained by magnetic substructure within the resolution element. However, we cannot distinguish whether this substructure comes from gradients of the physical parameters along the line of sight or from horizontal gradients (across the surface). In these pixels, a model with two magnetic components is preferred, and we find two distinct magnetic field populations. The population with the larger filling factor has very weak (similar to 150 G) horizontal fields similar to those obtained in previous works. We demonstrate that the field vector of this population is not constrained by the observations, given the spatial resolution and polarimetric accuracy of our data. The topology of the other component with the smaller filling factor is constrained by the observations for field strengths above 250 G: we infer hG fields with inclinations and azimuth values compatible with an isotropic distribution. The filling factors are typically below 30\%. We also find that the flux of the two polarities is not balanced. From the other half of the observed quiet-Sun area similar to 50\% are two-lobed Stokes V profiles, meaning that 23\% of the field of view can be adequately explained with a single constant magnetic field embedded in a non-magnetic atmosphere. The magnetic field vector and filling factor are reliable inferred in only 50\% based on the regular profiles. Therefore, 12\% of the field of view harbour hG fields with filling factors typically below 30\%. At our present spatial resolution, 70\% of the pixels apparently are non-magnetised.}, language = {en} } @article{HengstlerRingelBiefangetal.2000, author = {Hengstler, Jan Georg and Ringel, M. and Biefang, Katja and Hammel, S. and Milbert, U. and Gerl, M. and Klebach, M. and Diener, B. and Platt, Karl-Ludwig and B{\"o}ttger, Thomas and Steinberg, Pablo and Oesch, Franz}, title = {Cultures with cryopreserved hepatocytes : applicability for studies of enzyme induction}, year = {2000}, language = {en} } @article{PietzschHenniesMiedemaetal.2015, author = {Pietzsch, Annette and Hennies, Franz and Miedema, Piter S. and Kennedy, Brian and Schlappa, Justine and Schmitt, Thorsten and Strocov, Vladimir N. and F{\"o}hlisch, Alexander}, title = {Snapshots of the Fluctuating Hydrogen Bond Network in Liquid Water on the Sub-Femtosecond Timescale with Vibrational Resonant Inelastic x-ray Scattering}, series = {Physical review letters}, volume = {114}, journal = {Physical review letters}, number = {8}, publisher = {American Physical Society}, address = {College Park}, issn = {0031-9007}, doi = {10.1103/PhysRevLett.114.088302}, pages = {5}, year = {2015}, abstract = {Liquid water molecules interact strongly with each other, forming a fluctuating hydrogen bond network and thereby giving rise to the anomalous phase diagram of liquid water. Consequently, symmetric and asymmetric water molecules have been found in the picosecond time average with IR and optical Raman spectroscopy. With subnatural linewidth resonant inelastic x-ray scattering (RIXS) at vibrational resolution, we take sub-femtosecond snapshots of the electronic and structural properties of water molecules in the hydrogen bond network. We derive a strong dominance of nonsymmetric molecules in liquid water in contrast to the gas phase on the sub-femtosecond timescale of RIXS and determine the fraction of highly asymmetrically distorted molecules.}, language = {en} }