TY - JOUR A1 - Pimpalpalle, Tukaram M. A1 - Yin, Jian A1 - Linker, Torsten T1 - Barton radical reactions of 2-C-branched carbohydrates JF - Organic & biomolecular chemistry : an international journal of synthetic, physical and biomolecular organic chemistry N2 - Barton esters have been introduced into the side chain of carbohydrates with high yields in only a few steps from easily available glycals. Their radical reactions afford 2-C-methyl and 2-C-bromomethyl hexoses, pentoses and disaccharides in good yields in analytically pure form. Since the Barton esters have been synthesized by an oxidative radical addition and their transformations by reductive radical processes, our results demonstrate the power of such reactions in carbohydrate chemistry. Y1 - 2012 U6 - https://doi.org/10.1039/c1ob06370g SN - 1477-0520 VL - 10 IS - 1 SP - 103 EP - 109 PB - Royal Society of Chemistry CY - Cambridge ER - TY - JOUR A1 - Wang, Yongbo A1 - Liu, Xingqi A1 - Mischke, Steffen A1 - Herzschuh, Ulrike T1 - Environmental constraints on lake sediment mineral compositions from the Tibetan Plateau and implications for paleoenvironment reconstruction JF - Journal of paleolimnolog N2 - Inorganic minerals form a major component of lacustrine sediments and have the potential to reveal detailed information on previous climatic and hydrological conditions. The ability to extract such information however, has been restricted by a limited understanding of the relationships between minerals and the environment. In an attempt to fill in this gap in our knowledge, 146 surface sediment samples have been investigated from 146 lakes on the Tibetan Plateau. The mineral compositions derived from these samples by X-Ray Diffraction (XRD) were used to examine the relationships between mineral compositions and the environmental variables determined for each site. Statistical techniques including Multivariate regression trees (MRT) and Redundancy Analysis (RDA), based on the mineral spectra and environmental variables, reveal that the electrical conductivity (EC) and Mg/Ca ratios of lake water are the most important controls on the composition of endogenic minerals. No endogenic minerals precipitate under hyper-fresh water conditions (EC lower than 0.13 mS/cm), with calcite commonly forming in water with EC values above 0.13 mS/cm. Between EC values of 0.13 and 26 mS/cm the mineral composition of lake sediments can be explained in terms of variations in the Mg/Ca ratio: calcite dominates at Mg/Ca ratios of less than 33, whereas aragonite commonly forms when the ratio is greater than 33. Where EC values are between 26 and 39 mS/cm, monohydrocalcite precipitates together with calcite and aragonite; above 39 mS/cm, gypsum and halite commonly form. Information on the local geological strata indicates that allogenic (detrital) mineral compositions are primarily influenced by the bedrock compositions within the catchment area. By applying these relationships to the late glacial and Holocene mineral record from Chaka Salt Lake, five lake stages have been identified and their associated EC conditions inferred. The lake evolved from a freshwater lake during the late glacial (before 11.4 cal. ka BP) represented by the lowest EC values (< 0.13 mS/cm), to a saline lake with EC values slightly higher than 39 mS/cm during the early and mid Holocene (ca. 11.4-5.3 cal. ka BP), and finally to a salt lake (after 5.3 cal. ka BP). These results illustrate the utility of our mineral-environmental model for the quantitative reconstruction of past environmental conditions from lake sediment records. KW - Mineral composition KW - XRD KW - Multivariate regression trees KW - Electrical conductivity KW - Paleolimnology KW - Tibetan Plateau Y1 - 2012 U6 - https://doi.org/10.1007/s10933-011-9549-2 SN - 0921-2728 VL - 47 IS - 1 SP - 71 EP - 85 PB - Springer CY - Dordrecht ER - TY - CHAP A1 - Ohl, Sven A1 - Brandt, S. A1 - Kliegl, Reinhold T1 - Post-saccadic location judgments after presentation of multiple target-like objects T2 - Perception Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 IS - 1 SP - 171 EP - 171 PB - Sage Publ. CY - London ER - TY - CHAP A1 - Laubrock, Jochen A1 - Cajar, Anke A1 - Engbert, Ralf T1 - Peripheral spatial frequency processing affects timing and metrics of saccades T2 - Perception Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 SP - 170 EP - 170 PB - Sage Publ. CY - London ER - TY - CHAP A1 - Krügel, Andre A1 - Engbert, Ralf T1 - Saccade targeting of spatially extended objects a Bayesian model T2 - Perception Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 SP - 167 EP - 167 PB - Sage Publ. CY - London ER - TY - CHAP A1 - Risse, Sarah T1 - Letter crowding and the benefit of parafoveal preview during reading T2 - Perception Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 SP - 133 EP - 133 PB - Sage Publ. CY - London ER - TY - CHAP A1 - Trukenbrod, Hans Arne A1 - Barthelme, S. A1 - Wichmann, Felix A. A1 - Engbert, Ralf T1 - Color does not guide eye movements: Evidence from a gaze-contingent experiment T2 - PERCEPTION Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 SP - 88 EP - 88 PB - PION LTD CY - LONDON ER - TY - CHAP A1 - Engbert, Ralf T1 - A computational model of microsaccadic responses to shifts of covert attention T2 - Perception Y1 - 2012 SN - 0301-0066 SN - 1468-4233 VL - 41 SP - 55 EP - 55 PB - Sage Publ. CY - London ER - TY - JOUR A1 - Hildebrandt, Niko A1 - Geissler, Daniel ED - Zahavy, E ED - Ordentlich, A ED - Yitzhaki, S ED - Shafferman, A T1 - Semiconductor quantum dots as FRET acceptors for multiplexed diagnostics and molecular ruler application JF - Advances in Experimental Medicine and Biology N2 - Applications based on Forster resonance energy transfer (FRET) play an important role for the determination of concentrations and distances within nanometer-scale systems in vitro and in vivo in many fields of biotechnology. Semiconductor nanocrystals (Quantum dots - QDs) possess ideal properties for their application as FRET acceptors when the donors have long excited state lifetimes and when direct excitation of QDs can be efficiently suppressed. Therefore, luminescent terbium complexes (LTCs) with excited state lifetimes of more than 2 ms are ideal FRET donor candidates for QD-acceptors. This chapter will give a short overview of theoretical and practical background of FRET, QDs and LTCs, and present some recent applications of LTC-QD FRET pairs for multiplexed ultra-sensitive in vitro diagnostics and nanometer-resolution molecular distance measurements. KW - Diagnostics KW - FRET KW - Imaging KW - Quantum dots KW - Terbium Y1 - 2012 SN - 978-94-007-2554-6 SN - 978-94-007-2555-3 U6 - https://doi.org/10.1007/978-94-007-2555-3_8 SN - 0065-2598 VL - 733 SP - 75 EP - 86 PB - Springer CY - Dordrecht ER - TY - JOUR A1 - Wellmann, Caroline A1 - Holzgrefe-Lang, Julia A1 - Truckenbrodt, Hubert A1 - Wartenburger, Isabell A1 - Höhle, Barbara T1 - How each prosodic boundary cue matters evidence from German infants JF - Frontiers in psychology N2 - Previous studies have revealed that infants aged 6-10 months are able to use the acoustic correlates of major prosodic boundaries, that is, pitch change, preboundary lengthening, and pause, for the segmentation of the continuous speech signal. Moreover, investigations with American-English- and Dutch-learning infants suggest that processing prosodic boundary markings involves a weighting of these cues. This weighting seems to develop with increasing exposure to the native language and to underlie crosslinguistic variation. In the following, we report the results of four experiments using the headturn preference procedure to explore the perception of prosodic boundary cues in German infants. We presented 8-month-old infants with a sequence of names in two different prosodic groupings, with or without boundary markers. Infants discriminated both sequences when the boundary was marked by all three cues (Experiment 1) and when it was marked by a pitch change and preboundary lengthening in combination (Experiment 2). The presence of a pitch change (Experiment 3) or preboundary lengthening (Experiment 4) as single cues did not lead to a successful discrimination. Our results indicate that pause is not a necessary cue for German infants. Pitch change and preboundary lengthening in combination, but not as single cues, are sufficient. Hence, by 8 months infants only rely on a convergence of boundary markers. Comparisons with adults' performance on the same stimulus materials suggest that the pattern observed with the 8-month-olds is already consistent with that of adults. We discuss our findings with respect to crosslinguistic variation and the development of a language-specific prosodic cue weighting. KW - infants KW - language acquisition KW - speech perception KW - prosodic bootstrapping KW - prosodic boundary cues KW - cue weighting KW - intonation phrase boundary KW - headturn preference procedure Y1 - 2012 U6 - https://doi.org/10.3389/fpsyg.2012.00580 SN - 1664-1078 VL - 3 PB - Frontiers Research Foundation CY - Lausanne ER -