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The present study explores the perceptual span, that is, the physical extent of the area from which useful visual information is obtained during a single fixation, during oral reading of Chinese sentences. Characters outside a window of legible text were replaced by visually similar characters. Results show that the influence of window size on the perceptual span was consistent across different fixation and oculomotor measures. To maintain normal reading behavior when reading aloud, it was necessary to have information provided from three characters to the right of the fixation. Together with findings from previous research, our findings suggest that the physical size of the perceptual span is smaller when reading aloud than in silent reading. This is in agreement with previous studies in English, suggesting that the mechanisms causing the reduced span in oral reading have a common base that generalizes across languages and writing systems.
BACKGROUND: The Achilles tendon (AT) requires optimal material and mechanical properties to function properly. Calculation of these properties depends on accurate measurement of input parameters (i.e. tendon elongation). However, the measurement of AT elongation with ultrasound during maximum voluntary isometric contraction (MVIC) is overestimated by ankle joint rotation (AJR). Methods to correct the influence of this rotation on AT elongation exist, yet their reproducibility in clinical settings is unknown. OBJECTIVE: To evaluate the test-retest reproducibility of AT elongation during MVIC after AJR correction. METHODS: Ten participants attended test and retest measurements where they performed plantar-flexion MVIC on a dynamometer. Simultaneously, ultrasound recorded AT elongation as the displacement of the medial gastrocnemius-myotendinous junction, while an electrogoniometer measured AJR. The ankle was then passively rotated to the AJR achieved during MVIC and AT elongation again determined. Elongation was corrected by subtracting this passive AT elongation from the total AT elongation during MVIC. Reproducibility was evaluated using ICC (2.1), test-retest variability (TRV, %), Bland-Altman analyses (Bias +/- LoA [1.96*SD]) and standard error of the measurement (SEM). RESULTS: Corrected AT elongation reproducibility exhibited an ICC = 0.79, SEM = 0.2 cm and TRV = 20 +/- 19%. Bias +/- LoA were determined to be 0.0 +/- 0.8 cm. CONCLUSIONS: Using this ultrasound and electrogoniometer-based method, corrected AT elongation can be assessed reproducibly.
Gamma-ray bursts (GRBs) are some of the Universe’s most enigmatic and exotic events. However, at energies above 10 GeV their behaviour remains largely unknown. Although space based telescopes such as the Fermi-LAT have been able to detect GRBs in this energy range, their photon statistics are limited by the small detector size. Such limitations are not present in ground based gamma-ray telescopes such as the H.E.S.S. experiment, which has now entered its second phase with the addition of a large 600 m2 telescope to the centre of the array. Such a large telescope allows H.E.S.S. to access the sub 100-GeV energy range while still maintaining a large effective collection area, helping to potentially probe the short timescale emission of these events.
We present a description of the H.E.S.S. GRB observation programme, summarising the performance of the rapid GRB repointing system and the conditions under which GRB observations are initiated. Additionally we will report on the GRB follow-ups made during the 2014-15 observation campaigns.
HESS J1826-130
(2017)
HESS J1826-130 is an unidentified hard spectrum source discovered by H.E.S.S. along the Galactic plane, the spectral index being Gamma = 1.6 with an exponential cut-off at about 12 TeV. While the source does not have a clear counterpart at longer wavelengths, the very hard spectrum emission at TeV energies implies that electrons or protons accelerated up to several hundreds of TeV are responsible for the emission. In the hadronic case, the VHE emission can be produced by runaway cosmic-rays colliding with the dense molecular clouds spatially coincident with the H.E.S.S. source.
In present-day German we find new word order options, particularly well-known from Turkish-German bilingual speakers in the contexts of new urban dialects, which allow violations of the canonical verb-second position in independent declarative clauses. In these cases, two positions are occupied in the forefield in front of the finite verb, usually by an adverbial and a subject, which identify, at the level of information structure, frame-setter and topic, respectively. Our study investigates the influence of verbal versus language -independent information-structural preferences for this linearisation, comparing Turkish-German multilingual speakers who have grown up in Germany with monolingual German and Turkish speakers. For tasks, in which grammatical restrictions were largely minimised, the results indicate a general tendency to place verbs in a position after the frame-setter and the topic; in addition, we found language-specific influences that distinguish Turkish-German and monolingual German speakers from monolingual Turkish ones. We interpret this as evidence for an information-structural motivation for verb-third, and for a clear dominance of German for Turkish-German speakers in Germany.
Nonalcoholic fatty liver disease (NAFLD) and nonalcoholic steatohepatitis (NASH) are hepatic manifestations of the metabolic syndrome. Many currently used animal models of NAFLD/NASH lack clinical features of either NASH or metabolic syndrome such as hepatic inflammation and fibrosis (e.g., high-fat diets) or overweight and insulin resistance (e.g., methionine-choline-deficient diets), or they are based on monogenetic defects (e.g., ob/ob mice). In the current study, a Western-type diet containing soybean oil with high n-6-PUFA and 0.75% cholesterol (SOD + Cho) induced steatosis, inflammation and fibrosis accompanied by hepatic lipid peroxidation and oxidative stress in livers of C57BL/6-mice, which in addition showed increased weight gain and insulin resistance, thus displaying a phenotype closely resembling all clinical features of NASH in patients with metabolic syndrome. In striking contrast, a soybean oil-containing Western-type diet without cholesterol (SOD) induced only mild steatosis but not hepatic inflammation, fibrosis, weight gain or insulin resistance. Another high-fat diet, mainly consisting of lard and supplemented with fructose in drinking water (LAD + Fru), resulted in more prominent weight gain, insulin resistance and hepatic steatosis than SOD + Cho, but livers were devoid of inflammation and fibrosis. Although both LAD + Fru-and SOD + Cho-fed animals had high plasma cholesterol, liver cholesterol was elevated only in SOD + Cho animals. Cholesterol induced expression of chemotactic and inflammatory cytokines in cultured Kupffer cells and rendered hepatocytes more susceptible to apoptosis. In summary, dietary cholesterol in the SOD + Cho diet may trigger hepatic inflammation and fibrosis. SOD + Cho-fed animals may be a useful disease model displaying many clinical features of patients with the metabolic syndrome and NASH.
In the picture-word interference paradigm, participants name pictures while ignoring a distractor word. When targets and distractors share phonemic and/or graphemic content, naming latencies are shorter than when there is no overlap between the two words. This study examines the hypothesis that the facilitation effect is modulated by differences in the time it takes participants to encode the picture name and process the distractor. Participants named pictures while ignoring distractors that either shared a phonological/orthographical syllable with the target word or were unrelated to that word. Response latencies during the naming of the distractors were collected and used as a measure of distractor processing time. The facilitation effect in picture naming was modulated by differences in response times between the picture and word naming tasks. This finding complements previous studies in showing that picture naming processes in the picture-word interference paradigm are influenced by the time course of distractor processing.
Modeling a secular trend by Monte Carlo simulation of height biased migration in a spatial network
(2017)
Background: In a recent Monte Carlo simulation, the clustering of body height of Swiss military conscripts within a spatial network with characteristic features of the natural Swiss geography was investigated. In this study I examined the effect of migration of tall individuals into network hubs on the dynamics of body height within the whole spatial network. The aim of this study was to simulate height trends. Material and methods: Three networks were used for modeling, a regular rectangular fishing net like network, a real world example based on the geographic map of Switzerland, and a random network. All networks contained between 144 and 148 districts and between 265-307 road connections. Around 100,000 agents were initially released with average height of 170 cm, and height standard deviation of 6.5 cm. The simulation was started with the a priori assumption that height variation within a district is limited and also depends on height of neighboring districts (community effect on height). In addition to a neighborhood influence factor, which simulates a community effect, body height dependent migration of conscripts between adjacent districts in each Monte Carlo simulation was used to re-calculate next generation body heights. In order to determine the direction of migration for taller individuals, various centrality measures for the evaluation of district importance within the spatial network were applied. Taller individuals were favored to migrate more into network hubs, backward migration using the same number of individuals was random, not biased towards body height. Network hubs were defined by the importance of a district within the spatial network. The importance of a district was evaluated by various centrality measures. In the null model there were no road connections, height information could not be delivered between the districts. Results: Due to the favored migration of tall individuals into network hubs, average body height of the hubs, and later, of the whole network increased by up to 0.1 cm per iteration depending on the network model. The general increase in height within the network depended on connectedness and on the amount of height information that was exchanged between neighboring districts. If higher amounts of neighborhood height information were exchanged, the general increase in height within the network was large (strong secular trend). The trend in the homogeneous fishnet like network was lowest, the trend in the random network was highest. Yet, some network properties, such as the heteroscedasticity and autocorrelations of the migration simulation models differed greatly from the natural features observed in Swiss military conscript networks. Autocorrelations of district heights for instance, were much higher in the migration models. Conclusion: This study confirmed that secular height trends can be modeled by preferred migration of tall individuals into network hubs. However, basic network properties of the migration simulation models differed greatly from the natural features observed in Swiss military conscripts. Similar network-based data from other countries should be explored to better investigate height trends with Monte Carlo migration approach.
The aim of the study was to investigate the correlation of heights of conscripts living in neighboring districts in Poland. The study used 10% of a nationally representative sample of 26,178 males 18.5-19.5 years old examined during the National survey of Polish conscripts conducted in 2001. The sample represented all regions and social strata of the country and included 354 different districts within 16 voivodships (provinces). Analyses were performed with the R statistical software. A small but significant correlation (0.24, p < 0.0001) was observed for height between 1st order neighboring districts. Correlations decreased with increased distances between neighboring districts, but remained significant for 7th node neighbors (0.18, p < 0.0001). Regarding voivodships (provinces), average height showed a geographical trend from the northwest (relatively tall) to the southeast (relatively short), and the correlation was stronger for first order neighboring provinces (0.796, p < 0.001). This study revealed clusters of tall people and short people, providing a support for hypothesis of the community effect in height. Small correlations between 1st order neighbors than in another country (Switzerland) may be associated with differences in geography, since in Poland there are no natural barriers (e.g., mountains) and road infrastructure is well-developed.
Background: We investigated height of Norwegian conscripts in view of the hypothesis of a "community effect on height" using autocorrelation analysis of district heights within a time-span of 20 years at the end of the 19th century and correlations between neighboring districts at this time. Material and methods: After digitalizing available body height data of Norwegian draftees in 1877-1878, 1880 (averaged as 1878), and 1895-1897 (averaged as 1896) we calculated the magnitude of autocorrelation of body height within the same municipality at different time points. Furthermore, we generated three different neighborhood networks, (1) based on Euclidean distances, (2) a minimum spanning tree build on those distances, (3) a network founded on real world road connections. The networks were used to determine the correlation between body height of neighboring districts depending on the number of edges required to connect two municipalities. Results: The autocorrelation value for body heights was around r = 0.5 (for all p < 0.001) in the years 1878 and 1896. The correlation between neighboring districts varied in the Euclidean distance based network between 0.47 and 0.27 approximately for both years in a sorted order, descending from nearest (0-50 km) to farthest (150-200 km, for all p < 0.001). First order neighbors in the minimum spanning tree network correlation was 0.36 in 1878 and 0.42 in 1896 (for all p < 0.001). The values of neighbor correlation in the road connection based network ranged in 1878 from 0.42 (first order neighbors) to 0.17 (forth order neighbors, for all p < 0.01) and in 1896 from 0.46 (first order neighbors) to 0.12 (forth order neighbors, for all p < 0.05). Conclusion: This initial study of Norwegian conscript height data from the 19th century showed significant medium sized effects for the within district autocorrelation between 1878 and 1896 as well as medium neighborhood correlation, slightly lower in comparison to a recent study regarding Swiss conscripts. Digitalizing more data from other years in this and later time spans as well as using older road and ship connections instead of the actual road data might stabilize and improve those findings.
The 1911 Chon-Kemin (Kebin) earthquake culminated c. 30 years of remarkable earthquakes in the northern Tien Shan (Kyrgyzstan and Kazakhstan). Building on prior mapping of the event, we traced its rupture in the field and measured more than 50 offset landforms. Cumulative fault rupture length is >155-195 km along 13 fault patches comprising six sections. The patches are separated by changes of dip magnitude or dip direction, or by 4-10 km-wide stepovers. One <40 km section overlaps and is parallel to the main north-dipping rupture but is 7 km north and dips opposite (south). Both ends of the rupture are along mountain front thrust faults demonstrating late Quaternary activity. We computed the moment from each fault patch using the surface fault traces, dip inferred from the traces, 20 km seismogenic thickness, rigidity of 3.3 x 10(10) N m(-2) and dip slip converted from our observations of the largely reverse sense of motion vertical offsets. The discontinuous patches with c. 3-4 m average slip and peak slip of <14 m yield a seismic moment of 4.6 x 10(20) Nm (M-w 7.78) to 7.4 x 10(20) Nm (M-w 7.91). The majority of moment was released along the inner eastern rupture segments. This geological moment is lower by a factor of 1.5 from that determined from teleseismic data.
The Lower Rhine Graben (Central Europe) is a prime example of a seismically active low-strain rift zone characterized by pronounced anthropogenic and climatic overprint of structures, and long recurrence intervals of large earthquakes. These factors render the identification of active faults and surface ruptures difficult. We investigated two fault scarps in the Lower Rhine Graben, to decipher their structural character, offset and potential seismogenic origin. Both scarps were modified by anthropogenic activity. The Hemmerich site lies c. 20 km SW of Cologne, along the Erft Fault. The Untermaubach site lies SW of Duren, where the Schafberg Fault projects into the Rur River valley. At the Hemmerich site, geomorphic and geophysical data, as well as exploratory coring reveal evidence of repeated normal faulting. Geophysical analysis and palaeoseismological excavation at the Untermaubach site reveal a complex fault zone in Holocene gravels characterized by subtle gravel deformation. Differentiation of tectonic and fluvial features was only possible with trenching, because fault structures and grain sizes of the sediments were below the resolution of the geophysical data. Despite these issues, our investigation demonstrates that valuable insight into past earthquakes and seismogenic deformation in a low-strain environment can be revealed using a multidisciplinary approach.
A series of large-magnitude earthquakes above 6.9 occurred in the northern Tien-Shan between 1885 and 1911. The Chilik earthquake of 11 July 1889, has been listed with a magnitude of 8.3, based on sparse macroseismic intensities, constrained by reported damage. Despite the existence of several juvenile fault scarps in the epicentral region, that are possibly associated with the 1889 earthquake, no through-going surface rupture having the dimensions expected for a magnitude 8.3 earthquake has been located - a puzzling dilemma. Could the magnitude have been overestimated? This would have major implications not only for the understanding of the earthquake series, but also for regional hazard estimates. Fortunately, a fragmentary record from an early Rebeur-Paschwitz seismometer exists for the Chilik event, recorded in Wilhelmshaven (Germany). To constrain the magnitude, we compare the late coda waves of this record with those of recent events from Central Asia, recorded on modern instruments in Germany and filtered with Rebeur-Paschwitz instrument characteristics. Additional constraints come from disturbances of historic magnetograms that exist from the Chilik and the 1911 Chon-Kemin earthquakes. Scaling of these historic records confirm a magnitude of about 8 for the 1889 Chilik earthquake, pointing towards a lower crustal contribution to the fault area.
The knowledge of the largest expected earthquake magnitude in a region is one of the key issues in probabilistic seismic hazard calculations and the estimation of worst-case scenarios. Earthquake catalogues are the most informative source of information for the inference of earthquake magnitudes. We analysed the earthquake catalogue for Central Asia with respect to the largest expected magnitudes m(T) in a pre-defined time horizon T-f using a recently developed statistical methodology, extended by the explicit probabilistic consideration of magnitude errors. For this aim, we assumed broad error distributions for historical events, whereas the magnitudes of recently recorded instrumental earthquakes had smaller errors. The results indicate high probabilities for the occurrence of large events (M >= 8), even in short time intervals of a few decades. The expected magnitudes relative to the assumed maximum possible magnitude are generally higher for intermediate-depth earthquakes (51-300 km) than for shallow events (0-50 km). For long future time horizons, for example, a few hundred years, earthquakes with M >= 8.5 have to be taken into account, although, apart from the 1889 Chilik earthquake, it is probable that no such event occurred during the observation period of the catalogue.
Intraplate seismicity is often characterized by episodic, clustered and migrating earthquakes and extended after-shock sequences. Can these observations - primarily from North America, China and Australia - usefully be applied to seismic hazard assessment for intraplate Europe? Existing assessments are based on instrumental and historical seismicity of the past c. 1000 years, as well as some data for active faults. This time span probably fails to capture typical large-event recurrence intervals of the order of tens of thousands of years. Palaeoseismology helps to lengthen the observation window, but preferentially produces data in regions suspected to be seismically active. Thus the expected maximum magnitudes of future earthquakes are fairly uncertain, possibly underestimated, and earthquakes are likely to occur in unexpected locations. These issues particularly arise in considering the hazards posed by low-probability events to both heavily populated areas and critical facilities. For example, are the variations in seismicity (and thus assumed seismic hazard) along the Rhine Graben a result of short sampling or are they real? In addition to a better assessment of hazards with new data and models, it is important to recognize and communicate uncertainties in hazard estimates. The more users know about how much confidence to place in hazard maps, the more effectively the maps can be used.
Palaeoseismic records and seismological data from continental interiors increasingly show that these areas of slow strain accumulation are more subject to seismic and associated natural hazards than previously thought. Moreover, some of our instincts developed for assessing hazards at plate boundaries might not apply here. Hence assessing hazards and drawing implications for the future is challenging, and how well it can be done heavily depends on the ability to assess the spatiotemporal distribution of past large earthquakes. This book explores some key issues in understanding hazards in slowly deforming areas. Examples include classic intraplate regions, such as Central and Northern Europe, Mongolia, Inner Mongolia, Australia, and North and South America, and regions of widely distributed strain, such as the Tien Shan Mountains in Central Asia. The papers in this volume are grouped into two sections. The first section deals with instrumental and historical earthquake data and associated hazard assessments. The second section covers methods from structural geology, palaeoseismology and tectonic geomorphology, and incorporates field evidence
Plant Hormones
(2017)
This volume aims to present a representative cross-section of modern experimental approaches relevant to Plant Hormone Biology, ranging from relatively simple physiological to highly sophisticated methods. Chapters describe physiological, developmental, microscopy-based techniques, measure hormone contents, and heterologous systems. Written in the highly successful Methods in Molecular Biology series format, chapters include introductions to their respective topics, lists of the necessary materials and reagents, step-by-step, readily reproducible laboratory protocols, and tips on troubleshooting and avoiding known pitfalls.
Preface
(2017)
Artificial light harvesting complexes find applications in artificial photosynthesis, photovoltaics and light harvesting chemical sensors. They are used to enhance the absorption of light of a reaction center which is often represented by a single acceptor. Here, we present different light harvesting systems on DNA origami structures and analyze systematically the light harvesting efficiency. By changing the number and arrangement of different fluorophores (FAM as donor, Cy3 as transmitter and Cy5 as acceptor molecules) the light harvesting efficiency is optimized to create a broadband absorption and to improve the antenna effect 1 (including two energy transfer steps) from 0.02 to 1.58, and the antenna effect 2 (including a single energy transfer step) from 0.04 to 8.7, i.e. the fluorescence emission of the acceptor is significantly higher when the light-harvesting antenna is excited at lower wavelength compared to direct excitation of the acceptor. The channeling of photo energy to the acceptor proceeds by Forster Resonance Energy Transfer (FRET) and we carefully analyze also the FRET efficiency of the different light harvesting systems. Accordingly, the antenna effect can be tuned by modifying the stoichiometry of donor, transmitter and acceptor dyes, whereas the FRET efficiency is mainly governed by the spectroscopic properties of dyes and their distances.