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Several chronometric biases in numerical cognition have informed our understanding of a mental number line (MNL). Complementing this approach, we investigated spatial performance in a magnitude comparison task. Participants located the larger or smaller number of a pair on a horizontal line representing the interval from 0 to 10. Experiments 1 and 2 used only number pairs one unit apart and found that digits were localized farther to the right with "select larger" instructions than with "select smaller" instructions. However, when numerical distance was varied (Experiment 3), digits were localized away from numerically near neighbors. This repulsion effect reveals context-specific distortions in number representation not previously noticed with chronometric measures.
Integrated and concurrent cultures in rice fields are a promising approach to sustainable farming as the demand for aquacultural and agricultural products continues to grow while land and water resources become increasingly scarce. Prawn farming mainly takes place in coastal regions in improved extensive to semi-intensive aquacultures but a trend to shift the industry to inland regions has been noticed. This inland study in Northern Bangladesh used different input regimes such as fertilizer and additional feed to compare the performance of prawn and fish in flooded paddy fields in regard to water quality measurements. Maximal net yields and body weight gain with minimized negative impact on water quality were found when initial body weights of prawn were optimized. Regarding yield factors in reference to the reduction of costs due to the avoidance of expensive fertilizer/feed and effort, prawn performed better than integrated fish cultures considering a higher market value of prawn with net yields of up to 97 +/- 55 kg ha(-1) for unfed and 151 +/- 61 kg ha(-1) for fed treatments. Rice yields of up to 4.7 +/- 0.1 t ha(-1) for unfed and 4.4 +/- 0.1 t ha(-1) were achieved for fed treatments. The findings suggest that for small scale farmers, prawn cum rice cultures are an economically profitable and comparatively easily manageable alternative to rice cum fish cultures.
Two optically obscured Wolf-Rayet (WR) stars have been recently discovered by means of their infrared (IR) circumstellar shells, which show signatures of interaction with each other. Following the systematics of the WR star catalogues, these stars obtain the names WR 120bb and WR 120bc. In this paper, we present and analyse new near-IR, J-, H- and K-band spectra using the Potsdam Wolf-Rayet model atmosphere code. For that purpose, the atomic data base of the code has been extended in order to include all significant lines in the near-IR bands.
The spectra of both stars are classified as WN9h. As their spectra are very similar the parameters that we obtained by the spectral analyses hardly differ. Despite their late spectral subtype, we found relatively high stellar temperatures of 63 kK. The wind composition is dominated by helium, while hydrogen is depleted to 25 per cent by mass.
Because of their location in the Scutum-Centaurus Arm, WR 120bb and WR 120bc appear highly reddened, A(Ks) approximate to 2 mag. We adopt a common distance of 5.8 kpc to both stars, which complies with the typical absolute K-band magnitude for the WN9h subtype of -6.5 mag, is consistent with their observed extinction based on comparison with other massive stars in the region, and allows for the possibility that their shells are interacting with each other. This leads to luminosities of log(L/L-circle dot) = 5.66 and 5.54 for WR 120bb and WR 120bc, with large uncertainties due to the adopted distance.
The values of the luminosities of WR 120bb and WR 120bc imply that the immediate precursors of both stars were red supergiants (RSG). This implies in turn that the circumstellar shells associated with WR 120bb and WR 120bc were formed by interaction between the WR wind and the dense material shed during the preceding RSG phase.
Management of data to produce scientific knowledge is a key challenge for biological research in the 21st century. Emerging high-throughput technologies allow life science researchers to produce big data at speeds and in amounts that were unthinkable just a few years ago. This places high demands on all aspects of the workflow: from data capture (including the experimental constraints of the experiment), analysis and preservation, to peer-reviewed publication of results. Failure to recognise the issues at each level can lead to serious conflicts and mistakes; research may then be compromised as a result of the publication of non-coherent protocols, or the misinterpretation of published data. In this report, we present the results from a workshop that was organised to create an ontological data-modelling framework for Laboratory Protocol Standards for the Molecular Methods Database (MolMeth). The workshop provided a set of short- and long-term goals for the MolMeth database, the most important being the decision to use the established EXACT description of biomedical ontologies as a starting point.
We tested the limits of working-memory capacity (WMC) of young adults, old adults, and children with a memory-updating task. The task consisted of mentally shifting spatial positions within a grid according to arrows, their color signaling either only go (control) or go/no-go conditions. The interference model (IM) of Oberauer and Kliegl (2006) was simultaneously fitted to the data of all groups. In addition to the 3 main model parameters (feature overlap, noise, and processing rate), we estimated the time for switching between go and no-go steps as a new model parameter. In this study, we examined the IM parameters across the life span. The IM parameter estimates show that (a) conditions were not different in interference by feature overlap and interference by confusion; (b) switching costs time; (c) young adults and children were less susceptible than old adults to interference due to feature overlap; (d) noise was highest for children, followed by old and young adults; (e) old adults differed from children and young adults in lower processing rate; and (f) children and old adults had a larger switch cost between go steps and no-go steps. Thus, the results of this study indicated that across age, the IM parameters contribute distinctively for explaining the limits of WMC.
Deserts are a major source of loess and may undergo substantial wind-erosion as evidenced by yardang fields, deflation pans, and wind-scoured bedrock landscapes. However, there are few quantitative estimates of bedrock removal by wind abrasion and deflation. Here, we report wind-erosion rates in the western Qaidam Basin in central China based on measurements of cosmogenic Be-10 in exhumed Miocene sedimentary bedrock. Sedimentary bedrock erosion rates range from 0.05 to 0.4 mm/yr, although the majority of measurements cluster at 0.125 +/- 0.05 mm/yr. These results, combined with previous work, indicate that strong winds, hyper-aridity, exposure of friable Neogene strata, and ongoing rock deformation and uplift in the western Qaidam Basin have created an environment where wind, instead of water, is the dominant agent of erosion and sediment transport. Its geographic location (upwind) combined with volumetric estimates suggest that the Qaidam Basin is a major source (up to 50%) of dust to the Chinese Loess Plateau to the east. The cosmogenically derived wind erosion rates are within the range of erosion rates determined from glacial and fluvial dominated landscapes worldwide, exemplifying the effectiveness of wind to erode and transport significant quantities of bedrock.
Matrix product states and their continuous analogues are variational classes of states that capture quantum many-body systems or quantum fields with low entanglement; they are at the basis of the density-matrix renormalization group method and continuous variants thereof. In this work we show that, generically, N-point functions of arbitrary operators in discrete and continuous translation invariant matrix product states are completely characterized by the corresponding two- and three-point functions. Aside from having important consequences for the structure of correlations in quantum states with low entanglement, this result provides a new way of reconstructing unknown states from correlation measurements, e. g., for one-dimensional continuous systems of cold atoms. We argue that such a relation of correlation functions may help in devising perturbative approaches to interacting theories.
A survey has been carried out in the Computer Science (CS) department at the University of Baghdad to investigate the attitudes of CS students in a female dominant environment, showing the differences between male and female students in different academic years. We also compare the attitudes of the freshman students of two different cultures (University of Baghdad, Iraq, and the University of Potsdam).
In this paper we report on our experiments in teaching computer science concepts with a mix of tangible and abstract object manipulations. The goal we set ourselves was to let pupils discover the challenges one has to meet to automatically manipulate formatted text. We worked with a group of 25 secondary school pupils (9-10th grade), and they were actually able to “invent” the concept of mark-up language. From this experiment we distilled a set of activities which will be replicated in other classes (6th grade) under the guidance of maths teachers.
We know exactly what you want the development of a completely individualised conjoint analysis
(2013)
Improving the predictive validity of conjoint analysis has been an important research objective for many years. Whereas the majority of attempts have been different approaches to preference modelling, data collection or product presentation, only a few scholars have tried to improve predictive validity by individualising conjoint designs. This comes as a surprise because many markets have observed an augmented demand for customised products and highly heterogeneous customers' preferences. Against this background, the authors develop a conjoint variant based on a completely individualised conjoint design. More concretely, the new approach not only individualises the attributes, but also the attribute levels. The results of a comprehensive empirical study yield a significantly higher validity than existing standardised-level conjoint approaches. Consequently, they help marketers to gain deeper insights into their customers' preferences.
The dynamics of external contributions to the geomagnetic field is investigated by applying time-frequency methods to magnetic observatory data. Fractal models and multiscale analysis enable obtaining maximum quantitative information related to the short-term dynamics of the geomagnetic field activity. The stochastic properties of the horizontal component of the transient external field are determined by searching for scaling laws in the power spectra. The spectrum fits a power law with a scaling exponent beta, a typical characteristic of self-affine time-series. Local variations in the power-law exponent are investigated by applying wavelet analysis to the same time-series. These analyses highlight the self-affine properties of geomagnetic perturbations and their persistence. Moreover, they show that the main phases of sudden storm disturbances are uniquely characterized by a scaling exponent varying between 1 and 3, possibly related to the energy contained in the external field. These new findings suggest the existence of a long-range dependence, the scaling exponent being an efficient indicator of geomagnetic activity and singularity detection. These results show that by using magnetogram regularity to reflect the magnetosphere activity, a theoretical analysis of the external geomagnetic field based on local power-law exponents is possible.
The expansion and intensification of soya bean agriculture in southeastern Amazonia can alter watershed hydrology and biogeochemistry by changing the land cover, water balance and nutrient inputs. Several new insights on the responses of watershed hydrology and biogeochemistry to deforestation in Mato Grosso have emerged from recent intensive field campaigns in this region. Because of reduced evapotranspiration, total water export increases threefold to fourfold in soya bean watersheds compared with forest. However, the deep and highly permeable soils on the broad plateaus on which much of the soya bean cultivation has expanded buffer small soya bean watersheds against increased stormflows. Concentrations of nitrate and phosphate do not differ between forest or soya bean watersheds because fixation of phosphorus fertilizer by iron and aluminium oxides and anion exchange of nitrate in deep soils restrict nutrient movement. Despite resistance to biogeochemical change, streams in soya bean watersheds have higher temperatures caused by impoundments and reduction of bordering riparian forest. In larger rivers, increased water flow, current velocities and sediment flux following deforestation can reshape stream morphology, suggesting that cumulative impacts of deforestation in small watersheds will occur at larger scales.
Background.Vocational interests play a central role in the vocational decision-making process and are decisive for the later job satisfaction and vocational success. Based on Ackerman's (1996) notion of trait complexes, specific interest profiles of gifted high-school graduates can be expected. Aims.Vocational interests of gifted and highly achieving adolescents were compared to those of their less intelligent/achieving peers according to Holland's (1997) RIASEC model. Further, the impact of intelligence and achievement on interests were analysed while statistically controlling for potentially influencing variables. Changes in interests over time were investigated. Sample.N= 4,694 German students (age: M= 19.5, SD= .80; 54.6% females) participated in the study (TOSCA; Koller, Watermann, Trautwein, & Ludtke, 2004). Method. Interests were assessed in participants' final year at school and again 2 years later (N= 2,318). Results.Gifted participants reported stronger investigative and realistic interests, but lower social interests than less intelligent participants. Highly achieving participants reported higher investigative and (in wave 2) higher artistic interests. Considerable gender differences were found: gifted girls had a flat interest profile, while gifted boys had pronounced realistic and investigative and low social interests. Multilevel multiple regression analyses predicting interests by intelligence and school achievement revealed stable interest profiles. Beyond a strong gender effect, intelligence and school achievement each contributed substantially to the prediction of vocational interests. Conclusions.At the time around graduation from high school, gifted young adults show stable interest profiles, which strongly differ between gender and intelligence groups. These differences are relevant for programmes for the gifted and for vocational counselling.
Two experiments investigated (1) how activation of manual affordances is triggered by visual and linguistic cues to manipulable objects and (2) whether graspable object parts play a special role in this process. Participants pressed a key to categorize manipulable target objects copresented with manipulable distractor objects on a computer screen. Three factors were varied in Experiment 1: (1) the target's and (2) the distractor's handles' orientation congruency with the lateral manual response and (3) the Visual Focus on one of the objects. In Experiment 2, a linguistic cue factor was added to these three factors-participants heard the name of one of the two objects prior to the target display onset. Analysis of participants' motor and oculomotor behaviour confirmed that perceptual and linguistic cues potentiated activation of grasp affordances. Both target- and distractor-related affordance effects were modulated by the presence of visual and linguistic cues. However, a differential visual attention mechanism subserved activation of compatibility effects associated with target and distractor objects. We also registered an independent implicit attention attraction effect from objects' handles, suggesting that graspable parts automatically attract attention during object viewing. This effect was further amplified by visual but not linguistic cues, thus providing initial evidence for a recent hypothesis about differential roles of visual and linguistic information in potentiating stable and variable affordances (Borghi in Language and action in cognitive neuroscience. Psychology Press, London, 2012).
We easily recover the causal properties of visual events, enabling us to understand and predict changes in the physical world. We see a tennis racket hitting a ball and sense that it caused the ball to fly over the net; we may also have an eerie but equally compelling experience of causality if the streetlights turn on just as we slam our car's door. Both perceptual [1] and cognitive [2] processes have been proposed to explain these spontaneous inferences, but without decisive evidence one way or the other, the question remains wide open [3-8]. Here, we address this long-standing debate using visual adaptation-a powerful tool to uncover neural populations that specialize in the analysis of specific visual features [9-12]. After prolonged viewing of causal collision events called "launches" [1], subsequently viewed events were judged more often as noncausal. These negative aftereffects of exposure to collisions are spatially localized in retinotopic coordinates, the reference frame shared by the retina and visual cortex. They are not explained by adaptation to other stimulus features and reveal visual routines in retinotopic cortex that detect and adapt to cause and effect in simple collision stimuli.
Two images, taken by the Cassini spacecraft near Saturn's equinox in 2009 August, show the Earhart propeller casting a 350 km long shadow, offering the opportunity to watch how the ring height, excited by the propeller moonlet, relaxes to an equilibrium state. From the shape of the shadow cast and a model of the azimuthal propeller height relaxation, we determine the exponential cooling constant of this process to be lambda = 0.07 +/- 0.02 km(-1), and thereby determine the collision frequency of the ring particles in the vertically excited region of the propeller to be omega(c)/Omega = 0.9 +/- 0.2.
We report results from TeV gamma-ray observations of the microquasar Cygnus X-3. The observations were made with the Very Energetic Radiation Imaging Telescope Array System (VERITAS) over a time period from 2007 June 11 to 2011 November 28. VERITAS is most sensitive to gamma rays at energies between 85 GeV and 30 TeV. The effective exposure time amounts to a total of about 44 hr, with the observations covering six distinct radio/X-ray states of the object. No significant TeV gamma-ray emission was detected in any of the states, nor with all observations combined. The lack of a positive signal, especially in the states where GeV gamma rays were detected, places constraints on TeV gamma-ray production in Cygnus X-3. We discuss the implications of the results.
This article examines two so-far-understudied verb doubling constructions in Mandarin Chinese, viz., verb doubling clefts and verb doubling lianaEuro broken vertical bar dou. We show that these constructions have the same internal syntax as regular clefts and lianaEuro broken vertical bar dou sentences, the doubling effect being epiphenomenal; therefore, we classify them as subtypes of the general cleft and lianaEuro broken vertical bar dou constructions, respectively, rather than as independent constructions. Additionally, we also show that, as in many other languages with comparable constructions, the two instances of the verb are part of a single movement chain, which has the peculiarity of allowing Spell-Out of more than one link.
The human face shows individual features and features that are characteristic for sex and age (the loss of childlike characteristics during maturation). The analysis of facial dimensions is essential for identifying individual features also for forensic issues.
The analysis of facial proportions was performed on photogrammetric data from front views of 125 children. The data were pooled from 2 different studies. The children's data were obtained from a longitudinal study and reduced by random generator to ensure the data of adults from a separate cross-sectional study.
We applied principal component analysis on photogrammetric facial proportions of 169 individuals: 125 children (63 boys and 62 girls) aged 2-7 years and 44 adults (18 men and 26 women) aged 18-65 years.
Facial proportions depend on age and sex. Three components described age: (1) proportions of facial height to head height, (2) proportions that involve endocanthal breadth, and (3) bigonial to bizygonial proportions. Proportions that associate with sex are connected with nasal distances and nasal to bizygonial distances.
Twenty-three percent of the variance, particularly variance that are connected with proportions of lower and middle face heights to head height, do neither depend on sex nor on age and thus appear useful for screening purposes, eg, for dysmorphic genetic syndromes.
Value creation in scene-based music production - the case of electronic club music in Germany
(2013)
The focus of this article is on the variability of value creation in the popular music industry. Recent trends in electronic music have been based on both the valorization of global tastes and of local specialities in performance and production. Depending on musical styles and market niches, local scenes have become important forces behind heterogeneous globalocal markets. At the same time, technological change and the virtualization of music production and distribution contribute to increasingly differentiated configurations of value creation. It is therefore necessary to reconstruct theoretically and empirically the new interplay among the local music production, digital media markets, and virtual communities that are involved. On the basis of empirical explorations in a German hot spot of electronic club-music production (the city of Berlin), the article indentifies local interaction practice and constellations of stakeholders. The findings show that value creation in these rapidly changing production scenes has moved away from the large-scale distribution of producer-induced media to audience-induced live performance and interactive soundtrack production. This change involves the rising importance of cultural embeddings such as taste building, reputation building among artists and producers, and local community building. Starting from an open theoretical problematization of value creation with regard to fluid scenes and shifting modes of production, the results of first empirical reconstructions are taken as inputs to an evolving discussion on the configurations of value creation in consumer-based strands of music production.
From 6 to 9 August 2012, intense rainfall hit the northern Philippines, causing massive floods in Metropolitan Manila and nearby regions. Local rain gauges recorded almost 1000mm within this period. However, the recently installed Philippine network of weather radars suggests that Metropolitan Manila might have escaped a potentially bigger flood just by a whisker, since the centre of mass of accumulated rainfall was located over Manila Bay. A shift of this centre by no more than 20 km could have resulted in a flood disaster far worse than what occurred during Typhoon Ketsana in September 2009.
The challenge is providing teachers with the resources they need to strengthen their instructions and better prepare students for the jobs of the 21st Century. Technology can help meet the challenge. Teachers’ Tryscience is a noncommercial offer, developed by the New York Hall of Science, TeachEngineering, the National Board for Professional Teaching Standards and IBM Citizenship to provide teachers with such resources. The workshop provides deeper insight into this tool and discussion of how to support teaching of informatics in schools.
Scientific writing is an important skill for computer science and computer engineering professionals. In this paper we present a writing concept across the curriculum program directed towards scientific writing. The program is built around a hierarchy of learning outcomes. The hierarchy is constructed through analyzing the learning outcomes in relation to competencies that are needed to fulfill them.
Isolation of recombinant antibodies from antibody libraries is commonly performed by different molecular display formats including phage display and ribosome display or different cell-surface display formats. We describe a new method which allows the selection of Escherichia coil cells producing the required single chain antibody by cultivation in presence of ampicillin conjugated to the antigen of interest. The method utilizes the neutralization of the conjugate by the produced single chain antibody which is secreted to the periplasm. Therefore, a new expression system based on the pET26b vector was designed and a library was constructed. The method was successfully established first for the selection of E. coli BL21 Star (DE3) cells expressing a model single chain antibody (anti-fluorescein) by a simple selection assay on LB-agar plates. Using this selection assay, we could identify a new single chain antibody binding biotin by growing E. coil BL21 Star (DE3) containing the library in presence of a biotin-ampicillin conjugate. In contrast to methods as molecular or cell surface display our selection system applies the soluble single chain antibody molecule and thereby avoids undesired effects, e.g. by the phage particle or the yeast fusion protein. By selecting directly in an expression strain, production and characterization of the selected single chain antibody is possible without any further cloning or transformation steps.
1. Porter strategic competitive analysis 2. A Porter analysis of the competitive advantage of banks in business lending and proprietary trading 3. Summary, competitive advantage of banks in business lending and proprietary trading 4. JPMorgan’s “London Whale” speculation 5. A common misapprehension about hedged positions in corporate debt 6. Conclusion
Assessing diversity is among the major tasks in ecology and conservation science. In ecological and conservation studies, epiphytic cryptogams are usually sampled up to accessible heights in forests. Thus, their diversity, especially of canopy specialists, likely is underestimated. If the proportion of those species differs among forest types, plot-based diversity assessments are biased and may result in misleading conservation recommendations. We sampled bryophytes and lichens in 30 forest plots of 20 m x 20 m in three German regions, considering all substrates, and including epiphytic litter fall. First, the sampling of epiphytic species was restricted to the lower 2 m of trees and shrubs. Then, on one representative tree per plot, we additionally recorded epiphytic species in the crown, using tree climbing techniques. Per tree, on average 54% of lichen and 20% of bryophyte species were overlooked if the crown was not been included. After sampling all substrates per plot, including the bark of all shrubs and trees, still 38% of the lichen and 4% of the bryophyte species were overlooked if the tree crown of the sampled tree was not included. The number of overlooked lichen species varied strongly among regions. Furthermore, the number of overlooked bryophyte and lichen species per plot was higher in European beech than in coniferous stands and increased with increasing diameter at breast height of the sampled tree. Thus, our results indicate a bias of comparative studies which might have led to misleading conservation recommendations of plot-based diversity assessments.
Through the reactions of 1-aminomethyl-2-naphthol and substituted 1-aminobenzyl-2-naphthols with 3,4-dihydroisoquinoline or 6,7-dimethoxy-3,4-dihydroisoquinoline under microwave conditions, naphth[1,2-e][1,3]oxazino[2,3-a]-isoquinoline derivatives were prepared in good yields. The latter reaction was extended by using 2-aminoarylmethyl-1-naphthols, leading to isomeric naphth-[2,1-e][1,3]oxazino[2,3-a] isoquinolines. Beside the detailed NMR spectroscopic and theoretical study of both stereochemistry and dynamic behaviour of these new conformational flexible heterocyclic ring systems an unexpected dynamic process between two diastereomers was observed in solution, studied by variable temperature H-1 NMR spectroscopy and the mechanism proved by theoretical DFT computations.
We investigate the temporal and spectral correlations between flux and anisotropy fluctuations of TeV-band cosmic rays in light of recent data taken with IceCube. We find that for a conventional distribution of cosmic-ray sources, the dipole anisotropy is higher than observed, even if source discreteness is taken into account. Moreover, even for a shallow distribution of galactic cosmic-ray sources and a reacceleration model, fluctuations arising from source discreteness provide a probability only of the order of 10% that the cosmic-ray anisotropy limits of the recent IceCube analysis are met. This probability estimate is nearly independent of the exact choice of source rate, but generous for a large halo size. The location of the intensity maximum far from the Galactic Center is naturally reproduced.
Beta diversity is a conceptual link between diversity at local and regional scales. Various additional methodologies of quantifying this and related phenomena have been applied. Among them, measures of pairwise (dis)similarity of sites are particularly popular. Undersampling, i.e. not recording all taxa present at a site, is a common situation in ecological data. Bias in many metrics related to beta diversity must be expected, but only few studies have explicitly investigated the properties of various measures under undersampling conditions. On the basis of an empirical data set, representing near-complete local inventories of the Lepidoptera from an isolated Pacific island, as well as simulated communities with varying properties, we mimicked different levels of undersampling. We used 14 different approaches to quantify beta diversity, among them dataset-wide multiplicative partitioning (i.e. true beta diversity') and pairwise site x site dissimilarities. We compared their values from incomplete samples to true results from the full data. We used these comparisons to quantify undersampling bias and we calculated correlations of the dissimilarity measures of undersampled data with complete data of sites. Almost all tested metrics showed bias and low correlations under moderate to severe undersampling conditions (as well as deteriorating precision, i.e. large chance effects on results). Measures that used only species incidence were very sensitive to undersampling, while abundance-based metrics with high dependency on the distribution of the most common taxa were particularly robust. Simulated data showed sensitivity of results to the abundance distribution, confirming that data sets of high evenness and/or the application of metrics that are strongly affected by rare species are particularly sensitive to undersampling. The class of beta measure to be used should depend on the research question being asked as different metrics can lead to quite different conclusions even without undersampling effects. For each class of metric, there is a trade-off between robustness to undersampling and sensitivity to rare species. In consequence, using incidence-based metrics carries a particular risk of false conclusions when undersampled data are involved. Developing bias corrections for such metrics would be desirable.
Saturated hydraulic conductivity (K-s) is an important soil characteristic affecting soil water storage, runoff generation and erosion processes. In some areas where high-intensity rainfall coincides with low K-s values at shallow soil depths, frequent overland flow entails dense drainage networks. Consequently, linear structures such as flowlines alternate with inter-flowline areas. So far, investigations of the spatial variability of K-s mainly relied on isotropic covariance models which are unsuitable to reveal patterns resulting from linear structures. In the present study, we applied two sampling approaches so as to adequately characterize K-s spatial variability in a tropical forest catchment that features a high density of flowlines: A classical nested sampling survey and a purposive sampling strategy adapted to the presence of flowlines. The nested sampling approach revealed the dominance of small-scale variability, which is in line with previous findings. Our purposive sampling, however, detected a strong spatial gradient: surface K-s increased substantially as a function of distance to flowline; 10 m off flowlines, values were similar to the spatial mean of K-s. This deterministic trend can be included as a fixed effect in a linear mixed modeling framework to obtain realistic spatial fields of K-s. In a next step we used probability maps based on those fields and prevailing rainfall intensities to assess the hydrological relevance of the detected pattern. This approach suggests a particularly good agreement between the probability statements of K-s exceedance and observed overland flow occurrence during wet stages of the rainy season.
The Late Permian Zechstein Group in northeastern Germany is characterized by shelf and slope carbonates that rimmed a basin extending from eastern England through the Netherlands and Germany to Poland. Conventional reservoirs are found in grainstones rimming islands created by pre-existing paleohighs and platform-rimming shoals that compose steep margins in the north and ramp deposits in the southern part. The slope and basin deposits are characterized by debris flows and organic-rich mudstones. Lagoonal and basinal evaporites formed the seal for these carbonate and underlying sandstone reservoirs. The objective of this investigation is to evaluate potential unconventional reservoirs in organic-rich, fine-grained and/or tight mudrocks in slope and basin as well as platform carbonates occurring in this stratigraphic interval. Therefore, a comprehensive study was conducted that included sedimentology, sequence stratigraphy, petrography, and geochemistry. Sequence stratigraphic correlations from shelf to basin are crucial in establishing a framework that allows correlation of potential productive facies in fine-grained, organic-rich basinal siliceous and calcareous mudstones or interfingering tight carbonates and siltstones, ranging from the lagoon, to slope to basin, which might be candidates for forming an unconventional reservoir. Most organic-rich shales worldwide are associated with eustatic transgressions. The basal Zechstein cycles, Z1 and Z2, contain organic-rich siliceous and calcareous mudstones and carbonates that form major transgressive deposits in the basin. Maturities range from over-mature (gas) in the basin to oil-generation on the slope with variable TOC contents. This sequence stratigraphic and sedimentologic evaluation of the transgressive facies in the Z1 and Z2 assesses the potential for shale-gas/oil and hybrid unconventional plays. Potential unconventional reservoirs might be explored in laminated organic-rich mudstones within the oil window along the northern and southern slopes of the basin. Although the Zechstein Z1 and Z2 cycles might have limited shale-gas potential because of low thickness and deep burial depth to be economic at this point, unconventional reservoir opportunities that include hybrid and shale-oil potential are possible in the study area.
Detection of cancer precursors contributes to cancer prevention, for example, in the case of colorectal cancer. To record more patients early, ultrasensitive methods are required for the purpose of noninvasive precursor detection in body fluids. Our aim was to develop a method for enrichment and detection of known as well as unknown driver mutations in the Adenomatous polyposis coli (APC) gene. By coupled wild-type blocking (WTB) PCR and high-resolution melting (HRM), referred to as WTB-HRM, a minimum detection limit of 0.01% mutant in excess wild-type was achieved according to as little as 1 pg mutated DNA in the assay. The technique was applied to 80 tissue samples from patients with colorectal cancer (n = 17), adenomas (n = 50), serrated lesions (n = 8), and normal mucosa (n = 5). Any kind of known and unknown APC mutations (deletions, insertions, and base exchanges) being situated inside the mutation cluster region was distinguishable from wild-type DNA. Furthermore, by WTB-HRM, nearly twice as many carcinomas and 1.5 times more precursor lesions were identified to be mutated in APC, as compared with direct sequencing. By analyzing 31 associated stool DNA specimens all but one of the APC mutations could be recovered. Transferability of the WTB-HRM method to other genes was proven using the example of KRAS mutation analysis. In summary, WTB-HRM is a new approach for ultrasensitive detection of cancer-initiating mutations. In this sense, it appears especially applicable for noninvasive detection of colon cancer precursors in body fluids with excess wild-type DNA like stool. Cancer Prev Res; 6(9); 898-907. (C) 2013 AACR.
Irradiating a ferromagnet with a femtosecond laser pulse is known to induce an ultrafast demagnetization within a few hundred femtoseconds. Here we demonstrate that direct laser irradiation is in fact not essential for ultrafast demagnetization, and that electron cascades caused by hot electron currents accomplish it very efficiently. We optically excite a Au/Ni layered structure in which the 30 nm Au capping layer absorbs the incident laser pump pulse and subsequently use the X-ray magnetic circular dichroism technique to probe the femtosecond demagnetization of the adjacent 15 nm Ni layer. A demagnetization effect corresponding to the scenario in which the laser directly excites the Ni film is observed, but with a slight temporal delay. We explain this unexpected observation by means of the demagnetizing effect of a superdiffusive current of non-equilibrium, non-spin-polarized electrons generated in the Au layer.
Ultrafast soft X-ray emission spectroscopy of surface adsorbates using an X-ray free electron laser
(2013)
We report on an experimental system designed to probe chemical reactions on solid surfaces on a sub-picosecond timescale using soft X-ray emission spectroscopy at the Linac Coherent Light Source (LCLS) free electron laser (FEL) at the SLAC National Accelerator Laboratory. We analyzed the O 1s X-ray emission spectra recorded from atomic oxygen adsorbed on a Ru(0001) surface at a synchrotron beamline (SSRL, BL13-2) and an FEL beamline (LCLS, SXR). We have demonstrated conditions that provide negligible amount of FEL induced damage of the sample. In addition we show that the setup is capable of tracking the temporal evolution of electronic structure during a surface reaction of submonolayer quantities of CO molecules desorbing from the surface.
A diffractometer setup is presented, based on a laser-driven plasma X-ray source for reciprocal-space mapping with femtosecond temporal resolution. In order to map out the reciprocal space, an X-ray optic with a convergent beam is used with an X-ray area detector to detect symmetrically and asymmetrically diffracted X-ray photons simultaneously. The setup is particularly suited for measuring thin films or imperfect bulk samples with broad rocking curves. For quasi-perfect crystalline samples with insignificant in-plane Bragg peak broadening, the measured reciprocal-space maps can be corrected for the known resolution function of the diffractometer in order to achieve high-resolution rocking curves with improved data quality. In this case, the resolution of the diffractometer is not limited by the convergence of the incoming X-ray beam but is solely determined by its energy bandwidth.
Types of Body Shape
(2013)
TURBO2 - a MATLAB simulation to study the effects of bioturbation on paleoceanographic time series
(2013)
Bioturbation (or benthic mixing) causes significant distortions in marine stable isotope signals and other palaeoceanographic records. Although the influence of bioturbation on these records is well known it has rarely been dealt systematically. The MATLAB program called TURBO2 can be used to simulate the effect of bioturbation on individual sediment particles. It can therefore be used to model the distortion of all physical, chemical, and biological signals in deep-sea sediments, such as Mg/Ca ratios and UK37-based sea-surface temperature (SST) variations. In particular, it can be used to study the distortions in paleoceanographic records that are based on individual sediment particles, such as SST records based on foraminifera assemblages. Furthermore. TURBO2 provides a tool to study the effect of benthic mixing of isotope signals such as C-14, delta O-18, and delta C-13, measured in a stratigraphic carrier such as foraminifera shells.
Ag-TiO2 and Au-TiO2 hybrid electrodes were designed by covalent attachment of TiO2 nanoparticles to Ag or Au electrodes via an organic linker. The optical and electronic properties of these systems were investigated using the cytochrome b(5) (Cyt b(5)) domain of sulfite oxidase, exclusively attached to the TiO2 surface, as a Raman marker and model redox enzyme. Very strong SERR signals of Cyt b(5) were obtained for Ag-supported systems due to plasmonic field enhancement of Ag. Time-resolved surface-enhanced resonance Raman spectroscopic measurements yielded a remarkably fast electron transfer kinetic (k = 60 s(-1)) of Cyt b(5) to Ag. A much lower Raman intensity was observed for Au-supported systems with undefined and slow redox behavior. We explain this phenomenon on the basis of the different potential of zero charge of the two metals that largely influence the electronic properties of the TiO2 island film.
Transcriptome analysis through next-generation sequencing technologies allows the generation of detailed gene catalogs for non-model species, at the cost of new challenges with regards to computational requirements and bioinformatics expertise. Here, we present TRAPID, an online tool for the fast and efficient processing of assembled RNA-Seq transcriptome data, developed to mitigate these challenges. TRAPID offers high-throughput open reading frame detection, frameshift correction and includes a functional, comparative and phylogenetic toolbox, making use of 175 reference proteomes. Benchmarking and comparison against state-of-the-art transcript analysis tools reveals the efficiency and unique features of the TRAPID system.
Stochastic processes driven by stationary fractional Gaussian noise, that is, fractional Brownian motion and fractional Langevin-equation motion, are usually considered to be ergodic in the sense that, after an algebraic relaxation, time and ensemble averages of physical observables coincide. Recently it was demonstrated that fractional Brownian motion and fractional Langevin-equation motion under external confinement are transiently nonergodic-time and ensemble averages behave differently-from the moment when the particle starts to sense the confinement. Here we show that these processes also exhibit transient aging, that is, physical observables such as the time-averaged mean-squared displacement depend on the time lag between the initiation of the system at time t = 0 and the start of the measurement at the aging time t(a). In particular, it turns out that for fractional Langevin-equation motion the aging dependence on ta is different between the cases of free and confined motion. We obtain explicit analytical expressions for the aged moments of the particle position as well as the time-averaged mean-squared displacement and present a numerical analysis of this transient aging phenomenon.
The aim of the present study was to examine how different types of tracking—
between-school streaming, within-school streaming, and course-by-course
tracking—shape students’ mathematics self-concept. This was done in an
internationally comparative framework using data from the Programme for
International Student Assessment (PISA). After controlling for individual
and track mean achievement, results indicated that generally for students
in course-by-course tracking, high-track students had higher mathematics
self-concepts and low-track students had lower mathematics self-concepts.
For students in between-school and within-school streaming, the reverse pat-
tern was found. These findings suggest a solution to the ongoing debate about
the effects of tracking on students’ academic self-concept and suggest that the
reference groups to which students compare themselves differ according to the
type of tracking.
Cratons with their thick lithospheric roots can influence the thermal structure, and thus the convective flow, in the surrounding mantle. As mantle temperatures are hard to measure directly, depth variations in the mantle transition zone (MTZ) discontinuities are often employed as a proxy. Here, we use a large new data set of P-receiver functions to map the 410 km and 660 km discontinuities beneath the western edge of the East European Craton and adjacent Phanerozoic Europe across the most fundamental lithospheric boundary in Europe, the Trans-European Suture Zone (TESZ). We observe significantly shorter travel times for conversions from both MTZ discontinuities within the craton, caused by the high velocities of the cratonic root. By contrast, the differential travel time across the MTZ is normal to only slightly raised. This implies that any insulating effect of the cratonic keel does not reach the MTZ. In contrast to earlier observations in Siberia, we do not find any trace of a discontinuity at 520 km depth, which indicates a rather dry MTZ beneath the western edge of the craton. Within most of covered Phanerozoic Europe, the MTZ differential travel time is remarkably uniform and in agreement with standard Earth models. No widespread thermal effects of the various episodes of Caledonian and Variscan subduction that took place during the amalgamation of the continent remain. Only more recent tectonic events, related to Alpine subduction and Quarternary volcanism in the Eifel area, can be traced. While the East European craton shows no distinct imprint into the MTZ, we discover the signature of the TESZ in the MTZ in the form of a linear region of about 350 km width with a 1.5 s increase in differential travel time, which could either be caused by high water content or decreased temperature. Taking into account results of recent S-wave tomographies, raised water content in the MTZ cannot be the main cause for this observation. Accordingly, we explain the increase, equivalent to a 15 km thicker MTZ, by a temperature decrease of about 80 K. We discuss two alternative models for this temperature reduction, either a remnant of subduction or an indication of downwelling due to small-scale, edge-driven convection caused by the contrast in lithospheric thickness across the TESZ. Any subducted lithosphere found in the MTZ at this location is unlikely to be related to Variscan subduction along the TESZ, though, as Eurasia has moved significantly northward since the Variscan orogeny.
The generation of antibodies with designated specificity requires cost-intensive and time-consuming screening procedures. Here we present a new method by which hybridoma cells can be selected based on the specificity of the produced antibody by the use of antigen-toxin-conjugates thus eliminating the need of a screening procedure. Initial experiments were done with methotrexate as low molecular weight toxin and fluorescein as model antigen. Methotrexate and a methotrexate-fluorescein conjugate were characterized regarding their toxicity. Afterwards the effect of the fluorescein-specific antibody B13-DE1 on the toxicity of the methotrexate-fluorescein conjugate was determined. Finally, first results showed that hybridoma cells that produce fluorescein specific antibodies are able to grow in the presence of fluorescein-toxin-conjugates.
Algal tests have developed into routine tools for testing toxicity of pollutants in aquatic environments. Meanwhile, in addition to algal growth rates, an increasing number of fluorescence based methods are used for rapid and sensitive toxicity measures. The present study stresses the suitability of delayed fluorescence (DF) as a promising parameter for biotests. DF is based on the recombination fluorescence at the reaction centre of photosystem II, which is emitted only by photosynthetically active cells. We analyzed the effects of three chemicals (3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU), 3,5 Dichlorophenol (3,5 DCP) and copper) on the shape of the DF decay kinetics for potential use in phytoplankton toxicity tests. The short incubation tests were done with four phytoplankton species, with special emphasis on the cyanobacterium Microcystis aeruginosa. All species exhibited a high sensitivity to DCMU, but cyanobacteria were more affected by copper and less by 3,5 DCP than the tested green algae. Analyses of changes in the DF decay curve in response to the added chemicals indicated the feasibility of the DF decay approach as a rapid and sensitive testing tool.
Poststroke spasticity (PSS)-related disability is emerging as a significant health issue for stroke survivors. There is a need for predictors and early identification of PSS in order to minimize complications and maladaptation from spasticity. Reviewing the literature on stroke and upper motor neuron syndrome, spasticity, contracture, and increased muscle tone measured with the Modified Ashworth Scale and the Tone Assessment Scale provided data on the dynamic time course of PSS. Prevalence estimates of PSS were highly variable, ranging from 4% to 42.6%, with the prevalence of disabling spasticity ranging from 2% to 13%. Data on phases of the PSS continuum revealed evidence of PSS in 4% to 27% of those in the early time course (1-4 weeks poststroke), 19% to 26.7% of those in the postacute phase (1-3 months poststroke), and 17% to 42.6% of those in the chronic phase (>3 months poststroke). Data also identified key risk factors associated with the development of spasticity, including lower Barthel Index scores, severe degree of paresis, stroke-related pain, and sensory deficits. Although such indices could be regarded as predictors of PSS and thus enable early identification and treatment, the different measures of PSS used in those studies limit the strength of the findings. To optimize evaluation in the different phases of care, the best possible assessment of PSS would make use of a combination of indicators for clinical impairment, motor performance, activity level, quality of life, and patient-reported outcome measures. Applying these recommended measures, as well as increasing our knowledge of the physiologic predictors of PSS, will enable us to perform clinical and epidemiologic studies that will facilitate identification and early, multimodal treatment.
The task of expert finding is to rank the experts in the search space given a field of expertise as an input query. In this paper, we propose a topic modeling approach for this task. The proposed model uses latent Dirichlet allocation (LDA) to induce probabilistic topics. In the first step of our algorithm, the main topics of a document collection are extracted using LDA. The extracted topics present the connection between expert candidates and user queries. In the second step, the topics are used as a bridge to find the probability of selecting each candidate for a given query. The candidates are then ranked based on these probabilities. The experimental results on the Text REtrieval Conference (TREC) Enterprise track for 2005 and 2006 show that the proposed topic-based approach outperforms the state-of-the-art profile- and document-based models, which use information retrieval methods to rank experts. Moreover, we present the superiority of the proposed topic-based approach to the improved document-based expert finding systems, which consider additional information such as local context, candidate prior, and query expansion.
Silver nanoparticles (SNPs) are among the most commercialized nanoparticles because of their antibacterial effects. Besides being employed, e. g. as a coatingmaterial for sterile surfaces in household articles and appliances, the particles are also used in a broad range of medical applications. Their antibacterial properties make SNPs especially useful for wound disinfection or as a coating material for prostheses and surgical instruments. Because of their optical characteristics, the particles are of increasing interest in biodetection as well. Despite the widespread use of SNPs, there is little knowledge of their toxicity. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) and laser post-ionization secondary neutral mass spectrometry (Laser-SNMS) were used to investigate the effects of SNPs on human macrophages derived from THP-1 cells in vitro. For this purpose, macrophages were exposed to SNPs. The SNP concentration ranges were chosen with regard to functional impairments of the macrophages. To optimize the analysis of the macrophages, a special silicon wafer sandwich preparation technique was employed; ToF-SIMS was employed to characterize fragments originating from macrophage cell membranes. With the use of this optimized sample preparation method, the SNP-exposed macrophages were analyzed with ToF-SIMS and with Laser-SNMS. With Laser-SNMS, the three-dimensional distribution of SNPs in cells could be readily detected with very high efficiency, sensitivity, and submicron lateral resolution. We found an accumulation of SNPs directly beneath the cell membrane in a nanoparticular state as well as agglomerations of SNPs inside the cells.
Silver nanoparticles (SNP) are among the most commercialized nanoparticles. Here, we show that peptide-coated SNP cause functional impairment of human macrophages. A dose-dependent inhibition of phagocytosis is observed after nanoparticle treatment, and pretreatment of cells with N-acetyl cysteine (NAC) can counteract the phagocytosis disturbances caused by SNP.
Using the surface-sensitive mode of time-of-flight secondary ion mass spectrometry, in combination with multivariate statistical methods, we studied the composition of cell membranes in human macrophages upon exposure to SNP with and without NAC preconditioning. This method revealed characteristic changes in the lipid pattern of the cellular membrane outer leaflet in those cells challenged by SNP. Statistical analyses resulted in 19 characteristic ions, which can be used to distinguish between NAC pretreated and untreated macrophages. The present study discusses the assignments of surface cell membrane phospholipids for the identified ions and the resulting changes in the phospholipid pattern of treated cells. We conclude that the adverse effects in human macrophages caused by SNP can be partially reversed through NAC administration. Some alterations, however, remained.
Calcium (Ca2+) is a ubiquitous intracellular second messenger and involved in a plethora of cellular processes. Thus, quantification of the intracellular Ca2+ concentration ([Ca2+](i)) and of its dynamics is required for a comprehensive understanding of physiological processes and potential dysfunctions. A powerful approach for studying [Ca2+](i) is the use of fluorescent Ca2+ indicators. In addition to the fluorescence intensity as a common recording parameter, the fluorescence lifetime imaging microscopy (FLIM) technique provides access to the fluorescence decay time of the indicator dye. The nanosecond lifetime is mostly independent of variations in dye concentration, allowing more reliable quantification of ion concentrations in biological preparations. In this study, the feasibility of the fluorescent Ca2+ indicator Oregon Green Bapta-1 (OGB-1) for two-photon fluorescence lifetime imaging microscopy (2P-FLIM) was evaluated. In aqueous solution, OGB-1 displayed a Ca2+-dependent biexponential fluorescence decay behaviour, indicating the presence of a Ca2+-free and Ca2+-bound dye form. After sufficient dye loading into living cells, an in situ calibration procedure has also unravelled the Ca2+-free and Ca2+-bound dye forms from a global biexponential fluorescence decay analysis, although the dye's Ca2+ sensitivity is reduced. Nevertheless, quantitative [Ca2+](i) recordings and its stimulus-induced changes in salivary gland cells could be performed successfully. These results suggest that OGB-1 is suitable for 2P-FLIM measurements, which can gain access to cellular physiology.
Dynamics in materials typically involve different degrees of freedom, like charge, lattice, orbital and spin in a complex interplay. Time-resolved resonant inelastic X-ray scattering (RIXS) as a highly selective tool can provide unique insight and follow the details of dynamical processes while resolving symmetries, chemical and charge states, momenta, spin configurations, etc. In this paper, we review examples where the intrinsic scattering duration time is used to study femtosecond phenomena. Free-electron lasers access timescales starting in the sub-ps range through pump-probe methods and synchrotrons study the time scales longer than tens of ps. In these examples, time-resolved resonant inelastic X-ray scattering is applied to solids as well as molecular systems.
The geothermal potential in Tarutung is controlled by both the Sumatra Fault system and young arc volcanism. In this study we use the spatial distribution of seismic attenuation, calculated from local earthquake recordings, to image the 3-D seismic attenuation of the area and relate it with the temperature anomalies and the fluid distribution of the subsurface. A temporary seismic network of 42 stations was deployed around Tarutung and Sarulla (south of Tarutung) for a period of 10 months starting in 2011 May. Within this period, the network recorded 2586 local events. A high-quality subset of 229 events recorded by at least 10 stations was used for the attenuation inversion (tomography). Path-average attenuation (t(p)*) was calculated by using a spectral inversion method. The spread function, the contour lines of the model resolution matrix and the recovery test results show that our 3-D attenuation model (Q(p)) has good resolution around the Tarutung Basin and along the Sarulla graben. High attenuation (low Q(p)) related to the geothermal system is found in the northeast of the Tarutung Basin suggesting fluid pathways from below the Sumatra Fault. The upper part of the studied geothermal system in the Tarutung district seems to be mainly controlled by the fault structure rather than by magmatic activities. In the southwest of the Tarutung Basin, the high attenuation zone is associated with the Martimbang volcano. In the Sarulla region, a low-Q(p) anomaly is found along the graben within the vicinity of the Hopong caldera.
A problem encountered by many distributed hydrological modelling studies is high simulation errors at interior gauges when the model is only globally calibrated at the outlet. We simulated river runoff in the Elbe River basin in central Europe (148 268 km(2)) with the semi-distributed eco-hydrological model SWIM (Soil and Water Integrated Model). While global parameter optimisation led to Nash-Sutcliffe efficiencies of 0.9 at the main outlet gauge, comparisons with measured runoff series at interior points revealed large deviations. Therefore, we compared three different strategies for deriving sub-basin evapotranspiration: (1) modelled by SWIM without any spatial calibration, (2) derived from remotely sensed surface temperatures, and (3) calculated from long-term precipitation and discharge data. The results show certain consistencies between the modelled and the remote sensing based evapotranspiration rates, but there seems to be no correlation between remote sensing and water balance based estimations. Subsequent analyses for single sub-basins identify amongst others input weather data and systematic error amplification in inter-gauge discharge calculations as sources of uncertainty. The results encourage careful utilisation of different data sources for enhancements in distributed hydrological modelling.
Basement-cored ranges formed by reverse faulting within intracontinental mountain belts are often composed of poly-deformed lithologies. Geological data capable of constraining the timing, magnitude, and distribution of the most recent deformational phase are usually missing in such ranges. In this paper, we present new low temperature thermochronological and geological data from a transect through the basement-cored Terskey Range, located in the Kyrgyz Tien Shan. Using these data, we are able to investigate the range's late Cenozoic deformation for the first time. Displacements on reactivated faults are constrained and deformation of thermochronologically derived structural markers is assessed. These structural markers postdate the earlier deformational phases, providing the only record of Cenozoic deformation and of the reactivation of structures within the Terskey Range. Overall, these structural markers have a southern inclination, interpreted to reflect the decreasing inclination of the reverse fault bounding the Terskey Range. Our thermochronological data are also used to investigate spatial and temporal variations in the exhumation of the Terskey Range, identifying a three-stage Cenozoic exhumation history: (1) virtually no exhumation in the Paleogene, (2) increase to slightly higher exhumation rates at similar to 26-20Ma, and (3) significant increase in exhumation starting at similar to 10Ma.
In the Western Alps, the Piemont-Ligurian oceanic domain records blueschist to eclogite metamorphic conditions during the Alpine orogeny. This domain is classically divided into two "zones" (Combin and Zermatt-Saas), with contrasting metamorphic evolution, and separated tectonically by the Combin fault. This study presents new metamorphic and temperature (RSCM thermometry) data obtained in Piemont-Ligurian metasediments and proposes a reevaluation of the P-T evolution of this domain. In the upper unit (or "Combin zone") temperatures are in the range of 420-530 A degrees C, with an increase of temperature from upper to lower structural levels. Petrological evidences show that these temperatures are related to the retrograde path and to deformation at greenschist metamorphic conditions. This highlights heating during exhumation of HP metamorphic rocks. In the lower unit (or "Zermatt-Saas zone"), temperatures are very homogeneous in the range of 500-540 A degrees C. This shows almost continuous downward temperature increase in the Piemont-Ligurian domain. The observed thermal structure is interpreted as the result of the upper and lower unit juxtaposition along shear zones at a temperature of similar to 500 A degrees C during the Middle Eocene. This juxtaposition probably occurred at shallow crustal levels (similar to 15-20 km) within a subduction channel. We finally propose that the Piemont-Ligurian Domain should not be viewed as two distinct "zones", but rather as a stack of several tectonic slices.
This study presents the theory, applicability, and merits of the new THERIAK_D add-on for the open source Theriak/Domino software package. The add-on works as an interface between Theriak and user-generated scripts, providing the opportunity to process phase equilibrium computation parameters in a programming environment (e. g., C or MATLABV (R)). THERIAK_D supports a wide range of features such as calculating the solid rock density or testing the stability of mineral phases along any pressure-temperature (P-T) path and P-T grid. To demonstrate applicability, an example is given in which the solid rock density of a 2-D-temperature-pressure field is calculated, portraying a simplified subduction zone. Consequently, the add-on effectively combines thermodynamics and geodynamic modeling. The carefully documented examples could be easily adapted for a broad range of applications. THERIAK_D is free, and the program, user manual, and source codes may be downloaded from http://www.min.unikiel.de/similar to ed/theriakd/.
We obtained four pointings of over 100 ks each of the well-studied Wolf-Rayet star WR 6 with the XMM-Newton satellite. With a first paper emphasizing the results of spectral analysis, this follow-up highlights the X-ray variability clearly detected in all four pointings. However, phased light curves fail to confirm obvious cyclic behavior on the well-established 3.766 day period widely found at longer wavelengths. The data are of such quality that we were able to conduct a search for event clustering in the arrival times of X-ray photons. However, we fail to detect any such clustering. One possibility is that X-rays are generated in a stationary shock structure. In this context we favor a corotating interaction region (CIR) and present a phenomenological model for X-rays from a CIR structure. We show that a CIR has the potential to account simultaneously for the X-ray variability and constraints provided by the spectral analysis. Ultimately, the viability of the CIR model will require both intermittent long-term X-ray monitoring of WR 6 and better physical models of CIR X-ray production at large radii in stellar winds.
The voice of the other : heterotopy and heterology inBernard-Marie Koltes black battles with dogs
(2013)
Context. The Tarantula Nebula (a.k.a. 30 Dor) is a spectacular star-forming region in the Large Magellanic Cloud (LMC), seen through gas in the Galactic disc and halo. Diffuse interstellar bands (DIBs) offer a unique probe of the diffuse, cool-warm gas in these regions.
Aims. The aim is to use DIBs as diagnostics of the local interstellar conditions, whilst at the same time deriving properties of the yet-unknown carriers of these enigmatic spectral features.
Methods. Spectra of over 800 early-type stars from the Very Large Telescope Flames Tarantula Survey (VFTS) were analysed. Maps were created, separately, for the Galactic and LMC absorption in the DIBs at 4428 and 6614 angstrom and - in a smaller region near the central cluster R 136 - neutral sodium (the Na ID doublet); we also measured the DIBs at 5780 and 5797 angstrom.
Results. The maps show strong 4428 and 6614 angstrom DIBs in the quiescent cloud complex to the south of 30 Dor but weak absorption in the harsher environments to the north (bubbles) and near the OB associations. The Na maps show at least five kinematic components in the LMC and a shell-like structure surrounding R 136, and small-scale structure in the Milky Way. The strengths of the 4428, 5780, 5797 and 6614 angstrom DIBs are correlated, also with Na absorption and visual extinction. The strong 4428 angstrom DIB is present already at low Na column density but the 6614, 5780 and 5797 angstrom DIBs start to be detectable at subsequently larger Na column densities.
Conclusions. The carriers of the 4428, 6614, 5780 and 5797 angstrom DIBs are increasingly prone to removal from irradiated gas. The relative strength of the 5780 and 5797 angstrom DIBs clearly confirm the Tarantula Nebula as well as Galactic high-latitude gas to represent a harsh radiation environment. The resilience of the 4428 angstrom DIB suggests its carrier is large, compact and neutral. Structure is detected in the distribution of cool-warm gas on scales between one and > 100 pc in the LMC and as little as 0.01 pc in the Sun's vicinity. Stellar winds from the central cluster R 136 have created an expanding shell; some infalling gas is also detected, reminiscent of a galactic "fountain".
Context. Absorption-line systems detected in quasar spectra can be used to compare the value of the fine-structure constant, alpha, measured today on Earth with its value in distant galaxies. In recent years, some evidence has emerged of small temporal and also spatial variations in alpha on cosmological scales. These variations may reach a fractional level of approximate to 10 ppm (parts per million).
Aims. To test these claims we are conducting a Large Program of observations with the Very Large Telescope's Ultraviolet and Visual Echelle Spectrograph (UVES), and are obtaining high-resolution (R approximate to 60 000) and high signal-to-noise ratio (S/N approximate to 100) UVES spectra calibrated specifically for this purpose. Here we analyse the first complete quasar spectrum from this programme, that of HE 2217-2818.
Methods. We applied the many multiplet method to measure alpha in five absorption systems towards this quasar: z(abs) = 0.7866, 0.9424, 1.5558, 1.6279, and 1.6919.
Results. The most precise result is obtained for the absorber at z(abs) = 1.6919 where 3 Fe II transitions and Al II lambda 1670 have high S/N and provide a wide range of sensitivities to alpha. The absorption profile is complex with several very narrow features, and it requires 32 velocity components to be fitted to the data. We also conducted a range of tests to estimate the systematic error budget. Our final result for the relative variation in alpha in this system is Delta alpha/alpha = +1.3 +/- 2.4(stat) +/- 1.0(sys) ppm. This is one of the tightest current bounds on alpha-variation from an individual absorber. A second, separate approach to the data reduction, calibration, and analysis of this system yielded a slightly different result of -3.8 +/- 2.1(stat) ppm, possibly suggesting a larger systematic error component than our tests indicated. This approach used an additional 3 Fe II transitions, parts of which were masked due to contamination by telluric features. Restricting this analysis to the Fe II transitions alone and using a modified absorption profile model gave a result that is consistent with the first approach, Delta alpha/alpha = +1.1 +/- 2.6(stat) ppm. The four other absorbers have simpler absorption profiles, with fewer and broader features, and offer transitions with a narrower range of sensitivities to alpha. They therefore provide looser bounds on Delta alpha/alpha at the greater than or similar to 10 ppm precision level.
Conclusions. The absorbers towards quasar HE 2217-2818 reveal no evidence of any variation in alpha at the 3-ppm precision level (1 sigma confidence). If the recently reported 10-ppm dipolar variation in alpha across the sky is correct, the expectation at this sky position is (3.2-5.4) +/- 1.7 ppm depending on dipole model used. Our constraint of Delta alpha/alpha = +1.3 +/- 2.4(stat) +/- 1.0(sys) ppm is not inconsistent with this expectation.
We present an accurate analysis of the H-2 absorption lines from the z(abs) similar to 2.4018 damped Ly alpha system towards HE 0027-1836 observed with the Very Large Telescope Ultraviolet and Visual Echelle Spectrograph (VLT/UVES) as a part of the European Southern Observatory Large Programme 'The UVES large programme for testing fundamental physics' to constrain the variation of proton-to-electron mass ratio, mu m(p)/m(e). We perform cross-correlation analysis between 19 individual exposures taken over three years and the combined spectrum to check the wavelength calibration stability. We notice the presence of a possible wavelength-dependent velocity drift especially in the data taken in 2012. We use available asteroids spectra taken with UVES close to our observations to confirm and quantify this effect. We consider single-and two-component Voigt profiles to model the observed H-2 absorption profiles. We use both linear regression analysis and Voigt profile fitting where Delta mu/mu is explicitly considered as an additional fitting parameter. The two-component model is marginally favoured by the statistical indicators and we get Delta mu/mu = -2.5 +/- 8.1(stat) +/- 6.2(sys) ppm. When we apply the correction to the wavelength-dependent velocity drift, we find Delta mu/mu = -7.6 +/- 8.1(stat) +/- 6.3(sys) ppm. It will be important to check the extent to which the velocity drift we notice in this study is present in UVES data used for previous Delta mu/mu measurements.
Syn-rift shallow-marine carbonates of Late Aptian to Early Albian age in the southern Maestrat Basin (E Spain) register the thickest Aptian sedimentary record of the basin, and one of the most complete carbonate successions of this age reported in the northern Tethyan margin. The host limestones (Benassal Formation) are partially replaced by dolostones providing a new case study of fault-controlled hydrothermal dolomitization. The syn-rift sediments filled a graben controlled by normal basement faults. The Benassal Fm was deposited in a carbonate ramp with scarce siliciclastic input. The lithofacies are mainly characterized by the presence of orbitolinid foraminifera, corals and rudist bivalves fauna. The succession is stacked in three transgressive-regressive sequences (T-R) bounded by surfaces with sequence stratigraphic significance. The third sequence, which is reported for the first time in the basin, is formed by fully marine lithofacies of Albian age and represents the marine equivalent to the continental deposits of the Escucha Fm in the rest of the basin. The dolomitization of the host rock is spatially associated with the basement faults, and thus is fault-controlled. The dolostone forms seismic-scale stratabound tabular geobodies that extend several kilometres away from the fault zones, mostly in the hanging wall blocks, and host Mississippi Valley Type (MVT) deposits. The dolostones preferentially replaced middle to inner ramp grain-dominated fades from the third T-R sequences consisting of bioclastic packestones and peloidal grainstones. Field and petrology data indicate that the replacement took place after early calcite cementation and compaction, most likely during the Late Cretaceous post-rift stage of the basin. The dolostone registers the typical hydrothermal paragenesis constituted by the host limestone replacement, dolomite cementation and sulfide MVT mineralization. The Aptian succession studied provides a stratigraphic framework that can be used for oil exploration in age-equivalent rocks, especially in the Valencia Trough, offshore Spain. Moreover, this new case study constitutes a world class outcrop analogue for similar partially stratabound, dolomitized limestone reservoirs worldwide. (c) 2013 Elsevier Ltd. All rights reserved.
We report findings from psycholinguistic experiments investigating the detailed timing of processing morphologically complex words by proficient adult second (L2) language learners of English in comparison to adult native (L1) speakers of English. The first study employed the masked priming technique to investigate -ed forms with a group of advanced Arabic-speaking learners of English. The results replicate previously found L1/L2 differences in morphological priming, even though in the present experiment an extra temporal delay was offered after the presentation of the prime words.
The second study examined the timing of constraints against inflected forms inside derived words in English using the eye-movement monitoring technique and an additional acceptability judgment task with highly advanced Dutch L2 learners of English in comparison to adult L1 English controls. Whilst offline the L2 learners performed native-like, the eye-movement data showed that their online processing was not affected by the morphological constraint against regular plurals inside derived words in the same way as in native speakers. Taken together, these findings indicate that L2 learners are not just slower than native speakers in processing morphologically complex words, but that the L2 comprehension system employs real-time grammatical analysis (in this case, morphological information) less than the L1 system.
We classify the existent Birkhoff-type theorems into four classes: first, in field theory, the theorem states the absence of helicity 0- and spin 0-parts of the gravitational field. Second, in relativistic astrophysics, it is the statement that the gravitational far-field of a spherically symmetric star carries, apart from its mass, no information about the star; therefore, a radially oscillating star has a static gravitational far-field. Third, in mathematical physics, Birkhoff's theorem reads: up to singular exceptions of measure zero, the spherically symmetric solutions of Einstein's vacuum field equation with can be expressed by the Schwarzschild metric; for , it is the Schwarzschild-de Sitter metric instead. Fourth, in differential geometry, any statement of the type: every member of a family of pseudo-Riemannian space-times has more isometries than expected from the original metric ansatz, carries the name Birkhoff-type theorem. Within the fourth of these classes we present some new results with further values of dimension and signature of the related spaces; including them are some counterexamples: families of space-times where no Birkhoff-type theorem is valid. These counterexamples further confirm the conjecture, that the Birkhoff-type theorems have their origin in the property, that the two eigenvalues of the Ricci tensor of 2-D pseudo-Riemannian spaces always coincide, a property not having an analogy in higher dimensions. Hence, Birkhoff-type theorems exist only for those physical situations which are reducible to 2-D.
We classify the existent Birkhoff-type theorems into four classes: First, in field theory, the theorem states the absence of helicity 0- and spin 0-parts of the gravitational field. Second, in relativistic astrophysics, it is the statement that the gravitational far-field of a spherically symmetric star carries, apart from its mass, no information about the star; therefore, a radially oscillating star has a static gravitational far-field. Third, in mathematical physics, Birkhoff's theorem reads: up to singular exceptions of measure zero, the spherically symmetric solutions of Einstein's vacuum field equation with Lambda = 0 can be expressed by the Schwarzschild metric; for Lambda unequal 0, it is the Schwarzschild-de Sitter metric instead. Fourth, in differential geometry, any statement of the type: every member of a family of pseudo-Riemannian space-times has more isometries than expected from the original metric ansatz, carries the name Birkhoff-type theorem. Within the fourth of these classes we present some new results with further values of dimension and signature of the related spaces; including them are some counterexamples: families of space-times where no Birkhoff-type theorem is valid. These counterexamples further confirm the conjecture, that the Birkhoff-type theorems have their origin in the property, that the two eigenvalues of the Ricci tensor of two- dimensional pseudo-Riemannian spaces always coincide, a property not having an analogy in higher dimensions. Hence, Birkhoff-type theorems exist only for those physical situations which are reducible to two dimensions.
The Brassicaceae, including Arabidopsis thaliana and Brassica crops, is unmatched among plants in its wealth of genomic and functional molecular data and has long served as a model for understanding gene, genome, and trait evolution. However, genome information from a phylogenetic outgroup that is essential for inferring directionality of evolutionary change has been lacking. We therefore sequenced the genome of the spider flower (Tarenaya hassleriana) from the Brassicaceae sister family, the Cleomaceae. By comparative analysis of the two lineages, we show that genome evolution following ancient polyploidy and gene duplication events affect reproductively important traits. We found an ancient genome triplication in Tarenaya (Th-alpha) that is independent of the Brassicaceae-specific duplication (At-alpha) and nested Brassica (Br-a) triplication. To showcase the potential of sister lineage genome analysis, we investigated the state of floral developmental genes and show Brassica retains twice as many floral MADS (for MINICHROMOSOME MAINTENANCE1, AGAMOUS, DEFICIENS and SERUM RESPONSE FACTOR) genes as Tarenaya that likely contribute to morphological diversity in Brassica. We also performed synteny analysis of gene families that confer self-incompatibility in Brassicaceae and found that the critical SERINE RECEPTOR KINASE receptor gene is derived from a lineage-specific tandem duplication. The T. hassleriana genome will facilitate future research toward elucidating the evolutionary history of Brassicaceae genomes.
The Escherichia coli L-cysteine desulfurase IscS mobilizes sulfur from L-cysteine for the synthesis of several biomolecules such as iron-sulfur (FeS) clusters, molybdopterin, thiamin, lipoic acid, biotin, and the thiolation of tRNAs. The sulfur transfer from IscS to various biomolecules is mediated by different interaction partners (e.g. TusA for thiomodification of tRNAs, IscU for FeS cluster biogenesis, and ThiI for thiamine biosynthesis/tRNA thiolation), which bind at different sites of IscS. Transcriptomic and proteomic studies of a Delta tusA strain showed that the expression of genes of the moaABCDE operon coding for proteins involved in molybdenum cofactor biosynthesis is increased under aerobic and anaerobic conditions. Additionally, under anaerobic conditions the expression of genes encoding hydrogenase 3 and several molybdoenzymes such as nitrate reductase were also increased. On the contrary, the activity of all molydoenzymes analyzed was significantly reduced in the Delta tusA mutant. Characterization of the Delta tusA strain under aerobic conditions showed an overall low molybdopterin content and an accumulation of cyclic pyranopterin monophosphate. Under anaerobic conditions the activity of nitrate reductase was reduced by only 50%, showing that TusA is not essential for molybdenum cofactor biosynthesis. We present a model in which we propose that the direction of sulfur transfer for each sulfur-containing biomolecule is regulated by the availability of the interaction partner of IscS. We propose that in the absence of TusA, more IscS is available for FeS cluster biosynthesis and that the overproduction of FeS clusters leads to a modified expression of several genes.
In this preparatory chapter, the tools of stochastic analysis needed for the investigation of the asymptotic behavior of the stochastic Chafee-Infante equation are provided. In the first place, this encompasses a recollection of basic facts about Lévy processes with values in Hilbert spaces. Playing the role of the additive noise processes perturbing the deterministic Chafee-Infante equation in the systems the stochastic dynamics of which will be our main interest, symmetric ?-stable Lévy processes are in the focus of our investigation (Sect. 3.1).
In this article we analyze several examples of the syntactic structure ansí un...(Eng. such a...) apparently calqued from the German expression so ein... that can be found in different Judeo-Spanish texts since the second half of 19th Century. Although the eldest examples appeared in Judeo-Spanish translations of German novels, published in Vienna – what suggests that they could be mere cases derived from a kind of translation too attached to the original –, we can also find more examples in Sephardic texts produced outside the German speaking area (Bosnia, Bulgaria, etc.), not being necessarily translations of a German original. Dealing with all these cases, we will try to trace (and explain) the spread of the ansí un syntactic structure in modern Judeo-Spanish prose.
SIRT6 is a NAD(+)-dependent deacetylase that modulates chromatin structure and safeguards genomic stability. Until now, SIRT6 has been assigned to the nucleus and only nuclear targets of SIRT6 are known. Here, we demonstrate that in response to stress, C. elegans SIR-2.4 and its mammalian orthologue SIRT6 localize to cytoplasmic stress granules, interact with various stress granule components and induce their assembly. Loss of SIRT6 or inhibition of its catalytic activity in mouse embryonic fibroblasts impairs stress granule formation and delays disassembly during recovery, whereas deficiency of SIR-2.4 diminishes maintenance of P granules and decreases survival of C. elegans under stress conditions. Our findings uncover a novel, evolutionary conserved function of SIRT6 in the maintenance of stress granules in response to stress.
Background Job-anxiety, as distinguished from trait-anxiety, is associated with long-term sickness absence. The prevalence of job-anxiety within a working population is not known. Identifying individuals who would benefit from intervention might be useful.
Aims To investigate job-anxiety in employees not undergoing treatment for mental health illness, firstly by assessing the level of job-anxiety and work-related avoidance tendencies in a working sample, and secondly by testing whether job-anxiety is distinguishable from trait-anxiety.
Methods Cross-sectional survey of a convenience sample obtained through personal contact distribution. Employees from different professional settings completed an anonymous questionnaire and provided information on their employment status. The State-Trait-Anxiety Inventory (STAI-T) was used to measure trait-anxiety and the Job-Anxiety-Scale (JAS) was used to assess job (state) anxiety.
Results There was a 69% response rate (240 responses); 188 responses were available for analysis of whom 62% were women. There were no employees with high trait-anxiety. Ten employees (5%) reported increased job-anxiety and of these nine employees reported high 'tendencies of avoidance and workplace absence'. Avoidance was most often accompanied by the comorbid job-anxieties 'job-related social anxiety', 'fear of changes at work' and 'fears of existence', 'anticipatory' and 'conditioned' job-anxiety and 'panic symptoms'.
Conclusions In this sample, self-reported job-anxiety appeared as a specific type of anxiety as opposed to trait-anxiety. In the workplace job-anxiety can present as job-avoidance and sickness absence and should be distinguished from trait-anxiety. In practice, employers and occupational health practitioners should be aware of those employees prone to sickness absence.
The sidi Mohamed peridotites (Edough Massif, NE Algeria) - evidence for an upper mantle origin
(2013)
The Hercynian Edough massif is the easternmost crystalline massif of the Algerian coast. It consists of two tectonically superposed units composed of micaschists, gneisses, and peridotite. This study concentrates on the small and isolated Sidi Mohamed peridotite outcrop area (0.03 km(2)). The Sidi Mohamed peridotite is composed mainly of harzburgites (Mg-rich olivine and orthopyroxene as major minerals). The Ni (2051-2920 ppm), Cr (2368-5514 ppm) and MgO (similar to 28-35 wt.%) whole-rock composition and the relative depletion in Nb make these harzburgites comparable to depleted peridotites related to a subduction zone. We suggest that the Sidi Mohamed ultramafic body was derived directly from the upper mantle and tectonically incorporated into the gneiss units of the Edough metamorphic core complex in a subduction environment.
The Sabzevar ophiolites mark the Neotethys suture in east-north-central Iran. The Sabzevar metamorphic rocks, as part of the Cretaceous Sabzevar ophiolitic complex, consist of blueschist, amphibolite and greenschist. The Sabzevar blueschists contain sodic amphibole, epidote, phengite, calcite +/- A omphacite +/- A quartz. The epidote amphibolite is composed of sodic-calcic amphibole, epidote, albite, phengite, quartz +/- A omphacite, ilmenite and titanite. The greenschist contains chlorite, plagioclase and pyrite, as main minerals. Thermobarometry of a blueschist yields a pressure of 13-15.5 kbar at temperatures of 420-500 A degrees C. Peak metamorphic temperature/depth ratios were low (similar to 12 A degrees C/km), consistent with metamorphism in a subduction zone. The presence of epidote in the blueschist shows that the rocks were metamorphosed entirely within the epidote stability field. Amphibole schist samples experienced pressures of 5-7 kbar and temperatures between 450 and 550 A degrees C. The presence of chlorite, actinolite, biotite and titanite indicate greenschist facies metamorphism. Chlorite, albite and biotite replacing garnet or glaucophane suggests temperatures of > 300 A degrees C for greenschist facies. The formation of high-pressure metamorphic rocks is related to north-east-dipping subduction of the Neotethys oceanic crust and subsequent closure during lower Eocene between the Central Iranian Micro-continent and Eurasia (North Iran).
Soil moisture dynamics are affected by complex interactions among several factors. Understanding the relative importance of these factors is still an important challenge in the study of water fluxes and solute transport in unsaturated media. In this study, the spatio-temporal variability of surface soil moisture was investigated in a 10 ha flat cropped field located in northern Italy. Soil moisture was measured on a regular 50 x 50 m grid on seven dates during the growing season. For each measurement campaign, the spatial variability of the soil moisture was compared with the spatial variability of the soil texture and crop properties. In particular, to better understand the role of the vegetation, the spatio-temporal variability of two different parameters - leaf area index and crop height - was monitored on eight dates at different crop development stages. Statistical and geostatistical analysis was then applied to explore the interactions between these variables. In agreement with other studies, the results show that the soil moisture variability changes according to the average value within the field, with the standard deviation reaching a maximum value under intermediate mean soil moisture conditions and the coefficient of variation decreasing exponentially with increasing mean soil moisture. The controls of soil moisture variability change according to the average soil moisture within the field. Under wet conditions, the spatial distribution of the soil moisture reflects the variability of the soil texture. Under dry conditions, the spatial distribution of the soil moisture is affected mostly by the spatial variability of the vegetation. The interaction between these two factors is more important under intermediate soil moisture conditions. These results confirm the importance of considering the average soil moisture conditions within a field when investigating the controls affecting the spatial variability of soil moisture. This study highlights the importance of considering the spatio-temporal variability of the vegetation in investigating soil moisture dynamics, especially under intermediate and dry soil moisture conditions. The results of this study have important implications in different hydrological applications, such as for sampling design, ranking stability application, indirect measurements of soil properties and model parameterisation.
The traditional purpose of algorithm in education is to prepare students for programming. In our effort to introduce the practically missing computing science into Czech general secondary education, we have revisited this purpose.We propose an approach, which is in better accordance with the goals of general secondary education in Czechia. The importance of programming is diminishing, while recognition of algorithmic procedures and precise (yet concise) communication of algorithms is gaining importance. This includes expressing algorithms in natural language, which is more useful for most of the students than programming. We propose criteria to evaluate such descriptions. Finally, an idea about the limitations is required (inefficient algorithms, unsolvable problems, Turing’s test). We describe these adjusted educational goals and an outline of the resulting course. Our experience with carrying out the proposed intentions is satisfactory, although we did not accomplish all the defined goals.
The Respiratory Arsenite Oxidase: Structure and the Role of Residues
Surrounding the Rieske Cluster
(2013)
The arsenite oxidase (Aio) from the facultative autotrophic Alphaproteobacterium Rhizobium sp. NT-26 is a bioenergetic enzyme involved in the oxidation of arsenite to arsenate. The enzyme from the distantly related heterotroph, Alcaligenes faecalis, which is thought to oxidise arsenite for detoxification, consists of a large alpha subunit (AioA) with bis-molybdopterin guanine dinucleotide at its active site and a 3Fe-4S cluster, and a small beta subunit (AioB) which contains a Rieske 2Fe-2S cluster. The successful heterologous expression of the NT-26 Aio in Escherichia coli has resulted in the solution of its crystal structure. The NT-26 Aio, a heterotetramer, shares high overall similarity to the heterodimeric arsenite oxidase from A. faecalis but there are striking differences in the structure surrounding the Rieske 2Fe-2S cluster which we demonstrate explains the difference in the observed redox potentials (+225 mV vs. +130/160 mV, respectively). A combination of site-directed mutagenesis and electron paramagnetic resonance was used to explore the differences observed in the structure and redox properties of the Rieske cluster. In the NT-26 AioB the substitution of a serine (S126 in NT-26) for a threonine as in the A. faecalis AioB explains a -20 mV decrease in redox potential. The disulphide bridge in the A. faecalis AioB which is conserved in other betaproteobacterial AioB subunits and the Rieske subunit of the cytochrome bc(1) complex is absent in the NT-26 AioB subunit. The introduction of a disulphide bridge had no effect on Aio activity or protein stability but resulted in a decrease in the redox potential of the cluster. These results are in conflict with previous data on the betaproteobacterial AioB subunit and the Rieske of the bc(1) complex where removal of the disulphide bridge had no effect on the redox potential of the former but a decrease in cluster stability was observed in the latter.
Badlands have long been considered as model landscapes due to their perceived close relationship between form and process. The often intense features of erosion have also attracted many geomorphologists because the associated high rates of erosion appeared to offer the opportunity for studying surface processes and the resulting forms. Recently, the perceived simplicity of badlands has been questioned because the expected relationships between driving forces for erosion and the resulting sediment yield could not be observed. Further, a high variability in erosion and sediment yield has been observed across scales. Finally, denudation based on currently observed erosion rates would have lead to the destruction of most badlands a long time ago. While the perceived simplicity of badlands has sparked a disproportional (compared to the land surface they cover) amount of research, our increasing amount of information has not necessarily increased our understanding of badlands in equal terms. Overall, badlands appear to be more complex than initially assumed. In this paper, we review 40 years of research in the Zin Valley Badlands in Israel to reconcile some of the conflicting results observed there and develop a perspective on the function of badlands as model landscapes. While the data collected in the Zin Valley clearly confirm that spatial and temporal patterns of geomorphic processes and their interaction with topography and surface properties have to be understood, we still conclude that the process of realizing complexity in the "simple" badlands has a model function both for our understanding as well as perspective on all landscape systems.
In order to speed up Precise Point Positioning (PPP)'s convergence, a combined PPP method with GPS and GLONASS which is based on using raw observations is proposed, and the positioning results and convergence time have been compared with that of single system. The ionospheric delays and receiver's Differential Code Bias (DCB) corrections are estimated as unknown parameters in this method. The numerical results show that the combined PPP has not caused significant impacts on the final solutions, but it greatly improved Position Dilution of Precision (PDOP) and convergence speed and enhanced the reliability of the solution. Meanwhile, the convergence speed is greatly influenced by the receiver's DCB, positioning results in horizontal which are better than 10 cm can be realized within 10 min. In addition, the ionosphere and DCB products can be provided with high precision.
The PRO-wh connection in modal existential wh-constructions an argument in favor of semantic control
(2013)
Recent discussion of obligatory control in the literature mostly concentrates on the issue of which syntactic module (movement, agreement, etc.) is responsible for the establishment of the control relation. This paper looks at the issue of control from a higher order perspective. Abandoning the presupposition that control constituents denote propositions and that, therefore, control must be syntactic, I deliver an argument in favor of the property-type analysis of control constituents and, by transitivity, for a semantic resolution of the control relation. The argument comes from modal existential wh-constructions and in particular from a strong parallelism between obligatorily controlled PRO and wh-expressions. It is revealed that PRO and wh-words form a natural class, to the exclusion of all other types of nominal expressions. This is then turned into an argument of treating PRO (and wh-words) essentially as a logical lambda-operator, naturally leading to the property theory of control. In addition, the article contributes to our understanding of the syntax, semantics, and typology of modal existential wh-constructions. It is argued that at least one type of these constructions, what I call "control MECs", is embedded (minimally) by a complex predicate BE+FOR which expresses the state of availability (BE) which makes it possible for someone to profit (FOR) from the event characterized by the modal existential wh-construction.
Due to limited public budgets and the need to economize, the analysis of costs of hazard mitigation and emergency management of natural hazards becomes increasingly important for public natural hazard and risk management. In recent years there has been a growing body of literature on the estimation of losses which supported to help to determine benefits of measures in terms of prevented losses. On the contrary, the costs of mitigation are hardly addressed. This paper thus aims to shed some light on expenses for mitigation and emergency services. For this, we analysed the annual costs of mitigation efforts in four regions/countries of the Alpine Arc: Bavaria (Germany), Tyrol (Austria), South Tyrol (Italy) and Switzerland. On the basis of PPP values (purchasing power parities), annual expenses on public safety ranged from EUR 44 per capita in the Free State of Bavaria to EUR 216 in the Autonomous Province of South Tyrol. To analyse the (variable) costs for emergency services in case of an event, we used detailed data from the 2005 floods in the Federal State of Tyrol (Austria) as well as aggregated data from the 2002 floods in Germany. The analysis revealed that multi-hazards, the occurrence and intermixture of different natural hazard processes, contribute to increasing emergency costs. Based on these findings, research gaps and recommendations for costing Alpine natural hazards are discussed.
This study examined the unique contributions of various predictors to reading comprehension measured either without or with access to the text during testing. Reasoning ability, prior knowledge, and decoding skills were assumed to have stronger contributions to comprehension without text access than with text access, whereas current motivation should be more strongly associated with comprehension measured with access to the text. Metacognitive strategy knowledge and test anxiety were expected to be equally associated with comprehension in the two test conditions. Participants were 424 eighth- and ninth-grade students. They were presented with several instruments measuring cognitive and motivational predictors and read a text on a mathematical topic; then half of them took a test on comprehension either without or with text access. Based on multiple-group structural equation modeling, results indicated that reasoning ability, decoding ability, and metacognitive strategy knowledge significantly predicted comprehension only in the without-text condition, whereas achievement motivation and test anxiety significantly predicted comprehension only in the with-text condition. The unique contributions of intrinsic motivation to comprehension were significant, but did unexpectedly not differ between the without-text and the with-text condition.
The formate dehydrogenase from Rhodobactercapsulatus (RcFDH) is an oxygen-tolerant protein with an ()(2) subunit composition that is localized in the cytoplasm. It belongs to the group of metal and NAD(+)-dependent FDHs with the coordination of a molybdenum cofactor, four [Fe4S4] clusters and one [Fe2S2] cluster associated with the -subunit, one [Fe4S4] cluster and one FMN bound to the -subunit, and one [Fe2S2] cluster bound to the -subunit. RcFDH was heterologously expressed in Escherichiacoli and characterized. Cofactor analysis showed that the bis-molybdopterin guanine dinucleotide cofactor is bound to the FdsA subunit containing a cysteine ligand at the active site. A turnover rate of 2189min(-1) with formate as substrate was determined. The back reaction for the reduction of CO2 was catalyzed with a k(cat) of 89min(-1). The preference for formate oxidation shows an energy barrier for CO2 reduction of the enzyme. Furthermore, the FMN-containing and [Fe4S4]-containing -subunit together with the [Fe2S2]-containing -subunit forms a diaphorase unit with activities for both NAD(+) reduction and NADH oxidation. In addition to the structural genes fdsG, fdsB, and fdsA, the fds operon in R.capsulatus contains the fdsC and fdsD genes. Expression studies showed that RcFDH is only active when both FdsC and FdsD are present. Both proteins are proposed to be involved in bis-molybdopterin guanine dinucleotide modification and insertion into RcFDH.
The literature on performance information use explains how public managers deal with mainly quantitative data that are systematically collected and formally reported. This article argues that such a narrow understanding is incomplete, as it excludes all kinds of nonroutine performance information, including verbal, ad hoc, and qualitative feedback. To understand how responsive public managers are to performance feedback, alternative sources of performance information need to be taken into account. A literature review suggests considering two important sources of nonroutine feedback: organizational insiders and relevant external stakeholders. Using survey data from German local government, this article shows that public managers prefer to use nonroutine feedback over routine data from performance reports. Furthermore, a regression analysis indicates that different sources of performance information require different determinants to trigger their use. This finding is essential because it suggests that explanations of performance information use can covary with the information source studied.
Background: Dipeptidylpeptidase-4 inhibition is reported to have beneficial effects on myocardial ischemia. Mechanisms might include a reduced degradation of stromal cell-derived factor-1 alpha with subsequent increased recruitment of circulating stem cells and/or incretin receptor-dependent pathways. This study evaluated the novel xanthine-based dipeptidylpeptidase-4 inhibitors linagliptin (BI 1356) and BI 14361 in cardiac ischemia.
Methods: Male Wistar rats were pretreated with linagliptin or BI 14361 and subjected to ligation of the left anterior descending coronary artery for 30 min.
Results: Dipeptidylpeptidase-4 inhibition significantly reduced the infarct size after 7 days (-27.7%, p<0.05) and 8 weeks (-18.0%, p<0.05). There was a significantly improved maximum rate of left ventricular pressure decline (dP/dt min) in linagliptin-treated animals 8 weeks after ischemia/reperfusion. Apart from that, treatment did not improve cardiac function as determined by echocardiography and cardiac catheterization. Immunohistological staining revealed an increased number of cells positive for stromal cell-derived factor-1 alpha, CXCR-4 and CD34 within and around the infarcted area of BI 14361-treated animals.
Conclusions: Linagliptin and BI 14361 are able to reduce infarct size after myocardial ischemia. The immunohistological findings support the hypothesis that dipeptidylpeptidase-4 inhibition via reduced cleavage of stromal cell-derived factor-1 alpha might lead to an enhanced recruitment of CXCR-4+ circulating progenitor cells.
Japan launched the new Course of Study in April 2012, which has been carried out in elementary schools and junior high schools. It will also be implemented in senior high schools from April 2013. This article presents an overview of the information studies education in the new Course of Study for K-12. Besides, the authors point out what role experts of informatics and information studies education should play in the general education centered around information studies that is meant to help people of the nation to lead an active, powerful, and flexible life until the satisfying end.
The neonate nutrition hypothesis - early feeding affects the body stoichiometry of Daphnia offspring
(2013)
Aquatic herbivores consume variable quantities and qualities of food. In freshwater systems, where phosphorus (P) is often a primary limiting element, inadequate dietary P can slow maternal growth and reduce body P content. There remains uncertainty about whether and how dietary effects on mothers are transferred to offspring by way of egg provisioning. Using the keystone herbivore Daphnia, we tested a novel explanation (the neonate nutrition hypothesis') to determine whether the early nutrition of newborns affects their elemental composition and whether the indications of differences in maternal P nutrition found previously might be overestimated. We thus examined the P content of mothers and their eggs from deposition through development to the birth of neonates. We examined further whether very short periods of ingestion (3h) by the offspring alter the overall P content of juvenile Daphnia. We showed that strong dietary P effects on mothers were not directly transferred to their eggs. Irrespective of the supply of P in the maternal diet, the P content of eggs in different developmental stages and in (unfed) neonates did not differ. This indicates that Daphnia mothers do not reduce the quality (in terms of P) of newly produced offspring after intermittent periods (i.e. several days) of poor nutrition. In contrast, the P content of neonates reflected that of their food after brief periods of feeding, indicating that even temporary exposure to nutrient poor food immediately after birth may strongly affect the elemental composition of neonates. Our results thus support the neonate nutrition hypothesis, which, like differential maternal provisioning, is a possible explanation for the variable elemental quality of young Daphnia.
Global mean sea level has been steadily rising over the last century, is projected to increase by the end of this century, and will continue to rise beyond the year 2100 unless the current global mean temperature trend is reversed. Inertia in the climate and global carbon system, however, causes the global mean temperature to decline slowly even after greenhouse gas emissions have ceased, raising the question of how much sea-level commitment is expected for different levels of global mean temperature increase above preindustrial levels. Although sea-level rise over the last century has been dominated by ocean warming and loss of glaciers, the sensitivity suggested from records of past sea levels indicates important contributions should also be expected from the Greenland and Antarctic Ice Sheets. Uncertainties in the paleo-reconstructions, however, necessitate additional strategies to better constrain the sea-level commitment. Here we combine paleo-evidence with simulations from physical models to estimate the future sea-level commitment on a multimillennial time scale and compute associated regional sea-level patterns. Oceanic thermal expansion and the Antarctic Ice Sheet contribute quasi-linearly, with 0.4 m degrees C-1 and 1.2 m degrees C-1 of warming, respectively. The saturation of the contribution from glaciers is overcompensated by the nonlinear response of the Greenland Ice Sheet. As a consequence we are committed to a sea-level rise of approximately 2.3 m degrees C-1 within the next 2,000 y. Considering the lifetime of anthropogenic greenhouse gases, this imposes the need for fundamental adaptation strategies on multicentennial time scales.
We use archival UV absorption-line data from HST/STIS to statistically analyse the absorption characteristics of the high-velocity clouds (HVCs) in the Galactic halo towards more than 40 extragalactic background sources. We determine absorption covering fractions of low-and intermediate ions (Oi, Cii, Si ii, Mgii, Feii, Si iii, Civ, and Si iv) in the range f(c) = 0.20-0.70. For detailed analysis we concentrate on Si ii absorption components in HVCs, for which we investigate the distribution of column densities, b-values, and radial velocities. Combining information for Si ii and Mg II, and using a geometrical HVC model we investigate the contribution of HVCs to the absorption cross section of strong Mg ii absorbers in the local Universe. We estimate that the Galactic HVCs would contribute on average similar to 52 percent to the total strong Mg ii cross section of the Milky Way, if our Galaxy were to be observed from an exterior vantage point. We further estimate that the mean projected covering fraction of strong Mg ii absorption in the Milky Way halo and disc from an exterior vantage point is < f(c,sMgII)> = 0.31 for a halo radius of R = 61 kpc. These numbers, together with the observed number density of strong Mg ii absorbers at low redshift, indicate that the contribution of infalling gas clouds (i.e., HVC analogues) in the halos of Milky Way-type galaxies to the cross section of strong Mgii absorbers is < 34 percent. These findings are in line with the idea that outflowing gas (e. g., produced by galactic winds) in the halos of more actively star-forming galaxies dominate the absorption-cross section of strong Mgii absorbers in the local Universe.