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The investigation of luminal factors influencing zinc availability and accessibility in the intestine is of great interest when analyzing parameters regulating intestinal zinc resorption. Of note, intestinal mucins were suggested to play a beneficial role in the luminal availability of zinc. Their exact zinc binding properties, however, remain unknown and the impact of these glycoproteins on human intestinal zinc resorption has not been investigated in detail. Thus, the aim of this study is to elucidate the impact of intestinal mucins on luminal uptake of zinc into enterocytes and its transfer into the blood. In the present study, in vitro zinc binding properties of mucins were analyzed using commercially available porcine mucins and secreted mucins of the goblet cell line HT-29-MTX. The molecular zinc binding capacity and average zinc binding affinity of these glycoproteins demonstrates that mucins contain multiple zinc-binding sites with biologically relevant affinity within one mucin molecule. Zinc uptake into the enterocyte cell line Caco-2 was impaired by zinc-depleted mucins. Yet this does not represent their form in the intestinal lumen in vivo under zinc adequate conditions. In fact, zinc-uptake studies into enterocytes in the presence of mucins with differing degree of zinc saturation revealed zinc buffering by these glycoproteins, indicating that mucin-bound zinc is still available for the cells. Finally, the impact of mucins on zinc resorption using three-dimensional cultures was studied comparing the zinc transfer of a Caco-2/HT-29-MTX co-culture and conventional Caco-2 monoculture. Here, the mucin secreting co-cultures yielded higher fractional zinc resorption and elevated zinc transport rates, suggesting that intestinal mucins facilitate the zinc uptake into enterocytes and act as a zinc delivery system for the intestinal epithelium.
Local observations indicate that climate change and shifting disturbance regimes are causing permafrost degradation. However, the occurrence and distribution of permafrost region disturbances (PRDs) remain poorly resolved across the Arctic and Subarctic. Here we quantify the abundance and distribution of three primary PRDs using time-series analysis of 30-m resolution Landsat imagery from 1999 to 2014. Our dataset spans four continental-scale transects in North America and Eurasia, covering similar to 10% of the permafrost region. Lake area loss (-1.45%) dominated the study domain with enhanced losses occurring at the boundary between discontinuous and continuous permafrost regions. Fires were the most extensive PRD across boreal regions (6.59%), but in tundra regions (0.63%) limited to Alaska. Retrogressive thaw slumps were abundant but highly localized (< 10(-5)%). Our analysis synergizes the global-scale importance of PRDs. The findings highlight the need to include PRDs in next-generation land surface models to project the permafrost carbon feedback.
Allometric trophic network (ATN) models offer high flexibility and scalability while minimizing the number of parameters and have been successfully applied to investigate complex food web dynamics and their influence on food web diversity and stability. However, the realism of ATN model energetics has never been assessed in detail, despite their critical influence on dynamic biomass and production patterns. Here, we compare the energetics of the currently established original ATN model, considering only biomass-dependent basal respiration, to an extended ATN model version, considering both basal and assimilation-dependent activity respiration. The latter is crucial in particular for unicellular and invertebrate organisms which dominate the metabolism of pelagic and soil food webs. Based on metabolic scaling laws, we show that the extended ATN version reflects the energy transfer through a chain of four trophic levels of unicellular and invertebrate organisms more realistically than the original ATN version. Depending on the strength of top-down control, the original ATN model yields trophic transfer efficiencies up to 71% at either the third or the fourth trophic level, which considerably exceeds any realistic values. In contrast, the extended ATN version yields realistic trophic transfer efficiencies 30% at all trophic levels, in accordance with both physiological considerations and empirical evidence from pelagic systems. Our results imply that accounting for activity respiration is essential for consistently implementing the metabolic theory of ecology in ATN models and for improving their quantitative predictions, which makes them more powerful tools for investigating the dynamics of complex natural communities.
The primary function of leaves is to provide an interface between plants and their environment for gas exchange, light exposure and thermoregulation. Leaves have, therefore a central contribution to plant fitness by allowing an efficient absorption of sunlight energy through photosynthesis to ensure an optimal growth. Their final geometry will result from a balance between the need to maximize energy uptake while minimizing the damage caused by environmental stresses. This intimate relationship between leaf and its surroundings has led to an enormous diversification in leaf forms. Leaf shape varies between species, populations, individuals or even within identical genotypes when those are subjected to different environmental conditions. For instance, the extent of leaf margin dissection has, for long, been found to inversely correlate with the mean annual temperature, such that Paleobotanists have used models based on leaf shape to predict the paleoclimate from fossil flora. Leaf growth is not only dependent on temperature but is also regulated by many other environmental factors such as light quality and intensity or ambient humidity. This raises the question of how the different signals can be integrated at the molecular level and converted into clear developmental decisions. Several recent studies have started to shed the light on the molecular mechanisms that connect the environmental sensing with organ-growth and patterning. In this review, we discuss the current knowledge on the influence of different environmental signals on leaf size and shape, their integration as well as their importance for plant adaptation.
High-latitude treeless ecosystems represent spatially highly heterogeneous landscapes with small net carbon fluxes and a short growing season. Reliable observations and process understanding are critical for projections of the carbon balance of the climate-sensitive tundra. Space-borne remote sensing is the only tool to obtain spatially continuous and temporally resolved information on vegetation greenness and activity in remote circumpolar areas. However, confounding effects from persistent clouds, low sun elevation angles, numerous lakes, widespread surface inundation, and the sparseness of the vegetation render it highly challenging. Here, we conduct an extensive analysis of the timing of peak vegetation productivity as shown by satellite observations of complementary indicators of plant greenness and photosynthesis. We choose to focus on productivity during the peak of the growing season, as it importantly affects the total annual carbon uptake. The suite of indicators are as follows: (1) MODIS-based vegetation indices (VIs) as proxies for the fraction of incident photosynthetically active radiation (PAR) that is absorbed (fPAR), (2) VIs combined with estimates of PAR as a proxy of the total absorbed radiation (APAR), (3) sun-induced chlorophyll fluorescence (SIF) serving as a proxy for photosynthesis, (4) vegetation optical depth (VOD), indicative of total water content and (5) empirically upscaled modelled gross primary productivity (GPP). Averaged over the pan-Arctic we find a clear order of the annual peak as APAR <= GPP < SIF < VIs/VOD. SIF as an indicator of photosynthesis is maximised around the time of highest annual temperatures. The modelled GPP peaks at a similar time to APAR. The time lag of the annual peak between APAR and instantaneous SIF fluxes indicates that the SIF data do contain information on light-use efficiency of tundra vegetation, but further detailed studies are necessary to verify this. Delayed peak greenness compared to peak photosynthesis is consistently found across years and land-cover classes. A particularly late peak of the normalised difference vegetation index (NDVI) in regions with very small seasonality in greenness and a high amount of lakes probably originates from artefacts. Given the very short growing season in circumpolar areas, the average time difference in maximum annual photosynthetic activity and greenness or growth of 3 to 25 days (depending on the data sets chosen) is important and needs to be considered when using satellite observations as drivers in vegetation models.
We present an optically addressed non-pixelated spatial light modulator. The system is based on reversible photoalignment of a LC cell using a red light sensitive novel azobenzene photoalignment layer. It is an electrode-free device that manipulates the liquid crystal orientation and consequently the polarization via light without artifacts caused by electrodes. The capability to miniaturize the spatial light modulator allows the integration into a microscope objective. This includes a miniaturized 200 channel optical addressing system based on a VCSEL array and hybrid refractive-diffractive beam shapers. As an application example, the utilization as a microscope objective integrated analog phase contrast modulator is shown. (C) 2018 Optical Society of America under the terms of the OSA Open Access Publishing Agreement
Applications with different characteristics in the cloud may have different resources preferences. However, traditional resource allocation and scheduling strategies rarely take into account the characteristics of applications. Considering that an I/O-intensive application is a typical type of application and that frequent I/O accesses, especially small files randomly accessing the disk, may lead to an inefficient use of resources and reduce the quality of service (QoS) of applications, a weight allocation strategy is proposed based on the available resources that a physical server can provide as well as the characteristics of the applications. Using the weight obtained, a resource allocation and scheduling strategy is presented based on the specific application characteristics in the data center. Extensive experiments show that the strategy is correct and can guarantee a high concurrency of I/O per second (IOPS) in a cloud data center with high QoS. Additionally, the strategy can efficiently improve the utilization of the disk and resources of the data center without affecting the service quality of applications.
Currently, several large-scale ice-flow models impose a condition on ice flux across grounding lines using an analytically motivated parameterisation of grounding-line flux. It has been suggested that employing this analytical expression alleviates the need for highly resolved computational domains around grounding lines of marine ice sheets. While the analytical flux formula is expected to be accurate in an unbuttressed flow-line setting, its validity has hitherto not been assessed for complex and realistic geometries such as those of the Antarctic Ice Sheet. Here the accuracy of this analytical flux formula is tested against an optimised ice flow model that uses a highly resolved computational mesh around the Antarctic grounding lines. We find that when applied to the Antarctic Ice Sheet the analytical expression provides inaccurate estimates of ice fluxes for almost all grounding lines. Furthermore, in many instances direct application of the analytical formula gives rise to unphysical complex-valued ice fluxes. We conclude that grounding lines of the Antarctic Ice Sheet are, in general, too highly buttressed for the analytical parameterisation to be of practical value for the calculation of grounding-line fluxes.
Background Previous studies found evidence that dispositional optimism is related to lower pain sensitivity. Recent findings suggest that temporarily increasing optimism by means of imagining a positive future may also have pain-alleviating effects. Objectives The present experiment was designed to investigate conditioned pain modulation (CPM) as a potential underlying mechanism of this pain-alleviating effect of induced optimism. Methods For this purpose, 45 healthy participants were randomized into an optimistic or neutral imagery condition. Additionally, participants completed questionnaires on dispositional optimism, pain catastrophizing and pain expectations. CPM was assessed by delivering a series of five heat pain stimuli on the nondominant hand before and during immersion of the dominant hand in water of 5 degrees C for 70 s. Results A clear CPM effect was found, that is heat pain reports were lower during simultaneous cold water stimulation. Although the optimism manipulation successfully increased optimism, it did not affect pain ratings or CPM. Post hoc analyses indicated that dispositional optimism was not associated with the magnitude of CPM, but pain catastrophizing and pain expectations did significantly correlate with the CPM effect. Conclusion Pain-specific but not general cognitions appear to influence endogenous pain modulation. Significance Conditioned pain modulation is not the underlying mechanism of the pain-alleviating effects of induced optimism. However, pain-specific cognitions including pain catastrophizing and pain expectations affect endogenous pain modulation which should be taken into account in treatment and CPM research.
Environmental drivers interactively affect individual tree growth across temperate European forests
(2018)
Forecasting the growth of tree species to future environmental changes requires abetter understanding of its determinants. Tree growth is known to respond to global‐change drivers such as climate change or atmospheric deposition, as well as to localland‐use drivers such as forest management. Yet, large geographical scale studiesexamining interactive growth responses to multiple global‐change drivers are relativelyscarce and rarely consider management effects. Here, we assessed the interactiveeffects of three global‐change drivers (temperature, precipitation and nitrogen deposi-tion) on individual tree growth of three study species (Quercus robur/petraea, Fagus syl-vatica and Fraxinus excelsior). We sampled trees along spatial environmental gradientsacross Europe and accounted for the effects of management for Quercus. We collectedincrement cores from 267 trees distributed over 151 plots in 19 forest regions andcharacterized their neighbouring environment to take into account potentially confounding factors such as tree size, competition, soil conditions and elevation. Wedemonstrate that growth responds interactively to global‐change drivers, with species ‐specific sensitivities to the combined factors. Simultaneously high levels of precipita-tion and deposition benefited Fraxinus, but negatively affected Quercus’ growth, high-lighting species‐specific interactive tree growth responses to combined drivers. ForFagus, a stronger growth response to higher temperatures was found when precipita-tion was also higher, illustrating the potential negative effects of drought stress underwarming for this species. Furthermore, we show that past forest management canmodulate the effects of changing temperatures on Quercus’ growth; individuals in plotswith a coppicing history showed stronger growth responses to higher temperatures.Overall, our findings highlight how tree growth can be interactively determined by glo-bal‐change drivers, and how these growth responses might be modulated by past for-est management. By showing future growth changes for scenarios of environmentalchange, we stress the importance of considering multiple drivers, including past man-agement and their interactions, when predicting tree growth.
In a preferential looking paradigm, we studied how children's looking behavior and pupillary response were modulated by the degree of phonological mismatch between the correct label of a target referent and its manipulated form. We manipulated degree of mismatch by introducing one or more featural changes to the target label. Both looking behavior and pupillary response were sensitive to degree of mismatch, corroborating previous studies that found differential responses in one or the other measure. Using time-course analyses, we present for the first time results demonstrating full separability among conditions (detecting difference not only between one vs. more, but also between two and three featural changes). Furthermore, the correct labels and small featural changes were associated with stable target preference, while large featural changes were associated with oscillating looking behavior, suggesting significant shifts in looking preference over time. These findings further support and extend the notion that early words are represented in great detail, containing subphonemic information.
Geomagnetic indices are convenient quantities that distill the complicated physics of some region or aspect of near-Earth space into a single parameter. Most of the best-known indices are calculated from ground-based magnetometer data sets, such as Dst, SYM-H, Kp, AE, AL, and PC. Many models have been created that predict the values of these indices, often using solar wind measurements upstream from Earth as the input variables to the calculation. This document reviews the current state of models that predict geomagnetic indices and the methods used to assess their ability to reproduce the target index time series. These existing methods are synthesized into a baseline collection of metrics for benchmarking a new or updated geomagnetic index prediction model. These methods fall into two categories: (1) fit performance metrics such as root-mean-square error and mean absolute error that are applied to a time series comparison of model output and observations and (2) event detection performance metrics such as Heidke Skill Score and probability of detection that are derived from a contingency table that compares model and observation values exceeding (or not) a threshold value. A few examples of codes being used with this set of metrics are presented, and other aspects of metrics assessment best practices, limitations, and uncertainties are discussed, including several caveats to consider when using geomagnetic indices. Plain Language Summary One aspect of space weather is a magnetic signature across the surface of the Earth. The creation of this signal involves nonlinear interactions of electromagnetic forces on charged particles and can therefore be difficult to predict. The perturbations that space storms and other activity causes in some observation sets, however, are fairly regular in their pattern. Some of these measurements have been compiled together into a single value, a geomagnetic index. Several such indices exist, providing a global estimate of the activity in different parts of geospace. Models have been developed to predict the time series of these indices, and various statistical methods are used to assess their performance at reproducing the original index. Existing studies of geomagnetic indices, however, use different approaches to quantify the performance of the model. This document defines a standardized set of statistical analyses as a baseline set of comparison tools that are recommended to assess geomagnetic index prediction models. It also discusses best practices, limitations, uncertainties, and caveats to consider when conducting a model assessment.
The Gutenberg-Richter relation for earthquake magnitudes is the most famous empirical law in seismology. It states that the frequency of earthquake magnitudes follows an exponential distribution; this has been found to be a robust feature of seismicity above the completeness magnitude, and it is independent of whether global, regional, or local seismicity is analyzed. However, the exponent b of the distribution varies significantly in space and time, which is important for process understanding and seismic hazard assessment; this is particularly true because of the fact that the Gutenberg-Richter b-value acts as a proxy for the stress state and quantifies the ratio of large-to-small earthquakes. In our work, we focus on the automatic detection of statistically significant temporal changes of the b-value in seismicity data. In our approach, we use Bayes factors for model selection and estimate multiple change-points of the frequency-magnitude distribution in time. The method is first applied to synthetic data, showing its capability to detect change-points as function of the size of the sample and the b-value contrast. Finally, we apply this approach to examples of observational data sets for which b-value changes have previously been stated. Our analysis of foreshock and after-shock sequences related to mainshocks, as well as earthquake swarms, shows that only a portion of the b-value changes is statistically significant.
Several meta-analyses have been published summarizing the associations of the Mediterranean diet (MedDiet) with chronic diseases. We evaluated the quality and credibility of evidence from these meta-analyses as well as characterized the different indices used to define MedDiet and re-calculated the associations with the different indices identified. We conducted an umbrella review of meta-analyses on cohort studies evaluating the association of the MedDiet with type 2 diabetes, cardiovascular disease, cancer and cognitive-related diseases. We used the AMSTAR (A MeaSurement Tool to Assess systematic Reviews) checklist to evaluate the methodological quality of the meta-analyses, and the NutriGrade scoring system to evaluate the credibility of evidence. We also identified different indices used to define MedDiet; tests for subgroup differences were performed to compare the associations with the different indices when at least 2 studies were available for different definitions. Fourteen publications were identified and within them 27 meta-analyses which were based on 70 primary studies. Almost all meta-analyses reported inverse associations between MedDiet and risk of chronic disease, but the credibility of evidence was rated low to moderate. Moreover, substantial heterogeneity was observed on the use of the indices assessing adherence to the MedDiet, but two indices were the most used ones [Trichopoulou MedDiet (tMedDiet) and alternative MedDiet (aMedDiet)]. Overall, we observed little difference in risk associations comparing different MedDiet indices in the subgroup meta-analyses. Future prospective cohort studies are advised to use more homogenous definitions of the MedDiet to improve the comparability across meta-analyses.
Research question: This study aimed to establish reference values in 1-14 year old healthy children and to implement FPA-percentile curves for daily clinical use. Methods: 5910 healthy children performed at least 3 repetitions of barefoot walking over an instrumented walkway using a pressure measurement platform. The FPA [degrees] was extracted and analyzed by age and gender (mean +/- standard deviation; median with percentiles, MANOVA (age, gender) and Wilcoxon-Signed-Rank test for intra-individual side differences (alpha = 0.05). Results: FPA maximum was observed in 2-year-old children and diminished significant until the age of 4 to moderate out-toeing. For ages 5-14, no statistically significant differences in FPA values were present (p > 0.05). MANOVA confirmed age (p < 0.001) and gender (p < 0.001) as significant FPA influencing factors, without combined effect (p > 0.05). In every age group, right feet showed significantly greater out-toeing (p < 0.05). Significance: Percentile values indicate a wide FPA range in children. FPA development in young children shows a spontaneous shift towards moderate external rotation (age 2-4), whereby in-toeing <= 1-5 degrees can be present, but can return to normal. Bilateral in-toeing after the age of four and unilateral in-toeing after the age of seven should be monitored.
Tundra be dammed
(2018)
Increasing air temperatures are changing the arctic tundra biome. Permafrost is thawing, snow duration is decreasing, shrub vegetation is proliferating, and boreal wildlife is encroaching. Here we present evidence of the recent range expansion of North American beaver (Castor canadensis) into the Arctic, and consider how this ecosystem engineer might reshape the landscape, biodiversity, and ecosystem processes. We developed a remote sensing approach that maps formation and disappearance of ponds associated with beaver activity. Since 1999, 56 new beaver pond complexes were identified, indicating that beavers are colonizing a predominantly tundra region (18,293km(2)) of northwest Alaska. It is unclear how improved tundra stream habitat, population rebound following overtrapping for furs, or other factors are contributing to beaver range expansion. We discuss rates and likely routes of tundra beaver colonization, as well as effects on permafrost, stream ice regimes, and freshwater and riparian habitat. Beaver ponds and associated hydrologic changes are thawing permafrost. Pond formation increases winter water temperatures in the pond and downstream, likely creating new and more varied aquatic habitat, but specific biological implications are unknown. Beavers create dynamic wetlands and are agents of disturbance that may enhance ecosystem responses to warming in the Arctic.
Background Heart failure (HF) is a complex, chronic condition that is associated with debilitating symptoms, all of which necessitate close follow-up by health care providers. Lack of disease monitoring may result in increased mortality and more frequent hospital readmissions for decompensated HF. Remote patient management (RPM) in this patient population may help to detect early signs and symptoms of cardiac decompensation, thus enabling a prompt initiation of the appropriate treatment and care before a manifestation of HF decompensation. Objective The objective of the present article is to describe the design of a new trial investigating the impact of RPM on unplanned cardiovascular hospitalisations and mortality in HF patients. Methods The TIM-HF2 trial is designed as a prospective, randomised, controlled, parallel group, open (with randomisation concealment), multicentre trial with pragmatic elements introduced for data collection. Eligible patients with HF are randomised (1:1) to either RPM + usual care or to usual care only and are followed for 12 months. The primary outcome is the percentage of days lost due to unplanned cardiovascular hospitalisations or all-cause death. The main secondary outcomes are all-cause and cardiovascular mortality. Conclusion The TIM-HF2 trial will provide important prospective data on the potential beneficial effect of telemedical monitoring and RPM on unplanned cardiovascular hospitalisations and mortality in HF patients.
The plant pathogen Pseudomonas syringae is a gram-negative bacterium which infects a wide range of plant species including important crops plants. To suppress plant immunity and cause disease P.syringae injects type-III effector proteins (T3Es) into the plant cell cytosol. In this study, we identified a novel target of the well characterized bacterial T3E HopZ1a. HopZ1a is an acetyltransferase that was shown to disrupt vesicle transport during innate immunity by acetylating tubulin. Using a yeast-two-hybrid screen approach, we identified a REMORIN (REM) protein from tobacco as a novel HopZ1a target. HopZ1a interacts with REM at the plasma membrane (PM) as shown by split-YFP experiments. Interestingly, we found that PBS1, a well-known kinase involved in plant immunity also interacts with REM in pull-down assays, and at the PM as shown by BiFC. Furthermore, we confirmed that REM is phosphorylated by PBS1 in vitro. Overexpression of REM provokes the upregulation of defense genes and leads to disease-like phenotypes pointing to a role of REM in plant immune signaling. Further protein-protein interaction studies reveal novel REM binding partners with a possible role in plant immune signaling. Thus, REM might act as an assembly hub for an immune signaling complex targeted by HopZ1a. Taken together, this is the first report describing that a REM protein is targeted by a bacterial effector. How HopZ1a might mechanistically manipulate the plant immune system through interfering with REM function will be discussed.
Purpose Prolonged bed rest and microgravity in space cause intervertebral disc (IVD) degeneration. However, the underlying molecular mechanisms are not completely understood. Transient receptor potential canonical (TRPC) channels are implicated in mechanosensing of several tissues, but are poorly explored in IVDs. Methods Primary human IVD cells from surgical biopsies composed of both annulus fibrosus and nucleus pulposus (passage 1-2) were exposed to simulated microgravity and to the TRPC channel inhibitor SKF-96365 (SKF) for up to 5days. Proliferative capacity, cell cycle distribution, senescence and TRPC channel expression were analyzed. Results Both simulated microgravity and TRPC channel antagonism reduced the proliferative capacity of IVD cells and induced senescence. While significant changes in cell cycle distributions (reduction in G1 and accumulation in G2/M) were observed upon SKF treatment, the effect was small upon 3days of simulated microgravity. Finally, downregulation of TRPC6 was shown under simulated microgravity. Conclusions Simulated microgravity and TRPC channel inhibition both led to reduced proliferation and increased senescence. Furthermore, simulated microgravity reduced TRPC6 expression. IVD cell senescence and mechanotransduction may hence potentially be regulated by TRPC6 expression. This study thus reveals promising targets for future studies.
Introduction: The goal of the present study was to identify the prospective relations between weight/shape and muscularity concerns and emotional problems in adolescents. Methods: Self-report data of 966 German male and female adolescents were analyzed in a cross lagged panel design. Results: Analyses of latent means revealed significant correlations between weight/shape concern and emotional problems as well as between muscularity concern and emotional problems in both genders. Moreover, weight/shape concern predicted emotional problems prospectively, but only in girls. Regarding muscularity concern, we could not find any prospective relation with emotional problems In boys or girls from the general population. Conclusions: It is assumed that as appearance is highly relevant for the self-concept in girls, concerns about the look might promote emotional problems. Thus, weight/shape concern should be addressed in the prevention of emotional problems in adolescent girls, whereas further research is necessary investigating the contribution of muscularity concern in this context.
We perform a statistical study calculating electromagnetic ion cyclotron (EMIC) wave amplitudes based off in situ plasma measurements taken by the Van Allen Probes’ (1.1–5.8 Re) Helium, Oxygen, Proton, Electron (HOPE) instrument. Calculated wave amplitudes are compared to EMIC waves observed by the Electric and Magnetic Field Instrument Suite and Integrated Science on board the Van Allen Probes during the same period. The survey covers a 22-month period (1 November 2012 to 31 August 2014), a full Van Allen Probe magnetic local time (MLT) precession. The linear theory proxy was used to identify EMIC wave events with plasma conditions favorable for EMIC wave excitation. Two hundred and thirty-two EMIC wave events (103 H+-band and 129 He+-band) were selected for this comparison. Nearly all events selected are observed beyond L = 4. Results show that calculated wave amplitudes exclusively using the in situ HOPE measurements produce amplitudes too low compared to the observed EMIC wave amplitudes. Hot proton anisotropy (Ahp) distributions are asymmetric in MLT within the inner (L < 7) magnetosphere with peak (minimum) Ahp, ∼0.81 to 1.00 (∼0.62), observed in the dawn (dusk), 0000 < MLT ≤ 1200 (1200 < MLT ≤ 2400), sectors. Measurements of Ahp are found to decrease in the presence of EMIC wave activity. Ahp amplification factors are determined and vary with respect to EMIC wave-band and MLT. He+-band events generally require double (quadruple) the measured Ahp for the dawn (dusk) sector to reproduce the observed EMIC wave amplitudes.
Bedrock landsliding in mountain belts can elevate overall chemical weathering rates through rapid dissolution of exhumed reactive mineral phases in transiently stored deposits. This link between a key process of erosion and the resultant weathering affects the sequestering of carbon dioxide through weathering of silicate minerals and broader links between erosion in active orogens and climate change. Here we address the effect on the carbon cycle of weathering induced by bedrock landsliding in Taiwan and the Western Southern Alps of New Zealand. Using solute chemistry data from samples of seepage from landslide deposits and river discharge from catchments with variable proportions of landsliding, we model the proportion of silicate and carbonate weathering and the balance of sulfuric and carbonic acids that act as weathering agents. We correct for secondary precipitation, geothermal, and cyclic input, to find a closer approximation of the weathering explicitly occurring within landslide deposits. We find highly variable proportions of sulfuric and carbonic acids driving weathering in landslides and stable hillslopes. Despite this variability, the predominance of rapid carbonate weathering within landslides and catchments where mass wasting is prevalent results at best in limited sequestration of carbon dioxide by this process of rapid erosion. In many cases where sulfuric acid is a key weathering agent, a net release of CO2 to the atmosphere occurs. This suggests that a causal link between erosion in mountain belts and climate change through the sequestration of CO2, if it exists, must operate through a process other than chemical weathering driven by landsliding. Plain Language Summary There is a long-standing debate surrounding the link between erosion and climate. It is often suggested that as temperatures increase, rainier and stormier weather could increase erosion of rock; as that rock is exposed, silicate minerals within could break down, which, on long time scales, can remove CO2 from the atmosphere, lowering global temperatures and acting as a negative feedback. Recent studies have shown that landslide deposits are key locations for the link between chemical weathering and physical erosion in some mountain belts. To test how landslides affect the erosion-climate link, we used samples of water seeping through landslides in Taiwan and New Zealand to calculate the amount of carbon dioxide that is either absorbed or released through this chemical reaction. We find that the large amount of freshly exposed rock in Taiwanese landslide deposits contains significant carbonate rock and sulfide minerals; the net result of the weathering of these minerals is a release of carbon dioxide, which inverts the traditional perspective on the role erosion plays in controlling carbon dioxide release. In some mountain belts, it seems that increased erosion and resulting landsliding may act to increase carbon dioxide in the air, opening further questions into the nature of erosional-climatic links.
Many regions central to our understanding of tectonics and landscape evolution are active or ancient magmatic terranes, and robust interpretation of low-temperature thermochronologic ages in these settings requires careful attention to the drivers of rock heating and cooling, including magmatism. However, we currently lack a quantitative framework for evaluating the potential role of magmatic coolingthat is, post-magmatic thermal relaxationin shaping cooling age patterns in regions with a history of intrusive magmatism. Here we use analytical approximations and numerical models to characterize how low-temperature thermochronometers document cooling inside and around plutons in steadily exhuming environments. Our models predict that the thermal field a pluton intrudes into, specifically the ambient temperatures relative to the closure temperature of a given thermochronometer, is as important as the pluton size and temperature in controlling the pattern and extent of thermochronometer resetting in the country rocks around a pluton. We identify one advective and several conductive timescales that govern the relationship between the crystallization and cooling ages inside a pluton. In synthetic vertical age-elevation relationships (AERs), resetting next to plutons results in changes in AER slope that could be misinterpreted as past changes in exhumation rate if the history of magmatism is not accounted for. Finally, we find that large midcrustal plutons, such as those emplaced at similar to 10-15-km depth, can reset the low-temperature thermochronometers far above them in the upper crusta result with considerable consequences for thermochronology in arcs and regions with a history of magmatic activity that may not have a surface expression.
Imaging Raman spectroscopy can be used to identify cancerous tissue. Traditionally, a step-by-step scanning of the sample is applied to generate a Raman image, which, however, is too slow for routine examination of patients. By transferring the technique of integral field spectroscopy (IFS) from astronomy to Raman imaging, it becomes possible to record entire Raman images quickly within a single exposure, without the need for a tedious scanning procedure. An IFS-based Raman imaging setup is presented, which is capable of measuring skin ex vivo or in vivo. It is demonstrated how Raman images of healthy and cancerous skin biopsies were recorded and analyzed. (C) The Authors. Published by SPIE under a Creative Commons Attribution 3.0 Unported License.
Persistent episodes of extreme weather in the Northern Hemisphere summer have been associated with high-amplitude quasi-stationary atmospheric Rossby waves, with zonal wave numbers 6 to 8 resulting from the phenomenon of quasi-resonant amplification (QRA). A fingerprint for the occurrence of QRA can be defined in terms of the zonally averaged surface temperature field. Examining state-of-the-art [Coupled Model Intercomparison Project Phase 5 (CMIP5)] climate model projections, we find that QRA events are likely to increase by similar to 50% this century under business-as-usual carbon emissions, but there is considerable variation among climate models. Some predict a near tripling of QRA events by the end of the century, while others predict a potential decrease. Models with amplified Arctic warming yield the most pronounced increase in QRA events. The projections are strongly dependent on assumptions regarding the nature of changes in radiative forcing associated with anthropogenic aerosols over the next century. One implication of our findings is that a reduction in midlatitude aerosol loading could actually lead to Arctic de-amplification this century, ameliorating potential increases in persistent extreme weather events.
Light-emitting diodes (LEDs) are considered the future of greenhouse lighting. This study investigates the carotenoid concentrations of pak choi sprouts after growth under blue, red and white LEDs at six different time points. Furthermore, the diurnal changes of RNA transcripts of key genes of the carotenoid biosynthesis pathway as well as of the carotenoid cleavage dioxygenase 4 (CCD4) gene and of the transcription factor genes elongated hypocotyl 5 (HY5) and circadian clock associated 1 (CCA1) were investigated. The carotenoid concentrations were steady throughout the day, but showed a small maximum in the afternoon. An average total carotenoid concentration of 536 +/- 29 ng mg(-1) DM produced under white LEDs was measured, which is comparable to previously described field-grown levels. The carotenoid concentrations were slightly lower under blue or red LEDs. Moreover, the diurnal RNA transcript rhythms of most of the carotenoid biosynthesis genes showed an increase during the light period, which can be correlated to the carotenoid maxima in the afternoon. Blue LEDs caused the highest transcriptional induction of biosynthetic genes as well as of CCD4, thereby indicating an increased flux through the pathway. In addition, the highest levels of HY5 transcripts and CCA1 transcripts were determined under blue LEDs.
Objective Depression after stroke and myocardial infarction (MI) is common but often assumed to be undertreated without reliable evidence being available. Thus, we aimed to determine treatment rates and investigate the application of guidelines in these conditions. Methods Databases MEDLINE, EMBASE, PsycInfo, Web of Science, CINAHL, and Scopus were systematically searched without language restriction from inception to June 30, 2017. Prospective observational studies with consecutive recruitment reporting any antidepressant treatment in adults with depression after stroke or MI were included. Random-effects models were used to calculate pooled estimates of treatment rates. Results Fifty-five studies reported 32 stroke cohorts (n = 8938; pooled frequency of depression = 34%, 95% confidence interval [CI] = 29%-38%) and 17 MI cohorts (n = 10,767; pooled frequency of depression = 24%, 95% CI = 20%-28%). In 29 stroke cohorts, 24% (95% CI = 20%-27%) of 2280 depressed people used antidepressant medication. In 15 MI cohorts, 14% (95% CI = 8%-19%) of 2381 depressed people used antidepressant medication indicating a lower treatment rate than in stroke. Two studies reported use of psychosocial interventions, indicating that less than 10% of participants were treated. Conclusions Despite the high frequency of depression after stroke and MI and the existence of efficacious treatment strategies, people often remain untreated. Innovative strategies are needed to increase the use of effective antidepressive interventions in patients with cardiovascular disease.
Plant cultivation and processing may impact nutrient and phytochemical content of vegetables. The present study aimed at determining the influence of cultivation and processing on the health promoting capacity of African nightshade (Solanum scabrum Mill.) leaves, an indigenous vegetable, rich in nutrients and phytochemicals. Anti-genotoxicity against the human liver carcinogen aflatoxin B1 (AFB(1)) as determined by the comet assay and radical oxygen species (ROS) scavenging capacity of ethanolic and aqueous extracts were investigated in human derived liver (HepG2) cells. ROS scavenging activity was assessed using electron paramagnetic spin resonance and quantification of ARE/Nrf2 mediated gene expression. The cultivation was done under different environmental conditions. The processing included fermentation and cooking; postharvest ultraviolet irradiation (UV-C) treatment was also investigated. Overall, S. scabrum extracts showed strong health promoting potential, the highest potential was observed with the fermented extract, which showed a 60% reduction of AFB(1) induced DNA damage and a 38% reduction in FeSO4 induced oxidative stress. The content of total polyphenols, carotenoids and chlorophylls was indeed affected by cultivation and processing. Based on the present in vitro findings consumption of S. scabrum leaves could be further encouraged, preferentially after cooking or fermentation of the plant.
The variation of Rayleigh ellipticity versus frequency is gaining popularity in site characterization. It becomes a necessary observable to complement dispersion curves when inverting shear wave velocity profiles. Various methods have been proposed so far to extract polarization from ambient vibrations recorded on a single three-component station or with an array of three-component sensors. If only absolute values were recovered 10 yr ago, new array-based techniques were recently proposed with enhanced efficiencies providing also the ellipticity sign. With array processing, higher-order modes are often detected even in the ellipticity domain. We suggest to explore the properties of a high-resolution beamforming where radial and vertical components are explicitly included. If N is the number of three-component sensors, 2N x 2N cross-spectral density matrices are calculated for all presumed directions of propagation. They are built with N radial and N vertical channels. As a first approach, steering vectors are designed to fit with Rayleigh wave properties: the phase shift between radial and vertical components is either -Pi/2 or Pi/2. We show that neglecting the ellipticity tilt due to attenuation has only minor effects on the results. Additionally, we prove analytically that it is possible to retrieve the ellipticity value from the usual maximization of the high-resolution beam power. The method is tested on synthetic data sets and on experimental data. Both are reference sites already analysed by several authors. A detailed comparison with previous results on these cases is provided.
We present a new precision measurement of gas-phase abundances of S, O, N, Si, Fe, P, Al, Ca as well as molecular hydrogen (H-2) in the Leading Arm (region II, LA II) of the Magellanic Stream (MS) toward the Seyfert galaxy NGC 3783. The results are based on high-quality archival ultraviolet/optical/radio data from various different instruments (HST/STIS, FUSE, AAT, GBT, GB140 ft, ATCA). Our study updates previous results from lower-resolution data and provides for the first time a self-consistent component model of the complex multiphase absorber, delivering important constraints on the nature and origin of LA II. We derive a uniform, moderate a abundance in the two main absorber groups at +245 and +190 km s(-1) of alpha/H = 0.30 +/- 0.05 solar, a low nitrogen abundance of N/H = 0.05 +/- 0.01 solar, and a high dust content with substantial dust depletion values for Si, Fe, Al, and Ca. These a, N, and dust abundances in LA II are similar to those observed in the Small Magellanic Cloud (SMC). From the analysis of the H2 absorption, we determine a high thermal pressure of P/k approximate to 1680 K cm(-3) in LA II, in line with the idea that LA II is located in the inner Milky Way halo at a z-height of < 20 kpc, where it hydrodynamically interacts with the ambient hot coronal gas. Our study supports a scenario in which LA II stems from the breakup of a metal- and dust-enriched progenitor cloud that was recently (200-500 Myr ago) stripped from the SMC.
Full water splitting into hydrogen and oxygen on semiconductor nanocrystals is a challenging task; overpotentials must be overcome for both half-reactions and different catalytic sites are needed to facilitate them. Additionally, efficient charge separation and prevention of back reactions are necessary. Here, we report simultaneous H-2 and O-2 evolution by CdS nanorods decorated with nanoparticulate reduction and molecular oxidation co-catalysts. The process proceeds entirely without sacrificial agents and relies on the nanorod morphology of CdS to spatially separate the reduction and oxidation sites. Hydrogen is generated on Pt nanoparticles grown at the nanorod tips, while Ru(tpy)(bpy)Cl-2-based oxidation catalysts are anchored through dithiocarbamate bonds onto the sides of the nanorod. O-2 generation from water was verified by O-18 isotope labelling experiments, and time-resolved spectroscopic results confirmed efficient charge separation and ultrafast electron and hole transfer to the reaction sites. The system demonstrates that combining nanoparticulate and molecular catalysts on anisotropic nanocrystals provides an effective pathway for visible-light-driven photocatalytic water splitting.
What is the underlying diffusion process governing the spreading dynamics and search strategies employed by amoeboid cells? Based on the statistical analysis of experimental single-cell tracking data of the two-dimensional motion of the Dictyostelium discoideum amoeboid cells, we quantify their diffusive behaviour based on a number of standard and complementary statistical indicators. We compute the ensemble- and time-averaged mean-squared displacements (MSDs) of the diffusing amoebae cells and observe a pronounced spread of short-time diffusion coefficients and anomalous MSD-scaling exponents for individual cells. The distribution functions of the cell displacements, the long-tailed distribution of instantaneous speeds, and the velocity autocorrelations are also computed. In particular, we observe a systematic superdiffusive short-time behaviour for the ensemble- and time-averaged MSDs of the amoeboid cells. Also, a clear anti-correlation of scaling exponents and generalised diffusivity values for different cells is detected. Most significantly, we demonstrate that the distribution function of the cell displacements has a strongly non-Gaussian shape andusing a rescaled spatio-temporal variablethe cell-displacement data collapse onto a universal master curve. The current analysis of single-cell motions can be implemented for quantifying diffusive behaviours in other living-matter systems, in particular, when effects of active transport, non-Gaussian displacements, and heterogeneity of the population are involved in the dynamics.
Genetic studies of the Eurasian brown bear (Ursus arctos) have so far focused on populations from Europe and North America, although the largest distribution area of brown bears is in Asia. In this study, we reveal population genetic parameters for the brown bear population inhabiting the Grand Kackar Mountains (GKM) in the north east of Turkey, western Lesser Caucasus. Using both hair (N = 147) and tissue samples (N = 7) collected between 2008 and 2014, we found substantial levels of genetic variation (10 microsatellite loci). Bear samples (hair) taken from rubbing trees worked better for genotyping than those from power poles, regardless of the year collected. Genotyping also revealed that bears moved between habitat patches, despite ongoing massive habitat alterations and the creation of large water reservoirs. This population has the potential to serve as a genetic reserve for future reintroduction in the Middle East. Due to the importance of the GKM population for on-going and future conservation actions, the impacts of habitat alterations in the region ought to be minimized; e.g., by establishing green bridges or corridors over reservoirs and major roads to maintain habitat connectivity and gene flow among populations in the Lesser Caucasus.
Near-surface geophysical imaging of alluvial fan settings is a challenging task but crucial for understating geological processes in such settings. The alluvial fan of Ghor Al-Haditha at the southeast shore of the Dead Sea is strongly affected by localized subsidence and destructive sinkhole collapses, with a significantly increasing sinkhole formation rate since ca. 1983. A similar increase is observed also on the western shore of the Dead Sea, in correlation with an ongoing decline in the Dead Sea level. Since different structural models of the upper 50 m of the alluvial fan and varying hypothetical sinkhole processes have been suggested for the Ghor Al-Haditha area in the past, this study aimed to clarify the subsurface characteristics responsible for sinkhole development. For this purpose, high-frequency shear wave reflection vibratory seismic surveys were carried out in the Ghor Al-Haditha area along several crossing and parallel profiles with a total length of 1.8 and 2.1 km in 2013 and 2014, respectively. The sedimentary architecture of the alluvial fan at Ghor Al-Haditha is resolved down to a depth of nearly 200 m at a high resolution and is calibrated with the stratigraphic profiles of two boreholes located inside the survey area. The most surprising result of the survey is the absence of evidence of a thick (>2-10 m) compacted salt layer formerly suggested to lie at ca. 35-40 m depth. Instead, seismic reflection amplitudes and velocities image with good continuity a complex interlocking of alluvial fan deposits and lacustrine sediments of the Dead Sea between 0 and 200 m depth. Furthermore, the underground section of areas affected by sinkholes is characterized by highly scattering wave fields and reduced seismic interval velocities. We propose that the Dead Sea mud layers, which comprise distributed inclusions or lenses of evaporitic chloride, sulfate, and carbonate minerals as well as clay silicates, become increasingly exposed to unsaturated water as the sea level declines and are consequently destabilized and mobilized by both dissolution and physical erosion in the subsurface. This new interpretation of the underlying cause of sinkhole development is supported by surface observations in nearby channel systems. Overall, this study shows that shear wave seismic reflection technique is a promising method for enhanced near-surface imaging in such challenging alluvial fan settings.
We employ ultrafast X-ray diffraction to compare the lattice dynamics of laser-excited continuous and granular FePt films on MgO (100) substrates. Contrary to recent results on free-standing granular films, we observe in both cases a pronounced and long-lasting out-of-plane expansion. We attribute this discrepancy to the in-plane expansion, which is suppressed by symmetry in continuous films. Granular films on substrates are less constrained and already show a reduced out-of-plane contraction. Via the Poisson effect, out-of-plane contractions drive in-plane expansion and vice versa. Consistently, the granular film exhibits a short-lived out-of-plane contraction driven by ultrafast demagnetization which is followed by a reduced and delayed expansion. From the acoustic reflections of the observed strain waves at the film-substrate interface, we extract a 13% reduction of the elastic constants in thin 10 nm FePt films compared to bulk-like samples. (C) 2018 Author(s).
Woodlands and steppes
(2018)
Based on fossil organism remains including plant macrofossils, charcoal, pollen, and invertebrates preserved in syngenetic deposits of the Batagay permafrost sequence in the Siberian Yana Highlands, we reconstructed the environmental history during marine isotope stages (MIS) 6 to 2. Two fossil assemblages, exceptionally rich in plant remains, allowed for a detailed description of the palaeo-vegetation during two climate extremes of the Late Pleistocene, the onset of the last glacial maximum (LGM) and the last interglacial. In addition, altogether 41 assemblages were used to outline the vegetation history since the penultimate cold stage of MIS 6. Accordingly, meadow steppes analogue to modern communities of the phytosociological order Festucetalia lenensis formed the primary vegetation during the Saalian and Weichselian cold stages. Cold-resistant tundra-steppe communities (Carici rupestris-Kobresietea bellardii) as they occur above the treeline today were, in contrast to more northern locations, mostly lacking. During the last interglacial, open coniferous woodland similar to modern larch taiga was the primary vegetation at the site. Abundant charcoal indicates wildfire events during the last interglacial. Zoogenic disturbances of the local vegetation were indicated by the presence of ruderal plants, especially by abundant Urtica dioica, suggesting that the area was an interglacial refugium for large herbivores. Meadow steppes, which formed the primary vegetation during cold stages and provided potentially suitable pastures for herbivores, were a significant constituent of the plant cover in the Yana Highlands also under the full warm stage conditions of the last interglacial. Consequently, meadow steppes occurred in the Yana Highlands during the entire investigated timespan from MIS 6 to MIS 2 documenting a remarkable environmental stability. Thus, the proportion of meadow steppe vegetation merely shifted in response to the respectively prevailing climatic conditions. Their persistence indicates low precipitation and a relatively warm growing season throughout and beyond the late Pleistocene. The studied fossil record also proves that modern steppe occurrences in the Yana Highlands did not establish as late as in the Holocene but instead are relicts of a formerly continuous steppe belt extending from Central Siberia to Northeast Yakutia during the Pleistocene. The persistence of plants and invertebrates characteristic of meadow steppe vegetation in interior Yakutia throughout the late Quaternary indicates climatic continuity and documents the suitability of this region as a refugium also for other organisms of the Pleistocene mammoth steppe including the iconic large herbivores. (C)2018 Elsevier Ltd. All rights reserved.
Trees control the flowering processes in response to both environmental and endogenous (mechanisms at cellular/tissue level) conditions. Dormancy of flower buds is characterized by the reduction of growth and the enhancement of frost and desiccation resistance. The release of endodormancy and the beginning of ontogenetic development, as two important dates for developing reliable phenological models, escape from any visible signs. Thus, we identified - to our knowledge as first - relevant proteins in sweet cherry buds occurring during these phenological phases at high time resolution in three seasons (2012/13–2014/15) under natural conditions in Northeast Germany. The protein content of buds from the first week of October to leaf fall, from leaf fall to the end of endodormancy (t1), from t1 to the beginning of ontogenetic development (t1*), and from t1* until swollen bud, was comparable in each of the seasons. The increase of the protein content began after swollen bud and markedly differences occurred at side green, green tip, tight and open cluster. SDS gel electrophoresis followed by peptide mass fingerprinting accomplished by MALDI-TOF MS was applied for protein identification. ‘Volume intensity’ has been used to demonstrate the pattern and changes of proteins. None of the analysed proteins like for cell proliferation/differentiation (Phytosulfokines 3), carbon fixation (Rubisco), and defense against pathogenes (Major allergen Pru sv 1) indicates the date of endodormancy release or the beginning of the (invisible) ontogenetic development. The stages around green tip, tight, and open cluster resulted in markedly increase of the volume intensity of the protein for cell proliferation/differentiation and the carbon fixation, whereas the volume intensity of a protein for defense against pathogens markedly decreased. The pattern and changes of the volume intensity of neoxanthin synthase (NXS) in sweet cherry buds followed the increasing demand during endo- and ecodormancy to produce neoxanthin, which is a prominent member of the group of reactive oxygen species (ROS) scavengers.
Both enstatite spectra are very bright in the VIS and NIR and show almost neutral to slightly bluish spectral slopes with a steep absorption in the UV. Very low iron in the enstatites (below similar to 0.04 wt% FeO) already results in weak albeit noticeable absorptions in the VNIR between 0.4 and 0.9 mu m. Orthoenstatite and clinoenstatite are not distinguishable based only on their spectra in the VIS and NIR. At the Reststrahlen bands in the MIR a systematic difference in the number and exact position of local minima at similar to 10 mu m between clinoenstatite and orthoenstatite is evident. This can be used to discern between the polymorphs in this wavelength range. Additionally, we can distinguish between Fe-free low- and high-Ca pyroxenes in the MIR.
The SISAL database
(2018)
Stable isotope records from speleothems provide information on past climate changes, most particularly information that can be used to reconstruct past changes in precipitation and atmospheric circulation. These records are increasingly being used to provide "out-of-sample" evaluations of isotope-enabled climate models. SISAL (Speleothem Isotope Synthesis and Analysis) is an international working group of the Past Global Changes (PAGES) project. The working group aims to provide a comprehensive compilation of speleothem isotope records for climate reconstruction and model evaluation. The SISAL database contains data for individual speleothems, grouped by cave system. Stable isotopes of oxygen and carbon (delta O-18, delta C-13) measurements are referenced by distance from the top or bottom of the speleothem. Additional tables provide information on dating, including information on the dates used to construct the original age model and sufficient information to assess the quality of each data set and to erect a standardized chronology across different speleothems. The metadata table provides location information, information on the full range of measurements carried out on each speleothem and information on the cave system that is relevant to the interpretation of the records, as well as citations for both publications and archived data.
The use of functional music in gait training termed rhythmic auditory stimulation (RAS) and treadmill training (TT) have both been shown to be effective in stroke patients (SP). The combination of RAS and treadmill training (RAS-TT) has not been clinically evaluated to date. The aim of the study was to evaluate the efficacy of RAS-TT on functional gait in SR The protocol followed the design of an explorative study with a rater-blinded three arm prospective randomized controlled parallel group design. Forty-five independently walking SP with a hemiparesis of the lower limb or an unsafe and asymmetrical walking pattern were recruited. RAS-TT was carried out over 4 weeks with TT and neurodevelopmental treatment based on Bobath approach (NDT) serving as control interventions. For RAS-TT functional music was adjusted individually while walking on the treadmill. Pre and post-assessments consisted of the fast gait speed test (FGS), a gait analysis with the locometre (LOC), 3 min walking time test (3MWT), and an instrumental evaluation of balance (IEB). Raters were blinded to group assignments. An analysis of covariance (ANCOVA) was performed with affiliated measures from pre-assessment and time between stroke and start of study as covariates. Thirty-five participants (mean age 63.6 +/- 8.6 years, mean time between stroke and start of study 42.1 +/- 23.7 days) completed the study (11 RAS-TT, 13 TT, 11 NDT). Significant group differences occurred in the FGS for adjusted post-measures in gait velocity [F-(2,F- (34)) = 3.864, p = 0.032; partial eta(2) = 0.205] and cadence [F-(2,F- 34) = 7.656, p = 0.002; partial eta(2) = 0.338]. Group contrasts showed significantly higher values for RAS-TT. Stride length results did not vary between the groups. LOC, 3MWT, and IEB did not indicate group differences. One patient was withdrawn from TT because of pain in one arm. The study provides first evidence for a higher efficacy of RAS-TT in comparison to the standard approaches TT and NDT in restoring functional gait in SP. The results support the implementation of functional music in neurological gait rehabilitation and its use in combination with treadmill training.
Given two weighted graphs (X, b(k), m(k)), k = 1, 2 with b(1) similar to b(2) and m(1) similar to m(2), we prove a weighted L-1-criterion for the existence and completeness of the wave operators W-+/- (H-2, H-1, I-1,I-2), where H-k denotes the natural Laplacian in l(2)(X, m(k)) w.r.t. (X, b(k), m(k)) and I-1,I-2 the trivial identification of l(2)(X, m(1)) with l(2) (X, m(2)). In particular, this entails a general criterion for the absolutely continuous spectra of H-1 and H-2 to be equal.
We present the first high-resolution trace element (Mg/Ca, Sr/Ca, Ba/Ca) record from a stalagmite in southwestern Romania covering the last 3.6 ka, which provides the potential for quantitative climate reconstruction. Precise age control is based on three independent dating methods, in particular for the last 250 yr, where chemical lamina counting is combined with the identification of the 20th century radiocarbon bomb peak and Th-230/U dating. Long-term cave monitoring and model simulations of drip water and speleothem elemental variability indicate that precipitation-related processes are the main drivers of speleothem Mg/Ca ratios. Calibration against instrumental climate data shows a significant anti-correlation of speleothem Mg/Ca ratios with autumn/winter (October to March) precipitation (r = -0.61, p < 0.01), which is statistically robust when considering age uncertainties and auto-correlation. This relationship is used to develop a quantitative reconstruction of autumn/winter precipitation. During the late Holocene, our data suggest a heterogeneous pattern of past regional winter hydroclimate in the Carpathian/Balkan realm, along with intermittent weakening of the dominant influence of North Atlantic forcing. In agreement with other regional paleo-hydrological reconstructions, the observed variability reveals periodically occurring strong NW-SE hydro-climate gradients. We hypothesize, that this pattern is caused by shifts of the eastern edge of the area of influence of the NAO across central eastern Europe due to the confluence of North Atlantic forcing, and other climatic features such as the East Atlantic/Western Russia (EAWR) pattern. (C) 2018 Elsevier B.V. All rights reserved.
When knowing is believing
(2018)
In an effort to understand teachers' technology use, recent scholarship has explored the idea of technological pedagogical content knowledge (TPCK or TPACK). Many studies have used self-reports to measure this knowledge (SR TPCK). Several studies have examined the construct validity of these assessments by analysing the internal relationships of the knowledge domains, but little attention has been paid to how SR TPCK relates to external criteria. We tackled this question of discriminant validity by reanalysing 2 data sets. We used correlation and multiple regression analyses to explore whether conceptually related constructs explain any variance in participants' SR TPCK. In Study 1, we applied this strategy to German pre-service teachers using technology use, attitudinal variables, and objective measures of teachers' knowledge of technology and pedagogy as external criteria. In Study 2, we examined measures of technology knowledge, experience, and pro-technology beliefs for in-service teachers in the United States. Across both studies, a sizeable amount of the variance in SR TPCK is explained by teachers' prior technology use and pro-technology attitudes. In contrast, fact-based tests of technology and pedagogy are distinct from SR TPCK. We discuss implications for these findings and argue that researchers should gather complementary measures in concert.
The basic seismic load parameters for the upcoming national design regulation for DIN EN 1998-1/NA result from the reassessment of the seismic hazard supported by the German Institution for Civil Engineering (DIBt). This 2016 version of the national seismic hazard assessment for Germany is based on a comprehensive involvement of all accessible uncertainties in models and parameters and includes the provision of a rational framework for integrating ranges of epistemic uncertainties and aleatory variabilities in a comprehensive and transparent way. The developed seismic hazard model incorporates significant improvements over previous versions. It is based on updated and extended databases, it includes robust methods to evolve sets of models representing epistemic uncertainties, and a selection of the latest generation of ground motion prediction equations. The new earthquake model is presented here, which consists of a logic tree with 4040 end branches and essential innovations employed for a realistic approach. The output specifications were designed according to the user oriented needs as suggested by two review teams supervising the entire project. Seismic load parameters, for rock conditions of nu(S30) = 800 m/s, are calculated for three hazard levels (10, 5 and 2% probability of occurrence or exceedance within 50 years) and delivered in the form of uniform hazard spectra, within the spectral period range 0.02-3 s, and seismic hazard maps for peak ground acceleration, spectral response accelerations and for macroseismic intensities. Results are supplied as the mean, the median and the 84th percentile. A broad analysis of resulting uncertainties of calculated seismic load parameters is included. The stability of the hazard maps with respect to previous versions and the cross-border comparison is emphasized.
One paragraph of the manuscript of the paper has been inadvertently omitted in the very final stage of its compilation due to a technical mistake. Since this paragraph discusses the declustering of the used earthquake catalogue and is therefore necessary for the understanding of the seismicity data preprocessing, the authors decided to provide this paragraph in form of a correction. The respective paragraph belongs to chapter 2 of the paper, where it was placed originally, and should be inserted into the published paper before the second to the last paragraph. The omitted text reads as follows:
More than 41% of the Earth’s land area is covered by permanent or seasonally arid dryland ecosystems. Global development and human activity have led to an increase in aridity, resulting in ecosystem degradation and desertification around the world. The objective of the present work was to investigate and compare the microbial community structure and geochemical characteristics of two geographically distinct saline pan sediments in the Kalahari Desert of southern Africa. Our data suggest that these microbial communities have been shaped by geochemical drivers, including water content, salinity, and the supply of organic matter. Using Illumina 16S rRNA gene sequencing, this study provides new insights into the diversity of bacteria and archaea in semi-arid, saline, and low-carbon environments. Many of the observed taxa are halophilic and adapted to water-limiting conditions. The analysis reveals a high relative abundance of halophilic archaea (primarily Halobacteria), and the bacterial diversity is marked by an abundance of Gemmatimonadetes and spore-forming Firmicutes. In the deeper, anoxic layers, candidate division MSBL1, and acetogenic bacteria (Acetothermia) are abundant. Together, the taxonomic information and geochemical data suggest that acetogenesis could be a prevalent form of metabolism in the deep layers of a saline pan.
Cosmic-ray electrons and positrons (CREs) at GeV-TeV energies are a unique probe of our local Galactic neighborhood. CREs lose energy rapidly via synchrotron radiation and inverse-Compton scattering processes while propagating within the Galaxy, and these losses limit their propagation distance. For electrons with TeV energies, the limit is on the order of a kiloparsec. Within that distance, there are only a few known astrophysical objects capable of accelerating electrons to such high energies. It is also possible that the CREs are the products of the annihilation or decay of heavy dark matter (DM) particles. VERITAS, an array of imaging air Cherenkov telescopes in southern Arizona, is primarily utilized for gamma-ray astronomy but also simultaneously collects CREs during all observations. We describe our methods of identifying CREs in VERITAS data and present an energy spectrum, extending from 300 GeV to 5 TeV, obtained from approximately 300 hours of observations. A single power-law fit is ruled out in VERITAS data. We find that the spectrum of CREs is consistent with a broken power law, with a break energy at 710 +/- 40(stat) +/- 140(syst) GeV.
Aims. We study the evolution of an arch filament system (AFS) and of its individual arch filaments to learn about the processes occurring in them. Methods. We observed the AFS at the GREGOR solar telescope on Tenerife at high cadence with the very fast spectroscopic mode of the GREGOR Infrared Spectrograph (GRIS) in the He I 10 830 angstrom spectral range. The He I triplet profiles were fitted with analytic functions to infer line-of-sight (LOS) velocities to follow plasma motions within the AFS. Results. We tracked the temporal evolution of an individual arch filament over its entire lifetime, as seen in the He I 10 830 angstrom triplet. The arch filament expanded in height and extended in length from 13 ' to 21 '. The lifetime of this arch filament is about 30 min. About 11 min after the arch filament is seen in He I, the loop top starts to rise with an average Doppler velocity of 6 km s(-1). Only two minutes later, plasma drains down with supersonic velocities towards the footpoints reaching a peak velocity of up to 40 km s(-1) in the chromosphere. The temporal evolution of He I 10 830 angstrom profiles near the leading pore showed almost ubiquitous dual red components of the He I triplet, indicating strong downflows, along with material nearly at rest within the same resolution element during the whole observing time.