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The early exhumation history of the Tauern Window in the European Eastern Alps and its surface expression is poorly dated and quantified, partly because thermochronological and provenance information are sparse from the Upper Austrian Northern Alpine Foreland Basin. For the first time, we combine a single-grain double-dating approach (Apatite Fission Track and U-Pb dating) with trace-element geochemistry analysis on the same apatites to reconstruct the provenance and exhumation history of the late Oligocene/early Miocene Eastern Alps. The results from 22 samples from the Chattian to Burdigalian sedimentary infill of the Upper Austrian Northern Alpine Foreland Basin were integrated with a 3D seismic-reflection data set and published stratigraphic reports. Our highly discriminative data set indicates an increasing proportion of apatites (from 6% to 23%) with Sr/Y values <0.1 up-section and an increasing amount of apatites (from 24% to 38%) containing >1,000 ppm light rare-earth elements from Chattian to Burdigalian time. The number of U-Pb ages with acceptable uncertainties increases from 40% to 59% up-section, with mostly late Variscan/Permian ages, while an increasing number of grains (10%-27%) have Eocene or younger apatite fission track cooling ages. The changes in the apatite trace-element geochemistry and U-Pb data mirror increased sediment input from an >= upper amphibolite-facies metamorphic source of late Variscan/Permian age - probably the otztal-Bundschuh nappe system - accompanied by increasing exhumation rates indicated by decreasing apatite fission track lag times. We attribute these changes to the surface response to upright folding and doming in the Penninic units of the future Tauern Window starting at 29-27 Ma. This early period of exhumation (0.3-0.6 mm/a) is triggered by early Adriatic indentation along the Giudicarie Fault System.
We investigate the failed partial eruption of a filament system in NOAA AR 12104 on 2014 July 5, using multiwavelength EUV, magnetogram, and H alpha observations, as well as magnetic field modeling. The filament system consists of two almost co-spatial segments with different end points, both resembling a C shape. Following an ejection and a precursor flare related to flux cancellation, only the upper segment rises and then displays a prominent twisted structure, while rolling over toward its footpoints. The lower segment remains undisturbed, indicating that the system possesses a double-decker structure. The erupted segment ends up with a reverse-C shape, with material draining toward its footpoints, while losing its twist. Using the flux rope insertion method, we construct a model of the source region that qualitatively reproduces key elements of the observed evolution. At the eruption onset, the model consists of a flux rope atop a flux bundle with negligible twist, which is consistent with the observational interpretation that the filament possesses a double-decker structure. The flux rope reaches the critical height of the torus instability during its initial relaxation, while the lower flux bundle remains in stable equilibrium. The eruption terminates when the flux rope reaches a dome-shaped quasi-separatrix layer that is reminiscent of a magnetic fan surface, although no magnetic null is found. The flux rope is destroyed by reconnection with the confining overlying flux above the dome, transferring its twist in the process.
Natural gas can be temporarily stored in a variety of underground facilities, such as depleted gas and oil fields, natural aquifers and caverns in salt rocks. Being extensively monitored during operations, these systems provide a favourable opportunity to investigate how pressure varies in time and space and possibly induces/triggers earthquakes on nearby faults. Elaborate and detailed numerical modelling techniques are often applied to study gas reservoirs. Here we show the possibilities and discuss the limitations of a flexible and easily formulated tool that can be straightforwardly applied to simulate temporal pore-pressure variations and study the relation with recorded microseismic events. We use the software POEL (POroELastic diffusion and deformation) which computes the poroelastic response to fluid injection/extraction in a horizontally layered poroelastic structure. We further develop its application to address the presence of vertical impermeable faults bounding the reservoir and of multiple injection/extraction sources. Exploiting available information on the reservoir geometry and physical parameters, and records of injection/extraction rates for a gas reservoir in southern Europe, we perform an extensive parametric study considering different model configurations. Comparing modelled spatiotemporal pore-pressure variations with in situ measurements, we show that the inclusion of vertical impermeable faults provides an improvement in reproducing the observations and results in pore-pressure accumulation near the faults and in a variation of the temporal pore-pressure diffusion pattern. To study the relation between gas storage activity and recorded local microseismicity, we applied different seismicity models based on the estimated porepressure distribution. This analysis helps to understand the spatial distribution of seismicity and its temporal modulation. The results show that the observed microseismicity could be partly linked to the storage activity, but the contribution of tectonic background seismicity cannot be excluded.
The administrative language used in imperial and city chanceries illustrates formal language use in the Early Modern period, as most evident in its syntactic complexity. Since administrative language was considered prestigious by the literate people of the time, the syntactic features in question are increasingly found in other text types as well (Lötscher 1995, Schwitalla 2002). The present paper investigates early newspapers published in the seventeenth and eighteenth centuries to evalute their degree of syntactic complexity and hence the extent of formal language used. Contrary to common belief (Admoni 1980, von Polenz 2013), it will be shown that early newspapers do not allow a uniform assessment in terms of their syntactic complexity, when they emerge as a new genre in the seventeenth century: some news segments display a fairly simple syntax, whereas others are of high syntactic complexity. By the end of the eighteenth century, the growing conventionalization of the new genre as well as the impact of standardization processes render newspapers much more balanced in terms of syntactic complexity. Unlike previous work on the syntactic complexity of newspaper language, the measurement of syntactic complexity takes into account not only sentence length and the relationship between independent and dependent clauses, but also the placement of adverbial clauses in relation to their associated clause.
Reservoir-triggered seismicity has been observed near dams during construction, impoundment, and cyclic filling in many parts of the earth. In Turkey, the number of dams has increased substantially over the last decade, with Ataturk Dam being the largest dam in Turkey with a total water capacity of 48.7 billion m(3). After the construction of the dam, the monitoring network has improved. Considering earthquakes above the long-term completeness magnitude of M-C = 3.5, the local seismicity rate has substantially increased after the filling of the reservoir. Recently, two damaging earthquakes of M-w 5.5 and M-w 5.1 occurred in the town of Samsat near the Ataturk Reservoir in 2017 and 2018, respectively. In this study, we analyze the spatio-temporal evolution of seismicity and its source properties in relation to the temporal water-level variations and the stresses resulting from surface loading and pore-pressure diffusion. We find that water-level and seismicity rate are anti-correlated, which is explained by the stabilization effect of the gravitational induced stress imposed by water loading on the local faults. On the other hand, we find that the overall effective stress in the seismogenic zone increased over decades due to pore-pressure diffusion, explaining the enhanced background seismicity during recent years. Additionally, we observe a progressive decrease of the Gutenberg-Richter b-value. Our results indicate that the stressing rate finally focused on the region where the two damaging earthquakes occurred in 2017 and 2018.
Synthesis of organic-inorganic hybrids based on the conjugated polymer P3HT and mesoporous silicon
(2022)
Organic-inorganic hybrids are a class of functional materials that combine favorable properties of their constituents to achieve an overall improved performance for a wide range of applications. This article presents the synthesis route for P3HT-porous silicon hybrids for thermoelectric applications. The conjugated polymer P3HT is incorporated into the porous silicon matrix by means of melt infiltration. Gravimetry, sorption isotherms and energy dispersive X-ray spectroscopy (EDX) mapping indicate that the organic molecules occupy more than 50% of the void space in the inorganic host. We demonstrate that subsequent diffusion-based doping of the confined polymer in a FeCl3 solution increases the electrical conductivity of the hybrid by five orders of magnitude compared to the empty porous silicon host.
The accelerating climatic changes and new infrastructure development across the Arctic require more robust risk and environmental assessment, but thus far there is no consistent record of human impact. We provide a first panarctic satellite-based record of expanding infrastructure and anthropogenic impacts along all permafrost affected coasts (100 km buffer, approximate to 6.2 Mio km(2)), named the Sentinel-1/2 derived Arctic Coastal Human Impact (SACHI) dataset. The completeness and thematic content goes beyond traditional satellite based approaches as well as other publicly accessible data sources. Three classes are considered: linear transport infrastructure (roads and railways), buildings, and other impacted area. C-band synthetic aperture radar and multi-spectral information (2016-2020) is exploited within a machine learning framework (gradient boosting machines and deep learning) and combined for retrieval with 10 m nominal resolution. In total, an area of 1243 km(2) constitutes human-built infrastructure as of 2016-2020. Depending on region, SACHI contains 8%-48% more information (human presence) than in OpenStreetMap. 221 (78%) more settlements are identified than in a recently published dataset for this region. 47% is not covered in a global night-time light dataset from 2016. At least 15% (180 km(2)) correspond to new or increased detectable human impact since 2000 according to a Landsat-based normalized difference vegetation index trend comparison within the analysis extent. Most of the expanded presence occurred in Russia, but also some in Canada and US. 31% and 5% of impacted area associated predominantly with oil/gas and mining industry respectively has appeared after 2000. 55% of the identified human impacted area will be shifting to above 0 C-circle ground temperature at two meter depth by 2050 if current permafrost warming trends continue at the pace of the last two decades, highlighting the critical importance to better understand how much and where Arctic infrastructure may become threatened by permafrost thaw.
This article presents inelastic thermal neutron scattering experiments probing the phonon dispersion in mesoporous silicon with pores 8 nm across. Scattering studies reveal the energy-momentum relation for transverse and longitudinal phonons along the high symmetry directions , and in the Brillouin zone. The dispersion up to phonon energies of 35 meV unambiguously proves that the phonon group velocities in highly-crystalline silicon are not modified by nanostructuring down to sub-10 nanometer length scales. On these length scales, there is apparently no effect of structuring on the elastic moduli of mesoporous silicon. No evidence can be found for phonon-softening in topologically complex, geometrically disordered mesoporous silicon putting it in contrast to silicon nanotubes and nanoribbons.
Instructional videos are widely used to study teachers' professional vision. A new technological development in video research is mobile eye-tracking (MET). It has the potential to provide fine-grained insights into teachers' professional vision in action, but has yet been scarcely employed. We addressed this research gap by using MET video feedback to examine how expert and novice teachers differed in their noticing and weighing of alternative teaching strategies. Expert and novice teachers' lessons were recorded with MET devices. Then, they commented on what they observe while watching their own teaching videos. Using a mixed methods approach, we found that expert and novice teachers did not differ in the number of classroom events they noticed and alternative teaching strategies they mentioned. However, novice teachers were more critical of their own teaching than expert teachers, particularly when they considered alternative teaching strategies. Practical implications for the field of teacher education are discussed.
We revise the conceptual model of calcite varves and present, for the first time, a dual lake monitoring study in two alkaline lakes providing new insights into the seasonal sedimentation processes forming these varves. The study lakes, Tiefer See in NE Germany and Czechowskie in N Poland, have distinct morphology and bathymetry, and therefore, they are ideal to decipher local effects on seasonal deposition. The monitoring setup in both lakes is largely identical and includes instrumental observation of (i) meteorological parameters, (ii) chemical profiling of the lake water column including water sampling, and (iii) sediment trapping at both bi-weekly and monthly intervals. We then compare our monitoring data with varve micro-facies in the sediment record. One main finding is that calcite varves form complex laminae triplets rather than simple couplets as commonly thought. Sedimentation of varve sub-layers in both lakes is largely dependent on the lake mixing dynamics and results from the same seasonality, commencing with diatom blooms in spring turning into a pulse of calcite precipitation in summer and terminating with a re-suspension layer in autumn and winter, composed of calcite patches, plant fragments and benthic diatoms. Despite the common seasonal cycle, the share of each of these depositional phases in the total annual sediment yield is different between the lakes. In Lake Tiefer See calcite sedimentation has the highest yields, whereas in Lake Czechowskie, the so far underestimated re-suspension sub-layer dominates the sediment accumulation. Even in undisturbed varved sediments, re-suspended material becomes integrated in the sediment fabric and makes up an important share of calcite varves. Thus, while the biogeochemical lake cycle defines the varves' autochthonous components and micro-facies, the physical setting plays an important role in determining the varve sub-layers' proportion.
Non-alcoholic fatty liver disease (NAFLD), as a consequence of overnutrition caused by high-calorie diets, results in obesity and disturbed lipid homeostasis leading to hepatic lipid droplet formation. Lipid droplets can impair hepatocellular function; therefore, it is of utmost importance to degrade these cellular structures. This requires the normal function of the autophagic-lysosomal system and the ubiquitin-proteasomal system. We demonstrated in NZO mice, a polygenic model of obesity, which were compared to C57BL/6J (B6) mice, that a high-fat diet leads to obesity and accumulation of lipid droplets in the liver. This was accompanied by a loss of autophagy efficiency whereas the activity of lysosomal proteases and the 20S proteasome remained unaffected. The disturbance of cellular protein homeostasis was further demonstrated by the accumulation of 3-nitrotyrosine and 4-hydroxynonenal modified proteins, which are normally prone to degradation. Therefore, we conclude that fat accumulation in the liver due to a high-fat diet is associated with a failure of autophagy and leads to the disturbance of proteostasis. This might further contribute to lipid droplet stabilization and accumulation.
Large earthquakes can increase the amount of water feeding stream flows, raise groundwater levels, and thus grant plant roots more access to water in water-limited environments. We examine growth and photosynthetic responses of Pine plantations to the Maule M-w 8.8 earthquake in headwater catchments of Chile's Coastal Range. We combine high-resolution wood anatomic (lumen area) and biogeochemical (delta 13C of wood cellulose) proxies of daily to weekly tree growth sampled from trees on floodplains and close to ridge lines. We find that, immediately after the earthquake, at least two out of six tree trees on valley floors had increased lumen area and decreased delta 13C, while trees on hillslopes had a reverse trend. Our results indicate a control of soil water on this response, largely consistent with models that predict how enhanced postseismic vertical soil permeability causes groundwater levels to rise on valley floors, but fall along the ridges. Statistical analysis with boosted regression trees indicates that streamflow discharge gained predictive importance for photosynthetic activity on the ridges, but lost importance on the valley floor after the earthquake. We infer that earthquakes may stimulate ecohydrological conditions favoring tree growth over days to weeks by triggering stomatal opening. The weak and short-lived signals that we identified, however, show that such responses are only valid under water-limited, rather than energy-limited tree, growth. Hence, dendrochronological studies targeted at annual resolution may overlook some earthquake effects on tree vitality.
The use of post-processing heat treatments is often considered a necessary approach to relax high-magnitude residual stresses (RS) formed during the layerwise additive manufacturing laser powder bed fusion (LPBF). In this work, three heat treatment strategies using temperatures of 450 degrees C, 800 degrees C, and 900 degrees C are applied to austenitic stainless steel 316L samples manufactured by LPBF. These temperatures encompass the suggested lower and upper bounds of heat treatment temperatures of conventionally processed 316L. The relaxation of the RS is characterized by neutron diffraction (ND), and the associated changes of the microstructure are analyzed using electron backscattered diffraction (EBSD) and scanning electron microscopy (SEM). The lower bound heat treatment variant of 450 degrees C for 4 hours exhibited high tensile and compressive RS. When applying subsequent heat treatments, we show that stress gradients are still observed after applying 800 degrees C for 1 hour but almost completely vanish when applying 900 degrees C for 1 hour. The observed near complete relaxation of the RS appears to be closely related to the evolution of the characteristic subgrain solidification cellular microstructure.
The vertical flux of marine snow particles significantly reduces atmospheric carbon dioxide concentration. In the mesopelagic zone, a large proportion of the organic carbon carried by sinking particles dissipates thereby escaping long term sequestration. Particle associated prokaryotes are largely responsible for such organic carbon loss. However, links between this important ecosystem flux and ecological processes such as community development of prokaryotes on different particle fractions (sinking vs. non-sinking) are yet virtually unknown. This prevents accurate predictions of mesopelagic organic carbon loss in response to changing ocean dynamics. Using combined measurements of prokaryotic heterotrophic production rates and species richness in the North Atlantic, we reveal that carbon loss rates and associated microbial richness are drastically different with particle fractions. Our results demonstrate a strong negative correlation between prokaryotic carbon losses and species richness. Such a trend may be related to prokaryotes detaching from fast-sinking particles constantly enriching non-sinking associated communities in the mesopelagic zone. Existing global scale data suggest this negative correlation is a widespread feature of mesopelagic microbes.
The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) mission carries magnetometers that are dedicated to enhance the satellite's navigation. After appropriate calibration and characterisation of artificial magnetic disturbances, these observations are valuable assets to characterise the natural variability of Earth's magnetic field. We describe the data pre-processing, the calibration, and characterisation strategy against a high-precision magnetic field model applied to the GRACE-FO magnetic data. During times of geomagnetic quiet conditions, the mean residual to the magnetic model is around 1 nT with standard deviations below 10 nT. The mean difference to data of ESA's Swarm mission, which is dedicated to monitor the Earth's magnetic field, is mainly within +/- 10 nT during conjunctions. The performance of GRACE-FO magnetic data is further discussed on selected scientific examples. During a magnetic storm event in August 2018, GRACE-FO reveals the local time dependence of the magnetospheric ring current signature, which is in good agreement with results from a network of ground magnetic observations. Also, derived field-aligned currents (FACs) are applied to monitor auroral FACs that compare well in amplitude and statistical behaviour for local time, hemisphere, and solar wind conditions to approved earlier findings from other missions including Swarm. On a case event, it is demonstrated that the dual-satellite constellation of GRACE-FO is most suitable to derive the persistence of auroral FACs with scale lengths of 180 km or longer. Due to a relatively larger noise level compared to dedicated magnetic missions, GRACE-FO is especially suitable for high-amplitude event studies. However, GRACE-FO is also sensitive to ionospheric signatures even below the noise level within statistical approaches. The combination with data of dedicated magnetic field missions and other missions carrying non-dedicated magnetometers greatly enhances related scientific perspectives.
Antarctica is the last pristine environment on Earth, its biota being adapted to the harsh and extreme polar climate. Until now, soil formation and vegetation development in continental Antarctica were considered very slow due to the extreme conditions of this polar desert. Since the austral summer 2002/2003, a long-term monitoring network of the terrestrial ecosystems (soils, vegetation, active layer thickness) has been established at Victoria Land (VL) across a > 500 km latitudinal gradient of coastal sites (73 degrees -77 degrees S). In only one decade large ecosystem changes were detected. Climate was characterized by a significant increase of thawing degree days in northern VL and of autumn air temperature. No extreme climatic events (such as hot spells) where detected in the study period. Soil chemistry suffered large quantitative changes, clearly indicating rapid pedogenetic processes. In most soils the upper layers exhibited a strong alkalinization (pH increases up to 3 units) and increases in conductivity, anions and cations (in particular of SO4 and Na). The largest changes were observed in soils with low vegetation cover. Statistically significant differences in soil chemistry were detected between soils with high and low vegetation cover, the former showing lower pH, conductivity, Na and Cl. Most plots exhibited changes of total cover, species richness and floristic composition, with vegetation expansion in soils with low vegetation cover and the largest increase recorded at Apostrophe Island (northern VL). Principal Component Analysis (PCA) identified the main trend of vegetation change, with a shift from lower to higher cover and a secondary trend of change associated with a gradient of water availability, consistent with an increase in water instead of snow. Redundancy analysis (RDA) identified the trend of change in soil chemistry with increases in pH, conductivity, anions and cations associated with the concomitant decrease in C, N, NO3, PO4. The RDA confirmed that soil changes were associated with a gradient of vegetation change (from low to high cover) as well as of water availability, as already indirectly outlined by the PCA. Field manipulation experiments carried out at five locations of the network between 73 degrees S and 77 degrees S, simulating increases of precipitation from snow or water additions didn't induce changes in soil pH, indicating that pulse events of snow accumulation or melting could not trigger persistent soil pH changes. These data allow hypothesize the occurrence of a main ecosystem change occurring at regional scale at Victoria Land. The slight air warming and its consequences on soil chemistry and vegetation, further highlight the sensitivity of the fragile Antarctic ecosystems to the consequences of even small changes in climate.
Seafloor spreading at slow rates can be accommodated on large-offset oceanic detachment faults (ODFs), that exhume lower crustal and mantle rocks in footwall domes termed oceanic core complexes (OCCs). Footwall rocks experience large rotation during exhumation, yet important aspects of the kinematics-particularly the relative roles of solid-block rotation and flexure-are not clearly understood. Using a high-resolution numerical model, we explore the exhumation kinematics in the footwall beneath an emergent ODF/OCC. A key feature of the models is that footwall motion is dominated by solid-block rotation, accommodated by the nonplanar, concave-down fault interface. A consequence is that curvature measured along the ODF is representative of a neutral stress configuration, rather than a "bent" one. Instead, it is in the subsequent process of "apparent unbending" that significant flexural stresses are developed in the model footwall. The brittle strain associated with apparent unbending is produced dominantly in extension, beneath the OCC, consistent with earthquake clustering observed in the Trans-Atlantic Geotraverse at the Mid-Atlantic Ridge.
We consider sedimented at a solid wall particles that are immersed in water containing small additives of photosensitive ionic surfactants. It is shown that illumination with an appropriate wavelength, a beam intensity profile, shape and size could lead to a variety of dynamic, both unsteady and steady state, configurations of particles. These dynamic, well-controlled and switchable particle patterns at the wall are due to an emerging diffusio-osmotic flow that takes its origin in the adjacent to the wall electrostatic diffuse layer, where the concentration gradients of surfactant are induced by light. The conventional nonporous particles are passive and can move only with already generated flow. However, porous colloids actively participate themselves in the flow generation mechanism at the wall, which also sets their interactions that can be very long ranged. This light-induced diffusio-osmosis opens novel avenues to manipulate colloidal particles and assemble them to various patterns. We show in particular how to create and split optically the confined regions of particles of tunable size and shape, where well-controlled flow-induced forces on the colloids could result in their crystalline packing, formation of dilute lattices of well-separated particles, and other states.
Mental health of Japanese workers: amotivation mediates self-compassion on mental health problems
(2022)
Workplace mental health is a cause for concern in many countries. Globally, 78% of the workforce experienced impairment of their mental health in 2020. In Japan, more than half of employees are mentally distressed.
Previously, research has identified that self-compassion (i.e., being kind and understanding towards oneself) and work motivation were important to their mental health.
However, how these three components relate to each other remains to be elucidated. Accordingly, this study aimed to examine the relationship between mental health problems, self-compassion and work motivation (i.e., intrinsic motivation, extrinsic motivation and amotivation).
A cross-sectional design was employed, where 165 Japanese workers completed self-report scales regarding those three components. A correlation and path analyses were conducted.
Mental health problems were positively associated with amotivation and negatively associated with age and self-compassion. While intrinsic motivation and extrinsic motivation did not mediate the impact of self-compassion on mental health problems, amotivation did.
The findings can help managers and organizational psychologists help identify effective approaches to improving work mental health.
Fungal biotransformation is an attractive synthetic strategy to produce highly specific compounds with chemical functionality in regions of the carbon skeleton that are not easily activated by conventional organic chemistry methods.
In this work, Cladosporium antarcticum isolated from sediments of Glacier Collins in Antarctica was used to obtain novel drimane sesquiterpenoids alcohols with activity against Candida yeast from drimendiol and epidrimendiol. These compounds were produced by the high-yield reduction of polygodial and isotadeonal with NaBH4 in methanol.
Cladosporium antarcticum produced two major products from drimendiol, identified as 9 alpha-hydroxydrimendiol (1, 41.4 mg, 19.4% yield) and 3 beta-hydroxydrimendiol (2, 74.8 mg, 35% yield), whereas the biotransformation of epidrimendiol yielded only one product, 9 beta-hydroxyepidrimendiol (3, 86.6 mg, 41.6% yield).
The products were purified by column chromatography and their structure elucidated by NMR and MS. The antifungal activity of compounds 1-3 was analyzed against Candida albicans, C. krusei and C. parapsilosis, showing that compound 2 has a MIC lower than 15 mu g/mL against the three-pathogenic yeast.
In silico studies suggest that a possible mechanism of action for the novel compounds is the inhibition of the enzyme lanosterol 14 alpha-demethylase, affecting the ergosterol synthesis.