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Runoff predictions in ungauged arctic basins using conceptual models forced by reanalysis data
(2018)
Due to global warming, the problem of assessing water resources and their vulnerability to climate drivers in the Arctic region has become a focus in the recent years. This study is aimed at investigating three lumped hydrological models to predict daily runoff of large-scale Arctic basins in the case of substantial data scarcity. All models were driven only by meteorological forcing reanalysis dataset without any additional information about landscape, soil, or vegetation cover properties of the studied basins. Model parameter regionalization based on transferring the whole parameter set showed good efficiency for predictions in ungauged basins. We run a blind test of the proposed methodology for ensemble runoff predictions on five sub-basins, for which only monthly observations were available, and obtained promising results for current water resources assessment for a broad domain of ungauged basins in the Russian Arctic.
Ein diagnostisches Ziel der „Profilanalyse nach Grießhaber“ ist die Testung der grammatischen Fähigkeit zur Verbstellung im Deutschen. Zur erstmaligen Evaluation der Testgüte wurden 403 ein- und mehrsprachige Grundschulkinder randomisiert drei verschiedenen Testmaterialien zugewiesen: Testmaterial, das die Zielkompetenz spezifisch stimulierte, führte zu den besten Testergebnissen. Dies spricht für eine geringe Durchführungsobjektivität. Zudem wurden Deckeneffekte für Grundschulkinder nachgewiesen, weshalb die Profilanalyse nur wenig zwischen den Grammatikfähigkeiten der Kinder differenzieren kann. Auch die Retest-Reliabilität und Auswertungsobjektivität sind noch zu gering. Zusammenfassend wird die Testgüte hinsichtlich aller betrachteten Testgütekriterien als verbesserungswürdig bewertet. Daraus werden die Empfehlungen abgeleitet, die Profilanalyse stärker zu standardisieren und um sensitivere diagnostische Kriterien für das Grundschulalter zu ergänzen. Weitere Ziele der Profilanalyse, z. B. die Verbesserung diagnostischer Kompetenzen von Lehrkräften, sind in Folgeprojekten zu evaluieren.
Aiming at the same target
(2018)
Aims and objectives/purpose/research questions: We compared the processing of morphologically complex derived vs. inflected forms in native speakers of German and highly proficient native Russian second language (L2) learners of German. Design/methodology/approach: We measured morphological priming effects for derived and inflected German words. To ensure that priming effects were genuinely morphological, the design also contained semantic and orthographic control conditions. Data and analysis: 40 native speakers of German and 36 native Russian learners of L2 German participated in a masked-priming lexical-decision experiment. For both participant groups, priming effects for derived vs. inflected words were compared using linear mixed effects models. Findings/conclusions: While first language (L1) speakers showed similar facilitation effects for both derived and inflected primes, L2 speakers showed a difference between the two prime types, with robust priming effects only for derived, but not for inflected forms. Originality: Unlike in previous studies investigating derivation and inflection in L2 processing, priming effects for derived and inflected prime-target pairs were determined on the basis of the same target word, allowing for a direct comparison between the two morphological phenomena. In this respect, this is the first study to directly compare the processing of derived vs. inflected forms in L2 speakers. Significance/implications: The results are inconsistent with accounts predicting general L1/L2 differences for all types of morphologically complex forms as well as accounts assuming that L1 and L2 processing are based on the same mechanisms. We discuss theoretical implications for L2 processing mechanisms, and propose an explanation which can account for the data pattern.
The recent decline of Lepidoptera species strongly correlates with the increasing intensification of agriculture in Western and Central Europe. However, the effects of changed host-plant quality through agricultural fertilization on this insect group remain largely unexplored. For this reason, we tested the response of six common butterfly and moth species to host-plant fertilization using fertilizer quantities usually applied in agriculture. The larvae of the study species Coenonympha pamphilus, Lycaena phlaeas, Lycaena tityrus, Pararge aegeria, Rivula sericealis and Timandra comae were distributed according to a split-brood design to three host-plant treatments comprising one control treatment without fertilization and two fertilization treatments with an input of 150 and 300kgNha(-1)year(-1), respectively. In L.tityrus, we used two additional fertilization treatments with an input of 30 and 90kgNha(-1)year(-1), respectively. Fertilization increased the nitrogen concentration of both host-plant species, Rumex acetosella and Poa pratensis, and decreased the survival of larvae in all six Lepidoptera species by at least one-third, without clear differences between sorrel- and grass-feeding species. The declining survival rate in all species contradicts the well-accepted nitrogen-limitation hypothesis, which predicts a positive response in species performance to dietary nitrogen content. In contrast, this study presents the first evidence that current fertilization quantities in agriculture exceed the physiological tolerance of common Lepidoptera species. Our results suggest that (1) the negative effect of plant fertilization on Lepidoptera has previously been underestimated and (2) that it contributes to the range-wide decline of Lepidoptera.
We analysed recent K2 data of the short-period eclipsing binary system HW Vir, which consists of a hot subdwarf-B type primary with an M-dwarf companion. We determined the mid-times of eclipses, calculated O-C diagrams, and an average shift of the secondary minimum. Our results show that the orbital period is stable within the errors over the course of the 70 days of observations. Interestingly, the offset from mid-orbital phase between the primary and the secondary eclipses is found to be 1.62 s. If the shift is explained solely by light-travel time, the mass of the sdB primary must be 0.26 M-circle dot, which is too low for the star to be core-helium burning. However, we argue that this result is unlikely to be correct and that a number of effects caused by the relative sizes of the stars conspire to reduce the effective light-travel time measurement. After removing the flux variation caused by the orbit, we calculated the amplitude spectrum to search for pulsations. The spectrum clearly shows periodic signal from close to the orbital frequency up to 4600 mu Hz, with the majority of peaks found below 2600 mu Hz. The amplitudes are below 0.1 part-per-thousand, too low to be detected with ground-based photometry. Thus, the high-precision data from the Kepler spacecraft has revealed that the primary of the HW Vir system is a pulsating sdBV star. We argue that the pulsation spectrum of the primary in HW Vir differs from that in other sdB stars due to its relatively fast rotation that is (nearly) phase-locked with the orbit.
Relatively little is known about the relationship between Carl Menger, founder of the Austrian school of economics, and his son, Karl Menger, the mathematician, geometer, logician, and philosopher of science, whose mathematical colloquium at the University of Vienna was essential for the development of mathematical economics. Based on Karl Menger’s diaries and correspondence, the present paper considers the development and struggles of the young Karl Menger, focusing on the years 1919–23, when Vienna was a vanquished city. We discuss the various relations within the Menger family and their significance for Karl Menger’s intellectual development. Additionally, we consider his acquaintances with economists such as Knut Wicksell, David Davidson, and Eli Heckscher as well as the younger Menger’s work in economics. We shed new light on his editorship of the second edition of his father’s Grundsätze der Volkswirtschaftslehre.
Today, software has become an intrinsic part of complex distributed embedded real-time systems. The next generation of embedded real-time systems will interconnect the today unconnected systems via complex software parts and the service-oriented paradigm. Due to these interconnections, the architecture of systems can be subject to changes at run-time, e.g. when dynamic binding of service end-points is employed or complex collaborations are established dynamically. However, suitable formalisms and techniques that allow for modeling and analysis of timed and probabilistic behavior of such systems as well as of their structure dynamics do not exist so far. To fill the identified gap, we propose Probabilistic Timed Graph Transformation Systems (PTGTSs) as a high-level description language that supports all the necessary aspects of structure dynamics, timed behavior, and probabilistic behavior. We introduce the formal model of PTGTSs in this paper as well as present and formally verify a mapping of models with finite state spaces to probabilistic timed automata (PTA) that allows to use the PRISM model checker to analyze PTGTS models with respect to PTCTL properties. (C) 2018 Elsevier Inc. All rights reserved.
This article investigates the word order preferences of Tagalog-speaking adults and five- and seven-year-old children. The participants were asked to complete sentences to describe pictures depicting actions between two animate entities. Adults preferred agent-initial constructions in the patient voice but not in the agent voice, while the children produced mainly agent-initial constructions regardless of voice. This agent-initial preference, despite the lack of a close link between the agent and the subject in Tagalog, shows that this word order preference is not merely syntactically-driven (subject-initial preference). Additionally, the children’s agent-initial preference in the agent voice, contrary to the adults’ lack of preference, shows that children do not respect the subject-last principle of ordering Tagalog full noun phrases. These results suggest that language-specific optional features like a subject-last principle take longer to be acquired.
Color matters
(2018)
Concerning standardization of laboratory animal husbandry, only exiguous changes of habitat can potentially influence animal physiology or results of behavioral tests. Routinely, mice chow is dyed when different types of diets are dispensed. Given the fact that the dye itself has no effects on food odor or flavor, we wanted to test the hypothesis that the color of chow has an impact on food uptake in mice. Twelve-week-old male mice of different strains (C57BL/6J, DBA/2J, C3H/HeJ, BALB/cJ; n = 12/strain) were single-housed in PhenoMaster (R) cages. After acclimatization standard mice chow in different colors was administered. Food intake was monitored as a two-alternative choice test of different color combinations. All animals had an average food intake of 3 g/d and no preferences were observed when a combination of identically colored food was offered. Preference tests yielded significant aversion to blue food and significant attraction to yellow and green food in C57BL/6 and DBA/2J mice. In C3H/HeJ and BALB/cJ mice no color-related pattern occurred. Selected mice strains have known differences concerning functionality of their visual sense. C57BL/6 and DBA/2 mice are considered to be normal sighted at testing age, BALB/c is representative for albino strains and C3H mice carry mutations resulting in retinal alterations. Results suggesting that normal-sighted mice would be selective concerning food color when given the choice. Nevertheless, this does not influence overall quantity of food intake when animals were provided solely with food colored with a single dye. Moreover, visually impaired mice showed no color-related food preferences.
Hypothesis: An effective way for fixating vesicle structures is the insertion of monomers and cross-linking agents into their bilayer, and their subsequent polymerization can lead to the formation of polymeric nanocapsules. Particularly attractive here are vesicle systems that form spontaneously well-defined small vesicles, as obtaining such small nanocapsules with sizes below 100 nm is still challenging. Experiments: A spontaneously forming well-defined vesicle system composed of the surfactants TDMAO (tetradecyldimethylamine oxide), Pluronic L35, and LiPFOS (lithium perfluorooctylsulfonate) mixture was used as template for fixation by polymerization. Therefore, styrene monomer was incorporated into the vesicle bilayer and ultimately these structures were fixated by UV induced radical polymerization. Structural alteration of the vesicles upon loading with monomer and the cross-linker as well as the effect of subsequent polymerization in the membrane were investigated in detail by turbidity measurements, dynamic and static light scattering, (DLS, SLS), and small angle neutron scattering (SANS). Findings: The analysis showed the changes on vesicle structures due to the monomer loading, and that these structures can become permanently fixed by the polymerization process. The potential of this approach to produce well-defined nanocapsules starting from a self-assembled system and following polymerization is critically evaluated. (C) 2018 Elsevier Inc. All rights reserved.
The lateral and vertical temperature distribution in Oman is so far only poorly understood, particularly in the area between Muscat and the Batinah coast, which is the area of this study and which is composed of Cenozoic sediments developed as part of a foreland basin of the Makran Thrust Zone. Temperature logs (T-logs) were run and physical rock properties of the sediments were analyzed to understand the temperature distribution, thermal and hydraulic properties, and heat-transport processes within the sedimentary cover of northern Oman. An advective component is evident in the otherwise conduction-dominated geothermal play system, and is caused by both topography and density driven flow. Calculated temperature gradients (T-gradients) in two wells that represent conductive conditions are 18.7 and 19.5 °C km−1, corresponding to about 70–90 °C at 2000–3000 m depth. This indicates a geothermal potential that can be used for energy intensive applications like cooling or water desalinization. Sedimentation in the foreland basin was initiated after the obduction of the Semail Ophiolite in the late Campanian, and reflects the complex history of alternating periods of transgressive and regressive sequences with erosion of the Oman Mountains. Thermal and hydraulic parameters were analyzed of the basin’s heterogeneous clastic and carbonate sedimentary sequence. Surface heat-flow values of 46.4 and 47.9 mW m−2 were calculated from the T-logs and calculated thermal conductivity values in two wells. The results of this study serve as a starting point for assessing different geothermal applications that may be suitable for northern Oman.
The phi(ev) is calculated from high-resolution discharge and precipitation data for several rain events with a cumulative precipitation P-cum ranging from less than 5mm to more than 80 mm. Because of the high uncertainty of phi(ev) associated with the hydrograph separation method, phi(ev) is calculated with several methods, including graphical methods, digital filters and a tracer-based method. The results indicate that the hydrological response depends on (theta) over bar (ini): during dry conditions phi(ev) is consistently below 0.1, even for events with high and intense precipitation. Above a threshold of (theta) over bar (ini) = 34 vol % phi(ev) can reach values up to 0.99 but there is a high scatter. Some variability can be explained with a weak correlation of phi(ev) with P-cum and rain intensity, but a considerable part of the variability remains unexplained. It is concluded that threshold-based methods can be helpful to prevent overestimation of the hydrological response during dry catchment conditions. The impact of soil moisture on the hydrological response during wet catchment conditions, however, is still insufficiently understood and cannot be generalized based on the present results.
For several decades the Sant Llorenc de Montgai reservoir has experienced different problems that could affect the safety of the engineering structure. For this reason, several corrective actions have been taken over the years. Here, we present a study involving complementary geophysical methods including electrical resistivity tomography, seismic refraction tomography and frequency-domain electromagnetic surveys. The analysis of the inverted electrical resistivity tomography cross-sections combined with the seismic refraction results and land subsidence monitoring data show the likely mechanism of abnormal seepage. The areas where mortar injections were applied as a corrective measure are also clearly delineated. In addition, the evolution of the state of the embankment has been established from two successive electrical resistivity tomography surveys in the last two decades. The results show areas where corrective mortar injections have been effective, while in other areas new abnormal seepage has been detected. The lithological heterogeneity of the bedrock, especially the dissolution of gypsum-rich rocks, induced subsidence effects and caused abnormal seepage in different areas along the embankment. Our results indicate how corrective solutions can be optimized to reduce the cost of corrective engineering interventions.
For the first time, a rain signature in Global Navigation Satellite System Reflectometry (GNSS-R) observations is demonstrated. Based on the argument that the forward quasi-specular scattering relies upon surface gravity waves with lengths larger than several wavelengths of the reflected signal, a commonly made conclusion is that the scatterometric GNSS-R measurements are not sensitive to the surface small-scale roughness generated by raindrops impinging on the ocean surface. On the contrary, this study presents an evidence that the bistatic radar cross section sigma(0) derived from TechDemoSat-1 data is reduced due to rain at weak winds, lower than approximate to 6 m/s. The decrease is as large as approximate to 0.7 dB at the wind speed of 3 m/s due to a precipitation of 0-2 mm/hr. The simulations based on the recently published scattering theory provide a plausible explanation for this phenomenon which potentially enables the GNSS-R technique to detect precipitation over oceans at low winds.
Meteorological conditions during the ACLOUD/PASCAL field campaign near Svalbard in early summer 2017
(2018)
The two concerted field campaigns, Arctic CLoud Observations Using airborne measurements during polar Day (ACLOUD) and the Physical feedbacks of Arctic planetary boundary level Sea ice, Cloud and AerosoL (PASCAL), took place near Svalbard from 23 May to 26 June 2017. They were focused on studying Arctic mixed-phase clouds and involved observations from two airplanes (ACLOUD), an icebreaker (PASCAL) and a tethered balloon, as well as ground-based stations. Here, we present the synoptic development during the 35-day period of the campaigns, using near-surface and upper-air meteorological observations, as well as operational satellite, analysis, and reanalysis data. Over the campaign period, short-term synoptic variability was substantial, dominating over the seasonal cycle. During the first campaign week, cold and dry Arctic air from the north persisted, with a distinct but seasonally unusual cold air outbreak. Cloudy conditions with mostly low-level clouds prevailed. The subsequent 2 weeks were characterized by warm and moist maritime air from the south and east, which included two events of warm air advection. These synoptical disturbances caused lower cloud cover fractions and higher-reaching cloud systems. In the final 2 weeks, adiabatically warmed air from the west dominated, with cloud properties strongly varying within the range of the two other periods. Results presented here provide synoptic information needed to analyze and interpret data of upcoming studies from ACLOUD/PASCAL, while also offering unprecedented measurements in a sparsely observed region.
Inklusion
(2018)
Lehrstrategien
(2018)
Selbstgesteuertes Lernen
(2018)
This paper examines the consequences of international financial integration in a two-sector standard incomplete markets model with occupational choice under risk and financial constraints affecting entrepreneurial activity. We endogenize international productivity differences and discuss the implications of international integration for the macroeconomy, inequality, and welfare. Lending countries are characterized by tighter domestic constraints and experience an increase in gross national product, whereas the gross domestic product effect is ambiguous. We conclude that international integration is beneficial only for economies where there are substantial financial constraints on entrepreneurial activity. Otherwise, a majority of households suffer, due to the unequal distribution of welfare gains and losses across the heterogeneous population.