bluuebunny/crossref_metadata_2025 huggingface dataset:
Leaf litter quality coupled to Salix variety drives litter decomposition more than stand diversity or climate
Authors: Hoeber Stefanie , Fransson Petra , Weih Martin , Manzoni Stefano
Published: June 2020

Aims

Decomposition of leaf litter is influenced by litter quality as determined by plant genotype and environment, as well as climate and soil properties. We studied these drivers of decomposition in communities of Salix varieties, hypothesizing that decomposition rates would increase under warmer climate, in more diverse communities, and with increasing litter quality of the individual varieties.

Methods

Litter from four Salix varieties was incubated in three field trials across a latitudinal gradient from Central to Northern Europe. Litter and stand properties were measured and used as predictors of decomposition.

Results

No significant site differences in remaining mass or nitrogen were found. Instead, effects of initial leaf litter quality on decomposition were stronger than climatic effects. Litter quality of individual varieties strongly affected decomposition, while increasing litter diversity did not.

Conclusions

Decomposition was controlled by variety identity depending on site, indicating that local soil conditions affect litter quality (and thus decomposition) more than macroclimate. In mixed communities, varieties producing fast-decomposing litter enhanced the litter decomposition of other components producing slow-decomposing litter, and vice versa. This implies that site conditions partly determine which varieties affect community-level decomposition and nutrient release.
Binding Behavior of Carbonmonoxide to Gold Atoms on Ag(001)
Authors: Kuhness David , Pal Jagriti , Yang Hyun Jin , Mammen Nisha , Honkala Karoliina , Häkkinen Hannu , Schneider Wolf-Dieter , Heyde Markus , Freund Hans-Joachim
Published: June 2020

The adsorption behavior of single CO molecules at 4 K bound to Au adatoms on a Ag(001) metal surface is studied with scanning tunneling microscopy (STM) and inelastic electron tunneling spectroscopy (IETS). In contrast to earlier observations two different binding configurations are observed—one on top of a Au adatom and the other one adsorbed laterally to Au on Ag(001). Moreover, IETS reveals different low-energy vibrational energies for the two binding sites as compared to the one for a single CO molecule bound to Ag(001). Density functional theory (DFT) calculations of the adsorption energies, the diffusion barriers, and the vibrational frequencies of the CO molecule on the different binding sites rationalize the experimental findings.
Parsimonious powertrain modeling for environmental vehicle assessments: part 1—internal combustion vehicles
Authors: Geyer Roland , Malen Donald E.
Published: June 2020

Purpose

Environmental assessments of efforts to reduce vehicle fuel consumption require scientifically sound and robust fuel consumption models. The purpose of this paper is to introduce a novel method and model for calculating fuel consumption.

Method

This paper presents a method of powertrain modeling that is based on driving and powertrain physics, such as a net force approach to calculate force demand at the tire patch, and the use of engine maps to model engine efficiency.

Results

The presented method provides parsimonious open-source powertrain modeling to the environmental assessment community, thus an alternative to existing approaches. The modeling results are in agreement with existing values, while the modeling method is more flexible and avoids unnecessary approximations.

Conclusions

Existing fuel consumption modeling consists of very detailed and complex powertrain simulation models, typically not available for environmental vehicle assessments, or streamlined equation-based methods that use a mix of physical laws, engineering approximations, and sometimes accounting principles. The presented modeling method and open-source model provide a valuable alternative.
Modification of Mg2Si Phase Morphology in Mg-4Si Alloy by Sb and Nd Additions
Authors: Dong Hao , Xiang Siming , Lv Jie , Wang Yu , Li Lu , Yu Wenbin
Published: June 2020

We reported the effects of compound modification with Nd and Sb on the microstructure evolution and mechanical properties of Mg-4Si alloys. The characterization results showed that adding 1.0 wt.% Sb and 1.0 wt.% Nd to the alloy can effectively change the morphology of Mg2Si particles. The primary Mg2Si particles changed from coarse dendrites to regular polygons, and the average particle size decreased from 78.3 to 6.5 μm. Meanwhile, the Chinese eutectic Mg2Si became small short fiber. The experimental results showed that the Nd4Sb3 phase could be formed after adding 1.0 wt.% Sb and 1.0 wt.% Nd to the alloy. The Nd4Sb3 phase could act as the heterogeneous nucleation core of Mg2Si phase, which increased the nucleation rate of Mg2Si and improved the morphology of Mg2Si particles. The mechanical properties test found that the tensile properties and Brinell hardness of the alloy were improved with Sb and Nd alloyed. After adding 1.0 wt.% Sb and 1.0 wt.% Nd to the alloy, the ultimate tensile strength increased from 113 to 184 MPa, the elongation increased from 2.23 to 4.61%, and the Brinell hardness increased from 65.45 to 87.32 HB.
All inclusive
Authors: Kutscher Nadia , Richter Martina
Published: June 2020

Einführung in den Schwerpunkt; die Beiträge beleuchten verschiedene Dimensionen der gegenwärtigen Debatten um Inklusion und versuchen, die Komplexität und Verwobenheit der Diskurse und Ansätze sichtbar zu machen – ohne einfache Antworten zu geben.
Threshold harvesting as a conservation or exploitation strategy in population management
Authors: Hilker Frank M. , Liz Eduardo
Published: June 2020

Threshold harvesting removes the surplus of a population above a set threshold and takes no harvest below the threshold. This harvesting strategy is known to prevent overexploitation while obtaining higher yields than other harvesting strategies. However, the harvest taken can vary over time, including seasons of no harvest at all. While this is undesirable in fisheries or other exploitation activities, it can be an attractive feature of management strategies where removal interventions are costly and desirable only occasionally. In the presence of population fluctuations, the issue of variable harvests and population sizes becomes even more notorious. Here, we investigate the impact of threshold harvesting on the dynamics of both population size and harvests, especially in the presence of population cycles. We take into account semelparous and iteroparous life cycles, Allee effects, observation uncertainty, and demographic as well as environmental stochasticity, using generic mathematical models in discrete time. Our results show that threshold harvesting enhances multiple forms of population stability, namely persistence, constancy, resilience, and dynamic stability. We discuss plausible choices of threshold values, depending on whether the aim is resource exploitation, pest control, or the stabilization of fluctuations.
Multi-cycle Periodic Solutions of a Differential Equation with Delay that Switches Periodically
Authors: Tosato Marco , Zhang Xue , Wu Jianhong
Published: June 2020

We describe the behaviour of solutions of a scalar Delay Differential Equation (DDE) with delay that periodically switches between two constant values. Such an equation arises naturally from structured vector populations involved in a range of vector-borne diseases spreading in a periodically varying environment. We examine if and how the two different time lags and the switching time influence the existence and patterns of periodic solutions. We pay particular attention to the patterns involving multi-cycles within the prime period of the periodic solutions.
Evaluating petrol engine oil deterioration through oxidation and nitration parameters by low-cost IR sensor
Authors: Shinde H. M. , Bewoor A. K.
Published: June 2020

For the proper working of the internal combustion engine, engine oil plays a significant role. The performance of the engine is greatly affected by oil that has degenerated. In order to determine the optimal gap between oil changes, it is crucial to measure the deterioration in the engine oil. Multiple parameters like oxidation, nitration, viscosity and so on are brought into use. One of the methods used to quantify the deterioration in the engine oil is the Fourier Transform Infrared (FTIR) spectroscopy. The main parameters of the engine oil are distinguished by this method by utilizing Infrared (IR) absorption at different bandwidths. The two significant parameters in engine oil deterioration are oxidation and nitration. However, the limitation of the FTIR method is that it is more expensive and since it uses huge machinery, it requires a lot of area. Hence, the use of this method is not possible in the field area due to the need for space. It is this major limitation that is the motivation for proposing an inexpensive, yet handy system, using an IR sensor set up, in this paper. This system is used for measuring the transmittance of engine oil that has degenerated. For this paper, we collected random samples at various times from service stations that were specifically authorized. These samples were used in experiments based on the FTIR spectroscopy and UV spectrophotometer and the results were compared using the IR sensor setup. Investigation of the experimental results showed that monitoring oil transmittance using an IR sensor setup is possible, and a robust relationship between oxidation and nitration and the transmittance of the oil was observed. Moreover, a pattern of deterioration for a specific engine oil (SAE 5W30) which is utilized for passenger cars and light duty vehicles was also established.
Differential expression of lung adenocarcinoma transcriptome with signature of tobacco exposure
Authors: Hammouz Raneem Y. , Kostanek Joanna K. , Dudzisz Aleksandra , Witas Piotr , Orzechowska Magdalena , Bednarek Andrzej K.
Published: June 2020

Smoking accounts for almost 80–90% of lung cancer cases, which is also the most frequent cause of cancer-related deaths in humans. With over 60 carcinogens in tobacco smoke, cells dividing at the time of carcinogen exposure are at particular risk of neoplasia. The present study aimed to investigate global gene expression differences in lung adenocarcinoma (LUAD) tumour samples of current smokers and non-smokers, in an attempt to elucidate biological mechanisms underlying divergent smoking effects. Current and non-smoker tumour samples were analysed using bioinformatics tools, examining differences in molecular drivers of cancer initiation and progression, as well as evaluating the effect of smoking and sex on epithelial mesenchymal transition (EMT). As a result, we identified 1150 differentially expressed genes showing visible differences in the expression profiles between the smoking subgroups. The genes were primarily involved in cell cycle, DNA replication, DNA repair, VEGF, GnRH, ErbB and T cell receptor signalling pathways. Our results show that smoking clearly affected E2F transcriptional activity and DNA repair pathways including mismatch repair, base excision repair and homologous recombination. We observed that sex could modify the effects of PLA2G2A and PRG4 in LUAD tumour samples, whereas sex and smoking status might possibly have a biological effect on the EMT-related genes: HEY2, OLFM1, SFRP1 and STRAP. We also identified potential epigenetic changes smoking solely might have on EMT-related genes, which may serve as potential diagnostic and prognostic biomarkers for LUAD patients.
Cohort Trends in the Association Between Sibship Size and Educational Attainment in 26 Low-Fertility Countries
Authors: Choi Seongsoo , Taiji Riley , Chen Manting , Monden Christiaan
Published: June 2020

Children with many siblings have lower average educational attainment compared with children raised in smaller families, and this disadvantage by sibship size has been observed across many countries. We still know remarkably little, however, about how sibship size disadvantage has changed within countries and how such trends vary across countries. Using comparative data from 111 surveys from 26 low-fertility countries, we find an overall trend of growing sibship size disadvantage across cohorts in the majority of countries: between the 1931–1940 birth cohort and the 1971–1980 birth cohort, 16 of 26 countries showed a statistically significant increase in sibship size disadvantage in education, while only two countries showed a significant reduction in sibship size disadvantage. The disadvantage in years of education associated with having an additional sibling increased remarkably in post-socialist (0.3) and East Asian countries (0.34) and, to a lesser extent, Western European countries (0.2). In contrast, this disadvantage showed little change in Nordic countries (0.05) and even decreased in Anglo-Saxon countries (–0.11). We discuss explanations and implications of our comparative evidence in the context of the intergenerational transmission of education.
Design and analysis of an optimized microfluidic channel for isolation of circulating tumor cells using deterministic lateral displacement technique
Authors: Bhattacharjee Rituraj , Kumar R. , Panwala Fenil Chetankumar , Shakeel P. Mohamed
Published: June 2020

Circulating tumor cells (CTCs) are extremely scarce cells which cut off from a primary tumor and percolate into the circulation of blood flow and are, thus, critical for precise cancer detection and treatment. Deterministic lateral displacement (DLD) which exploits asymmetric splitting of laminar flow around the implanted microposts has displayed trustworthy capabilities in separating cells of varying sizes. In this research work, a microfluidic channel consisting of three symmetrically aligned inlets and outlets and embedded circular posts has been proposed which effectively separates the CTCs from lymphocytes utilizing the concept of DLD. Using a commercial software COMSOL Multiphysics 5.4, the design of the proposed microchannel has been simulated and analyzed considering an injected blood sample containing massive CTCs and slim WBCs of radii 13.5 µm and 6 µm, respectively. The proposed model of microchannel isolates the CTCs from WBCs at a comparatively higher sample mass flow rate of 4 × 10–6 kg/s and Reynolds number of 8.9 thereby operating efficiently at higher throughput, and offers excellent linearity in terms of velocity magnitude, pressure, shear rate and Reynolds number. The computational analysis of the proposed microchannel reveals that it can isolate CTCs from WBCs with better separation ratio, offers higher throughput, reduces possibilities of clogging and maintains better uniformity of pressure distribution and other flow parameters when compared with existing microchannel designs. The maximum separation ratio for CTCs and WBCs has been obtained as 84% and 96%, respectively.
Presenting a new fuzzy system for web service selection aimed at dynamic software rejuvenation
Authors: Rezaei Kalantari Kimia , Ebrahimnejad Ali , Motameni Homayun
Published: June 2020

As an effective technique to counteract software aging, software rejuvenation is applied in continuously running applications such as web service-based systems. In such systems, web services are allocated depending on the requirements of receivers and the facilities of servers. One of the challenging issues during assignment of web services is how to select the appropriate server to minimize faults. In this paper, we proposed dynamic software rejuvenation in the form of a proactive fault-tolerance technique based on fuzzy system. While including a threshold for the rejuvenation of each web service, we carried out the training phase based on the features of the service providers as well as the receivers’ requirements. The results of simulations revealed that our strategy can mitigate the failure rate of web services by 45, 40, 23, and 12% in comparison with the non-fuzzy, regression-based, Markov-based, and ACOGELS-based web service rejuvenation strategies, respectively.
Study of reaction–diffusion problem: modeling, exact analytical solution, and experimental verification
Authors: Szukiewicz Mirosław K.
Published: June 2020

Nonlinear diffusion–reaction problem was investigated experimentally for the reference reaction (hydrogenation of propylene under isothermal conditions; a slab of catalyst pellet i.e., disks of large diameter/width ratio were applied). The diffusion–reaction model in the catalyst pellet with external mass-transfer resistances was solved analytically. Dependently on parameters values, two separate solutions were found: dead zone inside the pellet does not exist or it appears. In the first case, a common model is acceptable (regular model i.e., boundary value problem), in the second one, a model includes additional condition (dead zone model i.e., free boundary problem). Analysis of the solution presented indicated that either regular or “dead zone” model correctly describes the process for specific parameter values (with the only exception—multiple steady-state region—where the correct interpretation requires the combined application of the both). This result shows that the full description of the real process includes solutions of two different BVPs. Experimental research confirmed results anticipated by theory. It allowed to draw conclusions that go beyond this particular example i.e., the regular model, commonly applied in heterogeneous catalysis, does not adequately recognize dead zone problem. If “dead zone” appears, free boundary problem has to be consider, otherwise, process simulations will be incorrect. The conclusions drawn are valid also for biofilms.
Endometriosis Patients Show an Increased M2 Response in the Peritoneal CD14+low/CD68+low Macrophage Subpopulation Coupled with an Increase in the T-helper 2 and T-regulatory Cells
Authors: Hudson Quanah J. , Ashjaei Kazem , Perricos Alexandra , Kuessel Lorenz , Husslein Heinrich , Wenzl Rene , Yotova Iveta
Published: June 2020

Endometriosis is a chronic inflammatory disease associated with an impaired immune response at the site of lesion implantation. The ability of macrophages to respond to changes in their environment is critical for an effective immune response. However, the existing knowledge of the peritoneal immune cell populations, their activation state and contribution to the immunological changes that occur in endometriosis are still controversial and inconclusive. In this study, we have examined the relative abundance of peritoneal macrophage subtypes, in women with (n = 21) versus without (n = 18) endometriosis and disease-associated changes in the adaptive T cell response. Using flow cytometry, we showed that peritoneal fluid monocyte/macrophages are composed of two populations of cells that exhibit major differences in the levels of the CD14 and CD68 markers, which we classified as the CD14+low/CD68+low and CD14+high/CD68+high subpopulations. Moreover, endometriosis-associated changes in the macrophage subtypes occurred only in the CD14+low/CD68+low subpopulation. In this subpopulation, we found an increased macrophage type 2 response that was coupled with an increase in peritoneal T-helper 2 and T-regulatory cell populations in women with endometriosis, compared with controls. In summary, this study resolves conflicting data in the literature regarding changes in the peritoneal immune cell population in endometriosis and identifies CD14+low/CD68+low macrophages as the subpopulation that changes in response to the disease.
Ultraholomorphic extension theorems in the mixed setting
Authors: Jiménez-Garrido Javier , Sanz Javier , Schindl Gerhard
Published: June 2020

The aim of this work is to generalize the ultraholomorphic extension theorems from V. Thilliez in the weight sequence setting and from the authors in the weight function setting (of Roumieu type) to a mixed framework. Such mixed results have already been known for ultradifferentiable classes and it seems natural that they have ultraholomorphic counterparts. In order to have control on the opening of the sectors in the Riemann surface of the logarithm for which the extension theorems are valid we are introducing new mixed growth indices which are generalizing the known ones for weight sequences and functions. As it turns out, for the validity of mixed extension results the so-called order of quasianalyticity (introduced by the second author for weight sequences) is becoming important.
MITCHELL-INSPIRED FORCING, WITH SMALL WORKING PARTS AND COLLECTIONS OF MODELS OF UNIFORM SIZE AS SIDE CONDITIONS, AND GAP-ONE SIMPLIFIED MORASSES
Authors: MORGAN CHARLES
Published: June 2020

We show that a
$(\kappa ^{+},1)$
-simplified morass can be added by a forcing with working parts of size smaller than
$\kappa $
. This answers affirmatively the question, asked independently by Shelah and Velleman in the early 1990s, of whether it is possible to do so.

Our argument use a modification of a technique of Mitchell’s for adding objects of size
$\omega _2$
in which collections of models – all of equal, countable size – are used as side conditions. In our modification, whilst the individual models are, as in Mitchell’s technique, taken ad hoc from quite general classes, the collections of models are very highly structured, in a way that is somewhat different from, perhaps more stringent than, Mitchell’s original, arguably making the method more wieldy and giving the prospect of further uses with more delicate working parts.
A New Annual14C Dataset for Calibrating the Thera Eruption
Authors: Friedrich Ronny , Kromer Bernd , Wacker Lukas , Olsen Jesper , Remmele Sabine , Lindauer Susanne , Land Alexander , Pearson Charlotte
Published: June 2020

Annually resolved tree-ring samples of the time period 1625–1510 BCE were analyzed from the German oak tree-ring chronology. Blocks of the same tree rings were previously used to generate IntCal calibration data. The new dataset shows an offset to the calibration data IntCal13 of 24 years and resembles annual data for the same time period derived from tree-ring records in other growth locations. A subset of samples of the period 1625–1585 BCE was additionally measured in three other laboratories (ETH, AAR, AA) for quality control.
HUMAN DIETARY COMPLEXITY IN TIANSHAN REGION AND THE INFLUENCE OF CLIMATE ON HUMAN PALEODIET
Authors: Zhao Haiyan , Zhou Weijian , Du Hua , Cheng Peng , Jia Peter Weiming , Gong Wei
Published: June 2020

With the popularization of carbon and nitrogen stable-isotope analysis methods used on archaeological samples from Xinjiang, the ancient paleodiet there has been revealed. However, research about isotopic analysis combined with environmental factors is rare, especially in such a variable and complex climate as that of the Tianshan region. We systematically analyzed the δ13C and δ15N results from animals and humans for dietary reconstruction of nomadic pastoralists from the Tianshan region during 3900–1200 cal BP. The δ13C and δ15N values for animals (sheep/goat, horse and cattle; n = 57) have a wide range from –20.8‰ to –14.7‰ for δ13C (–19.2 ± 1.0‰) and 3.2‰ to 9.9‰ for δ15N (7.0 ± 1.2‰). The δ13C and δ15N values from humans range from –19.6 to –12.3‰ (–16.0 ± 1.5‰) and 7.1 to 16.7‰ (–13.6 ± 1.5‰), respectively. The animal δ15N results indicate that the dry environment in the Tianshan region may result in elevated δ15N values. Synthesizing animal and human isotope results suggests that the inhabitants engaged in mobile herding economies subsidized with crops and wild animal meat from the Tianshan Mountains. In conclusion, we found that the regional environment closely relates to crop types, and temporal climate change has an effect on human dietary structure. Therefore, climate condition cannot be ignored when studying human paleodiet.
Terrestrial kaolin deposits trapped in Miocene karstic sinkholes on planation surface remnants, Transdanubian Range, Pannonian Basin (Hungary)
Authors: Kelemen Péter , Csillag Gábor , Dunkl István , Mindszenty Andrea , Kovács Ivett , von Eynatten Hilmar , Józsa Sándor
Published: June 2020

In the Transdanubian Range, Pannonian Basin, Hungary, karstic sinkholes on a planation surface of Triassic carbonates are filled by grey clayey–silty kaolin deposits. The provenance and accumulation age of these strongly altered terrestrial karst-filling sediments are constrained by X-ray powder diffraction, heavy mineral analysis and zircon U–Pb dating. The heavy minerals of the Southern Bakony Mountains samples are dominated by the ultra-stable zircon–rutile–tourmaline association. Zircon U–Pb data indicate accumulation between 20 and 16 Ma. Furthermore, Archaean to Palaeogene grains were also determined, reflecting the principally fluvial recycling of Eocene bauxites and their cover sequences. In contrast, the sample from the Keszthely Hills consists almost exclusively of airborne material including zircons of 18–14 Ma, reflecting a dominant contribution from the Carpathian–Pannonian Neogene volcanism. The shift in the Miocene age components is inferred to have been caused by the landscape evolution and burial history of the planation surface remnants controlled by local block tectonics.
Do Women Make More Credible Threats? Gender Stereotypes, Audience Costs, and Crisis Bargaining
Authors: Schwartz Joshua A. , Blair Christopher W.
Published: June 2020

As more women attain executive office, it is important to understand how gender dynamics affect international politics. Toward this end, we present the first evidence that gender stereotypes affect leaders’ abilities to generate audience costs. Using survey experiments, we show that female leaders have political incentives to combat gender stereotypes that women are weak by acting “tough” during international military crises. Most prominently, we find evidence that female leaders, and male leaders facing female opponents, pay greater inconsistency costs for backing down from threats than male leaders do against fellow men. These findings point to particular advantages and disadvantages women have in international crises. Namely, female leaders are better able to tie hands—an efficient mechanism for establishing credibility in crises. However, this bargaining advantage means female leaders will also have a harder time backing down from threats. Our findings have critical implications for debates over the effects of greater gender equality in executive offices worldwide.
Economic Growth and the Development of Real Wages: Swedish Construction Workers’ Wages in Comparative Perspective, 1831–1900
Authors: Ericsson Johan , Molinder Jakob
Published: June 2020

Using new and uniquely detailed data, we examine how construction workers’ wages in Sweden developed between 1831 and 1900. Wages grew rapidly from the 1850s, and comparisons with Northwestern Europe show that Swedish workers benefited more from growth than workers elsewhere. Globalization forces, most notably overseas migration, in combination with flexible and well-integrated labor markets—signified by strong regional convergence, falling skill differentials, and small urban-rural wage gaps—pushed up wages in Sweden.
Acoustic correlates of lexical stress in Moroccan Arabic
Authors: Bruggeman Anna , Louriz Nabila , Almbark Rana , Hellmuth Sam
Published: June 2020

Presently there is no consensus regarding the interpretation and analysis of the stress system of Moroccan Arabic. This paper tests whether the acoustic realisation of syllables support one widely adopted interpretation of lexical stress, according to which stress is either penultimate or final depending on syllable weight. The experiment reports on word-initial syllables that differ in presumed stress status. Target words were embedded in a carrier sentence within a scripted mock dialogue to ensure that the measurements reflect lexical stress rather than phrase-level prominence. Results from all four acoustic parameters tested (f0, duration, Centre of Gravity and vowel quality) showed that there were no differences as a function of presumed stress status, thus failing to support an interpretation according to which stressed syllables are acoustically differentiated. We consider the results in relation to previous claims and observations, and conclude that the absence of acoustic correlates of presumed stress is compatible with the view that Moroccan Arabic lacks lexical stress.
A Goudstikker van Goyen in Gdańsk: A Case Study of Nazi-Looted Art in Poland
Authors: Grimsted Patricia Kennedy
Published: June 2020

This article traces the provenance and migration of a painting by Jan van Goyen (1595–1656),River Landscape with a Swineherd, from the Jacques Goudstikker Collection and now in Gdańsk Muzeum Narodowe. After the “red-flag sale” of the Goudstikker Collection in July 1940 to German banker Alois Miedl, and then to Hermann Göring, this painting—after its sale on Berlin’s Lange Auction in December 1940 to Hitler’s agent Almas-Dietrich—was returned to Miedl-Goudstikker in Amsterdam. Miedl then sold it (with two other Dutch paintings) to the Nazi Gauleiter of Danzig, Albert Forster, among many wartime Dutch acquisitions for the Municipal Museum (Stadtmuseum). Evacuated to Thuringia and captured by a Soviet trophy brigade, it thus avoided postwar Dutch claims. Returned to Poland from the Hermitage in 1956, it was exhibited in the Netherlands and the United States (despite its Goudstikker label). Tracing its wartime and postwar odyssey highlights the transparent provenance research needed for Nazi-era acquisitions, especially in former National Socialist (NS) Germanized museums in countries such as Poland, where viable claims procedures for Holocaust victims and heirs are still lacking. This example of many “missing” Dutch paintings sold to NS-era German museums in cities that became part of postwar Poland, raises several important issues deserving attention in provenance research for still-displaced Nazi-looted art.
Quasi-elliptic dual-band bandpass filters based on series-cascaded multi-resonant cells
Authors: Ashley Andrea , Simpson Dakotah J. , Psychogiou Dimitra
Published: June 2020

This paper reports on quasi-elliptic dual-band bandpass filters (BPFs) that were designed for the Filter Student Design Competition of the 2019 European Microwave Week. The proposed lumped-element (LE) BPF concept is based on two dual-band transversal cells and one multi-resonant cell that allow the realization of symmetric and asymmetric dual-band transfer functions shaped by six poles and five transmission zeros. A compact implementation scheme based on LE series resonators is proposed for size compactness and wide spurious free out-of-band response. For proof-of-concept demonstration purposes, a dual-band LE prototype with two passbands centered 1 and 1.5 GHz was designed, manufactured, and measured. It exhibited the following radio frequency measured performance characteristics. Passbands centered at 1.02 and 1.45 GHz, minimum insertion loss levels of 2.0 and 2.7 dB, and bandwidth of 146 and 105 MHz, respectively, for the first and the second passband, and out-of-band rejection >30 dB between 0 and 894 MHz, 1.17–1.34 GHz, and 1.72–6.9 GHz.
Giant reed (Arundo donax) responses to herbicides in a greenhouse study
Authors: Liu Mingyang , Hulting Andrew , Mallory-Smith Carol
Published: June 2020

Giant reed recently was promoted as a biofuel crop in Oregon. Because giant reed is a highly invasive plant in North American rivers, the planting of this species in Oregon is a cause for concern to scientists and local land managers. However, some growers in the area were interested in producing giant reed as a rotational crop. To find potential herbicides to control the giant reed or to control it as a volunteer, 13 foliar and 13 cut-and-spray herbicide treatments were preevaluated in greenhouse studies. We chose 10% and 85% reduction in aboveground biomass for either crop safety or control, respectively. When applied at the standard rates, acetochlor and dimethenamid-p reduced aboveground dry biomass of the crop by 10% or less. Acetochlor+atrazine, atrazine, flufenacet, and mesotrione reduced aboveground biomass of the crop by at least 85%, indicating that these compounds have the potential to serve as controls against giant reed.
Arbeitsengagement zur Messung von positiver beruflicher Beanspruchung im Lehrberuf – eine berufsübergreifende Validierung
Authors: Sandmeier Anita , Mandel Debbie
Published: June 2020

Zusammenfassung. Die Forschung zu Beanspruchung im Lehrberuf ist nach wie vor stark auf negative Auswirkungen wie Stress, Erschöpfung und Burnout fokussiert. Um ein vollständiges Bild zu erhalten, müssen auch die positiven Aspekte von Beanspruchung analysiert werden. Dafür bietet sich ein Konstrukt an, das sich in der internationalen arbeits- und organisationspsychologischen Forschung in den vergangenen Jahren durchgesetzt und in verschiedenen Berufsfeldern und nationalen Kontexten bewährt hat: Arbeitsengagement, gemessen mit der Utrecht Work Engagement Scale (UWES). Der vorliegende Beitrag analysiert die deutschsprachige Version der 9-Item Version der UWES an einer Stichprobe von Lehrerinnen und Lehrern ( N = 162) im Vergleich mit Personen aus intellektuell-forschenden Berufen ( N = 195). Konfirmatorische Mehrgruppen-Faktoranalysen zeigten, dass die UWES-9 über beide Berufsgruppen hinweg messinvariant ist. Die latente Mittelwertsanalyse ergab, dass die Lehrerinnen und Lehrer in Bezug auf das Arbeitsengagement besser abschneiden als die Fachkräfte der anderen Gruppe. Dabei hängt das Arbeitsengagement in beiden Gruppen wie erwartet positiv mit affektivem organisationalem Commitment und negativ mit der Kündigungsabsicht zusammen, was die Validität der deutschen Version des Tests belegt. Vor dem Hintergrund dieser Erkenntnisse wird am Schluss des Beitrags das Potenzial des Konstrukts für die Erforschung der positiven Beanspruchung im Lehrberuf diskutiert.
Response of the Equatorial Ionosphere to the Annular Solar Eclipse of 15 January 2010
Authors: Jose Lijo , Vineeth C. , Pant T. K. , Kumar K. K.
Published: June 2020

This paper presents the response of the equatorial ionosphere to the noon time annular solar eclipse of 15 January 2010. The observation has been made using a Digisonde, Meteor Wind Radar, and Proton Precession Magnetometer over Trivandrum, (8.5oE; 77oN; dip lat 0.5oN), a geomagnetic dip equatorial station in India. It has been found that the E, F1, and F2 regions of the equatorial ionosphere respond to solar eclipse with different time delays, F1 being responding faster and the E and F2 regions slower. Though there have been studies on the delayed response of F2 region during the solar eclipses, the delayed response of E region is quite unexpected since this region is dominated by the recombination chemistry. The plausible reasons for this have been explored, and it is suggested that the downward diffusion of atomic oxygen plays a major role for the observed phenomenon.
Volcanic Processes in the Gassendi Region of the Moon
Authors: Giguere Thomas A. , Hawke B. Ray , Gillis‐Davis Jeffrey J. , Lemelin Myriam , Boyce Joseph M. , Trang David , Lawrence Samuel J. , Stopar Julie D. , Campbell Bruce A. , Gaddis Lisa R. , Blewett David T. , Gustafson J. Olaf , Peterson Chris A. , Runyon Cassandra R.
Published: June 2020

The lunar floor‐fractured crater Gassendi and surrounding area were examined with high‐resolution Lunar Reconnaissance Orbiter imagery and other remote sensing data to characterize and understand the volcanic processes in the southwestern region of the Moon. This study was selected because the Gassendi region exhibits a variety of volcanic features (e.g., cryptomaria deposits, pyroclastic deposits, maria, and lava lakes) and team participants have studied this region for 30 years (Hawke et al., 1991, https://doi.org/10.1029/92GL02921). This study confirms the existence of a previously identified cryptomare deposit and identifies an additional cryptomare deposit west of Gassendi crater and a pyroclastic northeast of Gassendi. Spectral and geochemical anomalies associated with dark‐haloed impact craters reveal cryptomaria deposits in the western Gassendi crater floor and previously unmapped mare basalt within northeastern Gassendi. We identified three separate lava lakes on the northeast, northwest, and southwest floor of Gassendi crater based on morphology analogous to terrestrial lava lakes, geochemical signatures, and digital terrain data. Crater count (model) age data suggest that the lava lakes were active at ~3.6 Ga (300 Ma after floor emplacement). Criteria used to identify lava lakes in Gassendi were applied globally to locate candidate lava lakes within floor‐fractured craters. With the identification of lava lake morphology, both in Gassendi crater and in other floor‐fractured craters, the current ascent and eruption models should be revised to allow for at least short‐term connection between magma supply at depth and surface lava lakes. Hence, this integration of multiple perspectives afforded by recent remote data sets reveals new views about lunar volcanic processes.
Evolution and Propagation of an Active Plate Boundary: U‐Pb Ages of Fault‐Related Calcite From the Dead Sea Transform
Authors: Oren Omer , Nuriel Perach , Kylander‐Clark Andrew R. C. , Haviv Itai
Published: June 2020

We utilize in situ U‐Pb geochronology of fault‐related calcite to date faulting activity along the Dead Sea Transform (DST) plate boundary and constrain the evolution of continental breakup. U‐Pb ages from 30 well‐constrained Tera‐Wasserburg data sets of syntectonic calcite precipitates along the northern part of the DST delineate two key periods of faulting activity: (1) Maastricht (latest Cretaceous) to Eocene (70–37 Ma) and (2) middle Miocene (18–10 Ma). The latter period is more extensive and is associated with normal and left‐lateral shearing deformation. Ages of ~18 Ma, obtained from the western and eastern most strands (~20 km apart), indicate that branching in the northern DST occurred during the initial stage of the DST development. Comparison of the new ages from the northern part of the DST with U‐Pb ages from the southern part highlights prominent faulting activity during the early to middle Miocene (20–10 Ma), with earliest ages of ~18 Ma in the south and younger ages of ~14 Ma in the north. This pattern suggests that the genesis of this plate boundary started adjacent to the Red Sea rift and migrated from south to north during a 3.5–4 Ma period (between 18 and 14 Ma) at an average rate of 11–13 cm/year. Such propagation data can be used to decipher the mechanical evolution of the lithosphere along evolving plate boundaries.
Pre‐breakup Extension in the Northern North Sea Defined by Complex Strain Partitioning and Heterogeneous Extension Rates
Authors: Claringbould Johan S. , Bell Rebecca E. , Jackson Christopher A.‐L. , Gawthorpe Robert L. , Odinsen Tore
Published: June 2020

The early stages of continental rifting are accommodated by the growth of upper crustal normal fault systems that are distributed relatively evenly across the rift width. Numerous fault systems define fault arrays, the kinematics of which are poorly understood due to a lack of regional studies drawing on high‐quality subsurface data. Here we investigate the long‐term (~150 Myr) growth of a rift‐related fault array in the East Shetland Basin, northern North Sea, using a regionally extensive subsurface data set comprising 2‐D and 3‐D seismic reflection surveys and 107 boreholes. We show that rift‐related strain during the pre‐Triassic to Middle Triassic was originally distributed across several subbasins. The Middle to Late Triassic saw a decrease in extension rate (~14 m/Myr) as strain localized in the western part of the basin. Early Jurassic strain initially migrated eastward, before becoming more diffuse during the main, Middle‐to‐Late Jurassic rift phase. The highest extension rates (~89 m/Myr) corresponded with the main rift event in the East Shetland Basin, before focusing of strain within the rift axis and ultimate abandonment of the East Shetland Basin in the Early Cretaceous. We also demonstrate marked spatial variations in timing and magnitude of slip along strike of major fault systems during this protracted rift event. Our results imply that strain migration patterns and extension rates during the initial, prebreakup phase of continental rifting may be more complex than previously thought; this reflects temporal and spatial changes in both thermal and mechanical properties of the lithosphere, in addition to varying extension rates.
How to Improve Space Weather Forecasting
Authors: Zastrow Mark
Published: June 2020

The field of space weather forecasting could take cues from its Earthly counterpart to increase the reliability of models as well as warning times ahead of inbound solar storms.
This Week: Diversity Outdoors and in School
Authors:   AGU
Published: June 2020

What Earth and space science stories are we recommending this week?
Geoscience Commits to Racial Justice. Now We’ve Got Work to Do
Authors: Cartier Kimberly
Published: June 2020

To be silent is to be complicit in our own destruction because racism destroys us all. But not being silent entails more than publishing statements. There is also the collective silence of inaction. —No Time for Silence
Wintertime Particulate Matter Decrease Buffered by Unfavorable Chemical Processes Despite Emissions Reductions in China
Authors: Leung Danny M. , Shi Hongrong , Zhao Bin , Wang Jing , Ding Elizabeth M. , Gu Yu , Zheng Haotian , Chen Gang , Liou Kuo‐Nan , Wang Shuxiao , Fast Jerome D. , Zheng Guangjie , Jiang Jingkun , Li Xiaoxiao , Jiang Jonathan H.
Published: June 2020

Extreme and persistent haze events frequently occur during wintertime China. While recent emissions reductions reduced annual mean fine particulate matter (PM2.5) concentrations over eastern China, their effectiveness on wintertime PM2.5 trend remains uncertain. We use observations and model simulations to quantify seasonal differences in PM2.5 trends and investigate the underlying chemical mechanisms driving such differences. We find a much slower decrease in observed wintertime PM2.5 (−3.2% yr−1) since 2014, in contrast to a drastic summertime decrease (−10.3% yr−1). Simulations show two previously underappreciated mechanisms buffering wintertime PM2.5 decrease, including an increase in oxidation capacity due to nitrogen oxides (NOx) reductions under wintertime volatile organic compound (VOC)‐limited chemistry, and an enhanced conversion of nitric acid to nitrate by ammonia due to sulfur dioxide reductions. Our findings suggest that control policies targeting VOC and deep NOx reductions are needed to improve wintertime PM2.5 air quality over China.
Marine Nitrous Oxide Emissions From Three Eastern Boundary Upwelling Systems Inferred From Atmospheric Observations
Authors: Ganesan A. L. , Manizza M. , Morgan E. J. , Harth C. M. , Kozlova E. , Lueker T. , Manning A. J. , Lunt M. F. , Mühle J. , Lavric J. V. , Heimann M. , Weiss R. F. , Rigby M.
Published: June 2020

Eastern Boundary Upwelling Systems (EBUSs) are coastal hotspots of the potent greenhouse gas nitrous oxide (N2O). However, estimates of their emissions suffer from large uncertainties due to their significant spatial and temporal heterogeneity. Here, we derive the first multiyear, monthly resolution N2O emissions from three of the four major EBUSs using high‐frequency coastal atmospheric measurements and an inverse method. We find average combined N2O emissions from the northern California, Benguela, and southern Canary upwelling systems to be 57.7 (51.4–63.9) Gg‐N yr−1. We also find an offshore region near the Benguela EBUS that exhibits large pulses of emissions with emissions that reach 677 Gg‐N yr−1 in 1 month. Our findings highlight that atmospheric measurements coupled with inverse modeling can capture the large variability in EBUS emissions by quantifying emissions over large spatial distances and over long time periods compared to previous methods using traditional oceanographic measurements.
Observations of Buried Lake Drainage on the Antarctic Ice Sheet
Authors: Dunmire D. , Lenaerts J. T. M. , Banwell A. F. , Wever N. , Shragge J. , Lhermitte S. , Drews R. , Pattyn F. , Hansen J. S. S. , Willis I. C. , Miller J. , Keenan E.
Published: June 2020

Between 1992 and 2017, the Antarctic Ice Sheet (AIS) lost ice equivalent to 7.6 ± 3.9 mm of sea level rise. AIS mass loss is mitigated by ice shelves that provide a buttress by regulating ice flow from tributary glaciers. However, ice‐shelf stability is threatened by meltwater ponding, which may initiate, or reactivate preexisting, fractures, currently poorly understood processes. Here, through ground penetrating radar (GPR) analysis over a buried lake in the grounding zone of an East Antarctic ice shelf, we present the first field observations of a lake drainage event in Antarctica via vertical fractures. Concurrent with the lake drainage event, we observe a decrease in surface elevation and an increase in Sentinel‐1 backscatter. Finally, we suggest that fractures that are initiated or reactivated by lake drainage events in a grounding zone will propagate with ice flow onto the ice shelf itself, where they may have implications for its stability.
Turbulent Mixing in a Loop Current Eddy From Glider‐Based Microstructure Observations
Authors: Molodtsov S. , Anis A. , Amon R. M. W. , Perez‐Brunius P.
Published: June 2020

Turbulence parameters have been estimated from microstructure velocity and temperature measurements in an anticyclonic Loop Current Eddy in the Gulf of Mexico for the very first time. Measurements were performed during a mission in October 2016, using a G2 Webb Research Slocum ocean glider instrumented with a microstructure sensors suite. Well‐defined turbulent kinetic energy dissipation rate patterns in the eddy and the surface mixed layer were clearly identified from both the velocity and temperature microstructure data. Higher dissipation rates were observed at the flanks and beneath the eddy core (up to 10−7 W/kg), while the core interior appeared to be very quiescent (~10−11 W/kg). Double diffusive thermohaline intrusions were detected on the side of the eddy, while the region below the eddy core was more conducive for salt fingering. Heat and salt fluxes associated with these processes suggest that a life span of such an eddy is ~1.5 years.
The Effect of Mineral Dissolution on the Effective Stress Law for Permeability in a Tight Sandstone
Authors: Ma Jin , Querci Lorenzo , Hattendorf Bodo , Saar Martin O. , Kong Xiang‐Zhao
Published: June 2020

We present flow‐through experiments to delineate the processes involved in permeability changes driven by effective stress variations and mineral cement dissolution in porous rocks. CO2‐enriched brine is injected continuously into a tight sandstone under in situ reservoir conditions for 455 hrs. Due to the dolomite cement dissolution, the bulk permeability of the sandstone specimen significantly increases, and two dissolution passages are identified near the fluid inlet by X‐ray CT imaging. Prereaction and postreaction examinations of the effective stress law for permeability suggest that after reaction, the bulk permeability is more sensitive to pore pressure changes and less sensitive to effective stress changes. These observations are corroborated by Scanning Electron Microscopy and X‐ray CT observations. This study deepens our understanding of the effect of mineral dissolution on the effective stress law for permeability, with implications for characterizing subsurface mass and energy transport, particularly during fluid injection/production into/from geologic reservoirs.