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The distribution and abundance of herbivores in African savannas are constrained by interactions between abiotic and biotic factors. At the species-level, herbivores face trade-offs among foraging requirements, vegetation structure and the availability of surface water that change over spatial and temporal scales. Characterizing herbivore requirements is necessary for the management of the environment in which they occur, as conservation management interventions such as fencing and artificial water provision consequently have effects on how herbivores address these trade-offs. We tested the effects of environmental attributes on the probability of presence of herbivore functional types at different distances to water in the Satara section of Kruger National Park over the period of a year. Hypotheses about species’ relative distribution and abundance were developed through a literature review of forage and water availability constraints on feeding preference and body size of herbivore. We expected strong seasonal relationships between vegetation biomass and quality, and biomass of water-dependent herbivores with increasing distance to water. Our analyses of herbivore distribution across the region confirmed broad-scale descriptions of interactions between forage requirements and water availability across a set of species which differ in functional traits.
This book brings together a distinguished group of scholars who are experts in their field. The authors are leading scholars in Indonesia and globally. It is a great challenge to write about the development of various courts of Indonesia. Dan S. Lev’s work is critical to Indonesian scholarship, and this volume pays tribute to his important work. Dan is a pioneer of social-political legal studies in Indonesia. Lawyers tend to think that the law is autonomous, in contrast to political science scholars who often view law and regulations as entirely the end product of political relations. Dan applied political science to the legal field by analysing legal institutions and the law through attention to power relations. Dan also observed relations between legal institutions and practitioners. He was of the view that the legal system could be understood through its institutions, profession and basic concepts. The autonomy of legal institutions and the legal profession is critical to protect from political influence.
THIS SPECIAL SECTION is devoted to the peculiarity of the narrative events in Goethe's texts, including his novels, novellas, and ballads. In general, narrative events can be described as irreversible, unpredictable, and meaningful in the larger plot, and as marking a transition from a state A to a state B.1 Narrative events—and that also means real events that can be described by means of narratives—are powerful and leave their marks. There probably would be no narrative without an event. The papers in this section focus on Goethe's remarkable avoidance of such events and his careful rendering of events. The goal of this section is to develop a theory of narrative events according to Goethe's literary texts. This Goethean theory of the event focuses on the “event-that-should-not-be” (or the event-that-should-not-have-been), meaning it focuses on strategies for avoiding events, or on strategies for understanding the many subtle consequences of such events—including how they initiate chains of repetition and trauma, and the possibilities of healing affected people and undoing the long-term damage such events can inflict. In particular, the papers examine the hermeneutic, therapeutic, and aesthetic dimensions of events-that-should-not-be and events-that-should-not-have-been.
When one considers the narratives and storylines in Goethe's plays, prose texts, and ballads, we first notice the absence of a clear, powerful, and paradigmatic event. In fact, there are not that many events at all. Yes, there is Werther's suicide, there is Iphigenie's refusal to go along with the sneaky plan by Pylades, there is Wilhelm's act of joining a (broke) theater company instead of fulfilling his father's wish to become a merchant, and there is Faust's wager. However, these events reveal more a negative structure of a refusal or nonaction, rather than some clear action or event. Unlike Friedrich Schiller, Goethe mostly does not write tragedies in which someone risks everything and heroically loses, with Götz von Berlichingen and Egmont being only partly exceptions. Unlike Theodor E. Lessing, Goethe does not usually build meaningful dilemmas that ask for solutions, as he does in Der Mann von funfzig Jahren (The Man of Fifty). And unlike Heinrich von Kleist, Goethe does not resort to “unheard-of” events, unless one wishes to count the little oddities of the Unterhaltungen deutscher Ausgewanderten (Conversations of German Refugees).
Technology has an outsized impact on the modern world; it is how we have tamed our frontiers. But that role is largely ignored when it comes to the Arctic frontier. Emerging technologies, especially AI, can enable desperately needed services and infrastructure—but they can also challenge ethics, law, and policy, as they usually do. For instance, autonomous icebreaker ships pose a dual-use dilemma since they can be used for both humanitarian and military purposes. As a lesson for other frontiers, this article will broadly introduce the potential role of AI in the changing Arctic and some of the ethical concerns that deserve attention before that future arrives.
Achieving high fracture toughness and maintaining high strength at the same time are main goals in materials science. In this work, scale-bridging fracture experiments on ultrafine-grained chromium (UFG, Cr) are performed at different length scales, starting from the macroscale over the microscale (in situ SEM) down to the nanoscale (in situ TEM). A quantitative assessment of the fracture toughness yields values of ∼3 MPa m1/2 in the frame of linear elastic fracture mechanics (LEFM) for the macrosamples. The in situ TEM tests reveal explicitly the occurrence of dislocation emission processes involved in energy dissipation and crack tip blunting serving as toughening mechanisms before intercrystalline fracture in UFG body-centered cubic (bcc) metals. In relation to coarse-grained Cr, in situ TEM tests, in this work, demonstrate the importance of strengthening grain boundaries as promising strategy in promoting further ductility and toughening in UFG bcc metals.
Childhood adversity (CA) increases the risk of subsequent mental health problems. Adolescent social support (from family and/or friends) reduces the risk of mental health problems after CA. However, the mechanisms of this effect remain unclear, and we speculate that they are manifested on neurodevelopmental levels. Therefore, we investigated whether family and/or friendship support at ages 14 and 17 function as intermediate variables for the relationship between CA before age 11 and affective or neural responses to social rejection feedback at age 18. We studied 55 adolescents with normative mental health at age 18 (26 with CA and therefore considered “resilient”), from a longitudinal cohort. Participants underwent a Social Feedback Task in the magnetic resonance imaging scanner. Social rejection feedback activated the dorsal anterior cingulate cortex and the left anterior insula. CA did not predict affective or neural responses to social rejection at age 18. Yet, CA predicted better friendships at age 14 and age 18, when adolescents with and without CA had comparable mood levels. Thus, adolescents with CA and normative mood levels have more adolescent friendship support and seem to have normal mood and neural responses to social rejection.
A lasting legacy of the International Polar Year (IPY) 2007–2008 was the promotion of the Permafrost Young Researchers Network (PYRN), initially an IPY outreach and education activity by the International Permafrost Association (IPA). With the momentum of IPY, PYRN developed into a thriving network that still connects young permafrost scientists, engineers, and researchers from other disciplines. This research note summarises (1) PYRN’s development since 2005 and the IPY’s role, (2) the first 2015 PYRN census and survey results, and (3) PYRN’s future plans to improve international and interdisciplinary exchange between young researchers. The review concludes that PYRN is an established network within the polar research community that has continually developed since 2005. PYRN’s successful activities were largely fostered by IPY. With >200 of the 1200 registered members active and engaged, PYRN is capitalising on the availability of social media tools and rising to meet environmental challenges while maintaining its role as a successful network honouring the legacy of IPY.
The microstructure and distribution of the elements have been studied in thin films of a near-equimolar CrNbTaTiW high entropy alloy (HEA) and films with 8 at.% carbon added to the alloy. The films were deposited by magnetron sputtering at 300°C. X-ray diffraction shows that the near-equimolar metallic film crystallizes in a single-phase body centered cubic (bcc) structure with a strong (110) texture. However, more detailed analyses with transmission electron microscopy (TEM) and atom probe tomography (APT) show a strong segregation of Ti to the grain boundaries forming a very thin Ti–Cr rich interfacial layer. The effect can be explained by the large negative formation enthalpy of Ti–Cr compounds and shows that CrNbTaTiW is not a true HEA at lower temperatures. The addition of 8 at.% carbon leads to the formation of an amorphous structure, which can be explained by the limited solubility of carbon in bcc alloys. TEM energy-dispersive X-ray spectroscopy indicated that all metallic elements are randomly distributed in the film. The APT investigation, however, revealed that carbide-like clusters are present in the amorphous film.
Chemical weed control remains a widely used component of integrated weed management strategies because of its cost-effectiveness and rapid removal of crop pests. Additionally, dicamba-plus-glyphosate mixtures are a commonly recommended herbicide combination to combat herbicide resistance, specifically in recently commercially released dicamba-tolerant soybean and cotton. However, increased spray drift concerns and antagonistic interactions require that the application process be optimized to maximize biological efficacy while minimizing environmental contamination potential. Field research was conducted in 2016, 2017, and 2018 across three locations (Mississippi, Nebraska, and North Dakota) for a total of six site-years. The objectives were to characterize the efficacy of a range of droplet sizes [150 µm (Fine) to 900 µm (Ultra Coarse)] using a dicamba-plus-glyphosate mixture and to create novel weed management recommendations utilizing pulse-width modulation (PWM) sprayer technology. Results across pooled site-years indicated that a droplet size of 395 µm (Coarse) maximized weed mortality from a dicamba-plus-glyphosate mixture at 94 L ha–1. However, droplet size could be increased to 620 µm (Extremely Coarse) to maintain 90% of the maximum weed mortality while further mitigating particle drift potential. Although generalized droplet size recommendations could be created across site-years, optimum droplet sizes within each site-year varied considerably and may be dependent on weed species, geographic location, weather conditions, and herbicide resistance(s) present in the field. The precise, site-specific application of a dicamba-plus-glyphosate mixture using the results of this research will allow applicators to more effectively utilize PWM sprayers, reduce particle drift potential, maintain biological efficacy, and reduce the selection pressure for the evolution of herbicide-resistant weeds.
Transport mechanisms in structurally ordered piezoelectric Ca3TaGa3Si2O14 (CTGS) single crystals are studied in the temperature range of 1000-1300 °C by application of the isotope 18O as a tracer and subsequent analysis of diffusion profiles of this isotope using secondary ion mass spectrometry (SIMS). Determined oxygen self-diffusion coefficients enable calculation of oxygen ion contribution to the total conductivity, which is shown to be small. Since very low contributions of the cations have to be expected, the total conductivity must be dominated by electron transport. Ion and electron conductivities are governed by different mechanisms with activation energies (1.9±0.1) eV and (1.2±0.07) eV, respectively. Further, the electromechanical losses are studied as a function of temperature by means of impedance spectroscopy on samples with electrodes and a contactless tone-burst excitation technique. At temperatures above 650 °C the conductivity-related losses are dominant. Finally, the operation of CTGS resonators is demonstrated at cryogenic temperatures and materials piezoelectric strain constants are determined from 4.2 K to room temperature.
High resolution (< 1 µm) computed tomography is an attractive tool in materials research due to its ability to non-destructively visualize the three-dimensional internal microstructures of the material. Recently, this technique has been further empowered by adding a fourth (temporal) dimension to study the time-lapse material response under load. Such studies are referred to as four-dimensional or in situ testing. In this snapshot review, we highlight three representative examples of in situ testing using synchrotron radiation computed tomography (SRCT) for composites failure analysis, measurement of local corrosion rate in alloys, and visualization and quantification of electrochemical reactions in lithium-ion batteries, as well as forward-looking integration of machine learning with in situ CT. Lastly, the future opportunities and challenges of in situ SRCT testing are discussed.
The homo- and heteroepitaxial deposition of LGS (langasite, La3Ga5SiO14) thin films on LGS single crystals, Si and SiO2 substrates by pulsed laser deposition (PLD) is demonstrated. PLD is performed at substrate temperatures up to about 700 °C and results initially in Ga deficient films. Two strategies of counterbalancing the Ga deficit are realized. First, off-stoichiometric targets with an enhanced Ga content are applied. Secondly, an increased oxygen partial pressure up to about 6 Pa is used during deposition to suppress evaporation of Ga suboxides. Combining these adaptions results in the growth of stoichiometric LGS thin films. Films deposited on LGS substrates do not show any additional X-ray diffraction reflexes nor broadening of the peaks with respect to the single crystalline substrates. Therefore, the homoepitaxial approach can be considered successful. The deposition on Si and SiO2 substrates under the same conditions leads to the formation of polycrystalline films. However, post-annealing at 800 °C increases crystallinity. Stoichiometry and homogeneous distribution of La, Ga and Si cations are confirmed by secondary neutral mass spectrometry (SNMS). The composition remains constant within the film, implying stable process parameters.
Kochia [Bassia scoparia (L.) A. J. Scott] is one of the most troublesome weeds throughout the North American Great Plains. Herbicides such as glyphosate and dicamba have been used widely to control B. scoparia for decades. However, many B. scoparia populations have evolved resistance to these herbicides due to selection. Especially, dicamba-resistant B. scoparia populations are often also found to be glyphosate-resistant. The objective of this research was to determine whether these two herbicide resistances are linked in B. scoparia. Reciprocal crosses were performed between glyphosate- and dicamba-resistant (GDR) and glyphosate- and dicamba-susceptible (GDS) B. scoparia to produce F1 and F2 progeny. Two F1 and seven F2 progeny families were screened with various doses of dicamba or glyphosate. All the F1 progeny survived both dicamba and glyphosate treatments. Chi-square analyses of F2 progeny suggest (1) glyphosate and dicamba resistances in B. scoparia are inherited via single, dominant nuclear genes; and (2) glyphosate- and dicamba-resistant genes are not linked. Thus, the dicamba and glyphosate resistances appear to have evolved independently due to intense selection but do not seem to spread together.
Various paleoclimatic records have been used to reconstruct the hydrologic history of the Altiplano, relating this history to past variability of the South American summer monsoon. Prior studies of the southern Altiplano, the location of the world’s largest salt flat, the Salar de Uyuni, and its neighbor, the Salar de Coipasa, generally agree in their reconstructions of the climate history of the past ∼24 ka. Some studies, however, have highly divergent climatic records and interpretations of earlier periods. In this study, lake-level variation was reconstructed from a ∼14-m-long sediment core from the Salar de Coipasa. These sediments span the last ∼40 ka. Lacustrine sediment accumulation was apparently continuous in the basin from ∼40 to 6 ka, with dry or very shallow conditions afterward. The fossil diatom stratigraphy and geochemical data (δ13C, δ15N, %Ca, C/N) indicate fluctuations in lake level from shallow to moderately deep, with the deepest conditions correlative with the Heinrich-1 and Younger Dryas events. The stratigraphy shows a continuous lake of variable depth and salinity during the last glacial maximum and latter stages of Marine Oxygen Isotope Stage 3 and is consistent with environmental inferences and the original chronology of a drill core from Salar de Uyuni.
Permafrost occupies 20 million square kilometres of Earth’s high-latitude and high-altitude landscapes. These regions are sensitive to climate change and human activities; hence, permafrost research is of considerable scientific and societal importance. However, the results of this research are generally not known by the general public. Communicating scientific concepts is an increasingly important task in the research world. Different ways to engage learners and incorporate narratives in teaching materials exist, yet they are generally underused. Here we report on an international scientific outreach project called “Frozen-Ground Cartoons”, which aims at making permafrost science accessible and fun for students, teachers, and parents through the creation of comic strips. We present the context in which the project was initiated, as well as recent education and outreach activities. The future phases of the project primarily involve a series of augmented reality materials, such as maps, photos, videos, and 3D drawings. With this project we aim to foster understanding of permafrost research among broader audiences, inspire future permafrost researchers, and raise public and science community awareness of polar science, education, outreach, and engagement.
The Grotte Chauvet is world renowned for the quality and diversity of its Palaeolithic art. Fire was particularly important to the occupants, providing light and producing charcoal for use in motifs. Charcoal samples were taken systematically from features associated with the two main occupation phases (Aurignacian and Gravettian). Analysis showed it to be composed almost entirely of pine (Pinus sp.), indicating the harsh climatic conditions at this period. No distinction in wood species was found between either the two occupation episodes or the various depositional contexts. The results throw new light on the cultural and palaeoenvironmental factors that influenced choices underlying the collection of wood for charcoal production.
Cognitive decline is an important complication of joint replacement surgeries in senior people.
We determined incidence rates of dementia diagnosis following endoprosthetic joint replacement surgery (upper and lower extremities). The observation period covered up to 28 quarters using German claims data comprising 154,604 cases 65 years and older. Effects were controlled for cerebrovascular and vascular risk factors, age, sex, the presence of a diagnosis of delirium, and regular prescription of sedative or analgesic drugs (SAD).
The rate of incident dementia diagnoses in people without joint replacement surgery was 21.34 per 1,000 person years, compared with 80.76 incident cases when joint replacement surgery was conducted during the quarter of the incident dementia diagnosis; rates declined to 21.77 incident cases 7 and more quarters after joint replacement surgery had taken place. This pattern was maintained when controlling for delirium diagnosis and regular prescription of SAD. Among 10,563 patients with at least one joint replacement surgery, patients with a diagnosis of delirium in the quarter of the surgery were at increased risk of a dementia diagnosis compared to patients without such a diagnosis (HR=2.00, p < 0.001).
In people surviving the high-risk phase for dementia immediately after surgery, long-term risk of dementia may reach the level of those without surgery. These findings encourage consequent perioperative management to reduce the risk of dementia as well as prospective studies of potentially beneficial effects of joint replacement surgery on mid- to long-term recovery of mobility and cognition in geriatric patients.