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Thomson scatter radars have successfully measured plasma parameters in the ionosphere for over 60 years. Fundamentally, the radars measure increased power returns when the Bragg scattering condition is met by a source of density fluctuations in the plasma. Typically, wave modes of the plasma provide the source of structuring, and the radars measure strong power returns at the ion line which is associated with the ion-acoustic mode, the gyro line which is associated with the electrostatic whistler mode, and the plasma line that comes from the Langmuir mode. However, the existence of an ion-acoustic mode or electrostatic whistler mode is not guaranteed in the ionosphere. In this study, a formalism is developed to explain non-resonant wave modes as features occurring at frequencies where the dielectric function has a local minimum as opposed to a root corresponding to the typical resonant wave mode. With this formalism, the frequency of non-resonant waves is numerically solved as a function of basic plasma parameters. By solving for minima of the dielectric function, the frequency and intensity of gyro lines is determined for a wide range of plasma temperatures and densities. This analysis explains why Arecibo gyro lines are typically weak in intensity and result from non-resonant waves. For VHF systems like EISCAT, gyro lines are shown to be strong spectral peaks corresponding to standard resonant solutions for electrostatic whistler waves. 

Abstract Despite documented ecomorphological shifts toward an herbivorous diet in several coelurosaurian lineages, the evolutionary tempo and mode of these changes remain poorly understood, hampered by sparse cranial materials for early representatives of major clades. This is particularly true for Therizinosauria, with representative crania best known for the late‐divergingErlikosaurus andrewsiand the early taxonJianchangosaurus yixianensis. Here we describe a series of new cranial bones ofFalcarius utahensis, the geologically oldest therizinosaurian from the Early Cretaceous Cedar Mountain Formation, Utah, United States. This new material provides the most complete understanding of the skull to date forFalcariusand frames the pattern and timing of cranial evolution in therizinosaurians and early coelurosaurians. Previously unknown elements include a well‐preserved maxilla, jugal, parietals, squamosal, laterosphenoids, and pterygoid. Computed tomography data differentiate the incisiform rostral dentary dentition from possible premaxillary teeth, the first in a therizinosaurian. Notable features include a primitive morphology of the jugal and frontoparietal complex shared with other early diverging taxa (e.g., tyrannosauroids,Incisivosaurus,Ornitholestes, Fukuivenator), and a large maxillary fenestra, convergent with troodontids. Additional specimens of previously known elements confirm their taxonomic utility and provide insight into intraspecific variation. Following patterns of other archosaurs, variable traits relate to the prominence of ridges and contours (likely associated with musculature) and the proportions of pneumatic features, whereas invariant traits correspond to the topology of bony contacts and major cranial nerves. Early, integrated evolution of the rostrum and adductor complex characterized early therizinosaurians, which was further modified alongside reduced paranasal complexity in later therizinosaurids. 

Transparent conductive oxides (TCOs) are a high-performance material system that could enable new wearable sensors and electronics, but traditional fabrication methods face scalability and performance challenges. In this work, we utilize liquid metal printing to produce ultrathin two-dimensional (2D) indium tin oxide (ITO) films with superior microstructural, optical, and electrical properties compared to conventional techniques. We investigate the dynamics of grain growth and its influence on conductivity and the optical properties of 2D ITO, demonstrating the tunability through annealing and multilayer deposition. Additionally, we develop Au-decorated transparent electrodes, showcasing their adhesion and flexibility, low contact impedance, and biocompatibility. Leveraging the transparency of these electrodes, we enable enhanced simultaneous multimodal biosignal acquisition by integrating biopotential-based methods, such as electrocardiogram (ECG) or bioimpedance sensing (e.g., impedance plethysmography, IPG), with optical modalities like photoplethysmography (PPG). This study establishes CLMP-fabricated flexible 2D TCOs as a versatile platform for advanced bioelectronic systems and multimodal diagnostics. 

This study extends current work on strategic framing into strategic decision making associated with regional economic development. Regional government decision makers deploy strategic management steps including interpretation of internal/external task environment, choosing possible strategies, and implementing them towards advancing the interests of their communities. Viewing their strategies through a Dynamic Capabilities perspective, we analyze the Comprehensive Economic Development Strategies (CEDS) of 91 counties in the Pacific Northwest and factors associated with rural and metro regional development. Results suggest a negative relationship between rurality, but no relationship with median home value, and the Sensing and Seizing components of DC’s when controlling for income. 

Plant leaf waxes and their isotopic composition are important tracers of ecological, environmental, and climate variability, with strong preservation potential in sedimentary archives. However, they represent an integrated, and often complicated, signal of vegetation and hydrology within a watershed. Here, we report a new approach for examining complex mixtures of n-alkanes in sediments and their isotope values: non-negative matrix factorization (NMF). NMF identifies the endmembers in a mixture from the integrated n-alkane data and provides quantitative information on the relative importance of those endmembers across samples. We apply this approach to a synthetic dataset and two previously published datasets to illustrate its uses. Our application of NMF to re-analyse previously published data reveals new insights into past climate and ecological change. We demonstrate that NMF allows a user to 1) identify potential mixing problems, 2) evaluate which specific compounds in a mixture carry the isotope signal that can best address a given scientific objective, 3) determine compound concentrations after excluding contributions from particular endmember sources, and 4) calculate isotope values of different sources. NMF provides a quantitative approach for evaluating the influence of endmember mixing on molecular concentrations and isotope values within a dataset. The re-analysis of two published datasets reveals new quantitative insight into Holocene Arctic climate and Neogene vegetation change.