1,080 research outputs found
Gazing at the Solar System: Capturing the Evolution of Dunes, Faults, Volcanoes, and Ice from Space
Gazing imaging holds promise for improved understanding of surface
characteristics and processes of Earth and solar system bodies. Evolution of
earthquake fault zones, migration of
sand dunes, and retreat of ice masses
can be understood by observing
changing features over time.
To gaze or stare means to look
steadily, intently, and with fixed
attention, offering the ability to probe
the characteristics of a target deeply,
allowing retrieval of 3D structure and
changes on fine and coarse scales.
Observing surface reflectance and 3D
structure from multiple perspectives
allows for a more complete view of a
surface than conventional remote
imaging. A gaze from low Earth orbit
(LEO) could last several minutes
allowing for video capture of dynamic
processes. Repeat passes enable
monitoring time scales of days to years.
Numerous vantage points are available during a gaze (Figure 1). Features in
the scene are projected into each image frame enabling the recovery of dense
3D structure. The recovery is robust to errors in the spacecraft position and
attitude knowledge, because features are from different perspectives. The
combination of a varying look angle and the solar illumination allows recovering
texture and reflectance properties and permits the separation of atmospheric
effects. Applications are numerous and diverse, including, for example, glacier
and ice sheet flux, sand dune migration, geohazards from earthquakes,
volcanoes, landslides, rivers and floods, animal migrations, ecosystem changes,
geysers on Enceladus, or ice structure on Europa.
The Keck Institute for Space Studies (KISS) hosted a workshop in June of
2014 to explore opportunities and challenges of gazing imaging. The goals of the
workshop were to develop and discuss the broad scientific questions that can be
addressed using spaceborne gazing, specific types of targets and applications,
the resolution and spectral bands needed to achieve the science objectives, and
possible instrument configurations for future missions.
The workshop participants found that gazing imaging offers the ability to
measure morphology, composition, and reflectance simultaneously and to
measure their variability over time. Gazing imaging can be applied to better
understand the consequences of climate change and natural hazards processes,
through the study of continuous and episodic processes in both domains
Frontiers in nanoscale electrochemical imaging : faster, multifunctional and ultrasensitive
A wide range of interfacial physicochemical processes, from electrochemistry to the functioning of living cells involve spatially localized chemical fluxes that are associated with specific features of the interface. Scanning electrochemical probe microscopes (SEPMs) represent a powerful means of visualizing interfacial fluxes, and this Feature Article highlights recent developments that have radically advanced the speed, spatial resolution, functionality and sensitivity of SEPMs. A major trend has been a coming together of SEPMs that developed independently, and the use of established SEPMs in completely new ways, greatly expanding their scope and impact. The focus is on nanopipette-based SEPMs, including scanning ion conductance microscopy (SICM), scanning electrochemical cell microscopy (SECCM), and hybrid techniques thereof, particularly with scanning electrochemical microscopy (SECM). Nanopipette-based probes are made easily, quickly and cheaply with tunable characteristics. They are reproducible and can be fully characterized, and their reponse can be modeled in considerable detail, so that quantitative maps of chemical fluxes and other properties (e.g. local charge) can be obtained and analyzed. This article provides an overview on the use of these probes for high speed imaging, to create movies of electrochemical processes in action, to carry out multifunctional mapping, such as simultaneous topography-charge and topography-activity, and to create nanoscale electrochemical cells for the detection, trapping and analysis of single entities, particularly individual molecules and nanoparticles (NPs). These studies provide a platform for the further application and diversification of SEPMs across a wide range of interfacial science
Emotionotopy in the human right temporo-parietal cortex
AbstractHumans use emotions to decipher complex cascades of internal events. However, which mechanisms link descriptions of affective states to brain activity is unclear, with evidence supporting either local or distributed processing. A biologically favorable alternative is provided by the notion of gradient, which postulates the isomorphism between functional representations of stimulus features and cortical distance. Here, we use fMRI activity evoked by an emotionally charged movie and continuous ratings of the perceived emotion intensity to reveal the topographic organization of affective states. Results show that three orthogonal and spatially overlapping gradients encode the polarity, complexity and intensity of emotional experiences in right temporo-parietal territories. The spatial arrangement of these gradients allows the brain to map a variety of affective states within a single patch of cortex. As this organization resembles how sensory regions represent psychophysical properties (e.g., retinotopy), we propose emotionotopy as a principle of emotion coding
Artificial Intelligence in Materials Science: Applications of Machine Learning to Extraction of Physically Meaningful Information from Atomic Resolution Microscopy Imaging
Materials science is the cornerstone for technological development of the modern world that has been largely shaped by the advances in fabrication of semiconductor materials and devices. However, the Moore’s Law is expected to stop by 2025 due to reaching the limits of traditional transistor scaling. However, the classical approach has shown to be unable to keep up with the needs of materials manufacturing, requiring more than 20 years to move a material from discovery to market. To adapt materials fabrication to the needs of the 21st century, it is necessary to develop methods for much faster processing of experimental data and connecting the results to theory, with feedback flow in both directions. However, state-of-the-art analysis remains selective and manual, prone to human error and unable to handle large quantities of data generated by modern equipment. Recent advances in scanning transmission electron and scanning tunneling microscopies have allowed imaging and manipulation of materials on the atomic level, and these capabilities require development of automated, robust, reproducible methods.Artificial intelligence and machine learning have dealt with similar issues in applications to image and speech recognition, autonomous vehicles, and other projects that are beginning to change the world around us. However, materials science faces significant challenges preventing direct application of the such models without taking physical constraints and domain expertise into account.Atomic resolution imaging can generate data that can lead to better understanding of materials and their properties through using artificial intelligence methods. Machine learning, in particular combinations of deep learning and probabilistic modeling, can learn to recognize physical features in imaging, making this process automated and speeding up characterization. By incorporating the knowledge from theory and simulations with such frameworks, it is possible to create the foundation for the automated atomic scale manufacturing
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