446 research outputs found
Environmental Change and Sustainability of Indigenous Languages in Northern Alaska
Relatively few people under the age of 60 are fluent speakers of the various Indigenous languages of Alaska. Concurrently, climate change is severely impacting Alaska and its residents, where environments are changing far more rapidly than the majority of the planet. These factors complicate the land-language nexus and may have implications for the sustainability of Indigenous languages in Alaska and other parts of the Arctic. In this collaborative, community-centered project, we spoke with Iñupiaq and Yupik language speakers to learn how rapid environmental change affects heritage language discourse practices and how generational gaps in levels of heritage language fluency affect safety and efficacy of customary and traditional land use activities. The results show how local community choices and attitudes are reflecting and constructing dynamic ecologies of language, culture, and environment. Iñupiaq and Yupik languages provide important forms of socio-cultural resilience because they embed the past, yet are inherently dynamic. Community-driven social practices that promote increased local heritage language use can lead to new, creative language domains, new expressions of Indigenous culture, and new Indigenous stances toward a changing environment.
Relativement peu de personnes de moins de 60 ans parlent les diverses langues autochtones de l’Alaska couramment. En même temps, le changement climatique a de fortes incidences sur l’Alaska et ses habitants, où l’environnement change beaucoup plus vite que dans la majorité de la planète. Ces facteurs compliquent le lien entre la terre et la langue, sans compter qu’ils peuvent avoir des répercussions sur la durabilité des langues autochtones en Alaska et dans d’autres régions de l’Arctique. Dans le cadre de ce projet collaboratif axé sur la communauté, nous nous sommes entretenus avec des locuteurs parlant les langues des Iñupiaq et des Yupik afin d’apprendre comment les changements environnementaux rapides influencent les pratiques linguistiques patrimoniales et comment les écarts générationnels en ce qui a trait aux degrés de facilité verbale des langues du patrimoine influent sur la sécurité et l’efficacité des activités habituelles et traditionnelles liées à l’utilisation de la terre. Les résultats de l’étude illustrent comment les choix et les attitudes des gens de la région sont le reflet d’écologies dynamiques en matière de langue, de culture et d’environnement, et comment ils parviennent à former ces écologies. Les langues des Iñupiaq et des Yupik fournissent d’importantes formes de résilience socioculturelle parce qu’elles incorporent le passé tout en étant intrinsèquement dynamiques. Les pratiques sociales communautaires favorisant une utilisation accrue des langues du patrimoine local peuvent finir par engendrer de nouveaux domaines linguistiques créatifs, de nouvelles expressions de la culture autochtone et de nouvelles positions autochtones à l’égard de l’environnement changeant
The Age of Cluster Galaxies from Continuum Colors
We determine the age of 1,104 early-type galaxies in eight rich clusters ( to ) using a new continuum color technique. We find that
galaxies in clusters divide into two populations, an old population with a mean
age similar to the age of the Universe (12 Gyrs) and a younger population with
a mean age of 9 Gyrs. The older population follows the expected relations for
mass and metallicity that imply a classic monolithic collapse origin. Although
total galaxy metallicity is correlated with galaxy mass, it is uncorrelated
with age. It is impossible, with the current data, to distinguish between a
later epoch of star formation, longer duration of star formation or late bursts
of star formation to explain the difference between the old and young
populations. However, the global properties of this younger population are
correlated with cluster environmental factors, which implies secondary
processes, post-formation epoch, operate on the internal stellar population of
a significant fraction of cluster galaxies. In addition, the mean age of the
oldest galaxies in a cluster are correlated with cluster velocity dispersion
implying that galaxy formation in massive clusters begins at earlier epochs
than less massive clusters.Comment: 35 pages, 10 figures, accepted by Ap
Advances in Measuring the Apparent Optical Properties (AOPs) of Optically Complex Waters
This report documents new technology used to measure the apparent optical properties (AOPs) of optically complex waters. The principal objective is to be prepared for the launch of next-generation ocean color satellites with the most capable commercial off-the-shelf (COTS) instrumentation. An enhanced COTS radiometer was the starting point for designing and testing the new sensors. The follow-on steps were to apply the lessons learned towards a new in-water profiler based on a kite-shaped backplane for mounting the light sensors. The next level of sophistication involved evaluating new radiometers emerging from a development activity based on so-called microradiometers. The exploitation of microradiometers resulted in an in-water profiling system, which includes a sensor networking capability to control ancillary sensors like a shadowband or global positioning system (GPS) device. A principal advantage of microradiometers is their flexibility in producing, interconnecting, and maintaining instruments. The full problem set for collecting sea-truth data--whether in coastal waters or the open ocean-- involves other aspects of data collection that were improved for instruments measuring both AOPs and inherent optical properties (IOPs), if the uncertainty budget is to be minimized. New capabilities associated with deploying solar references were developed as well as a compact solution for recovering in-water instrument systems from small boats
Advances in Above- and In-Water Radiometry, Volume 3: Hybridspectral Next-Generation Optical Instruments
This publication documents the scientific advances associated with new instrument systems and accessories built to improve above- and in-water observations of the apparent optical properties (AOPs) for a diversity of water masses, including optically complex waters. The principal objective is to be prepared for the launch of next-generation ocean color satellites with the most capable commercial off-the-shelf (COTS) instrumentation in the shortest time possible. The technologies described herein are entirely new hybrid sampling capabilities, so as to satisfy the requirements established for next-generation missions. Both above- and in-water instruments are documented with software options for autonomous control of data collection activities as applicable. The instruments were developed for the Hybridspectral Alternative for Remote Profiling of Optical Observations for NASA Satellites (HARPOONS) vicarious calibration project. The state-of-the-art accuracy required for vicarious calibration also led to the development of laboratory instruments to ensure the field observations were within uncertainty requirements. Separate detailed presentations of the individual instruments provide the hardware designs, accompanying software for data acquisition and processing, and examples of the results achieved
Advances in Above- and In-Water Radiometry, Volume 2: Autonomous Atmospheric and Oceanic Observing Systems
This publication documents the scientific advances associated with new instrument systems and accessories built to improve above- and in-water observations of the apparent optical properties (AOPs) of optically complex waters. The principal objective is to be prepared for the launch of next-generation ocean color satellites with the most capable commercial off-the-shelf (COTS) instrumentation in the shortest time possible. The Hybridspectral Alternative for Remote Profiling of Optical Observations for NASA Satellites (HARPOONS) is presented as a case example of technologies conceived, developed, and deployed operationally in support of next-generation mission requirements. The field trials, field commissioning, and operational demonstration resulted in a technology readiness level (TRL) value of 9 for a diversity of laboratory and field instrument systems. Separate detailed presentations of the individual instruments provide the hardware designs, accompanying software for data acquisition and processing, and examples of the results achieved. For the laboratory components, calibration and characterization procedures are described along with an estimation of the sources of uncertainty, which culminates in a full uncertainty budget for the radiometers deployed to the field
Advances in Above- and In-Water Radiometry, Volume 1: Enhanced Legacy and State-of-the-Art Instrument Suites
This publication documents the scientific advances associated with new instrument systems and accessories built to improve above- and in-water observations of the apparent optical properties (AOPs) of aquatic ecosystems. The perspective is to obtain high quality data in offshore, nearshore, and inland waters with equal efficacy. The principal objective is to be prepared for the launch of the next-generation ocean color satellites with the most capable commercial off-the-shelf (COTS) instrumentation in the shortest time possible. The technologies described herein are designed to either improve legacy radiometric systems or to provide entirely new hybrid sampling capabilities, so as to satisfy the requirements established for diverse remote sensing requirements. Both above- and in-water instrument suites are documented with software options for autonomous control of data collection activities. The latter includes an airborne instrument system plus unmanned surface vessel (USV) and buoy concepts
Synapse-associated protein 102/dlgh3 couples the NMDA receptor to specific plasticity pathways and learning strategies
Understanding the mechanisms whereby information encoded within patterns of action potentials is deciphered by neurons is central to cognitive psychology. The multiprotein complexes formed by NMDA receptors linked to synaptic membrane-associated guanylate kinase (MAGUK) proteins including synapse-associated protein 102 (SAP102) and other associated proteins are instrumental in these processes. Although humans with mutations in SAP102 show mental retardation, the physiological and biochemical mechanisms involved are unknown. Using SAP102 knock-out mice, we found specific impairments in synaptic plasticity induced by selective frequencies of stimulation that also required extracellular signal-regulated kinase signaling. This was paralleled by inflexibility and impairment in spatial learning. Improvement in spatial learning performance occurred with extra training despite continued use of a suboptimal search strategy, and, in a separate nonspatial task, the mutants again deployed a different strategy. Double-mutant analysis of postsynaptic density-95 and SAP102 mutants indicate overlapping and specific functions of the two MAGUKs. These in vivo data support the model that specific MAGUK proteins couple the NMDA receptor to distinct downstream signaling pathways. This provides a mechanism for discriminating patterns of synaptic activity that lead to long-lasting changes in synaptic strength as well as distinct aspects of cognition in the mammalian nervous system
Genotype analysis of polymorphisms in autoimmune susceptibility genes, CTLA-4 and PTPN22, in an acute anterior uveitis cohort
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