Topographic Data and Satellite Spectral Response in Subarctic High-Relief Terrain Analysis

Satellite images and digital evaluation models were analyzed to interpret and quantify vegetation communities and active geomorphic surfaces in a mountainous area in southwest Yukon, Canada. High levels of discrimination were determined for the digital satellite and terrain data when compared to field studies and aerial photo interpretation of basic biophysical units, specific vegetation cover types and geomorphic process categories. The agreement between field identification of a site and discriminant analysis of that site using the digital data as discriminating variables ranged from 60 to 85% and contained improvements of up to 20% when topographic data such as slope angle and incidence value or aspect were added to spectral discriminant functions. Active geomorphic surfaces were grouped successfully into process categories such as landslides, debris flows, solifluction and talus sorting. Visual interpretation of the changes in the landscape detected using Landsat Thematic Mapper imagery from 1985 and SPOT HRV MLA imagery in 1989 were attributed to (1) running water in the alluvial deposits and organic terrain, (2) different water levels in the river, delta and floodplain, and (3) a general trend of class change from wet to dry throughout the study area. This latter change may be a result of imaging the same class (e.g., alpine tundra) under more senescent (i.e., brown) conditions and may be explained with reference to a warming/drying trend in the intervening years.Key words: satellite imagery, digital elevation models, change detectionMots clés: images satellites, modèles d’élévation numériques, détection des changement

A study of graphite morphology control in cast iron

The objectives of the research project were to gain a deeper understanding of the factors influencing the graphite morphology in cast iron; particularly the role of different solute elements in relation to the industrial manufacture of compacted graphite iron. A number of melt treatment processes were assessed for their abilities to produce low nodularity compacted graphite microstructures over a range of casting section thicknesses. In this respect, the magnesium-titanium method was found to be superior to treatment using cerium Mischmetall and calcium additives; and very promising results were obtained with methods using zirconium as a major constituent of the treatment alloy. Scanning electron microscopy, secondary ion mass spectrometry and X-ray microanalysis were used to study the structural characteristics of different cast iron microstructures and the elemental distributions of important solutes between the phases. This information was used to clarify the role of the main solute elements in graphite morphology control and to assess current graphite growth theories

Remote Sensing of Ecology, Biodiversity and Conservation: A Review from the Perspective of Remote Sensing Specialists

Remote sensing, the science of obtaining information via noncontact recording, has swept the fields of ecology, biodiversity and conservation (EBC). Several quality review papers have contributed to this field. However, these papers often discuss the issues from the standpoint of an ecologist or a biodiversity specialist. This review focuses on the spaceborne remote sensing of EBC from the perspective of remote sensing specialists, i.e., it is organized in the context of state-of-the-art remote sensing technology, including instruments and techniques. Herein, the instruments to be discussed consist of high spatial resolution, hyperspectral, thermal infrared, small-satellite constellation, and LIDAR sensors; and the techniques refer to image classification, vegetation index (VI), inversion algorithm, data fusion, and the integration of remote sensing (RS) and geographic information system (GIS)

Global water cycle

This research is the MSFC component of a joint MSFC/Pennsylvania State University Eos Interdisciplinary Investigation on the global water cycle extension across the earth sciences. The primary long-term objective of this investigation is to determine the scope and interactions of the global water cycle with all components of the Earth system and to understand how it stimulates and regulates change on both global and regional scales. Significant accomplishments in the past year are presented and include the following: (1) water vapor variability; (2) multi-phase water analysis; (3) global modeling; and (4) optimal precipitation and stream flow analysis and hydrologic processes

Thermoplastic nanofluidic devices for biomedical applications

This review presents an overview of recent advancements in the fabrication, surface modification and applications of thermoplastic nanofluidic devices

Outcomes of Early Endoscopic Realignment Versus Suprapubic Cystostomy and Delayed Urethroplasty for Pelvic Fracture-related Posterior Urethral Injuries : A Systematic Review

Peer reviewedPostprin

Actin depolymerization is sufficient to induce programmed cell death in self-incompatible pollen

Self-incompatibility (SI) prevents inbreeding through specific recognition and rejection of incompatible pollen. In incompatible Papaver rhoeas pollen, SI triggers a Ca2+ signaling cascade, resulting in the inhibition of tip growth, actin depolymerization, and programmed cell death (PCD). We investigated whether actin dynamics were implicated in regulating PCD. Using the actin-stabilizing and depolymerizing drugs jasplakinolide (Jasp) and latrunculin B, we demonstrate that changes in actin filament levels or dynamics play a functional role in initiating PCD in P. rhoeas pollen, triggering a caspase-3–like activity. Significantly, SI-induced PCD in incompatible pollen was alleviated by pretreatment with Jasp. This represents the first account of a specific causal link between actin polymerization status and initiation of PCD in a plant cell and significantly advances our understanding of the mechanisms involved in SI

The MethaneSAT Mission

The MethaneSAT mission is expected to launch in Q4 of 2022 with a primary goal of providing systematic monitoring of methane emissions from regions accounting for more than 80% of global oil and gas production. High precision measurements from the sensor will allow quantification and mapping of essentially all methane emissions from these regions and identify the location of major point sources and quantify those methane emissions. MethaneSAT has a wide observing swath (~200km), high spatial resolution (~100m x400m), low detection threshold (~2pbb @ 1.5 km2), and targeting capability up to 40° off nadir, enabling it to fill a critical data and observing gap in obtaining quantitative measurements of methane emissions that can be detected by current and planned satellites that either focus on point sources or map the globe. MethaneSAT data will be publicly available and will provide companies, countries and the civil society at-large, the capability to quantify total methane emissions over time and map where they occur, resulting in improved capacity to manage, and reduce those emissions. The science and policy objectives were used to derive the mission architecture that consists of a single space craft in a sun-synchronous low-Earth orbit with agility to meet the frequent site revisit requirements through off-nadir pointing. MethaneSAT consists of two spectrometers, one covering 1249 – 1305nm wavelengths for Oxygen detection and one covering 1605 –1683 nm wavelengths for Methane and Carbon Dioxide retrievals, with 0.1 nm spectral sampling and 0.3 nm spectral resolution. MethaneSAT strongly leverages Ball Aerospace’s heritage designs and spectrometer technologies developed for Landsat, Ozone Mapping & Profiler Suite (OMPS), and the Tropospheric Emissions: Monitoring Pollution (TEMPO)/Geostationary Environmental Monitoring Spectrometer (GEMS) instruments, with new designs developed a s necessary to meet mission needs. MethaneSAT is packaged into a SmallSat and will launch as a secondary payload on a Falcon 9 rocket

Benthic Habitat Mapping in the Tortugas Region, Florida

Concern about declining trends in coral reef habitats and reef fish stocks in the Florida Keys contributed to the implementation of a network of no-take marine protected areas in 1997. In support of the efforts of the Dry Tortugas National Park and Florida Keys National Marine Sanctuary to implement additional no-take areas in the Tortugas region in 2001, we expanded the scale of our fisheries independent monitoring program for coral reef fishes in the region. To provide a foundation for the habitat-based, stratified random sampling design of the program, we created a digital benthic habitat map of coral reef and hard-bottom habitats in a geographic information system by synthesizing data from bathymetric surveys, side-scan sonar imagery, aerial photogrammetry, existing habitat maps, and in situ visual surveys. Existing habitat maps prior to 1999 were limited to shallow-water (\u3c 20 m depth) soft-sediment, coral reef, and hard-bottom habitats within Dry Tortugas National Park and did not include deeper areas such as the Tortugas Bank, now partially contained within no-take marine protected area boundaries. From diver observations made during the 1999 survey, we developed a classification scheme based on habitat relief and patchiness to describe nine hard-bottom and coral reef habitats encountered from 1-33 m depth. We provide estimates of area by habitat type for no-take marine protected areas in the Tortugas region. Updated information on the spatial distribution and characteristics of benthic habitats will be used to guide future monitoring, assessment, and management activities in the region. Significant data gaps still exist for the western area of the Florida Keys National Marine Sanctuary and are a priority for future research

Proteostatic Control of Telomerase Function through TRiC-Mediated Folding of TCAB1

SummaryTelomere maintenance by telomerase is impaired in the stem cell disease dyskeratosis congenita and during human aging. Telomerase depends upon a complex pathway for enzyme assembly, localization in Cajal bodies, and association with telomeres. Here, we identify the chaperonin CCT/TRiC as a critical regulator of telomerase trafficking using a high-content genome-wide siRNA screen in human cells for factors required for Cajal body localization. We find that TRiC is required for folding the telomerase cofactor TCAB1, which controls trafficking of telomerase and small Cajal body RNAs (scaRNAs). Depletion of TRiC causes loss of TCAB1 protein, mislocalization of telomerase and scaRNAs to nucleoli, and failure of telomere elongation. DC patient-derived mutations in TCAB1 impair folding by TRiC, disrupting telomerase function and leading to severe disease. Our findings establish a critical role for TRiC-mediated protein folding in the telomerase pathway and link proteostasis, telomere maintenance, and human disease