MODIS information, data and control system (MIDACS) operations concepts

The MODIS Information, Data, and Control System (MIDACS) Operations Concepts Document provides a basis for the mutual understanding between the users and the designers of the MIDACS, including the requirements, operating environment, external interfaces, and development plan. In defining the concepts and scope of the system, how the MIDACS will operate as an element of the Earth Observing System (EOS) within the EosDIS environment is described. This version follows an earlier release of a preliminary draft version. The individual operations concepts for planning and scheduling, control and monitoring, data acquisition and processing, calibration and validation, data archive and distribution, and user access do not yet fully represent the requirements of the data system needed to achieve the scientific objectives of the MODIS instruments and science teams. The teams are not yet formed; however, it is possible to develop the operations concepts based on the present concept of EosDIS, the level 1 and level 2 Functional Requirements Documents, and through interviews and meetings with key members of the scientific community. The operations concepts were exercised through the application of representative scenarios

MODIS information, data and control system (MIDACS) level 2 functional requirements

The MODIS Information, Data and Control System (MIDACS) Level 2 Functional Requirements Document establishes the functional requirements for MIDACS and provides a basis for the mutual understanding between the users and the designers of the EosDIS, including the requirements, operating environment, external interfaces, and development plan. In defining the requirements and scope of the system, this document describes how MIDACS will operate as an element of the EOS within the EosDIS environment. This version of the Level 2 Requirements Document follows an earlier release of a preliminary draft version. The sections on functional and performance requirements do not yet fully represent the requirements of the data system needed to achieve the scientific objectives of the MODIS instruments and science teams. Indeed, the team members have not yet been selected and the team has not yet been formed; however, it has been possible to identify many relevant requirements based on the present concept of EosDIS and through interviews and meetings with key members of the scientific community. These requirements have been grouped by functional component of the data system, and by function within each component. These requirements have been merged with the complete set of Level 1 and Level 2 context diagrams, data flow diagrams, and data dictionary

MODIS Information, Data, and Control System (MIDACS) system specifications and conceptual design

The MODIS Information, Data, and Control System (MIDACS) Specifications and Conceptual Design Document discusses system level requirements, the overall operating environment in which requirements must be met, and a breakdown of MIDACS into component subsystems, which include the Instrument Support Terminal, the Instrument Control Center, the Team Member Computing Facility, the Central Data Handling Facility, and the Data Archive and Distribution System. The specifications include sizing estimates for the processing and storage capacities of each data system element, as well as traffic analyses of data flows between the elements internally, and also externally across the data system interfaces. The specifications for the data system, as well as for the individual planning and scheduling, control and monitoring, data acquisition and processing, calibration and validation, and data archive and distribution components, do not yet fully specify the data system in the complete manner needed to achieve the scientific objectives of the MODIS instruments and science teams. The teams have not yet been formed; however, it was possible to develop the specifications and conceptual design based on the present concept of EosDIS, the Level-1 and Level-2 Functional Requirements Documents, the Operations Concept, and through interviews and meetings with key members of the scientific community

A High-Density Linkage Map of the Ancestral Diploid Strawberry, Fragaria iinumae, Constructed with Single Nucleotide Polymorphism Markers from the IStraw90 Array and Genotyping by Sequencing

Fragaria iinumae Makino is recognized as an ancestor of the octoploid strawberry species, which includes the cultivated strawberry, Fragaria ×ananassa Duchesne ex Rozier. Here we report the construction of the first high-density linkage map for F. iinumae. The F. iinumae linkage map (Fii map) is based on two high-throughput techniques of single nucleotide polymorphism (SNP) genotyping: the IStraw90 Array (hereafter “Array”), and genotyping by sequencing (GBS). The F2 generation mapping population was derived by selfing F. iinumae hybrid F1D, the product of a cross between two divergent F. iinumae accessions collected from Hokkaido, Japan. The Fii map consists of seven linkage groups (LGs) and has an overall length of 451.7 cM as defined by 496 loci populated by 4173 markers: 3280 from the Array and 893 from GBS. Comparisons with two versions of the Fragaria vesca ssp. vesca L. ‘Hawaii 4’ pseudo-chromosome (PC) assemblies reveal substantial conservation of synteny and colinearity, yet identified differences that point to possible genomic divergences between F. iinumae and F. vesca, and/or to F. vesca genomic assembly errors. The Fii map provides a basis for anchoring a F. iinumae genome assembly as a prerequisite for constructing a second diploid reference genome for Fragaria

TDRSS Onboard Navigation System (TONS) flight qualification experiment

The National Aeronautics and Space Administration (NASA) Goddard Space Flight Center (GSFC) is currently developing an operational Tracking and Data Relay Satellite (TDRS) System (TDRSS) Onboard Navigation System (TONS) to provide realtime, autonomous, high-accuracy navigation products to users of TDRSS. A TONS experiment was implemented on the Explorer Platform/Extreme Ultraviolet Explorer (EP/EUVE) spacecraft, launched June 7, 1992, to flight qualify the TONS operational system using TDRSS forward-link communications services. This paper provides a detailed evaluation of the flight hardware, an ultrastable oscillator (USO) and Doppler extractor (DE) card in one of the TDRSS user transponders and the ground-based prototype flight software performance, based on the 1 year of TONS experiment operation. The TONS experiment results are used to project the expected performance of the TONS 1 operational system. TONS 1 processes Doppler data derived from scheduled forward-link S-band services using a sequential estimation algorithm enhanced by a sophisticated process noise model to provide onboard orbit and frequency determination and time maintenance. TONS 1 will be the prime navigation system on the Earth Observing System (EOS)-AM1 spacecraft, currently scheduled for launch in 1998. Inflight evaluation of the USO and DE short-term and long-term stability indicates that the performance is excellent. Analysis of the TONS prototype flight software performance indicates that realtime onboard position accuracies of better than 25 meters root-mean-square are achievable with one tracking contact every one to two orbits for the EP/EUVE 525-kilometer altitude, 28.5 degree inclination orbit. The success of the TONS experiment demonstrates the flight readiness of TONS to support the EOS-AM1 mission

A Proposal for A Lean, Fast Mars Round-Trip Mission Architecture: Using Current Technologies for A Human Mission to Mars In The 2030s

We present a lean-minded, fast-transfer mission strategy and architecture concept for a first human mission to Mars that deliberately utilizes a current-technology-favored approach by means of introducing and quantitatively dening two pivotal parameters: 1) an end-to-end Mars mission duration of approximately one year, and 2) a deep space habitat of approximately 4050 metric tons. These parameters are identified and introduced by a 2012 deep space habitat study conducted at the NASA Johnson Space Center (JSC) that focused on a subset of recognized high-engineering-risk factors that may otherwise inhibit or encumber remote space travel to destinations such as Mars or near-Earth asteroids (NEAs). Additional constraints in the study favoring current technology and a lean-minded (very short) surface stay on Mars are shown to offer such Mars mission opportunities in the 2030s, enabled by a combination of on-orbit staging, mission element pre-positioning, and unique round-trip trajectories identied by state-of-the-art astrodynamics algorithms

phot1 inhibition of ABCB19 primes lateral auxin fluxes in the shoot apex required for phototropism

It is well accepted that lateral redistribution of the phytohormone auxin underlies the bending of plant organs towards light. In monocots, photoreception occurs at the shoot tip above the region of differential growth. Despite more than a century of research, it is still unresolved how light regulates auxin distribution and where this occurs in dicots. Here, we establish a system in Arabidopsis thaliana to study hypocotyl phototropism in the absence of developmental events associated with seedling photomorphogenesis. We show that auxin redistribution to the epidermal sites of action occurs at and above the hypocotyl apex, not at the elongation zone. Within this region, we identify the auxin efflux transporter ATP-BINDING CASSETTE B19 (ABCB19) as a substrate target for the photoreceptor kinase PHOTOTROPIN 1 (phot1). Heterologous expression and physiological analyses indicate that phosphorylation of ABCB19 by phot1 inhibits its efflux activity, thereby increasing auxin levels in and above the hypocotyl apex to halt vertical growth and prime lateral fluxes that are subsequently channeled to the elongation zone by PIN-FORMED 3 (PIN3). Together, these results provide new insights into the roles of ABCB19 and PIN3 in establishing phototropic curvatures and demonstrate that the proximity of light perception and differential phototropic growth is conserved in angiosperm

Improved Method for Laser Damage Testing Coated Optics

The damage test procedure for qualifying a coating run of anti-reflection coated optics consists of scanning a pulsed 1064 nm laser over a 1 cm x 1 cm area on a test sample to illuminate approximately 2400 sites. Scans are repeated at 3 J/cm{sup 2} increments until the fluence specification for the optic is reached. In the past, initiation of 1 or more damage sites was classified as a failed coating run, requiring the production optics in the corresponding coating lot be reworked and recoated. Recent laser damage growth tests of 300 repetitive pulses performed on numerous damage sites revealed that all were stable up to 20 J/cm{sup 2}. Therefore the acceptance criteria has been modified to allow a moderate number of damage sites, as long as they are smaller than the allowed dig size and are stable (do not grow). Consequently many coating runs that previously would have been rejected are now accepted, resulting in higher yield, lower cost, and improved delivery schedule. The new test also provides assurance that initiated damage sites are stable during long term operation

Over-expression of Arabidopsis AtCHR23 chromatin remodeling ATPase results in increased variability of growth and gene expression

Background Plants are sessile organisms that deal with their -sometimes adverse- environment in well-regulated ways. Chromatin remodeling involving SWI/SNF2-type ATPases is thought to be an important epigenetic mechanism for the regulation of gene expression in different developmental programs and for integrating these programs with the response to environmental signals. In this study, we report on the role of chromatin remodeling in Arabidopsis with respect to the variability of growth and gene expression in relationship to environmental conditions. Results Already modest (2-fold) over-expression of the AtCHR23 ATPase gene in Arabidopsis results in overall reduced growth compared to the wild-type. Detailed analyses show that in the root, the reduction of growth is due to reduced cell elongation. The reduced-growth phenotype requires sufficient light and is magnified by applying deliberate abiotic (salt, osmotic) stress. In contrast, the knockout mutation of AtCHR23 does not lead to such visible phenotypic effects. In addition, we show that over-expression of AtCHR23 increases the variability of growth in populations of genetically identical plants. These data indicate that accurate and controlled expression of AtCHR23 contributes to the stability or robustness of growth. Detailed RNAseq analyses demonstrate that upon AtCHR23 over-expression also the variation of gene expression is increased in a subset of genes that associate with environmental stress. The larger variation of gene expression is confirmed in individual plants with the help of independent qRT-PCR analysis. Conclusions Over-expression of AtCHR23 gives Arabidopsis a phenotype that is markedly different from the growth arrest phenotype observed upon over-expression of AtCHR12, the paralog of AtCHR23, in response to abiotic stress. This demonstrates functional sub-specialization of highly similar ATPases in Arabidopsis. Over-expression of AtCHR23 increases the variability of growth among genetically identical individuals in a way that is consistent with increased variability of expression of a distinct subset of genes that associate with environmental stress. We propose that ATCHR23-mediated chromatin remodeling is a potential component of a buffer system in plants that protects against environmentally-induced phenotypic and transcriptional variation

Improved Reflectance and Stability of Mo/Si Multilayers

Commercial EUV lithographic systems require multilayers with higher reflectance and better stability then that published to date. Interface-engineered Mo/Si multilayers with 70% reflectance at 13.5 nm wavelength (peak width of 0.545 nm) and 71% at 12.7 nm wavelength (peak width of 0.49 nm) were developed. These results were achieved with 50 bilayers. These new multilayers consist of Mo and Si layers separated by thin boron carbide layers. Depositing boron carbide on interfaces leads to reduction in silicide formation on the Mo-on-Si interfaces. Bilayer contraction is reduced by 30% implying that there is less intermixing of Mo and Si to form silicide. As a result the Mo-on-Si interfaces are sharper in interface-engineered multilayers than in standard Mo/Si multilayers. The optimum boron carbide thicknesses have been determined and appear to be different for Mo-on-Si and Si-on-Mo interfaces. The best results were obtained with 0.4 nm thick boron carbide layer on the Mo-on-Si interface and 0.25 nm thick boron carbide layer on the Si-on-Mo interface. Increase in reflectance is consistent with multilayers with sharper and smoother interfaces. A significant improvement in oxidation resistance of EUV multilayers has been achieved with ruthenium terminated Mo/Si multilayers. The best capping layer design consists of a Ru layer separated from the last Si layer by a boron carbide layer. This design achieves high reflectance and the best oxidation resistance in a water vapor (i.e. oxidation) environment. Electron beam exposures of 4.5 hours in the presence of 5x10{sup -7} torr water vapor partial pressure show no measurable reflectance loss and no increase in the oxide thickness of Ru terminated multilayers. Longer exposures in different environments are necessary to test lifetime stability of many years