Results 91 to 100 of about 2,510,789 (285)
GNSS Satellite Orbit Validation Using Satellite Laser Ranging [PDF]
, 2013 With a total of four new regional and global navigation sa tellite systems that have launched first satellites or even started an operational serv ice, the GNSS landscape has experienced major changes in recent years.
Steigenberger, Peter +2 more
core
FEBS Letters, EarlyView.Mycobacterial 3‐methylcrotonyl‐CoA carboxylase uses a mobile biotin‐carrying domain to shuttle a carboxyl group between two catalytic sites, enabling carboxylation of 3‐methylcrotonyl‐CoA during leucine breakdown. Cryo‐electron microscopy captures the carrier at both sites and reveals an inward loop movement that may prevent futile rebinding to the ...
Ajit Yadav +2 more
wiley +1 more source
Orbit Precision Analysis of Small Man-Made Space Objects in LEO Based on Radar Tracking Measurements [PDF]
, 2012 The German Space Operations Center (GSOC) performs collision avoidance for 11 LEO and 2 GEO satellites. Risk detection and maneuver decisions strongly depend on the computed probability of collision that is driven by the anticipated orbit precision of ...
Letsch, Klemens +6 more
core
GPS Based Reduced-Dynamic Orbit Determination for Low Earth Orbiters with Ambiguity Fixing
International Journal of Aerospace Engineering, 2015 With the ever-increasing number of satellites in Low Earth Orbit (LEO) for scientific missions, the precise determination of the position and velocity of the satellite is a necessity.
Yang Yang, Xiaokui Yue, Jianping Yuan
doaj +1 more source
FEBS Letters, EarlyView.How do genomes gain new functional parts? In eukaryotes, which tend to evolve under weak selection, much of the genome is junk. Palazzo and Qiu borrow the logic of Markov chains to show how non‐functional DNA becomes functional through the appearance of intermediate states, which arise due to epistasis, buffering, and biochemical messiness, allowing ...
Alexander F. Palazzo, Yi Qiu
wiley +1 more source
The Shewanella oneidensis Fic enzyme SoFic targets the switch‐I region of EF‐Tu for AMPylation
FEBS Letters, EarlyView.Fic enzymes mediate diverse post‐translational modifications across all domains of life, including AMPylation. Prokaryotic EF‐Tu can be AMPylated and deAMPylated by the conserved Fic enzyme SoFic. Structural and biochemical approaches were used to characterize the effect of AMPylation on EF‐Tu, SoFic's enzymatic activities, and the enzyme‐target ...
Svenja Runge +6 more
wiley +1 more source
Chiral separation of chloroalkanes with the chromatographic column onboard Martian rovers
FEBS Letters, EarlyView.Computer image of the Rosalind Franklin Rover of ESA's ExoMars mission. ExoMars is scheduled to land on planet Mars in Oxia Planum in 2029. This area represents an interesting spot to look for biosignatures. Investigations of ExoMars include measurement on molecular chirality. We show that chiral chloroalkanes, that have been identified on Mars, can be
Asma Merzougui +4 more
wiley +1 more source
Precise orbit determination of Haiyang-2 using satellite laser ranging
, 2013 With the successful launch and official commissioning of China's first dynamic ocean environment satellite Haiyang-2 (HY-2), China's capabilities for oceanic environment monitoring and oceanic resource detecting have been further improved and enhanced ...
Wu Bin, Zhao Gang, Zhou XuHua
core
Characterizing receiver clock behaviors onboard Low Earth Orbiters: A case study of GRACE satellites
Geodesy and Geodynamics, 2019 Accurate estimation of clocks, for example for the Gravity Recovery And Climate Experiment (GRACE) twin-satellites, is a critical part of precise orbit determination (POD) that ensures temporal gravity inversion. Characterizing the periodic variations of
Tzu-Pang Tseng, C.K. Shum, Ting-Yi Yang
doaj +1 more source
FEBS Letters, EarlyView.Transient oligomers formed by intrinsically disordered proteins may be ‘invisible’ to direct detection yet remain accessible to solution NMR through equilibrium‐exchange measurements and pressure‐jump experiments. Complementary methods report on mass, stoichiometry, selected distance distributions, morphology, and internal packing.
Martin D. Gelenter, Ad Bax
wiley +1 more source