Results 31 to 40 of about 623,086 (230)

Limitations in Testing the Lense–Thirring Effect with LAGEOS and the Newly Launched Geodetic Satellite LARES 2

open access: yesUniverse, 2023
The new geodetic satellite LARES 2, cousin of LAGEOS and sharing with it almost the same orbital parameters apart from the inclination, displaced by 180 deg, was launched last year. Its proponents suggest using the sum of the nodes of LAGEOS and of LARES
Lorenzo Iorio
doaj   +1 more source

GPS Satellites Orbits: Resonance [PDF]

open access: yesMathematical Problems in Engineering, 2009
The effects of perturbations due to resonant geopotential harmonics on the semimajor axis of GPS satellites are analyzed. For some GPS satellites, secular perturbations of about 4 m/day can be obtained by numerical integration of the Lagrange planetary equations considering in the disturbing potential the main secular resonant coefficients.
Damasceno Ferreira, Luiz Danilo   +1 more
openaire   +3 more sources

Orbital Debris and the Market for Satellites

open access: yesSSRN Electronic Journal, 2022
This paper studies the economic consequences of orbital debris for commercial outer-space activities. Spacecraft launches and other outer-space human activities produce pollution (i.e., orbital debris), which represent a hazardous negative externality increasing the risk of collision and the destruction of satellites.
Anelí Bongers, José L. Torres
openaire   +3 more sources

A Smart Realtime Service to Broadcast the Precise Orbits of GPS Satellite and Its Performance on Precise Point Positioning

open access: yesSensors, 2020
At present, Global Position System (GPS) navigation ephemeris mainly broadcasts satellite orbits with meter-level precision for standard point positioning and precise relative positioning. With the rapid development of real-time precise point positioning
Dehai Li   +5 more
doaj   +1 more source

Chiral separation of chloroalkanes with the chromatographic column onboard Martian rovers

open access: yesFEBS 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

Loss of proton‐sensing TDAG8 increases tumor progression in mouse models of colon cancer

open access: yesMolecular Oncology, EarlyView.
Loss of the pH‐sensing receptor TDAG8 accelerates colorectal cancer progression in mice. Animals lacking TDAG8 expression had increased tumor growth, DNA damage, and recruitment of tumor‐associated immune cells, including macrophages, neutrophils, and monocytes.
Ermanno Malagola   +11 more
wiley   +1 more source

Asymptotic analysis of displaced lunar orbits [PDF]

open access: yes, 2009
The design of spacecraft trajectories is a crucial task in space mission design. Solar sail technology appears as a promising form of advanced spacecraft propulsion which can enable exciting new space science mission concepts such as solar system ...
Simo, Jules, McInnes, Colin R.
core   +4 more sources

In vitro and in silico modelling of ROS1‐positive non‐small cell lung cancer reveals fusion‐dependent tyrosine kinase inhibitor responses

open access: yesMolecular Oncology, EarlyView.
Drug resistance limits treatment success in a subset of lung cancers driven by ROS1 gene alterations. Using patient‐derived cells and computer simulations, we studied three key mutations and how they affect five targeted drugs. The mutations reduced drug effectiveness in different ways by altering protein structure and behavior.
Farhan Ul Haq   +8 more
wiley   +1 more source

Delivery of DNA‐encoded vaccines and proteins in mice using cutaneous suction‐mediated transfection

open access: yesFEBS Open Bio, EarlyView.
Cutaneous suction‐mediated transfection in mice for delivery of DNA‐encoded vaccines and proteins. A critical limitation of DNA vaccines and other therapeutics is transfection in vivo to produce the encoded antigens or therapeutic proteins. Cutaneous suction‐based methods have demonstrated effectiveness in many animal models and have been successfully ...
Emran O. Lallow   +12 more
wiley   +1 more source

Improved Simulated Annealing Algorithm on the Design of Satellite Orbits for Common-View Laser Time Transfer

open access: yesRemote Sensing
Laser Time Transfer (LTT) has proven to be able to improve remote time transfer accuracy compared to microwave technology. The impact of satellite clock errors and atmospheric delays during LTT will be further reduced in the common-view mode.
Han Xue   +5 more
doaj   +1 more source

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