Results 11 to 20 of about 1,354,268 (327)

Differential clock comparisons with a multiplexed optical lattice clock [PDF]

Nature, 2021
Rapid progress in optical atomic clock performance has advanced the frontiers of timekeeping, metrology and quantum science1–3. Despite considerable efforts, the instabilities of most optical clocks remain limited by the local oscillator rather than the ...
Xin Zheng, J. Dolde, V. Lochab, Brett Merriman, Haoran Li, S. Kolkowitz   +5 more
semanticscholar   +1 more source

Demonstration of a trapped-ion atomic clock in space

Nature, 2021
Atomic clocks, which lock the frequency of an oscillator to the extremely stable quantized energy levels of atoms, are essential for navigation applications such as deep space exploration1 and global navigation satellite systems2, and are useful tools ...
E. Burt, J. Prestage, R. Tjoelker, D. Enzer, D. Kuang, D. Murphy, D. Robison, J. Seubert, R. T. Wang, T. Ely   +9 more
semanticscholar   +1 more source

The CODE ambiguity-fixed clock and phase bias analysis products: generation, properties, and performance

Journal of Geodesy, 2021
The generation and use of GNSS analysis products that allow—particularly for the needs of single-receiver applications—precise point positioning with ambiguity resolution (PPP-AR) are becoming more and more popular.
S. Schaer, A. Villiger, D. Arnold, R. Dach, L. Prange, A. Jäggi   +5 more
semanticscholar   +1 more source

The liver-clock coordinates rhythmicity of peripheral tissues in response to feeding

Nature Metabolism, 2021
The mammalian circadian system consists of a central clock in the brain that synchronizes clocks in the peripheral tissues. Although the hierarchy between central and peripheral clocks is established, little is known regarding the specificity and ...
Gal Manella, Elizabeth Sabath, Rona Aviram, Vaishnavi Dandavate, Saar Ezagouri, Marina Golik, Yaarit Adamovich, Gad Asher   +7 more
semanticscholar   +1 more source

Thyroxine differentially modulates the peripheral clock: lessons from the human hair follicle [PDF]

, 2015
The human hair follicle (HF) exhibits peripheral clock activity, with knock-down of clock genes (BMAL1 and PER1) prolonging active hair growth (anagen) and increasing pigmentation.
Farjo, Bessam, Farjo, Nilofer, Hardman, Jonathan A., Haslam, Iain S., Paus, Ralf   +4 more
core   +4 more sources

Curriculum sequencing and the acquisition of clock reading skills among Chinese and Flemish children [PDF]

, 2013
The present study reexamines the adoption of clock reading skills in the primary mathematics curriculum. In many Western countries, the mathematics curriculum adopts a number of age-related stages for teaching clock reading skills, that were defined by ...
Burny, Elise, Desoete, Annemie, Valcke, Martin, Van Steenbrugge, Hendrik, Zhao, Ningning   +4 more
core   +2 more sources

CNS involvement and the feasibility of intratecal chemotherapy administration in patients with a nodal form of diffuse large B-cell lymphoma not otherwise specified. Data of prospective study

Терапевтический архив, 2019
Aim of the issue was to determine indications for intratecal chemotherapy drugs administration to prevent relapse of diffuse large B-cell lymphoma (DLBCL) with central nervous system (CNS) involvement. Materials and methods.
A U Magomedova, A E Misyurina, J K Mangasarova, L G Gorenkova, O V Margolin, E A Fastova, S K Kravchenko   +6 more
doaj   +1 more source

Quantitative analysis of regulatory flexibility under changing environmental conditions [PDF]

, 2010
The circadian clock controls 24-h rhythms in many biological processes, allowing appropriate timing of biological rhythms relative to dawn and dusk. Known clock circuits include multiple, interlocked feedback loops.
Adrian W Thomson, Alexandra Pokhilko, Andrew J Millar, David A Rand, Dunlap JC, Ferenc Nagy, Kieron D Edwards, Kirsten Knox, Laszlo Kozma‐Bognar, Ozgur E Akman, Paul E Brown, Peter J Lumsden, Thomas B   +12 more
core   +4 more sources

Architecture for the photonic integration of an optical atomic clock

Optica, 2019
Laboratory optical atomic clocks achieve remarkable accuracy (now counted to 18 digits or more), opening possibilities for exploring fundamental physics and enabling new measurements.
Z. Newman, V. Maurice, T. Drake, J. Stone, T. Briles, D. Spencer, C. Fredrick, Qing Li, D. Westly, B. Ilic, B. Shen, M. Suh, K. Yang, Cort N. Johnson, David M. S. Johnson, L. Hollberg, K. Vahala, K. Srinivasan, S. Diddams, J. Kitching, S. Papp, M. Hummon   +21 more
semanticscholar   +1 more source

JILA SrI optical lattice clock with uncertainty of 2.0×10−18 [PDF]

Metrologia, 2019
We report on an improved systematic evaluation of the JILA SrI optical lattice clock, achieving a nearly identical uncertainty compared to the previous strontium record set by the JILA SrII optical lattice clock at .
T. Bothwell, D. Kedar, E. Oelker, J. Robinson, S. Bromley, W. Tew, Jun Ye, C. Kennedy   +7 more
semanticscholar   +1 more source