Results 41 to 50 of about 35,902 (340)

Jets in Quasi-stellar Objects [PDF]

open access: yesNature, 1968
McCREA1 has raised the interesting possibility that the line spectrum from quasi-stellar objects could arise from a jet aimed toward the observer. McCrea states that this sort of model avoids the intergalactic absorption of Lyman α from 3C9 predicted by Gunn and Peterson2 if the density of neutral intergalactic hydrogen at z = 2 is of the order of 10 ...
openaire   +1 more source

Acoustic Measures Capture Speech Dysfunction in Spinocerebellar Ataxia

open access: yesAnnals of Clinical and Translational Neurology, EarlyView.
ABSTRACT Objective Spinocerebellar ataxias (SCA) are hereditary cerebellar degenerative disorders with a common feature of dysarthria, involving impaired phonatory and articulatory control of speech, thereby affecting social communication. In this study, we investigated whether acoustic measures could objectively measure speech dysfunction and identify
Zena Fadel   +5 more
wiley   +1 more source

Discovery of a Collimated Jet from the Low-luminosity Protostar IRAS 16253−2429 in a Quiescent Accretion Phase with the JWST

open access: yesThe Astrophysical Journal Letters
Investigating Protostellar Accretion (IPA) is a JWST Cycle 1 GO program that uses NIRSpec integral field units and MIRI Medium Resolution Spectrograph to obtain 2.9–28 μ m spectral cubes of young, deeply embedded protostars with luminosities of 0.2–10 ...
Mayank Narang   +38 more
doaj   +1 more source

Time-variable Jet Ejections from RW Aur A, RY Tau, and DG Tau

open access: yesThe Astrophysical Journal Supplement Series, 2022
We present Gemini-NIFS, Very Large Telescope-SINFONI, and Keck-OSIRIS observations of near-IR [Fe ii ] emission that are associated with well-studied jets from three active T Tauri stars—RW Aur A, RY Tau, and DG Tau—taken from 2012 to 2021.
Michihiro Takami   +19 more
doaj   +1 more source

Associations of Sleep and Shift Work with Osteoarthritis Risk

open access: yesArthritis Care &Research, Accepted Article.
Objective Daily rhythms may be critical for maintaining homeostasis of joint tissues. We aimed to investigate the relationships between circadian clock disruption, sleep, and osteoarthritis (OA) risk in humans. Methods In the UK Biobank, a prospective 500,000‐person cohort, we evaluated associations between sleep duration, sleeplessness/insomnia, and ...
Elizabeth L. Yanik   +5 more
wiley   +1 more source

A Q‐Learning Algorithm to Solve the Two‐Player Zero‐Sum Game Problem for Nonlinear Systems

open access: yesInternational Journal of Adaptive Control and Signal Processing, Volume 39, Issue 3, Page 566-581, March 2025.
A Q‐learning algorithm to solve the two‐player zero‐sum game problem for nonlinear systems. ABSTRACT This paper deals with the two‐player zero‐sum game problem, which is a bounded L2$$ {L}_2 $$‐gain robust control problem. Finding an analytical solution to the complex Hamilton‐Jacobi‐Issacs (HJI) equation is a challenging task.
Afreen Islam   +2 more
wiley   +1 more source

Discovery of synchrotron emission from a YSO jet

open access: yesEPJ Web of Conferences, 2013
Synchrotron emission at radio wavelengths is commonly found in relativistic jets from active galactic nuclei (AGNs) and microquasars and allows the study of the magnetic field in these kind of jets.
Carrasco-González Carlos   +5 more
doaj   +1 more source

Simulated images of stellar jets

open access: yesThe Astronomical Journal, 1991
In many cases, the sources of jetlike Herbig-Haro objects are optically invisible, embedded objects which are usually detected at infrared wavelengths. The jets become visible only at distance of 10 16 -10 17 cm from the source, where they emerge from the molecular cloud core that surrounds the central object.
Hume A. Feldman, A. C. Raga
openaire   +1 more source

Variable stellar jets -- II. Precessing jets and stagnation knots [PDF]

open access: yesMonthly Notices of the Royal Astronomical Society, 2001
We investigate, from both analytical and numerical points of view, the formation of stagnation features in precessing Herbig–Haro type jets. These structures are formed via a mechanism very similar to that recently presented as a formation mechanism for fast low-ionization emission regions (FLIERs) in planetary nebulae.
openaire   +1 more source

An Adaptive Human Pilot Model With Reaction Time Delay for Enhanced Adaptive Control in Piloted Systems

open access: yesInternational Journal of Adaptive Control and Signal Processing, EarlyView.
This work introduces an adaptive human pilot model that captures pilot time‐delay effects in adaptive control systems. The model enables the prediction of pilot–controller interactions, facilitating safer integration and improved design of adaptive controllers for piloted applications.
Abdullah Habboush, Yildiray Yildiz
wiley   +1 more source

Home - About - Disclaimer - Privacy