Results 31 to 40 of about 239 (207)

Structural insights and therapeutic targets in Acinetobacter baumannii capsule biosynthesis

FEBS Letters, EarlyView.
Hypervirulent KL49 A. baumannii's capsular polysaccharide contains the nonulosonic acid 8‐epi‐Leg5,7Ac2, synthesized by epimerization via ElaA, ElaB, and ElaC. Crystal structures of ElaA, ElaB, and ElaC reveal their role in CMP‐Leg5,7Ac2 synthesis and regioselective C8 epimerization.
Woo Cheol Lee, Junho Jeong, Chae Yeong Lee, Hyunjoon Cho, Man Hwan Oh, Je Chul Lee, Jee‐Young Lee, Yangmee Kim   +7 more
wiley   +1 more source

Energy Dissipation in Strong Collisionless Shocks: The Crucial Role of Ion-to-electron Scale Separation in Particle-in-cell Simulations

The Astrophysical Journal Letters
Energy dissipation in collisionless shocks is a key mechanism in various astrophysical environments. Its nonlinear nature complicates analytical understanding and necessitates particle-in-cell (PIC) simulations. This study examines the impact of reducing
Mohamad Shalaby
doaj   +1 more source

Stellar Bow Shocks in the Northern Arm of the Galactic Center: More Members and Kinematics of the Massive Star Population [PDF]

The Astrophysical Journal, 2005
We present new 2.2 micron diffraction-limited images from the W. M. Keck 10 m and Gemini 8 m telescopes of the cool Galactic Center sources, IRS 1W, 5, 8, 10W, and 21 along with new proper motions for IRS 1W, 10W and 21. These observations were carried out to test the bowshock hypothesis presented by Tanner et al. as an alternative to a very recent (10^
Tanner, A. M., Ghez, A. M., Morris, M., Christou, J. C.   +3 more
openaire   +2 more sources

Conserved binding mode but diverse interfaces of MreC‐PBP2 interactions

FEBS Letters, EarlyView.
The crystal structure of abMreC reveals a conserved two β‐barrel architecture and provides structural insights into its role within the bacterial elongasome. The abMreC–abPBP2 complex model identifies the molecular basis of MreC‐mediated PBP2 recognition, contributing to the regulation of peptidoglycan synthesis.
Hyunseok Jang, Hyo Been Jin, Chang Min Kim, So Yeon Lee, Hyun Ho Park   +4 more
wiley   +1 more source

Strong Bow Shocks: Turbulence and an Exact Self-similar Asymptotic

The Astrophysical Journal
We show that strong bow shocks are turbulent and nonuniversal near the head but asymptote to a universal, steady, self-similar, and analytically solvable flow in the downstream.
Marcus DuPont, Andrei Gruzinov, Andrew MacFadyen   +2 more
doaj   +1 more source

H₂O masers in a jet-driven bow shock: episodic ejection from a massive young stellar object [PDF]

Monthly Notices of the Royal Astronomical Society, 2016
We report the results of VERA multi-epoch VLBI 22 GHz water maser observations of S255IR-SMA1, a massive young stellar object located in the S255 star forming region. By annual parallax the source distance was measured as D = 1.78 +-0.12 kpc and the source systemic motion was (u alpha cos d, u d) = (-0.13 +- 0.20, -0.06 +- 0.27) mas yr-1. Masers appear
Burns, R. A., Handa, T., Nagayama, T., Sunada, K., Omodaka, T.   +4 more
openaire   +2 more sources

Does Long‐Term Lower Extremity Strength Training in Adults With Knee Osteoarthritis and Varus Alignment Reduce Knee Joint Loading During Gait?

Arthritis Care &Research, EarlyView.
Objective We examined whether 18 months of strength training in individuals with knee varus alignment and medial tibiofemoral osteoarthritis (OA) reduced knee joint loads during walking compared to an attention control group. Methods This study was a secondary analysis of a randomized clinical trial that compared the effects of strength training to a ...
Stephen P. Messier, Matthew N. Vigliotti, Paige E. Rice, Brian Pietrosimone, Shannon L. Mihalko, Edward H. Ip, Richard F. Loeser, David J. Hunter, Ali Guermazi, Ryan Hill, Santiago Saldana, Kim L. Bennell, Paul DeVita   +12 more
wiley   +1 more source

The visibility of the Mach disk and the bow shock of a stellar jet

The Astrophysical Journal, 1989
This paper uses a simple model to determine which of the two principal shocks at the end of a stellar jet, the bow shock or the Mach disk, emits more light at H-beta. It is found that the two shocks should have comparable surface brightness provided the jet and ambient medium densities do not differ by more than one to two orders of magnitude, and both
openaire   +1 more source

The Wind beneath My Wings. I. Spectral Types and Multiplicity of the Central Stars Supporting Stellar Bow Shock Nebulae

The Astrophysical Journal Supplement Series, 2020
Abstract Arcuate mid-infrared nebulae known as stellar bow shock nebulae (SBNe) have been previously hypothesized to be supported by the strong stellar winds and/or luminosity of massive early-type stars. We present an optical spectroscopic survey of 84 stars identified from mid-infrared images as candidate SBN-supporting stars.
William T Chick, Henry A. Kobulnicky, Danielle P. Schurhammer, Julian E. Andrews, Matthew S. Povich, Elle R. Buser, Don M. Dixon, Michael J. Lindman, Stephan A. Munari, Grace M. Olivier, Rebecca L. Sorber, Heather N. Wernke   +11 more
openaire   +1 more source

In Situ Micromechanical Study of Bimodal γ′–γ″ Precipitate Assemblies in Ni–Cr–Al–Nb Superalloy

Advanced Engineering Materials, EarlyView.
A Ni–Cr–Al–Nb superalloy with a bimodal γ′–γ″ precipitate distribution is developed. Composite precipitate assemblies form through heterogeneous nucleation, effectively impeding dislocation motion. Micropillar compression reveals high strength at room and elevated temperatures, governed by precipitate shearing, with coupled faulting mechanisms ...
Ujjval Bansal, Tae‐Hyeok Kang, Pyuck‐Pa Choi, Subin Lee, Christoph Kirchlechner   +4 more
wiley   +1 more source