474 research outputs found
DIETARY COGNITIVE TENDENCY, MENTAL HEALTH ABILITY AND FUNCTIONAL RISK OF THE ELDERLY IN GUANGXI: A CROSS-SECTIONAL STUDY
DIETARY COGNITIVE TENDENCY, MENTAL HEALTH ABILITY AND FUNCTIONAL RISK OF THE ELDERLY IN GUANGXI: A CROSS-SECTIONAL STUDY
Stochastic Linear-quadratic Control Problems with Affine Constraints
In this paper, we investigate the stochastic linear-quadratic control
problems with affine constraints in random coefficients case. With the help of
the Pontryagin maximum principle and stochastic Riccati equation, the dual
problem of original problem is established and the feedback solution of the
optimal control problem is obtained. Under the Slater condition, the
equivalence is proved between the solutions to the original problem and the
ones of the dual problem, and the KKT condition is also provided for the dual
problem. Finally, an invertibility assumption is given for ensuring the
uniqueness of the solutions to the dual problem
Widespread Presence of Glycolaldehyde and Ethylene Glycol Around Sagittarius B2
We report the detection of widespread CHOHCHO and HOCHCHOH
emission in Galactic center giant molecular cloud Sagittarius B2 using the
Shanghai Tianma 65m Radio Telescope. Our observations show for the first time
that the spatial distribution of these two important prebiotic molecules
extends over 15 arc-minutes, corresponding to a linear size of approximately 36
pc. These two molecules are not just distributed in or near the hot cores. The
abundance of these two molecules seems to decrease from the cold outer region
to the central region associated with star-formation activity. Results present
here suggest that these two molecules are likely to form through a low
temperature process. Recent theoretical and experimental studies demonstrated
that prebiotic molecules can be efficiently formed in icy grain mantles through
several pathways. However, these complex ice features cannot be directly
observed, and most constraints on the ice compositions come from millimeter
observations of desorbed ice chemistry products. These results, combined with
laboratory studies, strongly support the existence of abundant prebiotic
molecules in ices.Comment: 20 pages, 7 figures, accepted by Ap
(E)-N′-(4-Methoxybenzylidene)benzohydrazide
In the title molecule, C15H14N2O2, the dihedral angle between the benzene rings is 5.93 (17)°. In the crystal, intermolecular N—H⋯O hydrogen bonds link the molecules into chains propagating in [010]
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