Current Location:home > Browse

1. chinaXiv:201605.01379 [pdf]

A spontaneous depressive pattern in adult female rhesus macaques

Qin, Dongdong; Rizak, Joshua; Chu, Xunxun; Li, Zhifei; Yang, Shangchuan; Feng, Xiaoli; Hu, Xintian; Qin, Dongdong; Rizak, Joshua; Chu, Xunxun; Li, Zhifei; Yang, Shangchuan; Feng, Xiaoli; Hu, Xintian; Qin, Dongdong; Chen, Lin; Lu, Longbao; Hu, Xintian; Yang, Lichuan; Yang, Lichuan
Subjects: Biology >> Biophysics

Non-human primates offer unique opportunities to study the development of depression rooted in behavioral and physiological abnormalities. This study observed adult female rhesus macaques within social hierarchies and aimed to characterize the physiological and brain abnormalities accompanying depressive-like behavior. The behaviors of 31 female rhesus macaques from 14 different breeding groups were video recorded, and the footage was analyzed using the focal animal technique. There were 13 monkeys who never displayed huddling behavior (non-huddlers). The remaining 18 monkeys were divided into two groups according the mean time spent in the huddle posture. Four monkeys were designated as high huddlers, whereas the other 14 monkeys were low huddlers. An inverse relationship was discovered between social rank and depression. High huddlers spent more time engaging in physical contact and in close proximity to other monkeys, as well as less time spontaneously and reactively locomoting, than low huddlers and/or non-huddlers. Cortisol levels measured from the hair were elevated significantly in high huddlers compared with low huddlers and non-huddlers, and the measured cortisol levels were specifically higher in high huddlers than subordinate or dominant control monkeys. Regional cerebral blood flow data revealed significant and widespread decreases in high huddlers compared with non-huddlers.

submitted time 2016-05-12 Hits1666Downloads791 Comment 0

2. chinaXiv:201605.01165 [pdf]

Petrov type I condition and dual fluid dynamics

Cai, Rong-Gen; Li, Li; Yang, Qing; Zhang, Yun-Long
Subjects: Physics >> The Physics of Elementary Particles and Fields

Recently Lysov and Strominger [arXiv:1104.5502] showed that imposing Petrov type I condition on a (p+1)-dimensional time like hypersurface embedded in a (p+2)-dimensional vacuum Einstein gravity reduces the degrees of freedom in the extrinsic curvature of the hypersurface to that of a fluid on the hypersurface, and that the leading-order Einstein constraint equations in terms of the mean curvature of the embedding give the in compressible Navier-Stokes equations of the dual fluid. In this paper we show that the non-relativistic fluid dual to vacuum Einstein gravity does not satisfy the Petrov type I condition at next order, unless additional constraint such as their rotational condition is added. In addition, we show that this procedure can be inversed to derive the non-relativistic hydrodynamics with higher order corrections through imposing the Petrov type I condition, and that some second order transport coefficients can be extracted, but the dual "Petrov type I fluid" does not match the dual fluid constructed from the geometry of vacuum Einstein gravity in the non-relativistic limit. We discuss the procedure both on the finite cut off surface via the non-relativistic hydrodynamic expansion and on the highly accelerated surface via the near horizon expansion.

submitted time 2016-05-09 Hits1677Downloads905 Comment 0

  [1 Pages/ 2 Totals]