We present an overview of protein dynamics based mostly on results of neutron scattering, dielectric relaxation spectroscopy and molecular dynamics simulations. We identify several major classes of ...protein motions on the time scale from faster than picoseconds to several microseconds, and discuss the coupling of these processes to solvent dynamics. Our analysis suggests that the microsecond backbone relaxation process might be the main structural relaxation of the protein that defines its glass transition temperature, while faster processes present some localized secondary relaxations. Based on the overview, we formulate a general picture of protein dynamics and discuss the challenges in this field.
Abstract
Covering faces with masks, due to mandatory pandemic safety regulations, we can no longer rely on the habitual daily-life information. This may be thought-provoking for healthy people, but ...particularly challenging for individuals with neuropsychiatric and neurodevelopmental conditions. Au fait research on reading covered faces reveals that: 1) wearing masks hampers facial affect recognition, though it leaves reliable inferring basic emotional expressions; 2) by buffering facial affect, masks lead to narrowing of emotional spectrum and dampen veridical evaluation of counterparts; 3) masks may affect perceived face attractiveness; 4) covered (either by masks or other veils) faces have a certain signal function introducing perceptual biases and prejudices; 5) reading covered faces is gender- and age-specific, being more challenging for males and more variable even in healthy aging; 6) the hampering effects of masks on social cognition occur over the globe; and 7) reading covered faces is likely to be supported by the large-scale assemblies of the neural circuits far beyond the social brain. Challenges and limitations of ongoing research and parallels to the Reading the Mind in the Eyes Test are assessed. Clarification of how masks affect face reading in the real world, where we deal with dynamic faces and have entrée to additional valuable social signals such as body language, as well as the specificity of neural networks underlying reading covered faces calls for further tailored research.
In this article, we discuss the extension of the Melvin solution for the geon to some models of non-linear electrodynamics with the exact form of the Lagrangian, in particular, for a conformally ...invariant model (CNED), whose Lagrangian depends on the second and fourth order invariants of the electromagnetic field tensor.
Furthermore, absent late positive event-related potential on electroencephalography (EEG) during processing of emotional face expressions in patients with cerebellar stroke indicated the network for ...interpretation of emotional information may be altered after cerebellar damage (Adamaszek et al., 2015). Cerebellar Activation and Connectivity Patterns in Social Cognition A meta-analysis of over 350 functional magnetic resonance imaging (fMRI) studies reported consistent cerebellar activations during different tasks on social cognition, including observation of human motion, mentalizing about intentions in social interactions, inference on personality traits and abstraction (Van Overwalle et al., 2014). Besides its unrivaled potential for fundamental discovery, the causality afforded by cellular neuroscience is very helpful to evaluate hypotheses. In Long-Evans rats, delta band coherence was found between deep cerebellar nuclei and contralateral medial frontal cortex, and muscimol-mediated inactivation of their deep cerebellar nuclei neurons altered interval timing performance.
The cerebellum is believed to play an essential role in a variety of motor and cognitive functions through reciprocal interaction with the cerebral cortex. Recent findings suggest that cerebellar ...involvement in the network specialized for visual body motion processing may be mediated through interaction with the right superior temporal sulcus (STS). Yet, the underlying pattern of structural connectivity between the STS and the cerebellum remains unidentified. In the present work, diffusion tensor imaging analysis on seeds derived from functional magnetic resonance imaging during a task on point-light biological motion perception uncovers a structural pathway between the right posterior STS and the left cerebellar lobule Crus I. The findings suggest existence of a structural loop underpinning bidirectional communication between the STS and cerebellum. This connection might also be of potential value for other visual social abilities.
Unambiguous identification of the superconducting order parameter symmetry in Sr2RuO4 has remained elusive for more than a quarter century. While a chiral p-wave ground state analogue to superfluid ...3He-A was ruled out only very recently, other proposed triplet-pairing scenarios are still viable. Establishing the condensate magnetic susceptibility reveals a sharp distinction between even-parity (singlet) and odd-parity (triplet) pairing since the superconducting condensate is magnetically polarizable only in the latter case. Here field-dependent 17O Knight shift measurements, being sensitive to the spin polarization, are compared to previously reported specific heat measurements for the purpose of distinguishing the condensate contribution from that due to quasiparticles. We conclude that the shift results can be accounted for entirely by the expected field-induced quasiparticle response. An upper bound for the condensate magnetic response of <10% of the normal state susceptibility is sufficient to exclude all purely odd-parity candidates.
Charge transport and structural dynamics in low molecular weight and polymerized 1-vinyl-3-pentylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) are investigated by a combination of ...broadband dielectric spectroscopy, dynamic mechanical spectroscopy and differential scanning calorimetry. While the dc conductivity and fluidity exhibit practically identical temperature dependence for the non-polymerized IL, a significant decoupling of ionic conduction from structural dynamics is observed for the polymerized IL. In addition, the dc conductivity of the polymerized IL exceeds that of its molecular counterpart by four orders of magnitude at their respective calorimetric glass transition temperatures. This is attributed to the unusually high mobility of the anions especially at lower temperatures when the structural dynamics is significantly slowed down. A simple physical explanation of the possible origin of the remarkable decoupling of ionic conductivity from structural dynamics is proposed.
The nature of the transformation by which a supercooled liquid 'freezes' to a glass-the glass transition-is a central issue in condensed matter physics but also affects many other fields, including ...biology. Substantial progress has been made in understanding this phenomenon over the past two decades, yet many key questions remain. In particular, the factors that control the temperature-dependent relaxation and viscous properties of the liquid phase as the glass transition is approached (that is, whether the glass-forming liquid is 'fragile' or 'strong') remain unclear. Here we show that the fragility of a glass-forming liquid is intimately linked to a very basic property of the corresponding glass phase: the relative strength of shear and bulk moduli, or Poisson's ratio.
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