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In the present paper, we investigate the dark energy equation of state using the Gaussian processes analysis method, without confining a particular parametrization. The reconstruction is carried out by adopting the background data including supernova and Hubble parameter, and perturbation data from the growth rate. It suggests that the background and perturbation data both present a hint of dynamical dark energy. However, the perturbation data have a more promising potential to distinguish non-evolution dark energy including the cosmological constant model. We also test the influence of some parameters on the reconstruction. We find that the matter density parameter Ωm0 has a slight effect on the background data reconstruction, but has a notable influence on the perturbation data reconstruction. While the Hubble constant presents a significant influence on the reconstruction from background data.

•  Introduction •  Free radical scavenging ‐  Scavenging superoxide and other ROS ‐  Scavenging hydroxyl radical and other ROS ‐  Stable radical scavenging •  Metal ion (Fe2+, Fe3+, Cu2+ and Cu+) chelating •  Inhibition of free radical generating enzymes •  Activation of internal antioxidant enzymes •  Prevention of lipid peroxidation •  Prevention of DNA damage •  Prevention of protein modification •  Conclusions Free radicals derived from oxygen, nitrogen and sulphur molecules in the biological system are highly active to react with other molecules due to their unpaired electrons. These radicals are important part of groups of molecules called reactive oxygen/nitrogen species (ROS/RNS), which are produced during cellular metabolism and functional activities and have important roles in cell signalling, apoptosis, gene expression and ion transportation. However, excessive ROS attack bases in nucleic acids, amino acid side chains in proteins and double bonds in unsaturated fatty acids, and cause oxidative stress, which can damage DNA, RNA, proteins and lipids resulting in an increased risk for cardiovascular disease, cancer, autism and other diseases. Intracellular antioxidant enzymes and intake of dietary antioxidants may help to maintain an adequate antioxidant status in the body. In the past decades, new molecular techniques, cell cultures and animal models have been established to study the effects and mechanisms of antioxidants on ROS. The chemical and molecular approaches have been used to study the mechanism and kinetics of antioxidants and to identify new potent antioxidants. Antioxidants can decrease the oxidative damage directly via reacting with free radicals or indirectly by inhibiting the activity or expression of free radical generating enzymes or enhancing the activity or expression of intracellular antioxidant enzymes. The new chemical and cell‐free biological system has been applied in dissecting the molecular action of antioxidants. This review focuses on the research approaches that have been used to study oxidative stress and antioxidants in lipid peroxidation, DNA damage, protein modification as well as enzyme activity, with emphasis on the chemical and cell‐free biological system.

A bstract We introduce superdensity operators as a tool for analyzing quantum information in spacetime. Superdensity operators encode spacetime correlation functions in an operator framework, and support a natural generalization of Hilbert space techniques and Dirac’s transformation theory as traditionally applied to standard density operators. Superdensity operators can be measured experimentally, but accessing their full content requires novel procedures. We demonstrate these statements on several examples. The superdensity formalism suggests useful definitions of spacetime entropies and spacetime quantum channels. For example, we show that the von Neumann entropy of a super-density operator is related to a quantum generalization of the Kolmogorov-Sinai entropy, and compute this for a many-body system. We also suggest experimental protocols for measuring spacetime entropies.

Major depressive disorder is a devastating psychiatric disease that afflicts up to 17% of the world’s population. Postmortem brain analyses and imaging studies of patients with depression have implicated basal lateral amygdala (BLA) dysfunction in the pathophysiology of depression. However, the circuit and molecular mechanisms through which BLA neurons modulate depressive behavior are largely uncharacterized. Here, in mice, we identified that BLA cholecystokinin (CCK) glutamatergic neurons mediated negative reinforcement via D2 medium spiny neurons (MSNs) in the nucleus accumbens (NAc) and that chronic social defeat selectively potentiated excitatory transmission of the CCKBLA–D2NAc circuit in susceptible mice via reduction of presynaptic cannabinoid type-1 receptor (CB1R). Knockdown of CB1R in the CCKBLA–D2NAc circuit elevated synaptic activity and promoted stress susceptibility. Notably, selective inhibition of the CCKBLA–D2NAc circuit or administration of synthetic cannabinoids in the NAc was sufficient to produce antidepressant-like effects. Overall, our studies reveal the circuit and molecular mechanisms of depression.Activating cannabinoid receptors in a newly identified neural circuit ameliorates depressive-like behaviors in mice.

Autism spectrum disorder (ASD) is a common neurodevelopmental disorder. The mechanisms underlying ASD are unclear. Astrocyte alterations are noted in ASD patients and animal models. However, whether astrocyte dysfunction is causal or consequential to ASD-like phenotypes in mice is unresolved. Type 2 inositol 1,4,5-trisphosphate 6 receptors (IP3R2)-mediated Ca 2+ release from intracellular Ca 2+ stores results in the activation of astrocytes. Mutations of the IP3R2 gene are associated with ASD. Here, we show that both IP3R2-null mutant mice and astrocyte-specific IP3R2 conditional knockout mice display ASD-like behaviors, such as atypical social interaction and repetitive behavior. Furthermore, we show that astrocyte-derived ATP modulates ASD-like behavior through the P2X2 receptors in the prefrontal cortex and possibly through GABAergic synaptic transmission. These findings identify astrocyte-derived ATP as a potential molecular player in the pathophysiology of ASD. Astrocytes contribute to autism spectrum disorder (ASD) pathophysiology. Here, the authors show that IP3R2 conditional KO mice show ASD-like behaviours and identify astrocyte-derived ATP as a modulator of these behaviours in mice.