Mesoporous Nitrogen-Doped Holey Reduced Graphene Oxide: Preparation, Purification, and Application for Metal-Free Electrochemical Sensing of Dopamine.

Holey graphenic nanomaterials with porosity within the basal plane attract significant interest. It is observed that the perforation of graphene can enhance the specific surface area of the nanosheet, ensuring effective wetting and penetration of electrolytes to the electrode surface, facilitating rapid charge transfer, and boosting the electrocatalytic efficacy of the transducers. This study reports the first example of nitrogen-doped holey reduced graphene oxide with a mesoporous morphology of the graphene basal plane (N-MHG). It is shown that N-MHG can be synthesized through a one-step hydrothermal treatment of GO using NH3 and H2O2. A straightforward procedure for the purification of N-MHG has also been developed. AFM, TEM, and Raman analyses have revealed that N-MHG possesses a highly mesoporous network structure with a pore size ranging from 10 to 50 nm. X-ray photoelectron spectroscopy data have indicated a partial reduction of the graphene oxide sheets during the etching process but also show a 3-5 times higher content of C═O and O-C═O fragments compared to rGO. This could account for the remarkable stability of the N-MHG aqueous suspension. An electrochemical sensor for dopamine analysis is assembled on a glassy carbon electrode with N-MHG/Nafion membrane and characterized by cyclic voltammetry and electrochemical impedance spectroscopy.

The impact of healthy parenting as a protective factor for posttraumatic stress disorder in adulthood: a case-control study.

BACKGROUND: Early life social adversity can influence stress response mechanisms and is associated with anxious behaviour and reductions in callosal area later in life. OBJECTIVE: To evaluate the association between perceptions of parental bonding in childhood/adolescence, hypothalamic-pituitary-adrenal (HPA) axis response, and callosal structural integrity in adult victims of severe urban violence with and without PTSD. METHODS: Seventy-one individuals with PTSD and 62 without the disorder were assessed with the Parental Bonding Instrument (PBI). The prednisolone suppression test was administered to assess cortisol levels, and magnetic resonance imaging was used to assess the total area of the corpus callosum (CC), as well as the areas of callosal subregions. RESULTS: The PBI items related to the perception of 'not having a controlling mother' (OR 4.84; 95%CI [2.26-10.3]; p=0.01), 'having a caring father' (OR 2.46; 95'%CI [1.18-5.12]; p=0.02), and 'not having controlling parents' (OR 2.70; 95%CI [1.10-6.63]; p=0.04) were associated with a lower risk of PTSD. The PTSD group showed a blunted response to the prednisolone suppression test, with lower salivary cortisol levels upon waking up (p=0.03). Individuals with PTSD had smaller total CC area than those without the disorder, but these differences were not statistically significant (e-value =0.34). CONCLUSIONS: Healthy parental bonding, characterized by the perception of low parental control and high affection, were associated with a lower risk of PTSD in adulthood, suggesting that emotional enrichment and the encouragement of autonomy are protective against PTSD in adulthood.