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Introduction: Pregnant women may need to undergo non‐obstetric surgery under general anesthesia owing to medical needs, and pregnant women frequently experience sleep disturbances during late gestation. Preclinical studies demonstrated that maternal isoflurane exposure (MISO) or maternal sleep deprivation (MSD) contributed to cognitive impairments in offspring. Research studies in mice have revealed that SD can aggravate isoflurane‐induced cognitive deficits. However, it remains unclear whether MSD aggravates MISO‐induced cognitive deficits in offspring. The purpose of this research was to explore the combined effects of MSD and MISO on offspring cognitive function and the role of neuroinflammation and synaptic function in the process of MSD + MISO. Methods: Pregnant mice were exposed to 1.4% isoflurane by inhalation for 4 h on gestational day (GD) 14. Dams were then subjected to SD for 6 h (12:00–18:00 h) during GD15–21. At 3 months of age, the offspring mice were subjected to the Morris water maze test to assess cognitive function. Then the levels of inflammatory and anti‐inflammatory markers and synaptic function‐related proteins were assessed using molecular biology methods. Results: The results of this study demonstrated that MISO led to cognitive dysfunction, an effect that was aggravated by MSD. In addition, MSD exacerbated the maternal isoflurane inhalation, leading to an enhancement in the expression levels of interleukin (IL)‐1β, IL‐6, and tumor necrosis factor‐alpha and a reduction in the hippocampal levels of IL‐10, synaptophysin, post‐synaptic density‐95, growth‐associated protein‐43, and brain‐derived neurotrophic factor. Conclusion: Our findings revealed that MSD aggravated the cognitive deficits induced by MISO in male offspring mice, and these results were associated with neuroinflammation and alternations in synaptic function. [ABSTRACT FROM AUTHOR]

One two‐dimensional (2D) GdIII coordination polymer based on isonicotinic acid N‐oxide (HINNO), {[Gd(INNO)2(HCOO)] ⋅ 2H2O}n (1), was successfully synthesized and characterized. Magnetic studies reveal the presence of weak antiferromagnetic couplings between adjacent GdIII ions in the 1D chain units of 1 and large cryogenic magnetocaloric effect with maximum −ΔSm of 31.84 J kg−1 K−1 at T=2 K and ΔH=7 T. [ABSTRACT FROM AUTHOR]

A thermodynamic model is established to investigate the effects of internal stress in PbZrO3 (PZ) antiferroelectric (AFE) film on the barocaloric effect (BCE), electrocaloric effect (ECE), and energy storage properties. It is found that the internal stress can change the phase transition behaviors and free energy barriers among AFE, ferroelectric (FE), and paraelectric (PE) phases. For the BCE, it occurs only in the FE phase induced by stress or temperature. Under a certain temperature, the optimized negative and positive ECE can be obtained by controlling the internal stress and electric field. In addition, the switching electric field of the AFE→FE phase transition increases and causes a larger recoverable energy density with decreasing tensile stress. These results are analyzed and explained by tricritical points (3 cp) with different stresses, temperatures, and electric fields. Therefore, this thermodynamic model provides an effective route to optimize the BCE, ECE, and energy storage properties of PZ films. [ABSTRACT FROM AUTHOR]

Pb0.99Nb0.02(Zr0.85Sn0.13Ti0.02)O3 (PNZST) antiferroelectric (AFE) thick films are successfully deposited on silicon‐based Pt and LaNiO3 electrodes by a sol‐gel method. The coexistence of ferroelectric (FE) and AFE phases are revealed in PNZST films by XRD, electric‐induced hysteresis loops, dielectric, and leakage current properties. Comparing with PNZST/Pt film, larger recoverable energy density and efficiency are obtained in PNZST/LaNiO3 film due to the lower FE phase proportion. It is analyzed and demonstrated by a thermodynamic model of AFE and FE coexistence system. In addition, the fatigue behaviors of both AFE films are also affected by the proportion of the coexisting FE phase. PNZST/LaNiO3 film exhibits good fatigue resistance on energy storage even after 1010 switching cycles, which is attractive to pulsed power applications. [ABSTRACT FROM AUTHOR]

The polycyclic p-quinodimethanes are proposed to be the novel candidates of the high-performance nonlinear optical (NLO) materials because of their large third order polarizabilities ( γ). We investigate the switchable NLO responses of a series of polycyclic p-quinodimethanes with redox properties by employing the density functional theory (DFT). The polycyclic p-quinodimethanes are forecasted to exhibit obvious pure diradical characters because of their large y0 index (the y0 index is a value between 0 [closed-shell state] and 1 [pure biradical state]). The γ values of these polycyclic p-quinodimethanes and their corresponding one-electron and two-electron reduced/oxidized species are calculated by the (U)BHandHLYP method. The γ values of polycyclic p-quinodimethanes and their corresponding one-electron reduced species are all positive and significantly different. The large differences of the γ values are due to a change in the transition energy and are related to the different delocalization of the spin density, which demonstrates that the NLO switching is more effective on one-electron reduction reactions. Therefore, the study on these polycyclic p-quinodimethanes provides a guideline for a molecular design of highly efficient NLO switching. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Intermittent hypoxia (IH), a major pathophysiologic alteration in obstructive sleep apnea syndrome (OSAS), is an important contributor to cognitive impairment. Increasing research suggests that melatonin has anti-inflammatory properties and improves functions related to synaptic plasticity. However, it is unclear whether melatonin has a protective effect against OSAS-induced cognitive dysfunction in aged individuals and the involved mechanisms are also unclear. Therefore, in the study, the effects of exposure to IH alone and IH in combination with daily melatonin treatment were investigated in C57BL/6 J mice aged 18 months. Assessment of the cognitive ability of mice in a Morris water maze showed that melatonin attenuated IH-induced impairment of learning and memory in aged mice. Enzyme-linked immunosorbent assay, polymerase chain reaction, and western blotting molecular techniques showed that melatonin treatment reduced the levels of the proinflammatory cytokines, interleukin-1β, interleukin-6, and tumor necrosis factor-α, decreased the levels of NOD-like receptor thermal protein domain associated protein 3 and nuclear factor kappa-B, lowered the levels of ionized calcium-binding adapter molecule 1 and glial fibrillary acidic protein, and increased the levels of the synaptic proteins, activity-regulated cytoskeleton-associated protein, growth-associated protein-43, postsynaptic density protein 95, and synaptophysin in IH-exposed mice. Moreover, electrophysiological results showed that melatonin ameliorated the decline in long-term potentiation induced by IH. The results suggest that melatonin can ameliorate IH-induced cognitive deficits by inhibiting neuroinflammation and improving synaptic plasticity in aged mice., Competing Interests: Declaration of Competing Interest All authors declare no competing financial interests or potential conflicts of interest., (Copyright © 2024. Published by Elsevier Ltd.)