Influence of odor environments on cognitive efficiency: A comprehensive review.

Cognitive efficiency, characterized by the rapid and accurate processing of information, significantly enhances work and learning outcomes. This efficiency manifests in improved time management, decision-making, learning capabilities, and creativity. While the influence of thermal, acoustic, and lighting conditions on cognitive performance has been extensively studied, the role of olfactory stimuli remains underexplored. Olfactory perception, distinguished by its intensity, speed of perception, and the breadth of stimuli, plays a pivotal role in cognitive efficiency. This review investigates the mechanisms through which odor environments influence cognitive performance. We analyze how odor environments can affect cognitive efficiency through two different scenarios (work and sleep) and pathways (direct and indirect effects). Current research, which mainly focuses on the interplay between odors, emotional responses, and cognitive efficiency through both subjective and objective measures, is thoroughly analyzed. We highlight existing research gaps and suggest future directions for investigating the influence of odor environments on cognitive efficiency. This review aims to establish a theoretical basis for managing and leveraging odor environments in workplace settings.

Four-quadrant retarder array imaging spectropolarimeter for the full Stokes vector spectrum.

Aiming at the major demand for polarization information gap in earth observation and space exploration, we proposed a four-quadrant retarder array imaging spectropolarimeter (FQRAISP) in view of the existing technical problem of the spectral resolution degradation along with spectral aliasing crosstalk. The optical schematic diagram of the FQRAISP together with its interference model was conceptually described, and the effectiveness of the scheme was validated through the experimental simulation, which demonstrated the competitive efficiency and accuracy in the proposed FQRAISP. The FQRAISP could restore the incident Stokes vector spectrum without any errors, and the inversion accuracy was increased by seven times, avoiding the spectrum aliasing and channel filtering in the channel modulation. In order to evaluate the influences of the alignment deviation of four-partition phase retarder component, together with its thickness deviation on the reconstructed Stokes parameters, the numerical simulations were carried out, and the results showed that the alignment deviations had a relatively weak effect on the reconstructed Stokes spectra, while the thickness deviations had an obvious influence. Therefore, the alignment deviations controlled in a range of [-0.43∘,+0.43∘] and [-0.22∘, + 0.22∘] together with the thickness deviations in a range of [ - 0.03µm, + 0.03µm] were an optimal choice for the engineering implementation of the FQRAISP. This research provided a novel method for the hardware realization of the accurate acquisition of all-optical information, having broad application prospects in remote sensing (deep space exploration), biomedicine and other fields.

Securinine Promotes Neuronal Development and Exhibits Antidepressant-like Effects via mTOR Activation.

Impaired differentiation of newborn neurons or abnormalities at the synapses resulted from stress maladaptation could be the key etiology of depression. Recent studies have shown that mTOR, a crucial factor for neuronal differentiation and synapse development, acts as a common factor that mediates the rapid antidepression effects of several new-class antidepressants. In this study, the antidepressant-like activity of securinine, an alkaloid that has central nervous system stimulation ability, was investigated. Both securinine and its enantiomer virosecurinine exhibited potent in vitro activity on neuronal differentiation and synapse development in Neuro-2a cells and cultured hippocampal neurons, and this activity was dependent on the activation of the AKT-mTOR-S6K pathway. Interestingly, only securinine but not virosecurinine showed mTOR stimulation and antidepressant-like activity in mice. Importantly, a single dose of securinine was capable of alleviating the behavioral deficits induced by both acute and chronic stress models within 30 min of administration, suggesting that securinine has rapid onset of action. Moreover, neither a single dose nor a 3 week treatment of securinine had adverse effects on exploratory locomotion of mice. Together, this study identifies that securinine is a potent agent in promoting neuronal differentiation and synapse formation and shows rapid antidepressant-like activity, without inducing abnormal locomotion, via mTOR activation.

7-(4-Hydroxy-3-methoxyphenyl)-1-phenyl-4E-hepten-3-one alleviates Aß1-42 induced cytotoxicity through PI3K-mTOR pathways.

Alzheimer's disease (AD) is the most common neurodegenerative disease in the elderly. Increasing evidence has shown that ß-amyloid protein (Aß) production is the key pathological cause of AD. 7-(4-Hydroxy-3-methoxyphenyl)-1-phenyl-4E-hepten-3-one (AO-2), a natural diarylheptanoid, is previously found to have activities in neuronal differentiation and neurite outgrowth, and its analogue shows protective effects against Aß. In this study, we further investigated the function of AO-2 toward Aß-induced injuries in PC12 cells and hippocampal neurons. Pretreatment of PC12 cells with AO-2 restored cell viability in a concentration-dependent manner against Aß-induced neurotoxicity. Moreover, the Aß stimulated apoptosis and caspase-3 activation were markedly inhibited by AO-2. We found that AO-2 prevented the downregulation of PI3K-Akt-mTOR signaling after Aß damage, and blockade of either PI3K or mTOR activity led to the failure of AO-2 on caspase-3 inhibition. We further showed that AO-2 was protective against two devastating effects of Aß, increased reactive oxygen species (ROS) production and dendrite injury, and this protection was also dependent on PI3K and mTOR activities. Taken together, this study showed that AO-2 acts against Aß-induced damages in PC12 cells and hippocampal neurons through PI3K-mTOR pathways, thus providing a new neuroprotective compound which may shed light on drug development of AD.