RESUMO
Prenatal substance exposure (PSE) has been linked to adverse health outcomes, but its interactions with environmental and genetic factors remain unclear. Using data from the adolescent brain cognitive development cohort (n = 9,838; baseline age: 9.92 ± 0.62 years), we tested for the robust associations of PSE-caffeine/alcohol/tobacco/marijuana with children's health, cognition, and brain metrics after controlling for the environmental and genetic contexts. The environmental context involved birth, familial, and societal risk factors, while the genetic context included family histories and polygenic risk scores (PRSs) of mental disorders. In this sample, PSE-caffeine was observed in 59.8%, PSE-alcohol in 25.7%, PSE-tobacco in 13.2%, and PSE-marijuana in 5.6% of children. PSE-tobacco/marijuana was associated with higher environmental risks, PSE-alcohol was associated with lower familial risks, and all PSEs were associated with higher genetic risks. Controlling for these contexts reduced the number of significant health associations by 100, 91, 84, and 18% for PSE-tobacco/marijuana/caffeine/alcohol. Compared to the baseline, PSE-alcohol had the most health associations that were persistent over a 2-year period from preadolescence to adolescence, including associations with more sleep and mental health problems, improved cognitive functions, and larger brain volumes. These persistent associations with mental health problems and crystallized cognition were mediated by the surface areas of the frontal and the parietal cortices, respectively. Lower risk scores of the familial contexts attenuated associations between PSE-alcohol/marijuana and mental health problems. Higher PRS for substance use disorders enhanced late-onset associations of PSE-marijuana with externalizing problems. Results support the "health in context" concept, emphasizing modifiable factors mitigating adverse PSE effects.
RESUMO
Humidity- and moisture-induced degradation has been a longstanding problem in perovskite materials, affecting their long-term stability during applications. Counterintuitively, the moisture is leveraged to tailor the reversible hydrochromic behaviors of a new series of 2D Dion-Jacobson (DJ) perovskites for reconfigurable optoelectronics. In particular, the hydrogen bonds between organic cations and water molecules can be dynamically modulated via moisture removal/exposure. Remarkably, such modulation confines the movement of the organic cations close to the original position, preventing their escape from crystal lattices. Furthermore, this mechanism is elucidated by theoretical analysis using first-principles calculations and confirmed with the experimental characterizations. The reversible fluorescent transition 2D DJ perovskites show excellent cyclical properties, presenting untapped opportunities for reconfigurable optoelectronic applications. As a proof-of-concept demonstration, an anti-counterfeiting display is shown based on patterned reversible 2D DJ perovskites. The results represent a new avenue of reconfigurable optoelectronic application with 2D DJ perovskites for humidity detection, anti-counterfeiting, sensing, and other emerging photoelectric intelligent technologies.
RESUMO
Recently, the polarization effect has been receiving tremendous attention, as it can result in improved stability and charge transfer efficiency of metal-halide perovskites (MHPs). However, realizing the polarization effect on CsPbX3 NCs still remains a challenge. Here, metal ions with small radii (such as Mg2+, Li+, Ni2+, etc.) are introduced on the surface of CsPbX3 NCs, which facilitate the arising of electric dipole and surface polarization. The surface polarization effect promotes redistribution of the surface electron density, leading to reinforced surface ligand bonding, reduced surface defects, near unity photoluminescence quantum yields (PLQYs), and enhanced stability. Moreover, further introduction of hydroiodic acid results in the in situ formation of tert-butyl iodide (TBI), which facilitates the successful synthesis of pure iodine-based CsPbI3 NCs with high PLQY (95.3%) and stability under ambient conditions. The results of this work provide sufficient evidence to exhibit the crucial role of the surface polarization effect, which promotes the synthesis of high-quality MHPs and their applications in the fields of optoelectronic devices.
RESUMO
A water-soluble glucan, BCG-PASW, with a molecular weight of 2.10×10(4)Da, was separated from polysaccharide nucleic acid fraction of Bacillus Calmette Guerin (BCG-PSN) using DEAE-52 cellulose and Sephadex G-200 chromatography. Based on gas chromatography-mass spectrometry (GC-MS), fourier transform infrared (FT-IR) spectra, 1D and 2D nuclear magnetic resonance (NMR) spectroscopy techniques (COSY, HSQC and HMBC), BCG-PASW was found to be an α-d-glucan composed of α-d-(1â4)-linked glucopyranosyl residues, with branches at O-6 consisting of non-reducing terminal α-d-Glcp approximately every eight residues. In vitro antitumor activity by MTS method, its sulfated derivative with a substitution degree of 0.59, could inhibite C666-1 nasopharyngeal carcinoma cells growth significantly. The results indicated that the sulfate content play a decisive role in the bioactivities of the polysaccharides.