Two-Dimensional Lanthanide Metal-Organic Framework Heterostructures for Noninvasively Photoresponsive High-Security Photonic Barcodes.

Stimuli-responsive micro/nanoscale photonic barcodes show great capacity for encryption and anticounterfeiting technologies due to multiple authentications, yet their application is commonly restricted by invasive stimuli. Herein, we report noninvasive light-stimulated high-security photonic barcodes based on spatially assembled photoresponsive two-dimensional (2D) 1,3,5-benzenetribenzoate (BTB)@Ln-MOF host-guest heterostructures. The photoluminescence (PL) spectra information on BTB@Ln-MOF heterostructures could be precisely controlled by the different wavelengths of ultraviolet (UV) light trigger. By using the PL properties and 2D heterostructures as cryptographic primitives, spatially resolved smart photonic barcodes based on both spectral and graphical coding are realized in BTB@Ln-MOF host-guest materials. These results will pave an avenue for the development of smart stimuli-responsive photonic barcodes for anticounterfeiting applications.

Working Memory Precision and Associative Binding in Mild Cognitive Impairment.

To better understand working memory (WM) deficits in Mild Cognitive Impairment (MCI), we examined information precision and associative binding in WM in 21 participants with MCI, compared to 16 healthy controls, using an item-location delayed reproduction task. WM, along with other executive functions (i.e. Trail Making Task (TMT) and Stroop task), were measured before and after a 2-h nap. The napping manipulation was intended as an exploratory element to this study exploring potential impacts of napping on executive functions.Compared to healthy participants, participants with MCI exhibited inferior performance not only in identifying encoded WM items but also on item-location associative binding and location precision even when only one item was involved. We also found changes on TMT and Stroop tasks in MCI, reflecting inferior attention and inhibitory control. Post-napping performance improved in most of these WM and other executive measures, both in MCI and their healthy peers.Our study shows that associative binding and WM precision can reliably differentiate MCIs from their healthy peers. Additionally, most measures showed no differential effect of group pre- and post-napping. These findings may contribute to better understanding cognitive deficits in MCI therefore improving the diagnosis of MCI.

Telomere-to-telomere genome of the allotetraploid legume Sesbania cannabina reveals transposon-driven subgenome divergence and mechanisms of alkaline stress tolerance.

Alkaline soils pose an increasing problem for agriculture worldwide, but using stress-tolerant plants as green manure can improve marginal land. Here, we show that the legume Sesbania cannabina is very tolerant to alkaline conditions and, when used as a green manure, substantially improves alkaline soil. To understand genome evolution and the mechanisms of stress tolerance in this allotetraploid legume, we generated the first telomere-to-telomere genome assembly of S. cannabina spanning ∼2,087 Mb. The assembly included all centromeric regions, which contain centromeric satellite repeats, and complete chromosome ends with telomeric characteristics. Further genome analysis distinguished A and B subgenomes, which diverged approximately 7.9 million years ago. Comparative genomic analysis revealed that the chromosome homoeologs underwent large-scale inversion events (>10 Mb) and a significant, transposon-driven size expansion of the chromosome 5A homoeolog. We further identified four specific alkali-induced phosphate transporter genes in S. cannabina; these may function in alkali tolerance by relieving the deficiency in available phosphorus in alkaline soil. Our work highlights the significance of S. cannabina as a green tool to improve marginal lands and sheds light on subgenome evolution and adaptation to alkaline soils.

Neurophysiological Correlates of Reading Difficulties in Elementary School Children.

The present study examined the event-related potentials (ERPs) and reading-language skills of elementary school children with and without reading difficulties. Typically developing children showed an N400 effect characterized by significantly larger N400 amplitudes elicited by nonwords than real words. Their meaning processing shown by the N400 systematically differed by lexicality. On the other hand, the N400 effect was absent in children with reading difficultiesExploratory analyses were conducted with the N1 and Late Positive Component. Additionally, the relationships between ERPs and reading-language skills were examined; sight word efficiency and phonemic decoding efficiency accounted for significant variance in the N400 effect.

Defect engineering in two-dimensional perovskite nanowire arrays by europium(III) doping towards high-performance photodetection.

We demonstrate high-performance photodetectors based on Eu-doped 2D perovskite nanowire arrays. The pure crystallographic orientation enables efficient carrier transport and the doped Eu ions effectively suppress the trap density in the nanowire arrays. As a result, the optimized Eu-doped photodetectors show an excellent responsivity of 6.24 A W-1, an outstanding specific detectivity of 5.83 × 1013 Jones and stable photo-switching behavior with a current on/off ratio of 103.

Neural Correlates of Attentional Bias to Food Stimuli in Obese Adolescents.

Adolescent obesity is an increasingly prevalent problem in several societies. Researchers have begun to focus on neurocognitive processes that may help explain how unhealthy food habits form and are maintained. The present study compared attentional bias to food stimuli in a sample of obese (n = 22) and Normal-weight (n = 18) adolescents utilizing an Attention Blink (AB) paradigm while electroencephalography (EEG) was recorded. We found lower accuracy and Event-Related Potential (ERP) P3 amplitudes during the presentation of food stimuli in AB trials for obese adolescents. These findings suggest an impaired ability of their brains to flexibly relocate attentional resources in the face of food stimuli. The results were corroborated by lower P3s also being associated with higher body mass index (BMI) values and poorer self-reported self-efficacy in controlling food intake. The study is among the few examining neural correlates of attentional control in obese adolescents and suggests automatic attentional bias to food is an important aspect to consider in tackling the obesity crisis.

Improved Moisture-Resistant and Luminescence Properties of a Red Phosphor Based on Dodec-fluoride K3RbGe2F12:Mn4+ through Surface Modification.

Mn4+-activated red-emitting fluoride phosphors are essential for white light-emitting diodes (WLEDs) with desirable color rendition index (CRI) because of their unique and efficient luminescence characteristics. Herein, we synthesized a novel Mn4+-activated dodec-fluoride phosphor K3RbGe2F12:Mn4+ (KRGF:Mn) through a facile ionic exchange method at room temperature. A surface-modified strategy using weak reducing agents such as oxalic acid and citric acid is proposed to improve the moisture-resistance ability of KRGF:Mn phosphor dramatically, and the possible mechanism of surface modification has been investigated. A shell formed on the surface of the KRGF:Mn phosphor reduces the concentration of Mn4+ on the surface, which can prevent the internal KRGF:Mn group hydrolysis by the external moisture and effectively decreased the probability of energy migration to surface defects, thereby increasing both the emission efficiency and the moisture-resistance ability of KRGF:Mn. More interestingly, the KRGF:Mn phosphor is quenched after soaking in water for 72 h but recovered to the initial brightness after soaking in the modifier solutions for 2 min. This work fabricates a new efficient red phosphor KRGF:Mn for application in warm WLEDs and provides insight into the mechanism of the strategy to improve the moisture resistance of the stability of Mn4+ through surface modification.

In situ organic solvent-free synthesis of a novel red emitting Mn4+ doped KRbGeF6 phosphor at the room temperature.

Red emitting phosphors of Mn4+ doped fluorides are in high demand because the high color purities of phosphors make them potentially useful white light-emitting diodes (WLEDs) as backlights of electronic devices. We herein report an efficient red emitting phosphor KRbGeF6 : Mn4+ (KRGF : Mn) that was prepared by an in situ one-pot ion-exchange method at room temperature without organic solvents or HF. Homogenous mixtures of the starting materials with a stoichiometric KRGF : Mn ratio were partly dissolved in various acid solutions, and [MnF6]2- and [GeF6]2- successively underwent ion exchange under stirring. More importantly, in situ recrystallization of KRGF : Mn occurred simultaneously in solution with water as a solvent. Evidently, the formation of stable KRGF : Mn crystals propels the processes of dissolution and ion exchange. We also investigated the effect of inorganic acids on the resultant phases and photoluminescence properties of KRGF : Mn. The red phosphor KRGF : Mn prepared in HCl solution shows the highest luminescence intensity with an yield of 80%.

Synthesis and improved photoluminescence of hexagonal crystals of Li2ZrF6:Mn4+ for warm WLED application.

A series of red-emitting phosphors composed of Li2ZrF6:Mn4+ (LZF:Mn) have been synthesized via an ionic-exchange reaction route at room temperature. The microstructure and optical characterizations have been investigated according to the detailed experiments. The morphology of the phosphor LZF:Mn changes with the concentration of HF, the reaction time and temperature. The uniform crystals of LZF:Mn with regular hexagonal tablets have been obtained in 30-40 wt% HF solutions by conducting the reaction at room temperature for about 8 h. The influences of reaction parameters on the morphology and photoluminescence properties of LZF:Mn have been systematically investigated. The luminescence intensity of LZF:Mn has been optimized by controlling the synthesis procedure and parameters. The white light-emitting diode (WLED) fabricated with LZF:Mn and Y3Al5O12:Ce3+ (YAG:Ce) on InGaN LED chip displays a warm white light with correlated color temperature (CCT) at 3789.4 K and color rendering index (CRI) of 91.

Neural differences of inhibitory control between adolescents with obesity and their peers.

BACKGROUND/OBJECTIVE: Inhibitory control, the ability to suppress prepotent responses and resist irrelevant stimuli, is thought to play a critical role in the manifestation and maintenance of obesity in adolescents. Adolescence is a unique developmental stage characterized by significant maturational changes in cortical structures (i.e., prefrontal cortex: PFC) that relate to inhibitory control processes. The current study investigated the behavioral and neurophysiological correlates of inhibitory control in adolescents with obesity. SUBJECTS/METHODS: We compared 18 normal-weight and 22 adolescents with obesity on performance and electroencephalography (EEG)-based measures during a Go/NoGo task. We investigated N2 and P3 event-related potential (ERP) components. RESULTS: Adolescents with obesity showed lower accuracy compared to their normal-weight peers in NoGo trials where greater amounts of inhibitory control effort were required (p = 0.03). Adolescents with obesity had larger NoGo N2 amplitude relative to the Go N2 amplitude (p = 0.03), whereas this difference was not observed in the healthy weight sample. Furthermore, a lower self-efficacy of individual's ability to control eating behaviors in challenging situations (as measured by the Weight Efficacy Lifestyle-Short Form) directly correlated with larger NoGo N2 amplitudes for both obese (p = 0.03) and normal weight groups (p = 0.01). CONCLUSIONS: These findings suggested that obesity in adolescence is associated with a decreased ability to modulate cognitive conflict during the inhibitory control processing. The individual differences in conflict monitoring during situations where greater amounts of inhibitory control effort were required might provide an explanation for overeating behaviors in obese adolescents.