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As we listen to speech, our ability to understand what was said requires us to retrieve and bind together individual word meanings into a coherent discourse representation. This so-called semantic unification is a fundamental cognitive skill, and its development relies on the integration of neural activity throughout widely distributed functional brain networks. In this proof-of-concept study, we examine, for the first time, how these functional brain networks develop in children. Twenty-six children (ages 4-17) listened to well-formed sentences and sentences containing a semantic violation, while EEG was recorded. Children with stronger vocabulary showed N400 effects that were more concentrated to centroparietal electrodes and greater EEG phase synchrony (phase lag index; PLI) between right centroparietal and bilateral frontocentral electrodes in the delta frequency band (1-3 Hz) 1.27-1.53 s after listening to well-formed sentences compared to sentences containing a semantic violation. These effects related specifically to individual differences in receptive vocabulary, perhaps pointing to greater recruitment of functional brain networks important for top-down semantic unification with development. Less skilled children showed greater delta phase synchrony for violation sentences 3.41-3.64 s after critical word onset. This later effect was partly driven by individual differences in nonverbal reasoning, perhaps pointing to non-verbal compensatory processing to extract meaning from speech in children with less developed vocabulary. We suggest that functional brain network communication, as measured by momentary changes in the phase synchrony of EEG oscillations, develops throughout the school years to support language comprehension in different ways depending on children's verbal and nonverbal skill levels.

In this study, MXene quantum dots-functionalized polyethylenimine was composited with melamine-based covalent organic framework (MXene QDs-PEI/COF) and utilized for sensitive and selective determination of Hg2+ in water samples using differential pulse anodic stripping voltammetry (DPASV). The prepared pencil graphite electrode-modified MXene QDs-PEI/COF was carefully characterized with field emission scanning electron microscopy, Fourier transform infrared, X-ray diffraction, fluorescence spectroscopy, electrochemical impedance spectroscopy, and cyclic voltammetry in detail. Electroactive surface area of the PGE/MXene QDs-PEI/COF was calculated to be 0.23 cm2 which was remarkably improved in comparison with PGE/COF and PGE/MXene QDs-PEI with the surface areas of 0.0067 and 0.189 cm2. The obtained results with DPASV technique for Hg2+ determination resulted a linear analytical response (R2 = 0.9944) in the concentration range of 50 nM to 35 µM, with the sensitivity of 16.973 µA µM−1 cm−2 and detection limit of 16 nM (S/N = 3). The developed method was utilized carefully for mercury analysis in Caspian Seawater and tap water samples with suitable precision and accuracy. [ABSTRACT FROM AUTHOR]

Background. Psoriasis is a noncontagious auto‐inflammatory chronic skin disease. So far, some of the inflammatory genes were upregulated in mouse model of psoriasis. This study examined changes in skin mRNA expression of L‐kynureninase (Kynu), cathelicidin antimicrobial peptide (Camp), beta‐defensin 2 (Defb2), and proenkephalin (Penk) in a mouse model of imiquimod‐induced psoriasis. Materials and Methods. Tree groups of C57BL/6 female mice were allocated. The imiquimod (IMQ) cream was administered to the mice dorsal skin of the two groups to induce psoriatic inflammation. In the treatment group, IMQ was administered 10 min after hydrogel‐containing M7 anti‐IL‐17A aptamer treatment. Vaseline (Vas) was administered to the negative control group. The psoriatic skin lesions were evaluated based on the psoriasis area severity index (PASI) score, histopathology, and mRNA expression levels of Kynu, Camp, Defb2, and Penk using real‐time PCR. In order to assess the systemic response, the spleen and lymph node indexes were also evaluated. Results. The PASI and epidermal thickness scores were 6.01 and 1.96, respectively, in the IMQ group, and they significantly decreased after aptamer administration to 1.15 and 0.90, respectively (P < 0.05). Spleen and lymph node indexes showed an increase in the IMQ group, followed by a slight decrease after aptamer treatment (P > 0.05). Additionally, the mRNA expression levels of Kynu, Defb2, Camp, and Penk genes in the IMQ‐treated region showed a significant 2.70, 4.56, 3.29, and 2.61‐fold increase relative to the Vas mice, respectively (P < 0.05). The aptamer‐treated region exhibited a significant decrease in these gene expression levels (P < 0.05). A positive correlation was found between Kynu, Penk, and Camp expression levels and erythema, as well as Camp expression with PASI, scaling, and thickness (P < 0.05). Conclusion. According to our results, it seems that Kynu, Camp, and Penk can be considered appropriate markers for the evaluation of psoriasis in IMQ‐induced psoriasis. Also, the anti‐IL‐17 aptamer downregulated these important genes in this mouse model. [ABSTRACT FROM AUTHOR]

Phase Change Materials (PCMs) have received much consideration as thermal energy storage systems due to their high storage capacity. However, their heat transfer rate is limited because of the low thermal conductivity. Incorporating of carbon-based nanoparticles into the matrix of PCMs with good dispersion can be an efficient way to solve their deficiency. In this research, graphite nanoparticles were homogeneously dispersed within the Eicosane PCM matrix to prepare a Nano-Enhanced PCM (NEPCM). The main objective is to determine the optimum amount of graphite to maximize the thermal properties of NEPCM composites. The Scanning Electron Microscopy (SEM) images of the prepared nanocomposites confirmed the excellent dispersion of graphite nanoparticles within the Eicosane layers through an ultrasonic bath-assisted homogenization procedure followed by solidification. In addition, Differential Scanning Calorimetry (DSC) and Thermal Conductivity Evaluation (TC) of the samples were conducted to determine their heat capacity and thermal diffusivity. The results illustrated that the more the number of graphite nanoparticles, the larger the number of collisions between graphite and Eicosane. As the nanoparticle content increased, the thermal conductivity and diffusivity were enhanced, as well. Numerically, the maximum thermal conductivity was 4.1 W/m K for the composite containing 10 wt% graphite, 15.66 times that of the pure Eicosane. Furthermore, increasing crystal growth and reducing heat capacity for the large number of nanoparticles in the composite were discussed. The significantly improved thermal properties of the prepared NEPCMs with an optimal nanoparticle content could make them applicable for different thermal management applications. [ABSTRACT FROM AUTHOR]