Separately enhanced dual emissions of the amphiphilic derivative of 2-(2'-hydroxylphenyl) benzothiazole by supramolecular complexation.

Here, we report separately enhanced dual emissions of the amphiphilic derivative of 2-(2'-hydroxyphenyl)benzothiazole (denoted as HBT-11) by supramolecular complexation with cyclodextrins (CDs). When dispersed in water, HBT-11 shows two relatively weak emission bands, which can be assigned to the emissions of enol- and keto-forms, the two tautomers, owing to excited-state intramolecular proton transfers. Upon the addition of α-CD and ß-CD, the keto- and enol-emissions, respectively, are separately enhanced; the enhancement effect is due to the formation of HBT-11/α-CD and HBT-11/ß-CD complexes through multiple hydrogen bonding and host-guest interactions, respectively. It is worth to note that the keto-emission caused by the complex of HBT-11/α-CD has a much shorter wavelength compared with that of the aggregates formed by pure HBT-11. To the best of our knowledge, this is the first time that a study on keto-emission of the isolated HBT chromophore has been reported.

Tuning the emission of a water-soluble 3-hydroxyflavone derivative by host-guest complexation.

3-Hydroxyflavone derivatives have great potential as fluorescent probes for bio-labeling in aqueous medium. They were extensively studied in various organic solvents for the "excited state intramolecular proton transfer" process, but seldom addressed in aqueous solution due to the poor water solubility. Herein, an amphiphilic molecule bearing 3-hydroxyflavone and oligo(ethylene oxide) (denoted as 3HF-EO) was designed and synthesized. Different from the fluorescence in organic solvents, 3HF-EO in aqueous solution showed a remarkable single fluorescence emission, which is ascribed to the fluorescence of its anionic species. We found that the fluorescence intensity could be efficiently tuned via host-guest complexation. α-CD has little effect on the emission, while ß-CD and γ-CD lead to enhanced and reduced emissions of 3HF-EO, respectively. The 1H NMR and 2D NOESY NMR spectra indicate that α-CD barely had any interaction with 3HF-EO, while ß-CD and γ-CD formed complexes with one and two 3HF-EO molecules, respectively. These results provide a sound explanation for the modulated fluorescence intensity.

Chemical Modification of n-Type-Material Naphthalene Diimide on ITO for Efficient and Stable Inverted Polymer Solar Cells.

To provide orthogonal solvent processable surface modification and improve the device stability of bulk-heterojunction polymer solar cells (PSCs), n-type semiconducting material naphthalene diimide (NDI) was chemically introduced onto the ITO surface as a cathode interlayer (CIL) using 3-bromopropyltrimethoxysilane (BrTMS) as a coupling agent. After modification, the work function of ITO can be decreased from 4.70 to 4.23 eV. The modified ITO cathode was applied in inverted PSCs based on PTB7-Th:PC71BM. With the CIL modification, a champion power conversion efficiency (PCE) of 5.87% was achieved, showing a dramatic improvement compared to that of devices (PCE = 3.58%) without CIL. More importantly, with these chemical bonded interlayers, the stability of inverted PSCs was greatly enhanced. The improved PCE and stability can be attributed to the increased open-circuit voltage and the formation of robust chemical bonds in NDI-TMS films, respectively. This study demonstrated that chemical modification of ITO with n-type semiconducting materials provides an avenue for not only solving the solvent orthogonal problem but also improving the device performance in terms of the PCE and the stability.

Stably Grafting Polymer Brushes on Both Active and Inert Surfaces Using Tadpole-Like Single-Chain Particles with an Interactive "Head".

We report a "grafting to" method for stably grafting high-molecular-weight polymer brushes on both active and inert surfaces using tadpole-like single-chain particles (TSCPs) with an interactive "head" as grafting units. The TSCPs can be efficiently synthesized through intrachain cross-linking one block of a diblock copolymer; the "head" is the intrachain cross-linked single-chain particle, and the "tail" is a linear polymer chain that has a contour length up to micrometers. When grafted to a surface, the "head", integrating numerous interacting groups, can synergize multiple weak interactions with the surface, thereby enabling stable grafting of the "tail" on both active and traditionally challenging inert surfaces. Because the structural parameters and composition of the "heads" and "tails" can be separately adjusted over a wide range, the interactivity of the "heads" with the surface and properties of the brushes can be controlled orthogonally, accomplishing surface brushes that cannot be achieved by existing methods.

Emotion Recognition of Subjects With Hearing Impairment Based on Fusion of Facial Expression and EEG Topographic Map.

Emotion analysis has been employed in many fields such as human-computer interaction, rehabilitation, and neuroscience. But most emotion analysis methods mainly focus on healthy controls or depression patients. This paper aims to classify the emotional expressions in individuals with hearing impairment based on EEG signals and facial expressions. Two kinds of signals were collected simultaneously when the subjects watched affective video clips, and we labeled the video clips with discrete emotional states (fear, happiness, calmness, and sadness). We extracted the differential entropy (DE) features based on EEG signals and converted DE features into EEG topographic maps (ETM). Next, the ETM and facial expressions were fused by the multichannel fusion method. Finally, a deep learning classifier CBAM_ResNet34 combined Residual Network (ResNet) and Convolutional Block Attention Module (CBAM) was used for subject-dependent emotion classification. The results show that the average classification accuracy of four emotions recognition after multimodal fusion achieves 78.32%, which is higher than 67.90% for facial expressions and 69.43% for EEG signals. Moreover, visualization by the Gradient-weighted Class Activation Mapping (Grad-CAM) of ETM showed that the prefrontal, temporal and occipital lobes were the brain regions closely related to emotional changes in individuals with hearing impairment.

A Novel Domain Adversarial Networks Based on 3D-LSTM and Local Domain Discriminator for Hearing-Impaired Emotion Recognition.

Recent research on emotion recognition suggests that deep network-based adversarial learning has an ability to solve the cross-subject problem of emotion recognition. This study constructed a hearing-impaired electroencephalography (EEG) emotion dataset containing three emotions (positive, neutral, and negative) in 15 subjects. The emotional domain adversarial neural network (EDANN) was carried out to identify hearing-impaired subjects' emotions by learning hidden emotion information between the labeled data and the data with no-label. For the input data, we propose a spatial filter matrix to reduce the overfitting of the training data. A feature extraction network 3DLSTM-ConvNET was used to extract comprehensive emotional information from the time, frequency, and spatial dimensions. Moreover, emotion local domain discriminator and emotion film group local domain discriminator were added to reduce the distribution distance between the same kinds of emotions and different film groups, respectively. According to the experimental results, the average accuracy of subject-dependent is 0.984 (STD: 0.011), and that of subject-independent is 0.679 (STD: 0.140). In addition, by analyzing the discrimination characteristics, we found that the brain regions with emotional recognition in the hearing-impaired are distributed in the wider areas of the parietal and occipital lobes, which may be caused by visual processing.

Boosting Organic Afterglow Performance via a Two-Component Design Strategy Extracted from Macromolecular Self-Assembly.

Because intersystem crossing and phosphorescence decay are spin-forbidden in organic systems, it is challenging to obtain high-performance organic afterglow materials. Inspired by two-component design strategy from macromolecular self-assembly, here we report the utilization of synthetic polymers to control the excited state properties of difluoroboron ß-diketonate (BF2bdk) and deuterated BF2bdk compounds for the fabrication of room-temperature organic afterglow materials. The polymer component can interact with BF2bdk excited states by dipole-dipole interactions, lower BF2bdk S1 levels with insignificant effect on T1 levels, reduce ΔEST, and thus enhance intersystem crossing of BF2bdk excited states. The polymer component can also suppress intramolecular motion of BF2bdk triplets and protect BF2bdk triplets from oxygen quenching. The obtained BF2bdk-polymer afterglow materials exhibit emission lifetimes up to 2.2 s and high photoluminescence quantum yields under ambient conditions, display excellent processability and flexibility, and can function as efficient donors for excited state energy transfer to construct red afterglow materials.

African Swine Fever Virus K205R Induces ER Stress and Consequently Activates Autophagy and the NF-κB Signaling Pathway.

African swine fever virus (ASFV) is responsible for enormous economic losses in the global swine industry. The ASFV genome encodes approximate 160 proteins, most of whose functions remain largely unknown. In this study, we examined the roles of ASFV K205R in endoplasmic reticulum (ER) stress, autophagy, and inflammation. We observed that K205R was located in both the cytosolic and membrane fractions, and formed stress granules in cells. Furthermore, K205R triggered ER stress and activated the unfolded protein response through activating the transcription factor 6, ER to nucleus signaling 1, and eukaryotic translation initiation factor 2 alpha kinase 3 (EIF2AK3/PERK) signaling pathways. Moreover, K205R inhibited the serine/threonine kinase 1 and the mechanistic target of the rapamycin kinase signaling pathway, thereby activating unc-51 like autophagy activating kinase 1, and hence autophagy. In addition, K205R stimulated the translocation of P65 into the nucleus and the subsequent activation of the nuclear factor kappa B (NF-κB) signaling pathway. Inhibition of ER stress with a PERK inhibitor attenuated K205R-induced autophagy and NF-κB activation. Our data demonstrated a previously uncharacterized role of ASFV K205R in ER stress, autophagy, and the NF-κB signaling pathway.

NPC1-regulated dynamic of clathrin-coated pits is essential for viral entry.

Viruses utilize cellular lipids and manipulate host lipid metabolism to ensure their replication and spread. Therefore, the identification of lipids and metabolic pathways that are suitable targets for antiviral development is crucial. Using a library of compounds targeting host lipid metabolic factors and testing them for their ability to block pseudorabies virus (PRV) and vesicular stomatitis virus (VSV) infection, we found that U18666A, a specific inhibitor of Niemann-Pick C1 (NPC1), is highly potent in suppressing the entry of diverse viruses including pseudotyped severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). NPC1 deficiency markedly attenuates viral growth by decreasing cholesterol abundance in the plasma membrane, thereby inhibiting the dynamics of clathrin-coated pits (CCPs), which are indispensable for clathrin-mediated endocytosis. Significantly, exogenous cholesterol can complement the dynamics of CCPs, leading to efficient viral entry and infectivity. Administration of U18666A improves the survival and pathology of PRV- and influenza A virus-infected mice. Thus, our studies demonstrate a unique mechanism by which NPC1 inhibition achieves broad antiviral activity, indicating a potential new therapeutic strategy against SARS-CoV-2, as well as other emerging viruses.

Heterogeneous Transport of Free CH4 and Free CO2 in Dual-Porosity Media Controlled by Anisotropic In Situ Stress during Shale Gas Production by CO2 Flooding: Implications for CO2 Geological Storage and Utilization.

Regarding shale gas production by CO2 flooding, few existing reports explain the performance of free CH4 and free CO2 in shale reservoirs controlled by anisotropic in situ stress, partly restricting the integrated recognition of shale-based CO2 geological storage and utilization (CGSU). In this work, a self-developed model embedded with thermo-hydro-mechanical coupling relationships is introduced to investigate how the anisotropic in situ stress determines the transport of free gases (CH4 and CO2) after CO2 is injected into the shale. Therefore, the stronger anisotropy of in situ stress enables more CO2 in the free phase to be trapped in the shale reservoir and is insignificant for the content of residual free CH4 compared to the situation under isotropic in situ stress. Along with CO2 injection into the shale, the matrix porosity decreases invariably, while the fracture porosity decreases first and then increases gradually. Therein, the variation amplitude of the matrix/fracture porosity is more distinct under a stronger anisotropic in situ stress. The simulations also suggest that the ratio of free CO2 relative to all free gases in shale is ∼65% at most after sufficient CGSU operation. Hopefully, this comprehensive work is helpful in enhancing the knowledge on the promising shale-based low-carbon CGSU technique.

Facial expression recognition based on Electroencephalogram and facial landmark localization.

BACKGROUND: Facial expression recognition plays an essential role in affective computing, mental illness diagnosis and rehabilitation. Therefore, facial expression recognition has attracted more and more attention over the years. OBJECTIVE: The goal of this paper was to improve the accuracy of the Electroencephalogram (EEG)-based facial expression recognition. METHODS: In this paper, we proposed a fusion facial expression recognition method based on EEG and facial landmark localization. The EEG signal processing and facial landmark localization are the two key parts. The raw EEG signals is preprocessed by discrete wavelet transform (DWT). The energy feature vector is composed of energy features of the reconstructed signal. For facial landmark localization, images of the subjects' facial expression are processed by facial landmark localization, and the facial features are calculated by landmarks of essence. In this research, we fused the energy feature vector and facial feature vector, and classified the fusion feature vector with the support vector machine (SVM). RESULTS: From the experiments, we found that the accuracy of facial expression recognition was increased 4.16% by fusion method (86.94 ± 4.35%) than EEG-based facial expression recognition (82.78 ± 5.78%). CONCLUSION: The proposed method obtain a higher accuracy and a stronger generalization capability.

A Microfluidic Detection System for Bladder Cancer Tumor Cells.

The clinical characteristics of excreted tumor cells can be found in the urine of bladder cancer patients, meaning the identification of tumor cells in urine can assist in bladder cancer diagnosis. The presence of white blood cells and epithelial cells in the urine interferes with the recognition of tumor cells. In this paper, a technique for detecting cancer cells in urine based on microfluidics provides a novel approach to bladder cancer diagnosis. The bladder cancer cell line (T24) and MeT-5A were used as positive bladder tumor cells and non-tumor cells, respectively. The practicality of the tumor cell detection system based on microfluidic cell chip detection technology is discussed. The tumor cell (T24) concentration was around 1 × 104 to 300 × 104 cells/mL. When phosphate buffer saline (PBS) was the diluted solution, the tumor cell detected rate was 63-71% and the detection of tumor cell number stability (coefficient of variation, CV%) was 6.7-4.1%, while when urine was the diluted solution, the tumor cell detected rate was 64-72% and the detection of tumor cell number stability (CV%) was 6.3-3.9%. In addition, both PBS and urine are tumor cell dilution fluid solutions. The sample was analyzed at a speed of 750 microns per hour. Based on the above experiments, a system for detecting bladder cancer cells in urine by microfluidic analysis chip technology was reported. The rate of recognizing bladder cancer cells reached 68.4%, and the speed reached 2 mL/h.

Comprehensive Study of Sol-Gel versus Hydrolysis-Condensation Methods To Prepare ZnO Films: Electron Transport Layers in Perovskite Solar Cells.

Owing to the high charge mobility and low processing temperature, ZnO is regarded as an ideal candidate for electron transport layer (ETL) material in thin-film solar cells. For the film preparation, the presently dominated sol-gel (SG) and hydrolysis-condensation (HC) methods show great potential; however, the effect of these two methods on the performance of the resulting devices has not been investigated in the same frame. In this study, the ZnO films made through SG and HC methods were applied in perovskite solar cells (Pero-SCs), and the performances of corresponding devices were compared under parallel conditions. We found that the surface morphologies and the conductivities of the films prepared by SG and HC methods showed great differences. The HC-ZnO films with higher conductivity led to relatively higher device performance, and the best power conversion efficiencie (PCE) of 12.9% was obtained; meanwhile, for Pero-SCs based on SG-ZnO, the best PCE achieved was 10.9%. The better device performance of Pero-SCs based on HC-ZnO should be attributed to the better charge extraction and transportation ability of HC-ZnO film. Moreover, to further enhance the performance of Pero-SCs, a thin layer of pristine C60 was introduced between HC-ZnO and perovskite layers. By doing so, the quality of perovskite films was improved, and the PCE was elevated to 14.1%. The preparation of HC-ZnO film involves relatively lower-temperature (maximum 100 °C) processing; the films showed better charge extraction and transportation properties and can be a more promising ETL material in Pero-SCs.

[Geochemical distribution and environmental quality of cadmium in river sediment around the Jinding Pb-Zn mine area in Yunnan].

A long-term mining activity of Jinding Pb-Zn mine area in Yunnan has caused the serious cadmium pollution to the river sediments of the ambient area. The Cd contents of Beidagou river sediments (mean value <10 mg x kg(-1)) are lower than those of Nandagou river sediments (mean value = 266 mg x kg(-1)). The Cd contents of river sediments in different section of Bijiang river occur distinct difference. The Cd contents are rather lower in upstream sediments of Bijiang river, and increase substantially along downstream contaminated section of Bijiang river. The Cd pollution coefficient is higher (R = 21.9-45.2) than Zn (R = 4.9-9.7) and Pb (R = 2.7-4.6). The degree of pollution is estimated by the geoaccumulation index, which indicates the following rank of pollution elements: Cd > Zn > Pb. The river sediments are extremely contaminated in Nandagou river and downstream section of Bijiang river from Nandagou, strongly contaminated in most part of Beidagou river, moderately to strongly contaminated in few river section of Nandagou river, uncontaminated or moderately contaminated in upstream of Bijiang river from Jinding. The heavy metals pollution of river sediments presents increasing trend from Nandagou outlet to Wenzhuang section of Bijiang river.