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We propose an unsupervised cross-view facial expression adaptation network(UCFEAN) to simultaneously generate and recognize cross-view facial expressions in images in an unsupervised manner. The main idea of UCFEAN is to convert the unsupervised domain adaptation between two image spaces with different appearance into semi-supervised learning(SSL) in feature spaces with the same semantic content. The cyclic image generation of cross-view facial expressions based on the generative adversarial network(GAN) is carried out to project unlabeled target images and labelled source images to the corresponding feature spaces with the same semantic content. This helps realize the unsupervised feature learning of the target image. Labels of facial expressions represented in the projected target features can then be learned using the projected source features, because the distributions of the projected features in the two domains are close enough for knowledge transfer by using SSL. Three techniques are developed to train UCFEAN in an effective and stable manner. Extensive experiments are conducted to evaluate the UCFEAN on two multi-view facial expression image databases including RaFD and Multi-PIE. The results show that the proposed method can generate realistic target images of the facial expression and recognize cross-view facial expressions with high precision.

A universal amorphous-to-crystalline transformation strategy is developed, and the synthesis and structure regulation of high entropy metal oxide is simultaneously achieved with the structure controlled from solid, to core–shell, to hollow spheres.

Rheumatoid arthritis (RA) is a common autoimmune disease worldwide. Neutrophils play critical roles in the onset and development of RA and are the promising target for RA treatment. Tetrandrine is a bis-benzyl isoquinoline alkaloid derived from the traditional Chinese herbal Stephania tetrandra S. Moore. Tetrandrine is effective in alleviating RA by inhibiting macrophage inflammatory response, fibroblast overproliferation, and pannus formation. However, whether tetrandrine regulates the activities of neutrophils in RA is largely unknown. In this study, we adopted adjuvant-induced arthritis (AA) murine model to explore the effect of tetrandrine on RA and neutrophils. Twenty-eight mice were divided into four groups. The control group was injected with PBS in the limbs and treated with PBS by intraperitoneal injection (i.p.) from Day 10 to Day 37. The arthritis murine model was induced by injecting FCA into the ankle joints of hind limbs. The AA group, the AA + TET group, and the AA + DEX group mice were treated with PBS, tetrandrine (6 mg/kg), or dexamethasone (1 mg/kg) i.p. daily, respectively. Arthritic scores were evaluated, and the joint diameter was measured every three days. A cytometric bead assay was performed to measure the concentrations of IFN-γ, TNF-α, and IL-6 in the serum. H&E staining and Safranin O-fast staining were adopted to monitor the tissue changes in the joint. Immunohistochemistry assays were applied to detect the MPO, NE, CitH3, and PAD4 expression levels. To assess the effect of tetrandrine on neutrophil activities in vitro, CCK8 tests were applied to determine cell viability. The qPCR and ELISA were performed to determine IL-1β and IL-6 expression levels. Immunofluorescence assays were performed to measure the formation of NETs. The results indicated that tetrandrine significantly alleviated the symptoms of RA in terms of the ankle diameter (from 4.629 ± 2.729 to 3.957 ± 0.257; P < 0.01 ) and ankle score (from 4.000 ± 0.000 to 3.286 ± 0.756; P < 0.05 ). Tetrandrine treatment significantly increased the cartilage areas and decreased serum IL-6 significantly (from 5.954 ± 2.127 to 2.882 ± 2.013; P < 0.01 ). The immunohistochemistry assays also showed decreased expression levels of NE, MPO, PAD4, and CitH3 induced by tetrandrine in comparison with the AA group ( P < 0.01 ). The qPCR assays and ELISAs showed that tetrandrine had an anti-inflammatory effect in vitro by significantly inhibiting IL-6 ( P < 0.01 ). The immunofluorescence assays showed that NET formation induced by PMA could be reduced by tetrandrine ( P < 0.01 ). In conclusion, tetrandrine has good efficacy in treating RA by regulating neutrophil-involved inflammation and NET formation.

Three-dimensional (3D) network structure of metal–organic framework (MOF) can accommodate outstanding electrocatalysis performances, but always collapse during the conversion to active materials or applications process. How to maintain the 3D network when producing active species is of great importance for full application of MOF. Herein, a new MOF material, In[Co(CN)6] (In-Co PBA) nanocubes, are firstly synthesized. Through a controlled low-temperature deligandation process, the In-Co PBA nanocubes are transformed to a novel In2O3@In-Co PBA quasi-MOF nanocubes, which basically retain the 3D porous structure of PBA but with in situ generated In2O3 nanoparticles inside. When used as CO2RR electrocatalyst, such a novel cubic composite structure exhibits excellent performances with faradaic efficiency of 85% for formate at a potential of −0.96 V and with current density of 31.5 mA·cm−2 at −1.32 V, surpassing most of the reported indium-based catalysts. The excellent performance can be attributed to the special composite structure, which provides not only active sites by In2O3 nanoparticles to catalyze CO2RR, but also the 3D porous framework by quasi-MOF to accelerate gaseous exchange and electrolyte permeation and prevent the electrode choking. This work offers a new strategy for the design of post-transition metal catalysts and the structure design of quasi-MOF.

Modifying the separator of lithium-sulfur batteries (LSBs) is considered to be one of the most effective strategies for relieving the notorious polysulfide shuttle effect. Constructing a stable, lightweight, and effective LSB separator is still a big challenge but highly desirable. Herein, a stable and lightweight imide-based covalent organic framework (COF-TpPa) is facilely fabricated on reduced graphene oxide (rGO) through an oxygen-free solvothermal technique. With the directing effect of rGO and changing the side functional group of the monomer, the morphology and the pore tailoring of COF-TpPa can be simultaneously achieved and two-dimensional (2D) COF nanosheets with different functionalities (such as -SO

According to the assumption that the formation of C-Pd bond becomes a cyclopalladated complex (CPC), we designed and synthesized two C-N-N pincer ligands of BODIPY appended 2,2'-bipyridine derivatives (BP and BPB). It has been confirmed that the C-Pd bond does exist and plays a crucial role in "on-off" fluorescence behavior. Based on it, a coordination-induced fluorescence quenching sensor for Pd

Six novel donor–acceptor conjugated polymers were designed and synthesized by the Stille coupling reaction of triarylamine derivatives as donor units with isoindigo derivative or benzothiadiazole as acceptor units. These polymers have good solubility and film-forming properties in common organic solvents. The char yields of polymers in nitrogen atmosphere at 800 °C range from 34 to 60%. In particular, these conjugated polymers exhibit high photoluminescence (PL) quantum efficiency (up to 42.9%). These polymers demonstrate two pairs of redox peaks with low onset voltages (0.51 V vs. Ag/AgCl for P5) and narrow band gaps (Eg = 2.52 ~ 2.95 eV). The colors of all polymer films change significantly with the applied voltage increasing. Moreover, the polymers show high coloring efficiency (up to 163%) and maintain good electrochromic (EC) cycle stability over 500 s. In addition, excellent results in terms of memory storage (ON/OFF = 1.2 × 104), 2,4,6-Trinitrophenol (TNP) detection (Ksv = 45,790 M-1) can meet the requirements of multifunctional materials.

High-entropy materials have gained extensive attention owing to their unique structural characteristics and outstanding properties. The synthesis of high-entropy compounds, particularly high-entropy metal phosphides, has been seldom reported because of the incompatibility between different metals and non-metals. Herein, we propose a one-step low temperature sol–gel strategy to overcome the incompatibility and synthesize high-entropy metal phosphide (HEMP) NiCoFeMnCrP nanoparticles on a carbon matrix. Due to the synergistic effect among the metal elements, NiCoFeMnCrP exhibits supernormal catalytic activities for the oxygen evolution reaction (OER), hydrogen evolution reaction (HER) and overall water splitting. The fact that the overpotentials for the OER and HER decrease with the increase of the metal species number demonstrates that the realization of high entropy has great effects on performance enhancement. Our work provides a facile and viable synthesis strategy for preparing high entropy compounds which would offer great potential in energy and electrocatalysis applications by entropy engineering.

The design and synthesis of hollow-nanostructured transition metal oxide-based anodes is of great importance for long-term operation of lithium ion batteries (LIBs). Herein, a special hollow bowl-like α-Fe

Exploring cost-effective and general approaches for highly active and stable bifunctional transition metal phosphide (TMP) electrocatalysts towards overall water splitting is greatly desirable and challenging. Herein, a general strategy combining sol-gel and a carbonization-assisted route was proposed to facilely fabricate a series of TMP nanoparticles, including CoP, MoP, FeP, Cu2P, Ni2P, PtP2, FeNiP, CoNiP, and FeCoNiP, coupled in an amorphous carbon matrix with one-step carbon composite formation. The resultant NiFeP@C exhibits excellent activities as a bifunctional electrocatalyst toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) with low overpotentials of 260 and 160 mV, respectively, at 10 mA/cm2 in 1 M KOH solution. With the NiFeP@C electrocatalyst as both electrode materials, an integrated electrolyzer can deliver 47.0 mA/cm2 of current density at 1.60 V, better than the assembled Pt/C20∥IrO2 counterpart. The encapsulation of NiFeP nanoparticles in the carbon matrix effectively prevents their corrosion and leads to almost unfading catalytic activities for more than 20 h for either the HER, OER, or overall water splitting, outperforming recently reported bifunctional electrocatalysts. The coexistence of Ni, Fe, P, and C would have synergetic effects to accelerate charge transfer and promote electrocatalytic activity. This universal strategy for TMP-based composites opens up a new avenue to explore TMPs as multifunctional materials for various applications.

It is a challenging task to seek a highly-efficient electrocatalyst for oxygen evolution reaction (OER) of water splitting. Non-noble Co-based nanomaterials are considered as earth-abundant and effective catalysts to lower overpotential and increase polarization current density of OER. In this work, we reported, for the first time, a “rapid solvent-evaporation” strategy for the synthesis of three-dimensional (3D) cobalt complex hierarchical architectures constructed by two-dimensional (2D) nanosheets. The 3D structured cobalt complexes have excellent performances in catalyzing OER with lower onset potential, overpotential, Tafel slope and better stability than commercial IrO2. Superior electrochemical performances would be beneficial from the unique 3D structure. This extremely simple method for 3D Co complex with good OER activities makes the complex be promising commercial OER catalyst to replace earth-rare and expensive IrO2.

NiFe alloy catalysts have received increasing attention due to their low cost, easy availability, and excellent oxygen evolution reaction (OER) catalytic activity. Although it is considered that the co-existence of Ni and Fe is essential for the high catalytic activity, the identification of active sites and the mechanism of OER in NiFe alloy catalysts have been controversial for a long time. This review focuses on the catalytic centers of NiFe alloys and the related mechanism in the alkaline water oxidation process from the perspective of crystal structure/composition modulation and structural design. Briefly, amorphous structures, metastable phases, heteroatom doping and in situ formation of oxyhydroxides are encouraged to optimize the chemical configurations of active sites toward intrinsically boosted OER kinetics. Furthermore, the construction of dual-metal single atoms, specific nanostructures, carbon material supports and composite structures are introduced to increase the abundance of active sites and promote mass transportation. Finally, a perspective on the future development of NiFe alloy electrocatalysts is offered. The overall aim of this review is to shed light on the exploration of novel electrocatalysts in the field of energy., Effective strategies to increase the intrinsic activity by electronic modulation and to increase the number of active sites by structural design are discussed for improving the oxygen evolution activities of NiFe alloys.

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is known as a rare disease characterized by inflammatory lesions on bones and skin. Polymorphism of clinical manifestation and lack of molecular biomarkers have both limited its diagnosis. Our study performed RNA sequencing (RNA-seq) and integrative bioinformatics analysis of long noncoding RNA (lncRNA)-messenger RNA (mRNA) profile in patients with SAPHO syndrome and healthy controls. A total of 4,419 differentially expressed (DE) mRNAs and 2,713 lncRNAs were identified (p < 0.05, fold change > 2) and a coexpression network was constructed to further investigate their regulatory interactions. The DE lncRNAs were predicted to interact with mRNAs in both cis and trans manners. Functional prediction found that the lncRNA-targeted genes may function in SAPHO syndrome by participating in biological process such as adipocytokine signaling pathway, ErbB signaling pathway, FoxO signaling pathway, as well as production and function of miRNAs. The expression levels of three pairs of coexpressed lncRNA-mRNAs were validated by qRT-PCR, and their relative expression levels were consistent with the RNA-seq data. The deregulated RNAs GAS7 and lnc-CLLU1.1-1:2 may serve as potential diagnostic biomarkers, and the combined receiver operating characteristic (ROC) curve of the two showed more reliable diagnostic ability with an AUC value of 0.871 in distinguishing SAPHO patients from healthy controls. In conclusion, this study provides a first insight into long noncoding RNA transcriptome profile changes associated with SAPHO syndrome and inspiration for further investigation on clinical biomarkers and molecular regulators of this inadequately understood clinical entity.

Palladium (Pd) is regarded as a potential non-platinum electrocatalyst to drive oxygen reduction in fuel cells. The development of Pd-based electrocatalysts with high performances through structural engineering is still highly desirable. Herein, a facile one-pot synthesis strategy with the assistance of dual surface protecting agents was developed to fabricate carbon-supported Pd (Pd/C) nanodendrites with high mesoporosity. The mesoporous spherical Pd/C nanodendrites are built with connected nanoparticles with a small size of several nanometers and coated by simultaneously formed carbon layers. The used dual protecting agents, glycine and oleylamine, exhibit synergistic effects to engineer Pd growth to form the unique mesoporous dendritic structure. Benefiting from the mesoporous feature, small size, defect-rich surface and carbon coating, the obtained mesoporous Pd/C nanodendrites exhibit great electrocatalytic performance toward the oxygen reduction reaction (ORR).

Rheumatoid arthritis (RA) is a chronic, systemic, synovitis-based inflammatory disease with unknown etiology. Neutrophils play important roles in the pathogenesis of RA. Apoptosis and NETosis of neutrophils are two major mechanisms of programmed cell death that differ in their morphological characteristics and effects on the immune system. In rheumatoid arthritis, delayed neutrophil apoptosis amplifies the inflammatory response; and massive release of NETs and their components may cause tissue damage and provide self-antigens. Emodin is a natural anthraquinone derivative that occurs in many widely used Chinese medicinal herbs. In this study, we evaluated the effect of emodin on a murine adjuvant-induced arthritis (AA) model of RA in vivo and on neutrophil apoptosis and NETosis in vitro. Our results show that emodin alleviated AA by reducing neutrophil infiltration and proinflammatory cytokine (interleukin-6, interferon-gamma and tumor necrosis factor-α) release. Emodin promoted apoptosis and inhibited autophagy and NETosis in neutrophils. These findings indicate that emodin represents a potential therapeutic agent for RA.

Hollow nanostructures with large surface area and additional free volume enable increasing contacting area and structure stability, beneficial to improve photocatalytic and lithium storage performances. Although successes have been achieved for spherical and cubic hollow structures, it is still a big challenge to prepare hollow materials with special structures. Herein we report a facile templated route for novel three-dimensional titanium dioxide tube-in-tube superstructures (TTS) with α-Fe2O3 hollow prisms as removable templates. The novel TiO2 TTS exhibit an obvious enhancement in photocatalysis to decompose rhodamine B under simulated sunlight compared with commercial TiO2 and TiO2 nanospheres. As anode material for LIB, the achieved sample delivers a high specific capacity of about 150 mAh·g−1 over 500 cycles, outperforming most of TiO2-based anode materials. These outstanding multifunction performances can be attributed to the unique tube-in-tube superstructures with large surface area and many active sites.

Four novel multifunctional electrochromic materials (PTT, PDTT, PNT and PDNT) based on tetraphenylethylene (TPE) and triphenylamine (TPA) units by Stille coupling reaction were prepared. Electrochemical impedance spectroscopy (EIS) measurements found that four polymers had low resistance values which improved their electrochemical and electrochromic properties. In addition, the maximum coloration efficiency (CE; η) value is 126 cm2/C at 1246 nm of PDTT, bleaching and coloring response times are 2.6 s and 1.6 s, respectively. There is no significant change of performance after a 100 cycle scanning. In addition to their excellent electrochromic properties, they also exhibit a strong aggregation-induced emission (AIE) effect. Furthermore, the fluorescence color of PDNT changed from bright green to black when voltage was applied from 0.0 to 1.6 V. Four polymers responded rapidly to light and they maintained stability over a 1000 s cycle.

Domestication of a transposon (a DNA sequence that can change its position in a genome) to give rise to the RAG1–RAG2 recombinase (RAG) and V(D)J recombination, which produces the diverse repertoire of antibodies and T cell receptors, was a pivotal event in the evolution of the adaptive immune system of jawed vertebrates. The evolutionary adaptations that transformed the ancestral RAG transposase into a RAG recombinase with appropriately regulated DNA cleavage and transposition activities are not understood. Here, beginning with cryo-electron microscopy structures of the amphioxus ProtoRAG transposase (an evolutionary relative of RAG), we identify amino acid residues and domains the acquisition or loss of which underpins the propensity of RAG for coupled cleavage, its preference for asymmetric DNA substrates and its inability to perform transposition in cells. In particular, we identify two adaptations specific to jawed-vertebrates—arginine 848 in RAG1 and an acidic region in RAG2—that together suppress RAG-mediated transposition more than 1,000-fold. Our findings reveal a two-tiered mechanism for the suppression of RAG-mediated transposition, illuminate the evolution of V(D)J recombination and provide insight into the principles that govern the molecular domestication of transposons. Identification of the changes that converted a transposase to a recombinase sheds light on the evolution of the vertebrate adaptive immune system.

Multiple stimuli-responsive smart polymers have received increasingly attention in recent years. In this work, a series of novel polyimides (PIs) bearing triarylamine and naphthalimide perssad were devised and prepared. These novel polyimides are able to respond to four different stimuli (light, pH, explosives and voltage) and perform four functions (light detectors, electrochromism, fluorescence detectors and memory devices). Furthermore, the smart materials are suitable for complicated environment. This work will open a new route for the development of novel smart materials with multi-functional and multiple stimuli-responsive properties.

In this work, a series of multifunctional polyurethane (PU) materials containing three kinds of different triarylamine (TAA) units was prepared. These polymers show good solubility in common organic solvents and excellent thermal stability under a N2 atmosphere. The PU films show reversible color changes with high contrast ratios and electrochromic stability. Moreover, they have good memory storage performance. The ON/OFF current ratio is about two orders of magnitude. Meanwhile, they can be used as detectors for 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP). The polymer solutions rapidly exhibit fluorescence-quenching phenomena when exposed to trace amounts of TNT and TNP. The PU films also have mechanical properties that make them suitable for use in stretchable devices.

A multifunctional integrated platform based on conjugated oligomers containing novel triarylamine (TAA) and fluorene units with responding to voltage, light and explosives stimuli and performing for sensors, detectors, memory media and high contrast displays was designed, and the stimuli-responsive mechanisms were studied. These oligomers show excellent thermal stability with no significant weight loss below 350 °C in nitrogen atmosphere. During the electrochemical reoxidation process, the oligomer films exhibit two pairs of obvious redox peaks with the strong color changes from yellowish of neutral state to green and blue of oxidized state, and remain good continuous cyclic stability over 500s with a cycle time of 10s. The electrofluorescent properties of the oligomers also can be tuned by electrochemistry redox, exhibiting high contrast. Meanwhile, non-volatile rewritable flash memory devices were produced with the sandwich structure ITO/oligomer/Al, which could gain the ON/OFF current ratio as high as about 104 at low threshold voltage of 1.2 V.

We report here that a series of novel donor-acceptor (D–A) conjugated polymers based on isoindigo were synthesized and characterized. As novel electrochromic materials, their optical and electrochemical properties have been investigated. Cyclic voltammograms (CV) of the polymer films exhibit two pairs of obvious redox peaks in the range of 0.76–1.80 V with strong color changes in the visible and near infrared (NIR) regions. The coloring and bleaching time are in the range of 3.5–4.9 s and 4.4–5.0 s, respectively. The amount of char yield at 800 °C in nitrogen for polymers was in the range of 56–64%. Especially, the polymers show strong fluorescence with a fluorescence quantum efficiency (ФPL) of up to 32.5% which is reported firstly. In addition, memory properties, explosive detection and photoelectric properties for polymers are studied which indicating promising results.

A series of alternate copolymers D‑co‑Ts named P(DPP‑TA) P(DPP‑Cz) and P(DPP‑DB) consisting of both diketopyrrolopyrrole (DPP) and different triarylamine (TAA) units, were synthesized by Stille cross-coupling reaction in which DPP acts as an acceptor and TAA acts as a donor. These D‑co‑Ts show good thermal stability in nitrogen (N2) atmosphere. The solutions of D‑co‑Ts have strong UV–vis absorption bands in the range of 313 nm to 344 nm and have fluorescence (PL) peaks at from 415 nm to 496 nm with high quantum efficiency. The highest occupied molecular orbital (HOMO), lowest unoccupied molecular orbital (LUMO) energy levels and Eg were combined with via cyclic voltammograms (CV) as −5.19 eV to −5.41 eV, −3.77 eV to −3.80 eV, and 1.42 eV to 1.62 eV, respectively. The P(DPP‑TA) film shows the evident color changes from original yellow to brownish to blue. New absorption peaks of P(DPP‑TA) appear at 412 nm and 938 nm with increasing voltage in the UV–vis spectrophotometer, indicating D‑co‑Ts can be promising electrochromic materials. The highest coloration efficiency reaches up to be 270 cm2 C−1 for the P(DPP‑Cz). The memory performances of the ITO/polymer/Al sandwich devices were also studied, in which D‑co‑Ts exhibit the typical nonvolatile rewritable flash memory characteristics. The device of P(DPP‑DB) shows an ON/OFF current ratio of 5.80 × 104 under a threshold voltage of −1.80 V. Furthermore, in the explosive detection tests, the copolymer shows new emission band at 570 nm with addition of TNT, and the PL quenching efficiency goes up to be 82%.

Hollow nanoframes with three-dimensional open architecture have diverse applications but their acquirement is still a big challenge. Herein, a crystal morphological evolution mechanism is proposed for the synthesis of dodecahedral [Co(CN)6]3-@POMs (polyoxometalates) frame-like nanostructure. Through an inside-out etching process, K3PW12O40 (POMs) dodecahedron are transformed to dodecahedral POMs nanoframes with encapsulation of [Co(CN)6]3- inside the nanochannels, which can be transformed to Co, N, C co-doped POMs nanoframes (CNCP) by a further N2-pyrolysis process. The hybrid nanoframes possess unique yolk-shell structure with multi-heteroatoms doping, showing great advantages for oxygen evolution reaction (OER). As an OER catalyst, it exhibits excellent electrochemical catalytic activities with a low overpotential of 241 mV at 10 mA cm−2, a small Tafel slope of 75.8 mV dec-1 and a long-term electrochemical stability. Our work not only provides novel dodecahedral Keggin-type polyoxometalates yolk-shell structure and nanoframes, but also provides a facile strategy to in situ encapsulate active components inside porous substrates, and thus will open a new perspective for the further utilization of POMs nanomaterials as potential catalysts for energy storage and conversion.