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CsPbI3perovskite-based phosphors are ideal candidates for red/near-infrared light-emitting diodes (LEDs). However, they suffer from poor stability and low photoluminescence quantum yields (PLQYs). Herein, CsPbI3@zeolite composites with bright, deep-red, solid-state fluorescence have been successfully developed by a high-temperature calcination followed by water treatment strategy. The composites possess PLQYs of 31.1% and exceptional stability even comparable to that of commercial phosphors. Such properties are rarely reported in solid-state CsPbI3perovskite systems. Studies show that removing the non-luminous by-products and controlling the thickness of the zeolite shell are essentials for enhancing the PLQYs, and the excellent stability results from the tight encapsulation of CsPbI3perovskite by the host skeleton. As a proof of concept, standard red and white LEDs with a maximal luminous efficiency of 57.3 lm/W and excellent long-term operation stability are constructed based on the as-made composites. This work unlocks the application potential of CsPbI3perovskite as stable red phosphors.

Ultrasmall CsPbBr3perovskite quantum dots (PQDs) as promising blue-emitting materials are highly desired for full-color display and lighting applications, but their inferior efficiency and poor ambient stability hinder extensive applications. Herein, a “break-and-repair” strategy has been developed to tightly confine monodispersed ultrasmall CsPbBr3PQDs in a zeolite. In this strategy, the CsPbBr3PQDs are introduced into the zeolite viaa high temperature evaporation method, wherein the perovskite precursors break the zeolite framework, and amino acids and silane are then used to fix the damaged framework and lock the perovskite QDs within the matrix. By modulating the synthetic conditions to control the growth of CsPbBr3, PQDs with ultrasmall size of 2 nm have been obtained in the zeolite, giving emission centered at 460 nm with a high quantum yield of 76.93%. Strikingly, the PQDs@zeolite composite exhibits water-induced reversible photoluminescence promoted by the coordination between the amino acids and PQDs in a dynamic manner, achieving enhanced water stability (14 days in aqueous solution). This work provides a new perspective for the synthesis of water-stable blue-emitting perovskite composites for potential applications in lighting fields.

Controlling the enzymatic reaction of macromolecules in living systems plays an essential role in determining the biological functions, which remains challenging in the synthetic system. This work shows that host–guest complexation could be an efficient strategy to tune the enzymatic self-assembly of the peptide. The formed host–guest complexation prevents the enzymatic kinetics of peptide assemblies on the cell surface and promotes cellular uptake of assemblies. For uptake inside cells, the host–guest complex undergoes dissociation in the acidic lysosome, and the released peptide further self-assembles inside the mitochondria. Accumulating assemblies at mitochondria induce the ferroptosis of cancer cells, resulting in cancer cell death in vitroand the tumor-bearing mice model. As the first example of using host–guest complexation to modulate the kinetics of enzymatic self-assembly, this work provides a general method to control enzymatic self-assembly in living cells for selective programming cancer cell death.

ABSTRACTVaccine hesitancy is a major obstacle to the achievement of universal child vaccination, which has been studied extensively in Western countries but much less so in Asian countries, especially China. This cross-sectional survey is aimed to assess the prevalence of vaccine hesitancy and to explore the reasons for vaccine hesitancy among parents in Guangzhou. In January 2020, a questionnaire adapted to the Chinese setting from a widely-used hesitancy scale was administered to a sample of parents who brought their children aged <13 years to Community Health Service Centers for vaccination in Guangzhou. The incidence of vaccine hesitancy among those parents was 6.6% (50/755). Regression analysis showed that differences in socio-economic characteristics were not associated with the occurrence of vaccine hesitancy among parents in Guangzhou. However, strong distrust of domestic vaccine quality (OR = 10.9, 95% CI = 1.5–81.4), being required to have their children vaccinated for nursery and school entry (OR = 3.6, 95% CI = 1.7–7.7), and not being aware of which vaccines are officially required and which are optional (OR = 2.1, 95% CI = 1.1–4.3) were the risk factors significantly associated with vaccine hesitancy. In order to increase parents’ trust in domestic vaccine quality and reduce the prevalence of vaccine hesitancy, it is essential to strengthen quality control in domestic vaccine manufacturing and to proactively disseminate clear and accurate information about vaccines to parents. Furthermore, advocating the value of vaccination among all citizens of Guangzhou is crucial.

Immune reactions are a key factor in determining the destiny of bone substitute materials after implantation. Macrophages, the most vital factor in the immune response affecting implants, are critical in bone formation, as well as bone biomaterial-mediated bone repair. Therefore, it is critical to design materials with osteoimmunomodulatory properties to reduce host-to-material inflammatory responses by inducing macrophage polarization. Our previous study showed that calcium silicate (CS) bioceramics could significantly promote osteogenesis. Herein, we further investigated the effects of CS on the behavior of macrophages and how macrophages regulated osteogenesis. Under CS extract stimulation, the macrophage phenotype was converted to the M2 extreme. Stimulation by a macrophage-conditioned medium that was pretreated by CS extracts resulted in a significant enhancement of osteogenic differentiation of bone marrow mesenchymal stem cells (BMSCs), indicating the important role of macrophage polarization in biomaterial-induced osteogenesis. Mechanistically, oncostatin M (OSM) in the macrophage-conditioned medium promoted osteogenic differentiation of BMSCs through the ERK1/2 and JAK3 pathways. This in vivostudy further demonstrated that CS bioceramics could stimulate osteogenesis better than β-TCP implants by accelerating new bone formation at defective sites in the femur. These findings improve our understanding of immune modulation of CS bioactive ceramics and facilitate strategies to improve the in vitroosteogenesis capability of bone substitute materials.

Carbon dots (CDs) with red-emitting room-temperature phosphorescence (RTP) are rarely reported because of the increasing nonradiative decay of the excited states and the decreasing energy gap between the excited states and ground states. Herein, we demonstrate a facile strategy for modulating the RTP properties of CDs in terms of donor–acceptor energy transfer (EnT) in the CDs-in-zeolite system. Upon tuning of the heteroatoms (Zn2+, Mn2+) doped in the aluminophosphate zeolite frameworks, CDs@zeolite composites with green and red phosphorescence have been prepared via in situ hydrothermal synthesis. In such composites, the zeolite matrix provides an efficient confinement role in stabilizing the triplet states of CDs. Significantly, the Mn-doped zeolite could act as an energy acceptor allowing EnT from excitons of CDs to the dopant in the host matrix, generating the intriguing red RTP behavior. This work provides an effective strategy for developing CD-based composite materials with special RTP emissions as well as new fields for applications.

The study was performed to determine the complication and recurrence rate using the modified Kugel oval patch for small ventral hernia repair. Another aim of the study was to find risk factors for recurrence in patients with this repair. Seventy-three patients underwent ventral hernia repair with the modified Kugel oval patch between April 2013 and February 2015. Prospective follow-up data (18 months postoperative) were collected and evaluated. A total of 58 primary (18 epigastric/40 umbilical) and 15 incisional ventral hernias were repaired with the modified Kugel oval patch (7.6/10.2 cm/8 x 12 cm). We found three patients suffered superficial wound infection and two participants got hernia recurrence. Placement of mesh was found to be a significant risk factor for hernia recurrence. Small ventral hernia repair using the modified Kugel oval patch is a novel and useful approach and we recommend placing the patch preperitoneally.

ABSTRACTBackground: To investigate the expression of endothelin receptors in liver diseases and discuss its role in the process of liver cirrhosis and liver cancer.Research design and methods: We examined the expressions of ETAR, ETBR and α-SMA in tissue samples using western blotting analysis. Furthermore, immunofluorescence was used to locate ETAR expression in hepatic stellate cells (HSCs) and hepatic sinusoidal endothelial cells (HSECs), we calculated the percentage of positive cells and then analyzed its relation with clinical indexes.Results: According to the western blotting analysis, the expression of ETAR was high in hepatic hemangioma and liver cancer tissues and ETBR was highly expressed in cirrhosis tissues. The immunofluorescence results demonstrated that the expression of ETAR was elevated in hepatic hemangioma and liver cancer tissues. Moreover, ETAR expression was found in both HSCs and HSECs. Finally, the statistical analysis revealed that the number of positive ETAR cells was correlated with the clinical index platelets (PLT), alanine transaminase (ALT) and diameter of portal vein.Conclusion: Endothelin receptors express differently in liver cirrhosis and liver cancer tissues and play a role in hepatic diseases by affecting HSCs and HSECs.

Cells use dynamic self-assembly to construct functional structures for maintaining cellular homeostasis. However, using a natural biological small molecule to mimic this phenomenon remains challenging. This work reports the dynamic microfiber formation of nucleopeptide driven by guanosine triphosphate, the small molecule that controls microtubule polymerization in living cells. Deactivation of GTP by enzyme dissociates the fibers, which could be reactivated by adding GTP. Molecular dynamic simulation unveils the mystery of microfiber formation of GBM-1and GTP. Moreover, the microfiber formation can also be controlled by diffusion-driven GTP gradients across a semipermeable membrane in bulk conditions and the microfluidic method in the defined droplets. This study provides a new platform to construct dynamic self-assembly materials of molecular building blocks driven by GTP.

Ectopic expression of the HarpinXooc–encoding gene hrf2in rapeseed (Brassica napusL.) confers enhanced resistance to Sclerotinia sclerotiorumand improved agronomic performance. To better understand the molecular mechanisms of harpin‐mediated plant responses, we developed a 3’–tag digital gene expression (DGE) method to compare the mRNA expression patterns of transgenic T‐4 rapeseed harboring hrf2and untransformed Yangyou 4 (Y4) at the global level. Solexa Illumina sequencing yielded 5,645,091 and 6,007,037 clean tags, corresponding to 14,237 and 14,773 genes for Y4 and T‐4, respectively. We identified 2114 differentially expressed genes (DEGs; log2 ratio ≥ 1, false discovery rate [FDR] ≤ 0.001) between transgenic T‐4 and untransformed Y4 that assigned to seven Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways and 19 Gene Ontology categories. Numerous genes related to defense responses were differentially expressed in T‐4, representing categories such as hypersensitive response, defense proteins, plant cell wall components, and phenylpropanoid metabolism pathway. Furthermore, expression was largely modified in T‐4 in signaling pathways including G protein, Ca2+, ubiquitination, protein kinase, salicylic acid, jasmonic acid, abscisic acid, ethylene, and auxin hormones. We also identified numerous DEGs encoding transcription factors in T‐4. This analysis shows the breadth of molecular mechanisms of harpin‐mediated plant responses in genetically transformed plants. Furthermore, the DGE sequence resources identified in this study provide a platform for functional genomics studies of rapeseed.

Anisotropic structures made by hierarchical self-assembly and crystallization play an essential role in the living system. However, the spontaneous formation of liquid crystalline hydrogel of low molecular weight organic molecules with controlled properties remains challenging. This work describes a rational design of tetrapeptide without N-terminal modification and chemical conjugation that utilizes intermolecular interactions to drive the formation of nanofiber bundles in a two-component system, which could not be accessed by a single component. The diameter of nanofibers can be simply controlled by varying the enantiomer of electrostatic pairs. Mutation of lysine (K) to arginine (R) results in an over 30-fold increase of mechanical property. Mechanistic studies using different techniques unravel the mechanism of self-assembly and formation of anisotropic liquid crystalline domains. All-atom molecular dynamics simulations reveal that the mixture of heterochiral peptides self-assembles into a nanofiber with a larger width compared to the homochiral assemblies due to the different stacking pattern and intermolecular interactions. The intermolecular interactions show an obvious increase by substituting the K with R, facilitating a more stable assembly and further altering the assembly mechanics and bulk material properties. Moreover, we also demonstrated that the hydrogel properties can be easily controlled by incorporating a light-responsive group. This work provides a method to generate the liquid crystalline hydrogel from isotropic monomers.

A robust detection scheme for detecting and identifying faulty actuators via unknown input observers is proposed. In this scheme, the uncertainties and some inputs are regarded as unknown inputs. A bank of unknown input observers are thus constructed, each of which is driven by all inputs but one. The residuals of these observers arc used lo construct the detection and identification logic. Simulations based on a non-linear chemical reactor with heat exchanger illustrate the validity of the proposed method. Moreover, a component failure detection scheme via an unknown input observer is also proposed.

In this paper, linear systems with failures is described as a linear state equation with bias, the failure is expressed by a abrupt change of bias, A modified separated-bias estimation method for failure detection and estilation is proposed by combining the separated-bias estimation method and the statistical decision principle. This method is very simple and the prior knowledge about failures is not necessary. The simulation results show that this method can reliablely detect the failure and accuratelyestimate the failure magnitude.

This work reports the efficient polymerization of 4-vinylpyridine (4VP) using Lewis pairs composed of homoleptic rare-earth (RE) aryloxides and ylide-functionalized phosphines (YPhos). The resultant P4VP was readily quaternized by the addition of 1-bromododecane. Polymerization of 4VP derivatives (2-methoxy-4-vinylpyridine, 4-vinylquinoline, and 2,6-dimethyl-4-vinylpyridine) also occurred under identical reaction conditions. The RE/YPhos Lewis pair polymerization system effectively copolymerized 4VP with methyl methacrylate, which resulted in copolymers with gradient architectures and narrow molecular weight distributions. A combined experimental and computational study provided critical insights into the polymerization mechanism. Density functional theory calculations also revealed that the use of YPhos as a Lewis base greatly facilitated both the initiation and subsequent monomer insertion in comparison with PEt3.