Interfacial Wrinkling Structures Based on a Double Cross-Linking Strategy Enable a Dual-Mode Optical Information Encryption.

Surface wrinkling structures based on a bilayer system are widely employed in storing and encrypting specific optical information. However, constructing a stable wrinkling structure with high-level security remains an extensive challenge due to the delamination issue between the skin layer and the substrate. Herein, a double cross-linking strategy is introduced between a hydrogel layer doped with fluorescent molecules and polydimethylsiloxane to establish a stable interfacial wrinkling structure with dual-mode functionality, in which the light reflection of the wrinkles and fluorescence intensity of fluorescent molecules can be simultaneously regulated by the modulus ratio between the two layers. The spontaneous wrinkling structures with a physically unclonable function can enhance the photoluminescence emission intensity of the wrinkling area under ultraviolet radiation. Meanwhile, the skin layer constructed of acrylamide and acrylic acid copolymer protects the interfacial wrinkling patterns from the loss of a detailed structure for authentication due to external damage. The stable interfacial wrinkling structures with fluorescence can find potential applications in the fields of information storage and encryption.

Designed wrinkles for optical encryption and flexible integrated circuit carrier board.

Patterns on polymers usually have different mechanical properties as those of the substrates, causing deformation or distortion and even detachment of the patterns from the polymer substrates. Herein, we present a wrinkling strategy, which utilizes photolithography to define the area of stress distribution by light-induced physical crosslinking of polymers and controls diffusion of residual solvent to redistribute the stress and then offers the same material for patterns as substrate by thermal polymerization, providing uniform wrinkles without worrying about force relaxation. The strategy allows the recording and hiding of up to eight switchable images in one place that can be read by the naked eye without crosstalk, applying the wrinkled polymer for optical anti-counterfeiting. The wrinkled polyimide film was also utilized to act as a substrate for the creation of fine copper circuit by a full-additive process. It generates flexible integrated circuit (IC) carrier board with copper wire density of 400% higher than that of the state-of-the-art in industry while fulfilling the standards for industrialization.

Viscoelasticity­Controlled Relaxation in Wrinkling Surface for Multistage Time­Resolved Optical Information Encryption.

As counterfeit techniques continue to evolve, ensuring the security of conventional "static" encryption methods becomes increasingly challenging. Here, the viscoelasticity-controlled relaxation is introduced for the first time in a bilayer wrinkling system by regulating the density of hydrogen bond networks in polymer to construct a "dynamic" encryption material. The wrinkling surface can manipulate light during the dynamic relaxation process, exhibiting three stages with frosted glass, structural color, and mirror reflection. By regulating the viscoelasticity of skin layer through UV irradiation, the wavelength and the relaxation rate of the wrinkles can be controlled. As a result, dynamic wrinkling anti-counterfeiting patterns and time-resolved multistage information encryption are achieved. Crucially, the encryption material is developed as an anti-counterfeiting label for packing boxes in daily applications, allowing the encrypted information to be activated manually and identified by naked eyes, surpassing the existing time-resolved encryption materials in utilization potential. Besides, the dynamic hydrogen bond networks are extended to various dynamic interaction networks, demonstrating the versatility of the dynamic encryption strategy. This work not only provides an additional dimension for dynamic information encryption in daily practical use, but also offers theoretical guidance for the development of advanced optical anti-counterfeiting and smart display materials in the future.

Preoperative Virtual Reduction Planning Algorithm of Fractured Pelvis Based on Adaptive Templates.

OBJECTIVE: The minimally invasive treatment of pelvic fractures is one of the most challenging trauma orthopedics surgeries, where preoperative planning is crucial for the performance and outcome of the surgery. However, planning the ideal position of fragments currently relies heavily on the experience of the surgeon. METHODS: A pelvic fracture virtual reduction algorithm for target position is provided based on statistical shape models (SSM). First, according to sexual dimorphism, pelvic SSM based on point cloud curvature down-sampling are constructed as adaptive templates. Then, an optimization algorithm is designed to iteratively adjust the target pose of the fragments and the adaptive matching of the templates. Finally, the feasibility of the method is verified by simulating fractures and clinical data. RESULTS: The pelvis has complex shape characteristics, which can be analyzed by SSM to clearly understand the pattern of change. Experiments showed that the SSM-based pelvic fracture reduction method had translation and rotation errors of 2.20±1.09 mm and 3.16±1.26° in simulated cases, and 2.78±0.95 mm and 3.10±0.53° in clinical cases, which has higher accuracy than methods based on mean shape models, and wider applicability than methods based on pelvic symmetry. CONCLUSION: The pelvic digital model created by SSM has good generalization properties, and the SSM-based virtual reduction algorithm can effectively reconstruct the target position of the fractured pelvis in preoperative planning. SIGNIFICANCE: The proposed reduction method has the characteristics of high precision and wide application range, which provides a powerful tool for the surgeon's virtual preoperative planning.

Pencil-like Hollow Carbon Nanotubes Embedded CoP-V4P3 Heterostructures as a Bifunctional Catalyst for Electrocatalytic Overall Water Splitting.

Electrocatalytic water splitting is one of the most efficient ways of producing green hydrogen energy. The design of stable, active, and efficient electrocatalysts plays a crucial role in water splitting for achieving efficient energy conversion from electrical to hydrogen energy, aimed at solving the lingering energy crisis. In this work, CNT composites modified with CoP-V4P3 composites (CoVO-10-CNT-450P) were formed by carbonising a pencil-like precursor (Co3V2O8-H2O) and growing carbon nanotubes in situ, followed by in situ phosphorylation on the carbon nanotubes. In the HER electrocatalytic process, an overpotential of only 124 mV was exhibited at a current density of 10 mA cm-2. In addition, as an OER catalyst, a low overpotential of 280 mV was attained at a current density of 10 mA cm-2. Moreover, there was no noticeable change in the performance of the catalyst over a 90 h test in a continuous total water splitting experiment. The unique electronic structure and hollow carbon nanotube structure of CoVO-10-CNT-450P effectively increased the catalytic active sites, while also significantly improving the electrocatalytic activity. This work provides theoretical guidance for the design and synthetic route of high-performance non-precious metal electrocatalysts, and actively promotes the commercial application of electrochemical water splitting.

Prior information-based high-resolution tomography image reconstruction from a single digitally reconstructed radiograph.

Tomography images are essential for clinical diagnosis and trauma surgery, allowing doctors to understand the internal information of patients in more detail. Since the large amount of x-ray radiation from the continuous imaging during the process of computed tomography scanning can cause serious harm to the human body, reconstructing tomographic images from sparse views becomes a potential solution to this problem. Here we present a deep-learning framework for tomography image reconstruction, namely TIReconNet, which defines image reconstruction as a data-driven supervised learning task that allows a mapping between the 2D projection view and the 3D volume to emerge from corpus. The proposed framework consists of four parts: feature extraction module, shape mapping module, volume generation module and super resolution module. The proposed framework combines 2D and 3D operations, which can generate high-resolution tomographic images with a relatively small amount of computing resources and maintain spatial information. The proposed method is verified on chest digitally reconstructed radiographs, and the reconstructed tomography images have achieved PSNR value of 18.621 ± 1.228 dB and SSIM value of 0.872 ± 0.041 when compared against the ground truth. In conclusion, an innovative convolutional neural network architecture is proposed and validated in this study, which proves that there is the potential to generate a 3D high-resolution tomographic image from a single 2D image using deep learning. This method may actively promote the application of reconstruction technology for radiation reduction, and further exploration of intraoperative guidance in trauma and orthopedics.

Anionic donor-acceptor conjugated polymer dots/g-C3N4 nanosheets heterojunction: High efficiency and excellent stability for co-catalyst-free photocatalytic hydrogen evolution.

Herein, we have assembled an anionic donor-acceptor (D-A) conjugated polyelectrolyte dots (Pdots), based on bithiophene units-containing backbone and sulfonate modified side chain (PCP-2F-Li), with porous g-C3N4 nanosheets (CNNS) into a new 0D/2D heterojunction (PCP-2F-Li Pdots/CNNS). The well-matched energy levels of PCP-2F-Li and CNNS and the strong electron-donating sulfinates in PCP-2F-Li can significantly accelerate the interfacial electron transfer in heterojunction, while the strong hydrophilicity of PCP-2F-Li can improve the interface wetting and promote the photocatalytic water-splitting. As such, PCP-2F-Li Pdots/CNNS can be used for efficient co-catalyst-free water splitting with a hydrogen evolution rate (HER) of 1932.1 µmol·h-1·g-1 over 6 runs, which is 1.85 and 2.29 times of hydrophobic F8T2 Pdots/CNNS and Pt-assisted CNNS, respectively. The apparent quantum yield (AQY) of PCP-2F-Li Pdots/CNNS can reach 7.87 %, 7.73 % and 5.60 % at 420, 450 and 475 nm, respectively. The findings highlight a new type of the Pdots-assisted heterojunctions for high-efficiency and durable co-catalyst-free water splitting.

Preparation of Flame-Retardant Polyurethane and Its Applications in the Leather Industry.

As a novel polymer, polyurethane (PU) has been widely applied in leather, synthetic leather, and textiles due to its excellent overall performance. Nevertheless, conventional PU is flammable and its combustion is accompanied by severe melting and dripping, which then generates hazardous fumes and gases. This defect limits PU applications in various fields, including the leather industry. Hence, the development of environmentally friendly, flame-retardant PU is of great significance both theoretically and practically. Currently, phosphorus-nitrogen (P-N) reactive flame-retardant is a hot topic in the field of flame-retardant PU. Based on this, the preparation and flame-retardant mechanism of flame-retardant PU, as well as the current status of flame-retardant PU in the leather industry were reviewed.

Capturing Visible Light in Low-Band-Gap C4 N-Derived Responsive Bifunctional Air Electrodes for Solar Energy Conversion and Storage.

We report facile synthesis of low-band-gap mesoporous C4 N particles and their use as responsive bifunctional oxygen catalysts for visible-light-sensitive (VLS) rechargeable Zn-air battery (RZAB) and polymer-air battery (RPAB). Compared to widely studied g-C3 N4 , C4 N shows a smaller band gap of 1.99 eV, with a larger photocurrent response, and it can function as visible-light-harvesting antenna and bifunctional oxygen reduction/evolution (ORR/OER) catalysts, enabling effective photocoupling to tune oxygen catalysis. The C4 N-enabled VLS-RZAB displays a low charge voltage of 1.35 V under visible light, which is below the theoretical RZAB voltage of 1.65 V, corresponding to a high energy efficiency of 97.78 %. Pairing a C4 N cathode with a polymer anode also endows an VLS-RPAB with light-boosted charge performance. It is revealed that the ORR and OER active sites in C4 N are separate carbon sites near pyrazine-nitrogen atoms and photogenerated energetic holes can activate OER for improved reaction kinetics.

Construction of Charring-Functional Polyheptanazine towards Improvements in Flame Retardants of Polyurethane.

Nitrogen-containing flame retardants have been extensively applied due to their low toxicity and smoke-suppression properties; however, their poor charring ability restricts their applications. Herein, a representative nitrogen-containing flame retardant, polyheptanazine, was investigated. Two novel, cost-effective phosphorus-doped polyheptazine (PCN) and cobalt-anchored PCN (Co@PCN) flame retardants were synthesized via a thermal condensation method. The X-ray photoelectron spectroscopy (XPS) results indicated effective doping of P into triazine. Then, flame-retardant particles were introduced into thermoplastic polyurethane (TPU) using a melt-blending approach. The introduction of 3 wt% PCN and Co@PCN could remarkably suppress peak heat release rate (pHRR) (48.5% and 40.0%), peak smoke production rate (pSPR) (25.5% and 21.8%), and increasing residues (10.18 wt%→17.04 wt% and 14.08 wt%). Improvements in charring stability and flame retardancy were ascribed to the formation of P-N bonds and P=N bonds in triazine rings, which promoted the retention of P in the condensed phase, which produced additional high-quality residues.

Autotaxin-LPA receptor axis in the pathogenesis of lung diseases.

Lysophosphatidic acid (LPA) is a small lipid which mediates a variety of cellular functions via the activation of LPA receptors. LPA is generated from lysophosphatidylcholine by the extracellular enzyme, autotaxin (ATX). Elevated ATX expression, LPA production and their signaling pathways have been reported in multiple pathological conditions of lung tissue, including inflammation, fibrosis and cancer. Emerging evidence has highlighted the importance of ATX and LPA receptors in the pathogenesis of lung diseases. Here, we briefly review the current knowledge of different roles of the ATX-LPA receptor axis in lung diseases focusing on inflammation, fibrosis and cancer.

[Intervention of glypican-3 genetic transcription on anti-proliferative effect of hepatoma cells with high metastatic potentiality].

OBJECTIVE: To explore the silencing glypican-3 (GPC-3) gene transcription by specific small hairpin RNA (shRNA) on the inhibition of hepatoma cells with high metastatic potentiality and hepatoma growth. METHODS: After MHCC-97H cells were transfected with higher effective GPC-3-shRNA, GPC-3 mRNA was analyzed by multiple FG-RT-PCR or protein by Western blot. Cell proliferation was detected by 5-ethynyl-2'-deoxyuridine and sulforhodamine B assay, its migratory metastasis and invasiveness by wound healing or transwell chamber system and cell apoptosis was detected by Caspase-Glo(®) 3/7 Luminescence assay. Nude mice were subcutaneously injected with stable MHCC-97H cells for observing the forming time or volume of xenograft tumors. And the expressions of GPC-3, ß-catenin, p-GSK3ß and CyclinD1 were analyzed by immunohistochemistry. RESULTS: After shRNA1 transfection with high efficiency (>80%), the expression of GPC-3 was down-regulated to 75.6% (t = 15.473, P < 0.001) at mRNA level in accordance with its protein, inhibiting cell proliferation (71.1%, t = 10.468, P < 0.001) notably, decreasing its migration (80.1%, t = 32.697, P < 0.001) and invasiveness (69.1%, t = 39.647, P < 0.001). ß-catenin was down-regulated (67.7%, t = 18.4, P < 0.001) and Gli1 increased (53.5%, t = -4.824, P = 0.008) with its protein. The average forming time of subcutaneous tumors was 11.2 days (d) in the shRNA group and it was significantly longer (P < 0.01) than that in the control (5.3 d) or shRNA-neg (5.5 d) group. And the average volume (65.5 mm(3)) of tumors with decreased GPC-3, ß-catenin, p-GSK3ß, and cyclinD1 expressions in the shRNA group was significantly smaller (P < 0.01) than that in the shRNA-neg (365.7 mm(3)) or control (404.8 mm(3)) group, respectively. CONCLUSION: Specific shRNA might intervene effectively the GPC-3 gene transcription and inhibit invasion and tumor growth. Thus GPC-3 may become a potential molecular target for hepatoma gene therapy.

[Short hairpin RNA mediated glypican-3 silencing inhibits hepatoma cell invasiveness and disrupts molecular pathways of angiogenesis].

OBJECTIVE: To construct glypican-3 (GPC-3) short hairpin RNA (shRNA) and investigate the effects of GPC-3 transcription silencing on hepatoma cell invasion and angiogenesis mechanisms. METHODS: GPC-3-specific shRNA and non-target control shRNA were constructed and transfected into the human hepatoma cell lines HepG2, MHCC-97H, and Huh7. shRNA-mediated silencing of GPC-3 expression was confirmed at the mRNA and protein levels by fluorescence quantitative reverse transcription (FQRT)-PCR and western blotting, respectively. The effect of silenced GPC-3 expression on cell proliferation was detected by EdU and sulforhodamine B assays, on migration by wound healing (scratch) assay, on invasion by transwell chamber assay, and on apoptosis by luminescence assay of caspase-3/7 activity. The effect of silenced GPC-3 expression on angiogenesis-related signaling factors was detected by FQRT-PCR (for the glioma-associated oncogene homolog-1 hedgehog signaling factor, GLI1, and the beta-catenin Wnt signaling factor, b-catenin), immunofluorescent staining (for the insulin-like growth factor-II, IGF-II), and ELISA (for the vascular endothelial growth factor, VEGF). Pairwise comparisons were made by the independent sample t-test, and multiple comparisons were made by one-way ANOVA. RESULTS: In all cell lines, transfection with the GPC-3-specific shRNA significantly reduced GPC-3 mRNA levels (% reduction as compared to the non-target control shRNA: HepG2, 89.2+/-6.0%, t = -25.753, P less than 0.001; MHCC-97H, 75.3+/-4.9%, t = -26.487, P less than 0.001; Huh7, 73.6+/-4.6%, t = -27.607, P less than 0.001); the GPC-3 protein levels were similarly reduced. The GPC-3 shRNA-silenced cells showed significantly reduced proliferative, migratory and invasive capacities, as well as significantly increased apoptosis. The shRNA-mediated GPC-3 silencing was accompanied by significant down-regulation of b-catenin mRNA (HepG2, 46.9+/-0.6%; MHCC-97H, 67.5+/-2.7%; Huh7, 56.3+/-8.4%) and significant up-regulation of GLI1 mRNA (HepG2, 49.2+/-28.6%; MHCC-97H, 54.6+/-24.4%; Huh7, 31.6+/-15.7%). At 72 h after transfection, the HepG2 cells showed significant down-regulation of VEGF protein (54.3+/-1.5%, t = 46.746, P less than 0.001). CONCLUSION: GPC-3 contributes to migration, invasion, angiogenesis, and apoptosis of hepatoma cells, possibly through its interactions with the Wnt/b-catenin and Hedgehog signaling pathways. GPC-3 may represent a useful target for gene silencing by molecular-based therapies to treat hepatocellular carcinoma.

Annexin A2 silencing inhibits invasion, migration, and tumorigenic potential of hepatoma cells.

AIM: To investigate the effects of Annexin A2 (ANXA2) silencing on invasion, migration, and tumorigenic potential of hepatoma cells. METHODS: Human hepatoma cell lines [HepG2, SMMC-7721, SMMC-7402, and MHCC97-H, a novel human hepatocellular carcinoma (HCC) cell line with high metastasis potential] and a normal hepatocyte cell line (LO2) were used in this study. The protein and mRNA expression levels of ANXA2 were analysed by western blotting and real-time polymerase chain reaction, respectively. The intracellular distribution profile of ANXA2 expression was determined by immunofluorescence and immunohistochemistry. Short hairpin RNA targeting ANXA2 was designed and stably transfected into MHCC97-H cells. Cells were cultured for in vitro analyses or subcutaneously injected as xenografts in mice for in vivo analyses. Effects of ANXA2 silencing on cell growth were assessed by cell counting kit-8 (CCK-8) assay (in vitro) and tumour-growth assay (in vivo), on cell cycling was assessed by flow cytometry and propidium iodide staining (in vitro), and on invasion and migration potential were assessed by transwell assay and wound-healing assay, respectively (both in vitro). RESULTS: The MHCC97-H cells, which are known to have high metastasis potential, showed the highest level of ANXA2 expression among the four HCC cell types examined; compared to the LO2 cells, the MHCC97-H expression level was 8-times higher. The ANXA2 expression was effectively inhibited (about 80%) by ANXA2-specific small hairpin RNA (shRNA). ANXA2 expression in the MHCC97-H cells was mainly localized to the cellular membrane and cytoplasm, and some localization was detected in the nucleus. Moreover, the proliferation of MHCC97-H cells was obviously suppressed by shRNA-mediated ANXA2 silencing in vitro, and the tumour growth inhibition rate was 38.24% in vivo. The percentage of MHCC97-H cells in S phase dramatically decreased (to 27.76%) under ANXA2-silenced conditions. Furthermore, ANXA2-silenced MHCC97-H cells showed lower invasiveness (percentage of invading cells decreased to 52.16%) and suppressed migratory capacity (migration distance decreased to 63.49%). It is also worth noting that shRNA-mediated silencing of ANXA2 in the MHCC97-H cells led to abnormal apoptosis. CONCLUSION: shRNA-mediated silencing of ANXA2 suppresses the invasion, migration, and tumorigenic potential of hepatoma cells, and may represent a useful target of future molecular therapies.