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Considering the molar mass between entanglements to be an intrinsic property of ultra-high molecular weight polyethylene (UHMWPE), the number of entanglements per chain increases with the increasing molar mass, correspondingly,...

Background Perineural invasion (PNI) is associated with metastasis in malignancies, including intrahepatic cholangiocarcinoma (ICC), and is correlated with poor prognosis. Methods The study included three large cohorts: ZS-ICC and TMA cohorts from our team, MSK cohort from a public database, and a small cohort named cohort 4. Prognostic implications of PNI were investigated in MSK cohort and TMA cohort. PNI-related genomic and transcriptomic profiles were analyzed in MSK and ZS-ICC cohorts. GO, KEGG, and ssGSEA analyses were performed. Immunohistochemistry was used to investigate the relationship between PNI and markers of neurons, hydrolases, and immune cells. The efficacy of adjuvant therapy in ICC patients with PNI was also assessed. Results A total of 30.6% and 20.7% ICC patients had PNI in MSK and TMA cohorts respectively. Patients with PNI presented with malignant phenotypes such as high CA19-9, the large bile duct type, lymph node invasion, and shortened overall survival (OS) and relapse-free survival (RFS). Nerves involved in PNI positively express tyrosine hydroxylase (TH), a marker of sympathetic nerves. Patients with PNI showed high mutation frequency of KRAS and an immune suppressive metastasis prone niche of decreased NK cell, increased neutrophil, and elevated PD-L1, CD80, and CD86 expression. Patients with PNI had an extended OS after adjuvant therapy with TEGIO, GEMOX, or capecitabine. Conclusion Our study deciphered the genomic features and the immune suppressive metastasis-prone niche in ICC with PNI. Patients with PNI showed a poor prognosis after surgery but a good response to adjuvant chemotherapy. Graphical abstract

We analyzed the spatial distribution pattern and correlation of the top four dominant tree species in a 2 hm以黔中天龙山2 hm

In planetary science, it is an important basic work to recognize and classify the features of topography and geomorphology from the massive data of planetary remote sensing. Therefore, this article proposes a lightweight model based on VGG-16, which can selectively extract some features of remote sensing images, remove redundant information, and recognize and classify remote sensing images. This model not only ensures the accuracy, but also reduces the parameters of the model. According to our experimental results, our model has a great improvement in remote sensing image classification, from the original accuracy of 85%–98% now. At the same time, the model has a great improvement in convergence speed and classification performance. By inputting the remote sensing image data of ultra-low pixels (64 * 64) into our model, we prove that our model still has a high accuracy rate of 95% for the remote sensing image with ultra-low pixels and less feature points. Therefore, the model has a good application prospect in remote sensing image fine classification, very low pixel, and less image classification.

In this work, through the coordination of C3 symmetric azopyridine ligands and Ag(i), coordination polymers with azo groups on the main chain were prepared. The trans coordination polymer formed an organogel with a network of nanofibers at low critical gelation concentrations, and it exhibited the abilities of self-healing and multi-stimuli response to heating, light, mechanical shearing, and chemicals due to the presence of dynamic coordinating bonds. On the other hand, the cis coordination polymer was found to assemble into nanoparticles to give a responsive colloid, which can produce fibrous precipitation in several days upon visible light irradiation due to the isomerization of the azo groups. This work provides a novel example for the design of a multi-responsive organogel and colloid based on the structural transformation of coordination polymers.

Isodimorphism and isomorphism are becoming mature approaches but separately used to regulate crystallization behavior of random copolymers and thus their performances. Most of the research work is ...

The wear tests of titanium matrix composites (TMCs) at the loads of 50, 100, 120, and 150 N were carried out with an MMW-1 vertical universal friction and wear tester to study the addition of multilayer graphene (MLG)/nano-Fe2O3 composites (0, 0.1, 0.2, 0.3, 0.4, and 0.5 g) on the dry sliding wear behavior of TMCs. TMCs presented a marked variation in wear loss as a function of the amount of MLG/Fe2O3 addition, and a significant decrease in the friction coefficient was obtained, reducing this parameter up to 50%. With the rise and fall of wear loss, TMCs underwent a transition from severe wear to mild wear. These phenomena were attributed to the existence of a protective lubricating film, which prevented the surface from coming in direct contact, and the lubricating film was 15–20 μm thick and made up of MLG/Fe2O3 (1:2) nanocomposites. Its structure was speculated to be similar to a rolling wood.

Background Forkhead box protein A1 (FOXA1), acting as a transcriptional activator for liver-specific transcripts, plays a vital part in proliferation, apoptosis and cell cycle. Methods The mRNA expression of FOXA1 in 90 HCC tissues and matched adjacent non-tumor tissues was determined by qRT-PCR. The downstream and upstream regulators of FOXA1 were identified by bioinformatics analysis and experimental confirmation. Results We found out that the expression of FOXA1 was obviously higher in hepatocellular carcinoma (HCC) tissues than that in matched non-tumor tissues. Similarly, FOXA1 is also highly expressed in HCC cell lines as compared with normal human hepatic cell line L02. Clinical association analysis indicated that high expression of FOXA1 was prominently correlated with high HBV level, large tumor size, high venous infiltration, high Edmondson-Steiner grading, and advanced tumor-node-metastasis tumor stage. Furthermore, the in vitro tests showed that ectopic expression of FOXA1 promoted HepG2 cell proliferation and suppressed apoptosis. In contrast, the downregulation of FOXA1 inhibited cell proliferation, and induced apoptosis in Hep3B cells. To investigate the functional mechanism of FOXA1, anterior gradient 2 (AGR2), an executor in proliferation and apoptosis, was identified as the direct target gene of FOXA1. Meanwhile, we also found the expression of FOXA1 could be inhibited by miR-212-3p, which working as a tumor suppressor downregulated in HCC. Conclusion We revealed that FOXA1 exerted its biological function by regulating AGR2 expression, and its ectopic expression may be blamed for low expression of miR-212-3p.

Background Necroptosis is a necrotic programmed cell death with potent immunogenicity. Due to the dual effects of necroptosis on tumor growth, metastasis and immunosuppression, we evaluated the prognostic value of necroptosis-related genes (NRGs) in hepatocellular carcinoma (HCC). Methods We first analyzed RNA sequencing and clinical HCC patient data obtained to develop an NRG prognostic signature based on the TCGA dataset. Differentially expressed NRGs were further evaluated by GO and KEGG pathway analyses. Next, we conducted univariate and multivariate Cox regression analyses to build a prognostic model. We also used the dataset obtained from the International Cancer Genome Consortium (ICGC) database to verify the signature. The Tumor Immune Dysfunction and Exclusion (TIDE) algorithm was used to investigate the immunotherapy response. Furthermore, we investigated the relationship between the prediction signature and chemotherapy treatment response in HCC. Results We first identified 36 differentially expressed genes out of 159 NRGs in hepatocellular carcinoma. Enrichment analysis showed that they were mainly enriched in the necroptosis pathway. Four NRGs were screened by Cox regression analysis to establish a prognostic model. The survival analysis revealed that the overall survival of patients with high-risk scores was significantly shorter than that of patients with low-risk scores. The nomogram demonstrated satisfactory discrimination and calibration. The calibration curves validated a fine concordance between the nomogram prediction and actual observation. The efficacy of the necroptosis-related signature was also validated by an independent dataset and immunohistochemistry experiments. TIDE analysis revealed that patients in the high-risk group were possibly more susceptible to immunotherapy. Furthermore, high-risk patients were found to be more sensitive to conventional chemotherapeutic medicines such as bleomycin, bortezomib, and imatinib. Conclusion We identified 4 necroptosis-related genes and established a prognostic risk model that could potentially predict prognosis and response to chemotherapy and immunotherapy in HCC patients in the future.

Charles Mauguin, in his groundbreaking 1911 paper on mechanically twisted, nematic liquid crystal cells, speculated on the possibility of measuring the effects on polarized transmitted light along a sufficiently plastic crystalline material with a preserved twist. This experiment is realized in crystalline, spherulitic polymers wherein twisted, fibrous lamellae emanating from the cores are directed along the wave vector of the incident light. Twisted lamellae of synthetic polymers are found in optically banded spherulites of both chiral and achiral polymers. The material’s chirality (the mesoscopic twist sense) is established at the cores where crystals nucleate. However, determining the twist sense directly by microstructural analyses (e.g., scanning probe or electron microscopy) is possible only in favorable cases. An optical assay, of the kind suggested by Mauguin, would be universal. The differential transmission of circularly polarized light in the cores of polymer spherulites was imaged by complete ...

In recent years, Al-5Mg alloy thermal spray coatings have been used as an anti-corrosion coating applied for various components of steel structures, in some cases it was covered by the conventional heavy-duty coating. However, the deterioration characteristics of overlapping layers between thermal spray layer and heavy-duty paint coating still not clear. In this study, to compare the anti-corrosion characteristics of the single thermal spray coating and overlapping layers, the accelerated cyclic exposure tests were carried out on specimens with three types of coating layers. To clarify the deterioration characteristics, the cross-cut defect were introduced into specimens, and the EIS measurements, glossiness test, EPMA elemental analyses were conducted on test specimens. The test results indicated that the deterioration of the overlapping layer at the steel base-exposed portion occurs earlier than the case of Al-5Mg thermal spray coating. In addition, the deterioration of thermal spray coating was accelerated by the sealing treatment in specimen with overlapping layers.

Reducing the risk of contamination with foodborne pathogens is paramount in maintaining safety of produce. The raspberry industry uses chlorine spray as a control measure before conveying ...

Metal-organic gels showing potential application in catalysis have received much concern. In this work, we designed and synthesized two metal-organic gels based on coordination between FeIII and pyridine ligands at room temperature. The gels were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) to reveal their assembly structures and morphologies, and it was found the metal-organic gel derived from di-topic ligand was composed of three-dimensional network of nanofibers, while the gel derived from tri-topic ligand was constituted of sponge-like structure with amorphous phase. Rheological analysis showed the gel consisting of nanofiber networks displayed self-healing property. The gels were used as catalysts for selective ethylene dimerization, and the optimum catalysis results of the gel with nanofibers reached the maximal catalytic activity of 1.48×105 g/(mol Fe⋅h) with C4 yield more than 90 %, whereas the sponge-like gel only gave 38 % C4 products at the same condition. The higher dimerization selectivity of the former FeIII gel was attributed to its regular assembly structure and lower steric hindrance of the surface metal sites. Due to its catalytic activity, high selectivity and preparation simplicity, the FeIII gel might be potentially applicable for the preparation of C4 α-olefins.

Biodegradable poly(1,4-butylene adipate) (PBA) has been highlighted of distinct polymorphism and receives extensive research by adding nucleating agents. Usually, only a single nucleating mechanism...

The rigid Troger's base microporous polymers were utilized to fabricate mixed matrix membranes with NH2-MIL-53 (Al) nanocrystals. Such N containing polymers have the ability to interact with NH2-MIL-53 (Al), therefore yielding transparent, robust, and plasticization–resistant hybrid membranes. The resulting membranes show a remarkable increase in gas permeability up to 3 times as a result of improved gas diffusivity and solubility without the selectivity loss. Much more improvements in CO2 solubility arise from the presence of CO2-adsorbing sites in Troger's base polymers and the CO2-selective adsorption properties of NH2-MIL-53 (Al), correspondingly leading to increased CO2 solubility selectivity. The gas separation performance shifts toward Robeson upper bonds upon the addition of MOFs. Particularly, the H2/CH4 separation performance overcomes the 2008 Robeson upper bond. In mixed gas feeds, the membranes display CO2 gas permeability up to 308 Barrer and CO2/N2 and CO2/CH4 mixed gas selectivities of 25.4 and 23.6 with virtually no evidence of plasticization. Much higher mixed-gas selectivity than permselectivity in these membranes are strongly correlated with the strongly adsorbing CO2 gas molecules blocking transport of large size molecules.

While polymer extended-chain crystals (ECCs) own promising physicochemical properties, effective product and application of ECCs is still challenging. Here, we develop an industrializable and sustainable production procedure process for ECCs of poly(butylene succinate) (PBS), which consists of a specially-designed melt mixing of the polymer and urea in internal mixer to produce inclusion complex and thereafter a washing step with water. The prepared ECCs show melting point at 137 °C and crystallinity higher than 90%, and the auxiliary materials, urea and water, can be recycled. The ECCs are further used as highly effective nucleating agent and reinforcer for commercial PBS, resulting in remarkable simultaneous increases in crystallization temperature, yield stress and elongation at break due to the perfect lattice matching and interfacial compatibility. Moreover, a shape memory material of single component of PBS has been fabricated with the in-situ addition of ECCs.

Sliding wear tests of a titanium-matrix composite (TMC) against M35 steel were performed at room temperature. To improve the wear performance of the TMC, an attempt was made to induce a protective tribofilm by artificially supplying nanoscale materials, viz. multilayer graphene (MLG), Fe2O3, and their composite and mixture, onto the sliding tracks. Irrespective of the load, MLG or Fe2O3 additives could hardly improve the wear performance of the TMC because of a lack of load-bearing or lubricant capacity. However, the MLG/Fe2O3 nanocomposite and MLG + Fe2O3 mechanical mixture could effectively improve the wear performance. Interestingly, a critical load existed, at or below which extremely low wear loss and friction coefficient were obtained, which can be attributed to the formation of a protective tribofilm.

Big spherulite structure and high crystallinity are the two main drawbacks of poly(butylene succinate) (PBS) and hinder its application. In this work, a new type of copolyester poly(butylene succinate-co-butylene acetylenedicarboxylate) (PBSAD) is synthesized. With the incorporation of acetylenedicarboxylate (AD) units into PBS chains, the crystallization temperature and crystallinity are depressed by excluding AD units to the amorphous region. In contrast, the primary nucleation capability is significantly strengthened, without changing the crystal modification or crystallization kinetics, leading to the recovery of total crystallization rate of PBSAD under the same supercooling condition. The existence of specific interaction among AD units is found to be crucial. Although it is too weak to contribute to the melt memory effect at elevated temperature, the interaction continuously strengthens as the temperature falls down, and the heterogeneous aggregation of AD units keeps growing. When the aggregating process reaches a certain extent, it will induce the formation of a significant amount of crystal nuclei. The unveiled nucleation mechanism helps to design PBS copolymer with good performance.

Big spherulite structure and high crystallinity are the two main drawbacks of poly(butylene succinate) (PBS) and hinder its application. In this work, a new type of copolyester poly(butylene succinate-co-butylene acetylenedicarboxylate) (PBSAD) is synthesized. With the incorporation of acetylenedicarboxylate (AD) units into PBS chains, the crystallization temperature and crystallinity are depressed by excluding AD units to the amorphous region. In contrast, the primary nucleation capability is significantly strengthened, without changing the crystal modification or crystallization kinetics, leading to the recovery of total crystallization rate of PBSAD under the same supercooling condition. The existence of specific interaction among AD units is found to be crucial. Although it is too weak to contribute to the melt memory effect at elevated temperature, the interaction continuously strengthens as the temperature falls down, and the heterogeneous aggregation of AD units keeps growing. When the aggregating process reaches a certain extent, it will induce the formation of a significant amount of crystal nuclei. The unveiled nucleation mechanism helps to design PBS copolymer with good performance.

The crystallization and melting behavior of polymers is of theoretical importance. In this work, poly(butylene succinate) (PBS) was selected as an example to study such behavior at low supercooling via introduction of the extended-chain crystal (ECC) of the same polymer as nucleating agent. The crystallization of PBS with its ECC as nucleating agent in a wide temperature range (90–127 °C) and the following melting behavior were studied. It is revealed that the melting point (Tm, for Tc≥113 °C) and the annealing peak temperature (Ta, for Tc=90–100 °C) show similar asymptotic behavior. Both Tm and Ta approach to a value of ca. 3.3 °C higher than the corresponding Tc when the crystallization time tc approaches the starting point. That is to say, the Hoffman-Weeks plot is parallel to Tm=Tc line. The crystallization line became parallel to the melting line when PBS was crystallized at Tc higher than 102 °C. Based on these results, we propose that the parallel relationship and the intrinsic similarity between the Ta and the Tm observed at the two ends of the Tc range could be attributed to the metastable crystals formed at the beginning of crystallization.

In a previous study, the authors have developed a ground corrosion sensor to evaluate the corrosivity of steel members near the ground. This research aimed at the fundamental investigation of the output properties and practicality of a ground corrosion sensor. The output characteristics were verified by two electrochemical tests. The corrosion rates were evaluated using sensor measurements and indoor exposure tests by simulating NaCl aqueous solution environments, which contain air-liquid interfaces. Besides, the actual corrosion depths obtained from the exposure tests were compared with those estimated by the sensor. Moreover, an evaluation method for time-dependent corrosion depth prediction of steel members using the corrosion sensor was proposed.

Uracil was investigated as a nucleating agent for bacterially synthesized copolymer of R-3-hydroxybutyrate and 4-hydroxybutyrate (P3HB4HB). The effects of uracil on the crystallization kinetics, melting behavior, spherulite morphology, crystalline structure and rheological behavior of P3HB4HB were investigated by differential scanning calorimetry (DSC), polarized optical microscopy (POM), wide angle X-ray diffraction (WAXD), Fourier transform infrared (FTIR) spectroscopy and rheometer. The crystallization half-times (t1/2) of P3HB4HB decreased significantly in the presence of uracil. With addition of 1 wt% uracil, the t1/2 value of P3HB4HB melt crystallizing at 95 °C decreased to 2.37 min, about 3.5% of the neat polymer. In-situ FTIR spectra revealed the clear interactions between uracil and P3HB4HB in composites, inducing some precursory structures. Furthermore, the storage and loss modulus of nucleated P3HB4HB increased exponentially compared with neat P3HB4HB. It was proposed that uracil is an environment friendly nucleating agent and rheological modifier for the P3HB4HB.

We successfully use a co-precipitation method to prepare inclusion complex between poly(butylene adipate) (PBA) chains (guest component) and urea molecules (host component). The PBA/urea inclusion complex is confirmed to adopt a hexagonal crystal modification with lattice parameters of a = 8.14 A and c = 10.92 A, and the interaction between PBA chains and urea is van der Waals force. The singly isolated PBA chains are suggested to take some gauche conformation, which is different from the all-trans conformation in β-form PBA. Furthermore, we employ the isolated PBA chains which are uniformly pre-established in a specific conformation in urea channels to regulate the crystal form of PBA for the first time. After removing the host urea molecules, the coalesced PBA chains are found to solely crystallize into α-form crystals at different coalescing temperatures. By comparing the FTIR spectra, it is found that PBA chains in inclusion complex plausibly contain some similar conformers as those in α-form crystal, which is suggested to be the intrinsic reason for the sole formation of α-form crystals. This research proves that inclusion complex can be used as a very effective method to regulate polymorphism of semi-crystalline polymers.