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This study comprehensively examines the influence of phenol-formaldehyde resin (PF) on the performance of base asphalt and its mixtures for road applications, emphasizing its innovative use in enhancing pavement quality. Optimal PF content was determined through the evaluation of standard indicators and rotational viscosity. In-depth analyses of PF-modified asphalt's high- and low-temperature rheological properties and viscoelastic behavior were conducted using dynamic shear rheometers and bending beam rheometers. Aging resistance was assessed through short-term aging and performance grade (PG) grading. Moreover, Marshall and water stability tests were performed on PF-modified asphalt mixtures. Findings indicate that the uniform dispersion of PF particles effectively inhibits asphalt flow at high temperatures, impedes oxygen penetration, and delays the transition from elasticity to viscosity. These unique properties enhance the high-temperature stability, rutting resistance, and aging resistance of PF-modified asphalt. However, under extremely low temperatures, PF's brittleness may impact asphalt flexibility. Nonetheless, the structural advantages of PF-modified asphalt, such as improved mixture density and stability, contribute to enhanced high-temperature performance, water stability, adhesion, and freeze-thaw cycle stability. This research demonstrates the feasibility and effectiveness of using PF to enhance the overall performance of base asphalt and asphalt mixtures for road construction.
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Silk-based triboelectric nanogenerators (TENGs) have been demonstrated as an ideal platform for self-powered systems. The source of silk, Bombyx mori, entails a valuable ingredient, sericin (SS), viewed as a binder in composites. Interestingly, SS is rich in the amorphous region, possibly resulting in triboelectrification enhancement between the amorphous region and the crystallization region when subject to external pressure. However, most researchers remove the SS component when designing silk-TENGs to eliminate immunological responses as implantation in vivo through complicated degumming, rehydration, and dialysis procedures. Herein, integral SS retention was utilized to fabricate silk-TENGs without affecting the output performance. We designed, for the first time, an ultra-robust and natural silkworm cocoon layer (SCL)/polydimethylsiloxane (PDMS)-TENG as an energy harvester to scavenge waste energy from human motions. The working mechanisms and influence of operational parameters are explored and studied. Working in the contact-separation mode, the electrical outputs of the SCL/PDMS-TENG in terms of open-circuit voltage, short-circuit current, and power density reaches 126 V, 3 µA, and 216 mW/m2, respectively. The integrated self-charging TENG is demonstrated to power small electronic electronics and monitor human motions. This work widens a new dielectric material selection with SS retention to boost the output performance of TENGs for practical applications.
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@#[Abstract] Objective: To construct a circRNA profile of esophageal squamous cell carcinoma (ESCC) and analyze differentially expressed circRNAs. Methods: Samples were taken from 3 patients with esophageal squamous cell carcinoma who were hospitalized in the Department of Thoracic Surgery, Jintan Hospital, Jiangsu University from June 2018 to February 2019. The circRNA expression profile was constructed by high-throughput sequencing technique, and the circRNA differentially expressed in 3 pairs of esophageal squamous cell carcinoma tissues and adjacent tissues was detected. The biological functions and related signal pathways of these circRNA were analyzed by GO and KEGG techniques. Results: By comparing the expression levels of circRNA between esophageal squamous cell carcinoma and adjacent tissues, 905 differentially expressed circRNA were found, of which 404 were up-regulated and 501 were down-regulated. hsa_circ_0004390 was the CIRC RNA with the highest up-regulation factor (FC=7.9712), and novel_circ_0012687 was the one with the highest down-regulation factor. GO and KEGG analysis showed that these circRNA may be involved in biological processes such as cell cycle, cell components and protein binding of cancer cells, and signal pathways such as Hippo and cGMP-PKG. Conclusion: The expression profile analysis of circRNA in esophageal squamous cell carcinoma showed that the significantly differentially expressed circRNA could be used as a potential biomarker of esophageal squamous cell carcinoma.
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In this contribution, citrate-based fluorophore (CF)-modified cellulose nanocrystals (CNCs) were prepared in a facile manner using sulfuric acid hydrolysis of citric acid/cysteine-treated microcrystalline celluloses. These rod-like CNCs have an average length of 156 nm and an average width of 7.9 nm. Because of conjugated CFs, these CNCs exhibit typical fluorescence characteristics, including a maximum excitation wavelength at 350 nm, maximum emission wavelength at 435 nm, high quantum yield of 83%, and good photostability. More importantly, these fluorescent CNCs exhibit a selective quenching effect toward Fe3+ ions; meanwhile, these CNCs exhibit negligible cytotoxicity and were internalized by cells. Therefore, these CNCs can be used as a fluorescence probe for detecting Fe3+ ions in living cells.
