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Gelatin (G) is a commonly used natural biomaterial owing to its good biocompatibility and easy availability. However, using pure gelatin as a bioink can barely achieve an ideal shape fidelity in 3D printing. In this study, Antheraea pernyi silk fibroin nanofibers (ASFNFs) with arginine-glycine-aspartic acid (RGD) peptide and partial natural silk structure are extracted and combined with pure gelatin bioink to simultaneously improve the shape fidelity and cytocompatibility of corresponding 3D printed scaffold. Results show that the optimum printing temperature is 30 °C for these bioinks. The printed filaments using 16G/4ASFNFs bioink (16wt% gelatin and 4wt% ASFNFs) demonstrate better morphology and larger pore size than those printed by pure gelatin bioink (20G, 20wt% gelatin), thus successfully improve the shape fidelity and porosity of the 3D printed scaffold. The 16G/4ASFNFs scaffold also demonstrate higher swelling ratio and faster degradation rate than the pure gelatin scaffold. Moreover, the cell viability and proliferation ability of Schwann cells cultured on the 16G/4ASFNFs scaffold are significantly superior than those cultured on the pure 20G scaffold. The ASFNFs enhanced 16G/4ASFNFs scaffold reported here are expected to be a candidate with excellent potential for biomedical applications.

The main limitation of plastic stents is the relatively short stent patency due to occlusion. We designed enteral extended biliary stents with lengths of 26 cm (EEBS-26 cm) and 30 cm (EEBS-30 cm) to prolong stent patency. This study aimed to compare patency among EEBS-26 cm, EEBS-30 cm, and conventional plastic biliary stent (CPBS).A single-center prospective randomized controlled study was conducted. Eligible patients were randomized into the EEBS-26 cm, EEBS-30 cm, and CPBS groups, respectively. All patients were followed up every 3 months until stent occlusion, patient death, or at 12-month follow-up. The primary outcome was stent patency. The secondary outcomes included stent occlusion rate, patient survival, mortality, the rate of technical success, and adverse events.Totally 117 patients were randomized into the three groups. There were no significant differences among the three groups in technical success rate, hospital stay, mortality, patient survival, and adverse events (P = 1.000, 0.553, 0.965, 0.302, and 0.427, respectively). Median stent patency durations in the EEBS-26 cm, EEBS-30 cm, and CPBS groups were 156.0 (95% CI 81.6-230.4) days, 81.0 (95% CI 67.9-94.1) days, and 68.0 (95% CI 20.0-116.0) days, respectively (P = 0.002). The EEBS-26 cm group had longer stent patency compared with the CPBS (P = 0.007) and EEBS-30 cm (P 0.001) groups. The EEBS-26 cm group had lower stent occlusion rates compared with the other groups at 6 months (48.1% vs. 90.5% vs. 82.8%, P = 0.001) and 9 months (75.0% vs. 100.0% vs. 92.9%, P = 0.022).EEBS-26 cm has prolonged stent patency and is safe and effective for the alleviation of unresectable extrahepatic malignant biliary obstruction.

Neural interface is a powerful tool to control the varying neuron activities in the brain, where the performance can directly affect the quality of recording neural signals and the reliability of

Due to the innate extracellular matrix mimicking features, fibrous materials exhibited great application potential in biomedicine. In developing excellent fibrous biomaterial, it is essential to reveal the corresponding inherent fiber features’ effects on cell behaviors. Due to the inevitable ‘interference’ cell adhesions to the background or between adjacent fibers, it is difficult to precisely reveal the inherent fiber diameter effect on cell behaviors by using a traditional fiber mat. A single-layer and parallel-arranged polycaprolactone fiber pattern platform with an excellent non-fouling background is designed and constructed herein. In this unique material platform, the ‘interference’ cell adhesions through interspace between fibers to the environment could be effectively ruled out by the non-fouling background. The ‘interference’ cell adhesions between adjacent fibers could also be excluded from the sparsely arranged (SA) fiber patterns. The influence of fiber diameter on stem cell behaviors is precisely and comprehensively investigated based on eliminating the undesired ‘interference’ cell adhesions in a controllable way. On the SA fiber patterns, small diameter fiber (SA-D1, D1 means 1 μm in diameter) may seriously restrict cell proliferation and osteogenesis when compared to the middle (SA-D8) and large (SA-D56) ones and SA-D8 shows the optimal osteogenesis enhancement effect. At the same time, the cells present similar proliferation ability and even the highest osteogenic ability on the densely arranged (DA) fiber patterns with small diameter fiber (DA-D1) when compared to the middle (DA-D8) and large (DA-D56) ones. The ‘interference’ cell adhesion between adjacent fibers under dense fiber arrangement may be the main reason for inducing these different cell behavior trends along with fiber diameters. Related results and comparisons have illustrated the effects of fiber diameter on stem cell behaviors more precisely and objectively, thus providing valuable reference and guidance for developing effective fibrous biomaterials.

Silk fibroin (SF)-based electroactive biomaterials with favorable electroconductive property and transparency have great potential applications for cell culture and tissue engineering. Poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) is an excellent candidate as a conductive component, which has been widely used in the field of bioelectronics; however, it is hard to be directly coated onto the surface of regenerated SF (RSF) materials with good stability under a cell culture environment. In this study, a one-step facile PEDOT:PSS modification approach for RSF films based on a suitable post-treatment process of RSF was developed. PEDOT:PSS was successfully embedded and fixed into the shallow surface of an RSF film, forming a tightly conjunct conductive layer on the film surface based on the conformation transition of RSF during the post-treatment process. The conductive layer demonstrated a PSS-rich surface and a PEDOT-rich bulk structure and showed excellent stability under a cell culture environment. More specifically, the robust RSF/PEDOT:PSS film achieved in the post-treatment formula with 70% ethanol proportion possessed best comprehensive properties such as a sheet resistance of 3.833 × 10

Nowadays, numerous studies have focused on the newly developed technologies for the thorough removal of tetracyclines (TCs). The efficient removal of trace-amount pollutants requires the development of improved materials with higher adsorption capacity and increased adsorption selectivity. Zn(II)-mediated chitosan nonwoven fabric (Zn-CSNW) adsorbent with coordination capability was explored for the effective and selective removal of TC. The adsorption of TC to Zn-CSNW could reach equilibrium in about 30 min with a maximum adsorption capacity of 195.9 mg/g. It exhibited high anti-interference performance for TC adsorption at low concentrations, with good regeneration and effective reuse. Except for citrate, organic materials similar in structure to TC or common ions in aqueous solutions did not show obvious competition for the adsorption of low concentrations of TC. Additionally, the inherent fluorescence of chitosan and the fluorescence sensitization effect of Zn2+ for TC enabled function of Zn-CSNW as an indicator of the adsorption of TC by changes in fluorescence color and intensity under UV light (365 nm). It can indicate the saturation state of the Zn-CSNW, which will bring convenience to the use of the adsorbent. The Zn(II)-mediated coordination interaction plays a vital role in both the selective recognition of TC and the fluorescence sensing of adsorption amount, demonstrating an affordable and effective strategy for the treatment of water containing low amounts of antibiotics.

SARS-CoV-2 has high infectivity and some of its variants have higher transmissibility. To explore the high infectivity mechanism, the charge distributions of SARS-CoV, SARS-CoV-2, and variants of concern were calculated through a series of net charge calculation formulas. The results showed that the SARS-CoV-2 spike protein had more positive charges than that of SARS-CoV. Further results showed that the variants had similar but higher positive charges than preexisting SARS-CoV-2. In particular, the Delta variant had the greatest increase in positive charges in S1 resulting in the highest infectivity. In particular, the S1 positive charge increased greatly in the Delta variant. The S1 positive charge increased, and due to the large negative charge of angiotensin-converting enzyme-2 (ACE2), this resulted in a large increase in Coulomb’s force between S1 and ACE2. This finding agrees with the expectation that the positive charges in the spike protein result in more negative charges on SARS-CoV-2 antibodies than that of SARS-CoV. Thus, the infectivity of a novel SARS-CoV-2 variant may be evaluated preliminarily by calculating the charge distribution.

Objective We sought to determine the biocompatibility of electrospun regenerated silk fibroin (RSF) mats with inner ear progenitors, especially their effect on the differentiation of inner ear progenitors into hair cells. Methods Neonatal mouse cochleae (n = 20) were collected and digested and allowed to form spheres over several days. Cells digested from the spheres were then seeded onto aligned or random RSF mats, with laminin-coated coverslips serving as controls. The inner ear progenitor cell mortality was examined by TUNEL labeling, and the adhesion of cells to the RSF mats or coverslip was determined by scanning electron microscopy. Finally, the number of hair cells that differentiated from inner ear progenitors was determined by Myosin7a expression. Unpaired Student’s t-tests and one-way ANOVA followed by a Dunnett’s multiple comparisons test were used in this study ( p < 0.05). Results After 5 days of culture, the inner ear progenitors had good adhesion to both the aligned and random RSF mats and there was no significant difference in TUNEL+ cells between the mats compared to the coverslip ( p > 0.05). After 7 days of in vitro differentiation culture, the percentage of differentiated hair cells on the control, aligned, and random RSF mats was 2.5 ± 0.5%, 2.7 ± 0.4%, and 2.4 ± 0.2%, respectively, and there was no significant difference between Myosin7a+ cells on either RSF mat compared to controls ( p > 0.05). Conclusion The aligned and random RSF mats had excellent biocompatibility with inner ear progenitors and helped the inner ear progenitors maintain their stemness. Our results thus indicate that RSF mats represent a useful scaffold for the development of new strategies for inner ear tissue engineering research.

Bremsstrahlung $\gamma$ production in heavy ion reactions at Fermi energies carries important physical information including the nuclear symmetry energy at supra-saturation densities. In order to detect the high energy Bremsstrahlung $\gamma$ rays, a hodoscope consisting of 15 CsI(Tl) crystal read out by photo multiplier tubes has been built, tested and operated in experiment. The resolution, efficiency and linear response of the units to $\gamma$ rays have been studied using radioactive source and $({\rm p},\gamma)$ reactions. The inherent energy resolution of $1.6\%+2\%/E_{\gamma}^{1/2}$ is obtained. Reconstruction method has been established through Geant 4 simulations, reproducing the experimental results where comparison can be made. Using the reconstruction method developed, the whole efficiency of the hodoscope is about $2.6\times 10^{-4}$ against the $4\pi$ emissions at the target position, exhibiting insignificant dependence on the energy of incident $\gamma$ rays above 20 MeV. The hodoscope is operated in the experiment of $^{86}$Kr + $^{124}$Sn at 25 MeV/u, and a full $\gamma$ energy spectrum up to 80 MeV has been obtained., Comment: 9 pages, 19 figures

Aconitum carmichaelii Debx. is famous for the bioactive aconitum alkaloids as traditional Chinese medicine. Endophytic bacteria play vital roles in plant growth, health, and the production of secondary metabolites such as alkaloids. In this study, we employed 16 S rRNA amplicon high-throughput sequencing to determine the root endophytic bacterial community of A. carmichaelii Debx. collected from three main producing areas including the geo-authentic area in China, high performance liquid chromatography to measure the contents of six bioactive alkaloids and correlation analysis to explore the relationship among environmental factors, alkaloids contents, and endophytic bacterial community. The results indicated that the root core microbiota of A. carmichaelii Debx. was dominated by Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria. Root endophytic bacterial community in the geo-authentic area was distinct from the other two regions. Soil nitrogen contents, organic matter, and temperature were the main factors contributing to the endophytic bacterial community structure. Significant correlation was found between alkaloids contents and some bacterial genera. Particularly, the abundance of Lactobacillus was positively correlated with the contents of benzoyl-mesaconitine and benzoyl-aconine. This study provided the first insight into the root endophytic bacterial community composition of A. carmichaelii Debx., and can direct further isolation of functional bacterial strains.

Biomemristors have attracted significant attention because of their potential applications in logic operations, nonvolatile memory, and synaptic emulators, thus leading to the urgent need to improve memristive performance. In this work, a silk fibroin (SF)-based memristor, integrated with both low power and low operating current simultaneously, has been reported. Doping the SF with Ag and an ethanol-based post-treatment promote microcrystal formation in the bulk of the SF. This induces carrier transport along fixed, short paths and results in a low set voltage, low operating current, and high memristive stability. Such performances can greatly reduce power consumption and heat generation, beneficial for the accuracy and durability of memristor devices. The memristive mechanism of SF-based memristors with different Ag contents is the space-charge-limited conduction (SCLC) mechanism. In addition, the nonlinear transmission property of SF-based memristors suggests useful applications in bioelectronics.

Silk fibroin (SF) is a promising biomaterial due to its good biocompatibility, easy availability, and high mechanical properties. Compared with mulberry silk fibroin (MSF), nonmulberry silk fibroin (NSF) isolated from typical nonmulberry silkworm silk exhibits unique arginine-glycine-aspartic acid (RGD) sequences with favorable cell adhesion enhancing effect. This inherent property probably makes the NSF more suitable for cell culture and tissue regeneration-related applications. Accordingly, various types of NSF-based biomaterials, such as particles, films, fiber mats, and 3D scaffolds, are constructed and their application potential in different biomedical fields is extensively investigated. Based on these promising NSF biomaterials, this review firstly makes a systematical comparison between the molecular structure and properties of MSF and typical NSF and highlights the unique properties of NSF. In addition, we summarize the effective fabrication strategies from degummed nonmulberry silk fibers to regenerated NSF-based biomaterials with controllable formats and their recent application progresses in cell behavior regulation and tissue regeneration. Finally, current challenges and future perspectives for the fabrication and application of NSF-based biomaterials are discussed. Related research and perspectives may provide valuable references for designing and modifying effective NSF-based and other natural biomaterials. STATEMENT OF SIGNIFICANCE: There exist many reviews about mulberry silk fibroin (MSF) biomaterials and their biomedical applications, while that about nonmulberry silk fibroin (NSF) biomaterials is scarce. Compared with MSF, NSF exhibits unique arginine-glycine-aspartic acid sequences with promising cell adhesion enhancing effect, which makes NSF more suitable for cell culture and tissue regeneration related applications. Focusing on these advanced NSF biomaterials, this review has systematically compared the structure and properties of MSF and NSF, and emphasized the unique properties of NSF. Following that, the effective construction strategies for NSF-based biomaterials are summarized, and their recent applications in cell behavior regulations and tissue regenerations are highlighted. Furthermore, current challenges and future perspectives for the fabrication and application of NSF-based biomaterials were discussed.

Esophageal stricture is a distressing issue for patients with early esophageal cancer following extensive endoscopic submucosal dissection (ESD), and the current steroid-based approaches are unsatisfactory for stricture prophylaxis. We evaluated the efficacy of oral hydrocortisone sodium succinate and aluminum phosphate gel (OHA) for stricture prophylaxis after extensive ESD.Patients undergoing 3/4 circumferential ESD were randomized to either the endoscopic loco-regional triamcinolone acetonide injection (ETI) plus oral prednisone group or the OHA group. The primary endpoint was incidence of esophageal stricture, and the secondary endpoints included adverse events (AEs) and endoscopic balloon dilations (EBDs).The incidence of esophageal stricture in OHA group (per-protocol analysis, 9.4%, 3/32; intention-to-treat analysis, 12.1%, 4/33) was significantly less than that of control group (per-protocol analysis, 35.5%, 11/31, P = 0.013; intention-to-treat analysis, 39.4%, 13/33, P = 0.011). Two sessions of EBD were necessary to release all strictures in the OHA group, while the similar EBDs (median 2, range 1-4) for 11 of the control. Operation-related AEs included infection (control vs. OHA group = 9.7% vs. 31.3%, P = 0.034), operation-related hypokalemia (19.4% vs. 31.3%, P = 0.278), perforation (3.2% vs. 3.1%), post-ESD hemorrhage (6.5% vs. 0%), and cardiac arrhythmia (0% vs. 6.3%). Steroid-related AEs included steroid-related hypokalemia (16.1% vs. 25%) and bone fracture (3.2% vs. 0%). Multivariate logistic regression analysis demonstrated that OHA was an independent protective factor for stricture (OR 0.079; 95%CI 0.011, 0.544; P = 0.01) and mucosal defect 11/12 circumference was an independent risk factor (OR 49.91; 95%CI 6.7, 371.83; P 0.001).OHA showed significantly better efficacy in preventing esophageal stricture after 3/4 circumferential ESD compared to ETI plus oral prednisone.

Generally, electrospun silk fibroin scaffolds collected by traditional plates present limited pore size and mechanical properties, which may restrict their biomedical applications. Herein, regenerated Antheraea pernyi silk fibroin (RASF) with excellent inherent cell adhesion property was chosen as a raw material and the conductive metal meshes were used as collectors to prepare modified RASF scaffolds by electrospinning from its aqueous solution. A traditional intact plate was used as a control. The morphology and mechanical properties of the obtained scaffolds were investigated. Schwann cells were further used to assess the cytocompatibility and cell migration ability of the typical scaffolds. Interestingly, compared with the traditional intact plate, the mesh collector with an appropriate gap size (circa 7 mm) could significantly improve the pore size, porosity and mechanical properties of the RASF scaffolds simultaneously. In addition, the scaffold collected under this condition (RASF-7mmG) showed higher cell viability, deeper cell permeation and faster cell migration of Schwann cells. Combined with the excellent inherent properties of ASF and the obviously enhanced scaffold cytocompatibility and mechanical properties, the RASF-7mmG scaffold is expected to be a candidate with great potential for biomedical applications.

Strong nonspecific protein/cell adhesion on conducting polymer (CP)-based bioelectronic devices can cause an increase in the impedance or the malfunction of the devices. Incorporating oligo(ethylene glycol) or zwitterionic functionalities with CPs has demonstrated superior performance in the reduction of nonspecific adhesion. However, there is no report on the evaluation of the antifouling stability of oligo(ethylene glycol) and zwitterion-functionalized CPs under electrical stimulation as a simulation of the real situation of device operation. Moreover, there is a lack of understanding of the correlation between the molecular structure of antifouling CPs and the antifouling and electrochemical stabilities of the CP-based electrodes. To address the aforementioned issue, we fabricated a platform with antifouling poly(3,4-ethylenedioxythiophene) (PEDOT) featuring tri(ethylene glycol), tetra(ethylene glycol), sulfobetaine, or phosphorylcholine (PEDOT-PC) to evaluate the stability of the antifouling/electrochemical properties of antifouling PEDOTs before and after electrical stimulation. The results reveal that the PEDOT-PC electrode not only exhibits good electrochemical stability, low impedance, and small voltage excursion, but also shows excellent resistance toward proteins and HAPI microglial cells, as a cell model of inflammation, after the electrical stimulation. The stable antifouling/electrochemical properties of zwitterionic PEDOT-PC may aid its diverse applications in bioelectronic devices in the future.

Bio-memristors constitute candidates for the next generation of non-volatile storage and bionic synapses due to their biocompatibility, environmental benignity, sustainability, flexibility, degradability, and impressive memristive performance. Silk fibroin (SF), a natural and abundant biomaterial with excellent mechanical, optical, electrical, and structure-adjustable properties as well as being easy to process, has been utilized and shown to have potential in the construction of bio-memristors. Here, we first summarize the fundamental mechanisms of bio-memristors based on SF. Then, the latest achievements and developments of pristine and composited SF-based memristors are highlighted, followed by the integration of memristive devices. Finally, the challenges and insights associated with SF-based bio-memristors are presented. Advances in SF-based bio-memristors will open new avenues in the design and integration of high-performance bio-integrated systems and facilitate their application in logic operations, complex circuits, and neural networks.

A novel biomaterial ink consisting of regenerated silk fibroin (SF) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized bacterial cellulose (OBC) nanofibrils was developed for 3D printing lung tissue scaffold. Silk fibroin backbones were cross-linked using horseradish peroxide/H2O2 to form printed hydrogel scaffolds. OBC with a concentration of 7wt% increased the viscosity of inks during the printing process and further improved the shape fidelity of the scaffolds. Rheological measurements and image analyses were performed to evaluate inks printability and print shape fidelity. Three-dimensional construct with ten layers could be printed with ink of 1SF-2OBC (SF/OBC = 1/2, w/w). The composite hydrogel of 1SF-1OBC (SF/OBC = 1/1, w/w) printed at 25 °C exhibited a significantly improved compressive strength of 267 ± 13 kPa and a compressive stiffness of 325 ± 14 kPa at 30% strain, respectively. The optimized printing parameters for 1SF-1OBC were 0.3 bar of printing pressure, 45 mm/s of printing speed and 410 μm of nozzle diameter. Furthermore, OBC nanofibrils could be induced to align along the print lines over 60% degree of orientation, which were analyzed by SEM and X-ray diffraction. The orientation of OBC nanofibrils along print lines provided physical cues for guiding the orientation of lung epithelial stem cells, which maintained the ability to proliferate and kept epithelial phenotype after 7 days’ culture. The 3D printed SF-OBC scaffolds are promising for applications in lung tissue engineering. Electronic supplementary material The online version of this article (10.1007/s10570-020-03526-7) contains supplementary material, which is available to authorized users.

Although MXenes is highly attractive as anode materials of lithium ion batteries, it sets a bottleneck for higher capacity of the V2CTx MXene due to the limited interlayer space and the derived surface terminations. Herein, the cation intercalation and ion-exchange were well employed to achieve a K+ and Ca2+ intercalated V2CTx MXene. A larger interlayer distance and low F surface terminations were thereof obtained, which accelerates the ion transport and promotes the delicate surface of V2CTx MXene. As a result, a package of enhanced capacity, rate performance and cyclability can be achieved. Furthermore, the ion exchange approach can be extended to other 2D layered materials, and both the interlayer control and the surface modification will be achieved.

Rapid vascularization is very important in tissue engineering. Bladder acellular matrix (BAM) with inherent bioactive factors, a natural extracellular matrix (ECM) derived biomaterial, has been widely used as a scaffold to facilitate the repair and reconstruction of urinary tissues. However, the application of the traditional BAM scaffold has been limited due to the dense structure. To investigate the angiogenic potential of BAM, BAM hydrogels with tailored porous structures were prepared in this study by tuning BAM concentrations (4, 6, and 8 mg/mL). The 6 mg/mL BAM hydrogel was loaded with porcine iliac endothelial cells (PIECs), and their angiogenic potential was analyzed

Two-body correlations of the isotope-resolved light and heavy clusters are measured in $^{86}$Kr+$^{\rm 208}$Pb reactions at 25 MeV/u. The yield and kinetic variables of the $A=3$ isobars, triton and $^3$He, are analyzed in coincidence with the heavy clusters of $7\le A \le 14$ emitted at the earlier chance. While the velocity spectra of both triton and $^3$He exhibit scaling behavior over the type of the heavy clusters, the yield ratios of ${\rm t/^3He}$ correlate reversely to the neutron-to-proton ratio $N/Z$ of the latter, showing the ping-pong modality of the $N/Z$ of emitted clusters. The commonality that the $N/Z$ of the residues keeps the initial system value is extended to the cluster emission in heavy ion reactions. The comparison of transport model calculations to the data is discussed.

MXene is a rising star of two-dimensional (2D) materials for energy relative applications, however, the traditional synthesis of MXene etched by hazard HF acid or LiF+HCl mixed solution is highly dangerous with the risk of splashing or pouring liquid solutions. In this work, we developed a water-free ionothermal synthesis of 2D Ti3C2 MXene via etching pristine Ti3AlC2 MAX in low-cost choline chloride and oxalic acid based deep eutectic solvents (DES) with the presence of NH4F, thus it was highly safe and convenient to operate solid precursor and product materials at room temperature. Benefited from the low vapor pressure and solvating properties of DES, the prepared Ti3C2 (denoted as DES-Ti3C2) possessed a high purity up to 98% compared with 95% for HF etched Ti3C2 (denoted as HF-Ti3C2). Notably, an expanded interlayer spacing of 1.35 nm could be achieved due to the intercalation of choline cations in DES-Ti3C2, larger than that of HF-Ti3C2 (0.98 nm). As a result, the DES-Ti3C2 anodes exhibited enhanced lithium storage performance, such as high reversible capacity of 208 mAh g−1 at 0.5 A g−1, and long cycle life over 400 times, outperforming most reported pure MXene anodes. The ionothermal synthesis of MXene developed here may pave a new way to safely prepare other MXene for various energy relating applications.

In this work, a skin-core structure was designed, and three kinds of dual-wavelength fluorescent anti-counterfeiting (DWFA) fibers, including UV short-wavelength/UV long-wavelength, infrared/UV short-wavelength, and infrared/UV long-wavelength excitable DWFA fibers with skin-core structure, were spun using fluorescent powder/PP pellets as the skin material and pure PP as the core material. The results showed that these DWFA fibers emitted two different colors of light under excitation of two different wavelength lights, which exhibited higher anti-counterfeiting safety. Take UV short-wavelength/UV long-wavelength DWFA fibers, for example; the influence of skin-core ratio on the structure and properties of fibers were investigated, and then the luminous efficiency of DWFA fibers with skin-core structure and homogenous structure was compared. The microscope photos and 3D simulation of fluorescent powder in fibers by confocal laser scanning microscope showed that the fluorescent powders were basically distributed in the skin layer of fibers. The crystallinity degree and tensile strength of DWFA fibers with skin-core structure decreased first and then increased with the decrease in skin-core ratio, whereas elongation of fibers showed an increasing trend. Compared with homogenous DWFA fibers, the skin-core DWFA fibers exhibited higher luminous efficiency under the same fluorescent powder content.

Biodegradable/bioabsorbable electrically conducting wires have an important role in the development of next-generation wearable microelectronics and implantable devices. The implantable devices, including conducting wires, must be biocompatible and biodegradable to avoid an inflammatory response and a second surgery. However, most conducting wires used in biomedicine are still conventional metallic wires. Herein, a new conducting wire with excellent conductivity, bioabsorbability, biocompatibility, and low weight was prepared from natural polymer and chromium/aurum (10/140 nm), providing the possibility to construct a fully bioabsorbable implantable device. The conducting wire substrate prepared from silk nanoribbons and konjac glucomannan has excellent mechanical properties. The wire resistance was approximately 8 Ω cm−1. The conducting wire exhibits an impedance of 140 Ω at 1000 Hz, which remains largely unchanged when the wire was immersed in buffer solution for ten days. Connection with a biodegradable triboelectric nanogenerator provides an integrated fully bioabsorbable energy generation device with a maximum output power density of 314.3 mW m−2. Compared with conventional metallic wires, this conducting wire has a higher transmission efficiency and biodegradability, better biocompatibility, and is more lightweight. This conducting wire and the integrated fully bioabsorbable energy generation device may be used in the fields of wearable electronics and implantable bioelectronics.

An Fe(OTf)3-catalyzed intramolecular hydroarylation of arene-alkynes with high functional group tolerance has been reported, affording a series of phenanthrene derivatives efficiently. A low catalytic amount of Fe(OTf)3 is applied in this reaction. This transformation provides a convenient and practical method for the preparation of phenanthrenes. Keywords: Hydroarylation, Cyclization, Phenanthrene, Iron catalysis, Lewis acid

High chemical oxygen demand (COD) and a strong color, which primarily originates from desizing and dyeing operations, are two major removal objectives in textile wastewater treatment. In this study, crosslinking-induced precipitation via the covalent bonding between –OH groups of PVA and vinyl sulfone groups of reactive dyes is proposed to simultaneously remove poly(vinyl alcohol) (PVA) and reactive dyes. Due to the nucleophilic addition reaction under an alkaline condition, PVA polymers can be efficiently crosslinked by dye molecules and destabilized in the presence of alkali and Na2SO4. Additionally, due to the high coagulation efficiency under the alkaline conditions, MgSO4 was used as a coagulant to facilitate the removal of the residual color after precipitation. After a two-step process, whereby coagulation was followed by crosslinking-induced precipitation, the maximum efficiencies of the removal of COD, PVA, and color attained 88.9%, 86.3%, and 99.2%, respectively, when the PVA monomer/RB5 mole ratio was 400. We hope that this technically feasible, highly efficient, and cost-effective process provides a basis for the practical application of the simultaneous treatment of desizing and dyeing wastewater.