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Melamine was grafted to a polyurethane (PU) frame and utilized for cross-linking PU via amino groups. The degree of crosslinking and the solution viscosity increased notably after grafting melamine due to the formation of crosslinks. The thermal transition of the soft segment was not significantly affected, but the glass transition was observed at a slightly higher temperature in case of the grafted melamine. Melamine-mediated crosslinking increased not only the breaking tensile stress but also the shape recovery performance of PU. In addition, crosslinked PU was more flexible at low temperature than unmodified PU. Overall, melamine-mediated crosslinking improved the tensile resistance to stress, the recovery tendency to the initial shape, and the flexibility with minor changes in the thermal transition, tensile strain, and shape retention at a low temperature.

For the global commercialization of highly efficient and stable perovskite solar cells (PSCs), it is necessary to effectively suppress the formation of various defects acting as nonradiative recombination sources in perovskite light-harvesting materials. Interfacial defects between the charge-selective layer and the perovskite are easily formed in the solution process used to fabricate perovskite films. In addition, owing to the difference in thermal expansion coefficients between the substrate and the perovskite film, internal residual tensile stress inevitably occurs, resulting in increased nonradiative recombination. Herein, a simple compositional engineering scheme for realizing efficient and stable PSCs, which incorporates acetamidinium bromide (AABr) as an additive into the MAPbI3 lattice, is proposed. As an additive, AABr has been found to provide synergistic multiple passivation for both internal and interfacial defects. AABr was found to effectively release the tensile strain of the MAPbI3 film by forming a structure stabilized by NH–I hydrogen bonds, as evidenced by calculations based on density functional theory (DFT). Furthermore, the incorporated AABr additives created a charge carrier recombination barrier to enhance charge collection capability by reducing interfacial defects. Accordingly, a power conversion efficiency (PCE) of 20.18% was achieved using a planar device employing AABr-incorporated MAPbI3. This was substantially higher than the 18.32% PCE of a pristine MAPbI3-based device. Notably, unencapsulated PSCs using AABr-incorporated MAPbI3 absorbers exhibited excellent long-term stability, maintaining >95% of initial PCE up to 1200 hours in ambient air.

We first observed the spin-to-charge conversion due to both the inverse Rashba-Edelstein effect (IREE) and inverse spin-Hall effect in a holey multilayer molybdenum disulfide (MoS2) intermediate layer in a Pt/YIG structure via LSSE measurements under nonequilibrium magnetization. We found an enhancement of approximately 238%, 307%, and 290% in the longitudinal spin Seebeck effect (LSSE) voltage, spin-to-charge current, and thermoelectric (TE) power factor, respectively, compared with the monolayer MoS2 interlayer in a Pt/YIG structure. Such an enhancement in the LSSE performance of Pt/holey MoS2/YIG can be explained by the improvement of spin accumulation in the Pt layer by induced spin fluctuation as well as increased additional spin-to-charge conversion due to in-plane IREE. Our findings represent a significant achievement in the understanding of spin transport in atomically thin MoS2 interlayers and pave the way toward large-area TE energy-harvesting devices in two-dimensional transition metal dichalcogenide materials.

Conjugated microporous polymer (CMP)-based energy-storage materials were developed for pseudocapacitors. Nanoparticulate CMP (N-CMP) with an average diameter of 41±4 nm was prepared through kinetic growth control in the Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodobenzene. The N-CMP is rich in a diphenylacetylene moiety in its chemical structure. Through the FeCl3 -catalyzed oxidation of diphenylacetylene moieties, N-CMP with benzil moieties (N-CMP-BZ) was prepared and showed enhanced electrochemical performance as an electrode material of pseudocapacitors, compared with CMP, CMP-BZ, and N-CMP. In model studies, the benzil was redox active and showed two-electron reduction behavior. The excellent electrochemical performance of N-CMP-BZ is attributable to the enhanced utilization of functional sites by a nanosize effect and the additional redox contribution of benzil moieties.

Flexible and metal-economical electromagnetic interference (EMI) shielding films were fabricated based on microporous organic polymer (MOP) chemistry. MOP with amino groups (MOP-A) could be introduced to the surface of poly(ethylene terephthalate) (PET) fibers. Due to the microporosity and amino groups of MOP-A, Ag+ could be easily incorporated into PET@MOP-A. Through Ag-catalyzed electroless Cu deposition, PET@MOP-A@Cu films were fabricated. The morphological and chemical structures of the PET@MOP-A@Cu were characterized by scanning electron microscopy, X-ray diffraction studies, and X-ray photoelectron spectroscopy. Among the films, the PET@MOP-A@Cu-40 with 41 wt % Cu (a thickness of 0.64 μm) showed excellent EMI shielding performance with 64.3-73.8 dB against an EM of 8-12 GHz. Moreover, it showed retention of the original EMI shielding performance against 1000 bending (R = 5 mm) tests.

Graft polymerization of poly(ethylene glycol) methyl ether acrylate (PEGA) onto polyurethane (PU) was conducted to improve its water compatibility, tensile mechanical strength, shape memory, and low-temperature flexibility properties, as well as to control its water vapor permeability (WVP). Control PUs containing free poly(PEGA) were also prepared to compare with the poly(PEGA)-grafted PUs. The water compatibility of PU notably improved due to the grafting of poly(PEGA) based on water contact angle results. The soft segment melting temperature and glass transition temperature were not changed with the increase in the PEGA content. The tensile strength of PU sharply increased due to the grafting of poly(PEGA), whereas the free poly(PEGA) in the control PUs did not cause a similar increase. The maximum strain of PU was not affected by the grafting of poly(PEGA). The shape recovery at 0°C significantly increased compared with the unmodified PU. The low-temperature flexibility of PU improved, and the WVP through the PU membrane was reduced by the grafting of poly(PEGA) onto PU.

Epoxy polymers composed of bisphenol A (BPA) and epichlorohydrin (ECH) were grafted onto polyurethane (PU) using the graft-polymerization method to prepare the epoxy PU hybrid polymer. The main series contained the epoxy polymer grafted onto PU; however, the epoxy polymer was not bound to PU in the control series. The breaking tensile stress steeply increased at low BPA and ECH contents and then decreased as more BPA and ECH were included in the main series, whereas the control series did not display an incline in the breaking tensile stress irrespective of the BPA and ECH contents. The percent shape recovery also steeply increased after the grafting of epoxy polymer in the main series but increased at a slower rate in the control series. The flexibility of the main series at a freezing temperature was not enhanced compared with the plain PU because the grafted epoxy polymers did not effectively disrupt the molecular interaction between PUs. Therefore, the grafting of epoxy polymers noticeably enhanced the breaking tensile strength and percent shape recovery of PU.

The antifungal agent carbendazim and the water-compatible functional group 2,4,6-tris(dimethylaminomethyl)phenol (TDMP) were jointly grafted to polyurethane (PU) to develop a water-compatible antifungal PU. The water compatibility of the PU surface improved strikingly after the protonation of TDMP, as confirmed by water contact angle tests. The combined grafting of carbendazim and TDMP affected the melting and glass transition of soft segments and sharply increased the tensile stress and shape recovery capability. Carbendazim was selected as a grafted antifungal functional group due to its wide effective range of antifungal activity and its large production volume. PUs with grafted carbendazim and TDMP completely suppressed the growth of a mixture of fungi, unlike ordinary PU. Therefore, the joint grafting of both carbendazim and TDMP led to improved water compatibility, breaking tensile stress, shape recovery capability, and antifungal activity.

The poly(ethylene glycol) phenyl ether acrylate (PEPA) monomers are graft-polymerized onto polyurethane (PU), and its impacts on water compatibility, chain packing, tensile stress, and shape recovery capability are evaluated. The grafted poly(PEPA)s slightly increase the degree of cross-linking due to the linking between themselves. The water compatibility (water contact angle, water swelling, and water vapor permeation) are affected slightly by the grafted poly(PEPA). The grafted poly(PEPA) does not notably influence the melting of soft segments, but the crystallization of soft segments is reduced significantly. The grafted poly(PEPA) does not significantly affect the glass transition of soft segments. The grafted poly(PEPA) notably increases the breaking tensile stress with the increase in PEPA content, but the breaking tensile strain decreases slowly with increasing PEPA content. The grafted poly(PEPA) rapidly improves the shape recovery capability of PU and slowly decreases the shape retention capability with the increase in PEPA content. Therefore, the grafted poly(PEPA) slightly modifies the water compatibility but notably enhances the breaking tensile stress and shape recovery capability of PU.

Sodium ion batteries (SIBs) have attracted considerable attention as an alternative to Li ion batteries (LIBs) because of the sustainable sodium resources and similar chemistry to LIBs. On the other hand, the larger and heavier sodium results in unfavorable sodium ion storage capacity. In this study, an inexpensive precursor-based conversion material, FeS2, was synthesized as a nanostructured pyrite crystal

Products of lupin, a leguminous plant belonging to genus Lupinus, have high protein contents and are consumed in Mediterranean and Middle East countries. However, quinolizidine alkaloids (Q...

Perpendicular cardo structural units were inserted into a polyurethane (PU) framework from the pH indicator (phenolphthalein (PP), phenol red (PR), or bromocresol green (BG)) sharing a triphenylmethyl group. The thermal transitions, mechanical properties, pH-sensitive color change, and low temperature flexibility of the PU modified with the cardo structural units were compared with those of the ordinary PU. Slight cross-linking between PU chains was performed because the insertion of the indicator moieties deteriorated the mechanical properties. The breaking tensile stress and shape recovery capability at 0 °C of the BG-PU series surpassed those of the PP-PU and PR-PU series. The inserted pH indicator moieties did not show the color change under different pH conditions because the isomerization under basic conditions was blocked. Among the three series of PUs, the BG-PU demonstrated the best low temperature flexibility compared with that of the PP-PU and PR-PU due to the functional groups on the phenyl rings of BG. Insertion of a cardo structural unit from the pH indicator reduced the molecular interaction between PU chains.

The so-called colloidal template synthesis has been applied to the preparation of surface-engineered nanoadsorbents. Colloidal microporous organic network nanotemplates (C-MONs), which showed a high surface area (611 m2 g-1 ) and enhanced microporosity, were prepared through the networking of organic building blocks in the presence of poly(vinylpyrrolidone) (PVP). Owing to entrapment of the PVP in networks, the C-MONs showed good colloidal dispersion in EtOH. MoS2 precursors were incorporated into the C-MONs and heat treatment afforded core-shell-type C@MoS2 nanoparticles with a diameter of 80 nm, a negative zeta potential (-39.5 mV), a high surface area (508 m2 g-1 ), and excellent adsorption performance towards cationic dyes (qmax =343.6 and 421.9 mg g-1 for methylene blue and rhodamine B, respectively).

A hydrophobic polyurethane (PU) was altered to obtain a hydrophilic characteristic using the graft polymerization of 2-(dimethylamino)ethyl methylmethacrylate (DAMA) onto the PU surface and the subsequent ionization of the dimethylamino group on poly(DAMA). The grafted poly(DAMA) chain influenced numerous properties, such as the cross-link density, thermal transitions of soft segments, and tensile and shape memory characteristics. The grafting of poly(DAMA) noticeably enhanced the breaking tensile stress and shape recovery capability through the cross-linking between the grafted poly(DAMA)s, but the breaking tensile strain and the shape retention did not noticeably decline after the grafting of poly(DAMA). Additionally, the poly(DAMA)-grafted PU exhibited a significant enhancement in its low temperature flexibility and antifungal effectiveness against a mixture of fungi.

Phthalic acid (PA) was grafted onto polyurethane (PU) in the PA series due to its rigid aromatic structure and carboxyl groups, but PA was simply blended with PU in the control CPA series. The cros...

Celastrol, a pentacyclic triterpene, is the most potent antiobesity agent that has been reported thus far1. The mechanism of celastrol’s leptin-sensitizing and antiobesity effects has not yet been elucidated. In this study, we identified interleukin-1 receptor 1 (IL1R1) as a mediator of celastrol’s action by using temporally resolved analysis of the hypothalamic transcriptome in celastrol-treated DIO, lean, and db/db mice. We demonstrate that IL1R1-deficient mice are completely resistant to the effects of celastrol in leptin sensitization and treatment of obesity, diabetes, and nonalcoholic steatohepatitis. Thus, we conclude that IL1R1 is a gatekeeper for celastrol’s metabolic actions. IL1R1 is a gatekeeper for celastrol’s metabolic actions.

In this work, we present the nanohybrid electrode (termed as p-h-SnO2/GA) of porous hollow SnO2 (p-h-SnO2) integrated on the surface of graphene aerogel (GA) for anodes with large lithium storage capacity. Selective etching of Ni from Ni3Sn2 nanoparticles produces the porous hollow nanostructure of SnO2, which is important for providing the structural flexibility that can accommodate the volume change of SnO2 during the lithiation and delithiation processes. GA also serves as a buffer for the volume change of SnO2 and induces effective charge transports through its interconnected porous network structure. These combined advantages of p-h-SnO2 and GA enable a reversible Li storage capacity as high as 620 mAh g−1 with ∼100% Coulombic efficiency at a specific current of 50 mA g−1 over 200 charge–discharge cycles and ∼71% of rate-retention capability over the specific currents of 100 mA g−1–1 A g−1. It makes this nanohybrid electrodes an attractive candidate for high-performance lithium ion battery anode.

The surface of polyurethane (PU) was modified by the graft polymerization of N,N-dimethylaminoethyl methacrylate (DAMA) and acrylic acid (AA) to enhance its water compatibility. Portions of poly(DAMA) and poly(AA) could be ionized by mutual acid–base neutralization and could notably improve the surface hydrophilicity of PU. The water contact angle, water absorption, and water vapor permeation test results jointly demonstrate the increase in water compatibility resulting from the inclusion of poly(DAMA) and poly(AA) in PU. The melting and glass transition temperatures of PU were not significantly influenced by the grafting of poly(DAMA) and poly(AA) onto PU. Small portions of the grafted poly(DAMA) and poly(AA) were involved in the cross-linking of PU, which sharply increased the shape recovery and the breaking tensile stress while maintaining high shape retention and breaking tensile strain.

Recycled tire rubber is an environmentally and economically beneficial material. Ground tire rubber (GTR) as a filler in a polymer matrix was used as an ink material (composite material) for material extrusion in a 3D printing process. The maximum allowable amount of GTR incorporated into the mixture without significantly altering the rheological behavior of the ink was set. Printability investigations revealed that pressure and speed show linear and power relationships, respectively, to the line width for three different amounts of GTR. Moreover, the post-curing time of 30 min at 115 °C was set as the full-cure condition to achieve polymerization of 80% or more for the 3D printed parts. Unidirectional tensile testing demonstrated that 3D printed specimens exhibit no degradation in tensile strength when compared to molded specimens. Moreover, printability and mechanical properties of functionalized GTR were investigated to determine if this material exhibits enhanced mechanical strength. Unidirectional tensile tests show that the maximum tensile strength for specimens with functionalized GTR was 20% higher than in specimens with non-functionalized GTR. In conclusion, 3D printing of GTR composites shows promise for using recycled GTR to create 3D structures with rubber-like properties.

Flexible nanohybrid paper electrode (termed as C-I) consisting of multi-walled carbon nanotubes (MWCNTs) and indium sulfide (In2S3) nanoplates is formed via a simple vacuum-assisted assembly and used as an anode for sodium-ion batteries (SIBs). In2S3 nanoplates which are well distributed on and bound to the MWCNTs provide a high Na storage capacity of the nanohybrid electrode as high as 410 mAh g−1 at a specific current of 50 mA g−1 over 100 charge/discharge cycles and ∼97% of rate-retention capability over the specific currents of 50 mA g−1 to 1 A g−1 for at least 50 charge/discharge cycles. Particularly, when In2S3 in the form of nanoplates was added to MWCNTs, the electrochemical performances are considerable as compared to those of bulk In2S3 or MWCNTs film electrodes. This highlights the importance of nanohybrid approach in overcoming the intrinsic complication of In2S3, i.e., the agglomeration of In2S3 into bulk form during assembly, followed by annealing. For C-I nanohybrid electrode, capacitive contribution (∼95%) rather than insertion contribution (∼5%) is predominant during charge/discharge process. The nanohybrid paper electrode is robust and thus retains capacity even under repeated mechanical deformation (flat-bent-flat cycles), demonstrating the potential of the electrode being used for flexible and wearable energy storage.

Gel electrolytes were synthesized by the formation of microporous organic polymers in the presence of 0.077–0.77 M LiClO4 and N-methylpyrrolidone. Electrochromic devices fabricated using the gel electrolytes showed enhanced operation stability, compared with those fabricated using liquid electrolytes, which is attributable to the efficient separation of working viologens from counting molecules.

Three-dimensional (3D) printing has enabled benchtop fabrication of customized bioengineered constructs with intricate architectures. Various approaches are being explored to enable optimum integration of such constructs into the physiological environment including addition of bioactive fillers. In this work, we incorporated a corticosteroid drug, dexamethasone (Dex), in a low modulus polyester (SC5050) and examined the effect of Dex incorporation on solvent-, initiator-, and monomer-free pneumatic extrusion-based 3D printing of the polymer. Dex-SC5050 interactions were characterized by plotting thermodynamic binary phase diagrams based on the Flory-Huggins theory. The effect of Dex composition on the 3D printability of the SC5050 polyester was examined by rheological characterization and by image analysis of each layer of the 3D printed scaffolds. The drug release and the degradation of the polymer from the 3D printed scaffolds was used to analyze the effect of Dex composition on the performance of the 3D printed scaffolds. We found that Dex was insoluble in SC5050 polyester at relevant 3D printing temperatures and the insoluble drug particles physically reinforced the polymer, increasing the viscosity and the shear modulus of the base polymer. In addition, the reinforcing effect improved the shape fidelity of the printed filaments and the overall quality of the scaffolds. The Dex particles demonstrated a two-phase release, with an initial burst release and a slower sustained release of drug under in vitro conditions. To investigate preliminary host response of the 3D printed SC5050 scaffolds for tissue engineering applications, the printed scaffolds were implanted subcutaneously in Sprague-Dawley rats for 6 weeks and examined for fibrous tissue formation, infiltration of cells, and vascularization into the pores of the scaffolds.

Infection is one of several factors that can delay normal wound healing. Antibacterial wound dressings can therefore promote normal wound healing. In this study, we prepared an antibacterial wound dressing, consisting of visible light-cured methacrylated collagen (ColMA) hydrogel and a 2-hydroxypropyl-beta-cyclodextrin (HP-β-CD)/triclosan (TCS) complex (CD-ic-TCS), and evaluated its wound healing effects in vivo. The 1H NMR spectra of ColMA and CD-ic-TCS revealed characteristic peaks at 1.73, 5.55, 5.94, 6.43, 6.64, 6.84, 6.95, 7.31, and 7.55 ppm, indicating successful preparation of the two material types. In addition, ultraviolet–visible (UV–vis) spectroscopy proved an inclusion complex formation between HP-β-CD and TCS, judging by a unique peak observed at 280 cm−1. Furthermore, ColMA/CD-ic-TCS exhibited an interconnected porous structure, controlled release of TCS, good biocompatibility, and antibacterial activity. By in vivo animal testing, we found that ColMA/CD-ic-TCS had a superior wound healing capacity, compared to the other hydrocolloids evaluated, due to synergistic interaction between ColMA and CD-ic-TCS. Together, our findings indicate that ColMA/CD-ic-TCS has a clinical potential as an antibacterial wound dressing.

We prepared a drug carrier which consisted of injectable methacrylated glycol chitosan (MGC) hydrogel, and a conjugate of 6-monodeoxy-6-monoamino-&beta, cyclodextrin&sdot, hydrochloride (6-NH2-&beta, CD&sdot, HCl), polyethylene glycol (PEG), and folic acid (FA) for the local delivery and improved cellular uptake of paclitaxel (PTX) (MGC/CDPF-ic-PTX). CDPF refers to a conjugate of 6-NH2-&beta, HCl, PEG, and FA. The anti-cancer effect was investigated using a xenograft mouse model. As controls, the animal study on MGC/PTX and MGC/CD-ic-PTX was performed. The swelling ratio of all samples was analyzed for 7 days, and it showed a gradual increase for 3 days and a maintained state afterward. From the release result, the MGC-based samples have an initial burst for 1 day and a sustained release for 7 days. Results of cytotoxicity and animal study showed the biocompatibility and superior anti-cancer effect of MGC/CDPF-ic-PTX against breast cancer. Furthermore, histological results showed the anti-cancer capacity of MGC/CDPF-ic-PTX against breast cancer. These findings suggest that MGC/CDPF-ic-PTX has clinical potential for breast cancer therapy.

We report the analysis of deoxyribonuclease (DNase) activity by conjugation-free fluorescence polarisation in a droplet-based microfluidic chip. DNase is a DNA cleaving enzyme and its activity is important in the maintenance of normal cellular functions. Alterations in DNase activity have been implicated as the cause of various cancers and autoimmune diseases. To date, various methods for the analysis of DNase activity have been reported. However, they are not cost effective due to the requirement of large sample volumes and the need for the conjugation of fluorescent dyes. In this study, we have used ethidium bromide (EtBr), a DNA intercalating reagent, as a fluorescent reporter without any prior conjugation or modification of DNA. Degradation of DNA by DNase 1 was monitored at a steady state by making changes in the fluorescence polarisation of EtBr in droplets with a volume of 330 picolitre at a 40 hertz frequency under visible light. Using this technique, we successfully determined the half-maximal inhibitory concentration (IC50) of ethylenediaminetetraacetic acid (EDTA) for the inhibition of DNase 1 activity to be 1.56 ± 0.91 mM.

ObjectiveThis study aimed to compare the efficacy between bipolar radiofrequency ablation (RFA), using twin internally cooled wet (TICW) electrodes, and switching monopolar RFA, using separable clustered (SC) electrodes, in the treatment of recurrent hepatocellular carcinoma (HCC) after locoregional treatment.Materials and methodsIn this single-center, two-arm, parallel-group, randomized controlled study, we performed a 1:1 random allocation on eligible patients with recurrent HCC after locoregional treatment, to receive TICW-RFA or SC-RFA. The primary endpoint was the minimum diameter of the ablation zone per unit ablation time. Secondary endpoints included other technical parameters, complication rate, technical success and technique efficacy, and clinical outcomes.ResultsEnrolled patients were randomly assigned to the TICW-RFA group (n = 40) or SC-RFA group (n = 37). The two groups did not show significant differences in the primary endpoint, the minimum diameter of the ablation zone per unit ablation time was 2.71 ± 0.98 mm/min and 2.61 ± 0.96 mm/min in the TICW-RFA and SC-RFA groups, respectively (p = 0.577). Total RF energy delivery (11.75 ± 9.04 kcal vs. 22.61 ± 12.98 kcal, p < 0.001) and energy delivery per unit time (0.81 ± 0.49 kcal/min vs. 1.45 ± 0.42 kcal/min, p < 0.001) of the TICW-RFA group were less than those of the SC-RFA group. No procedure-related death or major complications occurred. Technical success was achieved in all patients in both groups, and technique efficacy rates were 100% (46/46) in the TICW-RFA group and 95.0% (38/40) in the SC-RFA group (p = 0.213). The 1-year and 2-year cumulative LTP rates were 11.8% and 24.2%, respectively, in the TICW-RFA group, and 8.6% and 18.1%, respectively, in the SC-RFA group (p = 0.661).ConclusionIn this single-center randomized controlled study from a Korean tertiary referral hospital, TICW-RFA demonstrated similar therapeutic efficacy and safety profile for recurrent HCC after locoregional treatment compared with SC-RFA.Trial registrationClinicalTrials.gov (NCT03806218).

Poly(N-isopropylacrylamide) (poly(NIPAM)) was grafted onto polyurethane (PU) using a graft-polymerization method to develop a thermo-responsive PU and to investigate the impact on cross-link density, solution viscosity, soft segment thermal transitions, tensile properties, shape memory effect, and water vapor permeation through PU membrane. The soft segment crystallization peak sharply decreased with the increase in NIPAM content, whereas the glass transition temperature (Tg) slightly increased with the increase of NIPAM content. The breaking tensile stress rapidly increased with the increase in NIPAM content due to the cross-linking effect between the grafted poly(NIPAM) chains, whereas the strain at break did not significantly decreased as the NIPAM content increased. The shape recovery at 10°C rapidly increased from 46.9% for plain PU to above 90% after the grafting of poly(NIPAM) onto PU, and the shape retention at −25°C slightly decreased with the increase in NIPAM content. Finally, the graft...

Initiator-free, photocurable, low-toxicity, viscoelastic polymer inks are attractive materials for creating low-modulus 3D-printed elastomeric biomedical constructs. In this work, we describe the synthesis, characterization, and 3D printing/crosslinking of a hydrophilic coumarin-PEG polyester (CPP). The viscoelastic CPP melt can be extruded at room temperature and deposited into layer-by-layer patterns. Upon UV irradiation, the coumarin pendant groups undergo [2 + 2] photocyclization, creating a thermoset network without the use of monomers, photoinitiators or propagating radicals. Voxel-voxel adhesion experiments between crosslinked and uncrosslinked material were performed to examine interfacial dynamics in a native, unperturbed state, and various attempts at 3D printing were made to assess the impact of printing conditions on the ultimate printed structure. Rheological analysis indicates a transition point where elastic behavior overtakes viscous behavior at increasing shear rate. It is hypothesized that this transition point corresponds with changes in interface formation from “sticky” to “bouncy” behavior in voxel-voxel adhesion and 3D printing processes. Tensile-mode dynamic mechanical analysis (DMA) and X-Ray microtomography (microCT) experiments reveal interfacial defect accumulation that results in deterioration of macroscopic structural and mechanical properties.

The aim of this study was to compare the retentive properties of an attachment with a nylon insert and an attachment with a polyetherketoneketone (PEKK) insert on two-implant mandibular overdentures during simulated masticatory loadings and insertion/removal cycles.Two attachment systems with nylon inserts or PEKK inserts were investigated, including nylon/low, nylon/medium, nylon/high, PEKK/x-low, PEKK/low, PEKK/medium, and PEKK/high. The canine region of edentulous mandibular overdenture models was retained with two implant analogs through two different stud attachments at interimplant angulations of 0 and 20 degrees. The simulated mastication and insertion/removal cycles were 400,000 cyclic loadings and 1,080 times of insertion/removal. Wear patterns and deformations on the attachment surface were analyzed with scanning electron microscopy.At 0 and 20 degrees, initial retentive force was highest in nylon/high and lowest in PEKK/x-low. Final retentive force was highest in PEKK/high and PEKK/medium at 0 and 20 degrees, respectively, and PEKK/x-low was lowest at both angulations. At 0 degrees, nylon/low, nylon/medium, PEKK/x-low, and PEKK/low displayed a significant increase in retention (P.05), and nylon/high and PEKK/medium showed a significant decrease in retention (P.05), except PEKK/high, which exhibited no significant decrease (P.05). At 20 degrees, nylon/low and PEKK/x-low increased retention significantly (P.05), and nylon/medium, nylon/high, PEKK/low, PEKK/medium, and PEKK/high decreased retention significantly (P.05). Patrices of both attachment systems barely showed detectable abrasion, while matrices revealed severe wear and surface deformation. Nylon inserts particularly displayed more noticeable wear and deformation than PEKK inserts.Within the limitations of this investigation, the attachment system with a PEKK insert indicated less abrasion and retention change than the attachment system with a nylon insert on both paralleled implants and axially tilted implants under 400,000 cyclic loadings and 1,080 insertion/removal cycles for 1 year.

Grafting of niclosamide or salicylanilide onto polyurethane (PU) was executed to develop antifungal effectiveness and barnacle repelling capability in seawater compared with underivatized PU. The PU surface was simultaneously modified to improve the surface hydrophilicity by inserting dimethylolpropionic acid into PU frame or by grafting recycled polyols onto PU. Surface modifications of PU significantly affected its properties, such as cross-link density, tensile and shape memory properties, and flexibility under freezing conditions relative to the unmodified PU. The modification of PU surface also notably influenced the glass transition and the melting and crystallization related to soft segments. The breaking tensile stress and the shape recovery were enhanced significantly after the grafting of polyol due to chemical cross-linking, whereas the breaking tensile strain was not reduced. Some PU samples demonstrated complete antifungal effectiveness against a mixture of fungi, and barnacle growth on PU films was limited in the specifically modified PUs.

Despite the pivotal role of MYC in tumorigenesis, the mechanisms by which it promotes cancer aggressiveness remain incompletely understood. Here, we show that MYC transcriptionally upregulates the ubiquitin fusion degradation 1 (UFD1) gene in T-cell acute lymphoblastic leukemia (T-ALL). Allelic loss of ufd1 in zebrafish induces tumor cell apoptosis and impairs MYC-driven T-ALL progression but does not affect general health. As the E2 component of an endoplasmic reticulum (ER)-associated degradation (ERAD) complex, UFD1 facilitates the elimination of misfolded/unfolded proteins from the ER. We found that UFD1 inactivation in human T-ALL cells impairs ERAD, exacerbates ER stress, and induces apoptosis. Moreover, we show that UFD1 inactivation promotes the proapoptotic unfolded protein response (UPR) mediated by protein kinase RNA-like ER kinase (PERK). This effect is demonstrated by an upregulation of PERK and its downstream effector C/EBP homologous protein (CHOP), as well as a downregulation of BCL2 and BCLxL. Indeed, CHOP inactivation or BCL2 overexpression is sufficient to rescue tumor cell apoptosis induced by UFD1 knockdown. Together, our studies identify UFD1 as a critical regulator of the ER stress response and a novel contributor to MYC-mediated leukemia aggressiveness, with implications for targeted therapy in T-ALL and likely other MYC-driven cancers.

This work reports the thinnest and smallest hollow N-doped carbon boxes among recently reported hollow N-doped carbon materials. Hollow and N-rich microporous organic networks (H-NMONs) were prepared by the azide–alkyne Huisgen cycloaddition of tetra(4-ethynylphenyl)methane and 1,4-diazidobenzene on the surface of Cu2O nanocubes and the successive acid etching of inner Cu2O. The Cu2O nanocubes played roles of templates and networking catalysts. The networking reaction generated N-rich triazole rings in the MON. Heat treatment of H-NMONs under argon resulted in the formation of hollow N-doped carbon boxes (H-NCBs). The diameter and shell thickness of H-NCBs were 130 and 12 nm, respectively. The H-NCBs showed superior electrochemical performance in H2SO4 electrolyte as energy storage materials for supercapacitors, compared with that in KOH electrolyte. Among the H-NCBs, H-NCB-900 which was obtained by the heat treatment of H-NMON at 900 °C showed the best performance with capacitances of 286 and 251 F/g at ...

Conjugated microporous polymer films (CMP-Fs) bearing tetraphenylethylene moieties showed aggregation-induced emission behavior, which can be utilized for the emission quenching-based sensing of nitrotoluenes. In this work, macroporous CMP-Fs (MA-CMP-Fs) were engineered using assembled silica spheres as templates. The MA-CMP-Fs showed much better sensing performance toward nitrotoluenes with Stern–Volmer constants (KSV) of up to 1.39 × 105 M−1, compared with CMP-Fs (KSV up to 5.57 × 104 M−1). The sensing performance of the MA-CMP-F is superior to those of recent emissive CMP materials (KSV in the range of 2.08 × 103 to 6.78 × 104 M−1 for nitroarenes) in the literature, which is attributable to the additional macroporosity of the CMP-F. Also, we demonstrated that various functional CMP films with macroporous inner structures can be developed using tailored building blocks.

Layered double hydroxides (LDHs) are promising photocatalysts for water oxidation, essential to generate solar fuels, but their limited accessible reaction sites, slow charge transfer, and activity degradation are yet to be overcome. As a solution to overcome these drawbacks, we report nanosheets of mono or dual layers derived via nitrogen plasma exfoliation of anion layers from NiAl LDHs. Moreover, such a sheet has rich O vacancies resulting in decreased Ni–O and shortened Ni–metal bonds. Furthermore, doped nitrogen leads to metal–N and N–O bonds along with oxynitrides. With O vacancies facilitating adsorption of water oxidation intermediates onto low-coordinated Ni and the doped N pulling electrons from water oxidation intermediates, the ultrathin nanosheets assembled on hematite nanorods are found to outperform the activity of hematite by about 2 fold and the charge transfer of LDH nanoplates assembled on hematite by about 4 fold, while showing excellent activity retention close to 100% in a long-term stability test.

Redox active 1,4-bis(3-phenylpropynoyl)benzene moieties were incorporated into a hollow conjugated microporous polymer via carbonylative Sonogashira coupling of 1,3,5-triethynylbenzene with 1,4-diiodobenzene in the presence of carbon monoxide. The resultant redox active material showed enhanced energy storage performance for pseudocapacitors.