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Recently, ionic conductive hydrogels have been developed in the field of energy-storage devices owing to their unique properties, such as high ionic conductivity, mechanical flexibility, liquid-leakage-free operation, and stability.

Human T-cell leukemia virus 1 (HTLV-1) causes adult T-cell leukemia (ATL), but the mechanism underlying its initiation remains elusive. In this study, ORP4L was expressed in ATL cells but not in normal T-cells. ORP4L ablation completely blocked T-cell leukemogenesis induced by the HTLV-1 oncoprotein Tax in mice, whereas engineering ORP4L expression in T-cells resulted in T-cell leukemia in mice, suggesting the oncogenic properties and prerequisite of ORP4L promote the initiation of T-cell leukemogenesis. For molecular insight, we found that loss of miR-31 caused by HTLV-1 induced ORP4L expression in T-cells. ORP4L interacts with PI3Kδ to promote PI(3,4,5)P3 generation, contributing to AKT hyperactivation; NF-κB–dependent, p53 inactivation-induced pro-oncogene expression; and T-cell leukemogenesis. Consistently, ORP4L ablation eliminates human ATL cells in patient-derived xenograft ATL models. These results reveal a plausible mechanism of T-cell deterioration by HTLV-1 that can be therapeutically targeted.

Polymer hydrogel electrolytes combine the advantages of solvent-free solid electrolytes and liquid electrolytes, with a specific ion migration rate, excellent flexibility and safety. However, the critical limitation to the application...

The treatment of bacterial infections is becoming increasingly challenging with the emergence of antimicrobial resistance. Thus, the development of antimicrobials with novel mechanisms of action is much needed. Previously, we designed several cationic main-chain imidazolium compounds and identified the polyimidazolium PIM1 as a potent antibacterial against a wide panel of multidrug-resistant nosocomial pathogens, and it had relatively low toxicity against mammalian epithelial cells. However, little is known about the mechanism of action of PIM1. Using an oligomeric version of PIM1 with precisely six repeating units (OIM1-6) to control for consistency, we showed that OIM1-6 relies on an intact membrane potential for entry into the bacterial cytoplasm, as resistant mutants to OIM1-6 have mutations in their electron transport chains. These mutants demonstrate reduced uptake of the compound, which can be circumvented through the addition of a sub-MIC dose of colistin. Once taken up intracellularly, OIM1-6 exerts double-stranded DNA breaks. Its potency and ability to kill represents a promising class of drugs that can be combined with membrane-penetrating drugs to potentiate activity and hedge against the rise of resistant mutants. In summary, we discovered that cationic antimicrobial OIM1-6 exhibits an antimicrobial property that is dissimilar to the conventional cationic antimicrobial compounds. Its killing mechanism does not involve membrane disruption but instead depends on the membrane potential for uptake into bacterial cells so that it can exert its antibacterial effect intracellularly. Ministry of Education (MOE) Nanyang Technological University National Supercomputing Centre (NSCC) Singapore Published version This study was supported by the Ministry of Education, Singapore, under its MOE AcRF Tier 3 Award of MOE2018-T3-1-003. M.Y. acknowledges the support of the MOE Ph.D. scholarship under the MOE AcRF Tier 3 Award (MOE2018-T3-1-003). C.H.K. acknowledges the support of an NTU Ph.D. scholarship. Y.M. acknowledges the support of the Singapore MOE Tier 1 Grant RG27/21 and the Singapore National Supercomputing Center (NSCC).

The persistent challenge in Zn-ion batteries is the decomposition of coordinated water around Zn2+-induced side reactions and dendrite growth on Zn anode, leading to short lifespans. This situation is even worse in fiber-shaped Zn-ion batteries (FZIBs). Their curved and complex surface structure makes it even challenging to stabilize Zn anode via existing strategies. Herein, we address this dilemma via cost-effective citrate anion (Cit3−) additives which work as a tridentate chelating agent to regulate electrolytes on the molecular level. Synchrotron X-ray absorption fine structure analyses reveal that Cit3− manipulates the solvation shell of Zn2+ by forming [ZnCit(H2O)3]− chelate complexes. Combining with density functional theory calculation, for the first time, we demonstrate that Cit3− facilitates dehydration in [ZnCit(H2O)3]−, passivates remaining coordinated water via mitigating H O bond (H2O) elongation by 77.7%, suppresses Zn2+ transfer kinetics, homogenizes Zn2+ distribution at interfaces, enabling ∼500% extended lifespan. Based on this, we developed high-performance FZIBs by coupling Zn/carbon fiber anodes with highly conductive polypyrrole/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate fiber (∼3700 S cm−1) cathodes. Further mechanism study suggests that polypyrrole provides extra charge storage capacity by accommodating dual ions, i.e., Zn2+ and SO42−. The obtained quasi-solid-state FZIB possesses excellent performance for practical applications.

Antimicrobial resistance is a global threat. In addition to the emergence of resistance to last resort drugs, bacteria escape antibiotics killing by forming complex biofilms. Strategies to tackle antibiotic resistance as well as biofilms are urgently needed. Wall teichoic acid (WTA), a generic anionic glycopolymer present on the cell surface of many Gram-positive bacteria, has been proposed as a possible therapeutic target, but its druggability remains to be demonstrated. Here we report a cationic glycosylated block co-β-peptide that binds to WTA. By doing so, the co-β-peptide not only inhibits biofilm formation, it also disperses preformed biofilms in several Gram-positive bacteria and resensitizes methicillin-resistant Staphylococcus aureus to oxacillin. The cationic block of the co-β-peptide physically interacts with the anionic WTA within the cell envelope, whereas the glycosylated block forms a nonfouling corona around the bacteria. This reduces physical interaction between bacteria-substrate and bacteria-biofilm matrix, leading to biofilm inhibition and dispersal. The WTA-targeting co-β-peptide is a promising lead for the future development of broad-spectrum anti-biofilm strategies against Gram-positive bacteria. Ministry of Education (MOE) Nanyang Technological University Accepted version This research is supported by the Singapore Ministry of Education under its Singapore Ministry of Education Academic Research Fund Tier 3 (Grants MOE2013-T3-1-002 and MOE2018-T3-1-003) and Nanyang Technological University

Natural nacre built up with a brick-and-mortar architecture, exhibiting extraordinary strength and toughness, provides an inspiration to construct high-performance multifunctional films for flexible energy storage and portable electrical devices. In the present work, a nacre-mimetic graphene-based film (CNT@PANI/rGO/TA) is fabricated following this idea, wherein electroactive biomass tannin (TA) serves as glue, accompanied by the “mortar” polyaniline wrapped carbon nanotubes (CNT@PANI), to stick the reduced graphene oxide (rGO) “bricks” together. Benefiting from the thin layer of PANI on CNTs, the CNT@PANI nanowires intercalate into the rGO interlayers thus interlocking the nanosheets, and resulting in a well-defined porous multilayered structure. The obtained CNT@PANI/rGO/TA film exhibits both high mechanical strength (174.6 MPa) and toughness (9.17 MJ m−3). Meanwhile, the all-solid-state flexible supercapacitor assembled with CNT@PANI/rGO/TA demonstrates a high capacitance of 548.6 F cm−3 and an outstanding rate performance of 70.5% from 1 A g−1 to 50 A g−1. Even at −40 °C, the specific capacitance of the supercapacitor is up to 454.9 F cm−3, approximately 83% of the capacitance delivered at room temperature. The strategy of using electroactive biomass as glue to construct a nacre-mimetic graphene-based film with high strength, toughness and energy storage performance is proved to be straightforward and effective.

To endow high mechanical strength and thermal stability aramid nanofibers (ANF) with novel functionality will lead to great applications. Herein, a strategy to generate covalent bonds among components towards obtaining uniform ANF/reduced holey graphene oxide (ANF/rHGO) and ANF/rHGO/polyaniline (ANF/rHGO/PANI) hydrogels with high mechanical properties is proposed through solvent exchange gelation and subsequent hydrothermal treatment. The as-prepared ANF/rHGO and ANF/rHGO/PANI hydrogels demonstrate excellent recoverability at high compressive strength of 20.2 and 13.8 kPa with a strain of 34.4% and 30.6%, respectively, compared to a recoverability of 92.5% at a strain of ∼20% for ANF hydrogels. Moreover, ANF/rHGO and ANF/rHGO/PANI aerogels possess fast and high oil absorption capacity of 38.9–64.1 g g−1 and 24.5–44.0 g g−1, respectively. ANF/rHGO and ANF/rHGO/PANI films obtained after vacuum-drying exhibit a high tensile strength of 121.4 and 95.5 MPa, respectively. Additionally, ANF/rHGO/PANI thin films present good selective absorption of visible light by controlling the doping level of PANI. ANF/rHGO/PANI aerogel films prepared by freeze-drying are assembled into flexible solid-state symmetric supercapacitors and deliver a favorable specific capacitance of 200 F g−1, a desirable capacitance retention of 98.9% after 2500 mechanical bending cycles and an approximately 100% capacitance retention even after keeping tensile force for 15 h. The as-prepared hydrogels, aerogels and derived films with such excellent performances are promising for applications in oil pollution removal, optical filters and flexible load-bearing energy storage devices.

Fast tool servo (FTS) machining is a highly efficient approach to generate optical freeform surfaces and microstructures, where submicrometric form accuracy and nanometric surface finish are often required. The on-machine surface measurement (OMSM) is an enabling technology to improve the metrology efficiency and machining accuracy of FTS. However, the integration of the OMSM with FTS on an ultra-precision machine is a huge challenge due to the complexity of data processing and synchronization. In this paper, a dedicated controller is in-house developed with data processing algorithms for the integration. The effectiveness of the proposed method is demonstrated through the successful fabrication and measurement of a freeform lens array.

The development of a novel preparation strategy for 3D porous network structures with an aligned channel or wall is always in challenge. Herein, a 3D porous network composed of an aligned graphene-based wall is fabricated by a confined self-assembly strategy in which holey reduced graphene oxide (HrGO)/lignin sulfonate (Lig) composites are orientedly anchored on the framework of the Lig/single-wall carbon nanotube (Lig/SWCNT) hydrogel by vacuum-assisted filtration accompanied with confined self-assembly and followed with hydrothermal treatment. After freeze drying, the obtained ultralight Lig/SWCNT/HrGO

The preparation of graphene-based aerogels with excellent mechanical strength, elasticity, and compressibility is still a challenge. Herein, we demonstrate a robust, elastic, and lightweight graphene/aramid nanofiber/polyaniline nanotube (rGO/ANF/PANIT) aerogel that is prepared by mixing graphene oxide (GO), ANF, and PANIT dispersions, followed by thermal treatment at 90 °C, freeze-drying, and a low-temperature annealing process. The PANIT bonds the graphene sheets tightly, benefitting the formation of composite gels. The ANF tightly interconnects the graphene sheets and further reinforces the composite network framework significantly, hence endowing rGO/ANF/PANIT composite aerogels with robust mechanical property. The prepared aerogels present a low density of ∼12 mg cm

In this letter, amorphous silicon nitride (Si3N4) film grown by inductively coupled plasma chemical vapor deposition (ICPCVD) method is used as the photosensitive layer of deep ultraviolet (DUV) detection, whose thickness and roughness are 200 nm and 0.92 nm, respectively. The transverse symmetrical photoconductive detector with interdigital electrodes spacing of $4~\mu \text{m}$ is fabricated by photolithography, exhibiting ultrahigh photo-to-dark current ratio (PDCR) more than 105, fast fall speed of 127 ms and also a satisfying responsivity of 1.09 mA/W. This work lays a foundation for further researches on Si3N4 in photonics and electronics.

Wearable supercapacitors, as one of the most important power supplies for wearable electronics, require excellent flexibility and deformability and a structure that is not easily delaminated. In th...

There are many holes and oxygen groups in reduced graphene oxide (rGO), which influences its conductivity, packing density, mechanical performance, thermal properties, and optical absorption. To co...

Phospholipase C (PLC) isoforms play central roles in signaling cascades by cleaving PIP2 into the second messengers IP3 and DAG. In this study, to our knowledge, we uncover that ORP5L interacts physically with PLCγ1 in T cells, extracts PIP2 from the plasma membrane via its ORD domain (OSBP-related domain), presents it to PLCγ1 (enabling IP3 generation), and eventually maintains intracellular Ca2+ homeostasis. Through this mechanism, ORP5L promotes T cell proliferation in a Ca2+-activated NFAT2-dependent manner. To our knowledge, our study uncovers a new key function of ORP5L as a critical cofactor for PLCγ1 catalysis and its crucial role in human T cell proliferation.

Methicillin-resistant Staphylococcus aureus (MRSA) is a significant cause of drug-resistant infections. Its propensity to develop biofilms makes it especially resistant to conventional antibiotics. We present a novel nanoparticle (NP) system made from biocompatible F-127 surfactant, tannic acid (TA), and biguanide-based polymetformin (PMET) (termed FTP NPs), which can kill MRSA biofilm bacteria effectively in vitro and in vivo and which has excellent biocompatibility. FTP NPs exhibit biofilm bactericidal activity—ability to kill bacteria both inside and outside biofilm—significantly better than many antimicrobial peptides or polymers. At low concentrations (8–32 μg/mL) in vitro, FTP NPs outperformed PMET with ∼100-fold (∼2 log10) greater reduction of MRSA USA300 biofilm bacterial cell counts, which we attribute to the antifouling property of the hydrophilic poly(ethylene glycol) contributed by F-127. Further, in an in vivo murine excisional wound model, FTP NPs achieved 1.8 log10 reduction of biofilm-associated MRSA USA300 bacteria, which significantly outperformed vancomycin (0.8 log10 reduction). Moreover, in vitro cytotoxicity tests showed that FTP NPs have less toxicity than PMET toward mammalian cells, and in vivo intravenous injection of FTP NPs at 10 mg/kg showed no acute toxicity to mice with negligible body weight loss and no significant perturbation of blood biomarkers. These biguanide-based FTP NPs are a promising approach to therapy of MRSA infections. ASTAR (Agency for Sci., Tech. and Research, S’pore) MOE (Min. of Education, S’pore) NMRC (Natl Medical Research Council, S’pore) MOH (Min. of Health, S’pore) Accepted version

To improve machining capability of diamond turning of hierarchical structured surfaces, fast-tool-servo (FTS) turning using a sharp point diamond cutting tool (tool tip width

Leukemia stem cells (LSCs) propagate leukemia and are responsible for the high frequency of relapse of treated patients. The ability to target LSCs remains elusive, indicating a need to understand the underlying mechanism of LSC formation. Here, we report that miR-31-5p is reduced or undetectable in human LSCs compared to hematopoietic stem progenitor cells (HSPCs). Inhibition of miR-31-5p in HSPCs promotes the expression of its target gene FIH , encoding FIH [factor inhibiting hypoxia-inducing factor 1α (HIF-1α)], to suppress HIF-1α signaling. Increased FIH resulted in a switch from glycolysis to oxidative phosphorylation (OXPHOS) as the predominant mode of energy metabolism and increased the abundance of the oncometabolite fumarate. Increased fumarate promoted the conversion of HSPCs to LSCs and initiated myeloid leukemia-like disease in NOD-Prkdc scid IL2rg tm1 /Bcgen (B-NDG) mice. We further demonstrated that miR-31-5p inhibited long- and short-term hematopoietic stem cells with a high frequency of LSCs. In combination with the chemotherapeutic agent Ara-C (cytosine arabinoside), restoration of miR-31-5p using G7 poly (amidoamine) nanosized dendriplex encapsulating miR-31-5p eliminated LSCs and inhibited acute myeloid leukemia (AML) progression in patient-derived xenograft mouse models. These results demonstrated a mechanism of HSC malignant transformation through altered energy metabolism and provided a potential therapeutic strategy to treat patients with AML.

Correction for ‘Polymers as advanced antibacterial and antibiofilm agents for direct and combination therapies’ by Zhangyong Si et al., Chem. Sci., 2022, 13, 345–364, https://doi.org/10.1039/D1SC05835E.

Monoclinic gallium oxide ( β-Ga2O3) has attracted much attention from the fields of optoelectronic and electronic devices owing to the properties of wide bandgap, great breakdown field strength, as well as the economic advantages of low-cost growth of large-size single crystals. Here, the basic photophysical properties including absorption (free-carrier absorption and band-edge absorption) and reflection (phonon polaritons and exciton polaritons) of differently doped β-Ga2O3 with diverse carrier concentrations are studied in detail. The unpolarized reflection spectra of differently doped β-Ga2O3 crystals are well fitted based on the non-polarized reflection model. Besides, according to analysis, the longitudinal–transverse splitting energy of β-Ga2O3 direct excitons is estimated to be as high as 100 meV, reflecting the strong interaction between light and excitons. It is hoped that this work can provide beneficial reference for a comprehensive understanding on the spectral physical characteristics of β-Ga2O3, so as to deepen and expand the basic recognition of this material in the aspect of photophysical properties.

The freeform surfaces including both the aspherical and prismatic concave/convex have been widely utilized in optical, electronical, and biomedical areas. Most recently, it is reported that grinding with structured wheels provides new possibility to generate patterns on hard and brittle materials. This paper reports the latest research progress on micro-grooving glass ceramic using laser structured bronze bond diamond grinding wheels. A nanosecond pulse laser is firstly integrated into an ultra-precision machine tool and used for the in-line conditioning of super abrasive grinding wheels, i.e. truing, dressing, and profiling/texturing. Meanwhile, an offset compensation method, considering the shifting depth of focus (DoF) at different laser irradiation position, is proposed to accurately generate various profiles on the periphery of the grinding wheels. Three types of patterns (riblets, grooves, and pillars) are successfully fabricated on the ceramic substrate using the laser textured grinding wheels. The results indicate that the integrated laser system offers high flexibility and accuracy in shaping super abrasive grinding wheels, and the grinding using textured grinding wheels provide a promising solution to generate functional structures on hard and brittle materials.

Oxysterol-binding protein–related protein (ORP) 4L acts as a scaffold protein assembling CD3-e, G-αq/11, and PLC-β3 into a complex at the plasma membrane that mediates inositol (1,4,5)-trisphosphat...

Single metal-organic coordination polymers have limited functions as precursors for porous carbon electrode materials. The construction of bimetallic organic coordination polymers can effectively utilize the advantages of each single metal-organic coordination polymer to improve the performance of the derived carbon materials. Herein, High performance nitrogen-doped porous carbon (BCFe–Ni) have been produced by directly carbonizing bimetallic organic coordination polymers formed by 4,4′-bipyridine (BPD) reaction with FeCl3 and NiCl2. The BCFe–Ni exhibits high nitrogen content (12.66 at%), large specific surface area (1049.51 m2 g−1) and hierarchical porous structure, which contributes to an excellent gravimetric specific gravity of 320.5 F g−1 and 108% of specific capacitance retention after 10000 cycles. The BCFe–Ni assembled symmetrical supercapacitor shows an energy density of 18.3 W h kg−1 at a power density of 350 W kg−1. It is expected that the as-prepared N-doped porous carbon derived from bimetallic-organic coordination polymer is a promising electrode material for high performance energy storage devices. Keywords: Bimetallic-organic coordination polymers, N-doped porous carbon, High specific surface area, Supercapacitors

Driven by the ever increasing demand in function integration, more and more next generation high value-added products, such as head-up displays, solar concentrators and intra-ocular-lens, etc., are designed to possess freeform (i.e., non-rotational symmetric) surfaces. The toolpath, composed of high density of short linear and circular segments, is generally used in computer numerical control (CNC) systems to machine those products. However, the discontinuity between toolpath segments leads to high-frequency fluctuation of feedrate and acceleration, which will decrease the machining efficiency and product surface finish. Driven by the ever-increasing need for high-speed high-precision machining of those products, many novel toolpath interpolation and smoothing approaches have been proposed in both academia and industry, aiming to alleviate the issues caused by the conventional toolpath representation and interpolation methods. This paper provides a comprehensive review of the state-of-the-art toolpath interpolation and smoothing approaches with systematic classifications. The advantages and disadvantages of these approaches are discussed. Possible future research directions are also offered.

Summary: Leukemia stem cells (LSCs) are a rare subpopulation of abnormal hematopoietic stem cells (HSCs) that propagates leukemia and are responsible for the high frequency of relapse in therapies. Detailed insights into LSCs’ survival will facilitate the identification of targets for therapeutic approaches. Here, we develop an inhibitor, LYZ-81, which targets ORP4L with high affinity and specificity and selectively eradicates LCSs in vitro and in vivo. ORP4L is expressed in LSCs but not in normal HSCs and is essential for LSC bioenergetics and survival. It extracts PIP2 from the plasma membrane and presents it to PLCβ3, enabling IP3 generation and subsequent Ca2+-dependent bioenergetics. LYZ-81 binds ORP4L competitively with PIP2 and blocks PIP2 hydrolysis, resulting in defective Ca2+ signaling. The results provide evidence that LSCs can be eradicated through the inhibition of ORP4L by LYZ-81, which may serve as a starting point of drug development for the elimination of LSCs to eventually cure leukemia. : Zhong et al. report that abnormal expression of ORP4L is essential for leukemia stem cell survival; it enables IP3 generation by extracting and presenting PIP2 from the plasma membrane to PLCβ3 for hydrolysis. The compound LYZ-81, which blocks this process via targeting ORP4L, selectively eradicates leukemia stem cells. Keywords: leukemia stem cell, OSBP-related protein 4L, PIP2 hydrolysis, Ca2+ signaling, energy metabolism, therapy

Recently, natural biomass has been widely explored as a precursor to prepare carbon materials due to its abundant, low-cost, and renewable character. Herein, a series of high-performance heteroatom...

Carbon cloth (CC) is widely used as a freestanding substrate for energy storage devices, due to its high conductivity, special porous network, and good mechanical flexibility. However, it is still challenging to fully utilize the space of CC to achieve a high mass loading of electroactive materials and ultimately fulfill high electrochemical performance. Herein, a new strategy is proposed to fill the gaps and voids in CC with a functionalized graphene hydrogel (FGH) through one-step hydrothermal treatment of oxidized CC submerged in a mixture of graphene oxide and p-phenylenediamine. The as-prepared FGH/functionalized CC is then adopted as a scaffold to load a lignosulfonate/polyaniline (Lig/PANI) hydrogel via in situ polymerization of aniline in the presence of lignosulfonate, and thereby an integrated textile (Lig/PANI/FGH/FCC) is obtained. The symmetric supercapacitor assembled with Lig/PANI/FGH/FCC electrodes and 1 M H2SO4 electrolyte shows a superior areal capacitance of 1223 mF cm−2 and an energy density of 169.9 μW h cm−2 at 2 mA cm−2. Moreover, the assembled flexible all-solid-state supercapacitor presents competitive energy density (160.6 μW h cm−2 at 1000 μW cm−2) and excellent flexibility. This design of anchoring a hierarchical porous conductive network in a macroscopic macropore framework paves a new avenue towards high mass loading and low interfacial resistance in macroporous material-based electrodes for high-performance energy storage devices.