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We report that the presence of superstructure ordering serves as an important building block in securing the long-term stability of the oxygen redox activity in O2-type lithium-rich layered oxides.

The advancement of electrolyte systems has enabled the development of high-performance Li metal batteries (LMBs), which have tackled intractable dendritic Li growth and irreversible Li plating/stripping. In particular, the robust electrode–electrolyte interfaces created by electrolyte additives inhibit the deterioration of the cathode and the Li metal anode during repeated cycles. This paper reports the application of electrode–electrolyte interface modifiers, namely lithium nitrate (LiNO3) and lithium difluoro(bisoxalato) phosphate (LiDFBP) as a N donor and F donor, respectively. LiDFBP and LiNO3 with different electron-accepting abilities construct a mechanically robust, LiF-rich inner solid electrolyte interphase (SEI) and ion-permeable, Li3N-containing outer SEI layers on the Li metal anode, respectively. A well-structured dual-layer SEI capable of transporting Li+ ions is formed on the Li metal anode, while the cathode–electrolyte interface (CEI) on the LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode is strengthened. Ether-based electrolytes containing LiDFBP and LiNO3 lead to a long cycle life (600 cycles) of Li|NCM811 full cells at C/2 with 80.9% capacity retention and a high Coulombic efficiency (CE) of 99.94%. Structural optimization of the SEI and CEI provides an opportunity for advancing the practical uses of LMBs.

We studied the intercalation chemistry of graphitic carbon nitride (gCN), combining theory and experimental methods. A series of new alkali-ethylenediamine-gCN products were prepared using a one-po...

The reversibility of lithium plating/stripping should be guaranteed in lithium metal batteries. Seriously localized lithium growth during plating leads to the dendritic evolution of lithium metal due to the uneven current distribution on the electrically conductive surface. Artificial protective layers covering electrodes (e.g., polymer film on copper foil) have been used to narrow the gap of the current density between positions on the conductive surface. Herein, we incorporated an active ingredient to attract lithium ions into the dendrite-suppressing layer. Pyridinic nitrogen of graphitic carbon nitride (g-C3N4) served as the lithium ion affinity center. Conformation of the nitrogen changed from pyridinic to graphitic in the presence of lithium ions, which confirms the coordination of lithium ion to the pyridinic nitrogen. Moreover, lithium ion conduction was facilitated in the presence of g-C3N4 layer probably via a site-to-site hopping mechanism. Lithium metal was plated between the g-C3N4 layer and the copper current collector (or the lithium metal). The homogeneous lithium nucleation expected from the active role of the pyridinic nitrogen (lithium ion affinity and facilitated ionic conduction) suppressed the dendritic growth of lithium metal and decreased the overpotential required for the initial metal nucleation. Due to the top-down ion flux regulation on the uppermost surface (or tip) of lithium metal, the reversibility of lithium plating/stripping was dramatically improved.

A sodium-ethylenediamine graphite intercalation compound (Na(ethylenediamine)C15: "GIC") made from graphite flakes was used to study the microwave absorption performance of a GIC for the first time. Compared with the pristine graphite flakes, the neighboring layers in this GIC are pillared by Na(ethylenediamine)+ and possess a larger layer distance and improved electrical conductivity. Owing to the electrical conductivity of this GIC, only half of the loading content, compared to graphite flakes, is needed to achieve an outstanding absorption of -75.6 dB at 9.25 GHz (10.0 wt % GIC in paraffin in a 4.0 mm thick sample), but for graphite, 20.0 wt % is required for an absorption of -37.6 dB.

Sodium-metal-based seawater batteries (SWB) are considered an attractive energy storage system because of the cost-effective nature of Na+ ions. However, the high overpotential and low power output...

Notwithstanding the numerous density functional studies on the chemically induced transformation of multilayer graphene into a diamond-like film carried out to date, a comprehensive convincing experimental proof of such a conversion is still lacking. We show that the fluorination of graphene sheets in Bernal (AB)-stacked bilayer graphene grown by chemical vapour deposition on a single-crystal CuNi(111) surface triggers the formation of interlayer carbon-carbon bonds, resulting in a fluorinated diamond monolayer ('F-diamane'). Induced by fluorine chemisorption, the phase transition from (AB)-stacked bilayer graphene to single-layer diamond was studied and verified by X-ray photoelectron, UV photoelectron, Raman, UV-Vis and electron energy loss spectroscopies, transmission electron microscopy and density functional theory calculations.

Although substrate composition can influence the chemical reactivity of graphene, substrate lattice orientation provides a valuable alternative. The effect of Cu surface orientation on the reactivi...

Iron titanate (Fe2TiO5) is a promising photoanode material due to a narrow band gap, appropriate band edges, robustness and abundance. However, its performance is limited because of its low conductivity and short hole diffusion length. Precisely controlled, a few Fe2TiO5 layers of inverse opal structure (IOS) is fabricated via a layer-by-layer self-assembly and then treated by hybrid microwave annealing to produce a highly crystalline, yet IOS morphology-preserved Fe2TiO5 photoanode film for solar water splitting. The highly transparent Fe2TiO5 IOS film shows a greatly enhanced visible light harvesting, higher density of catalytically more active crystal planes, and many single crystalline nanoplates grown on the IOS architecture, relative to a reference planar film prepared under similar conditions. As a result, the optimized ‘exactly’ three Fe2TiO5 layers IOS electrode with a sacrificial gallium oxide underlayer and a ternary (Ni2CoFe)OOH co-catalyst records 2.08 mA cm−2 at 1.23 VRHE under 1 sun (100 mW cm−2) irradiation, which is the highest photocurrent density produced by Fe2TiO5 photoanode up to date.

The development of active and stable non-precious-metal electrocatalysts for energy conversion reactions involving hydrogen and oxygen has been of pivotal importance for realizing a clean-energy-based society. As a class of non-precious-metal electrocatalysts, cobalt- and nitrogen-codoped carbon (Co–N/C) catalysts have shown promising activity for the hydrogen evolution reaction (HER). The further advancement of Co–N/C catalysts is, however, hindered by the poor understanding of their active sites; the typical preparation of Co–N/C catalysts involves high-temperature pyrolysis, yielding catalysts with a heterogeneous distribution of atomically dispersed Co–Nx sites and metallic Co nanoparticles encapsulated in graphitic carbon shells (Co@C). Further, kinetic insights into the HER on Co–N/C catalysts are lacking. In this work, we prepared a series of Co–N/C catalysts with controlled Co–Nx and Co@C site densities, which served as model catalysts for identifying the active sites for the HER. We found that th...

Antiphase boundaries (APBs) in 2D transition metal dichalcogenides have attracted wide interest as 1D metallic wires embedded in a semiconducting matrix, which could be exploited in fully 2D‐integrated circuits. Here, the anisotropic morphologies of APBs (i.e., linear and saw‐toothed APBs) in the nanoscale are investigated. The experimental and computational results show that despite their anisotropic nanoscale morphologies, all APBs adopt a predominantly chalcogen‐oriented dense structure to maintain the energetically most stable atomic configuration. Moreover, the effect of the nanoscale morphology of an APB on electron transport from two‐probe field effect transistor measurements is investigated. A saw‐toothed APB has a considerably lower electron mobility than a linear APB, indicating that kinks between facets are the main factors of scattering. The observations contribute to the systematical understanding of the faceted APBs and its impact on electrical transport behavior and it could potentially extend the applications of 2D materials through defect engineering to achieve the desired properties., Herein, the anisotropic nanoscale features of antiphase boundaries in 2H phase of transition metal dichalcogenides are investigated (i.e., saw‐toothed for transition metal‐facing and linear for chalcogen‐facing antiphase boundaries) in order to preserve the thermodynamically most stable atomic configurations. In addition, they have different in‐plane transport behavior because lots of kinks in the saw‐toothed antiphase boundary act as scattering centers.

Chlorine evolution reaction (CER) is a critical anode reaction in chlor-alkali electrolysis. Although precious metal-based mixed metal oxides (MMOs) have been widely used as CER catalysts, they suffer from the concomitant generation of oxygen during the CER. Herein, we demonstrate that atomically dispersed Pt−N4 sites doped on a carbon nanotube (Pt1/CNT) can catalyse the CER with excellent activity and selectivity. The Pt1/CNT catalyst shows superior CER activity to a Pt nanoparticle-based catalyst and a commercial Ru/Ir-based MMO catalyst. Notably, Pt1/CNT exhibits near 100% CER selectivity even in acidic media, with low Cl− concentrations (0.1 M), as well as in neutral media, whereas the MMO catalyst shows substantially lower CER selectivity. In situ electrochemical X-ray absorption spectroscopy reveals the direct adsorption of Cl− on Pt−N4 sites during the CER. Density functional theory calculations suggest the PtN4C12 site as the most plausible active site structure for the CER., Chlorine evolution reaction (CER) is a key electrochemical reaction for chemical, pulp, and paper industries, and water treatments. Here, the authors report that an atomically dispersed Pt−N4 site can catalyse CER with high activity and selectivity under a wide range of Cl– concentrations and pH.

Polyhedral structure has attracted attention as a promising morphology of bifunctional electrocatalysts, which is suitable for providing catalytic active facets. However, polyhedral metal oxides have been suffering from control of their morphology. Herein, we develop micrometer-sized polyhedral bismuth ruthenate pyrochlore (P-BRO) for Zn–air batteries, which achieve highly improved catalytic activity by development of (100), (110), and (111) planes regardless of particle size. To clarify the formation mechanism of polyhedral structure, in situ transmission electron microscopy analysis is performed at 1050 °C, resulting in observation of Ostwald ripening and facets formation. Furthermore, we reveal that A- and B-site cations on low-index facets of the P-BRO could mainly contribute to catalytic activity by first-principle calculations. For practical application, we performed Zn–air flow batteries, which could effectively remove precipitated zinc oxide particles on the surface of air electrode, resulting in ...

To unlock the potential of clathrates hydrate for versatile applications in energy and environmental application such as energy storage, gas separation, and novel functional materials, profound understanding of their hidden nature must be secured. In this study, we focused on the complex host–guest and heterogeneous guest–guest interactions occurring on the sH hydrates of 3,3-dimethyl-1-butanol with help gases of CH4 or CO2. The density functional theory calculations and spectroscopic experimental analyses showed that the dynamics of the large 3,3-dimethyl-1-butanol guest molecule as well as the host water frameworks of sH hydrate were significantly influenced by the type of gaseous co-guest molecules via complex host–guest and/or guest–guest interactions. The flexible hydrogen-bonded water framework underwent contraction or elongation in the O:H–O hydrogen and O–H polar-covalent bonds induced by distinct occupation patterns of the co-guest help gases, and it was observed that, depending on the type, the co-guest help gases triggered the transformation of torsional configuration of the hydrophobic moieties of the large 3,3-dimethyl-1-butanol guest molecule while the hydrophilic part was incorporated into the host water framework.

Cost-effective and environmentally friendly seawater-electrolyte-based batteries exhibit high energy density and demonstrate immense potential for use in future energy storage devices; however, lack of high-performance negative and positive electrodes significantly challenges their practical applications. In this study, N-doped and N,S-doped carbon nanospheres (referred to as NCSs and NSCSs, respectively) are synthesized via the pyrolysis of melanosomes, which is a bio-inspired polymer. Electrocatalytic activity measurements reveal the bifunctionality of the prepared catalysts. NSCSs exhibit a distinctively higher performance than NCSs when used as an air electrode in seawater batteries under ambient conditions (referred to as static mode hereafter). Further, due to the introduction of air flow into the seawater electrolyte (referred to as flow mode hereafter), NSCSs exhibit an improved cell discharge potential. The high performance of the cell is attributed to the high surface area, bifunctional electrocatalytic activity, generation of new active sites, improvement of spin density in NSCSs, and continuous flow of air to the electrolyte. The cell in the flow mode exhibits an overpotential gap of 0.56 V, a round-trip efficiency of 84%, a maximum power density of 203 mW g−1, and an outstanding cycling stability up to 100 cycles. The developed synthetic method provides an effective, scalable approach for doping binary or ternary atoms into the carbon host matrix, which can motivate further experimental and theoretical studies of electrode materials in various energy storage devices. In addition, the concept and results obtained by the introduction of air flow into the electrolyte can lead to the improvement of cell performance in terms of electrical energy efficiency, which can be exploited in various metal–air batteries.

Photocatalytic H2O2 production is one of the most promising methods because it is a safe and sustainable technique. However, the inactiveness of inorganic photocatalysts (TiO2) under visible light irradiation and severe photodecomposition of H2O2 on their surfaces result in low performance for solar H2O2 production. Here, we report for the first time, a hydrophobic organic/inorganic (polymer/TiO2) heterojunction photocatalyst, which not only can utilize visible light, but also suppress H2O2 decomposition. In the absence of a hole scavenger, the photogenerated H2O2 concentration of the poly(9,9-dioctylfluorene-alt-benzothiadiazole) (PFBT)/TiO2 heterojunction photocatalyst (67 µM) was >70 times higher than that of pristine PFBT polymer. Further, improvement of polymer hydrophobicity by fluorine substitution results in enhanced photogenerated H2O2 concentration (110.4 µM) on (Poly(9,9-dioctyl fluorine-alt-difluorobenzothiadiazole) (PF2FBT)/TiO2). The atomistic simulation studies substantiate that the low adsorption energy of H2O2 on the heterojunction and the surface shielding of TiO2 induced by the hydrophobicity of the fluorinated polymers significantly improve H2O2 production.

Low-cost oxygen evolution/reduction reaction (OER/ORR) catalysts are critically important for energy conversion/storage systems. Here, a porous carbon (PC) catalyst is prepared as a low-cost catalyst from grapefruit peel biowaste using a facile hydrothermal carbonization combined with a chemical activation process. When examined as an OER/ORR catalyst in seawater, the PC exhibits an unexpected, highly efficient catalytic activity. From density functional theory (DFT) calculations, we found that sp3-bonded carbon atoms, zigzag edges with or without –COOH and –OH, and armchair edges with –O– are responsible for its superior OER/ORR activity. The suitability of the PC as a catalyst is tested in the half-cell of a Na/seawater battery, which exhibits a decreased voltage gap of ∼0.47 V between charge and discharge voltage curves. This value is even lower than those of Pt/C (∼0.68 V), IrO2 (∼0.66 V) and MnO2 (∼0.73). Also, a full cell of the metal-free seawater battery is assembled using hard carbon and PC as an anode and a catalyst, respectively. The full cell shows a lower voltage gap (∼0.65 V) with the voltage efficiency of ∼83–84% and excellent cycle life over 100 cycles. Our results confirm PC derived from grapefruit peels as an alternative to expensive Pt/C and IrO2 catalysts for the OER/ORR activities in seawater batteries.

Binder-free and bifunctional electrocatalysts have vital roles in the development of high-performance metal–air batteries. Herein, we synthesized a vanadium oxide (VO2) nanostructure as a novel binder-free and bifunctional electrocatalyst for a rechargeable aqueous sodium–air (Na–air) battery. VO2 nanostructures were grown on reduced graphene oxide coated on carbon paper, which had a carambola morphology. We confirmed the bifunctional nature of VO2 nanostructures by analyzing their electrocatalytic activity associated with the oxygen reduction reaction and oxygen evolution reaction. The reaction pathway associated with electrocatalytic activity was also affirmed by computational modeling and simulation studies. Thereafter, an aqueous Na–air cell was built using novel binder-free VO2 nanostructures as the air electrode. The fabricated cell displayed a 0.64 V overpotential gap, 104 mW g−1 power density at 80 mA g−1 current density, 81% round trip efficiency and good cyclic stability up to 50 cycles.

8-Hydroxyquinoline (8-HQ), commonly known as oxine, is the most popular among the hydroxyquinolines due to its excellence in complex formation with metal ions and with a wide spectrum of pharmacological applications. 8-HQ and many of its derivatives are fluorogenic ligands when complexed with metal ions. Thus they are regularly used for detection, separation, and quantitative analysis of metal ions as well. For example when chelated with aluminum, the coordinated complex exhibits strong visible emission, which is applicable for the fabrication of organic light-emitting diodes. Although metal complexes with 8-HQ and its derivatives are fluorescent promising wide applications, the ligand itself, 8-HQ, is surprisingly a very weak fluorophore in most of the media, because of its short lifetime in the excited state. To address the nature of ultrashort-lived 8-HQ in the excited sate, we study its photochemical and photophysical processes in acidic, basic, and neutral aqueous media. Our results show that 8-HQ as well as its protonated and deprotonated forms, undergoes ultrafast excited-state proton transfer within femto-to-picoseconds to produce a tautomer as a product, the lifetime of which is also ultrashort. This can give a clue as to why metal complexes of 8-HQ generally show strong fluorescence whereas 8-HQ itself is rarely fluorescent in aqueous solutions; when 8-HQ binds to metal cations, the ligand is in the deprotonated (anionic) form, which cannot undergo the ultrafast proton transfer without generating the short-lived dark product, but survives much longer to tens of nanoseconds to “turn on” fluorescence.

The crystalline phase of layered transition metal dichalcogenides (TMDs) directly determines their material property. The most thermodynamically stable phase structures in TMDs are the semiconducting 2H and metastable metallic 1T phases. To overcome the low phase purity and instability of 1T-TMDs, which limits the utilization of their intrinsic properties, various synthesis strategies for 1T-TMDs have been proposed in phase-engineering studies. Herein, a facile and scalable synthesis of 1T-phase molybdenum disulfide (MoS2 ) via the molten-metal-assisted intercalation (MMI) approach is introduced, which exploits the capillary action of molten potassium and the difference between the electron affinity of MoS2 and the ionization potential of potassium. Highly reactive molten potassium metal can readily intercalate into the MoS2 interlayers, inducing an efficient phase transition from the 2H to 1T crystal structure. The ionic bonding between the intercalated potassium and sulfur lowers the energy barrier of the 1T-phase transition, enhancing the phase stability of the 1T crystals. Owing to the high purity and stability of the 1T phase, the electrocatalytic performance for the hydrogen evolution reaction is significantly higher in 1T-MoS2 (MMI) than in 2H-MoS2 and even in 1T-MoS2 synthesized using n-butyllithium.

Control over the morphology and crystallinity of metal halide perovskite materials is of key importance to enable high-performance optoelectronics. Here, a simple yet effective template-free self-assembly synthesis of perovskite granular wires with ultrahigh photodetectivity (3.17 × 1015 Jones) is reported. The 1D self-assembly of perovskite grains is driven by differences in the surface interaction energies of the granular facets. The superb photodetecting performance originates from extremely low dark current engendered by energetic barriers featuring unique band-edge modulation along the long axis of wire. Flexible photodetector arrays, fabricated by selectively placing perovskite granular wires onto pre-patterned electrode arrays on a transparent polymer substrate, show independently addressable photonic signal mapping with remarkably high detectivity, photoconductive gain, and responsivity. The "self-assembled nanograin engineering" strategy developed in this study provides a viable method for the development of high-performance perovskite photodetectors and can be extended to other integrated optoelectronic systems.

Replacing noble-metal-based oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts is the key to developing efficient Zn-air batteries (ZABs). Here, a homogeneous ternary Ni

A series of fluorescent molecular rotors obtained by introducing two rotational groups ("rotators"), which exhibit different rotational and electron-donating abilities, are discussed. Whereas the control molecular rotor, PH, includes a single rotator (the widely used phenyl group), the PO molecular rotors consist of two rotators (a phenyl group and an alkoxy group), which exhibit simultaneous strongly electron-donating and easy rotational abilities. Compared with the control rotor PH, PO molecular rotors exhibited one order of magnitude higher quantum yield (fluorescence intensity) and simultaneously exhibited significantly higher fluorescence contrast. These properties are directly related to the strong electron-donating ability and low energy barrier of rotation of the alkoxy group, as confirmed by dynamic fluorescence experiments and quantum chemical calculations. The PO molecular rotors exhibited two fluorescence relaxation pathways, whereas the PH molecular rotor exhibited a single fluorescence relaxation pathway. Cellular fluorescence imaging with PO molecular rotors for mapping cellular viscosity was successfully demonstrated.

Pruritus occurs frequently in patients with polycythemia vera (PV), and the pathophysiology of PV-associated pruritus is unclear. We have previously demonstrated that transgenic mice expressing JAK2V617F displayed clear PV-like phenotypes. In the current study, we found frequent occurrence of pruritus with aged JAK2V617F transgenic mice and further investigated the underlying mechanisms by studying mast cells, key players in allergic reactions and anaphylaxis. Massive accumulations of mast cells were observed in the skin of pruritic JAK2V617F transgenic mice. In vitro culture yielded much higher mast cell counts from the bone marrow, spleen, peripheral blood, and peritoneal cavity of JAK2V617F transgenic mice than from controls. Cultured mast cells from JAK2V617F transgenic mice exhibited enhanced proliferative signals, relative resistance to cell death upon growth factor deprivation, and a growth advantage over control cells under suboptimal growth conditions. However, these mast cells displayed normal morphology and contained normal levels of mast cell proteases before and after degranulation. Finally, the JAK2 inhibitor G6 effectively reduced mast cell numbers and alleviated pruritus in JAK2V617F transgenic mice. Collectively, these data demonstrate that mast cells are involved in PV-associated pruritogenesis and that JAK2 inhibitors are potential antipruritus drugs.

The reversibility of lithium plating/stripping should be guaranteed in lithium metal batteries. Seriously polarized lithium growth during plating leads to the dendritic evolution of lithium metal due to the uneven current distribution on the electrically conductive surface. Artificial protective layers covering electrodes (e.g., polymer film on copper foil) have been used to narrow the gap of the current density between positions on the conductive surface. Herein, we incorporated an active ingredient to attract lithium ions into the dendrite-suppressing layer. Pyridinic nitrogen of graphitic carbon nitride (g-C3N4) served as the lithium ion affinity center. Conformation of the nitrogen was changed from pyridinic to graphitic in the presence of lithium ions, which confirms the coordination of lithium ion to the pyridinic nitrogen. Lithium metal was plated between the g-C3N4 layer and the copper current collector (or the lithium metal). The homogeneous lithium nucleation expected from the active role of the pyridinic nitrogen on regulating ionic pathways suppressed the dendritic growth of lithium metal and decreased the overpotential required for the initial metal nucleation. Due to the top-down ion flux regulation on the uppermost surface (or tip) of lithium metal, the reversibility of lithium plating/stripping was dramatically improved.

In this study, we analyzed the structure–activity relationship properties of the small molecule Jak2 inhibitor G6. We synthesized a set of derivatives containing the native para -hydroxyl structure or an alternative meta -hydroxyl structure and examined their Jak2 inhibitory properties. We found that the para-hydroxyl derivative known as NB15 had excellent Jak2 inhibitory properties in silico, in vitro, and ex vivo when compared with meta -hydroxyl derivatives. These results indicate that NB15 is a potent derivative of the Jak2 inhibitor G6, and that maintaining the para-hydroxyl orientation of G6 is critical for its Jak2 inhibitory potential.

Hyperkinetic Jak2 tyrosine kinase signaling has been implicated in several hematological disorders, including myeloproliferative neoplasms. Effective Jak2 inhibitors can have significant therapeutic potential. Here, using structure-based virtual screening, we identified a benzothiophene-derived Jak2 inhibitor named A46 . We hypothesized that this compound would inhibit Jak2-V617F–mediated pathologic cell growth. To test this, A46 was analyzed for its ability to inhibit recombinant Jak2 protein catalysis; suppress Jak2-mediated pathogenic cell growth in vitro; inhibit the aberrant ex vivo growth of Jak2-V617F–expressing primary human bone marrow cells; and inhibit Jak2-mediated pathogenesis in vivo. To this end, we found that A46 selectively inhibited Jak2-V617F protein when compared to wild-type Jak2 protein. The drug also selectively inhibited the proliferation of Jak2-V617F–expressing cells in both a time- and dose-dependent manner, and this correlated with decreased Jak2 and signal transducers and activators of transcription 5 phosphorylation within treated cells. The Jak2-V617F cell growth inhibition correlated with an induction of cell cycle arrest and promotion of apoptosis. A46 also inhibited the pathologic growth of primary Jak2-V617F–expressing bone marrow cells ex vivo. Lastly, using a mouse model of Jak2-V617F–mediated myeloproliferative neoplasia. A46 significantly reduced the splenomegaly and megakaryocytic hyperplasia in the spleens of treated mice and the levels of interleukin-6 in the plasma. Collectively, our data demonstrate that the benzothiophene-based compound, A46, suppresses Jak2-mediated pathogenesis, thereby making it a potential candidate drug against Jak2-mediated disorders.

Replacing noble-metal-based oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) electrocatalysts is the key to developing efficient Zn-air batteries (ZABs). Here, a homogeneous ternary Ni46 Co40 Fe14 nanoalloy with a size distribution of 30-60 nm dispersed in a carbon matrix (denoted as C@NCF-900) as a highly efficient bifunctional electrocatalyst produced via supercritical reaction and subsequent heat treatment at 900 °C is reported. Among all the transition-metal-based electrocatalysts, the C@NCF-900 exhibits the highest ORR performance in terms of half-wave potential (0.93 V) in 0.1 m KOH. Moreover, C@NCF-900 exhibits negligible activity decay after 10 000 voltage cycles with minor reduction (0.006 V). In ZABs, C@NCF-900 outperforms the mixture of Pt/C 20 wt% and IrO2 , cycled over 100 h under 58% depth of discharge condition. Furthermore, density functional theory (DFT) calculations and in situ X-ray absorption spectroscopy strongly support the active sites and site-selective reaction as a plausible ORR/OER mechanism of C@NCF-900.

We previously found that Jak2 kinase, expressed within vascular smooth muscle cells (VSMC), plays a critical role in angiotensin II (Ang II)-mediated hypertension. Given that Jak2 mediates both pressor-dependent and pressor-independent events, we sought to determine the role of blood pressure (BP), per se, on the deleterious effects of Jak2 within the kidney. To investigate this, three groups of mice were examined; i) wild type mice (Controls) that received Ang II infusion, ii) mice lacking Jak2 expression within the VSMC (VSMC Jak2 Null) that also received Ang II, and iii) Control mice that received Ang II plus an anti-hypertensive triple therapy (3Rx). After baseline BP recordings, Ang II was infused (1000 ng/kg/min, SC) to all groups and the 3Rx regimen (80 mg/L hydralazine, 5 mg/L reserpine, 30 mg/L hydrochlorothiazide in the drinking water) was initiated two days later to the 3Rx group, in order to maintain BP at similar levels to the VSMC Jak2 Null group. After 28 days of Ang II, mice were euthanized and the kidneys were assessed via histological, molecular, and functional approaches. Chronic Ang II infusion significantly increased the levels of intrarenal Ang II in all three groups; Control = 1,262±283 fmol/g, VSMC Jak2 Null = 1,655±666 fmol/g, and 3Rx = 2,174±588. While Ang II infusion significantly increased the mean BP in the Control group (152 ± 2 mm Hg), it was significantly, and similarly, lower in both the VSMC Jak2 Null and 3Rx groups (125 ± 5 mm Hg and 131 ± 5 mm Hg, respectively). Glomerular sclerosis was absent and interstitial fibrosis ranged from absent- mild- moderate, and was similar in all groups. The increases in i) perivascular infiltration of CD3+ lymphocytes, ii) CTGF gene expression, iii) tubule casts and iv) albuminuria that were observed in the Control mice, were significantly reduced in both the VSMC Jak2 Null and 3Rx groups. [CTGF mRNA Levels: Control = 100%±17, VSMC Jak2 Null = 70%±12*, 3Rx= 56%±17*. Urine Albumin (ng/day): Control = 414 ± 262, VSMC Jak2 Null = 138 ± 172*, 3Rx= 101 ± 89* (*, p

Glioblastoma multiforme (GBM) is the most common and the most aggressive form of primary brain tumor. Jak2 is a non-receptor tyrosine kinase that is involved in proliferative signaling through its association with various cell surface receptors. Hyperactive Jak2 signaling has been implicated in numerous hematological disorders as well as in various solid tumors including GBM. Our lab has developed a Jak2 small molecule inhibitor known as G6. It exhibits potent efficacy in vitro and in several in vivo models of Jak2-mediated hematological disease. Here, we hypothesized that G6 would inhibit the pathogenic growth of GBM cells expressing hyperactive Jak2. To test this, we screened several GBM cell lines and found that T98G cells express readily detectable levels of active Jak2. We found that G6 treatment of these cells reduced the phosphorylation of Jak2 and STAT3, in a dose-dependent manner. In addition, G6 treatment reduced the migratory potential, invasive potential, clonogenic growth potential, and overall viability of these cells. The effect of G6 was due to its direct suppression of Jak2 function and not via off-target kinases, as these effects were recapitulated in T98G cells that received Jak2 specific shRNA. G6 also significantly increased the levels of caspase-dependent apoptosis in T98G cells, when compared to cells that were treated with vehicle control. Lastly, when T98G cells were injected into nude mice, G6 treatment significantly reduced tumor volume and this was concomitant with significantly decreased levels of phospho-Jak2 and phospho-STAT3 within the tumors themselves. Furthermore, tumors harvested from mice that received G6 had significantly less vimentin protein levels when compared to tumors from mice that received vehicle control solution. Overall, these combined in vitro and in vivo results indicate that G6 may be a viable therapeutic option against GBM exhibiting hyperactivation of Jak2.

Germline deletion of Jak2 in mice results in embryonic lethality at E12.5 due to impaired hematopoiesis. However, the role that Jak2 might play in late gestation and postnatal life is unknown. To understand this, we utilized a conditional knockout approach that allowed for the deletion of Jak2 at various stages of prenatal and postnatal life. Specifically, Jak2 was deleted beginning at either mid/late gestation (E12.5), at postnatal day 4 (PN4), or at ∼2 months of age. Deletion of Jak2 beginning at E12.5 resulted in embryonic death characterized by a lack of hematopoiesis. Deletion beginning at PN4 was also lethal due to a lack of erythropoiesis. Deletion of Jak2 in young adults was characterized by blood cytopenias, abnormal erythrocyte morphology, decreased marrow hematopoietic potential, and splenic atrophy. However, death was observed in only 20% of the mutants. Further analysis of these mice suggested that the increased survivability was due to an incomplete deletion of Jak2 and subsequent re-population of Jak2 expressing cells, as conditional deletion in mice having one floxed Jak2 allele and one null allele resulted in a more severe phenotype and subsequent death of all animals. We found that the deletion of Jak2 in the young adults had a differential effect on hematopoietic lineages; specifically, conditional Jak2 deletion in young adults severely impaired erythropoiesis and thrombopoiesis, modestly affected granulopoiesis and monocytopoiesis, and had no effect on lymphopoiesis. Interestingly, while the hematopoietic organs of these mutant animals were severely affected by the deletion of Jak2, we found that the hearts, kidneys, lungs, and brains of these same mice were histologically normal. From this, we conclude that Jak2 plays an essential and non-redundant role in hematopoiesis during both prenatal and postnatal life and this has direct implications regarding the inhibition of Jak2 in humans.

We recently developed a Janus kinase 2 (Jak2) small-molecule inhibitor called G6 and found that it inhibits Jak2-V617F– mediated pathologic cell growth in vitro, ex vivo, and in vivo. However, its ability to inhibit Jak2-V617F–mediated myeloproliferative neoplasia, with particular emphasis in the bone marrow, has not previously been examined. Here, we investigated the efficacy of G6 in a transgenic mouse model of Jak2-V617F–mediated myeloproliferative neoplasia. We found that G6 provided therapeutic benefit to the peripheral blood as determined by elimination of leukocytosis, thrombocytosis, and erythrocytosis. G6 normalized the pathologically high plasma concentrations of interleukin 6 (IL-6). In the liver, G6 eliminated Jak2-V617F–driven extramedullary hematopoiesis. With respect to the spleen, G6 significantly reduced both the spleno-megaly and megakaryocytic hyperplasia. In the critically important bone marrow, G6 normalized the pathologically high levels of phospho-Jak2 and phospho–signal transducer and activator of transcription 5 (STAT5). It significantly reduced the megakaryocytic hyperplasia in the marrow and completely normalized the M/E ratio. Most importantly, G6 selectively reduced the mutant Jak2 burden by 67% on average, with virtual elimination of mutant Jak2 cells in one third of all treated mice. Lastly, clonogenic assays using marrow stem cells from the myeloproliferative neoplasm mice revealed a time-dependent elimination of the clonogenic growth potential of these cells by G6. Collectively, these data indicate that G6 exhibits exceptional efficacy in the peripheral blood, liver, spleen, and, most importantly, in the bone marrow, thereby raising the possibility that this compound may alter the natural history of Jak2-V617F–mediated myeloproliferative neoplasia.

Previous analyses of tso1 mutants revealed a loss of control of directional cellular expansion and coordination of growth of adjacent cells, and defects in karyokinesis and cytokinesis. We isolated TSO1 using a map-based approach, and show that it is a member of a family of at least three genes in Arabidopsis. Consistent with the mutant phenotype, TSO1 transcript was most abundant in flowers, where it accumulated to the highest levels in developing ovules and microspores. The putative TSO1 protein has two cysteine-rich regions that are similar to the CXC domains of a variety of proteins from plants and animals, including a class of kinesins involved in chromosome segregation, and enhancer of zeste-type proteins. Visualization of TSO1-fusion proteins indicated that TSO1 is a nuclear protein. The tso1 mutant phenotypes and the novelty of the TSO1 sequence suggest the existence of previously unknown participants in regulation of directional processes in eukaryotic cells.

Philadelphia chromosome–negative myeloproliferative neoplasms, including polycythemia vera, essential thrombocytosis, and myelofibrosis, are disorders characterized by abnormal hematopoiesis. Among these myeloproliferative neoplasms, myelofibrosis has the most unfavorable prognosis. Furthermore, currently available therapies for myelofibrosis have little to no efficacy in the bone marrow and hence, are palliative. We recently developed a Janus kinase 2 (Jak2) small molecule inhibitor called G6 and found that it exhibits marked efficacy in a xenograft model of Jak2-V617F–mediated hyperplasia and a transgenic mouse model of Jak2-V617F–mediated polycythemia vera/essential thrombocytosis. However, its efficacy in Jak2-mediated myelofibrosis has not previously been examined. Here, we hypothesized that G6 would be efficacious in Jak2-V617F–mediated myelofibrosis. To test this, mice expressing the human Jak2-V617F cDNA under the control of the vav promoter were administered G6 or vehicle control solution, and efficacy was determined by measuring parameters within the peripheral blood, liver, spleen, and bone marrow. We found that G6 significantly reduced extramedullary hematopoiesis in the liver and splenomegaly. In the bone marrow, G6 significantly reduced pathogenic Jak/STAT signaling by 53%, megakaryocytic hyperplasia by 70%, and the Jak2 mutant burden by 68%. Furthermore, G6 significantly improved the myeloid to erythroid ratio and significantly reversed the myelofibrosis. Collectively, these results indicate that G6 is efficacious in Jak2-V617F–mediated myelofibrosis, and given its bone marrow efficacy, it may alter the natural history of this disease.

Large-scale growth of high-quality hexagonal boron nitride has been a challenge in two-dimensional-material-based electronics. Herein, we present wafer-scale and wrinkle-free epitaxial growth of multilayer hexagonal boron nitride on a sapphire substrate by using high-temperature and low-pressure chemical vapor deposition. Microscopic and spectroscopic investigations and theoretical calculations reveal that synthesized hexagonal boron nitride has a single rotational orientation with AA' stacking order. A facile method for transferring hexagonal boron nitride onto other target substrates was developed, which provides the opportunity for using hexagonal boron nitride as a substrate in practical electronic circuits. A graphene field effect transistor fabricated on our hexagonal boron nitride sheets shows clear quantum oscillation and highly improved carrier mobility because the ultraflatness of the hexagonal boron nitride surface can reduce the substrate-induced degradation of the carrier mobility of two-dimensional materials.