The large‐scale production of metal–air batteries, an appealing solution for next‐generation energy storage, requires low‐cost, earth‐abundant, and efficient oxygen electrode materials, yet insights ...into active catalyst structures and synergistic reactivity remain largely unknown. Here, a new bifunctional oxygen electrode based on nitrogen‐doped carbon nanotubes decorated by spinel CuCo2O4 quantum dots (CuCo2O4/N‐CNTs) is reported, outperforming the benchmark of state‐of‐the‐art noble metal catalysts. Combining spectroscopic characterization and electrochemical studies, a prominent synergetic effect between CuCo2O4 and N‐doped carbon nanotubes is uncovered: the high conductivity, large active surface area, and increase in the number of catalytic sites induced by Cu doping (i.e., Cu2+ and CuN) can be beneficial to the overall electrocatalytic activities. Remarkably, the native flexibility of CuCo2O4/N‐CNTs allows its direct use as reversible oxygen electrodes in Zn–air batteries either with liquid alkaline electrolyte or in the all‐solid‐state configuration. The prepared devices demonstrate excellent discharging/charging performance, large energy density (83.83 mW cm−2 in liquid state, 1.86 W g−1 in all‐solid‐state), and long lifetime (48 h in liquid state, 9 h in all‐solid‐state), holding great promise in the practical application of rechargeable metal–air batteries and other fuel cells.
Advanced Cu Co bimetallic oxide quantum dots are decorated on nitrogen‐doped carbon nanotubes to serve as the bifunctional oxygen catalyst. A strong synergetic coupling in CuCo2O4/N‐CNTs is proposed, which provides advantaged local chemical environment and enriched catalytic sites. Benefiting from these features, CuCo2O4/N‐CNTs with reversible oxygen catalytic activity is capable of operating the new‐generation rechargeable zinc–air batteries.
Rational design and exploration of robust and low‐cost bifunctional oxygen reduction/evolution electrocatalysts are greatly desired for metal–air batteries. Herein, a novel high‐performance oxygen ...electrode catalyst is developed based on bimetal FeCo nanoparticles encapsulated in in situ grown nitrogen‐doped graphitic carbon nanotubes with bamboo‐like structure. The obtained catalyst exhibits a positive half‐wave potential of 0.92 V (vs the reversible hydrogen electrode, RHE) for oxygen reduction reaction, and a low operating potential of 1.73 V to achieve a 10 mA cm−2 current density for oxygen evolution reaction. The reversible oxygen electrode index is 0.81 V, surpassing that of most highly active bifunctional catalysts reported to date. By combining experimental and simulation studies, a strong synergetic coupling between FeCo alloy and N‐doped carbon nanotubes is proposed in producing a favorable local coordination environment and electronic structure, which affords the pyridinic N‐rich catalyst surface promoting the reversible oxygen reactions. Impressively, the assembled zinc–air batteries using liquid electrolytes and the all‐solid‐state batteries with the synthesized bifunctional catalyst as the air electrode demonstrate superior charging–discharging performance, long lifetime, and high flexibility, holding great potential in practical implementation of new‐generation powerful rechargeable batteries with portable or even wearable characteristic.
Bamboo‐like FeCo alloy encapsulated in nitrogen‐doped carbon nanotubes exhibits superior catalytic oxygen reduction and oxygen evolution performance than that of noble metal benchmarks, which benefits from the nitrogen‐rich and defect‐rich catalyst surface. The all‐solid‐state zinc–air batteries equipped by the synthesized materials show low charging/discharging overpotentials, long lifetime, and high flexibility, suitable for practical application.
Tunability and stability in the electrical properties of 2D semiconductors pave the way for their practical applications in logic devices. A robust layered indium selenide (InSe) field‐effect ...transistor (FET) with superior controlled stability is demonstrated by depositing an indium (In) doping layer. The optimized InSe FETs deliver an unprecedented high electron mobility up to 3700 cm2 V−1 s−1 at room temperature, which can be retained with 60% after 1 month. Further insight into the evolution of the position of the Fermi level and the microscopic device structure with different In thicknesses demonstrates an enhanced electron‐doping behavior at the In/InSe interface. Furthermore, the contact resistance is also improved through the In insertion between InSe and Au electrodes, which coincides with the analysis of the low‐frequency noise. The carrier fluctuation is attributed to the dominance of the phonon scattering events, which agrees with the observation of the temperature‐dependent mobility. Finally, the flexible functionalities of the logic‐circuit applications, for instance, inverter and not‐and (NAND)/not‐or (NOR) gates, are determined with these surface‐doping InSe FETs, which establish a paradigm for 2D‐based materials to overcome the bottleneck in the development of electronic devices.
A robust layered indium selenide (InSe) field‐effect transistor (FET) with superior high mobility (3700 cm2 V−1 s−1 at room temperature) is demonstrated by depositing an indium doping layer. With tunable carrier transport, the surface‐doped InSe FETs present flexible operations to realize various logic circuits, such as inverters and not‐or and not‐and gates.
We perform a comprehensive analysis of the homogeneous finite modular group Γ′4 ≡ S′4, which is the double covering of S4 group. The weight 1 modular forms of level 4 are constructed in terms of the ...Dedekind eta function, and they transform as a triplet ^3′ of S′4. The integral weight modular forms until weight 6 are built from the tensor products of weight 1 modular forms. We perform a systematical classification of S′4 modular models for lepton masses and mixing with and without generalized CP, where the left-handed leptons are assigned to a triplet of S′4 and right-handed charged leptons transform as singlets under S′4, and we consider both scenarios where the neutrino masses arise from a Weinberg operator or type-I seesaw mechanism. The phenomenological implications of the minimal models for lepton masses, mixing angles, CP violation phases, and neutrinoless double decay are discussed. The S′4 modular symmetry is extended to the quark sector, and we present several predictive models which use nine or ten free parameters including real and imaginary parts of τ to describe quark masses and the Cabibbo-Kobayashi-Maskawa mixing matrix. We give a quark-lepton unified model which can explain the flavor structure of quarks and leptons simultaneously for a common value of τ.
We generalize the modular invariance approach to include the half-integral weight modular forms. Accordingly the modular group should be extended to its metaplectic covering group for consistency. We ...introduce the well-defined half-integral weight modular forms for congruence subgroup Γ(4N) and show that they can be decomposed into the irreducible multiplets of finite metaplectic groupΓ4N. We construct concrete expressions of the half-integral/integral modular forms for Γ (4) up to weight 6 and arrange them into the irreducible multiplets of Γ4. We present three typical models with Γ4 modular symmetry for neutrino masses and mixing, and the phenomenological predictions of each model are analyzed numerically.
We perform a comprehensive study of the homogeneous finite modular group A′5 which is the double covering of A5. The integral weight and level 5 modular forms have been constructed up to weight 6 and ...they are decomposed into the irreducible representations of A′5. Then we perform a systematical analysis of the A′5 modular models for lepton masses and mixing. The phenomenologically viable models with minimal number of free parameters and the results of fit are presented. We find out 15 models with 9 real free parameters which can accommodate the experimental data of lepton sector. After including generalized C P symmetry, 9 viable models with 7 free parameters are found out. We apply A′5 modular symmetry to the quark sector, and a quark-lepton unification model is given. The framework of modular invariance is extended to include the rational weight modular forms of level 5. The ring of modular forms at level 5 can be generated by two algebraically independent weight 1 / 5 modular forms denoted by F1(τ) and F2(τ) . We give the expressions of the rational weight modular forms of level 5 up to weight 3 and arrange them into the irreducible multiplets of finite metaplectic group ˜Γ5 ≅ A′5 × Z5. A neutrino mass model with ˜Γ5 modular symmetry is presented, and the phenomenological predictions of the model are analyzed numerically.
Sustained energy starvation leads to activation of AMP-activated protein kinase (AMPK), which coordinates energy status with numerous cellular processes including metabolism, protein synthesis, and ...autophagy. Here, we report that AMPK phosphorylates the histone methyltransferase EZH2 at T311 to disrupt the interaction between EZH2 and SUZ12, another core component of the polycomb repressive complex 2 (PRC2), leading to attenuated PRC2-dependent methylation of histone H3 at Lys27. As such, PRC2 target genes, many of which are known tumor suppressors, were upregulated upon T311-EZH2 phosphorylation, which suppressed tumor cell growth both in cell culture and mouse xenografts. Pathologically, immunohistochemical analyses uncovered a positive correlation between AMPK activity and pT311-EZH2, and higher pT311-EZH2 correlates with better survival in both ovarian and breast cancer patients. Our finding suggests that AMPK agonists might be promising sensitizers for EZH2-targeting cancer therapies.
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•AMPK activation attenuates PRC2-mediated epigenetic silencing•AMPK phosphorylates EZH2 at T311 to disrupt EZH2-SUZ12 interaction•EZH2 T311 phosphorylation inhibits PRC2 oncogenic function•EZH2 T311 phosphorylation correlates with better survival in cancer patients
The metabolic state of the cell can be connected to gene expression and modification of histones through several mechanisms. Wan et al. find that AMPK-mediated phosphorylation of EZH2 at T311 inhibits PRC2 methyltransferase activity to relieve PRC2-dependent epigenetic silencing and subsequently suppresses tumorigenesis.
The continued threat of emerging, highly lethal infectious pathogens such as Middle East respiratory syndrome coronavirus (MERS‐CoV) calls for the development of novel vaccine technology that offers ...safe and effective prophylactic measures. Here, a novel nanoparticle vaccine is developed to deliver subunit viral antigens and STING agonists in a virus‐like fashion. STING agonists are first encapsulated into capsid‐like hollow polymeric nanoparticles, which show multiple favorable attributes, including a pH‐responsive release profile, prominent local immune activation, and reduced systemic reactogenicity. Upon subsequent antigen conjugation, the nanoparticles carry morphological semblance to native virions and facilitate codelivery of antigens and STING agonists to draining lymph nodes and immune cells for immune potentiation. Nanoparticle vaccine effectiveness is supported by the elicitation of potent neutralization antibody and antigen‐specific T cell responses in mice immunized with a MERS‐CoV nanoparticle vaccine candidate. Using a MERS‐CoV‐permissive transgenic mouse model, it is shown that mice immunized with this nanoparticle‐based MERS‐CoV vaccine are protected against a lethal challenge of MERS‐CoV without triggering undesirable eosinophilic immunopathology. Together, the biocompatible hollow nanoparticle described herein provides an excellent strategy for delivering both subunit vaccine candidates and novel adjuvants, enabling accelerated development of effective and safe vaccines against emerging viral pathogens.
To improve vaccination efforts against Middle East respiratory syndrome coronavirus (MERS‐CoV), a virus‐mimicking vaccine is herein prepared with a capsid‐like hollow polymeric nanoparticle loaded with STING agonists and coated in MERS‐CoV antigens. The viromimetic nanoparticle facilitates safe and effective vaccination against the lethal virus and offers a versatile platform for combatting emerging infectious threats.
The emergence of severe acute respiratory syndrome coronavirus‐2 (SARS‐CoV‐2) variants has altered the trajectory of the COVID‐19 pandemic and raised some uncertainty on the long‐term efficiency of ...vaccine strategy. The development of new therapeutics against a wide range of SARS‐CoV‐2 variants is imperative. We, here, have designed an inhalable siRNA, C6G25S, which covers 99.8% of current SARS‐CoV‐2 variants and is capable of inhibiting dominant strains, including Alpha, Delta, Gamma, and Epsilon, at picomolar ranges of IC50 in vitro. Moreover, C6G25S could completely inhibit the production of infectious virions in lungs by prophylactic treatment, and decrease 96.2% of virions by cotreatment in K18‐hACE2‐transgenic mice, accompanied by a significant prevention of virus‐associated extensive pulmonary alveolar damage, vascular thrombi, and immune cell infiltrations. Our data suggest that C6G25S provides an alternative and effective approach to combating the COVID‐19 pandemic.
Synopsis
C6G25S is a fully modified siRNA specifically targeting the highly‐conserve region of SARS‐CoV‐2 genome. It has been developed as an inhalable and broad‐spectrum therapeutic that is highly stable and effective via direct respiratory administration.
A broadly active siRNA covers 99.8% of SARS‐CoV‐2 variants, including highly infective Delta and Omicron.
C6G25S completely inhibited the Delta variant in lungs of infected mice by prophylactic treatment and decreased 93% of virions by co‐treatment.
First study that use fully modified siRNA for inhalation and achieved promising therapeutic effect without a special delivery system.
C6G25S is a safe, effective, and feasible therapeutic approach that could reach the market in a short time.
C6G25S is a fully modified siRNA specifically targeting the highly‐conserve region of SARS‐CoV‐2 genome. It has been developed as an inhalable and broad‐spectrum therapeutic that is highly stable and effective via direct respiratory administration.
A minimal modular invariant neutrino model Ding, Gui-Jun; Liu, Xiang-Gan; Yao, Chang-Yuan
The journal of high energy physics,
01/2023, Letnik:
2023, Številka:
1
Journal Article
Recenzirano
Odprti dostop
A
bstract
We present a neutrino mass model based on modular symmetry with the fewest input parameters to date, which successfully accounts for the 12 lepton masses and mixing parameters through 6 ...real free parameters including the modulus. The neutrino masses are predicted to be normal ordering, the atmospheric angle
θ
23
is quite close to maximal value and the Dirac CP phase
δ
CP
is about 1
.
34
π
. We also study the soft supersymmetry breaking terms due to the modulus
F
-term in this minimal model, which are constrained to be the non-holomorphic modular forms. The radiative lepton flavor violation process
μ → eγ
is discussed.
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