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Bone marrow stem cells (BMSCs) are multipotent stem cells that can regenerate mesenchymal tissues, such as adipose tissue, bone, and muscle. Recent studies have shown that N6-methyladenosine (m6A) methylation, one of the most prevalent epigenetic modifications, is involved in the development process. However, whether it plays roles in BMSC differentiation is still elusive. Here, we found that the deletion of m6A "writer" protein methyltransferase-like (METTL)3 in porcine BMSCs (pBMSCs) could promote adipogenesis and janus kinase (JAK)1 protein expression via an m6A-dependent way. Knockdown of METTL3 decreased mRNA m6A levels of JAK1, leading to enhanced YTH m6A RNA binding protein 2 (YTHDF2)-dependent JAK1 mRNA stability. We further demonstrated that JAK1 activated signal transducer and activator of transcription (STAT) 5 through regulation of its phosphorylation to bind to the promoter of CCAAT/enhancer binding protein (C/EBP) β, which could ultimately lead to a modulated adipogenic process. Collectively, our results reveal an orchestrated network linking the m6A methylation and JAK1/STAT5/C/EBPβ pathway in pBMSCs adipogenic differentiation. Our findings provide novel insights into the underlying molecular mechanisms of m6A modification in the regulation of BMSCs differentiating into adipocytes, which may pave a way to develop more effective therapeutic strategies in stem cell regenerative medicine and the treatment of obesity. [ABSTRACT FROM AUTHOR]

In this study, ternary Cu2SnS3 (CTS) nanostructure materials with high crystallinity were successfully prepared via a facile solvothermal method, which was followed by high-temperature treatment. The morphology of the as-synthesized samples is uniform flower-like spheres, with these spheres consisting of hierarchical nanosheets and possessing network features. Sodium storage measurements demonstrate that the annealed CTS electrodes have high initial reversible capacity (447.7 mAh.1 at a current density of 100 mA.1), good capacity retention (200.6 mAh.1 after 50 cycles at a current density of 100 mA.1) and considerable rate capability because of their high crystallinity and unique morphology. Such good performances indicate that the high crystallinity CTS is a promising anode material for sodium ion batteries. [ABSTRACT FROM AUTHOR]

We construct a series of bbosonic-symmetry-protected topological (BSPT) states beyond group cohomology classification using "decorated defects" approach. This construction is based on topological defects of ordinary Landau order parameters, decorated with the bosonic short-range entangled (BSRE) states in (4k + 3)d and (4k + 5)d space-time (with k being nonnegative integers), which do not need any symmetry. This approach not only gives these BSPT states an intuitive physical picture, it also allows us to derive the effective field theory for all these BSPT states beyond group cohomology. [ABSTRACT FROM AUTHOR]

In this paper we systematically classify and describe bosonic symmetry protected topological (SPT) phases in all physical spatial dimensions using semiclassical nonlinear Sigma model (NLSM) field theories. All the SPT phases on a d-dimensional lattice discussed in this paper can be described by the same NLSM, which is an O(d+2) NLSM in (d+1)-dimensional space-time, with a topological Θ-term. The field in the NLSM is a semiclassical Landau order parameter with a unit length constraint. The classification of SPT phases discussed in this paper based on their NLSMs is Completely Identical to the more mathematical classification based on group cohomology. Besides the classification, the formalism used in this paper also allows us to explicitly discuss the physics at the boundary of the SPT phases, and it reveals the relation between SPT phases with different symmetries. For example, it gives many of these SPT states a natural "decorated defect" construction. [ABSTRACT FROM AUTHOR]

We demonstrate that the anyon statistics and three-loop statistics of various 2d and 3d topological phases can be derived using semiclassical nonlinear sigma model field theories with a topological Θ term. In our formalism, the braiding statistics has a natural geometric meaning; The braiding process of anyons or loops leads to a nontrivial field configuration in the space-time, which will contribute a braiding phase factor due to the Θ term. [ABSTRACT FROM AUTHOR]

We demonstrate the following conclusion: If ∣Ψ> is a one-dimensional (ID) or two-dimensional (2D) nontrivial short-range entangled state and ∣Q> is a trivial disordered state defined on the same Hilbert space, then the following quantity (so-called "strange correlator") C(r, r') = (Ω∣ϕ(r)ϕ(r')∣Ψ)/<Ω∣Ψ> either saturates to a constant or decays as a power law in the limit ∣r - r'l →+∞, even though both ∣Ω) and IΨ) are quantum disordered states with short-range correlation; ϕ(r) is some local operator in the Hilbert space. This result is obtained based on both field theory analysis and an explicit computation of C(r, r') for four different examples: ID Haldane phase of spin-1 chain, 2D quantum spin Hall insulator with a strong Rashba spin-orbit coupling, 2D spin-2 Affleck-Kennedy-Lieb-Tasaki state on the square lattice, and the 2D bosonic symmetry-protected topological phase with Z2 symmetry. This result can be used as a diagnosis for short-range entangled states in ID and 2D. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) symmetry-protected topological (SPT) phase by definition must have symmetryprotected nontrivial boundary states; namely, its two-dimensional (2D) boundary must be either gapless or degenerate. In this work we demonstrate that once we couple a 3D SPT phase to a lattice dynamical Z2 gauge field, in many cases the Z2 vison line excitation (line defect) can be viewed as a 'one-dimensional (ID) boundary" of the 3D SPT phase, and this line defect is guaranteed to have a gapless or degenerate spectrum, which is also protected by the symmetry of the SPT phase. [ABSTRACT FROM AUTHOR]

Abstract: ZnO complex 3D nano-structures have been self-organized on Al2O3 (0001) substrate by laser molecular beam epitaxy (L-MBE). It is shown by AFM morphology that the structure is composed of 1D quantum dot chains (QDCs) and larger nano-islands at the nodes of QDCs. The formation mechanism of the nano-structure is also investigated. XRD results indicate that the nano-structure is highly c-axis oriented, with the aligned in-plane oriented domains. Time-integrated photoluminescence (TIPL) of the sample shows obvious blue-shift and broadening of the near band-edge (NBE) emission at room temperature, which are related to the quantum confinement effects. Time-resolved PL (TRPL) result shows bi-exponential decay behavior of ZnO QDCs, with a fast decay time of 38.21ps and a low decay time of 138.19ps, respectively, which is considered to be originated from the interdot coupling made by coherent emission and reabsorption of the photons in QDCs. [Copyright &y& Elsevier]

We investigate the moiré band structures and the strong correlation effects in twisted bilayer MoTe2 for a wide range of twist angles, employing a combination of various techniques. Using large-scale first-principles calculations, we pinpoint realistic continuum modeling parameters, subsequently deriving the maximally localized Wannier functions for the top three moiré bands. Simplifying our model with reasonable assumptions, we obtain a minimal two-band model, encompassing Coulomb repulsion, correlated hopping, and spin exchange. Our minimal interaction models pave the way for further exploration of the rich many-body physics in twisted MoTe2. Furthermore, we explore the phase diagrams of the system through Hartree-Fock approximation and exact diagonalization (ED). Our two-band ED analysis underscores significant band-mixing effects in this system, which enlarge the optimal twist angle for fractional quantum anomalous Hall states. [ABSTRACT FROM AUTHOR]

We propose a d-dimensional interacting Majorana fermion model with quenched disorder, which gives us a continuous quantum phase transition between a diffusive thermal metal phase with a finite entropy density to an insulator phase with zero entropy density. This model is based on coupled Sachdev-Ye-Kitaev model clusters, and hence has a controlled large-N limit. The metal-insulator transition is accompanied by a spontaneous time-reversal symmetry breaking. We perform controlled calculations to show that the energy diffusion constant jumps to zero discontinuously at the metal-insulator transition, while the time-reversal symmetry-breaking order parameter increases continuously. [ABSTRACT FROM AUTHOR]

We show that the out-of-time-order correlation (OTOC) 〈W(t)†V(0)†W(t)V(0)〉 in many-body localized (MBL) and marginal MBL systems can be efficiently calculated by the spectrum bifurcation renormalization group (SBRG). We find that in marginal MBL systems, the scrambling time tscr follows a stretched exponential scaling with the distance d WV between the operators W and V : tscr ~ exp (√dWV/l0), which demonstrates Sinai diffusion of quantum information and the enhanced scrambling by the quantum criticality in nonchaotic systems. [ABSTRACT FROM AUTHOR]

Bosonic symmetry protected topological (BSPT) states, the bosonic analogue of topological insulators, have attracted enormous theoretical interest in the last few years. Although BSPT states have been classified by various approaches, there is so far no successful experimental realization of any BSPT state in two or higher dimensions. In this paper, we propose that a two-dimensional BSPT state with U(1)×U(1) symmetry can be realized in bilayer graphene in a magnetic field. Here the two U(1) symmetries represent total spin Sz and total charge conservation, respectively. The Coulomb interaction plays a central role in this proposal--it gaps out all the fermions at the boundary, so that only bosonic charge and spin degrees of freedom are gapless and protected at the edge. Based on the above conclusion, we propose that the bulk quantum phase transition between the BSPT and trivial phase, which can be driven by applying both magnetic and electric fields, can become a "bosonic phase transition" with interactions. That is, only bosonic modes close their gap at the transition, which is fundamentally different from all the well-known topological insulator to trivial insulator transitions that occur for free fermion systems. We discuss various experimental consequences of this proposal. [ABSTRACT FROM AUTHOR]

In the last few years a lot of exotic and anomalous topological phases were constructed by proliferating the vortexlike topological defects on the surface of the 3d topological insulator (TI) [Fidkowski et al., Phys. Rev. X 3, 041016 (2013); Chen et al., Phys. Rev. B 89, 165132 (2014); Bonderson et al., J. Stat. Mech. (2013) P09016; Wang et al., Phys. Rev. B 88, 115137 (2013); Metlitski et al., Phys. Rev. B 92, 125111 (2015)]. In this work, rather than considering topological phases at the boundary, we will study quantum critical points driven by vortexlike topological defects. In general, we will discuss a (2+1)d quantum phase transition described by the following field theory: L=ψ¯¯γμ(∂μ-iaμ)ψ+|(∂μ-ikaμ)ϕ|²+r|ϕ|²+g|ϕ|4, with tuning parameter r, arbitrary integer k, Dirac fermion ψ, and complex scalar bosonic field ϕ, which both couple to the same (2+1)d dynamical noncompact U(1) gauge field aμ. The physical meaning of these quantities/fields will be explained in the text. Making use of the new duality formalism developed in [Metlitski et al., Phys. Rev. B 93, 245151 (2016); Wang et al., Phys. Rev. X 5, 041031 (2015); Wang et al., Phys. Rev. B 93, 085110 (2016); D. T. Son, Phys. Rev. X 5, 031027 (2015)], we demonstrate that this quantum critical point has a quasi-self-dual nature. And at this quantum critical point, various universal quantities such as the electrical conductivity and scaling dimension of gauge-invariant operators, can be calculated systematically through a 1/k² expansion, based on the observation that the limit k→+∞ corresponds to an ordinary 3d XY transition. [ABSTRACT FROM AUTHOR]

We propose a series of simple two-dimensional (2D) lattice interacting fermion models that we demonstrate at low energy describe bosonic symmetry-protected topological (SPT) states and quantum phase transitions between them. This is because due to interaction, the fermions are gapped both at the boundary of the SPT states and at the bulk quantum phase transition, thus these models at low energy can be described completely by bosonic degrees of freedom. We show that the bulk of these models is described by a Sp(N) principal chiral model with a topological T term, whose boundary is described by a Sp(N) principal chiral model with a Wess-Zumino-Witten term at level 1. The quantum phase transition between SPT states in the bulk is tuned by a particular interaction term, which corresponds to tuning T in the field theory, and the phase transition occurs at Θ=π. The simplest version of these models with N=1 is equivalent to the familiar O(4) nonlinear sigma model (NLSM) with a topological term, whose boundary is a (1+1)D conformal field theory with central charge c=1. After breaking the O(4) symmetry to its subgroups, this model can be viewed as bosonic SPT states with U(1), or Z2 symmetries, etc. All of these fermion models, including the bulk quantum phase transitions, can be simulated with the determinant quantum Monte Carlo method without the sign problem. Recent numerical results strongly suggest that the quantum disordered phase of the O(4) NLSM with precisely Θ=π is a stable (2+1)D conformal field theory with gapless bosonic modes. [ABSTRACT FROM AUTHOR]

The plastidic 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway is one of the most important pathways in plants and produces a large variety of essential isoprenoids. Its regulation, however, is still not well understood. Using the stable isotope 13C-labeling technique, we analyzed the carbon fluxes through the MEP pathway and into the major plastidic isoprenoid products in isoprene-emitting and transgenic isoprene-nonemitting (NE) gray poplar (Populus x canescens). We assessed the dependence on temperature, light intensity, and atmospheric [CO2]. Isoprene biosynthesis was by far (99%) the main carbon sink of MEP pathway intermediates in mature gray poplar leaves, and its production required several fold higher carbon fluxes compared with NE leaves with almost zero isoprene emission. To compensate for the much lower demand for carbon, NE leaves drastically reduced the overall carbon flux within the MEP pathway. Feedback inhibition of 1-deoxy-D-xylulose-5-phosphate synthase activity by accumulated plastidic dimethylallyl diphosphate almost completely explained this reduction in carbon flux. Our data demonstrate that short-term biochemical feedback regulation of 1-deoxy-D-xylulose-5-phosphate synthase activity by plastidic dimethylallyl diphosphate is an important regulatory mechanism of the MEP pathway. Despite being relieved from the large carbon demand of isoprene biosynthesis, NE plants redirected only approximately 0.5% of this saved carbon toward essential nonvolatile isoprenoids, i.e. β-carotene and lutein, most probably to compensate for the absence of isoprene and its antioxidant properties. [ABSTRACT FROM AUTHOR]

ZnO thin films were grown on SiO2/Si substrates by radio-frequency magnetron sputtering. Based on the ZnO film, a photoconductive metal-semiconductor-metal ultraviolet detector was fabricated by a liftoff technique. Its I-V characteristics were observed at 365 nm, and a fast response was observed by illumination with a KrF excimer laser. [ABSTRACT FROM AUTHOR]