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Vector models and generalized SYK models

We consider the relation between SYK-like models and vector models by studying a toy model where a tensor field is coupled with a vector field. By integrating out the tensor field, the toy model reduces to the Gross-Neveu model in 1 dimension. On the other hand, a certain perturbation can be turned on and the toy model flows to an SYK-like model at low energy. A chaotic...

Correlators in the \( \mathcal{N}=2 \) supersymmetric SYK model

We study correlation functions in the one-dimensional \( \mathcal{N}=2 \) supersymmetric SYK model. The leading order 4-point correlation functions are computed by summing over ladder diagrams expanded in a suitable basis of conformal eigenfunctions. A novelty of the \( \mathcal{N}=2 \) model is that both symmetric and antisymmetric eigenfunctions are required. Although we use a...

A supersymmetric SYK-like tensor model

We consider a supersymmetric SYK-like model without quenched disorder that is built by coupling two kinds of fermionic \( \mathcal{N}=1 \) tensor-valued superfields, “quarks” and “mesons”. We prove that the model has a well-defined large-N limit in which the (s)quark 2-point functions are dominated by mesonic “melon” diagrams. We sum these diagrams to obtain the Schwinger-Dyson...

Higher spins and Yangian symmetries

The relation between the bosonic higher spin \( {\mathcal{W}}_{\infty}\left[\lambda \right] \) algebra, the affine Yangian of \( \mathfrak{g}{\mathfrak{l}}_1 \), and the SHc algebra is established in detail. For generic λ we find explicit expressions for the low-lying \( {\mathcal{W}}_{\infty}\left[\lambda \right] \) modes in terms of the affine Yangian generators, and deduce...

Twisted sectors from plane partitions

Twisted sectors arise naturally in the bosonic higher spin CFTs at their free points, as well as in the associated symmetric orbifolds. We identify the coset representations of the twisted sector states using the description of \( {\mathcal{W}}_{\infty } \) representations in terms of plane partitions. We confirm these proposals by a microscopic null-vector analysis, and by...

A New Strategy for Quality Evaluation and Identification of Representative Chemical Components in Polygonum multiflorum Thunb.

and data analysis. Cheng Peng, Peng Li, and Yi-tao Wang conceived the study. Yun-xia Li and Xiao-hong Gong contributed equally to this paper. Acknowledgments The study was supported by Project cofunded ... Chinese Medicine, State Key Laboratory Breeding Base of Systematic Research, Development and Utilization of Chinese Medicine Resources, Chengdu 611137, China Correspondence should be addressed to Cheng

The antidepressant-like effects of pioglitazone in a chronic mild stress mouse model are associated with PPARγ-mediated alteration of microglial activation phenotypes

Background Discoveries that microglia-mediated neuroinflammation is involved in the pathological process of depression provided a new strategy for novel antidepressant therapy. Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor regulating inflammation and microglial polarization and, therefore, a potential target for resolving depressive disorders. Our...

Sustainable bioenergy production with little carbon debt in the Loess Plateau of China

Background As a key strategy for mitigating global climate change, bioenergy production by reducing CO 2 emissions plays an important role in ensuring sustainable development. However, land-use change by converting natural ecosystems into energy crop field could create a carbon debt at the beginning. Thus, the potential carbon debt calculation is necessary for determining a...

Development of a qualitative real-time PCR method to detect 19 targets for identification of genetically modified organisms

As the amount of commercially available genetically modified organisms (GMOs) grows recent years, the diversity of target sequences for molecular detection techniques are eagerly needed. Considered as the gold standard for GMO analysis, the real-time PCR technology was optimized to produce a high-throughput GMO screening method. With this method we can detect 19 transgenic...

The symmetry of large \( \mathcal{N} \) = 4 holography

For the proposed duality relating a family of \( \mathcal{N} \) = 4 superconformal coset models to a certain supersymmetric higher spin theory on AdS3, the asymptotic symmetry algebra of the bulk description is determined. It is shown that, depending on the choice of the boundary charges, one may obtain either the linear or the non-linear superconformal algebra on the boundary...

Higgsing the stringy higher spin symmetry

It has recently been argued that the symmetric orbifold theory of \( {\mathbb{T}}^4 \) is dual to string theory on AdS3 × S3 × \( {\mathbb{T}}^4 \) at the tensionless point. At this point in moduli space, the theory possesses a very large symmetry algebra that includes, in particular, a \( \mathcal{W} \) ∞ algebra capturing the gauge fields of a dual higher spin theory. Using...

Extended supersymmetry in AdS3 higher spin theories

We determine the asymptotic symmetry algebra (for fields of low spin) of the M × M matrix extended Vasiliev theories on AdS3 and find that it agrees with the \( \mathcal{W} \)-algebra of their proposed coset duals. Previously it was noticed that for M = 2 the supersymmetry increases from \( \mathcal{N}=2 \) to \( \mathcal{N}=4 \). We study more systematically this type of...

Structural heterogeneity and functional diversity of topologically associating domains in mammalian genomes

Recent chromosome conformation capture (3C) derived techniques have revealed that topologically associating domain (TAD) is a pervasive element in chromatin three-dimensional (3D) organization. However, there is currently no parameter to quantitatively measure the structural characteristics of TADs, thus obscuring our understanding on the structural and functional differences...

Micronucleus formation by single and mixed heavy metals/loids and PAH compounds in HepG2 cells

Humans and other organisms are exposed to multi-chemical mixtures including commonly found carcinogens such as polycyclic aromatic hydrocarbons (PAHs) and heavy metal/loids. The joint effects of these chemicals as beyond the binary mixtures have not been well characterised. In this study, we evaluated the combined genotoxicity of mixtures of PAHs and heavy metal/loids containing...

Rhein: A Review of Pharmacological Activities

Rhein (4, 5-dihydroxyanthraquinone-2-carboxylic acid) is a lipophilic anthraquinone extensively found in medicinal herbs, such as Rheum palmatum L., Cassia tora L., Polygonum multiflorum Thunb., and Aloe barbadensis Miller, which have been used medicinally in China for more than 1,000 years. Its biological activities related to human health are being explored actively. Emerging...

Shaping ability of ProTaper Universal, WaveOne and ProTaper Next in simulated L-shaped and S-shaped root canals

Background The purpose of this study was to compare the shaping ability of the ProTaper Universal (PTU; Dentsply Maillefer, Ballaigues, Switzerland), WaveOne (WO; Dentsply Maillefer) and ProTaper Next (PTN; Dentsply Maillefer) in simulated L-shaped and S-shaped root canals respectively. Methods 30 simulated L-shaped and 30 simulated S-shaped root canals in resin blocks were...

Norcantharidin Suppresses Colon Cancer Cell Epithelial-Mesenchymal Transition by Inhibiting the αvβ6-ERK-Ets1 Signaling Pathway

, AustraliaMichael Agrez AuthorsSearch for Cheng Peng in:Nature Research journals • PubMed • Google ScholarSearch for Zequn Li in:Nature Research journals • PubMed • Google ScholarSearch for Zhengchuan Niu in:Nature

The Dynamical Mechanism of Auto-Inhibition of AMP-Activated Protein Kinase

We use a novel normal mode analysis of an elastic network model drawn from configurations generated during microsecond all-atom molecular dynamics simulations to analyze the mechanism of auto-inhibition of AMP-activated protein kinase (AMPK). A recent X-ray and mutagenesis experiment (Chen, et al Nature 2009, 459, 1146) of the AMPK homolog S. Pombe sucrose non-fermenting 1 (SNF1...