The topology of non-Hermitian systems is drastically shaped by the non-Hermitian skin effect, which leads to the generalized bulk-boundary correspondence and non-Bloch band theory. The essential part ...in formulations of bulk-boundary correspondence is a general and computable definition of topological invariants. In this Letter, we introduce a construction of non-Hermitian topological invariants based directly on real-space wave functions, which provides a general and straightforward approach for determining non-Hermitian topology. As an illustration, we apply this formulation to several representative models of non-Hermitian systems, efficiently obtaining their topological invariants in the presence of non-Hermitian skin effect. Our formulation also provides a dual picture of the non-Bloch band theory based on the generalized Brillouin zone, offering a unique perspective of bulk-boundary correspondence.
In this work, large scale WO3 nanorods are prepared successfully by a facile one-step hydrothermal method. The as-synthesized samples are used as the photocatalysts for photocatalytic degradation of ...several organic dye molecules. The results show WO3 nanorods possess superior photocatalytic performance. In addition, electrochemical experiments of the samples as the working electrode present specific capacitance of 319.26 F g−1 at current density of 0.7 A g−1. After 6000 cycles, 83.2% of its initial capacitance is still retained. The as-fabricated symmetric supercapacitor light up ten blue light emitting diode (LED) indicators for more than 8 min in the voltage range of 0–1.4 V. The as-synthesized WO3 nanorods could be used in wastewater purification and electrochemical energy storage devices.
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•Large scale WO3 nanorods are obtained by simple hydrothermal route.•The prepared WO3 assembles were used as the photocatalyst and supercapacitor electrode.•The as-synthesized products could be used in wastewater purification and energy storage devices.
Subleading Weingartens Stanford, Douglas; Yang, Zhenbin; Yao, Shunyu
The journal of high energy physics,
02/2022, Letnik:
2022, Številka:
2
Journal Article
Recenzirano
Odprti dostop
A
bstract
Haar integrals over the unitary group contain subleading terms that are needed for unitarity. We study analogous effects in the time evolution operators of JT gravity and Brownian SYK. In ...JT gravity with bulk matter we find an explanation for the first sub-leading terms, and in Brownian SYK we find configurations that can explain the full series. An important role is played by slightly off-shell modes that are exponentially amplified by chaos.
The prevalence of inflammatory bowel disease (IBD), which includes ulcerative colitis (UC) and Crohn’s disease (CD), increases gradually worldwide in the past decades. IBD is generally associated ...with the change of the immune system and gut microbiota, and the conventional treatments usually result in some side effects. Bifidobacterium longum, as colonizing bacteria in the intestine, has been demonstrated to be capable of relieving colitis in mice and can be employed as an alternative or auxiliary way for treating IBD. Here, the mechanisms of the Bifidobacterium longum in the treatment of IBD were summarized based on previous cell and animal studies and clinical trials testing bacterial therapies. This review will be served as a basis for future research on IBD treatment.
An integrable road to a perturbative plateau Blommaert, Andreas; Kruthoff, Jorrit; Yao, Shunyu
The journal of high energy physics,
04/2023, Letnik:
2023, Številka:
4
Journal Article
Recenzirano
Odprti dostop
A
bstract
As has been known since the 90s, there is an integrable structure underlying two-dimensional gravity theories. Recently, two-dimensional gravity theories have regained an enormous amount of ...attention, but now in relation with quantum chaos — superficially nothing like integrability. In this paper, we return to the roots and exploit the integrable structure underlying dilaton gravity theories to study a late time, large
e
S
BH
double scaled limit of the spectral form factor. In this limit, a novel cancellation due to the integrable structure ensures that at each genus
g
the spectral form factor grows like
T
2
g
+1
, and that the sum over genera converges, realising a perturbative approach to the late-time plateau. Along the way, we clarify various aspects of this integrable structure. In particular, we explain the central role played by ribbon graphs, we discuss intersection theory, and we explain what the relations with dilaton gravity and matrix models are from a more modern holographic perspective.
In this paper, large scale hierarchically assembled Ni O nanosheets have been favorably fabricated through a facile hydrothermal route. The as-prepared Ni O nanosheet assembles were characterized in ...detail by various analytical techniques. The results showed these nanosheets present the thickness of about 30 nm and the surface area is 116.9 m2 g-1. These NiO nanosheet assembles were used as the working electrode materials in electrochemical tests, which demonstrated a specific capacitance value of 81.67 Fg -1at the current density of 0.5 Ag-1and excellent long cycle-life stability with 78.5% of its discharge specific capacitance retention after 3000 cycles at the current density of 0.5 Ag-1, revealing the as-synthesized NiO nanosheet assembles might be a promising electrode material for supercapacitor applications.
The power of Lorentzian wormholes Blommaert, Andreas; Kruthoff, Jorrit; Yao, Shunyu
The journal of high energy physics,
10/2023, Letnik:
2023, Številka:
10
Journal Article
Recenzirano
Odprti dostop
A
bstract
As shown by Louko and Sorkin in 1995, topology change in Lorentzian signature involves spacetimes with singular points, which they called crotches. We modify their construction to obtain ...Lorentzian semiclassical wormholes in asymptotically AdS. These solutions are obtained by inserting crotches on known saddles, like the double-cone or multiple copies of the Lorentzian black hole. The crotches implement swap-identifications, and are classically located near an extremal surface. The resulting Lorentzian wormholes have an instanton action equal to their area, which is responsible for topological suppression in any number of dimensions.
We conjecture that including such Lorentzian wormhole spacetimes is equivalent to path integrating over all mostly Euclidean smooth spacetimes. We present evidence for this by reproducing semiclassical features of the genus expansion of the spectral form factor, and of a late-time two point function, by summing over the moduli space of Lorentzian wormholes. As a final piece of evidence, we discuss the Lorentzian version of West-Coast replica wormholes.
The bulk-boundary correspondence is among the central issues of non-Hermitian topological states. We show that a previously overlooked "non-Hermitian skin effect" necessitates redefinition of ...topological invariants in a generalized Brillouin zone. The resultant phase diagrams dramatically differ from the usual Bloch theory. Specifically, we obtain the phase diagram of the non-Hermitian Su-Schrieffer-Heeger model, whose topological zero modes are determined by the non-Bloch winding number instead of the Bloch-Hamiltonian-based topological number. Our work settles the issue of the breakdown of conventional bulk-boundary correspondence and introduces the non-Bloch bulk-boundary correspondence.
A
bstract
We show that DSSYK amplitudes are reproduced by considering the quantum mechanics of a constrained particle on the quantum group SU
q
(1
,
1). We construct its left-and right-regular ...representations, and show that the representation matrices reproduce two-sided wavefunctions and correlation functions of DSSYK. We then construct a dynamical action and path integral for a particle on SU
q
(1
,
1), whose quantization reproduces the aforementioned representation theory. By imposing boundary conditions or constraining the system we find the
q
-analog of the Schwarzian and Liouville boundary path integral descriptions. This lays the technical groundwork for identifying the gravitational bulk description of DSSYK. We find evidence the theory in question is a sine dilaton gravity, which interestingly is capable of describing both AdS and dS quantum gravity.
Objective. This study focuses on the role of Zishen Huoxue Decoction (ZSHX) in reducing mitochondrial membrane potential and reducing the proportion of apoptosis through the mTORC1 signaling pathway. ...Methods. In our experiment, we first constructed an in vitro hypoxia/reoxygenation (H/R) model of H9C2 cells. Then, the cells were divided into control group, model group (hypoxia/reoxygenation, H/R), ZSHX, ZSHX + Rapa, low-dose ZSHX (100 μg/ml), and middle-dose ZSHX. High-dose ZSHX (400 μg/ml) group was treated with Zishen Huoxue Decoction (ZSHX). Western Blot was used to detect the expression of cell-related protein and RT-PCR was used to detect the expression of the cell-related gene in each group. Flow cytometry was used to assay for ROS content and the apoptotic ratio of H9C2 cells, Seahorse Live Cell Energy Meter was used to detect the Mitochondrial Respiratory Function in H9C2 Cells, and confocal laser scanning was used to detect the mitochondrial membrane potential of H9C2 cells. Results. Western Blot assay showed that the relative expression of mTOR and Raptor in the H/R group was significantly lower than that in the control group (n = 3, P<0.05). The expression of mTOR and Raptor was upregulated and the relative expression of 4E-BP1 was downregulated in the middle- and high-dose ZSHX groups (n = 3, P<0.05). In addition, the ROS content of H9C2 cells was detected by flow cytometry, showing the ROS synthesis in H/R group (78.31 + 6.14) higher than that in the control group (34.53 + 6.10) (n = 3, P<0.01). The ROS value was increased significantly after rapamycin inhibited mTOR (66.18 (+4.03 vs. 52.31 (+6.01), n = 3, P<0.05). The basal mitochondrial respiration and ATP production in H/R group were significantly lower than those in the control group (38.17 + 17.76); the mitochondrial leakage in H/R model group was significantly higher than that in the control group (H/R: 40.93 + 5.18 vs. Ctrl: 27.17 + 8.92, n = 4, P<0.05). The apoptotic rate of cardiomyocytes in the H/R model group (70.91 + 4.57) was significantly higher than that in the control group (14.52 + 2.37, n = 3, P<0.01), and Zishen Huoxue Decoction could decrease the apoptotic rate of hypoxic-reoxygenated cardiomyocytes (ZSHX: 18.24 + 4.17 vs. H/R: 78.91 + 3.48, n = 3, P<0.01). Conclusion. ZSHX Decoction has the effects of activating mTORC1, inhibiting the overexpression of 4E-BP1, inhibiting fatty acid oxidation, protecting the respiratory function of mitochondria, reducing ROS and apoptosis, and thus protecting myocardial cells from injury.
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