Non-Abelian Topological Bound States in the Continuum.

Bound states in the continuum (BICs), which are spatially localized states with energies lying in the continuum of extended modes, have been widely investigated in both quantum and classical systems. Recently, the combination of topological band theory with BICs has led to the creation of topological BICs that exhibit extraordinary robustness against disorder. However, the previously proposed topological BICs are only limited in systems with Abelian gauge fields. Whether non-Abelian gauge fields can induce topological BICs and how to experimentally explore these phenomena remains unresolved. Here, we report the theoretical and experimental realization of non-Abelian topological BICs, which are generated by the interplay between two inseparable pseudospins and can coexist in each pseudospin subspace. This unique characteristic necessitates non-Abelian couplings that lack any Abelian counterparts. Furthermore, the non-Abelian couplings can also offer a new avenue for constructing topological subspace-induced BICs at bulk dislocations. Those exotic phenomena are observed by non-Abelian topolectrical circuits. Our results establish the connection between topological BICs and non-Abelian gauge fields, and serve as the catalyst for future investigations on non-Abelian topological BICs across different platforms.

Association between diurnal temperature range and outpatient visits for urticaria disease in Lanzhou, China: a distributed lag nonlinear analysis.

BACKGROUND: A growing number of epidemiological studies have shown that daily temperatures are associated with urticaria. However, the relationship between daily changes in temperature and urticaria is unclear. OBJECTIVES: To assess the diurnal temperature difference (DTR) effects on urticaria outpatient visits in Lanzhou, China. METHODS: Urticaria outpatient visits data during 2011-2019 were collected from three major tertiary hospitals in Lanzhou. Daily temperature data from the official website of China Meteorological Administration. Assessment of the relationship between urticaria outpatient volume and DTR in Lanzhou City using a distributed lag nonlinear model. RESULTS: A total of 83,022 urticaria visits were enrolled. There was a nonlinear relationship between DTR and urticaria outpatient visits and a lagged effect of DTR impact. The effects of high DTR on urticaria visits were not seen in all populations but in the male population and in the 15-59 age group. High DTR (P95: 18.2 °C) was associated with a 27% (95% CI: 0.01, 60.53%) and 31% (95% CI: 1.60, 68.99%) increase in the number of urticaria visits in the 21-day lag effect for the male cohort and the 15-59 year old cohort, respectively, compared with 11.5 °C, respectively. CONCLUSIONS: Our study suggests that DTR is a potential risk factor for urticaria. The results of this study may provide a scientific basis for local governments to improve preventive measures in the health care system.

Laguerre Gaussian mode holography and its application in optical encryption.

Holography provides an approach to reconstructing both intensity and phase information, and has many applications for microscopic imaging, optical security, and data storage. Recently, the azimuthal Laguerre-Gaussian (LG) mode index, orbital angular momentum (OAM), has been implemented in holography technologies as an independent degree of freedom for high-security encryption. The radial index (RI) of LG mode, however, has not been implemented as an information carrier in holography. Here we propose and demonstrate the RI holography by using strong RI selectivity in the spatial-frequency domain. Furthermore, the LG holography is realized theoretically and experimentally with the (RI, OAM) spanning from (1, -15) to (7, 15), which leads to a 26bit LG-multiplexing hologram for high-security optical encryption. Based on LG holography, a high-capacity holographic information system can be constructed. In our experiments, a LG-multiplexing holography with a span of 217 independent LG channels has been realized, which is inaccessible at present for the OAM holography.

A regime shift in the Southeast Greenland marine ecosystem.

Two major oceanographic changes have recently propagated through several trophic levels in coastal areas of Southeast Greenland (SEG). Firstly, the amount of drift-ice exported from the Fram Strait and transported with the East Greenland Current (EGC) has decreased significantly over the past two decades, and a main tipping element (summer sea ice) has virtually disappeared since 2003 leading to a regime shift in oceanographic and ecological conditions in the region. The following 20-year period with low or no coastal sea ice is unique in the 200-year history of ice observations in the region, and the regime shift is also obvious in the volume of ice export through the Fram Strait after 2013. In the same period, the temperature of the EGC south of 73.5 N has increased significantly (>2°C) since 1980. Secondly, the warm Irminger Current, which advects warm, saline Atlantic Water into the region, has become warmer since 1990. The lack of pack ice in summer together with a warming ocean generated cascading effects on the ecosystem in SEG that are manifested in a changed fish fauna with an influx of boreal species in the south and the subarctic capelin further north. At higher trophic levels there has been an increase in the abundance of several boreal cetaceans (humpback, fin, killer, and pilot whales and dolphins) that are either new to this area or occur in historically large numbers. It is estimated that the new cetacean species in SEG are responsible for an annual predation level of 700,000 tons of fish. In addition, predation on krill species is estimated at >1,500,000 tons mainly consumed by fin whales. Simultaneously, there has been a reduction in the abundance and catches of narwhals and walruses in SEG and it is suggested that these species have been impacted by the habitat changes.

Phase-matched locally chiral light for global control of chiral light-matter interaction.

Locally chiral light is an emerging tool for probing and controlling molecular chirality. It can generate large and freely adjustable enantioselectivities in purely electric-dipole effects, offering its major advantages over traditional chiral light. However, the existing types of locally chiral light are phase-mismatched, and thus the global efficiencies are greatly reduced compared with the maximum single-point efficiencies or even vanish. Here, we propose a scheme to generate phase-matched locally chiral light. To confirm this advantage, we numerically show the robust highly efficient global control of enantiospecific electronic state transfer of methyloxirane at nanoseconds. Our work potentially constitutes the starting point for developing more efficient chiroptical techniques for the studies of chiral molecules.

Stable Atomic Magnetometer in Parity-Time Symmetry Broken Phase.

Random motion of spins is usually detrimental in magnetic resonance experiments. The spin diffusion in nonuniform magnetic fields causes broadening of the resonance and limits the sensitivity and the spectral resolution in applications like magnetic resonance spectroscopy. Here, by observation of the parity-time (PT) phase transition of diffusive spins in gradient magnetic fields, we show that the spatial degrees of freedom of atoms could become a resource, rather than harmful, for high-precision measurement of weak signals. In the normal phase with zero or low gradient fields, the diffusion results in dissipation of spin precession. However, by increasing the field gradient, the spin system undergoes a PT transition, and enters the PT symmetry broken phase. In this novel phase, the spin precession frequency splits due to spatial localization of the eigenmodes. We demonstrate that, using these spatial-motion-induced split frequencies, the spin system can serve as a stable magnetometer, whose output is insensitive to the inevitable long-term drift of control parameters. This opens a door to detect extremely weak signals in imperfectly controlled environments.

Non-Abelian Inverse Anderson Transitions.

Inverse Anderson transitions, where the flat-band localization is destroyed by disorder, have been wildly investigated in quantum and classical systems in the presence of Abelian gauge fields. Here, we report the first investigation on inverse Anderson transitions in the system with non-Abelian gauge fields. It is found that pseudospin-dependent localized and delocalized eigenstates coexist in the disordered non-Abelian Aharonov-Bohm cage, making inverse Anderson transitions depend on the relative phase of two internal pseudospins. Such an exotic phenomenon induced by the interplay between non-Abelian gauge fields and disorder has no Abelian analogy. Furthermore, we theoretically design and experimentally fabricate non-Abelian Aharonov-Bohm topolectrical circuits to observe the non-Abelian inverse Anderson transition. Through the direct measurements of frequency-dependent impedance responses and voltage dynamics, the pseudospin-dependent non-Abelian inverse Anderson transitions are observed. Our results establish the connection between inverse Anderson transitions and non-Abelian gauge fields, and thus comprise a new insight on the fundamental aspects of localization in disordered non-Abelian flat-band systems.

High-Dimensional Entanglement-Enabled Holography.

As an important imaging technique, holography has been realized with different physical dimensions of light, including polarization, wavelength, and time. Recently, quantum holography has been demonstrated by utilizing polarization entangled state with the advantages of high robustness and enhanced spatial resolution, comparing with classical holography. However, the polarization is only a two-dimensional degree of freedom, which greatly limits the capacity of quantum holography. Here, we propose a method to realize high-dimensional quantum holography by using high-dimensional orbital angular momentum (OAM) entanglement. A high-capacity OAM-encoded quantum holographic system can be obtained by multiplexing a wide range of OAM-dependent holographic images. Proof-of-principle experiments with four- and six-dimensional OAM entangled states have been implemented and verify the feasibility of our idea. Our experimental results also demonstrate that the high-dimensional quantum holography shows a high robustness to classical noise. What is more, the level of security of the holographic imaging encryption system can be greatly improved in our high-dimensional quantum holography.

Macrophage-mediated extracellular matrix remodeling after fat grafting in nude mice.

Clinical unpredictability and variability following fat grafting remain non-negligible problems due to the unknown mechanism of grafted fat retention. The role of the extracellular matrix (ECM), which renders cells with structural and biochemical support, has been ignored. This study aimed to clarify the ECM remodeling process, related cellular events, and the spatiotemporal relationship between ECM remodeling and adipocyte survival and adipogenesis after fat grafting. Labeled Coleman fat by the matrix-tracing technique was grafted in nude mice. The ECM remodeling process and cellular events were assessed in vivo. The related cytokines were evaluated by qRT-PCR. An in vitro cell migration assay was performed to verify the chemotactic effect of M2-like macrophages on fibroblasts. The results demonstrated that in the periphery, most of the adipocytes of the graft survived or regenerated, and the graft-derived ECM was gradually replaced by the newly-formed ECM. In the central parts, most adipocytes in the grafts died shortly after, and a small part of the graft-derived and newly-formed ECM was expressed with irregular morphology. Adipose ECM remodeling is associated with increased infiltration of macrophages and fibroblasts, as well as up-regulated expression of cytokines in the adipose tissue. To sum up, our results describe the various preservation mode of fat grafts after transplantation and underscore the importance of macrophage-mediated ECM remodeling in graft preservation after fat grafting. The appreciation and manipulation of underlying mechanisms that are operant in this setting stand to explore new therapeutic approaches and improve clinical outcomes of fat grafting.

Quantum Adversarial Transfer Learning.

Adversarial transfer learning is a machine learning method that employs an adversarial training process to learn the datasets of different domains. Recently, this method has attracted attention because it can efficiently decouple the requirements of tasks from insufficient target data. In this study, we introduce the notion of quantum adversarial transfer learning, where data are completely encoded by quantum states. A measurement-based judgment of the data label and a quantum subroutine to compute the gradients are discussed in detail. We also prove that our proposal has an exponential advantage over its classical counterparts in terms of computing resources such as the gate number of the circuits and the size of the storage required for the generated data. Finally, numerical experiments demonstrate that our model can be successfully trained, achieving high accuracy on certain datasets.

MiR-10b-3p alleviates cerebral ischemia/reperfusion injury by targeting Krüppel-like factor 5 (KLF5).

Although miR-10b-3p has been identified to be involved in cerebral ischemia injury, its impact and specific mechanism in cerebral ischemia injury remain unclear. The effects of Mir-10b-3p were investigated by establishing rat and cell models of ischemia/reperfusion (I/R) injury. Oxygen-glucose deprivation/reperfusion (OGD/R) was performed on pheochromocytoma-12 (PC12) cells. MiR-10b-3p expression levels in brain tissues and PC12 cells were detected by qRT-PCR. The impacts of miR-10b-3p on neurological deficits, infarct volume, inflammatory factor expression, in vivo brain water content, cell viability, and cell apoptosis were assessed. The relationship between miR-10b-3p and KLF5 was determined by TargetScan and luciferase reporter assay. The rescue experiments were performed to confirm the role of this axis in cerebral ischemia injury. Mir-10b-3p levels in rat brain tissue and PC12 cells were significantly decreased after I/R injury. MiR-10b-3p overexpression obviously reduced neurological deficits, infarct volume, brain water content, inflammatory factors expression, and neuronal apoptosis in the brain of ischemia-stroked rats. Meanwhile, miR-10b-3p upregulation also inhibited cell viability and apoptosis of OGD/R-induced PC12 cells. Besides, KLF5 was identified as a target of miR-10b-3p, and rescue experiments revealed that KLF5 was involved in the regulation of miR-10b-3p in ischemic injury. Our results demonstrated that miR-10b-3p had the neuroprotective effects against ischemia injury by targeting KLF5 and provided a potential underlying target for ischemic stroke treatment.

Moiré Quasibound States in the Continuum.

The novel physics of twisted bilayer graphene has motivated extensive studies of magic-angle flat bands hosted by moiré structures in electronic, photonic, and acoustic systems. On the other hand, bound states in the continuum (BICs) have also attracted great attention in recent years because of their potential applications in the field of designing superior optical devices. Here, we combine these two independent concepts to construct a new optical state in a twisted bilayer photonic crystal slab, which is called as moiré quasi-BIC, and numerically demonstrate that such an exotic optical state possesses dual characteristics of moiré flat bands and quasi-BICs. To illustrate the mechanism for the formation of moiré flat bands, we develop an effective model at the center of the Brillouin zone and show that moiré flat bands could be fulfilled by balancing the interlayer coupling strength and the twist angle around the band edge above the light line. Moreover, by decreasing the twist angle of moiré photonic crystal slabs with flat bands, it is shown that the moiré flat-band mode at the Brillouin center gradually approaches a perfect BIC, where the total radiation loss from all diffraction channels is significantly suppressed. To clarify the advantage of moiré quasi-BICs, enhanced second-harmonic generation (SHG) is numerically proven with a wide-angle optical source. The efficiency of SHG assisted by designed moiré quasi-BICs can be greatly improved compared with that based on dispersive quasi-BICs with similar quality factors.

Protective Effect of Topiroxostat on Myocardial Injury Induced by Lipopolysaccharide.

BACKGROUND: Myocardial injury induced by sepsis is the most common cause of death. Topiroxostat has been found to have organ protective effects, but its role in septic shock-related cardiomyocyte damage is still unclear and needs further study. MATERIAL AND METHODS: An endotoxemic shock model in rats was constructed. After topiroxostat treatment, hemodynamic parameters, myocardial injury marker enzymes, oxidative stress, myocardial injury, and apoptosis were measured by polyphysiograph, enzyme-linked immunosorbent assay, hematoxylin and eosin staining, TUNEL staining, and western blot. During in vitro experiments, the effect of topiroxostat on cell vitality, oxidative stress, inflammatory factors, apoptosis-related markers, phosphorylated-p65 (p-p65) and p65 expressions were measured by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), flow cytometry, enzyme-linked immunosorbent assay, quantitative real-time polymerase chain reaction, and western blot. RESULTS: Topiroxostat improved myocardial dysfunction and superoxide dismutase activity while suppressing levels of creatine kinase, lactate dehydrogenase and malondialdehyde in serum of endotoxemic shock rats. Additionally, topiroxostat augmented dry-wet weight ratios of the hearts in rats. Meanwhile, topiroxostat was proved to alleviate interstitial edema and apoptosis in myocardial tissues of endotoxemic shock rats. During in vitro experiments, topiroxostat pretreatment elevated lipopolysaccharide (LPS)-induced H9c2 cell vitality, and alleviated oxidative stress and inflammation. Moreover, topiroxostat pretreatment downregulated apoptosis-related markers, p-p65, and p-p65/p65 levels in LPS-induced H9c2 cells. CONCLUSIONS: Topiroxostat attenuated LPS-induced myocardial injury via repressing apoptosis and oxidative stress.

Fentanyl alleviates intestinal mucosal barrier damage in rats with severe acute pancreatitis by inhibiting the MMP-9/FasL/Fas pathway.

BACKGROUND: Fentanyl is an analgesic used against pancreatitis-related pain, while whether it ameliorates severe acute pancreatitis (SAP) has yet to be checked. This study aims to determine fentanyl-delivered effect on SAP and the mechanism underlying this effect. METHODS: Rat SAP models were established, following fentanyl treatment. The serum activity of amylase (AMY), lipase (LIP), and diamine oxidase (DAO) was detected by enzyme-linked immunosorbent assay (ELISA). Histological examination was performed in the pancreatic and intestinal tissues with hematoxylin-eosin staining. After transfection with matrix metalloproteinase (MMP) 9 overexpression plasmids, Caco-2 monolayers were treated with fentanyl and subsequently exposed to lipopolysaccharide (LPS). The transepithelial electrical resistance (TEER) value was determined in rat intestinal mucosa through an Ussing chamber assisted by Analyze & Acquire, and in Caco-2 cell monolayers through a voltohmmeter. Intestinal mucosa and paracellular permeabilities were determined by fluorescein isothiocyanate (FITC)-labeled dextran assay. The expressions of ZO-1, Occludin, MMP9, Fas and Fas ligand (FasL) in rat intestinal mucosa and/or Caco-2 monolayers were analyzed by qRT-PCR or/and western blot. RESULTS: Fentanyl alleviated SAP-related histological alterations in the pancreas and intestines, reduced the elevated levels of SAP-related AMY, LIP, and DAO, but promoted the levels of ZO-1 and Occludin. In SAP rats and Caco-2 monolayers, SAP-related or LPS-induced TEER value decreases, permeability increases, and increases in the expressions of MMP9, Fas, and FasL were reversed partly by fentanyl. Notably, MMP9 overexpression could reverse the above fentanyl-delivered in vitro effects. CONCLUSIONS: Fentanyl alleviates intestinal mucosal barrier damage in rats with SAP by inhibiting the MMP9/FasL/Fas pathway.

Adipose Collagen Fragment: A Novel Adipose-Derived Extracellular Matrix Concentrate for Skin Filling.

BACKGROUND: Skin filler is an option for treating skin aging and wrinkles; however, currently used fillers are limited by poor biocompatibility, rapid degradation, and possible hypersensitivity reactions. Autologous adipose tissue-derived products have been recognized as promising options for skin rejuvenation. OBJECTIVES: This study aimed to develop a novel adipose-derived product for skin filling. METHODS: Adipose collagen fragment (ACF) was prepared through pulverization, filtration, and centrifugation. The macrography, structure, types of collagen, and cell viability of ACF were evaluated by immunostaining, western blotting, and cell culture assays. ACF, nanofat, and phosphate-buffered saline (9 spots/side, 0.01 mL/spot) were intradermally injected in the dorsal skin of 36 female BALB/c nude mice; the skin filling capacity and the collagen remodeling process were then investigated. Twenty-one female patients with fine rhytides in the infraorbital areas were enrolled and received clinical applications of ACF treatment. Therapeutic effects and patients' satisfaction scores were recorded. RESULTS: The mean [standard deviation] yield of ACF from 50 mL of Coleman fat was 4.91 [0.25] mL. ACF contained nonviable cells and high levels of collagen I, collagen IV, and laminin. Fibroblasts and procollagen significantly increased in ACF and ACF-treated dermis (P < 0.05). Overall, 85.7% of patients were satisfied with the therapy results, and no infections, injection site nodules, or other unwanted side effects were observed. CONCLUSIONS: ACF significantly improved dermal thickness and collagen synthesis and may serve as a potential autologous skin filler.

Adipose Collagen Fragment: A Novel Adipose-Derived Extracellular Matrix Concentrate for Skin Filling.

BACKGROUND: Skin filler is an option for treating skin aging and wrinkles; however, currently used fillers are limited by poor biocompatibility, rapid degradation, and possible hypersensitivity reactions. Autologous adipose tissue-derived products have been recognized as promising options for skin rejuvenation. OBJECTIVES: This study aimed to develop a novel adipose-derived product for skin filling. METHODS: Adipose collagen fragment (ACF) was prepared through pulverization, filtration, and centrifugation. The macrography, structure, types of collagen, and cell viability of ACF were evaluated by immunostaining, western blotting, and cell culture assays. ACF, nanofat, and phosphate-buffered saline (9 spots/side, 0.01 mL/spot) were intradermally injected in the dorsal skin of 36 female BALB/c nude mice; the skin filling capacity and the collagen remodeling process were then investigated. Twenty-one female patients with fine rhytides in the infraorbital areas were enrolled and received clinical applications of ACF treatment. Therapeutic effects and patients' satisfaction scores were recorded. RESULTS: The mean [standard deviation] yield of ACF from 50 mL of Coleman fat was 4.91 [0.25] mL. ACF contained nonviable cells and high levels of collagen I, collagen IV, and laminin. Fibroblasts and procollagen significantly increased in ACF and ACF-treated dermis (P < 0.05). Overall, 85.7% of patients were satisfied with the therapy results, and no infections, injection site nodules, or other unwanted side effects were observed. CONCLUSIONS: ACF significantly improved dermal thickness and collagen synthesis and may serve as a potential autologous skin filler.

Effect of Mn2+ on the phosphorus removal and bioflocculation under anoxic condition.

Manganese ion (Mn2+) generated from metallurgical, steel making and chemical industries enters sewage treatment plants and affects the sludge activity and flocculation. The effect of Mn2+ on the removal of chemical oxygen demand (COD) and total phosphorus (TP) and sludge activity were investigated in anoxic zone of an anaerobic/anoxic/oxic (A2O) process. The compositions and structures of extracellular polymeric substances (EPS) were characterized using three-dimensional excitation emission matrix fluorescence spectroscopy (3D-EEM), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) to reveal the relationship among Mn2+, EPS and sludge flocculation. The results showed that low concentration of Mn2+ (<5 mg/L) improved removal efficiencies of COD and TP and increased the activity of alkaline phosphatase, acid phosphatase and dehydrogenase. Meanwhile, the addition of Mn2+ increased total EPS, sludge contact angle, Zeta potential and sludge particle size, and thus enhanced sludge flocculation. However, high concentration of Mn2+ (>10 mg/L) hindered microbial flocculation and reduced removal efficiencies of the pollutants. When Mn2+was 5 mg/L, removal efficiencies of COD and TP reached 65% and 90%, respectively. Sludge flocculation was the best and SVI was 70.56 mL/g. The changes of Mn2+ concentration caused deviation of groups' compositions in LB-EPS and TB-EPS, where the main components were always protein (PN) and polysaccharide (PS). The addition of Mn2+ resulted in the degradation of humic acids. However, it did not give rise to significant morphology changes of EPS.

Velocity measurement of an arbitrary three-dimensional moving object by using a novel modulated field.

The rotational Doppler effect caused by vortex beam carrying orbital angular momentum is recently used to estimate the rotational velocity of the object. However, the vortex beam only has the spiral phase distribution in one dimension, which means that only the rotational movement of the object would introduce the frequency shift. Also, the vortex beam has a spatial amplitude distribution of doughnut-shaped, which is not suitable for many application scenarios. To simultaneously measure the velocity of an arbitrary three-dimensional moving object, we propose theoretically and demonstrate experimentally an effective method by constructing a novel modulated field. Different from the plane wave and the vortex beam, the modulated field has linear phase distribution in azimuth and elevation directions. In addition, the modulated field has the maximal radiation intensity in the center, which avoids the beam divergence of the vortex beam. By decomposing the frequency shift caused by the radial, azimuth and elevation movements, we realize the velocity measurement in three dimensions. Experiments in a microwave system show that the estimated velocity errors are lower than 6.0%.

Optimization and robustness of the topological corner state in second-order topological photonic crystals.

The second-order topological photonic crystal with the 0D corner state provides a new way to investigate cavity quantum electrodynamics and develop topological nanophotonic devices with diverse functionalities. Here, we report on the optimization and robustness of the topological corner state in the second-order topological photonic crystal both in theory and in experiment. The topological nanocavity is formed based on the 2D generalized Su-Schrieffer-Heeger model. The quality factor of the corner state is optimized theoretically and experimentally by changing the gap between two photonic crystals or just modulating the position or size of the airholes surrounding the corner. The fabricated quality factors are further optimized by the surface passivation treatment which reduces surface absorption. A maximum quality factor of the fabricated devices is about 6000, which is the highest value ever reported for the active topological corner state. Furthermore, we demonstrate the robustness of the corner state against strong disorders including the bulk defect, edge defect, and even corner defect. Our results lay a solid foundation for further investigations and applications of the topological corner state, such as the investigation of a strong coupling regime and the development of optical devices for topological nanophotonic circuitry.

Optically Unstable Phase from Ion-Ion Interactions in an Erbium-Doped Crystal.

Optical many-body systems naturally possess strong light-matter interactions and are thus of central importance for photonic applications. However, these applications are so far limited within the regime of intrinsic dynamically stable phases, and the possibility of unstable phases remains unidentified. Here we experimentally revealed a new dynamical phase of intrinsic optical instability by using a continuous-wave laser to drive an erbium-doped crystal. The transmission through the sample became unstable for intense laser inputs, and transient net gain was observed if the light passed the sample twice. The phase transition, between states in and out of a dynamical equilibrium, was induced by the dipole-dipole interactions between nearby erbium ions.