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Abstract The presence of topological flat minibands in moiré materials provides an opportunity to explore the interplay between topology and correlation. In this work, we study moiré minibands in topological insulator films with two hybridized surface states under a moiré superlattice potential created by two-dimensional insulating materials. We show the lowest conduction (highest valence) Kramers’ pair of minibands can be $${{\mathbb{Z}}}_{2}$$ Z 2 non-trivial when the minima (maxima) of moiré potential approximately form a hexagonal lattice with six-fold rotation symmetry. Coulomb interaction can drive the non-trivial Kramers’ minibands into the quantum anomalous Hall state when they are half-filled, which is further stabilized by applying external gate voltages to break inversion. We propose the monolayer Sb2 on top of Sb2Te3 films as a candidate based on first principles calculations. Our work demonstrates the topological insulator based moiré heterostructure as a potential platform for studying interacting topological phases.

We investigate the phase diagram at the boundary of an infinite two-dimensional cluster state subject to bulk measurements using tensor network methods. The state is subjected to uniform measurements M=cosθZ+sinθX on the lower boundary qubits and in all bulk qubits. Our results show that the boundary of the system exhibits volume-law entanglement at the measurement angle θ=π/2 and area-law entanglement for any θ

A correlated insulator has recently been observed in twisted bilayer WSe2 moiré superlattices. Here, Bi and Fu present a theory and predict the insulating state to be an excitonic density wave as well as a spin-valley superfluid, which can be tested by optical pump-probe experiments.

The responses of anammox consortia to typical antibiotics sulfadiazine (SDZ) and chlortetracycline (CTC) were evaluated on the aspects of general performance, microbial activity, diversity and abundance of antibiotic resistance genes (ARGs), and microbial host of ARGs in anammox system. Results showed the anammox consortia had a stable performance and great resistance to 10 mg/L of SDZ, while 1 mg/L of CTC induced an unrecoverable inhibitory influence on nitrogen removal performance and anammox activity without any special treatment. The absolute abundances of anammox functional genes (nirS, hzsA and hdh) were stimulated by the acclimation to SDZ stress, however, they were much lower than the initial levels under CTC stress. In anammox consortia, ARGs comprised 18 types (94 subtypes) derived from over 20 genera. Strikingly, the anammox bacteria (AnAOB) “Ca. Brocadia” occupied 46.81% of the SDZ resistance genes (sul1 and sul2) and 38.63% of CTC resistance genes (tetX, tetG and rpsJ), and thus were identified as the dominant antibiotic resistance bacteria (ARB). Therefore, harboring the corresponding ARGs by AnAOB could be the primary protective mechanism to interpret the resistance of anammox consortia to antibiotics stress. Meanwhile, co-occurring of ARGs in anammox consortia suggested the synergistic cooperation of different ARGs could be an essential strategy to alleviate the SDZ and CTC stress. The present study proposed a new interpretation of possible mechanism that cause antibiotic resistance of anammox consortia.

Copper tin sulfides (CTSs) have widely been investigated as electrode materials for supercapacitors owing to their high theoretical pseudocapacitances. However, the poor intrinsic conductivity and volume change during redox reactions hindered their electrochemical performances and broad applications. In this study, carbon quantum dots (CQDs) were employed to modify CTSs. The structures and morphologies of obtained materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). XRD revealed CTSs were composed of Cu2SnS3 and Cu4SnS4, and TEM suggested the decoration of CQDs on the surface of CTSs. With the decoration of CQDs, CTSs@CQDs showed a remarkable specific capacitance of 856 F·g−1 at 2 mV·s−1 and a high rate capability of 474 F·g−1 at 50 mV·s−1, which were superior to those of CTSs (851 F·g−1 at 2 mV·s−1 and 192 F·g−1 at 50 mV·s−1, respectively). This was mainly ascribed to incorporation of carbon quantum dots, which improved the electrical conductivity and alleviated volume change of CTSs during charge/discharge processes.

Porcine deltacoronavirus (PDCoV) is a novel enteric coronavirus and is becoming one of the major causative agents of diarrhea in pig herds in recent years. To date, there are no commercial vaccines or antiviral pharmaceutical agents available to control PDCoV infection. Therefore, developing a reliable strategy against PDCoV is urgently needed. In this study, to observe the antiviral activity of RNA interference (RNAi), four short hairpin RNAs (shRNAs) specific to the nucleocapsid (N) gene of PDCoV were designed and tested in vitro. Of these, a double-shRNA-expression vector, designated as pSil-double-shRNA-N1, was the most effectively expressed, and the inhibition of PDCoV replication was then further evaluated in neonatal piglets. Our preliminary results reveal that plasmid-based double-shRNA-expression targeting the N gene of PDCoV can significantly protect LLC-PK1 cells and piglets from pathological lesions induced by PDCoV. Our study could benefit the investigation of the specific functions of viral genes related to PDCoV infection and offer a possible methodology of RNAi-based therapeutics for PDCoV infection.

Fe-dependent nitrate reduction by anammox consortia could serve as a valuable autotrophic denitrification process for wastewater treatment. However, influences of temperature, pH, and Fe/NO3-N ratio on this biochemical process have not been studied. The present study investigated individual and interactive effects of aforementioned parameters on nitrate removal performance and bioactivity of anammox consortia via a series of batch assays. Enzymes activity of nitrate reductase (NAR) and hydrazine dehydrogenase (HDH) of anammox consortia had high consistency with nitrogen removal performance and significantly depended on temperature and Fe/NO3-N ratio, while the narG and hdh genes expression were drastically depressed by extreme temperature. Models developed by response surface methodology (RSM) showed the significance of individual parameter followed by Fe/NO3-N ratio > temperature > pH, while combined effects of temperature versus Fe/NO3-N ratio exerted the most significant impacts. The pH in range of 4.0–8.0 had less influence. The optimum condition for nitrate removal efficiency (NRE) > 90% and total nitrogen removal efficiency (TNRE) > 75% was 4.0–7.4 for pH, 25.5–30.0 °C for temperature, and 31–48 for Fe/NO3-N molar ratio. The maximum NRE and TNRE could be 98.68% and 79.42%, respectively, under the condition of pH = 4.00, temperature = 28.5 °C and Fe/NO3-N ratio = 37.4. The models showed good dependability for simulation nitrogen removal performance by anammox in the real semiconductor wastewater.

Continuous phase transitions associated with the onset of a spontaneously broken symmetry are thought to be successfully described by the Landau-Ginzburg-Wilson-Fisher theory of fluctuating order parameters. In this work, we show that such transitions can admit new universality classes which cannot be understood in terms of a theory of order parameter fluctuations. We explicitly demonstrate continuous time reversal symmetry breaking quantum phase transitions of 3+1-D bosonic systems described by critical theories expressed in terms of a deconfined gauge theory with massless Dirac fermions instead of the fluctuating Ising order parameter. We dub such phase transitions “Landau transitions beyond Landau description” (LBL). A key feature of our examples is that the stability of the LBL fixed points requires a crucial global symmetry, which is nonanomalous, unbroken, and renders no symmetry protected topological phase throughout the phase diagram. Despite this, there are elementary critical fluctuations of the phase transition that transform projectively under this symmetry group. We also construct examples of other novel quantum critical phenomena, notably a continuous Landau-forbidden deconfined critical point between two Landau-allowed phases in 3+1-D.

Paramagnetic spin systems with spontaneously broken spatial symmetries, such as valence bond solid phases, can host topological defects carrying nontrivial quantum numbers, which enables the paradigm of deconfined quantum criticality. In this work, we study the properties of topological defects in valence plaquette solid (VPS) phases on square and cubic lattices. We show that the defects of the VPS order parameter, in addition to possessing nontrivial quantum numbers, have fracton mobility constraints deep in the VPS phase, which has been overlooked previously. The spinon inside a single vortex cannot move freely in any direction, while a dipolar pair of vortices with spinon pairs can only move perpendicularly to its dipole moment. These mobility constraints, while they persist, can potentially inhibit the condensation of vortices and preclude a continuous transition from the VPS to the Néel antiferromagnet. Instead, the VPS melting transition can be driven by proliferation of spinon dipoles. For example, we argue that a two-dimensional VPS can melt into a stable gapless phase in the form of an algebraic bond liquid with algebraic correlations and long-range entanglement. Such a bond liquid phase yields a concrete example of the elusive two-dimensional Bose metal with symmetry fractionalization. We also study the three-dimensional valence plaquette and valence cube ordered phase, and demonstrate that the topological defects therein also have fractonic dynamics. Possible nearby phases after melting the valence plaquettes or cubes are also discussed.

The experimental observation of superconductivity in doped semimetals and semiconductors, where the Fermi energy is comparable to or smaller than the characteristic phonon frequencies, is not captured by the conventional theory. In this paper, we propose a mechanism for superconductivity in ultralow-density three-dimensional Dirac materials based on the proximity to a ferroelectric quantum critical point. We derive a low-energy theory that takes into account both the strong Coulomb interaction and the direct coupling between the electrons and the soft phonon modes. We show that the Coulomb repulsion is strongly screened by the lattice polarization near the critical point even in the case of a vanishing carrier density. Using a renormalization group analysis, we demonstrate that the effective electron-electron interaction is dominantly mediated by the transverse phonon mode. We find that the system generically flows towards strong electron-phonon coupling. Hence, we propose a new mechanism to simultaneously produce an attractive interaction and suppress strong Coulomb repulsion, which does not require retardation. For comparison, we perform the same analysis for covalent crystals, where lattice polarization is negligible. We obtain qualitatively similar results, though the screening of the Coulomb repulsion is much weaker. We then apply our results to study superconductivity in the low-density limit. We find a strong enhancement of the transition temperature upon approaching the quantum critical point. Finally, we also discuss scenarios to realize a topological p-wave superconducting state in covalent crystals close to the critical point.

Continuous quantum phase transitions beyond the conventional paradigm of fluctuations of a symmetry-breaking order parameter are challenging for theory. These phase transitions often involve emergent deconfined gauge fields at the critical points as demonstrated in phase transitions between different broken-symmetry states of 2+1-dimensional quantum magnets, as well as those between symmetry-protected topological (SPT) phases. In this paper, we present several examples of deconfined quantum critical points between SPT phases in 3+1-D for both bosonic and fermionic systems. These critical theories can be formulated as non-Abelian gauge theories either in the infrared-free regime or in the conformal window when they flow to the Banks-Zaks fixed points. We explicitly demonstrate several interesting quantum critical phenomena. We describe situations in which the same phase transition allows for multiple universality classes controlled by distinct fixed points. We exhibit the possibility—which we dub “unnecessary quantum critical points”—of stable generic continuous phase transitions within the same phase. We present examples of interaction-driven, band-theory-forbidden, continuous phase transitions between two distinct band insulators. The understanding we develop leads us to suggest an interesting possible 3+1-D field theory duality between SU(2) gauge theory coupled to one massless adjoint Dirac fermion and the theory of a single massless Dirac fermion augmented by a decoupled topological field theory.

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·g−1 at a current density of 100 mA·g−1), good capacity retention (200.6 mAh·g−1 after 50 cycles at a current density of 100 mA·g−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.

In this paper we construct bosonic short range entangled (SRE) states in all spatial dimensions by coupling a ${{\mathbb{Z}}}_{2}$ gauge field to fermionic SRE states with the same symmetries , and driving the ${{\mathbb{Z}}}_{2}$ gauge field to its confined phase. We demonstrate that this approach allows us to construct many examples of bosonic SRE states, and we demonstrate that the previous descriptions of bosonic SRE states such as the semiclassical nonlinear sigma model field theory and the Chern–Simons field theory can all be derived using the fermionic SRE states.

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]

Abstract Background "Swiss Cheese" ventricular septal defects represent a serious congenital heart disease with suboptimal clinical outcomes and a lack of consensus regarding its management. This study presents mid-term follow-up results of surgical repairs for "Swiss Cheese" ventricular septal defects, utilizing the two-patch and right ventricle apex-exclusion technique. Methods A retrospective review was conducted on 13 patients who underwent surgical repair utilizing the two-patch and right ventricle apex-exclusion technique at our institution between May 2014 and October 2021. The procedure involved the closure of defects in the outflow tract ventricular septal and the apex trabecular ventricular septal regions using two patches, with concurrent exclusion of the right ventricular apex from the right ventricular inflow tract. Results Median follow-up was 4.9 ± 2.1 years (range: 2–9 years). All cases were successful without mortality or major complications. Two years post-surgery, cardiac magnetic resonance revealed median values for left ventricular ejection fraction, right ventricular ejection fraction, left ventricular end-diastolic volume and right ventricular end-diastolic volume of 63.9% ± 1.8% (range: 61–67%), 49.2% ± 2.6% (range: 46–55%), 39.15 ± 2.11 ml (range: 36.2–42.7 ml), 44.55 ± 3.33 ml (range: 38.7–48.6 ml), respectively. No thrombosis occurred. The latest echocardiography results confirmed normal cardiac function in all cases. Conclusions The surgical repair of "Swiss Cheese" ventricular septal defects utilizing the two-patch and right ventricle apex-exclusion technique is a viable approach with favorable mid-term outcomes. More cases and long-term follow-up results are needed to validate the feasibility and safety of this technique.

Projects involve inter-organizational relationship cognition, which is central to collaborative engineering project value added. Interest in value added in the project lifecycle is mounting and gaining increasing attention in the research literature. However, little is known about how inter-organizational relationship cognition facilitates value added and how such cognition pushes a project toward higher end-states of value. The existing literature mainly analyzes and studies value added on functional analysis and cost control. There are predominantly static analyses of the factors that influence value added in studies. The guiding role of value added has not been adequately explored in the studies on the influencing factors of value added. Utilizing a combination of Structural Equation Modeling (SEM) and Fuzzy Cognitive Maps (FCMs), this study addresses how inter-organizational relationship cognition influences engineering project value added, identifying complex structures of interaction and cognition dynamics. Results indicate that: (1) A hybrid SEM–FCM method can be able to model dynamic interactions between inter-organizational relationship cognition and value added; (2) trust and shared vision have positive effects on in-role behavior and extra-role behavior. Shared vision has a negative effect on opportunistic behavior. In-role behavior and extra-role behavior have a positive impact on value added, while opportunistic behavior has a negative impact. Organizational behavior is an important mediating variable to explain the interaction between inter-organizational relationship cognitions and value added. This hybrid method explores the potential mechanisms of inter-organizational relationship cognition on project value added from novel perspectives on construction project management practices, proposing practical advice for further project management.

Background Current drugs for treating osteoporosis may lead to toxic side effects. Echinacoside (ECH) is a natural small molecule drug. This study examined and compared the therapeutic effects of cross-linker (CL)-ECH and ECH-free nanoparticles on osteoporosis. Methods Echinocandin-based CL-ECH nanoparticles were prepared, and the nanoparticle size and drug loading were optimized and characterized by adjusting the ratio. The antioxidant effect of CL-ECH nanoparticles on bone marrow-derived macrophages (BMDMs) was analyzed using flow cytometry, immunofluorescence staining and quantitative real-time polymerase chain reaction (qRT-PCR). Bone marrow stromal cells (BMSCs)-based detection of bone-producing effects was conducted using alkaline phosphatase (ALP), Alizarin Red S (ARS) and qRT-PCR. TRAP, phalloidin staining, and qRT-PCR was performed to detect osteogenesis-inhibiting effect on BMDMs. CL-ECH nanoparticles were applied to treat an ovariectomized (OVX) mouse model at low doses. Results Compared to ECH, CL-ECH nanoparticles suppressed oxidative stress in BMDMs by promoting NRF-2 nuclear translocation, which inhibited the production of both reactive oxygen species (ROS) and osteoclast production through downregulating NF-κB expression, with limited effect on the osteogenesis of BMSCs. In vivo studies showed that low-dose CL-ECH nanoparticles markedly improved bone trabecular loss compared to ECH administration in the treatment of osteoporosis. Conclusions The current discoveries provided a solid theoretical foundation for the development of a new generation of anti-bone resorption drugs and antiosteoporosis drugs.

The porous metal foams are potential to integrate phase change materials (PCMs) to form the shape-stabilized composited PCMs for the applications of thermal energy management and temperature regulation. However, the effect of porosity distribution of foam keeps challenging in designing such PCM-based composites. In this work, the closed-cell graded porosity foams (GPFs) involving various gradient directions and gradient differences of porosity are engineered by shrinking Voronoi tessellations to achieve precisely tunable microstructure. Then the GPF/PW composite is formed by integrating paraffin wax (PW) in each pore and its melting performance is investigated by the computational model, which is validated by the melting experiment of a specific sample. The investigations on the gradient configurations of foams reveal that the gradient direction and gradient difference of porosity have significant influences on the pore-scale melting behavior, liquid fraction variation in time and overall energy storage efficiency of PW. The positive gradient variation along the direction of heating source and the moderate gradient difference, i.e. 20% or 30%, are beneficial to improve the melting behavior of graded models. In contrast to the uniform model, the complete melting time of the graded models can maximum shorten by 5.6%, 3.8% and 3.7% for the bottom, lateral and top heating modes, respectively.

In the tip clearance flow, the dominant vortex is the tip leakage vortex (TLV), which has a significant impact on the hydraulic and cavitation performance of axial flow machineries. In order to reveal the impact mechanism of the gap size on the TLV, gap flows with two gap sizes, i.e., τ=0.2 (2 mm) and τ=1.0 (10 mm), are numerically investigated. A NACA0009 hydrofoil is selected to create the gap flow, with an incoming velocity of 10 m/s and an attack angle of 10 deg. The results show that the two flow cases are significantly different in terms of vortex feature and the leakage flow distribution. In the small gap, a type of jet-pattern flow appears, whereas a type of rolling-pattern flow passes over the large gap. The vertical velocity gradient of the leakage flow has a decisive influence on the TLV trajectory. In addition, for the large gap, the axial velocity in the vortex center exceeds the incoming flow. This jet-like state of axial velocity can be maintained for a long distance, making the vortex more stable. However, the axial velocity in the case of τ=0.2 cannot stay at the jet-like state and rapidly switches to a wake-like state. [ABSTRACT FROM AUTHOR]

Introduction Post-induction hypotension (PIH) is a common event in elderly surgical patients and is associated with increased postoperative morbidity and mortality. This study aims to develop and validate a PIH prediction model for elderly patients undergoing elective non-cardiac surgery to identify potential PIH in advance and help to take preventive measures.Methods and analysis A total of 938 elderly surgical patients (n=657 for development and internal validation, n=281 for temporal validation) will be continuously recruited at The First Affiliated Hospital of Soochow University in Suzhou, China. The main outcome is PIH during the first 15 min after anaesthesia induction or before skin incision (whichever occurs first). We select candidate predictors based on published literature, professional knowledge and clinical expertise. For model development, we will use the least absolute shrinkage and selection operator regression analysis and multivariable logistic regression. For internal validation, we will apply the bootstrapping technique. After model development and internal validation, temporal validation will be conducted in patients recruited in another time period. We will use the discrimination, calibration and max-rescaled Brier score in the temporal validation cohort. Furthermore, the clinical utility of the prediction model will be assessed using the decision curve analysis, and the results will be presented in a nomogram and a web-based risk calculator.Ethics and dissemination Ethical approval was obtained from the Ethics Committee of the First Affiliated Hospital of Soochow University (Approval No. 2023-012). This PIH risk prediction model will be published in a peer-reviewed journal.Trial registration number ChiCTR2200066201.

ObjectiveWe report a surgical method (sutureless technique), combined with vertical vein incision and pulmonary veins unroofed (semisutureless technique), to correct infracardiac total anomalous pulmonary venous connection (TAPVC).Materials and methodsThe clinical characteristics of 21 patients, who were diagnosed with infracardiac TAPVS between February 2017 and March 2022, were retrospectively analyzed. These patients were divided into three groups according to different surgical methods: conventional surgery group, sutureless technique group, and semisutureless technique group. The conventional surgery group enrolled five patients with a median age of 16 days (interquartile range, 9–27 days) and a median weight of 3.25 kg (interquartile range, 3.1–3.42 kg). In this group, no preoperative pulmonary vein obstruction (PVO), preoperative ventilator support, or emergency surgery were reported. The sutureless technique group enrolled seven patients with a median age of 12 days (interquartile range, 5–16 days) and a median weight of 3.04 kg (interquartile range, 2.76–3.20 kg). In this group, two patients with preoperative PVO, four patients with preoperative ventilator support, and seven patients requiring emergency operation were found. The semisutureless technique group enrolled nine patients with a median age of 14 days (interquartile range, 7–24 days) and a median weight of 3.22 kg (interquartile range, 3.15–3.50 kg). In this group, four patients with preoperative PVO, two patients with preoperative ventilator support, and seven patients requiring emergency operation were noted.ResultsIn the conventional surgery group, two patients with postoperative supraventricular tachycardia, one patient with postoperative low cardiac output syndrome, one patient with PVO, and no case of postoperative death were reported. In the sutureless technique group, two patients with postoperative low cardiac output syndrome, one patient with postoperative supraventricular tachycardia, one patient with postoperative PVO, and no postoperative deaths were determined. In the semisutureless technique group, three patients had low cardiac output syndrome, two patients had supraventricular tachycardia after the operation, and one patient, who had been admitted to the hospital after cardiopulmonary resuscitation in the emergency room, died early after the operation. No case of death or PVO was noted after the operation.ConclusionThe semisutureless technique has positive effects. This surgery method can enlarge the anastomotic stoma, increase the volume of the left atrium, reduce the tension of the anastomotic stoma, fix the pulmonary vein to avoid distortion, and prevent postoperative hemorrhage.

Objective: In order to explore the effect of an external electrostatic field on the growth of ice crystals during food freezing. Methods: Based on the classic Kobayashi model of phase field method, the free energy density of electric field was introduced into the phase field model. Used the five-point difference scheme in the finite difference method to discretize the partial differential equation, the simulation and visualization of ice crystal growth were realized by programming. Results: The results showed that the simulation results were consistent with other simulation results and experimental results, and the ice crystal morphology had a typical sixfold symmetry; With the increase of electric field intensity, the growth rate of main branches and nucleation growth of ice crystals were inhibited. Conclusion: In the process of quick-frozen food preservation, adding a certain electric field strength will reduce the formation of ice crystals, and retain the quality and flavor of food as much as possible.

Dilated cardiomyopathy (DCM) is one of the leading causes of heart failure in children with diverse clinical characteristics. To date, DCM with a giant atrium as the first manifestation is rare and has not been reported in previous literature. We report a case of a male infant born with a significantly enlarged right atrium. Due to worsened clinical symptoms and the risk of arrhythmias and thrombosis, we performed the surgical reduction of the right atrium. Unfortunately, DCM and a progressive re-enlargement of the right atrium appeared during midterm follow-up. The mother's echocardiogram also suggested DCM, and the patient was eventually considered for a diagnosis of familial DCM. This case may expand the clinical spectrum of DCM and reminds us of the importance of good follow-up of children with idiopathic dilatation of the right atrium.