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The ability to realize high-fidelity quantum communication is one of the many facets required to build generic quantum computing devices. In addition to quantum processing, sensing, and storage, transferring the resulting quantum states demands a careful design that finds no parallel in classical communication. Existing experimental demonstrations of quantum information transfer in solid-state quantum systems are largely confined to small chains with few qubits, often relying upon non-generic schemes. Here, by using a superconducting quantum circuit featuring thirty-six tunable qubits, accompanied by general optimization procedures deeply rooted in overcoming quantum chaotic behavior, we demonstrate a scalable protocol for transferring few-particle quantum states in a two-dimensional quantum network. These include single-qubit excitation, two-qubit entangled states, and two excitations for which many-body effects are present. Our approach, combined with the quantum circuit's versatility, paves the way to short-distance quantum communication for connecting distributed quantum processors or registers, even if hampered by inherent imperfections in actual quantum devices.
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Blueberries are highly perishable after harvest, so a simple preservation method is needed to extend the shelf life of blueberries. In this study, sodium chlorite-loaded sepiolite was added to polylactide solution with tartaric acid to create a ClO2 gas slow-release fresh-keeping card. The fresh-keeping card absorbs moisture in the air, which causes tartaric acid to enter the sepiolite and react with sodium chlorite to release ClO2 gas slowly. The study investigated the impact of fresh-keeping cards on the quality attributes of blueberries, including appearance, decay rate, ethylene release rate, respiration rate, hardness, ascorbic acid content, and anthocyanin concentration. Low-field nuclear magnetic technology was used to analyze the water state and distribution of blueberries during storage. The results showed that the ClO2 gas released by the fresh-keeping card can destroy ethylene in the air and kill microorganisms in blueberries, thereby delaying fruit decay.
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Cloretos , Compostos Clorados , Cloro , Conservação de Alimentos , Silicatos de Magnésio , Poliésteres , Tartaratos , Conservação de Alimentos/métodos , Óxidos , EtilenosRESUMO
Emerging quantum technologies hold the promise of unravelling difficult problems ranging from condensed matter to high-energy physics while, at the same time, motivating the search for unprecedented phenomena in their setting. Here, we use a custom-built superconducting qubit ladder to realize non-thermalizing states with rich entanglement structures in the middle of the energy spectrum. Despite effectively forming an "infinite" temperature ensemble, these states robustly encode quantum information far from equilibrium, as we demonstrate by measuring the fidelity and entanglement entropy in the quench dynamics of the ladder. Our approach harnesses the recently proposed type of non-ergodic behavior known as "rainbow scar," which allows us to obtain analytically exact eigenfunctions whose ergodicity-breaking properties can be conveniently controlled by randomizing the couplings of the model without affecting their energy. The on-demand tunability of quantum correlations via disorder allows for in situ control over ergodicity breaking, and it provides a knob for designing exotic many-body states that defy thermalization.
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BACKGROUND: Drowning is the leading cause of death for children under the age of 15 years in Guangdong Province, China. This serious public health issue also exists in low- and middle-income countries (LMICs), which have few value-integrated intervention programs. The current study presents an integrated intervention project that aims to explore an effective pattern of prevention for child drowning in rural areas and feasibility to perform in other LMICs. METHODS: We conducted a cluster randomized controlled trial by comparing the incidence of non-fatal drowning among children in two groups in rural areas of southern China. We recruited the participants in two phases and reached a total of 10 687 students from 23 schools at two towns in Guangdong Province, China. At the first and second phases, 8966 and 1721 students were recruited, respectively. RESULTS: The final evaluation questionnaires were collected after 18 months of integrated intervention, where we obtained 9791 data from Grades 3-9. The incidence of non-fatal drowning between the intervention and control groups after intervention did not differ significantly from the baseline according to the total number of students, male students, female students and Grades 6-9 [0.81; 95% confidence interval (CI): [0.66, 1.00]; p = 0.05, 1.17; 95% CI: [0.90, 1.51]; p = 0.25, 1.40; 95% CI: [0.97, 2.02]; p = 0.07 and 0.97; 95% CI: [0.70, 1.34]; p = 0.86], except for Grades 3-5 (1.36; 95% CI: [1.02, 1.82]; p = 0.037). The study observed a significantly positive benefit of awareness and risk behaviours of non-fatal drowning between the intervention and control groups (0.27, 95% CI: [0.21, 0.33]; p = 0.00, -0.16; 95% CI: [-0.24, -0.08]; p = 0.00). CONCLUSIONS: The integrated intervention exerted a significant impact on the prevention and management of child non-fatal drowning, especially in rural areas.
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Afogamento Iminente , Prática de Saúde Pública , Adolescente , Criança , Feminino , Humanos , Masculino , China/epidemiologia , Afogamento/prevenção & controle , Saúde Pública/estatística & dados numéricos , Estudantes/estatística & dados numéricos , Inquéritos e Questionários , População Rural/estatística & dados numéricos , Estudos de Viabilidade , Prática de Saúde Pública/estatística & dados numéricos , Afogamento Iminente/prevenção & controleRESUMO
Topological photonics provides a powerful platform to explore topological physics beyond traditional electronic materials and shows promising applications in light transport and lasers. Classical degrees of freedom are routinely used to construct topological light modes in real or synthetic dimensions. Beyond the classical topology, the inherent quantum nature of light provides a wealth of fundamentally distinct topological states. Here we implement experiments on topological states of quantized light in a superconducting circuit, with which one- and two-dimensional Fock-state lattices are constructed. We realize rich topological physics including topological zero-energy states of the Su-Schrieffer-Heeger model, strain-induced pseudo-Landau levels, valley Hall effect, and Haldane chiral edge currents. Our study extends the topological states of light to the quantum regime, bridging topological phases of condensed-matter physics with circuit quantum electrodynamics, and offers a freedom in controlling the quantum states of multiple resonators.
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Quantum many-body systems away from equilibrium host a rich variety of exotic phenomena that are forbidden by equilibrium thermodynamics. A prominent example is that of discrete time crystals1-8, in which time-translational symmetry is spontaneously broken in periodically driven systems. Pioneering experiments have observed signatures of time crystalline phases with trapped ions9,10, solid-state spin systems11-15, ultracold atoms16,17 and superconducting qubits18-20. Here we report the observation of a distinct type of non-equilibrium state of matter, Floquet symmetry-protected topological phases, which are implemented through digital quantum simulation with an array of programmable superconducting qubits. We observe robust long-lived temporal correlations and subharmonic temporal response for the edge spins over up to 40 driving cycles using a circuit of depth exceeding 240 and acting on 26 qubits. We demonstrate that the subharmonic response is independent of the initial state, and experimentally map out a phase boundary between the Floquet symmetry-protected topological and thermal phases. Our results establish a versatile digital simulation approach to exploring exotic non-equilibrium phases of matter with current noisy intermediate-scale quantum processors21.
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Quantum computing promises to enhance machine learning and artificial intelligence. However, recent theoretical works show that, similar to traditional classifiers based on deep classical neural networks, quantum classifiers would suffer from adversarial perturbations as well. Here we report an experimental demonstration of quantum adversarial learning with programmable superconducting qubits. We train quantum classifiers, which are built on variational quantum circuits consisting of ten transmon qubits featuring average lifetimes of 150 µs, and average fidelities of simultaneous single- and two-qubit gates above 99.94% and 99.4%, respectively, with both real-life images (for example, medical magnetic resonance imaging scans) and quantum data. We demonstrate that these well-trained classifiers (with testing accuracy up to 99%) can be practically deceived by small adversarial perturbations, whereas an adversarial training process would substantially enhance their robustness to such perturbations.
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Inteligência Artificial , Metodologias Computacionais , Teoria Quântica , Aprendizado de Máquina , Redes Neurais de ComputaçãoRESUMO
Polydopamine (PDA) has been gradually applied in wound healing of various types in the last three years. Due to its rich phenol groups and unique structure, it can be combined with a variety of materials to form wound dressings that can be used for chronic infection, tissue repair in vivo and serious wound healing. PDA complex has excellent mechanical properties and self-healing properties, and it is a stable material that can be used for a long period of time. Unlike other dressings, PDA complexes can achieve both photothermal therapy and electro activity. In this paper, wound healing is divided into four stages: antibacterial, anti-inflammatory, cell adhesion and proliferation, and re-epithelialization. Photothermal therapy can improve the bacteriostatic rate and remove reactive oxygen species to inhibit inflammation. Electrical signals can stimulate cell proliferation and directional migration. With low reactive oxygen species (ROS) levels, inflammatory factors are down-regulated and growth factors are up-regulated, forming regular collagen fibers and accelerating wound healing. Finally, five potential development directions are proposed, including increasing drug loading capacity, optimization of drug delivery platforms, improvement of photothermal conversion efficiency, intelligent electroactive materials and combined 3D printing.
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Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Bandagens , Indóis/farmacologia , Polímeros/farmacologia , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/química , Anti-Inflamatórios/química , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Indóis/química , Estrutura Molecular , Polímeros/químicaRESUMO
Preparation of ternary nanoparticles using high amylose complex, stearic acid, and soy protein isolate as shell materials and their encapsulation of curcumin were studied. The effect of curcumin in ternary nanostructures, loading capacity of the nanoparticles, its solubility and sustained release behavior in vitro are discussed. The encapsulation efficiency of the ternary nanoparticles was 87.14 ± 0.70%, and the loading rate was 16.81 µg/g. Qualitative analysis showed that curcumin addition increases the long-range and short-range ordered structure of ternary starch (TS) by changing its crystallinity. Fourier transform infrared spectroscopy showed that curcumin-TS is formed via hydrogen bonds and hydrophobic properties of the protein. An in vitro release test showed that TS particles can control the stable release of curcumin in simulated intestinal fluid. Our study provided a novel approach to high biomass encapsulation and sustained release of polyphenols.
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Curcumina/administração & dosagem , Curcumina/química , Portadores de Fármacos/química , Ácidos Graxos/química , Nanopartículas/química , Proteínas de Soja/química , Amido/química , Sistemas de Liberação de Medicamentos , Liberação Controlada de Fármacos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios XRESUMO
In this paper, the effects of an aging treatment on the corrosion resistance/mechanism of a tensile deformed Al-Cu-Mn-Fe-Zr alloy are investigated. The impedance magnitude and polarization resistance increase, while the corrosion current decreases with the increased aging time and temperature. The discontinuously-distributed precipitates and precipitation-free zone, which can cut the corrosion channels, appear at grain boundaries when the temperature is relatively high and the aging time is relatively long. They can improve the corrosion resistance. Additionally, the intergranular and pitting corrosion are the main mechanisms. The intergranular corrosion is likely to occur in an under-aged alloy. This is because the potential difference between the grain boundaries and grains is high, due to the segregation of Cu atoms. When the aging degree is increased, the grain boundary precipitates reduce the potential difference, and the intragranular precipitates make the surrounding matrix prone to dissolution. As such, the pitting corrosion is likely to occur in the over-aged alloys.
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Deformation behavior and precipitation features of an Al-Cu alloy are investigated using uniaxial tensile tests at intermediate temperatures. It is found that the true stress drops with the decreased strain rate or the increased deformation temperature. The number of substructures and the degree of grain elongation decrease with the raised temperature or the decreased strain rate. At high temperatures or low strain rates, some dynamic recrystallized grains can be found. The type of precipitates is influenced by the heating process before hot tensile deformation. The content and size of precipitates increase during tensile deformation at intermediate temperatures. As the temperature increases over 200 °C, the precipitation process (Guinier Preston zone (G.P. zones)âθ'' phaseâθ' phase) is enhanced, resulting in increased contents of θ'' and θ' phases. However, θ'' and θ' phases prefer to precipitate along the {020}Al direction, resulting in an uneven distribution of phases. Considering the flow softening degree and the excessive heterogeneous precipitation of θ'' and θ' phases during hot deformation, the reasonable strain rate and temperature are about 0.0003 s-1 and 150 °C, respectively.
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OBJECTIVES: Previous studies have used latent profile analysis (LPA) to examine rural left-behind children's anxiety. Further study is needed to identify the heterogeneous characteristics of rural left-behind children's anxiety and explore the related factors. SETTING: A cross-sectional survey using a school-based sample was conducted in January 2018 in Qingxin district, Qingyuan city, Guangdong province. PARTICIPANTS: 1026 left-behind children (effective response rate of the questionnaire: 95.39%). MAIN OUTCOME MEASURES: Profile latent classes (LC) and anxiety disorder. RESULTS: The LPA identified three anxiety LC: 'low anxiety' (56.6%), 'medium anxiety' (34.8%) and 'severe anxiety' (8.6%). The multinomial logistic regression model was used to predict the relationship between personal, family, school factors and anxiety. We found that the variables directly related to lower anxiety classes included age (12-14 years), harmonious or fair relationship with classmates, no neglect, harmonious parental relationship and the duration of mother migration <6 months. CONCLUSIONS: These findings suggested the need for careful consideration of differences in anxieties among rural left-behind children. Identifying latent subgroups may provide an empirical basis for teachers and public health practitioners to implement anxiety intervention efforts.
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Transtornos de Ansiedade/epidemiologia , Adolescente , Fatores Etários , Transtornos de Ansiedade/etiologia , Criança , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , População Rural , Fatores Sexuais , MigrantesRESUMO
BACKGROUND: Drowning is a leading cause of accidental death in children under 14 years of age in Guangdong, China. We developed a statistical model to classify the risk of drowning among children based on the risk factors. METHODS: A multiple-stage cluster random sampling was employed to select the students in Grades 3 to 9 in two townships in Qingyuan, Guangdong. Questionnaire was a self-reported measure consisting of general information, knowledge, attitudes and activities. A univariate logistic regression model was used to preliminarily select the independent variables at a P value of 0.1 for multivariable model. Three-quarters of the participants were randomly selected as a training sample to establish the model, and the remaining were treated as a testing sample to validate the model. RESULTS: A total of 8390 children were included in this study, about 12.18% (1013) experienced drowning during the past one year. In the univariate logistic regression model, introvert personality, unclear distributions of water areas on the way to school, and bad relationships with their classmates and families were positively associated with drowning. However, females, older age and lower swimming skills were negatively associated with drowning. After employing the prediction model with these factors to estimate drowning risk of the students in the testing samples, the results of Hosmer-Lemeshow tests showed non-significant differences between the predictive results and actual risk (χ2 = 5.97, P = 0.65). CONCLUSIONS: Male, younger children, higher swimming skills, bad relationship with their classmates and families, introvert personality and unclear distributions of water areas on the way to school were important risk factors of non-fatal drowning among children. The prediction model based on these variables has an acceptable predictive ability.