Efficient Initialization of Fluxonium Qubits based on Auxiliary Energy Levels.

Fast and high-fidelity qubit initialization is crucial for low-frequency qubits such as fluxonium, and in applications of many quantum algorithms and quantum error correction codes. In a circuit quantum electrodynamics system, the initialization is typically achieved by transferring the state between the qubit and a short-lived cavity through microwave driving, also known as the sideband cooling process in atomic system. Constrained by the selection rules from the parity symmetry of the wave functions, the sideband transitions are only enabled by multiphoton processes which require multitone or strong driving. Leveraging the flux tunability of fluxonium, we circumvent this limitation by breaking flux symmetry to enable an interaction between a noncomputational qubit transition and the cavity excitation. With single-tone sideband driving, we realize qubit initialization with a fidelity exceeding 99% within a duration of 300 ns, robust against the variation of control parameters. Furthermore, we show that our initialization scheme has a built-in benefit in simultaneously removing the second-excited state population of the qubit, and can be easily incorporated into a large-scale fluxonium processor.

Native Approach to Controlled-Z Gates in Inductively Coupled Fluxonium Qubits.

The fluxonium qubits have emerged as a promising platform for gate-based quantum information processing. However, their extraordinary protection against charge fluctuations comes at a cost: when coupled capacitively, the qubit-qubit interactions are restricted to XX interactions. Consequently, effective ZZ or XZ interactions are only constructed either by temporarily populating higher-energy states, or by exploiting perturbative effects under microwave driving. Instead, we propose and demonstrate an inductive coupling scheme, which offers a wide selection of native qubit-qubit interactions for fluxonium. In particular, we leverage a built-in, flux-controlled ZZ interaction to perform qubit entanglement. To combat the increased flux-noise-induced dephasing away from the flux-insensitive position, we use a continuous version of the dynamical decoupling scheme to perform noise filtering. Combining these, we demonstrate a 20 ns controlled-z gate with a mean fidelity of 99.53%. More than confirming the efficacy of our gate scheme, this high-fidelity result also reveals a promising but rarely explored parameter space uniquely suitable for gate operations between fluxonium qubits.

Quantum Instruction Set Design for Performance.

A quantum instruction set is where quantum hardware and software meet. We develop characterization and compilation techniques for non-Clifford gates to accurately evaluate its designs. Applying these techniques to our fluxonium processor, we show that replacing the iSWAP gate by its square root SQiSW leads to a significant performance boost at almost no cost. More precisely, on SQiSW we measure a gate fidelity of up to 99.72% and averaging at 99.31%, and realize Haar random two-qubit gates with an average fidelity of 96.38%. This is an average error reduction of 41% for the former and a 50% reduction for the latter compared to using iSWAP on the same processor.

Rare Case of Paraneoplastic Pemphigus Associated With Prostatic Cancer.

ABSTRACT: The combination of paraneoplastic pemphigus and prostate cancer is extremely unusual and has not been reported yet. Paraneoplastic pemphigus is caused by tumor-induced autoantibodies, which cause damage to the skin and mucosa. The essential treatment is active tumor control. Our patient received a robot-assisted radical prostatectomy and glucocorticoid therapy to improve his condition and relieve his skin lesions.

Fluxonium: An Alternative Qubit Platform for High-Fidelity Operations.

Superconducting qubits provide a promising path toward building large-scale quantum computers. The simple and robust transmon qubit has been the leading platform, achieving multiple milestones. However, fault-tolerant quantum computing calls for qubit operations at error rates significantly lower than those exhibited in the state of the art. Consequently, alternative superconducting qubits with better error protection have attracted increasing interest. Among them, fluxonium is a particularly promising candidate, featuring large anharmonicity and long coherence times. Here, we engineer a fluxonium-based quantum processor that integrates high qubit coherence, fast frequency tunability, and individual-qubit addressability for reset, readout, and gates. With simple and fast gate schemes, we achieve an average single-qubit gate fidelity of 99.97% and a two-qubit gate fidelity of up to 99.72%. This performance is comparable to the highest values reported in the literature of superconducting circuits. Thus our work, within the realm of superconducting qubits, reveals an alternative qubit platform that is competitive with the transmon system.

Ultrahigh Kinetic Inductance Superconducting Materials from Spinodal Decomposition.

Disordered superconducting nitrides with kinetic inductance have long been considered to be leading material candidates for high-inductance quantum-circuit applications. Despite continuing efforts toward reducing material dimensions to increase the kinetic inductance and the corresponding circuit impedance, achieving further improvements without compromising material quality has become a fundamental challenge. To this end, a method to drastically increase the kinetic inductance of superconducting materials via spinodal decomposition while maintaining a low microwave loss is proposed. Epitaxial Ti0.48 Al0.52 N is used as a model system and the utilization of spinodal decomposition to trigger the insulator-to-superconductor transition with a drastically enhanced material disorder is demonstrated. The measured kinetic inductance increases by two to three orders of magnitude compared with the best disordered superconducting nitrides reported to date. This work paves the way for substantially enhancing and deterministically controlling the inductance for advanced superconducting quantum circuits.

Nanodrug regulates lactic acid metabolism to reprogram the immunosuppressive tumor microenvironment for enhanced cancer immunotherapy.

A majority of cancers fail to respond to immunotherapy due to the immunosuppressive tumor microenvironment (TME), and metabolic regulation of the TME has been a promising strategy to improve immunotherapy. Lactate is a key metabolic player in tumor immune response since its excess secretion aggravates tumor immune escape by favoring the polarization of tumor-associated macrophages (TAMs) to an immunosuppressive phenotype meanwhile impeding the tumor infiltration of the cytotoxic T lymphocyte. Here, we proposed a metabolic reprogramming mechanism to ameliorate tumor immunosuppression by using lonidamine and syrosingopine incorporated liposomes (L@S/L) to regulate lactate production and efflux. Concretely, lonidamine reduced lactate production by affecting the glycolytic metabolic pathway while syrosingopine decreased lactate efflux by inhibiting the key protein expression of the lactate transporter MCT-4. Consequently, both the drugs synergistically normalize the pH of the TME to overcome the tumor immunosuppressive microenvironment. In vivo studies demonstrated that the decreased extracellular lactate preferentially polarized TAMs to the M1 phenotype, simultaneously increased the proportion of NK cells and reduced the number of Treg cells. These results validated an efficient tumor immunotherapy in the breast cancer model. This new strategy of lactic acid metabolism regulation is proposed to operate in concert with immune modulation in the TME, which shows great potential for immunotherapy of immunologically "cold" tumors.

Knowledge Domain and Emerging Trends of Chinese Medicine in Management of Pediatric Asthma: A Scientometric Study / 中国结合医学杂志

OBJECTIVE@#To analyze the intellectual landscape and emerging research trends of Chinese medicine (CM) in the management of pediatric asthma through a scientometric study.@*METHODS@#Publications related to CM in the management of pediatric asthma were retrieved from the Web of Science Core Collection using relevant keywords. A scientometric study was performed using CiteSpace and VOSviewer.@*RESULTS@#A total of 1,673 original articles and reviews from 1991 to 2019 were included in the analysis. The amount of annual publications had a gradual increase with time. USA was the major contributor both in country and institution analyses. Based on the co-citation, the published journals were grouped into 4 clusters. Keyword analysis indicated that the main hotspots were: (1) comprehensive management; (2) risk factors, mechanism, and prevalence; (3) prevention and treatment; (4) inflammation; and (5) environmental research. Lastly, we predicted that three emerging trends were quality of life promotion, immune response, and combination therapy.@*CONCLUSIONS@#CM research in the management of pediatric asthma will maintain the current trend of steady growth. This scientometric analysis may help scientists to identify the areas of interests and future directions in the field.

Knowledge Domain and Emerging Trends of Chinese Medicine in Management of Pediatric Asthma: A Scientometric Study.

OBJECTIVE: To analyze the intellectual landscape and emerging research trends of Chinese medicine (CM) in the management of pediatric asthma through a scientometric study. METHODS: Publications related to CM in the management of pediatric asthma were retrieved from the Web of Science Core Collection using relevant keywords. A scientometric study was performed using CiteSpace and VOSviewer. RESULTS: A total of 1,673 original articles and reviews from 1991 to 2019 were included in the analysis. The amount of annual publications had a gradual increase with time. USA was the major contributor both in country and institution analyses. Based on the co-citation, the published journals were grouped into 4 clusters. Keyword analysis indicated that the main hotspots were: (1) comprehensive management; (2) risk factors, mechanism, and prevalence; (3) prevention and treatment; (4) inflammation; and (5) environmental research. Lastly, we predicted that three emerging trends were quality of life promotion, immune response, and combination therapy. CONCLUSIONS: CM research in the management of pediatric asthma will maintain the current trend of steady growth. This scientometric analysis may help scientists to identify the areas of interests and future directions in the field.

Effects of SPARCL1 on the proliferation and differentiation of sheep preadipocytes.

Important candidate genes that regulate lipid metabolism have the potential to increase the content of intramuscular fat (IMF) and improve meat quality. Secreted protein acidic and rich in cysteine like 1(SPARCL1) is a secreted glycoprotein with important physiological functions and is involved in the proliferation and differentiation of various cells. However, the role of the SPARCL1 gene in sheep preadipocytes and its regulatory mechanism is still unclear. In this study, we explored the effect of SPARCL1 on the proliferation and differentiation of sheep preadipocytes. The results showed that the expression level of the SPARCL1 gene is higher in fat tissue than in other tissues, and the gene was significantly increased on the 6th day of preadipocyte differentiation. In the preadipocyte proliferation stage, interference of SPARCL1 gene reduced cell viability and increased cell apoptosis. In preadipocyte differentiation stage, SPARCL1 overexpression significantly inhibited lipid droplets accumulation and triglyceride content by increasing Wnt10b, Fzd8, IL6, and ß-catenin and inhibiting PPARγ, C/EBPα, LPL, and IGF1 genes expression, whereas SPARCL1 deficiency significantly promoted cell differentiation by inhibiting ß-catenin and increasing GSK3ß, PPARγ, C/EBPα, and LPL. The results of this study suggest that SPARCL1 plays a negative role during preadipocyte differentiation and may become a novel target for regulating preadipocyte differentiation and improving IMF.Abbreviations:IMF: Intramuscular fat SPARCL1: Secreted protein acidic and rich in cysteine like 1 PPARγ: Peroxisome proliferator-activated receptor γ C/EBPα: CCAAT/enhancer-binding protein-α LPL: Lipoprotein lipase IGF1: Insulin-like growth factor 1 Wnt10b: Wnt family member 10B Fzd8: Frizzled class receptor 8 IL6: Interleukin 6 ß-catenin: Catenin beta interacting protein 1 GSK3ß: Glycogen synthase kinase 3 beta LRP5/6: Low-density lipoprotein receptor-related protein 5/6.