Ultrahigh-Precision Hamiltonian Parameter Estimation in a Superconducting Circuit.

The Hamiltonian, which determines the evolution of a quantum system, is fundamental in quantum physics. Therefore, it is crucial to implement high-precision generation and measurement of the Hamiltonian in a practical quantum system. Here, we experimentally demonstrate ultrahigh-precision Hamiltonian parameter estimation with a significant quantum advantage in a superconducting circuit via sequential control. We first observe the commutation relation for noncommuting operations determined by the system Hamiltonian, both with and without adding quantum control, verifying the commuting property of controlled noncommuting operations. Based on this control-induced commuting property, we further demonstrate Hamiltonian parameter estimation for polar and azimuth angles in superconducting circuits, achieving ultrahigh metrological gains in measurement precision exceeding the standard quantum limit by up to 16.0 and 16.1 dB at N=100, respectively.

GPC3 and PEG10 peptides associated with placental gp96 elicit specific T cell immunity against hepatocellular carcinoma.

The placenta and tumors can exhibit a shared expression profile of proto-oncogenes. The basis of placenta-derived heat shock protein gp96, which induces prophylactic and therapeutic T cell responses against cancer including hepatocellular carcinoma (HCC), remains unknown. Here, we identified the associated long peptides from human placental gp96 using matrix-assisted laser desorption/ionization-time-of-flight and mass spectrometry and analyzed the achieved proteins through disease enrichment analysis. We found that placental gp96 binds to numerous peptides derived from 73 proteins that could be enriched in multiple cancer types. Epitope-harboring peptides from glypican 3 (GPC3) and paternally expressed gene 10 (PEG10) were the major antigens mediating anti-HCC T cell immunity. Molecular docking analysis showed that the GPC3- and PEG10-derived peptides, mainly obtained from the cytotrophoblast layer of the mature placenta, bind to the lumenal channel and client-bound domain of the gp96 dimer. Immunization with bone marrow-derived dendritic cells pulsed with recombinant gp96-GPC3 or recombinant gp96-PEG10 peptide complex induced specific T cell responses, and T cell transfusion led to pronounced growth inhibition of HCC tumors in nude mice. We demonstrated that the chaperone gp96 can capture antigenic peptides as an efficient approach for defining tumor rejection oncoantigens in the placenta and provide a basis for developing GPC3 and PEG10 peptide-based vaccines against HCC. This study provides insight into the underlying mechanism of the antitumor response mediated by embryonic antigens from fetal tissues, and this will incite more studies to identify potential tumor rejection antigens from placenta.

Synthetic Topological Vacua of Yang-Mills Fields in Bose-Einstein Condensates.

Topological vacua are a family of degenerate ground states of Yang-Mills fields with zero field strength but nontrivial topological structures. They play a fundamental role in particle physics and quantum field theory, but have not yet been experimentally observed. Here we report the first theoretical proposal and experimental realization of synthetic topological vacua with a cloud of atomic Bose-Einstein condensates. Our setup provides a promising platform to demonstrate the fundamental concept that a vacuum, rather than being empty, has rich spatial structures. The Hamiltonian for the vacuum of topological number n=1 is synthesized and the related Hopf index is measured. The vacuum of topological number n=2 is also realized, and we find that vacua with different topological numbers have distinctive spin textures and Hopf links. Our Letter opens up opportunities for exploring topological vacua and related long-sought-after instantons in tabletop experiments.

Measurement of Spin Chern Numbers in Quantum Simulated Topological Insulators.

The topology of quantum systems has become a topic of great interest since the discovery of topological insulators. However, as a hallmark of the topological insulators, the spin Chern number has not yet been experimentally detected. The challenge to directly measure this topological invariant lies in the fact that this spin Chern number is defined based on artificially constructed wave functions. Here we experimentally mimic the celebrated Bernevig-Hughes-Zhang model with cold atoms, and then measure the spin Chern number with the linear response theory. We observe that, although the Chern number for each spin component is ill defined, the spin Chern number measured by their difference is still well defined when both energy and spin gaps are nonvanished.

Hybrid superconductor-atom quantum interface with Raman chirped shortcut to adiabatic passage.

Realization of the highly efficient hybrid atom-photon gates is vital to the quantum interface that integrates atoms and superconducting resonators. Here we propose a scheme to realize the hybrid state transfer and controlled-PHASE gate based on Raman chirped shortcut to adiabatic passage. The scheme is fast to protect the quantum state from the decoherence effects in the hybrid interface, as well as is robust due to the geometric phase. We show that this two-qubit gate is more resilient than the Raman pulse and Raman chirped adiabatic passage against the variations in the vacuum coupling strength and two-photon detuning. Its fast and robust features make it especially suitable for long-term storage and optical readout of superconducting qubits, and moreover, entanglement swapping between two disparate components.

[Aripiprazole for drug-induced sexual dysfunction in schizophrenic males].

OBJECTIVE: To investigate the clinical effects of aripiprazole on sexual dysfunction induced by amisulpride or risperidone in male patients with schizophrenia. METHODS: This study included 75 male patients with drug-induced secondary sexual dysfunction after treated with amisulpride or risperidone for first-episode schizophrenia between October 2014 and October 2016. We substituted aripiprazole for amisulpride or risperidone, gradually increased the dose from 10 to 30 mg/d within 2 weeks, and maintained 30 mg/d from the 3rd week. At 4 and 8 weeks after medication, we evaluated the sexual function of the patients, measured the levels of serum prolactin (PRL) and testosterone (T), obtained the scores of the Positive and Negative Symptoms Scale (PANSS), recorded adverse reactions, and compared the parameters with those before aripiprazole administration. RESULTS: Compared with pre-aripiprazole administration, the patients showed significant increases after 4 weeks of medication in the sexual function score (24.3 ± 2.1 vs 32.6 ± 3.6, P <0.05) and T level (ï¼»13.3 ± 2.7ï¼½ vs ï¼»17.4±3.0ï¼½ mmol/L, P <0.05) but a decreased level of PRL (ï¼»38.5 ± 10.5ï¼½ vs ï¼»27.9 ± 8.2ï¼½ ng/ml, P <0.05). At 8 weeks, the sexual function score and serum PRL were both restored to the baseline levels at admission, and the erectile function score, ejaculation score, total score, and serum T level even exceeded the baseline, though with no statistically significant differences (P >0.05). In comparison with pre-aripiprazole administration, the PANSS score was significantly decreased at 4 weeks after medication (62.1 ± 4.9 vs 57.2 ± 5.5, P <0.05) and even lower at 8 weeks (51.2 ± 5.2) (P <0.05). The incidence rates of medication-related excitation, dizziness, insomnia, and loss of appetite were 6.7%, 5.3%, 4.0% and 1.3% respectively, and no other serious adverse reactions were observed. CONCLUSIONS: Aripiprazole is effective for the treatment of drug-induced sexual dysfunction in schizophrenic men by continuously alleviating their positive and negative symptoms and meanwhile improving their sexual function and restoring their sexual hormone levels.

Cellular gp96 upregulates AFP expression by blocking NR5A2 SUMOylation and ubiquitination in hepatocellular carcinoma.

Alpha-fetoprotein (AFP) is the most widely used biomarker for the diagnosis of hepatocellular carcinoma (HCC). However, a substantial proportion of HCC patients have either normal or marginally increased AFP levels in serum, and the underlying mechanisms are not fully understood. In the present study, we provided in vitro and in vivo evidence that heat shock protein gp96 promoted AFP expression at the transcriptional level in HCC. NR5A2 was identified as a key transcription factor for the AFP gene, and its stability was enhanced by gp96. A further mechanistic study by co-immunoprecipitation, GST pull-down, and molecular docking showed gp96 and the SUMO E3 ligase RanBP2 competitively binding to NR5A2 at the sites spanning from aa 507 to aa 539. The binding of gp96 inhibited SUMOylation, ubiquitination, and subsequent degradation of NR5A2. In addition, clinical analysis of HCC patients indicated that gp96 expression in tumors was positively correlated with serum AFP levels. Therefore, our study uncovered a novel mechanism that gp96 regulates the stability of its client proteins by directly affecting their SUMOylation and ubiquitination. These findings will help in designing more accurate AFP-based HCC diagnosis and progression monitoring approaches.

Quantitative determination of the electron beam radiation dose for SARS-CoV-2 inactivation to decontaminate frozen food packaging.

The spread of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) from cold-chain foods to frontline workers poses a serious public health threat during the current global pandemic. There is an urgent need to design concise approaches for effective virus inactivation under different physicochemical conditions to reduce the risk of contagion through viral contaminated surfaces of cold-chain foods. By employing a time course of electron beam exposure to a high titer of SARS-CoV-2 at cold-chain temperatures, a radiation dose of 2 â€‹kGy was demonstrated to reduce the viral titer from 104.5 to 0 median tissue culture infectious dose (TCID50)/mL. Next, using human coronavirus OC43 (HCoV-OC43) as a suitable SARS-CoV-2 surrogate, 3 â€‹kGy of high-energy electron radiation was defined as the inactivation dose for a titer reduction of more than 4 log units on tested packaging materials. Furthermore, quantitative reverse transcription PCR (RT-qPCR) was used to test three viral genes, namely, E, N, and ORF1ab. There was a strong correlation between TCID50 and RT-qPCR for SARS-CoV-2 detection. However, RT-qPCR could not differentiate between the infectivity of the radiation-inactivated and nonirradiated control viruses. As the defined radiation dose for effective viral inactivation fell far below the upper safe dose limit for food processing, our results provide a basis for designing radiation-based approaches for the decontamination of SARS-CoV-2 in frozen food products. We further demonstrate that cell-based virus assays are essential to evaluate the SARS-CoV-2 inactivation efficiency for the decontaminating strategies.

Finding citations for PubMed: a large-scale comparison between five freely available bibliographic data sources.

As an important biomedical database, PubMed provides users with free access to abstracts of its documents. However, citations between these documents need to be collected from external data sources. Although previous studies have investigated the coverage of various data sources, the quality of citations is underexplored. In response, this study compares the coverage and citation quality of five freely available data sources on 30 million PubMed documents, including OpenCitations Index of CrossRef open DOI-to-DOI citations (COCI), Dimensions, Microsoft Academic Graph (MAG), National Institutes of Health's Open Citation Collection (NIH-OCC), and Semantic Scholar Open Research Corpus (S2ORC). Three gold standards and five metrics are introduced to evaluate the correctness and completeness of citations. Our results indicate that Dimensions is the most comprehensive data source that provides references for 62.4% of PubMed documents, outperforming the official NIH-OCC dataset (56.7%). Over 90% of citation links in other data sources can also be found in Dimensions. The coverage of MAG, COCI, and S2ORC is 59.6%, 34.7%, and 23.5%, respectively. Regarding the citation quality, Dimensions and NIH-OCC achieve the best overall results. Almost all data sources have a precision higher than 90%, but their recall is much lower. All databases have better performances on recent publications than earlier ones. Meanwhile, the gaps between different data sources have diminished for the documents published in recent years. This study provides evidence for researchers to choose suitable PubMed citation sources, which is also helpful for evaluating the citation quality of free bibliographic databases.

Experimental realization of stimulated Raman shortcut-to-adiabatic passage with cold atoms.

Accurate control of a quantum system is a fundamental requirement in many areas of modern science ranging from quantum information processing to high-precision measurements. A significantly important goal in quantum control is preparing a desired state as fast as possible, with sufficiently high fidelity allowed by available resources and experimental constraints. Stimulated Raman adiabatic passage (STIRAP) is a robust way to realize high-fidelity state transfer but it requires a sufficiently long operation time to satisfy the adiabatic criteria. Here we theoretically propose and then experimentally demonstrate a shortcut-to-adiabatic protocol to speed-up the STIRAP. By modifying the shapes of the Raman pulses, we experimentally realize a fast and high-fidelity stimulated Raman shortcut-to-adiabatic passage that is robust against control parameter variations. The all-optical, robust and fast protocol demonstrated here provides an efficient and practical way to control quantum systems.

[Analysis of misdiagnosis in 33 cases of aortic dissection].

OBJECTIVE: To compare the clinical characteristics, clinical course and laboratory findings of diagnosed and misdiagnosed cases of aortic dissection (AD). METHODS: The data of 33 cases of AD were collected for a retrospective review. All the patients underwent examination with X-ray and B-type ultrasound, and diagnosis of the suspected cases was further verified CT and magnetic resonance imaging according to the criteria of presence of false lumen or free valves. Diagnosis of AD was established in 18 of the 33 patients, including 14 male and 4 female patients aged from 20 to 79 years with a mean of 55.8+/-11.4 years. Misdiagnosis occurred in 15 patients including 12 male and 3 female patients aged 22-75 years with a mean of 56.2+/-10.8 years. RESULTS: No significant differences were found between the diagnosed and misdiagnosed groups in terms of age, sex, hypertension, coronary heart disease, chest pain, heart murmur, pericardial effusion, pleural effusion, average systolic and diastolic pressure, white blood cell count, creatine phosphokinase (CK) and its isoenzyme CK-MB, or De Bakey type III (P>0.05). Significant differences in peripheral large blood vessel murmur, asymmetric blood pressure of the arm and leg, ST segment variation, arrhythmia, and De Bakey types I and II were noted between the two groups (P<0.05). In cases misdiagnosed as acute coronary syndrome, ST segment variation, creatine kinase, arrhythmia, and white blood cell count were significantly different from those in cases of diagnosed as AD (P<0.01), but CPK-MB and cardiac troponin I were comparable. CONCLUSION: The initial symptoms, disease course, cardioelectrographic changes and creatine kinase of AD can be easily confused with those of acute coronary syndrome, and special attention should be given to their differentiation.

[Analysis of different reperfusion methods for acute ST segment elevation myocardial infarction].

OBJECTIVE: To evaluate significance of different reperfusion methods in the treatment of acute ST segment elevation myocardial infarction (STEMI). METHODS: A retrospective analysis of the clinical data of electrocardiography (ECG), echocardiogram, and angiography was conducted in 271 cases of STEMI treated in our hospital. Of these patients 31 were treated by primary percutaneous coronary intervention (PCI), and 44 by intravenous thrombolysis with urokinase, including 26 with thrombolytic treatment with concomitant PCI and 18 with rescue PCI. RESULTS: The patients receiving primary PCI, thrombolytic therapy along with PCI, and rescue PCI did not exhibit significant differences in age, sex, diabetes, hypertension, hyperlipidemia, smoking status, symptom onset to treatment time, or collateral circulation (P>0.05). The incidence of cardiac events including unstable angina, complex ventricular arrhythmia, and cardiac insufficiency were not significantly different between the 3 groups (P>0.05), nor was Killip class, number of Q waves on ECG, wall motion score, left ventricular ejection fraction, cardiac index, or stroke volume index (P>0.05). CONCLUSION: Combination of thrombolytic therapy and interventional therapy can be a safe and effective treatment of STEMI, and rescue PCI may benefit the improvement of the left ventricular function.

[Factors associated with acute ST-segment elevation myocardial infarction with normal angiographic findings of the coronary artery].

OBJECTIVE: To identify the factors related to acute ST-segment elevation myocardial infarction (STEMI) with normal angiographic findings of the coronary artery. METHODS: An retrospective analysis of the electrocardiographic, echocardiographic, and angiographic data of 271 STEMI cases was conducted. Of these patients, 29 had normal coronary artery by angiography and from the rest patients presenting abnormal angiographic findings of the coronary artery, 60 were randomly selected to serve as the control group. Multiple logistic regression analysis was performed to identify the independent factors related to acute STEMI with normal coronary artery by angiography. RESULTS: The incidence rate of STEMI with normal coronary artery was 10.7%. Univariate analysis showed that age, smoking, diabetes mellitus, absence of pre-infarction angina, and wall motion score were related to STEMI with normal coronary artery (P<0.05), whereas multiple logistic regression analysis identified the former 3 factors as the related factors (P<0.05). Wall motion score, left ventricular ejection fraction, cardiac index, and stroke volume index were higher, and cardiac events fewer in patients with normal coronary artery than in those with abnormal coronary artery (P<0.01). CONCLUSION: Acute STEMI with normal coronary artery is more likely to occur in young smokers without pre-infarction angina, possibly in association with spontaneous reperfusion.

[Changes of blood lipids in colorectal cancer patients with coronary heart disease and value of lipid-lowering therapy with statins].

OBJECTIVE: To investigate the changes of blood lipid in patients with colorectal cancer complicated by coronary heart disease (CHD) and the effect of lipid-lowering therapy with statins in these patients. METHODS: In 32 pathologically confirmed colorectal cancer patients with CHD, the concentrations of total cholesterol (TC), triglyceride (TG), high-density lipoprotein-cholesterol (HDL-C), low-density lipoprotein-cholesterol (LDL-C) and lipoprotein (a) (Lp(a)) were detected at the baseline, before and after the operation, and at 6 months of postoperative atorvastatin treatment. Thirty patients with TC over 5.70 mmol/L and established coronary artery disease served as the control group. RESULTS: TC, TG and LDL-C in the 30 control patients were significantly decreased after 6 months of 20 mg atorvastatin treatment, and even further decreased till 12 months (P<0.01), but no significant changes occurred in HDL-C and Lp(a). The baseline level of TC, TG, LDL-C and HDL-C were significantly decreased (P<0.01), while Lp(a) increased (P<0.05) in the 32 cancer patients with CHD. Continuing atorvastatin treatment further decreased TC, TG and LDL-C (P<0.05) and increased HDL-C (P<0.05) without affecting Lp(a). The cancer patients had significantly lower TC and LDL-C levels than the control group (P<0.05), but had significantly increased Lp(a) (P<0.05). Six months of atorvastatin treatment further decreased LDL-C and HDL-C in the cancer patients (P<0.05), while TC and Lp(a) had no significant changes. CONCLUSIONS: Increased Lp(a) in colorectal cancer patients can be associated with its anti-tumor effect. Alterations in the blood lipid profile raises a new issue concerning the safety of lipid-lowering therapy in colorectal cancer patients complicated by CHD.

High extracellular potassium ion concentration attenuates the blockade action of ketanserin on Kv1.3 channels expressed in xenopus oocytes.

BACKGROUND: Ketanserin (KT), a selective serotonin (5-HT) 2-receptor antagonist, reduces peripheral blood pressure by blocking the activation of peripheral 5-HT receptors. In this study electrophysiological method was used to investigate the effect of KT and potassium ion on Kv1.3 potassium channels and explore the role of blocker KT in the alteration of channel kinetics contributing to the potassium ion imbalances. METHODS: Kv1.3 channels were expressed in xenopus oocytes, and currents were measured using the two-microelectrode voltage-clamp technique. RESULTS: KCl made a left shift of activation and an inactivation curve of Kv1.3 current and accelerated the activation and inactivation time constant. High extracellular [K(+)] attenuated the blockade effect of KT on Kv1.3 channels. In the presence of KT and KCl the activation and inactivation time constants were not influenced significantly no matter what was administered first. KT did not significantly inhibit Kv1.3 current induced by tetraethylammonium (TEA). CONCLUSIONS: KT is a weak blocker of Kv1.3 channels at different concentrations of extracellular potassium and binds to the intracellular side of the channel pore. The inhibitor KT of ion channels is not fully effective in clinical use because of high [K(+)](o) and other electrolyte disorders.