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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 work opens up opportunities for exploring topological vacua and related long-sought-after instantons in tabletop experiments.

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 wavefunctions. 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 non-vanished., Comment: 12 pages, 9 figures

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.

We proposed a scheme to manipulate the single qubit as the superposition of two atomic ground states in a large detuned three level Λ system using double fractional stimulated Raman adiabatic passages. This single qubit evolves mainly through two high efficient passages: a dark passage and a bright passage. Then we show the demonstration of witnessing the model independent quantumness with properly designed laser sequence according to the real experiment system of cold 87Rb atomic ensemble. Finally, we discuss the effects of dephasing, laser noise and detection noise on the quantumness witness through numerical simulations.

We propose a practical scheme to implement universal superadiabatic geometric quantum gates in decoherence-free subspaces in the trapped-ions system. The logical qubit is only encoded by two neighboring physical qubits, which is the minimal resource for the decoherence-free subspace encoding. Different from the nonadiabatic control in decoherence-free subspace (Liang et al. in Phys Rev A 89:062312, 2014), a new Hamiltonian to implement universal effective interaction between logical qubits is proposed in the scheme. The proposed gates are numerically demonstrated to be robust against both systematic errors and collective dephasing noises, which combine the advantages of superadiabatic geometric quantum control and decoherence-free subspace. Since the Hamiltonian we use relies solely on two-body interactions, our scheme would be promising to be realized experimentally in trapped-ions systems.

To investigate the clinical effects of aripiprazole on sexual dysfunction induced by amisulpride or risperidone in male patients with schizophrenia.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.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, P0.05) and T level (［13.3 ± 2.7］ vs ［17.4±3.0］ mmol/L, P0.05) but a decreased level of PRL (［38.5 ± 10.5］ vs ［27.9 ± 8.2］ ng/ml, P0.05). 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 (P0.05). 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, P0.05) and even lower at 8 weeks (51.2 ± 5.2) (P0.05). 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.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.目的： 探讨阿立哌唑治疗氨磺必利或利培酮致男性精神分裂症患者性功能障碍的临床疗效。方法： 2014年10月至2016年10月收治的75例经氨磺必利或利培酮治疗后继发性功能障碍的首发精神分裂症患者为研究对象，采用交叉换药法2周内停服氨磺必利或利培酮，并逐渐增加阿立哌唑口服剂量至20～30 mg/d，第3周开始30 mg/d维持，记录阿立哌唑换药前、治疗4、8周后患者者性功能、催乳素（PRL）、睾酮(T)、阳性和阴性症状量表评分(PANSS)变化及药物不良反应。结果： 75例患者改服阿立哌唑4周，患者性功能总评分［（32.6±3.6)分 vs (24.3±2.1）分］、T［（17.4±3.0)）mmol/L vs (13.3±2.7）mmol/L］均较换药前明显上升（P均0.05），PRL［（27.9±8.2) ng/ml vs (38.5±10.5） ng/ml］显著下降（P0.05）；治疗8周，患者性欲评分、T、PRL均已恢复至入院时基线水平，性功能评分中勃起评分、射精评分、性满意度评分、总评分及T数值已超过基线水平，但差异均无统计学意义（P0.05）。改服阿立哌唑4周后，患者PANSS评分均较换药前显著下降［（57.2±5.5)分 vs (62.1 ±4.9）分，P0.05］；治疗8周后PANSS评分显著低于治疗4周后评分［（51.2±5.2)分 vs (57.2±5.5）分，P0.05］。改服阿立哌唑后，兴奋、头晕、失眠、食欲减退的发生率分别为6.7%、5.3%、4.0%、1.3%，未见其他严重不良发应。 结论： 阿立哌唑治疗男性精神分裂症合并药源性性功能障碍，能在继续改善阳性与阴性症状的同时，改善患者性功能，恢复生殖激素水平。.

Realization of the highly efficient $\ensuremath{\pi}$ and $\ensuremath{\pi}/2$ pulses is crucial in an atom interferometry. Here we propose a scheme to realize these operations based on an intrinsically fault-tolerant geometric phase and stimulated Raman shortcuts to the adiabatic passage. The scheme is fast due to the shortcuts to adiabaticity and is robust based on the geometric phase. In the presence of various noises, we show that the fringe contrast of the proposed interferometer is higher than that of the resonant Raman pulse and the stimulated Raman adiabatic passage. Furthermore, the scheme is demonstrated to be especially suitable for applications that require a large space-time area enclosed by interfering wave packets.

We demonstrate a long-coherent-time coupling between microwave and optical fields through cold atomic ensembles. The phase information of the microwave field is stored in a coherent superposition state of a cold atomic ensemble and is then read out by two optical fields after 12 ms. A similar operation of mapping the phase of optical fields into a cold atomic ensemble and then retrieving by microwave is also demonstrated. These studies demonstrate that long-coherent-time cold atomic ensembles could resonantly couple with microwave and optical fields simultaneously, which paves the way for realizing high-efficiency, high-bandwidth, and noiseless atomic quantum converters.

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 to prepare 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. We here 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., 8 pages, 5 figures, comments and suggestion are welcome

We propose a feasible scheme to implement a universal set of quantum gates based on geometric phases and superadiabatic quantum control. Consolidating the advantages of both strategies, the proposed quantum gates are robust and fast. The diamond nitrogen-vacancy center system is adopted as a typical example to illustrate the scheme. We show that these gates can be realized in a simple two-level configuration by appropriately controlling the amplitude, phase, and frequency of just one microwave field. The gate's robust and fast features are confirmed by comparing the fidelity of the proposed superadiabatic geometric phase (controlled-PHASE) gate with those of two other kinds of phase (controlled-PHASE) gates., Comment: 6 pages, 2 figures

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 KCI 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 KCI 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.

Implementing nonadiabatic holonomic quantum computation in decoherence-free subspaces may consolidate the advantages of both strategies and thus leads to suppression of both local and collective noises. In a recent paper, Xu et al. [Phys. Rev. Lett. 109, 170501 (2012)] proposed an interesting implementation of such a scheme; however, four-body interaction, which is hard to achieve in a realistic system, is required there. In this paper we propose a simplified scheme to implement such single-qubit and two-qubit logical operations by utilizing only two-body interactions, which is much easier to realize in a trapped ion system.

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.Kv1.3 channels were expressed in xenopus oocytes, and currents were measured using the two-microelectrode voltage-clamp technique.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).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.

To evaluate significance of different reperfusion methods in the treatment of acute ST segment elevation myocardial infarction (STEMI).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.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 (P0.05). The incidence of cardiac events including unstable angina, complex ventricular arrhythmia, and cardiac insufficiency were not significantly different between the 3 groups (P0.05), nor was Killip class, number of Q waves on ECG, wall motion score, left ventricular ejection fraction, cardiac index, or stroke volume index (P0.05).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.

To identify the factors related to acute ST-segment elevation myocardial infarction (STEMI) with normal angiographic findings of the coronary artery.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.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 (P0.05), whereas multiple logistic regression analysis identified the former 3 factors as the related factors (P0.05). 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 (P0.01).Acute STEMI with normal coronary artery is more likely to occur in young smokers without pre-infarction angina, possibly in association with spontaneous reperfusion.