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Quantum geometry - the geometry of electron Bloch wavefunctions - is central to modern condensed matter physics. Due to the quantum nature, quantum geometry has two parts, the real part quantum metric and the imaginary part Berry curvature. The studies of Berry curvature have led to countless breakthroughs, ranging from the quantum Hall effect in 2DEGs to the anomalous Hall effect (AHE) in ferromagnets. However, in contrast to Berry curvature, the quantum metric has rarely been explored. Here, we report a new nonlinear Hall effect induced by quantum metric by interfacing even-layered MnBi2Te4 (a PT-symmetric antiferromagnet (AFM)) with black phosphorus. This novel nonlinear Hall effect switches direction upon reversing the AFM spins and exhibits distinct scaling that suggests a non-dissipative nature. Like the AHE brought Berry curvature under the spotlight, our results open the door to discovering quantum metric responses. Moreover, we demonstrate that the AFM can harvest wireless electromagnetic energy via the new nonlinear Hall effect, therefore enabling intriguing applications that bridges nonlinear electronics with AFM spintronics., Just appeared in Science. Originally submitted to Science on Oct. 5, 2022

Recent experiments have observed large anisotropic collective flows in high multiplicity proton-lead collisions at the Large Hadron Collider (LHC), which indicates the possible formation of mini quark-gluon plasma (QGP) in small collision systems. However, no jet quenching has been confirmed in such small systems so far. To understand this intriguing result, the system size scan experiments have been proposed to bridge the gap between large and small systems. In this work, we perform a systematic study on both heavy and light flavor jet quenching in different collision systems at the LHC energies. Using our state-of-the-art jet quenching model, which combines the next-to-leading-order perturbative QCD framework, a linear Boltzmann transport model and the (3+1)-dimensional viscous hydrodynamics simulation, we provide a good description of nuclear modification factor $R_{\rm AA}$ for charged hadrons and $D$ mesons in central and mid-central Pb+Pb and Xe+Xe collisions measured by CMS collaboration. We further predict the transverse momentum and centrality dependences of $R_{AA}$ for charged hadrons, $D$ and $B$ mesons in Pb+Pb, Xe+Xe, Ar+Ar and O+O collisions at the LHC energies. Our numerical results show a clear system size dependence for both light and heavy flavor hadron $R_{AA}$ across different collision systems. Sizable jet quenching effect is obtained for both heavy and light flavor hadrons in central O+O collisions at the LHC energies. Our study provides a significant bridge for jet quenching from large to small systems, and should be helpful for finding the smallest QGP droplet and the disappearance of QGP in relativistic nuclear collisions., Comment: 12 pages, 8 figures

To systemically evaluate the clinical efficacy and safety of Hongjin Xiaojie Capsules for hyperplastic disease of breast(HDBA), so as to provide the evidence for its clinical application. The inclusion criteria are the RCT of single administration of Hongjin Xiaojie Capsules for treatment of HDBA. We retrieved following databases(CNKI, WanFang, VIP, SinoMed, Cochrane Library and PubMed) from their inception to October 1, 2019. Two researchers independently screened out literatures and extracted data, and assessed the methodological quality of eligible RCT according to the criteria in Cochrane Handbook for Systematic Reviews of Interventions. RevMan 5.3 was used for data analysis, binary data was summarized by risk ratio(RR) with confidence intervals(CI) of 95%, and continuous data were summarized by mean difference(MD) with CI of 95%. To estimate the sample size of systematic review, trial sequential analysis(TSA) was performed base on software TSA v0.9 version. Totally 14 RCTs were included, involving 3 057 patients. The results of Meta-analysis showed a significantly higher cure rate(RR=1.13, 95%CI[1.03, 1.25], P=0.01) and higher total effective rate(RR=1.09, 95%CI[1.05, 1.13], Plt;0.000 1) in Hongjin Xiaojie Capsules group than those in the Juyuansuan Tamoxifen group. The incidence of adverse events was significantly higher in Juyuansuan Tamoxifen group than that in Hongjin Xiaojie Capsules group(RR=0.28 95%CI[0.16, 0.49], Plt;0.001), and the adverse events included nausea, vomiting, abdominal pain, diarrhea, irregular menstruation, amenorrhea, unclear vision, dizziness and headache. The TSA for the cure rate demonstrated that the current available data reached the expected value. However, due to the low effect intensity of evidence, the pooled results might be affected by high risk bias of trials. The quality of evidence of included trials was generally low or very low. Inverted funnel diagram showed possible publication bias. This review suggested that Hongjin Xiaojie Capsules were potentially effective and safe in treatment of HDBA, especially, the incidences of drug-related adverse events from Hongjin Xiaojie Capsules were significantly lower than those from tamoxifen. However, because of lack of high-quality evidence for drawing a conclusion, more rigorously designed and high-quality trials are needed to confirm the efficacy and safety of Hongjin Xiaojie Capsules.

To explore the surgical methods and clinical effect of endoscopic endonasal approaches for the treatment of invasive pituitary adenomas (IPAs).A retrospective analysis was made of the clinical data of 74 patients (75 procedures) with IPAs treated by different endoscopic endonasal approaches at the Department of Neurosurgery, The First Affiliated Hospital of Shenzhen University from May 2014 to August 2017. The data include clinical manifestation, imaging features, surgical methods and complications, resection rate, cure rate, prognosis, and complications in different Knosp classifications and Hardy stages. The transcavernous approach was used in 47 patients, the lateral-cavernous approach was used in 14 patients, the tuberculum sella planum approach was used in 8 patients, and the diaphragma sellae open or dorsum sellae cut approach was used in 6 patients.The gross total resection (GTR) rate was 70.7% (53 patients) and tumor residue rate was 29.3% (22 patients). GTR rate for pituitary adenoma according to Knosp classification was 89.3% in grade 3 and 28.6% in grade 4. The biology cure rate was 75.0% and 23.8%, respectively. There was significance between them (P 0.05). In addition, the GTR rate of Hardy stage was 90.5% in stage C, 90.0% in stage D, 26.1% in stage E, and the biology cure rate was 80.1%, 75.0%, and 13.0%, respectively. There was significance among them (P 0.05) Postoperative severe complications included 9 patients (12.0%) with cerebrospinal fluid leaks, 26 patients (34.7%)with electrolyte imbalance, 36 patients (48.0%) with transient diabetes insipidus, 22 patients (29.3%) with hypopituitarism, 2 patients (2.7%) with permanent hypopituitarism, and 2 patients (2.7%)with epistaxis. The follow-up lasted 2-41 months (average, 19.3 months). No patient experienced recurrence after GTR, 1 patient undergoing subtotal experienced recurrence and underwent reoperation, 3 patients underwent postoperative Gamma Knife treatment, and 2 patients with refractory IPA were given temozolomide and metformin chemotherapy.According to the invasiveness of IPA, choosing the appropriate endoscopic surgical approach is helpful in removing tumors and reducing complications.

The most prominent advantage of the solar sail is no propellant. The thrust is continuous, small and the direction is limited by the attitude. To get the time-optimal interplanetary transfer trajectory, an optimal control model for the transfer mission is provided with the characteristic of solar sail. In the dynamic model, the force is just the gravity in the Earth influence sphere, and in the heliocentric coordinates the forces are the solar gravitation and the solar radiation pressure force. The co state initial value normalization method are proposed to avoid the problem of initial value sensitivity. The exhaustion method is used for optimal the targets and sequence. A filter method of tree structure uses the preset thresholds to reduce the computation load. At last, an orbit with flight time 6.78 years is selected and the attitude angular velocity of the huge solar sail is less than 7deg/day.

In researching the problems of stochastic system, we usually use the linearization method, the approximate decoupling method, and the truncated method etc. to simplify the system model. The traditional criterion is the ratio of the simplification part and the initial model. If the ratio is small enough or the model errors can be regarded as noise, we think the simplification method is reasonable. The shortage of the criterion is that it hasn't a very definite value or bound, and it can't combine the performance of the whole system. Therefore we propose a new criterion which calculates the errors and error covariance matrix of the state between the initial system and the simplified system based on Kalman filter. The new criterion judges the trace of the matrix and its convergence property. Because it uses the state equation and the measurement equation of the stochastic system, it is more suitable for the whole system performance.

Checking the observability is important. It is a way to evaluate the feasibility of the system such that the measurement set can enable reliable state estimation[1]. In this paper, the concept of local observability is introduced for nonlinear systems. Here two kinds of method to check the observability of a deep-space autonomous navigation system are used: an analytical method and a computational method. The first method takes partial derivative of the measurement. The observability matrix is used to determining local observability in the other method. The condition number of the matrix is adopted as a scalar measure of degree of local observability. At last we give the observability results of an interplanetary spacecraft navigation system.