Synthetic Landau levels and spinor vortex matter on Haldane spherical surface with magnetic monopole

We present a flexible scheme to realize exact flat Landau levels on curved spherical geometry in a system of spinful cold atoms. This is achieved by Floquet engineering of a magnetic quadrupole field. We show that a synthetic monopole field in real space can be created. We prove that the system can be exactly mapped to the electron-monopole system on sphere, thus realizing Haldane's spherical geometry for fractional quantum Hall physics. The scheme works for either bosons or fermions. We investigate the ground state vortex pattern for an $s$-wave interacting atomic condensate by mapping this system to the classical Thompson's problem. We further study the distortion and stability of the vortex pattern when dipolar interaction is present. Our scheme is compatible with current experimental setup, and may serve as a promising route of investigating quantum Hall physics and exotic spinor vortex matter on curved space.Comment: 11 pages, 4 figure

PIV flow measurements for a rotating square smooth channel heated by basically uniform heat flux

This document is the Accepted Manuscript of the following article: Ruquan You, Haiwang Li, Hongwei Wu, and Zhi Tao, ‘PIV flow measurements for a rotating square smooth channel heated by basically uniform heat flux’, International Journal of Heat and Mass Transfer, Vol. 119: 236-246, April 2018. Under embargo until 22 December 2018. The final, definitive version is available online at DOI: https://doi.org/10.1016/j.ijheatmasstransfer.2017.11.073, published by Elsevier Ltd.In this paper, we experimentally investigated the mainstream and secondary flow in a smooth rotating channel with wall heated by particle image velocimetry (PIV). The hybrid effect of Coriolis force and buoyancy force on the mainstream and secondary flow was taken into consideration in the current work. In the experiments, the Reynolds number, based on the channel hydraulic diameter (D = 80 mm) and the bulk mainstream velocity (Vm = 1.82 m/s), is 10,000, and the rotation numbers are 0, 0.13, 0.26, 0.39, respectively. Constant heat flux on the four channel walls are provided by Indium Tin Oxide (ITO) heater glass, the density ratio (d.r.) equaling approximately 0.1. The buoyancy number ranges from 0 to 0.153. The results showed that Coriolis force and buoyancy force have important influences on the flow field in rotating channels. Coriolis force pushes the mainstream to trailing side, making an asymmetry of the mainstream. On the cross-section, there is a symmetric two-vortex pair caused by the Coriolis. The two-vortex pair is pushed into the trailing side with the increase of rotation numbers. Then, there are two small vortex appearing near the leading side. Buoyancy force suppresses mainstream and causes the separation of the flow near the leading side. When the separated flow happened, the structure of secondary flow is disordered near the leading side.Peer reviewedFinal Accepted Versio

Search for light dark matter from atmosphere in PandaX-4T

We report a search for light dark matter produced through the cascading decay of $\eta$ mesons, which are created as a result of inelastic collisions between cosmic rays and Earth's atmosphere. We introduce a new and general framework, publicly accessible, designed to address boosted dark matter specifically, with which a full and dedicated simulation including both elastic and quasi-elastic processes of Earth attenuation effect on the dark matter particles arriving at the detector is performed. In the PandaX-4T commissioning data of 0.63 tonne$\cdot$year exposure, no significant excess over background is observed. The first constraints on the interaction between light dark matter generated in the atmosphere and nucleus through a light scalar mediator are obtained. The lowest excluded cross-section is set at $5.9 \times 10^{-37}{\rm cm^2}$ for dark matter mass of $0.1$ MeV$/c^2$ and mediator mass of 300 MeV$/c^2$. The lowest upper limit of $\eta$ to dark matter decay branching ratio is $1.6 \times 10^{-7}$

A Search for Light Fermionic Dark Matter Absorption on Electrons in PandaX-4T

We report a search on a sub-MeV fermionic dark matter absorbed by electrons with an outgoing active neutrino using the 0.63 tonne-year exposure collected by PandaX-4T liquid xenon experiment. No significant signals are observed over the expected background. The data are interpreted into limits to the effective couplings between such dark matter and electrons. For axial-vector or vector interactions, our sensitivity is competitive in comparison to existing astrophysical bounds on the decay of such dark matter into photon final states. In particular, we present the first direct detection limits for an axial-vector (vector) interaction which are the strongest in the mass range from 25 to 45 (35 to 50) keV/c$^2$

The evaluation and significance of cerebrovascular reactivity during perioperative period of neurosurgery

DOI：10.3969/j.issn.1672-6731.2011.02.02

Comparison of airway anatomical indices in magnetic resonance imaging between growth hormone pituitary adenoma and nonfunctioning pituitary adenoma

Objective To evaluate the application of airway anatomical indices in magnetic resonance imaging (MRI) to predict difficult airways in patients with growth hormone pituitary adenoma. Methods This is a retrospective analysis for patients with pituitary adenoma excision under general anesthesia at Beijing Tiantan Hospital, Capital Medical University, from December 2018 to December 2022. Patients with growth hormone pituitary adenoma (GH group, n=81) and patients with nonfunctioning pituitary adenoma (NF group, n=81) were included. Linear distance between upper lip and uvula (ULUD), tongue thickness on the plane of cervical vertebra 2/3 (TTC2/3), linear distance of supraglottic airway cervical vertebra 2/3(SADC2/3) and linear distance between underlip and posterior pharyngeal wall (ULPD) were measured in the median sagittal plane of head MRI. The data in the two groups were compared. Results ULUD, TTC2/3, and ULPD in the GH group were significantly longer than those in the NF group (P＜0.05). SADC2/3 was not significantly different (P＞0.05). GH was confirmed to be correlated with TTC2/3 and ULPD. Conclusions ULUD, TTC2/3, ULPD found by head MRI and GH can be used as predictors of difficult airway in patients with growth hormone pituitary adenoma

Midazolam Sedation Induces Upper Limb Coordination Deficits That Are Reversed by Flumazenil in Patients with Eloquent Area Gliomas.

BackgroundMidazolam has been found to exacerbate or unmask limb motor dysfunction in patients with brain tumors. This study aimed to determine whether the exacerbated upper limb motor-sensory deficits are mediated through benzodiazepine sites by demonstrating reversibility by flumazenil in patients with gliomas in eloquent areas.MethodsThis was an interventional, parallel assignment, nonrandomized trial. Study subjects were admitted in the operating room. Patients with supratentorial eloquent area gliomas and volunteers of similar age without neurologic disease were sedated with midazolam, but still responsive and cooperative. Motor and sensory functions for upper extremities were evaluated by the Nine-Hole Peg Test before and after midazolam, as well as after flumazenil reversal.ResultsThirty-two cases were included: 15 in the glioma group and 17 in the control group. The total dose of midazolam and flumazenil were comparable between the groups. In the glioma group, the times to task completion after midazolam in the contralateral hand (P = 0.001) and ipsilateral hand (P = 0.002) were 26.5 (95% CI, 11.3 to 41.7) and 13.7 (95% CI, 5.0 to 22.4) seconds slower than baseline, respectively. After flumazenil reversal, the contralateral hand (P = 0.99) and ipsilateral hand (P = 0.187) performed 1.2 (95% CI, -3.3 to 5.8) and 1.5 (95% CI, -0.5 to 3.5) seconds slower than baseline, respectively. In the control group, the dominant (P < 0.001) and nondominant hand (P = 0.006) were 2.9 (95% CI, 1.4 to 4.3) and 1.7 (95% CI, 0.5 to 2.9) seconds slower than baseline, respectively. After flumazenil, the dominant hand (P = 0.99) and nondominant hand (P = 0.019) performed 0.2 (95% CI, -0.7 to 1.0) and 1.3 (95% CI, -0.2 to 2.4) seconds faster than baseline, respectively.ConclusionsIn patients with eloquent area gliomas, mild sedation with midazolam induced motor coordination deficits in upper limbs. This deficit was almost completely reversed by the benzodiazepine antagonist flumazenil, suggesting that this is a reversible abnormality linked to occupation of the receptor by midazolam

Driving pressure-guided ventilation improves homogeneity in lung gas distribution for gynecological laparoscopy: a randomized controlled trial

Abstract To investigate whether driving pressure–guided ventilation could contribute to a more homogeneous distribution in the lung for gynecological laparoscopy. Chinese patients were randomized, after pneumoperitoneum, to receive either positive end expiratory pressure (PEEP) of 5 cm H2O (control group), or individualized PEEP producing the lowest driving pressure (titration group). Ventilation homogeneity is quantified as the global inhomogeneity (GI) index based on electrical impedance tomography, with a lower index implying more homogeneous ventilation. The perioperative arterial oxygenation index and respiratory system mechanics were also recorded. Blood samples were collected for lung injury biomarkers including interleukin-10, neutrophil elastase, and Clara Cell protein-16. A total of 48 patients were included for analysis. We observed a significant increase in the GI index immediately after tracheal extubation compared to preinduction in the control group (p = 0.040) but not in the titration group (p = 0.279). Furthermore, the GI index was obviously lower in the titration group than in the control group [0.390 (0.066) vs 0.460 (0.074), p = 0.0012]. The oxygenation index and respiratory compliance were significantly higher in the titration group than in the control group. No significant differences in biomarkers or hemodynamics were detected between the two groups. Driving pressure–guided PEEP led to more homogeneous ventilation, as well as improved gas exchange and respiratory compliance for patients undergoing gynecological laparoscopy. Trial Registration: ClinicalTrials.gov NCT04374162; first registration on 05/05/2020