Steady motional entanglement between two distant levitated nanoparticles.

Quantum entanglement in macroscopic systems is not only essential for practical quantum information processing, but also valuable for the study of the boundary between quantum and the classical world. However, it is very challenging to achieve the steady remote entanglement between distant macroscopic systems. We consider two distant nanoparticles, both of which are optically trapped in two cavities. Based on the coherent scattering mechanism, we find that the ultrastrong optomechanical coupling between the cavity modes and the motion of the levitated nanoparticles could be achieved. The large and steady entanglement between the filtered output cavity modes and the motion of nanoparticles can be generated if the trapping laser is under the red sideband. Then through entanglement swapping, the steady motional entanglement between the distant nanoparticles can be realized. We numerically simulate and find that the two nanoparticles with 10 km distance can be entangled for the experimentally feasible parameters, even in room temperature environments. The generated continuous variable multipartite entanglement is the key to realizing the quantum enhanced sensor network and the sensitivity beyond the standard quantum limit.

Highly sensitive gyroscope based on a levitated nanodiamond.

A gyroscope is one of the core components of an inertial navigation system. Both the high sensitivity and miniaturization are important for the applications of the gyroscope. We consider a nitrogen-vacancy (NV) center in a nanodiamond, which is levitated either by an optical tweezer or an ion trap. Based on the Sagnac effect, we propose a scheme to measure the angular velocity with ultra-high sensitivity through the matter-wave interferometry of the nanodiamond. Both the decay of the motion of the center of mass of the nanodiamond and the dephasing of the NV centers are included when we estimate the sensitivity of the proposed gyroscope. We also calculate the visibility of the Ramsey fringes, which can be used for estimating the limitation of gyroscope sensitivity. It is found that the sensitivity ∼6.86×10-7 r a d/s/H z can be achieved in an ion trap. As the working area of the gyroscope is extremely small (∼0.01~µm2), it could be made on-chip in the future.

Unlocking the Recovery Potential: JMJD3 Inhibition-Mediated SAPK/JNK Signaling Inactivation Supports Endogenous Oligodendrocyte-Lineage Commitment Post Mammalian Spinal Cord Injury.

Spinal cord injury (SCI) induced catastrophic neurological disability is often incurable at present. The injury triggered immediately oligodendrocytes loss and overwhelming demyelination are regarded as an insurmountable barrier to SCI recovery. To date, effective strategy to promote the endogenous oligodendrocytes replacement post SCI remains elusive. Epigenetic modifications are emerging as critical molecular switches of gene expression in CNS. However, the epigenetic mechanisms underlying oligodendrogenesis post SCI yet to be discovered. In this study, we report that H3K27me3 demethylase JMJD3 exists as a pivotal epigenetic regulator which manipulates the endogenous oligodendrogenesis post SCI. We found that JMJD3 inhibition promotes the oligodendrocyte linage commitment of neural stem/progenitor cells (NPCs) in vitro and in vivo. Moreover, we demonstrated that JMJD3 inhibition mediated SAPK/JNK signaling inactivation is functionally necessary for endogenous oligodendrocyte-lineage commitment post SCI. Our results also suggested that JMJD3 is downstream of SAPK/JNK pathway, and capable of translates SCI induced SAPK/JNK signaling into epigenetic codes readable by spinal cord endogenous NPCs. Taken together, our findings provide novel evidence of JMJD3 mediated oligodendrocyte-lineage commitment orchestration post SCI, which would be a potential epigenetic approach to induce the mature mammalian endogenous recovery.

Mast cell activation, TLR4-NF-κB/TNF-α pathway variation in rats' intestinal ischemia-reperfusion injury and Tongxinluo's therapeutic effect.

This study was designed to investigate mast cell activation and related TLR4-NF-κB/TNF-α pathway variation in 3 and 7 days' rats intestinal I/R injury, and TXL's intervention effect. Rat intestine I/R injury was carried out using superior mesenteric artery occlusion model with 30 min ischemia followed 3 or 7 days' reperfusion. Rats were administered TXL ultrafine power of 0.4, 0.8 and 1.6g/kg/d respectively for 3 or 7 days after modeling. Mast cell activation was determined by immunofluorescent double staining. TLR4, ANGPTL4 and microRNA126 were determined by RT-PCR. PECAM-1, NF-κB p65, TNF-α and VE-Cadherin were determined by immunohistochemical staining. Intestine I/R induced massively mast cell activation and overexpressed TLR4, NF-κB, TNF-α, PECAM-1, miR126 in 3 and 7 days. VE-cadherin and ANGPTL4 expression was reduced. TXL treatment attenuated mast cell activation and inhibited TLR4, NF-κB, TNF-α, PECAM-1 over-expression in 3 and 7 days, protected VE-cadherin and ANGPTL4 protein. Inflammation boomed in rats' intestine I/R injury for 3 and 7 days, characterized by mast cell and related TLR4-NF-κB/TNF-α pathway activation, accompanied with endothelial barrier dysfunction and enhanced vascular permeability. TXL treatment attenuated inflammation, protected endothelial barrier function. TXL treat intestine I/R injury, according with "Treat different diseases with the same method" in TCM theory.

Observation of Topological Magnon Insulator States in a Superconducting Circuit.

Searching topological states in artificial systems has recently become a rapidly growing field of research. Meanwhile, significant experimental progress on observing topological phenomena has been made in superconducting circuits. However, topological insulator states have not yet been reported in this system. Here, for the first time, we experimentally realize a tunable dimerized spin chain model and observe the topological magnon insulator states in a superconducting qubit chain. Via parametric modulations of the qubit frequencies, we show that the qubit chain can be flexibly tuned into topologically trivial or nontrivial magnon insulator states. Based on monitoring the quantum dynamics of a single-qubit excitation in the chain, we not only measure the topological winding numbers, but also observe the topological magnon edge and defect states. Our experiment exhibits the great potential of tunable superconducting qubit chain as a versatile platform for exploring noninteracting and interacting symmetry-protected topological states.

High-precision gravimeter based on a nano-mechanical resonator hybrid with an electron spin.

We show that the gravitational acceleration can be measured with the matter-wave Ramsey interferometry, by using a nitrogen-vacancy center coupled to a nano-mechanical resonator. We propose two experimental methods to realize the similar Hamiltonian, by using either a cantilever resonator or a trapped nanoparticle. The scheme is robust against the thermal noise, and could be realized at the temperature much higher than the quantum regime. The effects of decoherence on the interferometry fringe visibility is calculated, considering both the mechanical motional decay and dephasing of the nitrogen-vacancy center. In addition, we demonstrate that under the various sources of random and systematic noises, our gravimeter can be made on-chip and achieve a high measurement of precision. Under experimental feasible parameters, the proposed gravimeter could achieve 10-10 relative precision.

Sensitivity of displacement detection for a particle levitated in the doughnut beam.

Displacement detection of a spherical particle in focused laser beams with a quadrant photodetector provides a fast and high precision way to determine the particle location. In contrast to the traditional Gaussian beams, the sensitivity of displacement detection using various doughnut beams is investigated. The sensitivity improvement for large spherical particles along the longitudinal direction is reported. With appropriate vortex charge l of the doughnut beams, they can outperform the Gaussian beam to get more than one order of magnitude higher sensitivity and, thus, have potential applications in various high-precision measurements. By using the levitating doughnut beam to detect the particle displacement, the result will also facilitate the recent proposal of levitating a particle in doughnut beams to suppress the light absorption.

Single phonon source based on a giant polariton nonlinear effect.

We propose a single phonon source based on nitrogen-vacancy (NV) centers, which are located in a diamond phononic crystal resonator. The strain in the lattice would induce the coupling between the NV centers and the phonon mode. The strong coupling between the excited state of the NV centers and the phonon is realized by adding an optical laser driving. This four-level NV center system exhibits coherent population trapping and yields giant resonantly enhanced acoustic nonlinearities, with zero linear susceptibility. Based on this nonlinearity, the single phonon source can be realized. We numerically calculate g(2)(0) of the single phonon source. We discuss the effects of the thermal noise and the external driving strength.

Single-Loop Realization of Arbitrary Nonadiabatic Holonomic Single-Qubit Quantum Gates in a Superconducting Circuit.

Geometric phases are noise resilient, and thus provide a robust way towards high-fidelity quantum manipulation. Here we experimentally demonstrate arbitrary nonadiabatic holonomic single-qubit quantum gates for both a superconducting transmon qubit and a microwave cavity in a single-loop way. In both cases, an auxiliary state is utilized, and two resonant microwave drives are simultaneously applied with well-controlled but varying amplitudes and phases for the arbitrariness of the gate. The resulting gates on the transmon qubit achieve a fidelity of 0.996 characterized by randomized benchmarking and the ones on the cavity show an averaged fidelity of 0.978 based on a full quantum process tomography. In principle, a nontrivial two-qubit holonomic gate between the qubit and the cavity can also be realized based on our presented experimental scheme. Our experiment thus paves the way towards practical nonadiabatic holonomic quantum manipulation with both qubits and cavities in a superconducting circuit.

Quantum memory and non-demolition measurement of single phonon state with nitrogen-vacancy centers ensemble.

In a diamond, the mechanical vibration-induced strain can lead to interaction between the mechanical mode and the nitrogen-vacancy (NV) centers. In this work, we propose to utilize the strain-induced coupling for the quantum non-demolition (QND) single phonon measurement and memory in a diamond. The single phonon in a diamond mechanical resonator can be perfectly absorbed and emitted by the NV centers ensemble (NVE) with adiabatically tuning the microwave driving. An optical laser drives the NVE to the excited states, which have much larger coupling strength to the mechanical mode. By adiabatically eliminating the excited states under large detuning limit, the effective coupling between the mechanical mode and the NVE can be used for QND measurement of the single phonon state. Under realistic experimental conditions, we numerically simulate the scheme. It is found that the fidelity of the absorbing and emitting process can reach a much high value. The overlap between the input and the output phonon shapes can reach 98.57%.

Torsional Optomechanics of a Levitated Nonspherical Nanoparticle.

An optically levitated nanoparticle in vacuum is a paradigm optomechanical system for sensing and studying macroscopic quantum mechanics. While its center-of-mass motion has been investigated intensively, its torsional vibration has only been studied theoretically in limited cases. Here we report the first experimental observation of the torsional vibration of an optically levitated nonspherical nanoparticle in vacuum. We achieve this by utilizing the coupling between the spin angular momentum of photons and the torsional vibration of a nonspherical nanoparticle whose polarizability is a tensor. The torsional vibration frequency can be 1 order of magnitude higher than its center-of-mass motion frequency, which is promising for ground state cooling. We propose a simple yet novel scheme to achieve ground state cooling of its torsional vibration with a linearly polarized Gaussian cavity mode. A levitated nonspherical nanoparticle in vacuum will also be an ultrasensitive nanoscale torsion balance with a torque detection sensitivity on the order of 10^{-29} N m/sqrt[Hz] under realistic conditions.

Low back pain tied to spinal endometriosis.

STUDY DESIGN: Case report. OBJECTIVE: We present a case of endometriosis of lumbar vertebrae. The literatures are reviewed with endometriosis of spine. Endometriosis is a common condition, which is defined as endometrial tissue lying outside the endometrial cavity. It is usually found within the peritoneal cavity, predominantly within the pelvis, commonly on the uterosacral ligaments. It can also be found in other sites such as umbilicus, abdominal scars, nasal passages and pleural cavity. But it is very rarely seen in the spine, with no report of endometriosis found in the lumbar vertebrae. METHOD: A 33-year-old woman presented with severe low back pain. She had the low back pain periodically for 3 years, and the pain was associated with menstruation. Radiographs showed a lesion in the posterior L3 body. After surgery, tissue biopsy indicated the presence of endometrial tissue in the lesion and thus confirmed endometriosis. RESULTS: Most cases of spine endometriosis that have been reported are usually found inside spinal canal, endorachis or spinal cord. But spinal vertebrae can also be involved in endometriosis. CONCLUSIONS: Although endometriosis is a rare possible cause of periodical low back pain in women of childbearing age, we suggest that if a woman suffering from periodical low back pain is encountered, do not ignore the possibility of endometriosis in the spine.

Levitated optomechanics: From single to many-body physics.

The levitated optomechanics, because of its ultra-high mechanical Q > 1010, is considered to be one of the best testbeds for macroscopic quantum superpostions. In this perspective, we give a brief review on the development of the levitated optomechanics, focusing on the macroscopic quantum phenomena, and the applications in quantum precision measurement. The levitated nanodiamond with built-in nitrogen-vacancy centers is discussed as an example. Finally, we discuss the future dirctions of the levtated optomechanics, such as the space-based experiments, the arrays of levitated optomechanics and applications in quantum simulation.

Space-time crystals of trapped ions.

Spontaneous symmetry breaking can lead to the formation of time crystals, as well as spatial crystals. Here we propose a space-time crystal of trapped ions and a method to realize it experimentally by confining ions in a ring-shaped trapping potential with a static magnetic field. The ions spontaneously form a spatial ring crystal due to Coulomb repulsion. This ion crystal can rotate persistently at the lowest quantum energy state in magnetic fields with fractional fluxes. The persistent rotation of trapped ions produces the temporal order, leading to the formation of a space-time crystal. We show that these space-time crystals are robust for direct experimental observation. We also study the effects of finite temperatures on the persistent rotation. The proposed space-time crystals of trapped ions provide a new dimension for exploring many-body physics and emerging properties of matter.

Characteristics of bloodstream infection and initial antibiotic use in critically ill burn patients and their impact on patient prognosis.

To investigate the bacterial epidemiology of blood cultures taken during the treatment of critically ill burn patients, the use of antibiotics at admission and before the observation of positive blood cultures, and their effect on prognosis. A retrospective study method was used. From January 1, 2010, to December 31, 2019, burn patients who met the inclusion criteria and were treated at the Burn Department, Ruijin Hospital, Shanghai Jiaotong University School of Medicine, were enrolled in the study. Data were collected from the patients' electronic medical records. General patient information, including length of hospital stay, length of intensive care unit (ICU) stay, in-hospital mortality, the bacteria epidemiological characteristics of blood cultures, and the use of antibiotics within 24 h after admission and before a positive blood culture was observed, was collected. Independent sample t tests and χ2 tests were used to compare the effects of a positive blood culture and the use of appropriate antibiotics within 24 h after admission and before the observation of a positive blood culture on prognosis. (1) The three most frequently detected bacteria in the blood cultures were Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii, and the amount of K. pneumoniae detected increased gradually. (2) Compared with the group of patients who were negative for bloodstream infection , the positive bloodstream infection group had a larger total body burn surface area (TBSA) (t = - 5.097, P = 0.000) and third-degree burn area (t = - 5.133, P = 0.000), a significantly longer length of hospital stay (t = 3.003, P = 0.003) and the length of ICU stay (t = 4.258, P = 0.000), and a significantly higher rate of in-hospital mortality (χ2 = 8.485, P = 0.004). When K. pneumoniae was detected, the length of hospital stay (t = 2.148, P = 0.035) and the length of ICU stay (t = 2.880, P = 0.005) were significantly prolonged. (3) The two antibiotics that were most frequently used in patients with acute burns within 24 h after admission were lincomycin (90 cases, 29.32%) and carbapenems (79 cases, 25.73%). Comparing the clinical characteristics of the lincomycin group and the carbapenem group, the TBSA (t = - 3.34, P = 0.001) and the third-degree burn area (t = - 6.08, P = 0.000) of the patients in the carbapenem group were larger, and the length of hospital stay (t = - 2.136, P = 0.035) and length of ICU stay (t = - 5.18, P = 0.000) were longer, but the difference in in-hospital mortality was not statistically significant (χ2 = 1.983, P = 0.159). (4) Comparing the group with appropriate initial antibiotic use within 24 h of admission to the inappropriate use group, the TBSA (t = - 0.605, P = 0.547), the third-degree burn area (t = 0.348, P = 0.729), the length of hospital stay (t = - 0.767, P = 0.445), the length of ICU stay (t = - 0.220, P = 0.827) and in-hospital mortality (χ2 = 1.271, P = 0.260) were not significantly different. (5) Comparing the group with appropriate antibiotic use before a positive blood culture was observed to the group with inappropriate antibiotic use, the TBSA (t = - 0.418, P = 0.677), the third-degree burn area (t = 0.266, P = 0.791), the length of hospital stay, the length of ICU stay (t = 0.995, P = 0.322) and in-hospital mortality (χ2 = 1.274, P = 0.259) were not significantly different. We found that patients with a positive blood culture had a larger burn area and a worse prognosis; that the greater the amount of K. pneumoniae in the bloodstream of burn patients was, the longer the hospital and ICU stays were; that whether appropriate antibiotics were administered to acute critical burn patients 24 h after admission had no effect on the prognosis; and that whether appropriate antibiotics were administered before a positive blood culture was observed had no effect on prognosis.

Revisiting the immune landscape post spinal cord injury: More than black and white.

Spinal cord injury (SCI) induced catastrophic neurological disability is currently incurable, especially in elderly patients. Due to the limited axon regeneration capacity and hostile microenvironment in the lesion site, essential neural network reconstruction remains challenging. Owing to the blood-spinal cord barrier (BSCB) created immune cells and cytokines isolation, the immune elements were incorrectly recognized as innocent bystanders during the SCI pathological process traditionally. Emerging evidence demonstrated that the central nervous system (CNS) is an "immunological quiescent" rather than "immune privileged" area, and the CNS-associated immune response played mixed roles which dedicate beneficial and detrimental contributions throughout the SCI process. Consequently, coordinating double-edged immunomodulation is vital to promote tissue repair and neurological recovery post-SCI. The comprehensive exploration and understanding of the immune landscape post-SCI are essential in establishing new avenues for further basic and clinical studies. In this context, this review summarizes the recent significant breakthroughs in key aspects of SCI-related immunomodulation, including innate and adaptive immune response, immune organ changes, and holistic immune status modification. Moreover, the currently existing immune-oriented therapies for SCI will be outlined.

Fecal Microbiota Transplantation Controls Progression of Experimental Autoimmune Hepatitis in Mice by Modulating the TFR/TFH Immune Imbalance and Intestinal Microbiota Composition.

Intestinal microbiota (IM) dysbiosis contributes to the development of autoimmune hepatitis (AIH). This study aimed to investigate the potential effect of fecal microbiota transplantation (FMT) in a murine model of experimental AIH (EAH), a condition more similar to that of AIH patients. Changes in the enteric microbiome were determined in AIH patients and EAH mice. Moreover, we established an experimental model of secondary EAH mice harboring dysbiosis (ABx) to analyze the effects of therapeutic FMT administration on follicular regulatory T (TFR) and helper T (TFH) cell imbalances and IM composition in vivo. Alterations of the IM composition and bacterial translocation occurred in AIH patients compared to nonalcoholic fatty liver disease patients and healthy controls (HCs). Therapeutic FMT significantly attenuated liver injury and bacterial translocation and improved the imbalance between splenic TFR cells and TFH cells in ABx EAH mice. Furthermore, therapeutic FMT also partially reversed the increasing trend in serum liver enzymes (ALT and AST) of CXCR5-/-EAH mice on the 28th day. Finally, therapeutic FMT could effectively restore antibiotic-induced IM dysbiosis in EAH mice. Taken together, our findings demonstrated that FMT was capable of controlling hepatitis progression in EAH mice, and the associated mechanism might be involved in the regulation of the TFR/TFH immune imbalance and the restoration of IM composition.

Testing a quantum error-correcting code on various platforms.

Quantum error correction plays an important role in fault-tolerant quantum information processing. It is usually difficult to experimentally realize quantum error correction, as it requires multiple qubits and quantum gates with high fidelity. Here we propose a simple quantum error-correcting code for the detected amplitude damping channel. The code requires only two qubits. We implement the encoding, the channel, and the recovery on an optical platform, the IBM Q System, and a nuclear magnetic resonance system. For all of these systems, the error correction advantage appears when the damping rate exceeds some threshold. We compare the features of these quantum information processing systems used and demonstrate the advantage of quantum error correction on current quantum computing platforms.

Endoscopic submucosal dissection of coexisting early esophageal carcinoma and leiomyoma: a case report and review of the literature.

The occurrence of early esophageal cancer located within an area of leiomyoma is extremely rare, and its clinical features and treatment methods have not been well described. We herein report the clinical characteristics, diagnosis, and treatment methods of early esophageal cancer that developed on top of a leiomyoma in the upper third of the esophagus in a 78-year-old woman. All tumor marker concentrations were normal. The leiomyoma was correctly diagnosed as a submucosal tumor by endoscopy and endoscopic ultrasonography. Endoscopic biopsy revealed esophageal squamous cell carcinoma. Both lesions were successfully treated by endoscopic submucosal dissection. The patient was followed up for 6 months without recurrence. Endoscopic submucosal dissection was a successful initial treatment method for esophageal carcinoma coexisting with esophageal leiomyoma in this case.

The first complete chloroplast genome of the fern genus Polystichum (Dryopteridaceae).

The first chloroplast genome of the fern genus Polystichum Roth (Dryopteridaceae) is reported here. Polystichum deltodon (Baker) Diels belongs to subgenus Haplopolystichum (Polystichum; Dryopteridaceae), many species of which are endangered or critically endangered species. The complete chloroplast genome of P. deltodon was determined for the first time in this work, which is revealed a circle quadripartite structure of 154,143 bp in length comprising a large single-copy region (LSC) of 86,990 bp, a small single-copy region (SSC) of 21,593 bp and a pair of inverted regions (IRs) of 22,780 bp, respectively. Based on the reported chloroplast genomes of Dryopteridaceae, phylogenetic analyses suggested that P. deltodon was located nearly to the genus Crytomium, which is in agreement with previous systematic research.