Improvement of response bandwidth and sensitivity of Rydberg Receiver using multi-channel excitations

We investigate the response bandwidth of a superheterodyne Rydberg receiver at a room-temperature vapor cell, and present an architecture of multi-channel lasers excitation to increase the response bandwidth and keep sensitivity, simultaneously. Two microwave fields, denoted as a local oscillator (LO) $E_{LO}$ and a signal field $E_{Sig}$, couple two Rydberg states transition of $|52D_{5/2}\rangle\to |53P_{3/2}\rangle$. In the presence of the LO field, the frequency difference between two fields can be read out as an intermediate frequency (IF) signal using Rydberg electromagnetically induced transparency (EIT) spectroscopy. The bandwidth of the Rydberg receiver is obtained by measuring the output power of IF signal versus the frequency difference between two fields. The bandwidth dependence on the Rabi frequency of excitation lasers is presented, which shows the bandwidth decrease with the probe Rabi frequency, while it is quadratic dependence on the coupling Rabi frequency. Meanwhile, we investigate the effect of probe laser waist on the bandwidth, showing that the bandwidth is inversely proportional to the laser waist. We achieve a maximum response bandwidth of the receiver about 6.8~MHz. Finally, we design an architecture of multi-channel lasers excitation for increasing the response and keeping the sensitivity, simultaneously. Our work has the potential to extend the applications of Rydberg atoms in communications

P-Selectin and P-Selectin Glycoprotein Ligand 1 Are Major Determinants for Th1 Cell Recruitment to Nonlymphoid Effector Sites in the Intestinal Lamina Propria

The recruitment of activated T cell subsets to sites of effector immune responses is mediated by homing receptors induced upon activation in secondary lymphoid tissue. Using an adoptive transfer model, the intestinal recruitment of CD4+ T cells activated with intraperitoneal antigen in complete Freund's adjuvant was examined. The data demonstrate that activated CD4+ T cells recruited to intestinal Peyer's patches (PP) and lamina propria (LP) up-regulate functional P-selectin glycoprotein ligand 1 (PSGL-1). Blockade of IL-12 inhibited functional PSGL-1 expression and reduced PP and LP CD4+ T cell recruitment by >40%. P-Selectin blockade reduced LP recruitment of activated cells by 56% without affecting PP recruitment. Studies of mice examined 3 d after adoptive transfer of differentiated T cell subsets revealed that Th1 but not Th2 cells were recruited to small intestine PP and LP. Mucosal addressin cell adhesion molecule blockade reduced Th1 recruitment to PP by 90% and to LP by >72%, whereas P-selectin blockade reduced Th1 recruitment to PP by 18% and Th1 recruitment to LP by 84%. These data suggest that IL-12–induced functional PSGL-1 expression is a major determinant for the recruitment of Th1 effector cells to noninflamed as well as inflamed intestine

Hardware-algorithm collaborative computing with photonic spiking neuron chip based on integrated Fabry-P\'erot laser with saturable absorber

Photonic neuromorphic computing has emerged as a promising avenue toward building a low-latency and energy-efficient non-von-Neuman computing system. Photonic spiking neural network (PSNN) exploits brain-like spatiotemporal processing to realize high-performance neuromorphic computing. However, the nonlinear computation of PSNN remains a significant challenging. Here, we proposed and fabricated a photonic spiking neuron chip based on an integrated Fabry-P\'erot laser with a saturable absorber (FP-SA) for the first time. The nonlinear neuron-like dynamics including temporal integration, threshold and spike generation, refractory period, and cascadability were experimentally demonstrated, which offers an indispensable fundamental building block to construct the PSNN hardware. Furthermore, we proposed time-multiplexed spike encoding to realize functional PSNN far beyond the hardware integration scale limit. PSNNs with single/cascaded photonic spiking neurons were experimentally demonstrated to realize hardware-algorithm collaborative computing, showing capability in performing classification tasks with supervised learning algorithm, which paves the way for multi-layer PSNN for solving complex tasks.Comment: 10 pages, 8 figure

Melatonin Ameliorates Coxsackievirus B3-Induced Myocarditis by Regulating Apoptosis and Autophagy

Current therapeutics options for viral myocarditis are unsatisfactory. Melatonin (MLT), a hormone secreted by the pineal gland and other organs, has protective effects on ischemic heart injury. However, the potential therapeutic effect of MLT on viral myocarditis is unknown. In this study, we investigated the protective effect of MLT on viral myocarditis in a mouse model of myocarditis infected with coxsackievirus B3 (CVB3) and explored the probable mechanisms. Mice with CVB3-induced myocarditis displayed inflammatory cell infiltration and interstitial edema. MLT treatment significantly ameliorated the myocardial injuries. In addition, the rate of autophagy changed, although apoptosis was inhibited in mouse hearts following treatment with MLT. These results suggest that MLT has a strong therapeutic effect on acute viral myocarditis, which is associated with changes in autophagy and apoptosis in the heart. Thus, MLT could be a promising novel therapeutic approach against viral myocarditis

RESEARCH ON THE AXIAL CARRYING CAPACITY OF ANGULAR CONTACT BALL BEARINGS BASED ON COMBINED LOADS

Aim at difficulty to calculate the angular contact ball bearings’ axial carrying capacity in combined loads,considering the different of every roller suffered load and the actual contact angle,using deformation coordination principle and Hertz contact theory,the critical condition is that the actual contact angle is not exceed the safety contact angle,which any roller contact ellipse is not truncated. According to the above-mentioned and basing on a general algorithm of axial carrying capacity subjected to pure axial load,this paper proposed the improved algorithm to calculate the axial carrying capacity in combined loads. Relying on professional software analyzing,the improved algorithm has been well validated,and it is of engineering significance. Using the SKF 7316 BECBM bearing as an example,the above two algorithms are compared and analyzed. The results showed that: The radial load will make axial carrying capacity of angular contact ball bearing appropriately increase. The bending moment will make it significantly reduced,and with the increase of bending moment,the carrying capacity of axial load decreases faster. Compared with the radial load,bending moment is the dominant factor in changing of axial carrying capacity

Incidence and risks of subarachnoid hemorrhage in China

BACKGROUND AND PURPOSE—To determine incidence and risks of subarachnoid hemorrhage in China. METHODS—A prospective, population-based, 1:2 matched case–control study in Baotou, Inner Mongolia (≈2 million population) in 2009–2011. Multiple variable models used to determine relative risk and population-attributable risks for exposures. RESULTS—For a total of 226 patients (mean age, 59 years; 65% women; 434 controls), crude annual incidence (per 100 000) of subarachnoid hemorrhage was 6.2 (95% confidence intervals, 5.4–7.0); 4.3 (3.3–5.2) for men and 8.2 (6.9–9.6) for women. Compared with nonsmokers, adjusted relative risk of subarachnoid hemorrhage in current smokers was 2.31 (95% confidence interval, 1.31–4.09) but was 4.00 (1.62–9.89) in women. Population-attributable risk for smoking, hypertension, and low income were 18%, 36% and 59%, respectively. CONCLUSIONS—The incidence of subarachnoid hemorrhage in China is slightly lower than in Western countries and is related to smoking, hypertension, and poor socioeconomic status.Jingfen Zhang, Guorong Liu, Hisatomi Arima, Yuechun Li, Guojuan Cheng, Ivy Shiue, Lin Lv, Huiling Wang, Chunyang Zhang, Jianchun Zhao, Craig S. Anderson, and for the CHERISH Investigator

EXPERIMENTAL RESEARCH ON FOIL HYDRODYNAMIC AIR BEARING

Foil hydrodynamic air bearing is a kind of self-acting hydrodynamic gas bearing which the foil is used for elastic support. Because of its superior dynamic performance, it is widely used in high-speed turbine machinery, high-precision machine tools, aviation, aerospace, national defense and other high-end equipment fields. The foil hydrodynamic air bearing uses the air as the lubricating medium, according to the principle of dynamic pressure lubrication, a certain relative velocity should be reached between the journal and the bearing, so that the dynamic pressure film formed can overcome the radial force of the rotor and make the journal and bearing separate from the mechanical contact, that is, the rotational speed should reach the takeoff velocity of the foil hydrodynamic air bearing. In order to reduce the mechanical contact time between journal and bearing, determine the acceleration time of the motor and accurately measure its takeoff velocity, which has important engineering significance. A method to determine the takeoff speed of foil hydrodynamic air bearing by evaluating the vibration characteristics is proposed.The analysed result shows that accords with the actual result, which verifies the accuracy of the theoretical calculation method and is of great significance to the engineering application of air bearing

THE DYNAMICS RESEARCH AND TEST VERIFICATION BASED ON THE MISALIGNMENT OF THE HIGH-SPEED SHAFT

Based on the misalignment of the high shaft,the paper puts forward an improved algorithm about the exciting force and torque generated by the coupling misalignment,which is under the influence of gyroscopic effect and inertial forces.Through the centralized mass method,the rotor system is simplified as a multi-disc system. According to the force balance and the coordination deformation motion system the establishment of the rotor of the differential equations,obtained exciting force and torque. N rotor systems are calculated the exciting force and torque caused by coupling misalignment via using the improved algorithm. According to the principles of probability and statistics,its characterization value can be got. Taking a high-speed flywheel housing for example,as a load is applied in a limited element dynamic simulation model carried harmonic response simulation,vibration test results with comparative analysis of the test results,which have been well validated,with a certain sense of engineering applications

Interpretation of the essence of mesenchymal stem cells with the “kidney-triple energizers” system

Kidney and triple energizers are inseparable in structure and function. Therefore, it is proposed that “kidney-triple energizers” might be the essence of mesenchymal stem cells (MSCs) system. As a cardinal, this article aims to interpret the theoretical connotation of the mesenchymal stem cell system from the perspective of “the kidney essence is the body and the triple energizers is the function”. It is reflected in the kidney-three energizers system, and guided by the theory of traditional Chinese medicine, the modern technology of MSCs has achieved good results in the application of refractory diseases such as COVID-19, and a preliminary exploration of the integration of Chinese and Western medicine research has been carried out