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Vortex electromagnetic (EM) waves, with different orbital angular momentum (OAM) modes, have the ability to distinguish the azimuth of radar targets, and then the two-dimensional reconstruction of the targets can be achieved. However, the vortex EM wave imaging methods in published research have no ability to obtain the elevation of the targets, and thus, the three-dimensional spatial structure and richer feature information of the radar target cannot be obtained. Therefore, a three-dimensional imaging method of vortex EM waves with integer- and fractional-order OAM modes is proposed in this paper, which can realize a three-dimensional reconstruction of a radar target based on a uniform circular array (UCA) with two-step imaging. First, the vortex EM wave with integer- and fractional-order OAM modes is generated, and the echo model with different OAM mode types is established. Thereafter, the echo with integer order is processed to obtain the range-azimuth image by fast Fourier transform (FFT). Then, in order to realize the three-dimensional reconstruction, the echo with fractional order is processed by utilizing the butterfly operation and analyzing the characteristics of the fractional Bessel function. Moreover, the resolution and reconstruction precision of the azimuth and elevation are analyzed. Finally, the effectiveness of the proposed method is verified by simulation experiments.

On the basis of DSP digital signal processing chip TMS320F2812 function as the main control chip of power supply, this paper proposes a dual switch forward topology with RCC converter as auxiliary power supply,the bootstrap drive chip IR2110 as power drive circuit, a dual closed loop control strategy with voltage outer loop and current inner loop, and PID control algorithm using integral separation together with dead zone control. The experimental result show that the power supply structure is easy to operate, and the corresponding control strategy and algorithm effectively improve the stability of the power supply output voltage and the rapidness of the response of the system.

In order to realize higher speed and large flow network communication on the new manned spacecraft independently developed in China, it is necessary to apply Ethernet technology. Considering the cost and application prospect, it is planned to use industrial Ethernet control chip. So it is necessary to verify whether it can meet the special requirements of the space environment. According to the space environment of the manned spacecraft design orbit, and the sensitive characteristics of the Ethernet controller chip itself, it is necessary to focus on verifying its single-particle effect. This paper introduces in detail the single-event effect of the Ethernet controller in China for the first time. The Bi-ion and Kr ions of the HIRFL cyclotron are used to carry out the single-event effect on the KSZ8851-16MLLJ Ethernet MAC controller produced by MICREL. The evaluation test, including the single-particle test design, hardware platform, software functions and test data, finally gave the test conclusion.

It has been proposed that initial empirical broad-spectrum antibiotic therapy will result in better clinical outcomes and that shorter courses will reduce the ‘collateral damage’ of promoting antibiotic resistance. There are few data from Intensive Care Units (ICUs) that support this latter conclusion. A prospective observational study was undertaken at the National University Hospital, Singapore, to examine the relationship between duration of carbapenem therapy and subsequent nosocomial multidrug-resistant (MDR) bloodstream infection (BSI). Over a 2-year period, 415 ICU patients receiving empirical carbapenem therapy were prospectively followed. MDR BSI occurred on 35 occasions in 31 patients, comprising 21 carbapenem-resistant Acinetobacter baumannii, 3 carbapenem-resistant Pseudomonas aeruginosa and 11 meticillin-resistant Staphylococcus aureus (MRSA). There was no difference in the duration of carbapenems for those who developed MDR BSI compared with those who did not [median duration 8 days (range 3–23 days) vs. 9 days (range 3–59 days); P = 0.78]. On multivariate analysis using the Cox proportional hazard model the hazard ratio was 0.935 (P = 0.070). In this cohort of critically ill patients, a shorter duration of carbapenem therapy was not shown to protect against subsequent development of MDR BSI. Strategies that depend primarily on reducing broad-spectrum antibiotic duration may be inadequate in preventing the emergence of MDR organisms.

By using the Jordan–Wigner transformation and the integral Gaussian transformation, this paper studies the thermodynamic property of the one-dimensional spin- 1 2 XZ chain in the external magnetic field, with uniform long-range interactions among the z components of the spins. Analytical formulas and numerical solutions of the Helmholtz free energy, internal energy, specific heat, magnetization and isothermal susceptibility per site are obtained. The phase diagram of the system is also given at finite temperature. Under degenerate condition, our results agree with numerical results of the other literatures.

By using the mean-field Jordan–Wigner transformation analysis, this paper studies the one-dimensional spin-1/2 XYZ antiferromagnetic chain in the transverse field with uniform long-range interactions among the z-components of the spins. The thermodynamic quantities, such as Helmholtz free energy, the internal energy, the specific heat, and the isothermal susceptibility, are obtained. Under degenerating condition, our results agree with numerical results of the other literatures

To study the distribution of 5-FU in rat plasma and liver tissue following systemic or local 5-FU infusion.5-FU was administered at the dose of 20 mg/kg systemically via bolus injection through the jugular vein or locally via infusion through the hepatic artery and portal vein of the rats. High-performance liquid chromatography was used to measure 5-FU concentration in the plasma and liver tissue, and the pharmacokinetic parameters, penetration rate and therapeutic dominance of 5-FU were calculated.Systemic administration of 5-FU resulted in the peak 5-FU concentration (Cmax) and area under curve (AUC) in the liver tissue of 13.79-/+4.56 microg/g and 342.20-/+108.20 microg.min(-1).g(-1)g-1, with the plasma Cmax and AUC of 36.85-/+5.96 microg/g and 842.00-/+158.00 microg.min(-1).ml(-1), respectively. Local 5-FU administration through the hepatic artery resulted in Cmax and AUC in the liver tissue of 29.58-/+4.30 microg/g and 794.60-/+115.40 microg.min(-1).g(-1) and Cmax and AUC in the plasma of 24.39-/+4.63 microg/g and 639.70-/+133.80 microg.min(-1).ml(-1), respectively. After administration through the portal vein, the Cmax and AUC of 5-FU was 28.21-/+4.46 microg/g and 733.60-/+180.3 microg.min(-1).g(-1) in the liver tissue, and 21.02-/+4.06 microg/ml and 529.80-/+111.50 microg.min(-1).ml(-1) in the plasma, respectively.Compared with systemic venous bolus injection, administration through the hepatic artery and portal vein can significantly increase 5-FU concentration in the liver, and decrease its concentration in the peripheral blood.