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Background: This study aimed to compare the analgesic effects of programmed intermittent epidural boluses (PIEB) and continuous epidural infusion (CEI) for postoperative analgesia after elective cesarean section (CS). Methods: Seventy-four women who underwent elective CS were randomized to receive either PIEB or CEI. The PIEB group received 4 ml-intermittent boluses of 0.11% ropivacaine every hour at a rate of 120 ml/h. The CEI group received a constant rate of 4 ml/h of 0.11% ropivacaine. The primary outcome was the pain score at rest at 36 h after CS. Secondary outcomes included the pain scores during mobilization, time-weighted pain scores, the incidence of motor blockade, and complications-related epidural analgesia during 36 h after CS. Results: The pain score at rest at 36 h after CS was significantly lower in the PIEB group compared with that in the CEI group (3.0 vs. 0.0; median difference: 2, 95% CI [1, 2], P < 0.001). The mean time-weighted pain scores at rest and during mobilizations were also significantly lower in the PIEB group than in the CEI group (pain at rest; mean difference [MD]: 37.5, 95% CI [24.6, 50.4], P < 0.001/pain during mobilization; MD: 56.6, 95% CI [39.8, 73.5], P < 0.001). The incidence of motor blockade was significantly reduced in the PIEB group compared with that in the CEI group (P < 0.001). Conclusions: PIEB provides superior analgesia with less motor blockade than CEI in postpartum women after CS, without any apparent adverse events. [ABSTRACT FROM AUTHOR]

There has been growing interest in the field of wireless power transfer (WPT), especially for a high-power (Watt-level) application. Rectifiers are essential components for WPT, as they convert incoming RF into DC power. However, conventional Schottky diodes used in WPT exhibit their highest efficiency at low power levels typically less than few Watts. To address this limitation, we introduce a power dividing rectenna system that can handle beyond several Watts of input RF power. The proposed rectenna consists of a single patch antenna integrated with a radial power divider, whose output ports are connected to rectifiers. In this way, incident RF power can be distributed into lower levels at which Schottky diode-based-rectifier can accommodate. Via simulation and measurement, we demonstrate that the input power (about 10 W) received through the proposed structure can be uniformly distributed to each output port of the divider to be rectified at lower power levels, which are then combined at DC to provide several Watts of DC power. The proposed rectenna can be utilized in WPT applications requiring beyond several Watts. Furthermore, by configuring the proposed structure into an array, even higher power handling can be achieved for applications that require hundreds of Watts.

The conventional radar technology is based on linear detection—i.e., the same transmit and receive frequencies are used. However, with linear radars, difficulties arise when detecting electronic objects with relatively small radar cross section (RCS). To overcome these limitations, a nonlinear radar that can detect nonlinear responses (i.e., harmonic and intermodulation) scattered by electronic devices due to nonlinear interaction can be utilized. Nonlinear radars require a different analysis from linear radars for analyzing RCS. In this paper, we present an experimental analysis of the nonlinear RCS of various electronic devices. Unlike linear radars, RCS in nonlinear radars is determined by the amount of nonlinear responses backscattered to the radar. Therefore, we derive a radar equation accustomed to harmonic radars that consists of nonlinear RCS. We then obtain and analyze the nonlinear RCS of various targets from the measured harmonic responses of the targets based on the nonlinear radar equation.

This study aimed to determine the influence of pre-pregnancy body mass index on pregnancy outcomes in gestational diabetes mellitus (GDM), comparing underweight patients with GDM with normal weight patients with GDM. Maternal baseline characteristics, ultrasonographic results, and pregnancy and neonatal outcomes were reviewed in 946 women with GDM with singleton pregnancies. Underweight patients with GDM showed a benign course in most aspects during pregnancy, except for developing a higher risk of giving birth to small for gestational age neonates. Underweight women with GDM required less insulin treatment, had a higher rate of vaginal delivery, and had a lower rate of cesarean delivery. In addition, their neonates were more likely to have fetal abdominal circumference and estimated fetal weight below the 10th percentile both at the time of GDM diagnosis and before delivery. Notably, their risk for preeclampsia and macrosomia were lower. Collectively, our data suggest that underweight women with GDM may require a different approach in terms of diagnosis and management throughout their pregnancy. [ABSTRACT FROM AUTHOR]