We conducted a case–control study using 190 Han children with and without autism to investigate prenatal and perinatal risk factors for autism in China. Cases were recruited through public special education schools and controls from regular public schools in the same region (Tianjin), with frequency matching on sex and birth year. Unadjusted analyses identified seven prenatal and seven perinatal risk factors significantly associated with autism. In the adjusted analysis, nine risk factors showed significant association with autism: maternal second-hand smoke exposure, maternal chronic or acute medical conditions unrelated to pregnancy, maternal unhappy emotional state, gestational complications, edema, abnormal gestational age (<35 or >42 weeks), nuchal cord, gravidity >1, and advanced paternal age at delivery (>30 year-old).

The energy in pulse capacitors need to discharge rapidly to obtain high peak power. However, the discharge energy density of antiferroelectric (AFE) dielectrics for pulse capacitors is traditionally evaluated by hysteresis loop (defined as quasi-static method). To verify whether the quasi-static method is suitable for pulse applications, AFE ceramics Pb0.94La0.04[(Zr0.70Sn0.30)0.86Ti0.14]O3 were prepared, and their discharge energy density was calculated by hysteresis loop and pulse current (defined as dynamic method), respectively. A significant difference was found between these two kinds of results. Under 36 kV/cm, the discharge energy density calculated by 1 Hz hysteresis loop was 0.35 J/cm3 while that by pulse discharge current was only 0.18 J/cm3. It was found that the discharge energy density declined with increasing test frequency (0.1 Hz–100 Hz) and decreased further via dynamic hysteresis loop in microseconds scale. This declination can be explained by the viscous force during the motion of the domain wall. Thus, for pulse capacitors, it is more reasonable and practical to evaluate discharge energy density of AFE by pulse current than by quasi-static hysteresis loop.

The profiles of marine boundary layer (MBL) cloud and drizzle microphysical properties are important for studying the cloud-to-rain conversion and growth processes in MBL clouds. However, it is challenging to simultaneously retrieve both cloud and drizzle microphysical properties within an MBL cloud layer using ground-based observations. In this study, methods were developed to first decompose drizzle and cloud reflectivity in MBL clouds from Atmospheric Radiation Measurement cloud radar reflectivity measurements and then simultaneously retrieve cloud and drizzle microphysical properties during the Aerosol and Cloud Experiments in the Eastern North Atlantic (ACE-ENA) campaign. These retrieved microphysical properties, such as cloud and drizzle particle size (r c and r m,d ), their number concentration (N c and N d ) and liquid water content (LWC c and LWC d ), have been validated by aircraft in situ measurements during ACE-ENA (~158 hr of aircraft data). The mean surface retrieved (in situ measured) r c , N c , and LWC c are 10.9 μm (11.8 μm), 70 cm −3 (60 cm −3 ), and 0.21 g m −3 (0.22 g m −3 ), respectively. For drizzle microphysical properties, the retrieved (in situ measured) r d , N d , and LWC d are 44.9 μm (45.1 μm), 0.07 cm −3 (0.08 cm −3 ), and 0.052 g m −3 (0.066 g m −3 ), respectively. Treating the aircraft in situ measurements as truth, the estimated median retrieval errors are~15% for r c ,~35% for N c ,~30% for LWC c and r d , and~50% for N d and LWC d . The findings from this study will provide insightful information for improving our understanding of warm rain processes, as well as for improving model simulations. More studies are required over other climatic regions. Key Points: • New methods are developed to simultaneously retrieve MBL cloud and drizzle microphysical properties in drizzling clouds • The retrievals are validated with in situ measurements with errors of 15% for r c , 35% for N c , 30% for LWC c and r m,d , and 50% for N d and LWC d . (2020). Profiles of MBL cloud and drizzle microphysical properties retrieved from ground-based observations and validated by aircraft in situ measurements over the Azores.

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Pb0.94La0.04[(Zr0.70Sn0.30)0.90Ti0.10]O3 antiferroelectric (AFE) bulk ceramics with both excellent energy storage and release properties were fabricated via the solid-state reaction method. The ceramics exhibited a high releasable energy density of 1.39 J/cm3, high efficiency of 92%, and good temperature stability under 104 kV/cm. Fast discharge current was measured, and a large current density up to 820 A/cm2 was achieved. The nonlinear dielectric behavior resulted in the variation of the discharge period of AFE ceramics. The stored charge was released completely due to the low remanent polarization, and the actually released energy density was about 1.0 J/cm3 in 400 ns. A high peak power density of 6.4 × 109 W/kg without a load resistor and an average power density of 3.16 × 108 W/kg with a 204.7 Ω load resistor were achieved in the rapid discharge process. The excellent energy storage and release properties indicate that the obtained antiferroelectric bulk ceramics are very promising for submicrosecond pulsed capacitors.

This study presents newly developed algorithms for retrieving ice cloud microphysical properties (ice water content (IWC) and median mass diameter (D m )) for the stratiform rain and thick anvil regions of deep convective systems (DCSs) using Next Generation Radar (NEXRAD) reflectivity and empirical relationships from aircraft in situ measurements. A typical DCS case (20 May 2011) during the Midlatitude Continental Convective Clouds Experiment (MC3E) is selected as an example to demonstrate the 4-D retrievals. The vertical distributions of retrieved IWC are compared with previous studies and cloud-resolving model simulations. The statistics from six selected cases during MC3E show that the aircraft in situ derived IWC and D m are 0.47 ± 0.29 g m À3 and 2.02 ± 1.3 mm, while the mean values of retrievals have a positive bias of 0.19 g m À3 (40%) and negative bias of 0.41 mm (20%), respectively. To evaluate the new retrieval algorithms, IWC and D m are retrieved for other DCSs observed during the Bow Echo and Mesoscale Convective Vortex Experiment (BAMEX) using NEXRAD reflectivity and compared with aircraft in situ measurements. During BAMEX, a total of 63, 1 min collocated aircraft and radar samples are available for comparisons, and the averages of radar retrieved and aircraft in situ measured IWC values are 1.52 g m À3 and 1.25 g m À3 with a correlation of 0.55, and their averaged D m values are 2.08 and 1.77 mm. In general, the new retrieval algorithms are suitable for continental DCSs during BAMEX, especially within stratiform rain and thick anvil regions.

The temperature‐dependent energy storage and dielectric properties of Pb0.90La0.04Ba0.04[(Zr0.7Sn0.3)0.88Ti0.12]O3 were investigated in this work. With the phase transition from antiferroelectric to paraelectric induced by temperature rise, the releasable energy density decreases from 0.74 J/cm3 (20°C) to 0.29 J/cm3 (140°C), whereas the discharge efficiency increases from 75.0% to 93.4%. The pulsed discharge current indicates that the stored energy can be released in less than 1 μs. The temperature has little impact on the amplitude of the current but influences the discharge duration time greatly. In addition, with the comprehensive analysis of hysteresis loops, the DC‐bias character of dielectric constant and the discharge current, the transition from strong nonlinearity to linearity of the dielectric along with the phase switching was confirmed. It proves that the vanishment of high‐electric‐field nonlinear polarization contributions causes the declination of releasable energy with the temperature rise.

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