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An expedient synthesis of β-silyl α-amino acids is reported via the application of visible-light-mediated hydrosilylation. The reaction utilizes readily accessible and structurally diverse hydrosilanes to provide radicals for conjugate addition to dehydroalanine ester and analogues. Notably, the use of chiral methyleneoxazolidinone as the substrate and chiral inducer enabled the highly stereoselective synthesis. Furthermore, the reaction could also be performed in a continuous flow fashion and scaled up to the gram scale.

This paper presents an Unmanned Surface Vehicle (USV) for multi-mission applications. A small catamaran equipped with remotely operated system based on wireless local area network is developed and used as a universal platform. Outfitted with different appliances and instruments, the USV is tested for various applications including harbor surveillance, water quality sampling, hydrologic survey, maritime search and rescue. Experiments show that the USV is applicable.Keywords-unmanned surface vehicle; harbor surveillance; water quality sampling; hydrologic survey; maritime search and rescue.

Purpose: In order to compensate for the early intrauterine growth restriction, small-for-gestational age (SGA) infants have “catch-up growth” after birth. Increased caloric intake has been suggested for SGA infants conventionally. It is important to determine if the early growth rate of body mass index (BMI) is associated with risk of persistent obesity later in life. In this longitudinal cohort study, we assessed the BMI of a large cohort of children who were SGA at birth to determine their risk of persistent obesity at school age (6–7 years) due to excessive weight gain in the first 3 years of life.Methods: We collected the height and weight data of 23,871 SGA babies. A polynomial function was used to fit the BMI-for-age z-score (BAZ) values of 0–6 years old SGA children and interpolate their growth trajectory. In addition, we screened out 6,959 children from 23,871 children to further evaluate the dynamic changes of early childhood BMI. We divided the school-age children into groups as non-obese (BAZ < 2) and obese (BAZ > 2), and determined the association between changes in BMI and school-age obesity.Results: From the perspective of BMI distribution, the interpolated growth trajectory indicated that SGA children reaching overweight status or developing obesity by 3 years of age, continued to have obesity until school age (R2, 0.65; R2, 0.21). The retrospective analysis showed that children who were overweight and had obesity during school age had a high BMI from early age. By analyzing the changes in early BMI, we found that the fastest growth of SGA children occurred in the early infancy before 6 months and they continued to grow rapidly for a period of time. Interestingly, former SGA children who maintained a near overweight (1 < BAZ < 2) status before the age of 2 maintained an appropriate growth rate and usually did not develop obesity.Conclusions: A rapid increase in BMI during early infancy in former SGA newborns leads to a persistent risk of obesity. The energy intake of SGA infants should appropriately meet the infants' growth needs and early BMI changes should be closely monitored for an optimal integrated management.

Featured Application: Authors are encouraged to provide a concise description of the specific application or a potential application of the work. This section is not mandatory.Abstract: High power cylindrical Ni-MH battery cells have a heavy heat load because of their high discharge rate and large equivalent internal resistance. This heavy heat load, together with an imbalanced flow in parallel liquid cooling systems, can lead to variances in the temperature of each cell in the entire battery pack, thereby reducing the life cycle of the battery pack. In this paper, a parallel-series combined liquid cooling system for a 288V Ni-MH battery pack was designed, and several parameters that influence the flow balance of the system by heat transfer and fluid dynamics were calculated. Then, a thermal-fluid simulation was executed with different parameters using StarCCM+ software, and the simulation results were validated by a battery pack temperature experiment on a bench and in a vehicle. The results indicate that the cell's temperature and temperature differences can be kept within an ideal range. We also determined that within the battery power requirements and structural spacing limits, the total flow rate of the cooling liquid, the cross-sectional area ratio of the main pipe to the branch pipes, and the number of internal supporting walls in each branch pipe need to be large enough to minimize the cell's maximum temperature and temperature differences.reduces the life cycle of a battery pack. At temperatures exceeding 50 • C, charging efficiency and battery life deteriorate the most rapidly due to heat [10,11]. Therefore, it is necessary to pay more attention to the research of battery thermal management system (BTMS), which is very important for battery performance, life and safety. Pesaran et al. [12] noted that Ni-MH and Li-ion batteries' ideal operating temperatures range from 25 to 40 • C, and the temperature differences between the cells within a battery pack should be below 5 • C. Literature ReviewPlenty of works have been done in the field of battery thermal management system for commercially sold EVs and HEVs in the market, such as direct air cooling, liquid cooling, phase change material, heat pipes, hybrid cooling system and other emerging cooling technologies.The air-cooling system uses air as the heat exchange medium to let the air sweep across the battery surface to take away the heat generated by the battery. The air-cooling system is the most widely used cooling mode with simple structure, light weight, low cost and convenient maintenance. Chen YF et al. [13] showed that the thermal conductivity of Li-ion battery was low, and air cooling alone could not meet the requirements of thermal management. Harmel et al. [14] and Chen et al. [15] analyzed the thermal balance of li-ion batteries and found that when the wind speed reached a certain degree, increasing the wind speed had little effect on the heat dissipation effect of the batteries. Nelson et al. [16] have shown that the cooling effect of an air-co...