SummaryAdult hippocampal neurogenesis was impaired in several Alzheimer's disease models overexpressing mutant human amyloid precursor protein (hAPP). However, the effects of wild-type hAPP on adult neurogenesis and whether the impaired adult hippocampal neurogenesis was caused by amyloid β (Aβ) or APP remained unclear. Here, we found that neurogenesis was impaired in the dentate gyrus (DG) of adult mice overexpressing wild-type hAPP (hAPP-I5) compared with controls. However, the adult hippocampal neurogenesis was more severely impaired in hAPP-I5 than that in hAPP-J20 mice, which express similar levels of hAPP mRNA but much higher levels of Aβ. Furthermore, reducing Aβ levels did not affect the number of doublecortin-positive cells in the DG of hAPP-J20 mice. Our results suggested that hAPP was more likely an important factor inhibiting adult neurogenesis, and Aβ was not the major factor affecting neurogenesis in the adult hippocampus of hAPP mice.

No abstract

A multiband high-isolation multiple-input multiple-output (MIMO) antenna using balanced mode and coupled neutralization line (NL) is presented in this article. The balanced modes of dipole and loop antennas, which leads to good isolation intrinsically are used for the 8 × 8 MIMO in the LTE bands 42 (3400-3600 MHz)/Chinese 5G band (3300-3400 and 3400-3600 MHz). The unbalanced mode of loop antennas, which optimized by decoupling structure are designed for the 4 × 4 MIMO in the LTE band 40 (2300-2400 MHz). Therefore, the eight-antenna array is formed by four dipole elements and four loop elements. The simulated and measured results show that the proposed antenna can cover 2300 to 2400 and 3300 to 3600 MHz, with reflection coefficient better than −6 dB and isolation higher than 15 dB. Good radiation performance and low envelope correlation coefficient can also be obtained. Specific absorption rate of user's hand is also discussed in this article. K E Y W O R D S5G smartphone, high isolation, MIMO, neutralization line decoupling, S-SAR | INTRODUCTIONAs the current 4G system can no longer meet the requirements of explosive communication data growth, 1-3 both industry and academia are focusing on realizing fifth generation (5G) communications. It has been proved that multipleinput and multiple-output (MIMO) antenna system can achieve large capacity and higher transmission rate for 5G systems below 6 GHz. [4][5][6][7][8][9][10][11][12][13][14][15][16] In the future, at least eight antenna elements should be integrated into a mobile terminal, which can achieve larger channel capacity and better communication reliability. Because of the trend of bezel-less screen design for cellphones, it is a big challenge to guarantee high isolation when more MIMO antenna elements are implemented in such small design space. 3 As the standard for 5G communication is now being formulated, some MIMO antennas designed for 5G smartphone

No abstract