Living Arrangements of the Elderly in China: Evidence from CHARLS

Recent increases in Chinese elderly living alone or only with a spouse has raised concerns about elderly support, especially when public support is inadequate. However, using rich information from the China Health and Retirement Longitudinal Study, we find that the increasing trend in living alone is accompanied with a rise in living close to each other. This type of living arrangement solves the conflicts between privacy/independence and family support. This is confirmed in further investigation: children living close by visit their parents more frequently. We also find that children who live far away provide a larger amount of net transfers to their parents, a result consistent with responsibility sharing among siblings. Having more children is associated with living with a child or having a child nearby, while investing more in a child's schooling is associated with greater net transfers to parents.living arrangement, coresidence, proximity of children, CHARLS

Simulation of Wind Power Integration with Modular Multilevel Converter-Based High Voltage Direct Current

The growing demand for large-capacity long distance transmission of wind power has boosted the development of flexible direct current (DC) transmission technology. To facilitate wind power integration, this paper designs a modular multilevel converter (MMC) for steady-state operation, using the parameters of the demonstration DC transmission project of offshore wind power in Sheyang County, eastern China\u27s Jiangsu Province. Relying on the simulation platform of PSCAD/EMTDC, the authors analyzed the proposed control theory, and verified that, under different working conditions (e.g., changing wind speed), the MMC-based high voltage direct current (MMC-HVDC) transmission system can integrate the wind power safely and efficiently. In addition, the authors discussed how to enhance the fault ride-through (FRT), a prominent problem in wind power operation, of the flexible DC system containing wind power, from the perspective of alternating current (AC) fault and DC fault

Is the status of gold threatened by Bitcoin?

This paper evinces the ability of gold to avoid risks during periods with great fluctuations in the Bitcoin market. We apply bootstrap full- and subsample rolling-window Granger causality tests to explore the causal relationship between Bitcoin price (BCP) and gold price (GP). The empirical results show that an increase in BCP can cause GP to decrease, indicating that the prosperity of the Bitcoin market undermines the hedging ability of gold. However, a decrease in BCP causes GP to increase, and it also emphasizes that the ability of gold to avoid risks persists. Hence, the status of gold will not be completely threatened by Bitcoin, and they are complementary to each other instead of in competition. In turn, both positive and negative influences of GP on BCP suggest that fluctuations in BCP can be predicted through the gold market. In situations of severe global uncertainty and complicated investment environments, investors can benefit from complementary markets to optimize their asset allocation. Additionally, countries can grasp the trends in Bitcoin and gold prices to prevent large fluctuations in both markets and to reduce the uncertainty of the financial system

Study on heat integration of supercritical coal-fired power plant with post-combustion CO₂ capture process through process simulation

Coal-fired power plant (CFPP) is one of the main sources of anthropogenic CO₂ emissions. Capturing CO₂ from CFPP by post-combustion process plays an important role to mitigate CO₂ emissions. However, a significant thermal efficiency drop was observed when integrating CFPP with post-combustion carbon capture (PCC) process due to the steam extraction for capture solvent regeneration. Thus research efforts are required to decrease this energy penalty. In this study, a steady state model for 600 MWe supercritical CFPP was developed as a reference case with a low heating value (LHV) based efficiency of 41.6%. A steady state model for MEA-based PCC process was also developed and scaled up to match the capacity of the CFPP. CO₂ compression process was simulated to give an accurate prediction of its electricity consumption and cooling requirement. Different integration cases were set up according to different positions of steam extraction from the CFPP. The results show that the efficiency penalty is 12.29% and 14.9% when steam was extracted at 3.64 bar and at 9.1 bar respectively. Obvious improvements were achieved by utilizing waste heat from CO₂ capture and compression process, taking part of low pressure cylinders out of service, and adding an auxiliary turbine to decompress the extracted steam. The efficiency penalty of the best case decreases to 9.75%. This study indicates that comprehensive heat integrations can significantly improve the overall energy efficiency when the CFPP is integrated with PCC and compression process

Effect of nematic order on the low-energy spin fluctuations in detwinned BaFe1.935_{1.935}Ni0.065_{0.065}As2_2

The origin of nematic order remains one of the major debates in iron-based superconductors. In theories based on spin nematicity, one major prediction is that the spin-spin correlation length at (0,$\pi$) should decrease with decreasing temperature below the structural transition temperature $T_s$. Here we report inelastic neutron scattering studies on the low-energy spin fluctuations in BaFe$_{1.935}$Ni$_{0.065}$As$_2$ under uniaxial pressure. Both intensity and spin-spin correlation start to show anisotropic behavior at high temperature, while the reduction of the spin-spin correlation length at (0,$\pi$) happens just below $T_s$, suggesting strong effect of nematic order on low-energy spin fluctuations. Our results favor the idea that treats the spin degree of freedom as the driving force of the electronic nematic order.Comment: 5 pages, 4 figure

Transmission of new CRF07_BC Strains with 7 amino acid deletion in Gag p6

A 7 amino acid deletion in Gag p6 (P6delta7) emerged in Chinese prevalent HIV-1 strain CRF07_BC from different epidemic regions. It is important to determine whether this mutation could be transmitted and spread. In this study, HIV-1 Gag sequences from 5 different epidemic regions in China were collected to trace the transmission linkage and to analyze genetic evolution of P6delta7 strains. The sequence analysis demonstrated that P6delta7 is a CRF07_BC specific deletion, different P6delta7 strains could be originated from different parental CRF07_BC recombinants in different epidemic regions, and the transmission of P6delta7 strain has occurred in IDU populations. This is for the first time to identify the transmission linkage for P6delta7 strains and serves as a wake-up call for further monitoring in the future; In addition, P6delta7 deletion may represent an evolutionary feature which might exert influence on the fitness of CRF07_BC strain