Suchergebnisse

As a participator in corporate investment decision-making, the institutional investor is directly related to the corporate innovation investment. However, the economic policy uncertainty is aggravated by problems, such as economic slump and trade friction. Thus, institutional investors are not optimistic about the prospects of innovation investment. To explore the influence of institutional investors on corporate innovation investment from the perspective of economic policy uncertainty, using the 2010–2018 panel data in China and the fixed effect model, the influences of institutional investors on innovation investment and the moderating effects of the economic policy uncertainty were analyzed. Results show that institutional investors facilitate corporate innovation investment. Moreover, the increasing economic policy uncertainties repress the promoting effect of institutional investors on innovation investment. Furthermore, the institutional investors boost the corporate innovation investment by improving the internal control and relieving the financing constraints. For private companies, new and high-tech companies, the promoting effect of institutional investors on the corporate innovation investment is inhibited by the economic policy uncertainty to a small extent. For the listed companies located in areas with a high level of investor protection and intellectual property protection, the economic policy uncertainty has a minimal influence on the institutional investors and corporate innovation investment. The conclusions obtained from this study provide empirical evidence for giving full play to the role played by institutional investors in corporate innovative development. The conclusions also reveal, from the macroscopic level, that the consistency and stability of governmental economic policies have important effects on corporate development.

Jingjing Dong,1,* Geng Cui,2,* Long Bi,1,* Jie Li,3 Wei Lei11Institute of Orthopedics, Xijing Hospital, Fourth Military Medical University, Xi'an, Shaanxi, People's Republic of China; 2Institute of Orthopedics, General Hospital of PLA, Beijing, People's Republic of China; 3Institute of Gynecology and Obstetrics, General Hospital of PLA, Beijing, People's Republic of China*These authors contributed equally to this workAbstract: In order to improve the mechanical and biological properties of calcium phosphate cement (CPC, nanometer-biomaterial) for bone reconstruction in the rabbit femoral defect model, fibrin glue (FG, the natural product, purified from the blood) was introduced at three different ratios. The CPC powder and the FG solution were mixed, respectively, at the powder/liquid (P/L) ratios (g/mL) of 1:1, 3:1, and 5:1 (g/mL), and pure CPC was used as a control. After being implanted into the femoral defect in rabbit, the healing process was evaluated by micro-computed tomography scan, biomechanical testing, and histological examination. By micro-computed tomography analysis, the P/L ratio of 1:1 (g/mL) group indicated the largest quantity of new bone formation at 4 weeks, 8 weeks, and 12 weeks after implantation, respectively. Bone volume per trabecular volume of the 1:1 group was highest in the four groups, which was 1.45% ± 0.42%, 7.35% ± 1.45%, and 29.10% ± 1.67% at 4 weeks, 8 weeks, and 12 weeks after the operation, respectively. In the biomechanical tests, the compressive strength and the elastic modulus of the three CPC–FG groups were much higher than those of the pure CPC group at the determined time point (P < 0.05). The histological evaluation also showed the best osseointegration in the 1:1 group at 4 weeks, 8 weeks, and 12 weeks after the operation, respectively. In the 1:1 group, the bone grew into the pore of the cement in the laminar arrangement and connected with the cement tightly at the 12th week after the operation. This present study indicated that the CPC–FG composite at the P/L ratio of 1:1 (g/mL) stimulated bone regeneration better than any other designed group, which suggested that CPC–FG at the P/L ratio of 1:1 has significant potential as the bioactive material for the treatment of bone defects.Keywords: calcium phosphate cements, fibrin glue, bone reconstruction, micro-CT, biomechanical testing, histological examination

AbstractTo achieve carbon neutrality, integrating intermittent renewable energy sources, such as solar and wind energy, necessitates the use of large-scale energy storage. Among various emerging energy storage technologies, redox flow batteries are particularly promising due to their good safety, scalability, and long cycle life. In order to meet the ever-growing market demand, it is essential to enhance the power density of battery stacks to lower the capital cost. One of the key components that impact the battery performance is the flow field, which is to distribute electrolytes onto electrodes. The design principle of flow fields is to maximize the distribution uniformity of electrolytes at a minimum pumping work. This review provides an overview of the progress and perspectives in flow field design and optimization, with an emphasis on the scale-up process. The methods used to evaluate the performance of flow fields, including both experimental and numerical techniques, are summarized, and the benefits of combining diverse methods are highlighted. The review then investigates the pattern design and structure optimization of serpentine- and interdigitated-based flow fields before discussing challenges and strategies for scaling up these flow fields. Finally, the remaining challenges and the prospects for designing highly efficient flow fields for battery stacks are outlined.