Determinants of the Size and Structure of Corporate Boards: 1935-2000

We argue that the size and composition of corporate boards are determined by tradeoffs involving the information that directors bring to boards versus the coordination costs and free rider problems associated with their additions to boards. Our hypotheses lead to predictions that firm size and growth opportunities are important determinants of these board characteristics. Using a sample of 82 U.S. firms that survived over the period of 1935 through 2000, we find strong support for the hypotheses. The hypotheses also find support in the relation between changes in board size and firms' merger and divestiture activity, and changes in the geographical diversification of firms. We find no robust relation between firm performance and either board size or composition after accounting for the determinants of these board characteristics.Board size, board composition, mergers and acquisitions, firm size, growth opportunities, diversification, geographical diversification, firm performance, endogeneity

China’s Financial System: Opportunities and Challenges

We provide a comprehensive review of China’s financial system, and explore directions of future development. First, the financial system has been dominated by a large banking sector. In recent years banks have made considerable progress in reducing the amount of non-performing loans and improving their efficiency. Second, the role of the stock market in allocating resources in the economy has been limited and ineffective. We discuss issues related to the further development of China’s stock market and other financial markets. Third, the most successful part of the financial system, in terms of supporting the growth of the overall economy, is a non-standard sector that consists of alternative financing channels, governance mechanisms, and institutions. The co-existence of this sector with banks and markets can continue to support the growth of the Hybrid Sector (non-state, non-listed firms). Finally, among the policies that will help to sustain stable economic growth in China are those that reduce the likelihood of damaging financial crises, including a banking sector crisis, a real estate or stock market crash, and a “twin crisis” in the currency market and banking sector.

Corporate Diversification in China: Causes and Consequences

We examine the diversification patterns of almost all publicly listed non-financial companies in China during the 2001 to 2005 period. More than 70 percent of the firms in our sample are diversified. We document that patterns of diversification strongly depend on firms' political connections. Former local bureaucrats are more likely than other CEOs to enter multiple industries. This effect is particularly pronounced in state-owned enterprises (SOEs) that operate in weak institutional environments. These companies are particularly prone to entering low-growth, low-profitability, and unrelated industries. Consequently, the performance effects of diversification differ sharply across SOEs and private firms. While the latter earn a premium from diversifying their operations, SOEs do not. Our results are consistent with the view that provincial and local governments push Chinese SOEs into unattractive sectors of the economy and that politically connected CEOs use their relationships to build corporate empires.Corporate Diversification, Institutions, China

Zonal Soil Type Determines Soil Microbial Responses to Maize Cropping and Fertilization.

Soil types heavily influence ecological dynamics. It remains controversial to what extent soil types shape microbial responses to land management changes, largely due to lack of in-depth comparison across various soil types. Here, we collected samples from three major zonal soil types spanning from cold temperate to subtropical climate zones. We examined bacterial and fungal community structures, as well as microbial functional genes. Different soil types had distinct microbial biomass levels and community compositions. Five years of maize cropping (growing corn or maize) changed the bacterial community composition of the Ultisol soil type and the fungal composition of the Mollisol soil type but had little effect on the microbial composition of the Inceptisol soil type. Meanwhile, 5 years of fertilization resulted in soil acidification. Microbial compositions of the Mollisol and Ultisol, but not the Inceptisol, were changed and correlated (P < 0.05) with soil pH. These results demonstrated the critical role of soil type in determining microbial responses to land management changes. We also found that soil nitrification potentials correlated with the total abundance of nitrifiers and that soil heterotrophic respiration correlated with the total abundance of carbon degradation genes, suggesting that changes in microbial community structure had altered ecosystem processes. IMPORTANCE Microbial communities are essential drivers of soil functional processes such as nitrification and heterotrophic respiration. Although there is initial evidence revealing the importance of soil type in shaping microbial communities, there has been no in-depth, comprehensive survey to robustly establish it as a major determinant of microbial community composition, functional gene structure, or ecosystem functioning. We examined bacterial and fungal community structures using Illumina sequencing, microbial functional genes using GeoChip, microbial biomass using phospholipid fatty acid analysis, as well as functional processes of soil nitrification potential and CO2 efflux. We demonstrated the critical role of soil type in determining microbial responses to land use changes at the continental level. Our findings underscore the inherent difficulty in generalizing ecosystem responses across landscapes and suggest that assessments of community feedback must take soil types into consideration. Author Video: An author video summary of this article is available

Antibody-Targeted Immunocarriers for Cancer Treatment

Nanocarrier’s engineering based on fine chemical design and novel structural tailoring can provide practical solution to solve the problems in traditional cancer immunotherapy. Nanoimmunotherapy is thus defined as the application and further development of novel nanocarriers for enhancing immunotherapy. It has become one of the most intriguing fields due to its unique power in treatment and even cure of cancer since reported in last year. Herein, this chapter illustrates the state-of-the-art development in antibody engineering and cancer immunotherapy and gives an explanation why functional nanocarries including micelles and liposomes can be efficient for nanoimmunotherapy. We further illustrate how to promote the nanoimmunotherapy by the chemical design and carrier’s engineering for the first time

ELM of ELM-WD: An extremely low mass hot donor star discovered in LAMOST survey

The Extremely Low Mass White Dwarfs (ELM WDs) and pre-ELM WDs are helium core white dwarfs with mass $<\sim 0.3M_{\odot}$. They are formed in close binaries and have lost over half of their initial masses via Common Envelope (CE) ejection or stable Roche Lobe Over Flow (RLOF). Both evolution simulations and observations show that a lower mass limit for ELM WDs exists at $\approx0.14M_{\odot}$. Here we report the discovery of an extremely low mass ELM WD, ID70904216 in LAMOST survey, that may be lower than the ELM WD mass limit. Based on LAMOST and P200 spectroscopic observations, ID70904216 shows orbital period $P_{orb} =$ 0.219658 days and radial velocity semi-amplitude $K1=317.33km/s$, which gives the mass function of 0.73$M_{\odot}$, indicating the companion is a compact star. The low resolution spectra shows a F type star with $T_{\rm eff} \sim 7361K$ without emission features. The temperature is consistent with that derived from SED fitting($7440K$) and multi-color light curve solution($7400K$). The optical light curves, in ZTF g, r and i bands and Catalina V band, show ellipsoidal variability with amplitudes $\approx30\%$, suggesting that the visible companion is heavily tidal distorted. Combining with the distance from Gaia survey, the WD code modeling estimates that the mass of the visible star is $M1=0.08^{+0.06}_{-0.03}M_{\odot}$, and the mass of the invisible star is $M2=0.94^{+0.45}_{-0.10}M_{\odot}$. The radius of the visible donor is $R=0.29\pm0.01R_{\odot}$. The inclination angle is constrained between 60$^{\circ}$ and 90$^{\circ}$. The observations indicate the system is a pre-ELM WD + WD/NS binary system with an extremely low mass hot donor below the $0.14M_{\odot}$ theoretical limit.Comment: 16 pages, 10 figure

Microbial responses to inorganic nutrient amendment overridden by warming: Consequences on soil carbon stability.

Eutrophication and climate warming, induced by anthropogenic activities, are simultaneously occurring worldwide and jointly affecting soil carbon stability. Therefore, it is of great interest to examine whether and how they interactively affect soil microbial community, a major soil carbon driver. Here, we showed that climate warming, simulated by southward transferring Mollisol soil in agricultural ecosystems from the cold temperate climate zone (N) to warm temperate climate (C) and subtropical climate zone (S), decreased soil organic matter (SOM) by 6%-12%. In contrast, amendment with nitrogen, phosphorus and potassium enhanced plant biomass by 97% and SOM by 6% at the N site, thus stimulating copiotrophic taxa but reducing oligotrophic taxa in relative abundance. However, microbial responses to nutrient amendment were overridden by soil transfer in that nutrient amendment had little effect at the C site but increased recalcitrant carbon-degrading fungal Agaricomycetes and Microbotryomycetes taxa derived from Basidiomycota by 4-17 folds and recalcitrant carbon-degrading genes by 23%-40% at the S site, implying a possible priming effect. Consequently, SOM at the S site was not increased by nutrient amendment despite increased plant biomass by 108%. Collectively, we demonstrate that soil transfer to warmer regions overrides microbial responses to nutrient amendment and weakens soil carbon sequestration