Privatization, Public R&D Policy, and Private R&D Investment in China's Agriculture

Private R&D is a major source of innovation and productivity growth in agriculture worldwide. This paper examines trends and determinants of agricultural R&D in China. Results show that while the public sector monopolized agricultural research until recently, private agricultural R&D has grown rapidly since 2000, driven largely by agribusiness privatization. Public-sector R&D investments in basic research also encouraged private R&D research, but public investments in technology development crowded out private R&D investment. China’s private R&D investment would grow more rapidly if the government shifted public resources from technology development to basic research.Agriculture, China, Private R&D, Privatization, Public R&D, Research and Development/Tech Change/Emerging Technologies,

Microstructure evolution under the space-time variational solidification conditions in a melt pool: A multi-scale simulation study

The properties of welded components are dominated by the microstructure evolution in the pool, where the solidification conditions are space-time variational. To represent the variational solidification conditions in the pool, the multi-scale simulation is carried out in this paper, combining microscopic Phase-Field (PF) equations with macroscopic thermal processes. First, two different models, the GR model and TF model, are employed to simulate the single crystal solidification at a local region of pool. Results suggest the TF model is more suitable to reflect the variational conditions than the GR model. Then the single-crystal solidification and poly-crystal solidification at the whole region of pool are carried out through the TF model. The results indicate the space-time variabilities of solidification conditions across the pool. Meanwhile, the variational solidification conditions influence the microstructure evolution significantly, including the onset of initial instability at the epitaxial growth stage and the directional evolutions of the converging grain boundaries (GBs) and diverging GBs at the competitive growth stage. Moreover, the formation of axial grain structures is observed, which can be regarded as the competition between the grains along the axial direction and radial direction. This study indicates the necessity of considering variational conditions in a pool. Meanwhile, the PF model can simulate microstructure evolution under variational conditions accurately, which has a great potential for investigating solidification dynamics in a melt pool.Comment: 30pages, 14 figure

Prevalence of mobile genetic elements and transposase genes in Vibrio alginolyticus from the southern coastal region of China and their role in horizontal gene transfer

Vibrio alginolyticus has high genetic diversity, but little is known about the means by which it has been acquired. In this study, the distributions of mobile genetic elements (MGEs), including integrating conjugative elements (ICEs), superintegron-like cassettes (SICs), insertion sequences (ISs), and two types of transposase genes (valT1 and valT2), in 192 strains of V. alginolyticus were investigated. ICE, SIC, and IS elements, valT1, and valT2 were detected in 8.9 %, 13.0 %, 4.7 %, 9.4 %, and 2.6 % of the strains, respectively. Blast searches and phylogenetic analysis of the acquired sequences of the ICE, SIC, IS elements and transposase genes showed that the corresponding homologues were bacterial and derived from extensive sources. The high prevalences of the se MGEs in V. alginolyticus implied the extensive and frequent exchange of genes with environmental bacteria and that these elements strongly contribute to the genetic and phenotypic diversity of the bacterium. To our knowledge, this is the fi rst report of V. alginolyticus harboring ICE and SIC elements. [Int Microbiol 2012; 15(4): 199-208

Increasing Response Diversity to Intraverbals in Children with Autism Spectrum Disorder

The purpose of this study was to evaluate the effects of intraverbal prompts on response diversity and novelty in intraverbals posed to children with autism spectrum disorder (ASD). The intraverbal prompts involving function, feature, and class (FFC) of an item were used in the training of three questions requiring multiple responses. Two Chinese boys with ASD (aged 5–6 years) served as participants. A multiple-probe across three behaviors design was employed. The results indicated that the intraverbal prompts effectively increased the number of divergent responses to all three questions. Novel responses emerged at a low level while generalization to similar questions was not observed following the training

Topological Atomic Spinwave Lattices by Dissipative Couplings

Recent experimental advance in creating dissipative couplings provides a new route for engineering exotic lattice systems and exploring topological dissipation. Using the spatial lattice of atomic spinwaves in a vacuum vapor cell, where purely dissipative couplings arise from diffusion of atoms, we experimentally realize a dissipative version of the Su-Schrieffer-Heeger (SSH) model. We construct the dissipation spectra of the topological or trivial lattices via electromagnetically-induced-transparency (EIT) spectroscopy. The topological dissipation spectrum is found to exhibit edge modes at dissipation rates within a dissipative gap, decoupled from the bulk. We also validate chiral symmetry of the dissipative SSH couplings. This work paves the way for realizing topology-enabled quantum correlations and non-Hermitian topological quantum optics via dissipative couplings.Comment: 5 pages, 4 figure

Co-extraction of high-quality RNA and DNA from rubber tree (Hevea brasiliensis)

High-quality nucleic acids are the basic requirement for performing genomic research. A reliable and efficient method was developed for co-extracting high-quality DNA and RNA from rubber tree (Hevea brasiliensis) in this study. Polyethylene glycol (PEG) and cetyltrimethylammonium bromide (CTAB) extraction buffer with high concentrations of polyvinylpyrrolidone (PVP) and β-mercaptoethanol was used in this study. The results show that 3.2% polyethylene glycol 8000 is the optimal concentration for successful separation of DNA and RNA. Spectrophotometric determination (A260/A280 and A260/A230 ratios), agarose electrophoresis analysis and reverse transcription (RT-PCR) of isolated nucleic acids indicate that high-quality DNA and RNA were extracted by this method. The general applicability of this method was also evaluated, and the results show that it was suitable for a variety of plants.Key words: Hevea brasiliensis, polyethylene glycol (PEG), nucleic acid, co-extraction, higher plants

Carboxymethyl chitosan-folic acid-conjugated Fe3O4@SiO2 as a safe and targeting antitumor nanovehicle in vitro

A synthetic method to prepare a core-shell-structured Fe(3)O(4)@SiO(2) as a safe nanovehicle for tumor cell targeting has been developed. Superparamagnetic iron oxide is encapsulated inside nonporous silica as the core to provide magnetic targeting. Carboxymethyl chitosan-folic acid (OCMCS-FA) synthesized through coupling folic acid (FA) with OCMCS is then covalently linked to the silica shell and renders new and improved functions because of the original biocompatible properties of OCMCS and the targeting efficacy of FA. Cellular uptake of the nanovehicle was assayed by confocal laser scanning microscope using rhodamine B (RB) as a fluorescent marker in HeLa cells. The results show that the surface modification of the core-shell silica nanovehicle with OCMCS-FA enhances the internalization of nanovehicle to HeLa cells which over-express the folate receptor. The cell viability assay demonstrated that Fe(3)O(4)@SiO(2)-OCMCS-FA nanovehicle has low toxicity and can be used as an eligible candidate for drug delivery system. These unique advantages make the prepared core-shell nanovehicle promising for cancer-specific targeting and therapy