S&T activities and firm performance - microeconomic evidence from manufacturing in Shanghai

This paper examines the impact of R&D expenditure and technology import on the level and the growth of productivity, as well as on the general economic performance in manufacturing firms with various ownership structures in Shanghai, China. The empirical analyses are based on the firm-level information of a sample of manufacturing firms for the period 1998–2003. We find clear-cut evidence indicating that firms with foreign participation have a productivity advantage over their domestic counterparts. The expenditures on technology import not only have a direct and positive effect on productivity, but also indirectly enhance the absorptive capacity of firms to facilitate in-house R&D activities. This is particularly true for firms with foreign participation, or for firms in sectors with relatively high technical standards. Furthermore, R&D expenditure and technology import may also have positive effects on profitability and export performance, depending on the ownership structure of the firm and the technical standard in the sector.Science and Technology policy; Science and Technology investment; R&D

Parameters optimization of ground source heat pump system combined energy consumption and economic analysis using Taguchi method

In order to obtain a high performance and low cost of ground source heat pump (GSHP) system, a methodology based on Taguchi method and analysis of variance (ANOVA) is used to optimize design parameters of GSHP systems. Eight parameters of GSHP system are selected as control factors to investigate effect on the system. Energy efficiency ratio (EER), coefficient of performance (COP), net annual value (NAV) and the average temperature rise (TEM) in soil of GSHP system are chosen as response factors to evaluate the system performance. A GSHP system model software is established by TRNSYS to calculate the EER, COP, NAV and TEM for 36 times repeatedly according to the L36 (22, 63) mixed level Taguchi orthogonal array. The result showed that the design outlet temperature of heat pump unit is the most important parameter for EER and COP, of which the contribution of significance are 41.88% and 88.12% respectively. While the number of U-Tubes per borehole has the major contribution (84.64%) for NAV and borehole spacing contribute most (45.42%) to TEM. The optimum EER, COP, NAV and TEM for the system with the optimized parameters combination are found to be 3.9355, 3.0339, CNY 106445 yuan and 2.362 ℃ respectively, which have been validated by confirmatory experiment. The utility concept has been used in this paper to find the optimum parameters combination with comprehensive consideration of all response factors (EER, COP, NAV and TEM) and the optimum combination we can get is A2 B1 C3 D1 E1 F3 G1 H3 with the response factors of 3.873, 3.023, 107212 yuan and 2.774 ℃ for EER, COP, NAV and TEM respectively

Three dimensional numerical simulation of double-U pile heat exchangers

The Ground Source Heat Pump system with pile heat exchangers has been used in engineering in recent years. In this paper, a three-dimensional numerical model of double-U pile heat exchangers is established which was verified through the comparison with ground thermal response test results. The influencing factors for the heat exchange performance of double-U pile heat exchangers are analyzed including pile depth, inlet temperature, initial ground temperature and ground thermal conductivity. An improved method is proposed on the basis of the cylindrical source model, combining with the numerical model. The improved method which is simpler than general analytical model can be used to obtain the ground thermal properties and thermal resistance of energy pile

Transcriptomic and Physiological Variations of Three Arabidopsis Ecotypes in Response to Salt Stress.

Salt stress is one of the major abiotic stresses in agriculture worldwide. Analysis of natural genetic variation in Arabidopsis is an effective approach to characterize candidate salt responsive genes. Differences in salt tolerance of three Arabidopsis ecotypes were compared in this study based on their responses to salt treatments at two developmental stages: seed germination and later growth. The Sha ecotype had higher germination rates, longer roots and less accumulation of superoxide radical and hydrogen peroxide than the Ler and Col ecotypes after short term salt treatment. With long term salt treatment, Sha exhibited higher survival rates and lower electrolyte leakage. Transcriptome analysis revealed that many genes involved in cell wall, photosynthesis, and redox were mainly down-regulated by salinity effects, while transposable element genes, microRNA and biotic stress related genes were significantly changed in comparisons of Sha vs. Ler and Sha vs. Col. Several pathways involved in tricarboxylic acid cycle, hormone metabolism and development, and the Gene Ontology terms involved in response to stress and defense response were enriched after salt treatment, and between Sha and other two ecotypes. Collectively, these results suggest that the Sha ecotype is preconditioned to withstand abiotic stress. Further studies about detailed gene function are needed. These comparative transcriptomic and analytical results also provide insight into the complexity of salt stress tolerance mechanisms

Energy management of double layers shape-stabilized phase change materials wallboard in office building

A novel wallboard with double layers shape-stabilized phase change materials (SSPCMs) for year round energy management was proposed. Its energy saving potential in five typical climate regions of China was studied. One office room integrated with double layers SSPCMs wallboard was used for simulation platform. The other normal office room with the same envelope and just without double layers SSPCMs wallboard was used as reference room. Studies were conducted to investigate the energy saving potential of double layers SSPCMs wallboard in five cities representing five typical climate regions of China, including severe cold region, cold region, hot summer and cold winter region, hot summer and warm winter region, mild region. The optimal melting temperature and corresponding thickness of SSPCMs wallboard in five representative cities were given when the energy saving potential reached maximal value. It concluded that the optimal melting temperature of internal SSPCM layer was effected by indoor air temperature and the optimal melting temperature of external SSPCM layer was effected by outdoor solar air temperature. The regularity of optimal values in the five representative cities were given for reference in this scope

Identification of conserved and novel microRNAs from Liriodendron chinense floral tissues.

BACKGROUND: Liriodendron chinense (L. chinense) is an endangered basal angiosperm plant in China because of its low reproductive efficiency. Recently, miRNAs have obtained great attention because they can play important roles. Through high throughput sequencing technique, large amount of miRNAs were identified from different plant species. But there were few studies about the miRNAs in the basal angiosperms especially in the sexual reproduction process. RESULTS: Deep sequencing technology was applied to discover miRNAs in L. chinense flowers at different stages. After bioinformatic analysis, 496 putative conserved miRNAs representing 97 families and 2 novel miRNAs were found. Among them, one is previously regarded as gymnosperm specific. Their expressions were further validated by Real-time PCR for 13 selected miRNAs. Putative targeting genes were predicted and categorized with gene ontology (GO) analysis. About ten percents of the targets are involved in the reproduction process. Further expressional analysis showed that many of these miRNAs were highly related to the reproductive growth. CONCLUSIONS: This is the first comprehensive identification of conserved and novel miRNAs in L. chinense. The data presented here might not only help to fill the gap of miRNA registered about basal angiosperm plants but also contribute to understanding the evolution of miRNAs. The differential expression of some of the miRNAs and the prediction of their target genes are also helpful in understanding the regulation of L. chinense sexual reproduction

Gene, protein and network of male sterility in rice

Rice is one of the most important model crop plants whose heterosis has been well exploited in commercial hybrid seed production via a variety of types of male sterile lines. Hybrid rice cultivation area is steadily expanding around the world, especially in Southern Asia. Characterization of genes and proteins related to male sterility aims to understand how and why the male sterility occurs, and which proteins are the key players for microspores abortion. Recently, a series of genes and proteins related to cytoplasmic male sterility, photoperiod sensitive male sterility, self-incompatibility and other types of microspores deterioration have been characterized through genetics or proteomics. Especially the latter, offers us a powerful and high throughput approach to discern the novel proteins involving in male-sterile pathways which may help us to breed artificial male-sterile system. This represents an alternative tool to meet the critical challenge of further development of hybrid rice. In this paper, we reviewed the recent developments in our understanding of male sterility in rice hybrid production across gene, protein and integrated network levels, and also, present a perspective on the engineering of male sterile lines for hybrid rice production