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Chinese endemic wheat landraces possess unique morphological features and desirable traits, useful for wheat breeding. It is important to clarify the relationship among these landraces. In this study, 21 accessions of the four Chinese endemic wheat landrace species were investigated using single-copy genes encoding plastid Acetyl-CoA carboxylase (Acc-1) and 3-phosphoglycerate kinase (Pgk-1) in order to estimate their phylogenetic relationship. Phylogenetic trees were constructed using maximum parsimony (MP), maximum likelihood (ML) and Bayesian, and TCS network and gene flow values. The A and B genome sequences from the Pgk-1 loci indicated that three accessions of Triticum petropavlovskyi were clustered into the same subclade, and the T. aestivum ssp. tibetanum and the Sichuan white wheat accessions were grouped into a separate subclade. Based on the Acc-1 gene, T. aestivum ssp. tibetanum and T. aestivum ssp. yunnanense were grouped into one subclade in the A genome; the B genome from T. petropavlovskyi and T. aestivum ssp. tibetanum, and the Sichuan white wheat complex and T. aestivum ssp. tibetanum were grouped in the same clades. The D genome of T. aestivum ssp. yunnanense clustered with T. petropavlovskyi. Our findings suggested that (1) T. petropavlovskyi is distantly related to the Sichuan white wheat complex; (2) T. petropavlovskyi, T. aestivum ssp. tibetanum and T. aestivum ssp. yunnanense are closely related; (3) T. aestivum ssp. tibetanum is closely related to T. aestivum ssp. yunnanense and the Sichuan white wheat complex; and (4) T. aestivum ssp. tibetanum may be an ancestor of Chinese endemic wheat landraces.

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Abstract

A novel energetic material, 4,5-dihydroxyl-2-(dinitromethylene)-imidazolidine (DDNI), was synthesized by the reaction of FOX-7 and glyoxal in water at 70 °C. Thermal behavior of DDNI was studied with DSC and TG-DTG methods, and presents only an intense exothermic decomposition process. The apparent activation energy and pre-exponential factor of the decomposition reaction were 286.0 kJ mol−1 and 1031.16 s−1, respectively. The critical temperature of thermal explosion of DDNI is 183.78 °C. Specific heat capacity of DDNI was studied with micro-DSC method and theoretical calculation method, and the molar heat capacity is 217.76 J mol−1 K−1 at 298.15 K. The adiabatic time-to-explosion was also calculated to be a certain value between 14.54 and 16.34 s. DDNI presents lower thermal stability, for its two ortho-hydroxyl groups, and its thermal decomposition process becomes quite intense.

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Journal of Thermal Analysis and Calorimetry
Authors: Z. Xiao, D. Liu, C. Wang, Z. Cao, X. Zhan, Z. Yin, Q. Chen, H. Liu, F. Xu, and L. Sun

Abstract  

The effect of mechanical alloying on Zn-Sb alloy system is investigated with X-ray diffraction (XRD), laser grain size analysis and differential scanning calorimetry (DSC) respectively. The results of laser particle size analysis shows that the particle size decreases with increasing of the grinding time between 0 and 24 h. XRD and DSC results indicate that longer the grinding time of Zn-Sb is, the more content of Zn4Sb3 become in the product in this process.

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Scientometrics
Authors: Jun-Ying Fu, Xu Zhang, Yun-Hua Zhao, He-Feng Tong, Dar-Zen Chen, and Mu-Hsuan Huang

Abstract

Acupuncture, the most important nonpharmacological therapy in traditional Chinese medicine, has attracted significant attention since its introduction to the Western world. This study employs bibliometric analysis to examine the profile of publication activity related to it. The data are retrieved from the database of Science Citation Index Expanded during 1980–2009, and 7,592 papers are identified for analysis. This study finds that almost 20 % of papers are published in CAM journals, and the average cited times per acupuncture paper is 8.69. While the most cited article has been cited 2,109 times, however, 38.15 % of total publications have never been cited. Europe has the largest amount of authored papers with high h-index values; the USA has the largest number of publications on and citations of acupuncture based on country distribution, and this has continued as a significant rising trend. The proportion of collaborative papers shows this upward trend on the worldwide scale while the percentage shares of national collaborations are the highest. The USA produces the most international collaborative documents, although South Korea occupies the highest percentage figure for international collaborative papers. International collaborative papers are the most frequently cited. The average number of authors per paper is 3.69 in the top eight countries/regions. Papers contributed by South Korea are authored by the most people. International collaboration papers are authored by more people, except in Taiwan. South Korea's Kyung Hee University is ranked first in terms of number of papers while Harvard University in the USA accounts for the largest proportion of citations. The University of Exeter, Harvard University and Karolinska Institute have the highest h-index values.

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Journal of Radioanalytical and Nuclear Chemistry
Authors: D. Xu, Q. L. Ning, X. Zhou, C. L. Chen, X. L. Tan, A. D. Wu, and X. Wang

Summary  

Effects of ionic strength and of fulvic acid on the sorption of Eu(III) on alumina were investigated by using a batch technique. The experiments were carried out at T=25±1 °C, pH 4-6 and in the presence of 1M NaCl. The results indicate that sorption isotherms of Eu(III) are linear at low pH values. The sorption-desorption of Eu(III) on alumina at pH 4.4 is reversible, but a sorption-desorption hysteresis is found at pH 5.0. Fulvic acid has an obvious positive effect on the sorption of Eu(III) on alumina at low pH values. The migration of Eu(III) in alumina was studied by using column experiments and 152+154Eu(III) radiotracer at pH 3.8. For column experiments, Eu(III) sorbed on alumina can be desorbed completely from the solid surface at low pH values. The findings are relevant to the evaluation of lanthanide and actinide ions in the environment.

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Abstract

China's economy and technology have experienced spectacular growth since the Opening-up Policy adopted in 1978. In order to explore the innovation process and development of China, this study examines the inventive activities and the collaboration pattern of university, industry and government (UIG) in China. This study analyzes the Chinese patent data retrieved from the United States Patent and Trademark Office. Three models of UIG relations which represent different triple helix configurations are introduced. According to the property of patent assignee, patent ownership can be divided into three types: individuals, enterprises, and universities and research institutes. Furthermore, enterprises can be classified into state-owned enterprise (SOE), private-owned enterprise (POE) and foreign enterprise (FE). The corresponding relationship of patent ownership with UIG is set up. Through analyzing the issued year, it is found that the inventive activities of China have experienced three developmental phases and have been promoted quickly in recent years. The achievement of innovation activities in China primarily falls on the enterprise, especially FEs and POEs. The innovation strengths of the three development phases have shifted from government to university and research institute and then industry. According to co-patent analysis, it is found that the collaboration between university and industry is the strongest and has been intensified in recent years, but other forms of collaboration among UIG have been weak. In addition, an innovation relation model of China was set up. The evolution process of innovation systems was explored, from etatistic model, followed by improved “laissez-faire” model, and then shifting toward triple helix model.

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Cereal Research Communications
Authors: S.F. Dai, D.Y. Xu, Z.J. Wen, Z.P. Song, H.X. Chen, H.Y Li, J.R. Li, L.Z. Kang, and Z.H. Yan

A novel 4.0-kb Fy was sequenced and bacterially expressed. This gene, the largest y-type HMW-GS currently reported, is 4,032-bp long and encodes a mature protein with 1,321 amino acid (AA) residues. The 4.0-kb Fy shows novel modifications in all domains. In the N-terminal, it contains only 67 AA residues, as three short peptides are absent. In the repetitive domain, the undecapeptide RYYPSVTSPQQ is completely lost and the dodecapeptide GSYYPGQTSPQQ is partially absent. A novel motif unit, PGQQ, is present in addition to the two standard motif units PGQGQQ and GYYPTSPQQ. Besides, an extra cysteine residue also occurs in the middle of this domain. The large molecular mass of the 4.0-kb Fy is mainly due to the presence of an extra-long repetitive domain with 1,279 AA residues. The novel 4.0-kb Fy gene is of interest in HMW-GS gene evolution as well as to wheat quality improvement with regard to its longest repetitive domain length and extra cysteines residues.

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Journal of Thermal Analysis and Calorimetry
Authors: F. Xu, L. Sun, P. Chen, Y. Qi, J. Zhang, J. Zhao, Y. Liu, L. Zhang, Zhong Cao, D. Yang, J. Zeng, and Y. Du

Abstract  

The heat capacities of LiNH2 and Li2MgN2H2 were measured by a modulated differential scanning calorimetry (MDSC) over the temperature range from 223 to 473 K for the first time. The value of heat capacity of LiNH2 is bigger than that of Li2MgN2H2 from 223 to 473 K. The thermodynamic parameters such as enthalpy (HH 298.15) and entropy (SS 298.15) versus 298.15 K were calculated based on the above heat capacities. The thermal stabilities of them were investigated by thermogravimetric analysis (TG) at a heating rate of 10 K min−1 with Ar gas flow rate of 30 mL min−1 from room temperature to 1,080 K. TG curves showed that the thermal decomposition of them occurred in two stages. The order of thermal stability of them is: Li2MgN2H2 > LiNH2. The results indicate that addition of Mg increases the thermal stability of Li–N–H system and decrease the value of heat capacities of Li–N–H system.

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Scientometrics
Authors: Jia Zheng, Zhi-yun Zhao, Xu Zhang, Dar-zen Chen, Mu-hsuan Huang, Xiao-ping Lei, Ze-yu Zhang, Yun-hua Zhao, and Run-sheng Liu

Abstract

Patents are the manifestation of the industry's research and development (R&D) endeavor; therefore, this paper studies the industry evolution of and key technologies in China from the perspective of patent analysis. Patents in six types of industries, including Chemical (excluding Drugs), Computers and Communications, Drugs and Medical, Electrical and Electronics (E&E), Mechanical, and Others are analyzed in this study. Findings from the analysis show a steady increase of US granted utility patents in China as well as percentage of these patents in the world over the period between 2003 and 2008. All the above industries in China have been growing rapidly during this period, which is very different from the global industry development. Despite the rapid development, the citation rates of these patents have been low, reflecting a need for improvement in the quality of patents and R&D performance for these six industries in China in order to exert more influence in the industry world. The analysis on patents also reveals China's industry distribution to be similar to the global industry distribution, with the exception of E&E industry which weights over one third of the total patents in technologies. The E&E industry is also the field with largest economic growth which rises more rapidly after 2006 with a sudden increase of patents in USPC 361. Detailed tracking of the key technology evolution reveals that 90% of the newly issued patents in USPC 361 after 2006 are owned by Foxconn Technology Co., Ltd, pointing to an unbalanced R&D environment in China's E&E industry sector. By providing the insight into the evolution of China's industrial and technological development through the perspective of patent analysis, this paper hopes to provide an objective statistic reference for future policy directions and academic researches.

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Abstract

A rapid and sensitive High-Performance Liquid Chromatography-tandem Mass Spectrometry (HPLC/MS/MS) method for determining apremilast in beagle dog plasma and urine samples was developed and validated using clopidogrel as the internal standard (IS). Apremilast was extracted from the plasma and urine samples by liquid–liquid extraction using methyl tert-butyl ether. Chromatographic separation was performed using a C8 column with gradient elution and a mobile phase containing methanol and 0.1% formic acid. Quantification was achieved in multiple reaction monitoring (MRM) mode with a transition of m/z 461.3→178.2 for apremilast and m/z 322.2→184.1 for clopidogrel (IS). This method was validated regarding its specificity, linearity, precision, accuracy, and stability. The lower limit of quantification (LLOQ) for this method was 5 ng/mL, and the calibration curve was linear over 5–1,000 ng/mL. The intra- and inter-run coefficients of variance (CV) of aprelimast in plasma samples were less than 12.92% and 10.64%, respectively, while in urine samples, the CV were less than 11.84% and 10.20%, respectively. The samples were stable under the tested conditions. This method was successfully applied to a pharmacokinetic study in beagle dogs following oral administration of 10 mg of apremilast.

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