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Tocochromanols, usually known as vitamin E, play a crucial role in human and animal nutrition. The enzyme homogentisate phytyltransferase (HPT) performs the first committed step of the vitamin E biosynthetic pathway. The full-length cDNA encoding HPT was isolated from Lactuca sativa L. by rapid amplification of cDNA ends (RACE). The cDNA, designated as LsHPT, was 1,670 bp long containing an open reading frame (ORF) of 1,185 bp which encoded a protein of 395 amino acids. Sequence analysis indicated that the deduced protein, named as LsHPT, shared high identity with other dicotyledonous HPTs. Real-time fluorescent quantitative PCR (qPCR) analysis revealed that LsHPT was preferentially expressed in mature leaves compared with other tissues. When lettuce plants were subjected to drought and high-light stress treatments, LsHPT expression was markedly increased. Expression of LsHPT in Arabidopsis showed that LsHPT could enhance the α-tocopherol biosynthesis in Arabidopsis. Transient expression of LsHPT via agroinfiltration resulted in 9-fold increase in LsHPT mRNA level and nearly 18-fold enhancement in α-tocopherol content compared with the negative controls. [ABSTRACT FROM AUTHOR]

Urban water supply headworks systems are usually designed to provide high security against drought. The best way to evaluate this security is to use Monte Carlo simulation which is computationally expensive. The advent of parallel computing technology in conjunction with genetic algorithms has made it practicable to optimize operation for drought security. Nonetheless, computation turnaround times remain long. This paper presents a simple heuristic called replicate compression to improve Monte Carlo efficiency. It exploits the well known concept of a critical period. In a high reliability system there should be few critical periods. Therefore, restricting simulation to such periods should bring about substantial savings in computational effort. It was found for problems where the objective function evaluation is only affected by what happens during critical periods, replicate compression provides an effective means for substantially reducing simulation effort. The case study involving a nine-reservoir urban headworks system showed the actual reduction in effort depended on the stress experienced by the system, which in turn affected the frequency of critical periods. Even when the objective function is affected by decisions outside the critical period, replicate compression may provide a useful result by helping to guide the specification of a reduced search space for the genetic algorithm. This strategy can bring about substantial savings in turnaround time. [ABSTRACT FROM AUTHOR]

Tα1 (thymosin α1), an immune booster, plays an important role in the maturation, differentiation and function of T-cells. It can also activate the production of cytokines in dendritic cells. Tα1 is one of two thymosin proteins that have potential future clinical applications. In order to express Tα1 protein in plants, we designed and synthesized the Tα1 gene according to the plant codon usage bias and created a novel 4×Tα1 concatemer (four copies of the Tα1 gene arranged end-to-end in tandem, designated 4×Tα1). Subsequently, a plant binary expression vector, PG-pRD12-4×Tα1, was constructed and introduced into tomato via Agrobacterium tumefaciens-mediated transformation. Through selection, 54 regenerated tomato plants resistant to kanamycin were obtained, and four transgenic tomato plants were further confirmed by PCR and Southern blotting. RT–PCR (reverse transcription–PCR) analysis showed that the 4×Tα1 gene was transcribed specifically in tomato [Solanum lycopersicum (formerly Lycopersicon esculentum)] fruits. ELISA analysis showed that the content of the 4×Tα1 protein reached a maximum of 6.098 μg/g fresh weight in mature tomato fruit. Western-blot analysis further confirmed the expression of 4×Tα1 protein in transgenic tomato fruits. The MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay showed the 4×Tα1 protein derived from transgenic tomatoes exhibited bioactivity that can stimulate the proliferation of mice splenic lymphocytes in vitro, and the specific activity of Tα1 protein from the artificial system was higher than that from the synthetic Escherichia coli system. This study is the first to report successful expression of bioactive Tα1 in plants, and also it will provide the basis for further development of the plant system to produce Tα1. [ABSTRACT FROM AUTHOR]

Angiotensin (Ang) II regulates adrenal steroidogenesis and adrenal cortical arterial tone. Vascular metabolism could decrease Ang II concentrations and produce metabolites with vascular activity. Our goals were to study adrenal artery Ang II metabolism and to characterize metabolite vascular activity. Bovine adrenal cortical arteries were incubated with Ang II (100 nmol/L) for 10 and 30 minutes. Metabolites were analyzed by mass spectrometry. Ang (1-7), Ang III, and Ang IV concentrations were 146+/-21, 173+/-42 and 58+/-11 pg/mg at 10 minutes and 845+/-163, 70+/-14, and 31+/-3 pg/mg at 30 minutes, respectively. Concentration-related relaxations of U46619-preconstricted cortical arteries to Ang II (maximum relaxation=29+/-3%; EC(50)=3.4 pmol/L) were eliminated by endothelium removal and inhibited by the NO synthase inhibitor, nitro-L-arginine (30 micromol/L; maximum relaxation=14+/-7%). Ang II relaxations were enhanced by the angiotensin type-1 receptor antagonist losartan (1 micromol/L; maximum relaxation=41+/-3%; EC(50)=11 pmol/L). Losartan-enhanced Ang II relaxations were inhibited by nitro-L-arginine (maximum relaxation=18+/-5%) and the angiotensin type-2 receptor antagonist PD123319 (10 micromol/L; maximum relaxation=27+/-5%). Ang (1-7) and Ang III caused concentration-related relaxations with less potency (EC(50)=43 and 24 nmol/L, respectively) but similar efficacy (maximum relaxations=39+/-3% and 48+/-5%, respectively) as losartan-enhanced Ang II relaxations. Ang (1-7) relaxations were inhibited by nitro-L-arginine (maximum relaxation=16+/-4%) and the Ang (1-7) receptor antagonist 7(D)-Ala-Ang (1-7) (1 micromol/L; maximum relaxation=10+/-3%) and eliminated by endothelium removal. Thus, Ang II metabolism by adrenal cortical arteries to metabolites with decreased vascular activity represents an inactivation pathway possibly decreasing Ang II presentation to adrenal steroidogenic cells and limits Ang II vascular effects. [ABSTRACT FROM AUTHOR]

Tα1 (thymosin α 1) is important in treating immunodeficiency and other diseases. In order to study the feasibility of expressing Tα1 in plants, as the first attempt, we designed and synthesized the Tα1 gene according to the plant codon usage preference and constructed the 4×Tα1 concatemer (four copies of a DNA sequence arranged end-to-end in tandem). The latter was inserted into Escherichia coli expression vector pQE30, resulting in a recombinant plasmid that was subsequently transformed into E. coli M15. The 4×Tα1 concatemer protein was successfully expressed in E. coli in a soluble form. The expressed protein was purified and its bioactivity was analysed by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide] assay. Preliminary results showed that the 4×Tα1 concatemer protein could stimulate the mice spleen lymphocyte proliferation. This is the first report on the expression of 4×Tα1 concatemer that was synthesized according to plant codon usage preference in an E. coli expression system. The present study provides the basis for expressing the synthesized active Tα1 gene in plants in the future. [ABSTRACT FROM AUTHOR]

Coal resource is abundant in China, while the reserves of natural gas and petroleum are limited. Due to the rapid increase in the number of automobiles, a competitive way to produce liquid fuels from coal is urgently needed in China. A so-called 'coal topping process" is under development at the Institute of Process Engineering, Chinese Academy of Sciences, from which liquid products can be obtained by flash pyrolysis in an integrated circulating fluidized bed system. In order to achieve a high field of liquid products from high volatile coal, controlling the residence time of coal particles and produced gas may be of importance for minimizing the degree of the secondary reactions; i.e., polymerization and cracking of the liquid products. Experiments of the flash pyrolysis of coal have been conducted in an entrained bed reactor which is especially designed to study the influence of the coal particle residence time on the product distribution. The results show that the gaseous, liquid, and solid product distribution, the gas' compositions as well as the liquid compositions depend strongly on the gas and particle residence time. [ABSTRACT FROM AUTHOR]

Adrenic acid (docosatetraenoic acid), an abundant fatty acid in the vasculature, is produced by a two-carbon chain elongation of arachidonic acid. Despite its abundance and similarity to arachidonic acid, little is known about its role in the regulation of vascular tone. Gas chromatography/mass spectrometric analysis of bovine coronary artery and endothelial cell lysates revealed arachidonic acid concentrations of 2.06 ± 0.01 and 6.18 ± 0.60 µg/mg protein and adrenic acid concentrations of 0.29 ± 0.01 and 1.56 ± 0.16 µg/mg protein, respectively. In bovine coronary arterial rings preconstricted with the thromboxane mimetic U-46619, adrenic acid (10-9-10-5 M) induced concentration-related relaxations (maximal relaxation 83 ± 4%) that were similar to arachidonic acid relaxations. Adrenic acid relaxations were blocked by endothelium removal and the K+ channel inhibitor, iberiotoxin (100 nM), and inhibited by the cyclooxygenase inhibitor, indomethacin (10 µM. maximal relaxation = 53 ± 4%), and the cytochrome P-450 inhibitor, miconazole (10 µM, maximal relaxation 52 ± 5%). Reverse-phase HPLC and liquid chromatography/mass spectrometry isolated and identified numerous adrenic acid metabolites from coronary arteries including dihomo (DH)-epoxy-eicosatrienoic acids (EETs) and DH-prostaglandins. DH-EET [16,17-, 13,14-, 10,11-, and 7,8- (10-9-10-5 M)] induced similar concentration-related relaxations (maximal relaxations averaged 83 ± 3%). Adrenic acid (10-6 M) and DH-16,17-EET (10-6 M) hyperpolarized coronary arterial smooth muscle. DH-16,17-EET (10-8-10-6 M) activated iberiotoxin-sensitive, whole cell K+ currents of isolated smooth muscle cells. Thus, in bovine coronary arteries, adrenic acid causes endothelium-dependent relaxations that are mediated by cyclooxygenase and cytochrome P-450 metabolites. The adrenic acid metabolite, DH-16,17-EET, activates smooth muscle K+ channels to cause hyperpolarization and relaxation. Our results suggest a role of adrenic acid metabolites, specifically, DH-EETs as endothelium- derived hyperpolarizing factors in the coronary circulation. [ABSTRACT FROM AUTHOR]

Summary: Most current medical images are collected in the presence of interference by ignored interferences such as illumination, occlusion, etc. The recognition rate is low for multi‐resolution images in the case of color distortion. Therefore, a novel fuzzy clustering recognition algorithm of multi‐resolution medical image was proposed in this paper. First, medical images were analyzed from both acquisition time, shooting angle, resolution, natural light measurement, and background. Secondly, in order to avoid partial occlusion, region was recalculated by correlation between Fourier and Merlin transform. Moreover, Euclidean distance between samples were identified by standardized eigenvalues, where smallest distance obtained maximum degree of membership. Experiment results showed that the proposed method had higher recognition rate (accuracy 90.46% and sensitiveness 97.89%) and stronger anti‐interference than current methods. [ABSTRACT FROM AUTHOR]

A transfer zone is a kind of structure that is produced to conserve deformation of a fault structure on both sides. Increasing numbers of transfer zones are being identified in rift basins, which are areas of petroleum accumulation and potential exploration targets. This paper provides a numerical simulation method for the genesis and development of transfer zones based on geomechanical modeling. On the basis of three-dimensional (3-D) seismic interpretation, using the Tongcheng fault as an example, the fault activity parameter and fault activity intensity index were established to quantitatively characterize the difference in fault activity on the two sides of a transfer zone. A geomechanical model was developed for a transfer zone in a rift basin, and the structural characteristics and genetic mechanism of a convergent fault were studied using paleostress and strain numerical simulations. Affected by different movements of boundary faults and basement faults, the evolution of the Tongcheng fault can be divided into three stages: (1) during the Funing period, which was the main development period of compound transfer faults, the activity, stress, and strain of the fault blocks on either side of the Tongcheng fault were obviously different; (2) during the Dainan period, which was the development stage of inherited compound transfer faults, the northern part of the Tongcheng area underwent local compression, and the T3 anticline began to form; and (3) during the Sanduo period, the Tongcheng fault experienced right-lateral strike-slip activity, where the activity showed two stages of change, first increasing and then decreasing, and the Tongcheng fault anticline developed. The superposition of multiple complex tectonic movements produced a transfer zone that has both strike-slip and extensional fault properties. The geomechanical model in this paper provides important insights for analyzing the evolution of transfer zones in rift basins. [ABSTRACT FROM AUTHOR]

AlSb/InAsSb heterostructures have been successfully grown on GaAs substrate by modulated molecular-beam epitaxy (MMBE). New shutter sequence has been presented and room temperature mobility of 16,170 cm²/V s has been achieved with our non-intentionally doped structures. With a view for optimization, we analyze variation of electron mobility induced by growth temperature and InAsSb thickness. By increasing growth temperature and thickness of InAsSb, improvement of electron mobility has been observed. With our optimized AlSb/InAsSb heterostructures, accurate control of composition in InAsSb alloy and reduced interface mixing have been confirmed by X-Ray diffraction and Raman spectroscopy measurements. [ABSTRACT FROM AUTHOR]