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As a key nitrogen (N) source, soil amino acids play an important role in plant N nutrition. However, how amino acids differentially influence the N use strategies of native and invasive plants remains unclear. We performed a potted experiment using five pairs of native and invasive plant congeners, which were subject to 23 N treatments (i.e., 20 protein primary amino acids, nitrate, ammonium, and control), each with 10 replicates. We determined their growth, biomass allocation, N use efficiency, and the growth advantage of plant invaders over their natives. Native and invasive plants used the same 18 amino acid N sources (i.e., a similar amino acid economics spectrum). The growth of plant invaders was invariably better than the growth of native plants, and this superior growth of invaders was linked to their higher root biomass allocation and greater N use efficiency. Additionally, invasive plants had a greater growth advantage on amino acid N than on inorganic N, so was this advantage greater on neutral amino acids than on acidic amino acids. These findings suggest that the differences in amino acid use strategies between invasive and native congeners could help to explain plant invasiveness, as indicated by a growth advantage.

This study examined the effect of peanut quality on the storage stability of peanut butter. The quality of 17 varieties of peanuts was analyzed, and each was used to prepare peanut butter. For different storage temperatures and durations, stability of the peanut butter was measured according to three indicators: peroxide value, acid value, and centrifugal rate. The correlation between peanut components and peanut butter storage stability was also investigated. The results indicated significant differences in fatty acid composition between different varieties of peanut. Peanut butter prepared with high oleic peanuts (Kainong 17-15) had a significantly longer shelf life than that of other varieties. The significant correlation between the stability of peanut butter and peanut quality suggests that oleic acid and linoleic acid were the main influencing factors on stability. This study finds that the high oleic peanuts (HOP) is the most suitable variety for making peanut butter, which can allow farmers and processors to choose the specific variety for better product and shelf life.

Cereals and oilseeds are the foundation of human survival which have attracted much attention due to their nutritional and functional properties for maintaining the healthy life. There are abundant varieties of cereals and oilseeds, however, for a long time, their process suitabilities are still unknown, resulting in the lack of precision processing. This paper summarized the characteristics of cereals and oilseeds, including sensory, physicochemical and processing qualities, their characteristic fingerprinting and products qualities. Furthermore, the quality fast detection method was also analyzed. It also explored the role of mathematical model and the standard evaluation index to determine the process suitability and discussed the opportunity for advanced model capability. We also prospected on scientific problems for expanding the predictive capabilities for processing suitabilities of these abundant varieties, focusing on the better results and advancements towards the processing of cereals and oilseeds products and improvement of their quality.

Apelin-13 plays an important role in the migration and proliferation of vascular smooth muscle cells (VSMCs); however, the underlying mechanisms are still unclear. Egr-1 is a nuclear transcription factor, which is considered to be the critical initiating factor of the processes of VSMC proliferation and migration. Egr-1 is known to regulate the expression of osteopontin (OPN), which is a marker of the phenotypic modulation that is a necessary condition of VSMC proliferation and migration. We hypothesized that the role of Apelin-13 is mediated via upregulation of Egr-1. To test this hypothesis, we analyzed the effects of Apelin-13 treatment on Egr-1 mRNA and protein expression in A10 rat aortic VSMCs by RT-PCR and Western blotting, respectively. Results showed that, Apelin-13 upregulated the expression of Egr-1. Furthermore, treatment with the extracellular-regulated protein kinase (ERK) inhibitor, PD98059, inhibited the upregulation of Egr-1 by Apelin-13. In addition, this upregulation was inhibited by treatment of VSMCs with the Egr-1 specific deoxyribozyme ED5 (DNAenzyme/10-23 DRz). Furthermore, ED5 treatment was found to significantly inhibit Apelin-13-induced migration and proliferation of VSMCs using transwell and MTT assays, respectively. The evaluation of OPN mRNA and protein expression levels by RT-PCR and Western blot analyses revealed that ED5 treatment also inhibited Apelin-13-induced OPN upregulation. The results of this study indicated that Apelin-13 upregulates Egr-1 via ERK. Furthermore, Apelin-13 induced the proliferation and migration of VSMCs as well as the upregulation of OPN via the upregulation of Egr-1. These results will provide an important theoretical and experimental basis for the control of inappropriate remodeling of vessel walls, and will hopefully lead to the prevention and treatment of vascular remodeling diseases.

The gene of xylanase ( xyn A) was amplified by RT-PCR from the total RNA of a themophilic fungus Thermomyces lanuginosus SY2. The sequence analysis showed that gene coding region of mature peptide contained 0.585 kb, which coded 194 amino acids. The putative amino acid sequence and DNA sequence of xylanase from T. lanuginosus SY2 (GenBank no.: GU166389) were 98.97 and 99.49% identical to the other T. lanuginosus (GenBank no.: U35436). A recombinant plasmid pPIC9K- xyn A was constructed by inserting gene xyn A into Pichia pastoris secretory vector pPIC9K. Linearized pPIC9K- xyn A was transformed into P. pastoris GS115 with the method of electroporation. The recombinant strain was identified by G418 selection and confirmed by PCR analysis. It was induced by 1.0% methanol at 28°C to express the recombinant xylanase. The results showed that the recombinant xylanase was secreted into extracellular fermentation liquid. The highest enzyme activity of 113.5 IU mL −1 and protein content of 889.7 μg mL −1 were detected for 216 h of induction. The optimal pH value and temperature of the enzyme activity was 5.5 and 65°C, respectively. The xylanase activity retained above 80% from pH value 2.5 to 8.5 for 48 h. The enzyme activity was above 85% at incubation temperature of 55°C.

Strain of Pseudomonas Lip35 producing lipase was isolated in a refrigerator. Lipase production and characterization of this strain were investigated under different conditions. The Pseudomonas was cultivated in shaking flasks in a fermentation medium in various nutritional and physical environments. Lipase production has been influenced by the presence of yeast-extract, soybean powder, NaCl, and Tween-80. Maximum lipase productivity was obtained when the physical environment of the fermentation medium was optimal for 67 h. The production of lipase reached 58.9 U mL −1 . The lipase of Pseudomonas Lip35 can be considered to be inducible, but the inducer had little influence on the production of lipase. The lipase was characterized and showed high lipolytic activity from pH 7.5–8.0. The optimum temperature was observed at 20°C and the thermal inactivation of lipase was obvious at 60°C. The lipase activity was inhibited by K + , stimulated by Ca 2+ , and thermostability decreased in the presence of Ca 2+ , therefore the lipase was Ca 2+ -dependent cold-adapted enzyme.

The gene encoding fibrinolytic enzyme from Bacillus sp. zlw-2 was cloned and sequenced (accession no. EU734749), which was 1 146 bp, encoded 381 amino acids and had 99% homology with Nattokinase YF308 and NAT. The genes encoding pre-pro-fibrinolytic enzyme (including signal peptide, propeptide, and mature peptide) and fibrinolytic enzyme (including mature peptide) were cloned into pET28a vector respectively and then transformed into Escherichia coli BL21 (DE3). The recombinant of pre-pro-fibrinolytic enzyme showed enzyme activity of 183 U mL −1 , while no detectable enzyme activity could be found from the recombinant of the mature peptide.

A combination method of the usual-PCR and reverse-PCR for the cloning of a novel lipase gene directly from the total genomic DNA of strain lip35 (Pseudomonas sp.) is described, whereby a lipase gene (lip) was cloned directly from genomic DNA. The sequence data have been deposited in the GenBank and EMBL data bank with the accession number EU414288. The nucleotide sequence showed a major open reading frame encoding a 59-kDa protein of 566 amino acid residues, which contained a lipase consensus sequence GXSXG. The lipase lip had 74 and 70% homologies with the lipases of an uncultured bacterium and P. fluorescens PfO-1, respectively, but it did not show any overall homology with lipases from other origins. The functional lipase was obtained when the lip gene was expressed in Pichia pastoris GS115.

We examine observational constraints on the generalized Chaplygin gas (GCG) model for dark energy from the 9 Hubble parameter data points, the 115 SNLS Sne Ia data and the size of baryonic acoustic oscillation peak at redshift, $z=0.35$. At a 95.4% confidence level, a combination of three data sets gives $0.67\leq A_s\leq 0.83$ and $-0.21\leq \alpha\leq 0.42$, which is within the allowed parameters ranges of the GCG as a candidate of the unified dark matter and dark energy. It is found that the standard Chaplygin gas model ($\alpha=1$) is ruled out by these data at the 99.7% confidence level., Comment: 13 pages, 5 figures, to appear in PLB

Polymer-supported phosphine ligand 3b derived from ferrocene was prepared, and applied in palladium-catalyzed Suzuki–Miyaura reactions. A range of aryl bromides can couple with phenylboronic acid to obtain corresponding biaryls in excellent yields. The recycling of the polymer-bound catalyst was tested without adding palladium.

A series of 1-(ferrocenylethyl)-3-substituted-imidazolium salts [3-substitute=2,6-di(iso-propyl)phenyl (1a), 2,4,6-trimethylphenyl (1b), tertbutyl (1c), I-Ad (1d), cyclohexyl (1e)] have been synthesized from a racemic ferrocertylethyl acetate and the corresponding N-substituted imidazole in high yields (70-94%). A combination of Pd(OAc)(2) and 1a-d was found to form an excellent catalyst system for the Suzuki-Miyaura cross-coupling reactions of aryl bromides with phenylboronic acid in the presence of Cs2CO3 (c) 2006 Elsevier B.V. All rights reserved.

The thermodynamics of a static spherically symmetric black hole-global monopole system is investigated by two methods: surface gravity and the euclidean path integral. It is shown that if the mass of the black hole that swallows the monopole is sufficiently large compared to that of the monopole, then the Hawking temperature is decreased and the horizon area is raised by the presence of a global monopole, but the entropy-horizon area relation S = 14A, where S is the entropy and A is the horizon area, is unaltered. It is found that the coalescence of a sufficiently heavy black hole with a global monopole is thermodynamically permissible because it is in accord with the second law of thermodynamics, i.e., the Hawking area theorem; such a black hole with a global monopole, if it exists in the first place, will not decay to a black hole without a global monopole neither by collapse nor by annihilation of the monopole quantum number via Higgs radiation. Also it is noted that the first law of black hole thermodynamics proposed by Bardeen, Carter and Hawking should be modified.

Mesa-structured ultra small intrinsic Josephson junctions with area of 0.3 x 0.3 mu m(2) are successfully fabricated on near optimally doped Bi2Sr2CaCu2O8+delta superconductors using electron beam lithography. Temperature and magnetic-field dependencies of the intrinsic tunneling spectra are reported and briefly discussed. (c) 2007 Elsevier B.V. All rights reserved.

Two SU(8) GUT models with a stable proton are proposed which can accommodate fractionally charged color singlets with charge ± 1 3 e , ± 1 2 e and low mass monopoles. Both models predict observable baryon and lepton number nonconservation such as the n− n oscillation with lifetime ∼10 9 −10 10 s, the process of the proton lifetimes in GUTs is discussed. missing energy, etc. The problem of how to solve the contradiction of theory with experiment for the simplest SU(5) prediction of the proton lifetime in GUTs is discussed.