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In this paper, a new two-parameter moisture sorption isotherm (MSI) model was developed based on the non-random two-liquid (NRTL) theory. Compared to the most accepted theory of MSI, i.e., the layered adsorption theory, which includes only the effect of water clustering near food surfaces, the NRTL theory considers the effects of both water clustering and food swelling in the description of water adsorption on foods. This new model, referred to as the NRTL-solid-liquid-mixture (NRTL-SLM) model, revealed a rough linearity relationship between the reciprocal of the natural logarithm of water activity (1/lnaw) and the equilibrium moisture content (m1). A new index, characterising the magnitude of the slope of the plot of 1/lnaw v. s. m1, was constructed for the hygroscopicity assessment of food products. This new index, referred to as the NHI index, was scaled between 0% and 100%, with the bigger value indicating higher hygroscopicity and 100% representing the hygroscopicity of glycerol. In order to evaluate the applicability and reliability of the NRTL-SLM model and NHI index, seven food samples, i.e., grapes, apples, pears, bananas, avocados, potatoes and beef, were selected. Glycerol was chosen as the hygroscopic reference material. The MSI data at 25 °C of all the eight materials, i.e., seven food products and glycerol, were subjected to model evaluation and index calculations. Our results showed that: (a) the NRTL-SLM model could satisfactorily fit the MSI curves of all the eight materials; (b) compared to the existing most successful MSI model, i.e., the Guggenheim-Anderson-deBoer (GAB) model, the NRTL-SLM model provides a slightly lower accuracy but is much simpler and requires fewer parameters; (c) the NHI index could correctly rank the hygroscopicity of the eight materials relative to each other; and (d) the existing most widely used and standardised physical parameter for MSI analyses, i.e., the monolayer moisture content (M0), which is typically calculated from the GAB model, could not be used as a measure of hygroscopicity for foods.

Artemisia annua, commonly known as sweet wormwood or Qinghao, is a shrub native to China and has long been used for medicinal purposes. A. annua is now cultivated globally as the only natural source of a potent anti-malarial compound, artemisinin. Here, we report a high-quality draft assembly of the 1.74-gigabase genome of A. annua, which is highly heterozygous, rich in repetitive sequences, and contains 63 226 protein-coding genes, one of the largest numbers among the sequenced plant species. We found that, as one of a few sequenced genomes in the Asteraceae, the A. annua genome contains a large number of genes specific to this large angiosperm clade. Notably, the expansion and functional diversification of genes encoding enzymes involved in terpene biosynthesis are consistent with the evolution of the artemisinin biosynthetic pathway. We further revealed by transcriptome profiling that A. annua has evolved the sophisticated transcriptional regulatory networks underlying artemisinin biosynthesis. Based on comprehensive genomic and transcriptomic analyses we generated transgenic A. annua lines producing high levels of artemisinin, which are now ready for large-scale production and thereby will help meet the challenge of increasing global demand of artemisinin.

Lithium sulfur batteries (LSBs) is one of the most promising battery systems for both green energy plants and electric vehicles power sources. High performance sulfur reservoirs have been considered as the most important component for LSBs to protect the soluble lithium polysulfides (LPSs) from shuttling to lithium anode. Herein, a desired titanium oxide nanowires clots (TOCs) with a two phase composition and high effective absorption surface area (270.1 m2g-1) is developed as the promising LPSs’ reservoirs for the accommodation of sulfur and LPSs. Benefitted from the synergistic effect generated from the unique structure of TOCs, the obtained S/TOCs cathode materials exhibit high specific capacity, high coulombic efficiency and excellent cyclic stability at 1C and 2C rate. The corresponding capacity fading rate of each cycle is only ~0.14% and 0.11 % for the LSBs being (dis)charged 1C and 2C, respectively.

Salmonella enterica is the most common foodborne pathogen worldwide, with 2,500 recognized serovars. Detection of S. enterica and its classification into serovars are essential for food safety surveillance and clinical diagnosis. The PCR method is useful for these applications because of its rapidity and high accuracy. We obtained 412 candidate detection targets for S. enterica using a comparative genomics mining approach. Gene ontology (GO) functional enrichment analysis of these candidate targets revealed that the GO term with the largest number of unigenes with known function (38 of 177, 21.5%) was significantly involved in pathogenesis (P10(-24)). All the candidate targets were then evaluated by PCR assays. Fifteen targets showed high specificity for the detection of S. enterica by verification with 151 S. enterica strains and 34 non-Salmonella strains. The phylogenetic trees of verified targets were highly comparable with those of housekeeping genes, especially for differentiating S. enterica strains into serovars. The serovar prediction ability was validated by sequencing one target (S9) for 39 S. enterica strains belonging to six serovars. Identical mutation sites existed in the same serovar, and different mutation sites were found in diverse serovars. Our findings revealed that 15 verified targets can be potentially used for molecular detection, and some of them can be used for serotyping of S. enterica strains.

The yft1 tomato mutant has a yellow-fruited phenotype controlled by a recessive gene of YFT1 allele, which has been shown by map-based cloning to be a homolog of ETHYLENE INSENSITIVE 2 (EIN2). Genetic lesion of YFT1 allele in yft1 is attributed to a 573 bp DNA fragment (IF573) insertion at 1,200 bp downstream of the transcription start site. Transcriptomic analysis revealed that YFT1 lesion resulted in 5,053 differentially expressed genes (DEGs) in yft1 pericarp compared with the M82 wild type cultivar. These were annotated as being involved in ethylene synthesis, chromoplast development, and carotenoid synthesis. The YFT1 lesion caused a reduction in its own transcript levels in yft1 and impaired ethylene emission and signal transduction, delayed chromoplast development and decreased carotenoid accumulation. The molecular mechanism underlying the downregulated YFT1 allele in yft1 was examined at both RNA and DNA levels. The IF573 event appeared to introduce two negative regulatory sequences located at -272 to -173 bp and -172 to -73 bp in the YFT1 allele promoter, causing alterative splicing due to introduction of aberrant splicing sites, and breaking upstream open reading frames (uORF) structure in the 5'-UTR. Those results a new provided insight into molecular regulation of color formation in tomato fruit.

Large amounts of industrial waste discharge have serious implications for the environment. The production of coarse Al-Si alloy by carbothermal reduction is considered to be one potential method for making use of industrial aluminiferous waste slag. Here, we discuss the influence of different processing parameters on electrolytic refining of aluminum alloy and investigate the mechanism of extracting Al from coarse Al-Si alloy in a low-temperature molten salt system. Aluminum is obtained with the use of coarse Al-Si alloy as a soluble anode in the AlCl3-NaCl-KCl molten salt system. The current efficiency reached over 94% when the electrolysis temperature was 170 ℃, the current density was 30 mA/cm2 and electrolysis was performed for 1.5 h. In the electrolysis process, Al in the coarse Al-Si alloy was present in the form of Al2Cl7− and AlCl4−, which precipitated at the cathode. The purity of aluminum electrodeposited on the aluminum cathode was 99.3%.

Summary Background and objective Cyclase-associated protein 2 (CAP2) has recently been suggested to be a candidate biomarker for hepatocellular carcinoma (HCC). We aim to investigate the application of CAP2 as a novel biomarker for HCC patients especially for those at early stage and are AFP-negative. Methods The CAP2 and AFP plasma levels were analyzed by enzyme-linked-immunosorbent assay in 86 HCC, 59 cirrhotic patients, and 30 normal individuals. Their correlation with HCC tumor behavior, disease stages, diagnostic sensitivity, specificity and accuracy were analyzed. Results The results showed that both CAP2 and AFP plasma levels in HCC patients were significantly elevated when compared to cirrhosis and controls. CAP2 levels correlate well with HCC patient's histological grade, clinical stage and tumor size, but not with patient's age, gender, hepatitis B virus infection status and plasma AFP level. CAP2 had better sensitivity as compared to AFP (82.6% vs 59.3%) for general HCC, and early stage of HCC patients (78.6% vs 40.4%). In addition, CAP2 is able to complement AFP to predict 82.9% of HCC in AFP-negative patients. Conclusion We suggest that CAP2 is a novel biomarker for HCC patient, this may be especially useful for detection of early stage HCC and when plasma AFP level is negative.

Using a comparative genomic method, 38 and 8 fragments were verified as specific identification targets for Salmonella Typhimurium and Enteritidis, respectively. Primer sets were designed based on these sequences and evaluated by PCR assays. Two primer sets targeting the STM4495 and SEN1392 genes with high specificity were selected for S. Typhimurium and Enteritidis, respectively, and a multiplex PCR method was developed for the identification of these bacteria based on these two primer sets and another primer set targeting the srfC gene specific for Salmonella enterica. The multiplex PCR also included an internal amplification control (IAC), which was constructed by psy gene from Chlorella protothecoides for process control to monitor potential PCR inhibitors. The sensitivity of this multiplex PCR was 89 fg and 138 fg of DNA per PCR for S. Typhimurium and S. Enteritidis, respectively. The detection limits were as low as 22–23 CFU per PCR for pure cultures of both serovars. Moreover, positive results were observed from milk samples that were initially contaminated with 2–3 CFU Salmonella after 12 h of enrichment at 37 °C. These results demonstrate that the comparative genomic method is a valuable tool for identifying new specific targets, a necessary step for developing rapid and accurate detection methods for foodborne pathogens.

The effect of Doppler broadening on dispersive and absorptive properties is theoretically investigated in the hot four-level electromagnetically induced transparency (EIT) atomic systems with two different types of two-photon interference. It is found that the dispersive behavior for the probe in the ladder-type atomic system with two-photon constructive interference will be changed from anomalous in cold atoms to normal in hot atoms, and the three-peak absorptive profile is shifted to a broadened spectrum with a shallow dip at the line center; as a comparison, there is always normal dispersion at the line center for the invert-Y-type atomic system with two-photon destructive interference, but the EIT window in the absorptive profile will be narrowed to subnatural linewidth (0.01Γ) at room temperature. The physics of those two different behaviors are discussed and compared in the dressed-state theory.

Anxiety disorders are among the most common and well studied psychiatric disorders in humans. A number of animal models have been established to study the mechanisms of anxiety and to test putative anxiolytic drugs. Gpr26 belongs to the G-protein-coupled receptor family and is exclusively expressed in brain tissue. To investigate the biological function of Gpr26 in vivo, we have generated Gpr26 knockout mice. The mutant mice grew and developed normally but displayed increased levels of anxiety-like behaviors in the open field and elevated plus maze tests, as well as a higher level of depression-like behaviors in the forced-swim and tail-suspension tests. Meanwhile, no significant alteration in spatial learning and memory abilities were found for Gpr26-deficient mice in the Morris water maze test. Previous studies demonstrated that lower protein kinase A (PKA)-cAMP responsive element-binding protein (CREB)-neuropeptide Y (NPY) signaling in the amygdala is linked to higher anxiety and excessive alcohol-drinking behaviors in rats. Therefore, we further examined the phosphorylated CREB (pCREB) and CREB levels in the brains of Gpr26-deficient mice. Reduced pCREB levels were observed in the central amygdala but not in the other regions, while total CREB levels remained comparable between wild-type and mutant mice. Combined, our data indicate that Gpr26 is important for emotion regulation in mice, a function probably mediated by the phosphorylation of CREB in the central amygdala.

Response surface methodology along with Box-Behnken design was firstly applied to optimize the extraction conditions for the polysaccharides from the roots of Isatis tinctoria L. The experimental data obtained were fitted to a second-order polynomial equation using multiple regression analysis. The 3-D response surface and the contour plots derived from the mathematical models were applied to determine the optimal conditions. The optimal conditions were extraction temperature (X1) 99.5 °C, extraction time (X2) 3.75 h and ratio of water to raw material (X3) 11.84 (v/w). Under these conditions, the maximal observed value extraction yield of Isatis root polysaccharides (IRPSs) was (11.19 ± 0.04)%, which was agreed with predicted value 11.17%. Pharmacological experiments indicated that IRPS have an appreciable ABTS radical scavenging ability in vitro and could increase IL-4 and IFN-γ mRNA expression in chicken lymphocytes obtaining maximum promoted effects of 70% and 115%, respectively. This study may facilitate a deeper understanding of IRPS to provide theoretical references.

A 5'-nuclease real-time PCR assay using a minor groove binding probe was developed for the detection of Salmonella enterica from artificially contaminated foods. S. enterica-specific sequences were identified by a comparative genomic approach. Several species-specific target sequences were evaluated for specificity. A real-time PCR assay was developed targeting a nucleotide sequence within the putative type III secretion ATP synthase gene (ssaN). An internal amplification control (IAC) probe was designed by randomly shuffling the target probe sequence and a single-stranded oligonucleotide was synthesized to serve as an IAC. The assay demonstrated 100% inclusivity for the 40 Salmonella strains tested and 100% exclusivity for 24 non-Salmonella strains. The detection limit of the real-time PCR assay was 41.2 fg/PCR with Salmonella Typhimurium genomic DNA and 18.6 fg/PCR using Salmonella Enteritidis genomic DNA; 8 and 4 genome equivalents, respectively. In the presence of a natural background flora derived from chicken meat enrichment cultures, the sample preparation and PCR method were capable of detecting as few as 130 Salmonella cfu/mL. Using the developed real-time PCR method to detect Salmonella in artificially contaminated chicken, liquid egg and peanut butter samples, as few as 1 cfu/10 g of sample was detectable after a brief (6h) non-selective culture enrichment.

ERF transcription factors can bind GCC boxes or non-GCC cis elements to regulate biotic and abiotic stress responses. Here, we report that an ERF transcription factor gene (GbERF2) was cloned by suppression subtraction hybridization from sea-island cotton after Verticillium dahliae attack. The GbERF2 cDNA has a total length of 1143 bp with an open reading frame of 597 bp. The genomic sequence of GbERF2 contains an intron of 515 bp. The gene encodes a predicated polypeptide of 198 amino acids with a molecular weight of 22.5 kDa and a calculated pI of 9.82. The GbERF2 protein has a highly conserved ERF domain while the nucleotide and amino acid sequences have low homology with other ERF plant proteins. An RNA blot revealed that GbERF2 is constitutively expressed in different tissues, but is higher in the leaves. High levels of GbERF2 transcripts rapidly accumulated when the plants were exposed to exogenous ethylene treatment and V. dahliae infection, while there was only a slight accumulation in response to salt, cold, drought and water stresses. In contrast, GbERF2 transcripts declined in response to exogenous abscisic acid (ABA) treatment. GbERF2 transgenic tobacco plants constitutively accumulated higher levels of pathogenesis-related gene transcripts, such as PR-1b, PR2 and PR4. The resistance of transgenic tobacco to fungal infection by Alternaria longipes was enhanced. However, the resistance to bacterial infection by Pseudomonas syringae pv. tabaci was not improved. These results show that GbERF2 plays an important role in response to ethylene stress and fungal attack in cotton.

Potassium channels are important for many physiological functions in plants, one of which is to regulate plant adaption to stress conditions. In this study, KCT2, the gene encoding a membrane-bound protein potassium channel (GenBank accession number: ), was isolated from Chinese cabbage (Brassica rapa ssp. Pekinensis) by RACE-PCR technique. Bioinformatics methods were performed for the gene structure and molecular similarity analysis. The KCT2 expression patterns under various stress conditions were studied by semi-quantitative RT-PCR. DNA gel blot was used to analyze genomic organization. The putative KCT2 was found to contain five membrane-spanning segments, a pore-forming domain (P-domain) between the last two transmembrane spans, a TxxTxGYGD motif in the P-domain and a putative cyclic nucleotide-binding-like domain within a long C-terminal region. KCT2 is closest to KAT2 in Arabidopsis. KCT2 could be a one-copy gene with different isoforms or belong to a small gene family with four or five members. KCT2 was expressed more strongly in leaves than in shoots and roots. KCT2 transcription products were up-regulated by a 4-h-incubation in abscisic acid (ABA) and various stress treatment including cold stress (4 degrees C) for 24 h, drought stress for 1h, and salt stress for 12 h. KCT2 transcription was not affected by anoxia stress for 8h and was down-regulated with cold stress for 48 h. KCT2 was cloned for the first time from the genus Brassica. Expression analysis indicated that in the early stage of plant adaption to stress conditions KCT2 is up-regulated, which results in a stimulation of potassium transport.

A gene encoding mitogen-activated protein kinase was isolated from oilseed rape (Brassica napus) following drought treatment. The cloned gene, designated as BnMPK3 (GenBank accession no. AY642433 ), contains one phosphorylation motif (TEY) and a conserved CD domain in its C-terminal extension. BnMPK3 is highly homologous to AtMPK3 gene from Arabidopsis thaliana and belongs to the A-subgroup of mitogen-activated protein kinase. Semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) analyses showed that the expression level of BnMPK3 transcript was up-regulated by mannitol, NaCl, cold, H2O2, abscisic acid (ABA), salicylic acid (SA) and methyl jasmonate acid (m-JA). Interestingly, SA, m-JA enhanced gradually BnMPK3's expression all along after 20–60 min treatment, but its expression was all initiated by mannitol, NaCl, H2O2 and ABA in a short time and reached the highest level after 1–2 h treatment. Hysteresis of cold response showed that BnMPK3's expression was initiated after 1 h from normal growth conditions at room temperature to 4 °C, and reached the highest level after 6 h treatment. The inhibitors of MAPK activation PD98059 and U0126 did not inhibit BnMPK3 transcript. BnMPK3 was cloned into pYES2.1 and transformed into yeasts, and BnMPK3's expression enhanced yeasts’ resistance to mannitol and peroxide in 600 mM mannitol and 0.2 mM tBuOOH drug assays. The present studies show that BnMPK3 is an early response gene involved in responses to biotic and abiotic stresses.

Bolting reduces the commercial value of Chinese cabbage, so inhibiting Chinese cabbage from bolting is important. Flowering locus C (FLC), a repressor of flowering, encodes a MADS-domain transcription factor in Arabidopsis thaliana. Here we report on the cloning and characterization of a FLC homologous gene from Chinese cabbage (designated as BrpFLC, GenBank accession number: AY364013) using RACE-PCR. The full-length cDNA of BrpFLC was 851 base pair (bp) and contained a 591 bp open reading frame (ORF) encoding a protein with 197 amino acid residues. The BrpFLC gene had a high degree of similarity to Brassica napus MADS-box protein mRNA (AY036890) and Brassica rapa cultivar samjin flowering locus C (FLC) mRNA (AY273162). Southern blot analysis indicated that the FLC gene belonged to a multi-gene family when the coding sequence of BrpFLC was used as a probe, and there was a single copy when a 3′ UTR region was used as a probe. Northern blot analysis using the 3′ UTR of BrpFLC as the probe revealed that the transcript level of BrpFLC of different anti-bolting Chinese cabbage cultivars was reduced by vernalization at different degrees, and the BrpFLC transcript levels of anti-bolting cultivars remained higher than those of easy bolting cultivars after vernalization, implying that the degree of vernalization sensitivity of the BrpFLC gene was related to the level of bolting of Chinese cabbage.

A full-length cDNA encoding taxadienol acetyl transferase (designated as TmTAT), that catalyzes the first acylation step in Taxol biosynthesis, was cloned from young leaves of Taxus x media by rapid amplification of cDNA ends (RACE). The full-length cDNA of TmTAT was 1459 bp and contained a 1317-bp open reading frame (ORF) encoding a protein of 439 amino acids. The deduced protein had a calculated molecular weight of about 49 kDa and an isoelectric point (pI) of 5.3, similar to acetyl transferases from Taxus cuspidata and Taxus chinensis. Sequence comparison analysis revealed that the TmTAT had high similarity with other members of plant transferase family. Phylogenetic tree analysis showed that TmTAT had close relationship with acetyl transferases from T. chinenisis and T. cuspidata. Tissue expression pattern analysis revealed that TmTAT expressed strongly in leaves, weak in stems and no expression could be detected in fruits, indicating that TmTAT was a tissue-specific gene.