Arsenic pollution, geochemical fractions, and leaching characteristics in soil samples from four contaminated sites in the Beijiang River Basin, South China.

To remediate historically polluted sites before their land-use changes, it is essential to understand the concentration distribution, geochemical fraction, and migratory behavior of As in soil with varied particle sizes for the use of a sieving procedure. This study investigated the amount and percentage of As in soil with different particle sizes (0.25, 0.25-1, and 1-2 mm) as well as its toxicity characteristic in leaching procedure at four previously contaminated sites in the Beijiang River Basin, South China. The results showed that the total As concentration in the collected soils ranged from 70.1 to 402.8 mg/kg, and only a few percent of soil particle samples had As contents below the local risk threshold value of 60 mg/kg. The amorphous hydrous oxide bound, crystalline hydrous oxide bound, and residual fractions (F3-F5) of the geochemical fraction of As in soil of polluted sites accounted for 82.2-95.7% of the total As distribution. However, the concentration of As in non-specifically bound fractions increased with the mass ratio of soil with coarse particle sizes due to the negative correlation of Fe-bearing minerals concentration with the mass ratio of soil with coarse particle size. According to redundancy analysis, soil with coarse particle sizes and non-specifically bound As were mostly responsible for the As concentration in the leachate. These findings confirmed that a sieving process was not suitable for the remediation of soil As at four historically contaminated sites in the Beijiang River Basin due to the high concentration of As in soil and non-negligible environmental risk of labile extractable As in soil with coarse particle size.

A Novel Experiment Setting for Cross-subject Emotion Recognition.

Recently, cross-subject emotion recognition attracts widespread attention. The current emotional experiments mainly use video clips of different emotions as stimulus materials, but the videos watched by different subjects are the same, which may introduce the same noise pattern in the collected data. However, the traditional experiment settings for cross-subject emotion recognition models couldn't eliminate the impact of same video clips on recognition results, which may lead to a bias on classification. In this paper, we propose a novel experiment setting for cross-subject emotion recognition. We evaluate different experiment settings on four public emotion datasets, DEAP, SEED, SEED-IV and SEED-V. The experimental results demonstrate the deficiencies of the traditional experiment settings and the advantages of our proposed experiment setting.

Sex Difference in Emotion Recognition under Sleep Deprivation: Evidence from EEG and Eye-tracking.

Many psychiatric disorders are accompanied with sleep abnormalities, having significant influence on emotions which might worsen the disorder conditions. Previous studies discovered that the emotion recognition task with objective physiological signals, such as electroencephalography (EEG) and eye movements, provides a reliable way to figure out the complicated relationship between emotion and sleep. However, both of the emotion and EEG signals are affected by sex. This study aims to investigate how sex differences influence emotion recognition under three different sleep conditions. We firstly developed a four-class emotion recognition task based on various sleep conditions to augment the existing dataset. Then we improved the current state-of-the-art deep-learning model with the attention mechanism. It outperforms the best model with higher accuracy about 91.3% and more stabilization. After that, we compared the results of the male and the female group given by this model. The classification accuracy of happy emotion obviously decreases under sleep deprivation for both males and females, which indicates that sleep deprivation impairs the stimulation of happy emotion. Sleep deprivation also notably weakens the discrimination ability of sad emotion for males while females maintain the same as under common sleep. Our study is instructively beneficial to the real application of emotion recognition in disorder diagnosis.

Experimental Study on Force Sensitivity of the Conductivity of Carbon Nanotubes-Modified Epoxy Resins.

The addition of a conductive material into polymer improves its mechanical properties, electrical properties and thermal conductivity and bestows it with good self-sensing and self-adjusting properties. In this study, carbon nanotubes-modified epoxy resins (CNTs-EP) were successfully prepared with good dispersion through the combined methods of three roller rolling, ultrasonic processing and adding surfactant. Tests were conducted to evaluate the resistivity of unloaded modified epoxy resins with different mixing amounts of carbon nanotubes (CNTs), to determine the conductive percolation threshold. On the basis of the test results, a series of monotonic and cyclic uniaxial tensile tests were then conducted to investigate the force sensitivity of the conductivity of epoxy resins modified with different mixing amounts of CNTs. The relationship between the stress and the resistivity under various mixing amounts was studied, indicating that the resistance response could play a good warning role on the damage of the modified polymer material.

[Construction of RNAi vectors for SmNAC1 transcription factors of Salvia miltiorrhiza using Gateway cloning technology].

NAC transcription factors involved in plant growth and development, as well as responses to biotic and abiotic stress. RNAi Vectors for SmNAC transcription factors of Salvia miltiorrhiza was constructed by using Gateway cloning technology, in order to further study the function of SmNAC1 transcription factor. According to Gateway cloning technology, the specific fragments of SmNAC1 containing attB adapter was amplified by PCR using ultra-fideling phusion polymerase of NEB. By the BP recombination reaction, the PCR product containing attB was transferred to an donor vector (pENTR/SD/D-TOPO). Finally, SmNACi specific gene was cloned into pK7GWIWG2D plant expression vectors by LR recombination reaction. Experimental results showed that Gateway cloning technology provide a rapid and highly efficient way to clone the interested gene.

[Optimization of expression and purification of recombinant Salvia miltiorrhiza WRKY1 protein in Escherichia coli].

WRKY transcription factor is one of the Zinc finger proteins which contains a highly conserved WRKY domain and is a family of the plant-specific transcription factor. The plasmid pET28a-SmWRKY1 harboring Salvia miltiorrhiza WRKY1 (SmWRKY1) gene was successfully transformed and expressed in Escherichia coli BL21 (DE3). The conditions on protein expression of SmWRKY1 in E. coli, including induction duration, temperature, IPTG concentration and the E. coli concentration were optimized. The results showed that the highest protein expression of SmWRKY1 was obtained at 24 hours after the E. coli was cultured in the presence of 0.2 mol x L(-1) IPTG at 20 degrees C with A600 values of 1.0-1.5. This recombinant histidine-tagged protein was expressed at 2.454 g x L(-1) as inclusion body, which was first extracted using urea, and then purified by Ni2+ affinity chromatography and identified by SDS-PAGE. The expression of SmWRKY1 in E. coli was further confirmed by western blotting analysis.

[Cloning and expression analysis of pathogenesis-related protein 1 gene of Panax notoginseng].

By reverse transcription-polymerase chain reaction (RT-PCR), an open reading frame of pathogenesis-related protein 1 (PR1) was isolated from Panax notoginseng and named as PnPR1. Molecular and bioinformatic analyses of PnPR1 revealed that an open reading frame of 501 bp was predicted to encode a 166-amino acid protein with a deduced molecular mass of 18.1 kD. Homology analysis showed that the deduced amino acid sequence of PR1 protein of Panax notoginseng had a high similarity with other higher plants had the same conservative structure domain of cysteine-rich secretory protein (CAP). The recombinant expressed plasmid pET28a(+)-PnPR1 was expressed in Escherichia coli BL21. The expression conditions were optimized by induction at different times, different temperatures, different IPTG concentrations and different giving times. The optimum expression condition was 0.4 mmol.L-1 IPTG at 28 degrees C for 20 h. The successful expression of PnPR1 provides some basis for protein purification and preparation of the monoclonal antibody.

[Cloning and bioinformatics analysis of ent-kaurene oxidase synthase gene in Salvia miltiorrhiza].

Based on the transcriptome database of Salvia miltiorrhiza, specific primers were designed to clone a full-length cDNA of ent-kaurene oxidase synthase (SmKOL) using the RACE strategy. ORF Finder was used to find the open reading frame of SmKOL cDNA, and ClustalW has been performed to analysis the multiple amino acid sequence alignment. Phylogenetic tree has been constructed using MEGA 5.1. The transcription level of SmKOL from the hairy roots induced by elicitor methyl jasmonate (MeJA) was qualifiedby real-time quantitative PCR. The full length of SmKOL cDNA was of 1 884 bp nucleotides encoding 519 amino acids. The molecular weight of the SmKOL protein was about 58.88 kDa with isoelectric point (pI) of 7.62. Results of real-time quantitative PCR analyses indicated that the level of SmKOL mRNA expression in hairy roots was increased by elicitor oMeJA, and reached maximum in 36 h. The full-length cDNA of SmKOL was cloned from S. miltiorrhiza hairy root, which provides a target gene for further studies of its function, gibberellin biosynthesis and regulation of secondary metabolites.

[Overexpression and RNAi vectors built for key secondary metabolic pathway genes PAL, HMGR, PGT of Arnebia euchroma].

Arnebia euchroma is the main source for medicinal herb Zicao. and its most important component shikonin compounds have high medicinal and industrial value. This research is aimed to build overexpression vectors and RNAi vectors for key secondary metabolism genes of A. euchroma, and bulid platform for constructions of related transgenic lines using GATEWAY technology. To build genetic material based genetic research platform is to provide a great convenience for digging and functional verification of the genes on secondary metabolic pathway, and also to fill the gaps in transgenic research of A. euchroma. This study is also important for the cultivation of shikonin high-yielding strains of A. euchroma.

[Characterizing composition and transformation of dissolved organic matter in subsurface wastewater infiltration system].

In the present study, the soil column with radius of 30 cm and height of 200 cm was used to simulate a subsurface wastewater infiltration system. Under the hydraulic loading of 4 cm x d(-1), composition and transformation of dissolved organic matter (DOM) from different depths were analyzed in a subsurface wastewater infiltration system for treatment of septic tank effluent using three-dimensional excitation emission matrix fluorescence spectroscopy (3D-EEM) with regional integration analysis (FRI). The results indicate that: (1) from different depth, the composition of DOM was also different; influent with the depth of 0.5 m was mainly composed of protein-like substances, and that at other depths was mainly composed of humic- and fulvic-like substances. (2) DOM stability gradually increased and part of the nonbiodegradable organic matter can be removed during organic pollutants degradation process. (3) Not only the organic pollutants concentration was reduced effectively, but also the stability of the DOM improved in subsurface wastewater infiltration system.

A 12-year cohort study on the efficacy of plasma-derived hepatitis B vaccine in rural newborns.

AIM:To understand the anti HBs persistence and the long-term preventive efficacy in rural newborns after vaccination with plasma-derived hepatitis B vaccine.METHODS:In the time of expanded program on immunization (EPI), the newborns were vaccinated with 10&mgr;gcenter dot3 doses of hepatitis B vaccine and 762 newborns who were HBsAg negative after primary immunization were selected for cohort observation from 1986 to 1998. Their serum samples were detected qualitatively and quantitatively for hepatitis B infecting markers, including HBsAg, anti-HBs and anti-HBc by SPRIA Kits. The annual HBsAg positive conversion rate was counted by life-table method.RESULTS:(1)The anti-HBs positive rate was 94.44% for the babies born to HBsAg negative mothers and 84.21% for those born to HBsAg positive mothers in the 1st year after immunization, and dropped to 51.31% and 52.50% in the 12th year respectively.GMT value was dropped from 31.62 to 3.13 and 23.99 to 3.65 in the 2nd to the 12th year respectively. There was a marked drop in GMT at the 3rd to the 5th year, and in anti HBs positive rate at the 9th to the 10th year. (2) In the period of 12 years observation, the person-year HBsAg positive conversion rates were 0.12% (5/4150.0) in newborns born to HBsAg negative mothers and 0.20% (1/508.0) in those born to HBsAg positive mothers, and none of the HBsAg positive converted children became HBsAg chronic carriers. Compared with the baseline before immunization, the protective rates were 97.19% and 95.32% respectively.CONCLUSION:The protective efficacy of plasma-derived hepatitis B vaccine persisted at least 12 years, and a booster dose seems not necessary within at least 12 years after the primary three-doses immunization to newborns born to HBsAg negative mothers.