Observation of Fluctuation Spin Hall Effect in Antiferromagnet

The spin Hall effect (SHE) can generate a pure spin current by an electric current, which is promisingly used to electrically control magnetization. To reduce power consumption of this control, a giant spin Hall angle (SHA) in the SHE is desired in low-resistivity systems for practical applications. Here, critical spin fluctuation near the antiferromagnetic (AFM) phase-transition is proved as an effective mechanism to create an additional part of SHE, named as fluctuation spin Hall effect (FSHE). This FSHE enhances the SHA due to the AFM spin fluctuation between conduction electrons and local spins. We detect the FSHE with the inverse and direct spin Hall effect (ISHE and DSHE) set-up and their temperature (T) dependences in the Cr/MgO/Fe magnetic tunnel junctions (MTJs). The SHA is significantly enhanced when temperature is approached to the N\'eel temperature (T_N) and has a peak value of -0.34 at 200 K near T_N. This value is higher than the room-temperature value by 240% and comparable to that of heavy metals Ta and W. Furthermore, the spin Hall resistivity of Cr well fits the modeled T-dependence when T approaches T_N from low temperatures, implying the AFM spin fluctuation nature of strong SHA enhancement. Thus, this study demonstrates the critical spin fluctuation as a prospective way of increasing SHA and enriches the AFM material candidates for spin-orbitronic devices.Comment: 27 pages, 9 figure

The Research Advances of Bioremediation Technology on the Petroleum Pollution Treatment

Petroleum pollution has become a well concerned environmental problem. Renovating and controlling the petroleum pollution is an important guarantee to recover the environmental function. In recent years, the effect of bioremediation technology in eliminating petroleum pollution has been concerned by people gradually, of which, the effect of microorganism is the most important part. The paper discusses the source of petroleum pollution, the hazard of petroleum pollution, bioremediation mechanism and bioremediation technology of petroleum pollution and prospects the development trend and application of microorganism in renovating water in the petroleum pollution

The Research Advances of Bioremediation Technology on the Petroleum Pollution Treatment

Petroleum pollution has become a well concerned environmental problem. Renovating and controlling the petroleum pollution is an important guarantee to recover the environmental function. In recent years, the effect of bioremediation technology in eliminating petroleum pollution has been concerned by people gradually, of which, the effect of microorganism is the most important part. The paper discusses the source of petroleum pollution, the hazard of petroleum pollution, bioremediation mechanism and bioremediation technology of petroleum pollution and prospects the development trend and application of microorganism in renovating water in the petroleum pollution

Effects of seasonal variation in organic matter in groundwater on reactive nitrogen transport in the Jianghan Plain

Objective Dissolved organic matter (DOM) is an important carbon source in the biogeochemical process of groundwater. Methods To reveal the impact of the seasonal variation in DOM on the migration and transformation in groundwater on N in the Jianghan Plain, long-term water level and hydrochemical data of groundwater and surface water at the Shahu monitoring site were obtained, and the hydrogeochemistry analysis was carried out. The seasonal variation characteristics of DOM were analysed by combing with three-dimensional fluorescence spectroscopy and UV-V is spectroscopy, to explore the role of DOM in groundwater in N migration and transformation under the influence of hydrological conditions. Results The results show that DOM in groundwater and surface water includes three components: terrestrial humic-like component (C1), microbial tryptophan-like component (C2) and microbial humic-like component (C3). The input of microbial tryptophan-like components increases in dry season and terrestrial humic-like components increase in wet season. The strong reducibility and high dissolved organic carbon(DOC) content of groundwater provide conditions for the nitrate reduction, and low humification and low molecular weight C2 components are preferentially utilized in N migration and transformation. In dry season, the groundwater level decreases, the aquifer is partial to oxidation, the unstable protein-like components quickly degrade and release NH4-N, the nitrification and organic nitrogen mineralization rates are higher, and the denitrification and dissimilatory nitrite reduction to ammonium(DNRA) reaction rates are lower. In the wet season, the groundwater level rises, the aquifer tends to be reductive, and nitrification is inhibited. The presence of a large amount of DOM that is not easy to be degraded reduces the mineralization reaction rate of organic nitrogen in the aquifer, and the denitrification and DNRA processes are promoted. Conclusion In summary, the seasonal variation in DOM in the study area is an important factor in controlling the migration and transformation of N in groundwater

Effects of Exogenous Bacterial Agents on Material Transformation and Microbial Community Composition during Composting of Tomato Stalks

Tomato stems can pollute the environment and also cause resource costs. In this study, five combinations of microbial agents were added to tomato stems for aerobic composting to find effective microbial formulations to improve composting performance and product quality through comparative analysis. Six treatments were set up: T1 (Microbial agents A), T2 (0.5% Microbial agents B), T3 (0.5% Microbial agents C), T4 (0.5% Microbial agents D), T5 (0.5% Microbial agents E) and T6 (no addition). The physicochemical parameters of the composting system were measured, and the dynamics of the microbial community during the composting process were studied using high-throughput sequencing technology. The results showed that the T1 treatment had a longer high-temperature period than T6 and the highest cellulose degradation rate (62.0%). The contents of total phosphorus (TP), total potassium (TK) and effective potassium (AK) were 8.11 g·kg−1, 53.98 g·kg−1 and 45.62 g·kg−1, respectively, at the end of composting, representing increases of 270.3%, 56.6% and 25.40% compared to the initial values, significantly higher than the control (p p Aspergillus increased (4.13% to 44.24%) the abundance of Staphylococcus decreased (58.31% to 8.90%). In terms of numbers and species diversity, bacterial communities were more abundant than fungal communities. Proteobacteria, Firmicutes, Actinomycetes and Bacteroides were the four main bacterial phyla, while Ascomycetes was the absolutely dominant fungal phylum. In conclusion, the addition of microbial agent A can effectively improve the nutrient content of tomato stem compost, promote the maturation of compost, and regulate the microbial community structure and can realize the resource utilization of tomato stems

Prevalence of

The heartworm Dirofilaria immitis is the causative agent of cardiopulmonary dirofilariosis in dogs and cats, and also infects humans. However, there has been no study on dirofilariasis in dogs in central China. From March 2015 to February 2016, sera from 1176 randomly selected household dogs from Henan province, central China were examined for D. immitis antigen using the Canine Heartworm Antigen Test Kit. The overall seroprevalence of D. immitis in dogs in Henan province was 13% (155/1176). The prevalence was significantly higher in older dogs and dogs kept outdoors, compared to the younger ones and those sheltered indoors. No significant difference of prevalence was observed between sexes. The results suggest that the risk of exposure to D. immitis in dogs is high in Henan, and prophylaxis against the parasite is advisable to decrease the incidence of canine dirofilariosis in this region

Integrated Transcriptome and Metabolome Analysis Reveals an Essential Role for Auxin in Hypocotyl Elongation during End-of-Day Far-Red Treatment of Cucurbita moschata (Duch. Ex Lam.)

Long, robust hypocotyls are important for facilitating greenhouse transplant production. The use of far-red light at the end of the day (end-of-day far-red, EOD-FR) is known to prompt hypocotyl elongation, but the mechanism of EOD-FR-mediated hypocotyl elongation in pumpkin remains unclear. Here, we found that hypocotyl length, parenchymal cell size in hypocotyls, and plant IAA levels were significantly greater in pumpkin after EOD-FR treatment. This effect was counteracted by the application of the polar auxin transport inhibitor 1-N-naphthylphthalamic acid. Integrated transcriptomic and metabolomic analysis of pumpkin hypocotyls revealed that the expression of auxin-related genes changed significantly after EOD-FR treatment, and the contents of the auxin biosynthetic precursors tryptophan and indole were also significantly higher. Our results show that auxin plays an essential role in EOD-FR-mediated hypocotyl elongation, shed light on the mechanisms of EOD-FR mediated hypocotyl elongation, and provide a theoretical basis for the use of EOD-FR in facility cultivation

Prevalence of Dirofilaria immitis infection in dogs in Henan province, central China

The heartworm Dirofilaria immitis is the causative agent of cardiopulmonary dirofilariosis in dogs and cats, and also infects humans. However, there has been no study on dirofilariasis in dogs in central China. From March 2015 to February 2016, sera from 1176 randomly selected household dogs from Henan province, central China were examined for D. immitis antigen using the Canine Heartworm Antigen Test Kit. The overall seroprevalence of D. immitis in dogs in Henan province was 13% (155/1176). The prevalence was significantly higher in older dogs and dogs kept outdoors, compared to the younger ones and those sheltered indoors. No significant difference of prevalence was observed between sexes. The results suggest that the risk of exposure to D. immitis in dogs is high in Henan, and prophylaxis against the parasite is advisable to decrease the incidence of canine dirofilariosis in this region

Identification of Toxoplasma Gondii Tyrosine Hydroxylase (TH) Activity and Molecular Immunoprotection against Toxoplasmosis

The neurotropic parasite Toxoplasma gondii (T. gondii) infection can change the behavior of rodents and cause neuropsychological symptoms in humans, which may be related to the change in neurotransmitter dopamine in the host brain caused by T. gondii infection. T. gondii tyrosine hydroxylase (TgTH) is an important factor in increasing the neurotransmitter dopamine in the host brain. In this study, the enzyme activity of TgTH catalytic substrate for dopamine production and the molecular characteristics of TgTH were identified. In order to amplify the open reading frame (ORF), the designing of the specific primers for polymerase chain reaction (PCR) was on the basis of the TgTH sequence (GenBank Accession No. EU481510.1), which was inserted into pET-32a (+) for the expression of recombined TgTH (rTgTH). The sequence analysis indicated that the gene of TgTH directed the encoding of a 62.4-kDa protein consisting of 565 amino acid residues, which was predicted to have a high antigen index. The enzyme activity test showed that rTgTH and the soluble proteins extracted separately from T. gondii RH strain and PRU strain could catalyze the substrate to produce dopamine in a dose-dependent manner, and the optimum catalytic temperature was 37 °C. The result of the Western Blotting assay revealed that the rTgTH and the native TgTH extracted from somatic of T. gondii RH tachyzoite were successfully detected by the sera of mice infected with T. gondii and the rat serum after rTgTH immune, respectively. Immunofluorescence analysis using antibody against rTgTH demonstrated that the protein was expressed and located on the surface of T. gondii RH tachyzoite. Freund’s adjuvant was used to emulsify the rTgTH, which was subsequently applied to BALB/c mouse immune thrice on week 0, week 2, and week 4, respectively. The result of the animal challenge experiments showed an integral increase in IgG, IgG2a, IgG1, and IFN-γ, IL-4, and IL17 were as well significantly increased, and that the rTgTH vaccinated animals apparently had a prolonged survival time (14.30 ± 2.41) after infection with the RH strain of T. gondii compared with that of the non-vaccinated control animals, which died within 11 days. Additionally, in the rTgTH vaccination group, the number of brain cysts (1275 ± 224) significantly decreased (p < 0.05) compared to the blank control group (2375 ± 883), and the size of the brain cysts in the animals immunized with rTgTH vaccination was remarkably smaller than that of the control mice. All the findings prove that TgTH played an important role in increasing the neurotransmitter dopamine in the host brain and could be used as a vaccine candidate antigen to mediate cell-mediated and humoral immunity

Transcriptome and biochemical analyses reveal phenolic compounds-mediated flavor differences in loquat (Eriobotrya japonica Lindl.) cultivars Chunhua No.1 and Dawuxing

The novel loquat cultivar ‘Chunhua No.1′ (CH1) is a promising commercial cultivar. However, CH1 has texture characteristics different from those of common loquat, and its formation mechanism remains unclear. Here, we first identified the phenolic compounds of CH1 and its parent (‘Dawuxing’, DWX) and the effect on texture formation. The special presence of stone cells explained the flavor differences in CH1. Chlorogenic acid, neochlorogenic acid, and coniferyl alcohol were the main phenolic compounds in loquat, and the high content of coniferyl alcohol was a potential factor for the rough texture of CH1. Transcriptome reveals that phenylpropanoid metabolism was activated during CH1 fruit texture formation. Kyoto Encyclopedia of Genes and Genomes (KEGG) identified 51 structural genes involved in phenylpropanoid biosynthesis, and Weighted Gene Co-expression Network Analysis (WGCNA) identified four structural genes and 88 transcription factors. These findings provide new insights into the phenolic metabolism and flavor formation of loquat fruit