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Dopamine (DA) neurons in the ventral tegmental area (VTA) are critical to coping with stress. However, molecular mechanisms regulating their activity and stress-induced depression were not well understood. We found that the receptor tyrosine kinase ErbB4 in VTA was activated in stress-susceptible mice. Deleting ErbB4 in VTA or in DA neurons, or chemical genetic inhibition of ErbB4 kinase activity in VTA suppressed the development of chronic social defeat stress (CSDS)-induced depression-like behaviors. ErbB4 activation required the expression of NRG1 in the laterodorsal tegmentum (LDTg); LDTg-specific deletion of NRG1 inhibited depression-like behaviors. NRG1 and ErbB4 suppressed potassium currents of VTA DA neurons and increased their firing activity. Finally, we showed that acute inhibition of ErbB4 after stress attenuated DA neuron hyperactivity and expression of depression-like behaviors. Together, these observations demonstrate a critical role of NRG1-ErbB4 signaling in regulating depression-like behaviors and identify an unexpected mechanism by which the LDTg-VTA circuit regulates the activity of DA neurons.

As tobacco waste production from tobacco industry increases, it becomes important to convert tobacco waste into high value-added products. In this paper, the production of aroma compounds from the fast pyrolysis of tobacco waste was investigated, two kinds of tobacco waste—tobacco leaf fragments (TF), tobacco stems (TS)—and Modeng-brand cigarette tobacco (MT) were used as raw materials in a fluidized bed pyrolysis reactor. Tobacco types, pyrolysis temperatures, and bio-oil separation methods were assigned as influence factors, and the type and content of bio-oil-containing aroma compounds were defined as evaluation standards. Our results indicate that (i) the bio-oil yield under the same pyrolysis temperature (350 °C) is TS > MT > TF; (ii) when TF and MT are used as raw materials, low-temperature (about 350 °C) pyrolysis is beneficial for the production of aroma compounds, whereas TS requires higher temperature (more than 380 °C) pyrolysis; and (iii) bio-oils obtained from different separation methods contain different kinds of aroma compounds, with some compounds requiring certain separation methods. The formation and pyrolysis mechanism of nitrogen (N)-containing compounds in tobacco was also studied. The study demonstrated that nicotine converts to N-containing heterocycles because of secondary decomposition under high temperature.

The decomposition of levulinic acid (LA) is a critical factor limiting the yield of LA produced by biomass hydrolysis. In this study, the effects of influencing factors, especially furfural, on the decomposition of LA were investigated. Results show that furfural, as a hemicellulose hydrolysis product, led to an increase in LA decomposition; 25.3% of LA decomposed when furfural concentration was 0.3 mol/L at 200 °C. Furthermore, sulfuric acid, as a hydrolysis catalyst, was found to have a synergistic effect with furfural on LA decomposition, giving a maximum promotion of 9.86% on LA decomposition compared with the effect of acid or furfural alone. A kinetic model of LA decomposition considering the synergistic effect of furfural and acid concentration was established, and the activation energy of LA decomposition was found to be 34.46 kJ/mol.

We describe several new aromatic nitrogen mustards with various aromatic substituents and boronic esters that can be activated with H2O2to efficiently cross-link DNA. In vitro studies demonstrated the anticancer potential of these compounds at lower concentrations than those of other clinically used chemotherapeutics, such as melphalan and chlorambucil. In particular, compound 10, bearing an amino acid ester chain, is selectively cytotoxic toward breast cancer and leukemia cells that have inherently high levels of reactive oxygen species. Importantly, 10was 10–14-fold more efficacious than melphalan and chlorambucil for triple-negative breast-cancer (TNBC) cells. Similarly, 10is more toxic toward primary chronic-lymphocytic-leukemia cells than either chlorambucil or the lead compound, 9. The introduction of an amino acid side chain improved the solubility and permeability of 10. Furthermore, 10inhibited the growth of TNBC tumors in xenografted mice without obvious signs of general toxicity, making this compound an ideal drug candidate for clinical development.

The 2016–2017 epidemic of influenza A (H7N9) virus in China prompted concern that a genetic change may underlie increased virulence. Based on an evolutionary analysis of H7N9 viruses from all five outbreak waves, we find that additional subclades of the H7 and N9 genes have emerged. Our analysis indicates that H7N9 viruses inherited NP genes from co-circulating H7N9 instead of H9N2 viruses. Genotypic diversity among H7N9 viruses increased following wave I, peaked during wave III, and rapidly deceased thereafter with minimal diversity in wave V, suggesting that the viruses entered a relatively stable evolutionary stage. The ZJ11 genotype caused the majority of human infections in wave V. We suggest that the largest outbreak of wave V may be due to a constellation of genes rather than a single mutation. Therefore, continuous surveillance is necessary to minimize the threat of H7N9 viruses.

Many viruses can cause respiratory diseases in humans. Although great advances have been achieved in methods of diagnosis, it remains challenging to identify pathogens in unexplained pneumonia (UP) cases. In this study, we applied next-generation sequencing (NGS) technology and a metagenomic approach to detect and characterize respiratory viruses in UP cases from Guizhou Province, China. A total of 33 oropharyngeal swabs were obtained from hospitalized UP patients and subjected to NGS. An unbiased metagenomic analysis pipeline identified 13 virus species in 16 samples. Human rhinovirus C was the virus most frequently detected and was identified in seven samples. Human measles virus, adenovirus B 55 and coxsackievirus A10 were also identified. Metagenomic sequencing also provided virus genomic sequences, which enabled genotype characterization and phylogenetic analysis. For cases of multiple infection, metagenomic sequencing afforded information regarding the quantity of each virus in the sample, which could be used to evaluate each viruses’ role in the disease. Our study highlights the potential of metagenomic sequencing for pathogen identification in UP cases.

In this paper, a novel region of interest (ROI) query method is proposed for image retrieval by combining a mean shift tracking (MST) algorithm and an improved expectation–maximisation (EM)-like (IEML) method. In the proposed combination, the MST is used to seek the initial location of the target candidate model and then IEML is used to adaptively change the location and scale of the target candidate model to include the relevant region and exclude the irrelevant region as far as possible. In order to improve the performance and effectiveness using IEML to track the target candidate model, a new similarity measure is built based on spatial and colour features and a new image retrieval framework for this new environment is proposed. Extensive experiments confirm that compared with the latest developed approaches, such as the generalized Hough transform (GHT) and EM-like tracking methods, our method can provide a much better performance in effectiveness. On the other hand, for the IEML, the new similarity measure model also substantially decreases computational complexity and improves the precision tracking of the target candidate model. Compared with the conventional ROI-based image retrieval methods, the most significant highlight is that the proposed method can directly find the target candidate model in the candidate image without pre-segmentation in advance. [ABSTRACT FROM AUTHOR]

The first organocatalytic diastereo and enantioselective Michael addition reaction of 4substitutedpyrazolin5ones to nitroolefins has been developed with a chiral bifunctional thiourea as organocatalyst. A wide variety of desired multisubstituted pyrazolin5one derivatives with contiguous quaternary and tertiary stereocenters are smoothly obtained in very good yields up to 98% with excellent enantioselectivities up to>99% ee and acceptable diastereoselectivities up to 80:20. This experimentally simple process facilitates the access to various enantioenriched, multiply substituted pyrazolin5one derivatives, potential biologically active molecules, starting from readily available starting materials.

The multiplex polymerase chain reaction (PCR) technique was applied to detect the SARS-CoV (severe acute respiratory syndrome-associated coronavirus) specific target cDNA fragments in the present study. The target cDNA fragments of SARS-CoV were synthesized artificially according to the genome sequence of SARS-CoV in GenBank submitted by The Chinese University of Hong Kong, and were used as simulated positive samples. Five primers recommended by World Health Organization (WHO) were used to amplify the fragments by single PCR and multiplex PCR. Three target cDNA fragments (121, 182 and 302 bp), as well as the three different combinations of any two of these fragments, were amplified by single PCR. The combination of these three fragments was amplified by multiplex PCR. The results indicated that the multiplex PCR technique could be applied to detect the SARS-CoV specific target cDNA fragments successfully.

Microbial strains capable of degrading petroleum hydrocarbons were isolated from the Yellow River Delta and screened for bio-surfactant production. The bio-surfactant-producing characteristics of the isolates were evaluated, and all the isolates which could produce bio-surfactant were identified by 16S rRNA gene sequencing. The results showed that the isolates belong to Bacillussp. (72%), Ochrobactrumsp. (0.16%), Brevundimonassp. (0.06%) and Brevibacteriumsp. (0.06%). The biodegradability of crude oil, gasoline, diesel oil and other hydrocarbons by microbial strains were studied, among which the biodegrading ability of strain P1 and strain P19 is higher than other strains. Both strains P1 and P19 can degrade n-hexane and n-hexadecane effectively and have wide substrate extensiveness. In addition, Ni promoted the biodegradability of toluene by both strain P1 and strain P19, while Pb inhibited the growth of strain P19 and decreased its ability to biodegrade toluene. The studies revealed that microbes including strain P1 and strain P19 can be utilized in bioremediation of co-contaminated water with petroleum and heavy metals including Ni and Pb.

• We propose the ELS-fbm model to price the equity-linked-security (ELS) option by the Monte Carlo simulation (MCS) method. • We use the classical ELS model and ELS-fBm model to price one-, two-, and three-asset respectively. • The long-range dependence is necessary and more suitable for the financial market under uncertain environment. • We show the efficiency of the proposed model by a real ELS product contract issued by Future Asset company. In this paper, we use the Monte Carlo simulation (MCS) method to price the Equity-Linked Securities (ELS) option by fractional Brownian motion (fBm). We use the fBm that satisfy the Itô process instead of the geometric Brownian motion, and we call the proposed model ELS-fBm model. We first do the convergence test with the number of MCS. Then, we price the one-, two-, and three-asset ELS by employing the classical ELS model and the ELS-fBm model, respectively. We see that the price of ELS varies with different Hurst exponent, which indicates that the ELS pricing model considering the long-range dependence is necessary and more suitable for the financial market under uncertain environment. In addition, we prove the superiority of our proposed model with an actual three-assets ELS product which is issued by Future Asset company. We find the ELS price calculated by the proposed ELS-fBm model almost the same as the ELS price in the ELS product contract issued by Future Asset company, while the classical ELS model produces a great deviation. [ABSTRACT FROM AUTHOR]