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This paper investigates the economic value of online reviews for consumers and restaurants. We use a data set from Dianping.com, a leading Chinese website providing user-generated reviews, to study how consumers learn, from reading online reviews, the quality and cost of restaurant dining. We propose a learning model with three novel features: (1) different reviews offer different informational value to different types of consumers; (2) consumers learn their own preferences, and not the distribution of preferences among the entire population, for multiple product attributes; and (3) consumers update not only the expectation but also the variance of their preferences. Based on estimation results, we conduct a series of counterfactual experiments and find that the value from Dianping is about 7 CNY for each user, and about 8.6 CNY from each user for the reviewed restaurants in this study. The majority of the value comes from reviews on restaurant quality, and contextual comments are more valuable than numerical ratings in reviews. [ABSTRACT FROM AUTHOR]

This study developed a new method for the analysis of 20 phenolic compounds in human urine. The urine samples were prepared by hydrochloric acid (HCl) hydrolysis, liquid–liquid extraction (LLE), and solid-phase extraction (SPE) cleanup. We found that HCl hydrolysis is of similar effectiveness to, and much cheaper than, the traditional enzymatic method. Vanillic acid was co-eluted with butyl paraben and interfered with the determination of butyl paraben in urine. K2CO3-treated-silica-gel SPE was designed to efficiently eliminate interference from the endogenous organic acids (especially vanillic acid) in urine. After derivatization, the samples were analyzed by large-volume-injection gas chromatography–tandem mass spectrometry (LVI-GC–MS–MS). Good linearity (R 2 ≥ 0.996) was established in the range 0.1–100 ng mL−1 for all analytes. Method detection limits (MDLs) were 0.7–9.8 pg mL−1. Intraday (n = 5) and interday (n = 5 days) validation was performed, with satisfactory accuracy (recovery: 70–126 % and 73–107 %, respectively) and precision (RSD ≤ 19 %) at two levels (low: 0.1 and 0.5 ng mL−1; high: 5 and 10 ng mL−1). The method was used in a population study and achieved more than 85 % detection for most analytes; mean analyte concentrations were in the range 0.01–185 ng mL−1. The method is suitable for the analysis of multiple phenolic metabolites in human urine. [ABSTRACT FROM AUTHOR]

Background: Over the last decade, several studies have identified quantitative trait loci (QTL) affecting variation of immune related traits in mammals. Recent studies in humans and mice suggest that part of this variation may be caused by polymorphisms in genes involved in Toll-like receptor (TLR) signalling. In this project, we used a comparative approach to investigate the importance of TLR-related genes in comparison with other immunologically relevant genes for resistance traits in five species by associating their genomic location with previously published immune-related QTL regions. Results: We report the genomic localisation of TLR1-10 and ten associated signalling molecules in sheep and pig using in-silico and/or radiation hybrid (RH) mapping techniques and compare their positions with their annotated homologues in the human, cattle and mouse whole genome sequences. We also report medium-density RH maps for porcine chromosomes 8 and 13. A comparative analysis of the positions of previously published relevant QTLs allowed the identification of homologous regions that are associated with similar health traits in several species and which contain TLR related and other immunologically relevant genes. Additional evidence was gathered by examining relevant gene expression and association studies. Conclusion: This comparative genomic approach identified eight genes as potentially causative genes for variations of health related traits. These include susceptibility to clinical mastitis in dairy cattle, general disease resistance in sheep, cattle, humans and mice, and tolerance to protozoan infection in cattle and mice. Four TLR-related genes (TLR1, 6, MyD88, IRF3) appear to be the most likely candidate genes underlying QTL regions which control the resistance to the same or similar pathogens in several species. Further studies are required to investigate the potential role of polymorphisms within these genes. [ABSTRACT FROM AUTHOR]

The use of weeds to eliminate pollutants from agroecosystem has been considered recently. This study examined the ability of 17 weed species and 5 weed species combinations to accumulate lead (Pb) in polluted soil in greenhouse. The biomass production of all weed species used in this experiment was not affected by Pb in the polluted soil (334±22 Pb mg/kg soil) compared with growth in unpolluted soil (23±1 mg Pb/kg soil). Lead was accumulated mainly in roots of most weed species except Kummerowia striata, Ixeris chinensis, Digitaria ciliaris, Echinochloa crugalli var. mitis that largely accumulated Pb in their shoots. Total Pb accumulation of weed communities with four or six species were higher than that with two or eight species. Total Pb accumulation increased with enhancing biomass of weed communities. [ABSTRACT FROM AUTHOR]

Background: Aconitum transsectum Diels. (Ranunculaceae) is an important medicinal plant that is widely used in traditional Chinese medicine, but its morphological traits make it difficult to recognize from other Aconitum species. No research has sequenced the chloroplast genome of A.transsectum, despite the fact that phylogenetic analysis based on chloroplast genome sequences provides essential evidence for plant classification. Results: In this study, the chloroplast (cp) genome of A. transsectum was sequenced, assembled, and annotated. A. transsectum cp genome is a 155,872 bp tetrameric structure including a large single copy (LSC, 87,671 bp) and a small single copy (SSC, 18,891 bp) section, as well as a pair of inverted repeat sequences (IRa and IRb, 25,894 bp each). 131 genes are encoded by the complete cp genome, comprising 86 protein-coding genes, 37 tRNAs, and 8 rRNAs. The most favored codon in the A. transsectum cp genome is AUG, and 46 repeats and 241 SSRs were also identified. The A. transsectum cp genome is similar in size, gene composition, and IR expansion and contraction to the cp genomes of seven Ranunculaceae species. Phylogenetic analysis of cp genomes of 28 plants from the Ranunculaceae family shows that A. transsectum is most closely related to A. vilmorinianum, A. episcopale, and A. forrestii of Subgen. Aconitum. Conclusions: Overall, this study provides complete cp genome resources for A. transsectum that will be beneficial for identifying potential. [ABSTRACT FROM AUTHOR]

A new organic-inorganic hybrid coordination compound ZnQS(en) ·2H2O (1) in which two different organic ligands, ethylenediamine (en) and 8-hydroxyquinoline-5-sulfonic acid (H2QS) coordinate with zinc ions, has been synthesized via the evaporation method and characterized by single crystal X-ray diffraction analysis, IR spectroscopy and thermogravimetric analysis (TGA). The structure solution showed that compound 1 displays a three-dimensional supramolecular network by synergic linkage of hydrogen and coordinated bonds. Moreover, compound 1 exhibits intense photoluminescence at 513 nm excited at 396 nm in the solid state at room temperature. [ABSTRACT FROM AUTHOR]

Sheep (Ovis aries) are a major source of meat, milk, and fiber in the form of wool and represent a distinct class of animals that have a specialized digestive organ, the rumen, that carries out the initial digestion of plant material. We have developed and analyzed a high-quality reference sheep genome and transcriptomes from 40 different tissues. We identified highly expressed genes encoding keratin cross-linking proteins associated with rumen evolution. We also identified genes involved in lipid metabolism that had been amplified and/or had altered tissue expression patterns. This may be in response to changes in the barrier lipids of the skin, an interaction between lipid metabolism and wool synthesis, and an increased role of volatile fatty acids in ruminants compared with nonruminant animals. [ABSTRACT FROM AUTHOR]