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Cyanobacteria can perform both anoxygenic and oxygenic photosynthesis, a characteristic which ensured that these organisms were crucial in the evolution of the early Earth and the biosphere. Reactive oxygen species (ROS) produced in oxygenic photosynthesis and reactive sulfur species (RSS) produced in anoxygenic photosynthesis are closely related to intracellular redox equilibrium. ROS comprise superoxide anion (O2●−), hydrogen peroxide (H2O2), and hydroxyl radicals (●OH). RSS comprise H2S and sulfane sulfur (persulfide, polysulfide, and S8). Although the sensing mechanism for ROS in cyanobacteria has been explored, that of RSS has not been elucidated. Here, we studied the function of the transcriptional repressor PerR in RSS sensing in Synechococcus sp. PCC7002 (PCC7002). PerR was previously reported to sense ROS; however, our results revealed that it also participated in RSS sensing. PerR repressed the expression of prxI and downregulated the tolerance of PCC7002 to polysulfide (H2Sn). The reporter system indicated that PerR sensed H2Sn. Cys121 of the Cys4:Zn2+ site, which contains four cysteines (Cys121, Cys124, Cys160, and Cys163) bound to one zinc atom, could be modified by H2Sn to Cys121-SSH, as a result of which the zinc atom was released from the site. Moreover, Cys19 could also be modified by polysulfide to Cys19-SSH. Thus, our results reveal that PerR, a representative of the Cys4 zinc finger proteins, senses H2Sn. Our findings provide a new perspective to explore the adaptation strategy of cyanobacteria in Proterozoic and contemporary sulfurization oceans.

The spatial distribution of reactive silica (RSi) and organic carbon (OC) in the Bohai Sea was determined on the basis of field measurements, and budgets were calculated with support from literature data. The riverine input, primary production and water exchange between the Bohai Sea and Yellow Sea have a strong effect on the distributions of RSi and OC, with particularly high contents in sediments in the estuarine and mud areas in the Bohai Sea. Silica preservation in the sediment is more efficient than that of carbon. Exchanges via the Bohai Strait result in a net export of RSi and OC for the Bohai Sea. Increasing riverine inputs of RSi in the Bohai Sea due to water and sediment regulation since 2002 have induced a 10% increase in primary production. As a result, RSi has declined due to enhanced diatom growth and sedimentation. The Bohai Sea has thus shifted from a nitrogen to a silica limited ecosystem.

Fibroblast growth factor 21 (FGF21) is an endocrine hormone that regulates glucose, lipid, and energy homeostasis. While gene expression of FGF21 is regulated by the nuclear hormone receptor peroxisome proliferator-activated receptor alpha in the fasted state, little is known about the regulation of trafficking and secretion of FGF21. We show that mice with a mutation in the Yip1 domain family, member 6 gene (Klein-Zschocher [KLZ]; Yipf6 KLZ/Y ) on a high-fat diet (HFD) have higher plasma levels of FGF21 than mice that do not carry this mutation (controls) and hepatocytes from Yipf6 KLZ/Y mice secrete more FGF21 than hepatocytes from wild-type mice. Consequently, Yipf6 KLZ/Y mice are resistant to HFD-induced features of the metabolic syndrome and have increased lipolysis, energy expenditure, and thermogenesis, with an increase in core body temperature. Yipf6 KLZ/Y mice with hepatocyte-specific deletion of FGF21 were no longer protected from diet-induced obesity. We show that YIPF6 binds FGF21 in the endoplasmic reticulum to limit its secretion and specifies packaging of FGF21 into coat protein complex II (COPII) vesicles during development of obesity in mice. Levels of YIPF6 protein in human liver correlate with hepatic steatosis and correlate inversely with levels of FGF21 in serum from patients with nonalcoholic fatty liver disease (NAFLD). YIPF6 is therefore a newly identified regulator of FGF21 secretion during development of obesity and could be a target for treatment of obesity and NAFLD.

To investigate the source of Pb within Bohai Bay, Pb concentrations and Pb isotopic compositions (Pb-204, (206)pb, Pb-207, and Pb-208) of surface sediments in this area were determined. The Pb concentration in this bay varied widely from 6.9 to 39.2 mu g/g (average: 21.8 +/- 7.8 mu g/g), and the Pb isotopic compositions ranged from 0.8338 to 0.8864 (average: 2.0997 +/- 0.0180) for Pb-208/Pb-208 and from 2.0797 to 2.1531 (average: 0.8477 +/- 0.0135) for Pb-207/Pb-206, presenting in three distinct clusters. The Pb isotopic ratios of sediments from the northeastern (NE zone) and northwestern (NW zone) coastal areas were significantly influenced by anthropogenic sources such as coal combustion and automobile emission. In sediments from the central and southern Bohai Bay (C-S zone); however, Pb mainly originated from the Yellow River catchment, as a result of lithogenic sediment (from rock weathering) accumulation. The Pb isotopic ratios further indicate that, apart from riverine inputs, the neighboring large-scale ports and aerosols significantly contributed to the anthropogenic Pb contained in these sediments. Pb contamination in the Haihe and Luanhe river mouths as well as in the regions near ports is also suggested from anthropogenic enrichment factors. As cities and ports continue to develop around Bohai Bay, a long-term extensive sewage monitoring program is highly recommended. (C) 2015 Published by Elsevier Ltd.

As the last back-up supply of the nuclear power supply system, it is of great significance to ensure the safety and reliability of the nuclear emergency diesel power unit. For the emergency diesel generator set of nuclear power plant, the various signal types of diesel generator set are quasi periodic non-stationary signals, which make the diesel generator set have the characteristics of complex fault mechanism, difficult to collect and process all kinds of signals in a unified way, and difficult to extract fault features. The main purpose of this paper is to provide an early warning method and system for the coil temperature of diesel generator set in nuclear power station. By building a synchronous collection system for the coil temperature of diesel generator set, the collected coil temperature is counted in real time, and the abnormal analysis is carried out according to the real-time predicted value, and the early warning is carried out in time in case of any abnormality, so as to ensure the normal operation of diesel generator set.

The spatial distribution of reactive silica (RSi) and organic carbon (OC) in the Bohai Sea was determined on the basis of field measurements, and budgets were calculated with support from literature data. The riverine input, primary production and water exchange between the Bohai Sea and Yellow Sea have a strong effect on the distributions of RSi and OC, with particularly high contents in sediments in the estuarine and mud areas in the Bohai Sea. Silica preservation in the sediment is more efficient than that of carbon. Exchanges via the Bohai Strait result in a net export of RSi and OC for the Bohai Sea. Increasing riverine inputs of RSi in the Bohai Sea due to water and sediment regulation since 2002 have induced a 10% increase in primary production. As a result, RSi has declined due to enhanced diatom growth and sedimentation. The Bohai Sea has thus shifted from a nitrogen to a silica limited ecosystem.

Geochemical sources, spatio-temporal distribution, and associated environmental risk of Cd in the Bohai Sea were investigated using data from 405 surface sediment samples and two sediment cores. Local point Cd sources, TOC content, and currents are the main controlling factors of Cd distribution. The contribution of Cd from river discharge surpasses that from atmospheric deposition. Sediment-quality guidelines, enrichment factors, and chemical fraction analysis were used to assess metal toxicity in the collected sediments. Results show that Bohai Sea sediments have a moderate Cd enrichment level. This enrichment poses a high risk due to the relatively high mobility and bioavailability of Cd despite measured levels below sediment-quality guidelines at most stations. Vertical profiles of Cd concentrations, Al-normalized enrichment factors, and excess burial fluxes combined with 210Pb dating reveal the history of Cd pollution in the Bohai Sea over the last century. Data show Cd unvaried before the 1800s, a slight increase from the 1800s to the late 1950s, a decrease from the late 1960s to the 1970s, and an increase from the 1980s to 2001, including a relatively high value in 1998. Historic variation in Cd is closely associated with both natural and anthropogenic activities.

The distribution, sources, and fate of sedimentary thallium (Tl) in the Bohai Sea (BS) were studied on the basis of datasets of total Tl and chemical speciation of Tl in surface sediment samples. The Tl concentration exhibits a certain trend of accumulation in the fine-grained sediment, suggesting that the mud deposits are sinks for land-originated Tl and that the regional currents and tide systems play a key role in the sorting of sediment and accumulation of Tl in the BS. The low Tl enrichment factor and high proportion of Tl in the residual fraction indicated that Tl is mainly derived from a natural source, although the BS is under intense environmental pressure because of excess wastewater discharge. Local Tl contamination was observed at the Liuguhe River mouth, and this contamination does not extend to beyond the inner shelves of the BS because of the regional currents. The level of Tl in the nonresidual fraction is very low and is dominated by the level of Tl in the Fe-Mn oxide fraction, indicating that Tl exhibits low mobility and bioavailability in the BS. The correlations between Tl concentration and MnO and Fe2O3 and the relatively high level of Tl in Fe-Mn oxide fraction suggested that MnO and Fe2O3 influence the geochemical behavior of Tl in the BS. The oxidizable fraction of Tl is negligible, suggesting that total organic carbon (TOC) might not be a major factor influencing the accumulation of Tl in the BS, although there is a positive correlation between Tl and TOC in the samples.

In this paper, we research on the novel financial affairs evaluation methodology based on entropy value method and gray theory. Separate analysis of any financial indicators which are difficult to evaluate comprehensively the financial position and operating results of an enterprise. Grey fuzzy comprehensive evaluation can be understood as the known information under the premise of not fully judge things or phenomena with fuzzy factors. Our proposed approach could solve the existing drawbacks well. In the future, more corresponding research will be finalized.

As a consequence of anthropogenic perturbations the global ocean is warming, acidifying, losing oxygen and sea ice, and sea level is rising. While drastic reduction of the emission of greenhouse gases is urgently needed, which includes ocean energy substitution for fossil energy, we show that the ocean offers numerous opportunities to reduce the causes and consequences of climate change, globally and locally. A wide range of ocean-based measures to enhance societal climate adaptation are currently implemented worldwide to deal either with coastal risks or changes in ocean resources. Ocean-related measures should not be considered as a substitute for climate mitigation on land or non ocean-based adaptation measures, which must be strongly pursued for the benefit of the atmosphere, the ocean, and socio-ecological systems worldwide