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The problem of selecting parameters for stochastic model updating is one that has been studied for decades, yet no method exists that guarantees the ‘correct’ choice. In this paper, a method is formulated based on global sensitivity analysis using a new evaluation function and a composite sensitivity index that discriminates explicitly between sets of parameters with correctly-modelled and erroneous statistics. The method is applied successfully to simulated data for a pin-jointed truss structure model in two studies, for the cases of independent and correlated parameters respectively. Finally, experimental validation of the method is carried out on a frame structure with uncertainty in the position of two masses. The statistics of mass positions are confirmed by the proposed method to be correctly modelled using a Kriging surrogate. [ABSTRACT FROM AUTHOR]

With the ability to generate in situ real-time electric signals, electrochemically active biofilm (EAB) sensors have attracted wide attention as a promising water biotoxicity early-warning device. Organic matters serving as the electron donors potentially affect the electric signal's output and the sensitivity of the EAB sensor. To explore the influence of organic matters on EAB sensor's performance, this study tested six different organic matters during the sensor's inoculation. Besides the acetate, a conventional and widely used organic matter, propionate and lactate were also found capable of starting up the sensor. Moreover, the propionate-fed (PF) sensor delivered the highest sensitivity, which are respectively 1.4 times and 2.8 times of acetate-fed (AF) sensor and lactate-fed (LF) sensor. Further analysis revealed that EAB of PF sensor had more vulnerable intracellular metabolism than the others, which manifested as the most severe energy metabolic suppression and reactive oxygen species attack. Regarding the microbial function, a two-component system that was deemed as an environment awareness system was found in the EAB of PF, which also contributed to its high sensitivity. Finally, PF sensor was tested in real water environment to deliver early-warning signals. • Effects of organic matters on the EAB sensors' sensitivity were investigated. • Propionate rather than acetate was suit for feeding sensitive sensors. • Energy metabolic suppression and ROS attack led to high sensitivity. • Microbial function difference was closely related to the sensitivity change. • Low concentration of propionate was more suit for high sensitivity. [ABSTRACT FROM AUTHOR]

Steroid hormones synthesized from cholesterol in the fetal adrenal are crucial for fetal development. We have observed the inhibited fetal adrenal corticosterone synthesis and increased intrauterine growth retardation (IUGR) rate in rats under prenatal caffeine ingestion. The aim of this study is to evaluate the effects of prenatal caffeine ingestion on cholesterol supply in fetal adrenal steroidogenesis in rats and explore the underlying epigenetic mechanisms. Pregnant Wistar rats were treated with 60 mg/kg·d caffeine from gestational day (GD) 7 to GD17. Histological changes of fetal adrenals and increased IUGR rates were observed in the caffeine group. There were significantly decreased steroid hormone contents and cholesterol supply in caffeine-treated fetal adrenals. Data from the gene expression array suggested that prenatal caffeine ingestion caused increased expression of genes related to DNA methylation and decreased expression of genes related to cholesterol uptake. The following conjoint analysis of DNA methylation array with these differentially expressed genes suggested that scavenger receptor class B type I (SR-BI) may play an important role in caffeine-induced cholesterol supply deficiency. Moreover, real-time RT-PCR and immunohistochemical detection certified the inhibitory effects of caffeine on both mRNA expression and protein expression of SR-BI in the fetal adrenal. And the increased DNA methylation frequency in the proximal promoter of SR-BI was confirmed by bisulfite-sequencing PCR. In conclusion, prenatal caffeine ingestion can induce DNA hypermethylation of the SR-BI promoter in the rat fetal adrenal. These effects may lead to decreased SR-BI expression and cholesterol uptake, which inhibits steroidogenesis in the fetal adrenal. [ABSTRACT FROM AUTHOR]

Angiotensin II (Ang II) induces cardiac hypertrophy and fibrosis in part by stimulating endothelin (ET-1) transcription. The involvement of the epigenetic machinery in this process is largely undefined. In the present study, we examined the epigenetic maneuvering underlying cardiac hypertrophy and fibrosis following ET-1 transactivation by Ang II. In response to Ang II stimulation, core components of the mammalian chromatin remodeling complex (Brahma-related gene 1, or Brg1, and Brahma or Brm) and histone H3K4 methylation complex (Ash2, absent, small, or homeotic discs 2, or Ash2 and WD domain repeat 5, or Wdr5) were recruited to the ET-1 promoter region in endothelial cells. Over-expression of Brg1/Brm or Ash2/Wdr5 enhanced while depletion of Brg1/Brm or Ash2/Wdr5 attenuated Ang II-induced ET-1 transactivation. Endothelial-specific knockdown of Brg1/Brm or Ash2/Wdr5 ameliorated cardiac hypertrophy both in vitro and in vivo . More important, Brg1/Brm interacted with Ash2/Wdr5 on the ET-1 promoter to catalyze H3K4 methylation. The crosstalk between Brg11/Brm and Ash2/Wdr5 was mediated by myocardin-related transcription factor A (MRTF-A). In conclusion, our data have unveiled an epigenetic complex that links ET-1 transactivation in endothelial cells to Ang II-induced cardiac hypertrophy and fibrosis. [ABSTRACT FROM AUTHOR]

Angiotensin II (Ang II) stimulates endothelin (ET-1) transcription, which contributes to cardiac hypertrophy and fibrosis. We have previously reported that myocardin related transcription factor A (MRTF-A) is indispensable for ET-1 transcription in vascular endothelial cells under hypoxic conditions, indicating that MRTF-A might mediate Ang II-induced pathological hypertrophy. Here we report that Ang II augmented the expression of MRTF-A in cultured endothelial cells and in the lungs of mice with cardiac hypertrophy. Over-expression of MRTF-A enhanced, whereas depletion of MRTF-A attenuated, transcriptional activation of ET-1 gene by Ang II. MRTF-A deficiency ameliorated Ang II induced cardiac hypertrophy and fibrosis in mice paralleling diminished synthesis and release of ET-1. Mechanistically, MRTF-A was recruited to the ET-1 promoter by c-Jun/c-Fos (AP-1) in response to Ang II treatment. Once bound, MRTF-A altered the chromatin structure by modulating histone acetylation and H3K4 methylation on the ET-1 promoter. More importantly, mice with endothelial-specific MRTF-A silencing by lentiviral particles phenocopied mice with systemic MRTF-A deletion in terms of Ang II-induced pathological hypertrophy. In conclusion, we data have unveiled a MRTF-A-containing complex that links ET-1 transactivation in endothelial cells to cardiac hypertrophy and fibrosis by Ang II. [ABSTRACT FROM AUTHOR]

Sepsis-associated encephalopathy (SAE) is a common complication of sepsis. Although sepsis is effectively managed with the administration of antibiotics and source control, which may include surgical intervention, SAE usually leads to prolonged cognitive dysfunction affecting the quality of life of the patients. In this study, we investigated the possible effect of electroacupuncture (EA) on cognition in a model of SAE induced by cecal ligation and puncture (CLP). The rats were randomly divided into four groups: the control group, the CLP group, the CLP with EA treatment group (CLP + EA), and the CLP with sham EA treatment group (CLP + sham EA). EA at DU20, LI11, and ST36 or sham EA was performed 30 min daily for 10 consecutive days starting from 2 days before CLP. Then cognitive function was examined by the Morris water maze test. On day 14 after CLP surgery, the synaptic injury, neuron loss, and oxidative stress were studied. Rats with EA treatment showed improved survival rate, spatial learning, and memory abilities. The dendritic spine density, the synaptic proteins, and the hippocampal neuron number were also increased after EA treatment. Furthermore, EA suppressed oxidative stress through regulating the level of malondialdehyde and superoxide dismutase and enhanced the expression of antioxidant nuclear factor erythroid-2–related factor-2 and hemeoxygenase-1. But sham EA did not have the same effect. EA may protect against SAE-induced cognitive dysfunction by inhibiting synaptic injury, neuronal loss, and oxidative stress, and the nuclear factor erythroid-2–related factor-2/hemeoxygenase-1 signaling pathway may be involved in this effect. [ABSTRACT FROM AUTHOR]

To investigate the effect of the organic loading rate (OLR) on anaerobic treatment of monosodium glutamate (MSG) wastewater, a lab-scale up-flow anaerobic blanket (UASB) reactor was continuously operated over a 222-day period. The overall performances of COD removal and methane recovery initially exhibited an increase and subsequently decreased when the OLR was increased from 1 g-COD/L/d to 24 g-COD/L/d. At the optimal OLR of 8 g-COD/L/d, superior performance was obtained with a maximum COD removal efficiency of 97%, a methane production rate of 2.3 L/L/d, and specific methanogenic activity of 86 mg-CH 4 /g-VSS/d (feeding on glutamate), with superior characteristics of sludge in VSS concentration, average diameter of granules, and settling velocity. According to the results of the specific methanogenic activity, the methanogenic pathway was more inclined to pass through acetate than through hydrogen. Methanosarcina instead of Methanosaeta , with Methanobacterium and greatly increased Firmicutes, dominated in the UASB reactor after long term operation. These results support that the OLR had a substantial effect on both the treatment and energy recovery efficiency of MSG wastewater as well as on microbial community variations in the UASB reactor. Image 1 • Methanogenic degradation of monosodium glutamate wastewater was validated. • Optimal COD removal and CH 4 recovery performance was obtained at OLR below 8 g/L/d. • Maximal glutamate removal capacity of the UASB reactor reached 18 g-COD/L/d. • Methanobacterium and Methanosarcina were dominated after long-term operation. • The OLR had a substantial impact on the microbial community variations in the UASB. [ABSTRACT FROM AUTHOR]

Cold treatment offers an effective avenue to preserve large yellow croaker fillets. However, the lipid distribution of fillets is unclear after cold treatments. This study aimed to identify differences of lipids among the fresh (RAW) and two cold treatments (− 1 ℃ and − 3 ℃) of large yellow croaker fillets using a lipidomics approach. A total of 2317 lipid species in RAW and two cold treatments were recognized and assigned to 13 sub-classes of lipids by using ultra-high-performance liquid chromatography-Q-exactive orbitrap mass spectrometry (UPLC-Q-Exactive Orbitrap MS) and lipidsearch software approach. Furthermore, there are 54 significantly different lipids were selected as potential lipid candidates of lipid oxidation of fillets by using correlation analysis between all individual lipids variables and freshness indicators (color, pH, thiobarbituric acid reactive substances, and total volatile bases nitrogen). All these potential candidates had involved 6 metabolic pathways that found the significant metabolic process on lipid oxidation after cold treatments. The autophagy-animal and glycerophospholipid metabolism were found to be two important pathways to analyze the lipids change, and were used to find the significant potential candidates of lipid oxidation on cold treatment. This work could provide a novel insight on the lipid changes analysis of large yellow croaker fillets after cold treatments. • Lipidomic changes of L. vannamei under low-temperature treatments was analyzed. • 417 individual lipids variables enriched in 6 metabolic pathways. • 54 significantly different lipids showing high correlation with freshness indicators. [ABSTRACT FROM AUTHOR]

The discovery of T4 DNA ligase in 1960s was pivotal in the spread of molecular biotechnology. The enzyme has become ubiquitous for recombinant DNA routinely practiced in biomedical research around the globe. Great efforts have been made to express and purify T4 DNA ligase to meet the world demand, yet over-expression of soluble T4 DNA ligase in E. coli has been difficult. Here we explore the use of adenylate kinase to enhance T4 DNA ligase expression and its downstream purification. E. coli adenylate kinase, which can be expressed in active form at high level, was fused to the N-terminus of T4 DNA ligase. The resulting His-tagged AK-T4 DNA ligase fusion protein was greatly over-expressed in E. coli , and readily purified to near homogeneity via two purification steps consisting of Blue Sepharose and Ni–NTA chromatography. The purified AK-T4 DNA ligase not only is fully active for DNA ligation, but also can use ADP in addition to ATP as energy source since adenylate kinase converts ADP to ATP and AMP. Thus adenylate kinase may be used as a solubility tag to facilitate recombinant protein expression as well as their downstream purification. [ABSTRACT FROM AUTHOR]

Large yellow croaker roe phospholipid (LYCRPLs) is a kind of multi-functional marine phospholipids. Advanced insights into its emulsifying properties and stability require a deeper exploring. In this study, the chemical composition of LYCRPLs, egg yolk phospholipids (EYPLs) and soybean phospholipids (SPLs) were determined, and their emulsifying properties were investigated systematically. Results suggested that the contents of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in LYCRPLs were the highest (39.35 ± 1.05%) and LYCRPLs had a different phospholipid composition compared with EYPLs and SPLs, but FTIR analysis shows there was no significant difference in the composition of the main functional groups among LYCRPLs, EYPLs and SPLs. Meanwhile, the initial astaxanthin nanoemulsions showed small particle size (0.23–0.27 μm) and had the lowest surface tension (34.29 ± 0.33 mN/m). Furthermore, LYCRPLs was the best one when they prevented nanoemulsions aggregation and phase separation. Findings indicate that LYCRPLs might be used as a reasonable emulsifier in the future. • The emulsifying properties of marine phospholipids from large yellow croaker roe were evaluated. • Large yellow croaker roe phospholipids are rich in EPA and DHA. • Lysophosphatidic of marine phospholipids may enhance its emulsifying properties. • The astaxanthin nanoemulsions stabilized by Large yellow croaker roe phospholipids has the best stability. [ABSTRACT FROM AUTHOR]

Nitrite-dependent anaerobic methane-oxidizing (n-damo) process has a promising prospect in anaerobic wastewater treatment, utilizing methane as the sole electron source to remove nitrite. However, the metabolic activity of n-damo bacteria is too low for practical application. This study aimed to stimulate n-damo process by introducing conductive nano-magnetite and/or electron shuttle anthraquinone-2,6-disulfonate (AQDS), and also set a comparative treatment of adding insulated ferrihydrite. The results showed that the nitrite reduction rate was enhanced the most significantly in treatment with nano-magnetite, approximately 1.6 times higher than that of the control without any supplement. While ferrihydrite application showed an adverse effect on n-damo process. The well-known aerobic methane oxidizer Methylomonas spp. was found to be enriched under n-damo condition with the supplementation of nano-magnetite and/or AQDS, but abundance of n-damo bacteria did not exhibit significant increase. It was hypothesized that Methylomonas spp. could be survived under anaerobic n-damo condition using oxygen produced by n-damo bacteria for the self-growth, and the nitrite reduction could be promoted through the enhancement of microbial interspecies electron transfer triggered by the introduction of conductive materials. It opens a new direction for the stimulation of n-damo activity, which needs more evidences to verify the hypothetic mechanism. • Nano-magnetite and/or AQDS stimulated the nitrite reduction of n-damo process. • Stimulation depended on acceleration of electron transfer via conductive materials. • N-damo pmoA and nod genes kept constant among different treatments. • Methylomonas was selectively enriched via nano-magnetite and/or AQDS. • A novel synergistic relationship of n-damo bacteria and Methylomonas was proposed. [ABSTRACT FROM AUTHOR]