Bar-Coded Pyrosequencing Reveals the Responses of PBDE-Degrading Microbial Communities to Electron Donor Amendments

Polybrominated diphenyl ethers (PBDEs) can be reductively degraded by microorganisms under anaerobic conditions. However, little is known about the effect of electron donors on microbial communities involved in PBDEs degradation. Here we employed 454 Titanium pyrosequencing to examine the phylogenetic diversity, composition, structure and dynamics of microbial communities from microcosms under the conditions of different electron donor amendments. The community structures in each of the five alternate electron donor enrichments were significantly shifted in comparison with those of the control microcosm. Commonly existing OTUs between the treatment and control consortia increased from 5 to 17 and more than 50% of OTUs increased around 13.7 to 186 times at least in one of the microcosms after 90-days enrichment. Although the microbial communities at different taxonomic levels were significantly changed by different environmental variable groups in redundancy analysis, significant correlations were observed between the microbial communities and PBDE congener profiles. The lesser-brominated PBDE congeners, tri-BDE congener (BDE-32) and hexa-BDE, were identified as the key factors shaping the microbial community structures at OTU level. Some rare populations, including the known dechlorinating bacterium, Dehalobacter, showed significant positive-correlation with the amounts of PBDE congeners in the consortia. The same results were also observed on some unclassified bacteria. These results suggest that PBDEs-degrading microbial communities can be successfully enriched, and their structures and compositions can be manipulated through adjusting the environmental parameters

Comparison of Kalman Filters for Inertial Integrated Navigation

The current research on integrated navigation is mainly focused on filtering or integrated navigation equipment. Studies systematically comparing and analyzing how to choose appropriate integrated filtering methods under different circumstances are lacking. This paper focuses on integrated navigation filters that are used by different filters and attitude parameters for inertial integrated navigation. We researched integrated navigation filters, established algorithms, and examined the relative merits for practical integrated navigation. Some suggestions for the use of filtering algorithms are provided. We completed simulations and car-mounted experiments for low-cost strapdown inertial navigation system (SINS) to assess the performance of the integrated navigation filtering algorithms

Experimental Comparison Study on Cyclic Behavior of Coupled Shear Walls with Two-Level-Yielding Steel Coupling Beam and RC Coupling Beam

[EN] Coupled shear walls are widely used in high rise buildings, since they can not only provide efficient lateral stiffness but also behave outstanding energy dissipation ability especially for earthquake-resistance. Traditionally, the coupling beams are made of reinforced concrete, which are prone to shear failure due to low aspect ratio and greatly reduce the efficiency and ability of energy dissipation. For overcoming the shortcoming of concrete reinforced coupling beams (RCB), an innovative steel coupling beams called two-level-yielding steel coupling beam (TYSCB) is invented to balance the demand of stiffness and energy dissipation for coupled shear walls. TYSCBs are made of two parallel steel beams with yielding at two different levels. To verify and investigate the aseismic behaviour improvement of TYSCB-coupled shear walls, two 1/3 scale, 10-storey coupled shear wall specimens with TYSCB and RCB were tested under both gravity and lateral displacement reversals. These two specimens were designed with the same bearing capacity, thus to be easier to compare. The experimental TYSCB specimen demonstrated more robust cyclic performance. Both specimens reached 1% lateral drift, however, the TYSCB-coupled shear wall showed minimal strength degradation. Additionally, a larger amount of energy was dissipated during each test of the TYSCB specimen, compared with the RCB specimen. Based on the experimental results, design recommendations are provided.The work presented in this paper was supported by the Ministry of Science and Technology of China through the Thirteen Five Key Research & Development Scheme with Grant 2016YFC0701203.Pang, M.; Li, G.; Sun, F.; Li, L.; Sun, J. (2018). Experimental Comparison Study on Cyclic Behavior of Coupled Shear Walls with Two-Level-Yielding Steel Coupling Beam and RC Coupling Beam. En Proceedings of the 12th International Conference on Advances in Steel-Concrete Composite Structures. ASCCS 2018. Editorial Universitat Politècnica de València. 733-738. https://doi.org/10.4995/ASCCS2018.2018.7026OCS73373

Lactobacillus gasseri RW2014 Ameliorates Hyperlipidemia by Modulating Bile Acid Metabolism and Gut Microbiota Composition in Rats

Hyperlipidemia is a leading risk of cardiovascular and cerebrovascular disease. Dietary supplementation with probiotics has been suggested as an alternative intervention to lower cholesterol. In the current study, we isolated a strain of Lactobacillus gasseri RW2014 (LGA) from the feces of a healthy infant fed with breast milk, and it displayed bile salt hydrolase (BSH) activity. Using this strain we determined its cholesterol-lowering and fatty liver-improving functions. SD rats were randomly divided into four groups. The control rats were fed a commercial chow diet and the other three groups were fed a high-fat diet (HFD) for a 7-week experiment period. After two weeks of feeding, the rats in PBS, simvastin, and LGA group were daily administered through oral gavage with 2 mL PBS, simvastin (1 mg/mL), and 2 × 109 CFU/mouse live LGA in PBS, respectively. After five weeks of such treatment, the rats were euthanized and tissue samples were collected. Blood lipid and inflammatory factors were measured by ELISA, gut microbiota was determined by 16S rRNA sequencing, and bile acids profiles were detected by metabolomics. We found that LGA group had lower levels of blood cholesterol and liver steatosis compared to the simvastin group. LGA also significantly reducedthe levels of inflammatory factors in the serum, including TNFα, IL-1β, MCP-1, IL-6, and exotoxin (ET), and increased the levels of short-chain fatty acids in feces, including isobutyric acid, butyric acid, isovaleric acid, valeric acid, and hexanoic acid. In addition, LGA altered the compositions of gut microbiota as manifested by the increased ratio of Firmicutes/Bacteroides and the relative abundance of Blautia genus. Targeted metabolomics results showed that bile acids, especially free bile acids and secondary bile acids in feces, were increased in LGA rats compared with the control rats. Accordingly, the rats administrated with LGA also had a higher abundance of serum bile acids, including 23-norcholic acid, 7-ketolithocholic acid, β-muricholic acid, cholic acid, and deoxycholic acid. Together, this study suggests that LGA may exert a cholesterol-lowering effect by modulating the metabolism of bile acids and the composition of gut microbiota

Loading and sustained release of sodium alginate membranes on pyridirubicin chloride

To develop diversified drug carriers for local treatment of cancer, three types of alginate membranes were fabricated by spin-coating, freeze drying and electrospinning. The uniaxial tensile test is shown that spin-coated membranes possess the maximum tensile strength. All the three types of membranes present excellent adsorption performance toward pyridirubicin chloride (THP) and the electrospinning membranes exhibit the maximum adsorption mass of 144.13 mg g ^−1 . The pseudo-first order, pseudo-second order, and intra-particle diffusion equation were used to evaluate the kinetic data and the drug adsorption process followed the pseudo-first-order model well. The drug releasing mechanism was studied by using different release medium, and it shows that the release process was undertaken by ions exchange reaction. The result shows that the three types of membranes are promising materials for the local treatment of cancer such as local cancers of the pancreas and trachea

High-Accuracy Calibration Based on Linearity Adjustment for Eddy Current Displacement Sensor

High precision position control is essential in the process of parts manufacturing and assembling, where eddy current displacement sensors (ECDSs) are widely used owing to the advantages of non-contact sensing, compact volume, and resistance to harsh conditions. To solve the nonlinear characteristics of the sensors, a high-accuracy calibration method based on linearity adjustment is proposed for ECDSs in this paper, which markedly improves the calibration accuracy and then the measurement accuracy. After matching the displacement value and the output voltage of the sensors, firstly, the sensitivity is adjusted according to the specified output range. Then, the weighted support vector adjustment models with the optimal weight of the zero-scale, mid-scale and full-scale are established respectively to cyclically adjust the linearity of the output characteristic curve. Finally, the final linearity adjustment model is obtained, and both the calibration accuracy and precision are verified by the established calibration system. Experimental results show that the linearity of the output characteristic curve of ECDS adjusted by the calibration method reaches over 99.9%, increasing by 1.9–5.0% more than the one of the original. In addition, the measurement accuracy improves from 11–25 μ m to 1–10 μ m in the range of 6mm, which provides a reliable guarantee for high accuracy displacement measurement

Associations between apolipoprotein B and bone mineral density: a population-based study

Abstract Background Lipids are critical in bone metabolism, and several studies have highlighted their importance. This study aimed to investigate the relationship between apolipoprotein B (apo B) and bone mineral density (BMD) at different skeletal sites (lumbar spine, femoral neck, and total femur) and to compare the influence of apo B with other traditional lipid markers. Methods The study included participants from the National Health and Nutrition Examination Survey (NHANES) between 2011 and 2016 who had complete data for apo B and BMD at the three skeletal sites. We used weighted multivariate regression analysis, subgroup analysis, and interaction tests to examine associations. Restricted cubic spline (RCS) was used to examine the non-linear relationship. Results A total of 4,258 adults were included in the study. Multivariate linear regression analysis showed that the relationship between apo B and BMD varied by skeletal site: a negative association was found with lumbar spine BMD [β = -0.054, 95%CI: (-0.073, -0.035)]. In contrast, a positive association was found with femoral neck BMD [β = 0.031, 95%CI: (0.011, 0.051)] and no significant association between apo B and total femur BMD. Conclusions Our findings suggest that apo B is associated with BMD in a site-specific manner