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To research the dynamic characteristics of Laminar Flow Meter (LFM) on millisecond scale, a test device based on the pVTt gas flow standard device with a high-speed electromagnetic valve for generating unsteady flow is designed. According to the parameters of the device and the predicted characteristics of unsteady flow test, a sheet-type LFM with a range of 10 NL/min is designed, the dynamic characteristics of which under step flow and pulsating flow excitations are researched. The time-domain analysis of LFM output under step flow excitation shows that the delay time is 24.9 ms, the rise time is 29.2 ms, and the adjustment time is 55.3 ms. The results of pulsation flow test show that the LFM can effectively measure the instantaneous flow waveform of pulsating flow and the differences of cumulative flow given by the LFM and the test device are less than ±2 %. This research explores a feasible method to trace the dynamic characteristics of the LFM to the SI units, which provides a very valuable reference for researchers who encounter difficulties in flow measurement of unsteady flow research. • To research the dynamic characteristics of LFM on millisecond scale, a test device based on the pVTt gas flow standard device with a high-speed electromagnetic valve for generating unsteady flow is designed. • The dynamic characteristics of LFM under step flow and pulsating flow excitations are researched. • This research explores a feasible method to trace the dynamic characteristics of the LFM to the SI units. [ABSTRACT FROM AUTHOR]

In recent years, the nephrotoxicity and carcinogenicity of aristolochic acid have attracted worldwide attention, and the traditional Chinese medicine containing this ingredient has been banned in many places, affecting the TCM industry. To meet this challenge, researchers have developed various detection methods, such as high-performance liquid chromatography, gas chromatography-mass spectrometry and thin-layer chromatography. A rapid detection method must therefore be developed to ensure safety. A polyclonal antibody capable of recognizing aristolochic acid was prepared, and an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) was established to detect the amount of aristolochic acid in the sample to be measured. Methods Using 1-(4-chlorophenyl) cyclobutylamine as a hapten, immunogens and coating antigens were obtained by coupling with bovine serum albumin (BSA) and chicken ovalbumin (OVA) using the active ester method. UV scanning confirmed the successful coupling of the conjugate, and New Zealand white rabbits were immunized. The obtained antibody serum was screened for the best antibody by ic-ELISA detection. Use the chessboard method to determine three optimal combinations of original coating concentration and antibody dilution ratio, establish a standard curve for each combination to obtain the best combination, and establish a rapid detection method. Finally, the standard aristolochic acid A was added to the purchased apple vinegar and canned coffee for recycling experiments to verify the detection method.By changing the antigen antibody concentration, the antibody showed the highest sensitivity to aristolochic acid standard at the original coating, 1000-fold dilution, IC 50 of 24.88 ng/mL, limit of detection IC 10 of 3.19 ng/mL, and detection range IC 20 -IC 80 of 6.81–90.91 ng/mL. The recovery experiments under this conditions yielded a recovery rate of 92%–105%, within reasonable limits, indicating the success of the ELISA rapid detection method. Conclusion The enzyme-linked immunoassay method established in this paper can quickly detect the content of aristolochic acid in the sample to be tested, and the antibody prepared by this method has good broad-spectrum and can detect other aristolochic acid, such as aristolochic acid A, aristolochic acid B, aristolochic acid C, and aristolochic acid D. [Display omitted] • A novel antigenic structure was obtained for the first time. • A homologous coating strategy resulted to a high sensitivity. • A highly sensitive and broadly specific competitive indirect enzyme-linked immunosorbent assay method was developed. [ABSTRACT FROM AUTHOR]

In the past, the PHB gene function was mainly focused on anti-cell proliferation and antitumor effects. But the molecular mechanism of the PHB gene regarding saline and oxidative stresses is unclear. To study the role of AtPHB6 in salt and oxidative stress, AtPHB6 was cloned from A. thaliana. Bioinformatics analysis showed that AtPHB6 was closely related to AtPHB1 and AtPHB2, which are both type II PHB. RT–qPCR results indicated that the AtPHB6 in the leaves and roots of A. thaliana was obviously induced under different stress treatments. AtPHB6- overexpressing plants were larger and more lush than wild-type and mutant plants when placed under stress treatments during seed germination. The root length and fresh weight of AtPHB6 transgenic plants showed the best resistance compared to wild-type plants under different treatments, in contrast, the AtPHB6 mutants had the worst resistance during the seedling stage. AtSOT12 was an interacting protein of At PHB6, which screened by yeast two-hybrid system. The interaction between the two proteins were further confirmed using in vitro pull-down experiments and in vivo BiFC experiments. Subcellular localization showed both AtPHB6 and AtSOT12 protein expressed in the nucleus and cytoplasm. The H 2 O 2 content in both the transgenic AtPHB6 and AtSOT12 plants were lower than that in the wild type under stresses. Thus, AtPHB6 increased plant resistance to salt stress and interacted with the AtSOT12 protein. • AtPHB6 was cloned from Arabidopsis thaliana , and we found that it was an important gene which highly sensitive to stress. • AtPHB6 transgenic Arabidopsis thaliana increased the tolerance to stresses than wild type, and the atphb6 mutant was the worst. • AtSOT12 is the interaction protein of AtPHB6, which was screened by yeast two-hybrid system. • The co-transformation of AtPHB6 and AtSOT12 was verified in yeast, and the interaction between them were further confirmed by vitro pull-down and BiFC experiments. [ABSTRACT FROM AUTHOR]

To achieve carbon neutrality quickly and deal with urban greenhouse effect, it is necessary to study the energy consumption of urban buildings. Energy consumption prediction is an important step in planning and managing energy use in buildings. At present, few studies have comprehensively considered the relationship between geometric features, functional types, location and energy use of buildings in urban built-up areas. In this paper, a spatial data-driven framework is introduced for the analysis and assessment of building energy consumption. The framework is grounded in the building centroid and is combined with single photon radar and point of interest data through the utilization of the nearest neighbor classification algorithm. Two megacities, Beijing and Shanghai, are taken as examples to illustrate the method and to generate the regional building energy use database. The results show that: a) building physical feature (geometric form, functional type) have a significant impact on energy consumption, and energy consumption is correlated with the economic level of the region; b) Energy use in urban built-up areas has obvious spatial agglomeration characteristics, and the siphon effect is obvious in region with high energy consumption. The contribution of the framework is to provide insights into the feasibility of employing multiple spatial data fusion for the analysis of energy consumption within urban built-up areas. This can be employed to address energy planning concerns and help promote sustainable environmental practices in urban areas worldwide. • This paper attempts to provide a feasible framework for analyzing urban building energy use by utilizing real-time urban semantic perception information and building features. • The proposed framework have comprehensively considered the relationship between geometric features, functional types, location and energy use of buildings. • The proposed methodology can obtain regional energy consumption stocks and produce spatial distribution results, thus improving the interpretability of the data. • The results show that energy use in urban built-up areas has obvious spatial agglomeration characteristics, and the siphoning effect is obvious in regions with high energy consumption. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNA DLX6 antisense RNA 1 (DLX6-AS1) has been reported to be involved in various human diseases, however, its potential role in the pathogenesis of preeclampsia (PE) has not been fully explored.Methods: The levels of DLX6-AS1, microRNA-149-5p (miR-149-5p) and endoplasmic reticulum protein 44 (ERP44) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). Some clinicopathological parameters of PE were statistically analyzed. The cell proliferation, invasion and angiogenesis were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT), transwell and tube formation assays, respectively. Levels of all protein were detected by western blot. The target relationship was predicted by StarBase v2.0 and confirmed by dual-luciferase reporter assay.Results: Higher levels of DLX6-AS1 and ERP44, lower level of miR-149-5p were observed in PE placenta tissues. Compared with PE group with low DLX6-AS1 expression, the systolic blood pressure, diastolic blood pressure and proteinuria levels in the group with high DLX6-AS1 expression were higher, and the infant body weight level was lower. The role of miR-149-5p on these clinicopathological parameters of PE patients was opposite to that of DLX6-AS1, while ERP44 had the same effect as DLX6-AS1. Besides, DLX6-AS1 directly targeted miR-149-5p and miR-149-5p targeted ERP44. The inhibitory impact of DLX6-AS1 overexpression or ERP44 overexpression on proliferation and invasion of trophoblast cells as well as angiogenesis of HUVEC cells was reversed by up-regulating miR-149-5p. We also found that DLX6-AS1 could enhance ERP44 expression by sponging miR-149-5p.Conclusion: DLX6-AS1 inhibited proliferation and invasion of trophoblast cells, and suppressed angiogenesis of HUVEC cells by miR-149-5p/ERP44 pathway. [ABSTRACT FROM AUTHOR]

• EBR delayed senescence of kiwifruit. • EBR regulated enzymes activity related to sugar metabolism. • EBR inhibited starch conversion and soluble sugar accumulation to extend shelf life. Effect of 5 μM 24-epibrassinolide (EBR) on delaying the senescence of 'Huayou' kiwifruit and possible defense mechanisms were elucidated during ambient storage. Results revealed that EBR treatment retarded decrease in firmness as well as increase in weight loss and total soluble solid content in kiwifruit. EBR treatment prevented the increase of membrane permeability and suppressed the accumulation of malondialdehyde. EBR treatment postponed the degradation of starch to soluble sugars, resulting from the inactivation of amylase activity. EBR treatment also inhibited the activity of acid invertase, neutral invertase, sucrose phosphate synthase, sucrose synthase, hexokinase and fructokinase, and subsequently EBR-treated fruit exhibited the lower contents of sucrose, glucose and fructose. These results suggest that EBR treatment could be an innovative solution to delay the senescence of kiwifruit by regulating sugar metabolism. [ABSTRACT FROM AUTHOR]

A novel ratiometric fluorescent probe was designed and synthesized for detection of bisulfite, via pyrene as an electron donor (D) and 4, 5-dibromothiophene as an electron acceptor (A). It had good selectivity, sensitivity and short response time. The fluorescence intensity ratio at 420 nm and 530 nm (I 420 /I 530 ) displayed a good linear relationship with the concentration of HSO 3 − in the range of 0–35 μM, and the detection limit was 0.77 μM. The possible recognition mechanism of probe and HSO 3 − was illustrated by NMR, HRMS and computational analysis. Notably, the probe was successfully applied for imaging HSO 3 − in A549 cells, Caenorhabditis elegans and zebrafish, which indicated that this probe had great potential for HSO 3 − detection in vivo. [ABSTRACT FROM AUTHOR]

[Display omitted] • Conversion of CO 2 to GlcNAc was achieved for the first time by engineered C. necator. • GlcNAc biosynthetic pathway was constructed by expression of Cegna1 *. • PHB synthesis pathway and ED pathway disruption increased the production of GlcNAc. • The maximum GlcNAc titer from CO 2 reached 75.3 mg/L. The conversion of CO 2 into valuable bioactive substances using synthetic biological techniques is a potential approach for mitigating the greenhouse effect. Here, the engineering of C. necator H16 to produce N -acetylglucosamine (GlcNAc) from CO 2 is reported. First, GlcNAc importation and intracellular metabolic pathways were disrupted by the deletion of nagF , nagE , nagC , nagA and nagB genes. Second, the GlcNAc-6-phosphate N -acetyltransferase gene (gna1) was screened. A GlcNAc-producing strain was constructed by overexpressing a mutant gna1 from Caenorhabditis elegans. A further increase in GlcNAc production was achieved by disrupting poly(3-hydroxybutyrate) biosynthesis and the Entner–Doudoroff pathways. The maximum GlcNAc titers were 199.9 and 566.3 mg/L for fructose and glycerol, respectively. Finally, the best strain achieved a GlcNAc titer of 75.3 mg/L in autotrophic fermentation. This study demonstrated a conversion of CO 2 to GlcNAc, thereby providing a feasible approach for the biosynthesis of various bioactive chemicals from CO 2 under normal conditions.. [ABSTRACT FROM AUTHOR]

A facile solvothermal method was adopted to prepare unique hierarchical TiO 2 structures which are assembled from single-crystal tubes and inflated with oriented aligned nanoparticles. A F − mediated anisotropic assembling mechanism was proposed based on time dependent experiments and density function theory calculation. Hydrofluoric acid was found to play crucial roles on the nucleation, growth and assembling stages and hierarchical TiO 2 structures consisted of solid and hollow branches could be selectively prepared via simply altering the hydrofluoric acid dosages. The as-prepared hierarchical TiO 2 structures were employed as triple-functional photoanode material to boost the performances of CdS/CdSe sensitized solar cells. The hexagonal tubes with well-defined crystal facets exhibited high light-reflection rate for the incident light. Meanwhile, the inflated nanoparticles offered high accessible surface area of ∼71 m 2 g −1 , and the oriented aligned structures minimized the inter-particles defects to suppress the undesired charge recombination. Due to these structural qualities, the light harvesting efficiency and electron life time were substantially enhanced, which leads to a power conversion efficiency of 4.9%, representing a ∼40% improvement compared with nanoparticle based device (3.5%). [ABSTRACT FROM AUTHOR]

ZnO nanorods consisted of oriented aligned elongated-nanoparticles along the [0001] direction were readily prepared with tunable aspect ratios by a facile solvothermal method. An oriented-attachment growth mechanism was proposed based on time-dependent trails and first principle density function theory calculation. Control experiments indicated that the reaction medium played important roles to influence the oriented-attachment process and the aspect ratio could be tuned from ∼4.6 to ∼16.0 by simply altering the precursor dosages. The as-prepared ZnO nanorods were applied as photoanode materials in quantum-dot sensitized solar cells. The large pore size in the film structure and rough surface of the nanorod could enhance the quantum dots loading amounts and light scattering effect. In addition, the orderly aligned primary ENPs minimized the grain boundaries for suppressed recombination and provided a direct pathway for increased electron diffusion length. Meanwhile, the enhanced film hydrophilicity facilitated the electrolyte penetration and the regeneration of oxidized sensitizers. Therefore, a high power conversion efficiency of ∼4.83% was demonstrated, indicating substantial improvement compared with that of traditional nanoparticle based device (∼3.54%). [ABSTRACT FROM AUTHOR]

[Display omitted] • Heterotrophic and autotrophic myo -inositol production was achieved in C. necator. • Myo -inositol biosynthetic pathway was constructed by expression of Sc IPS and Ec IMP. • Central metabolic network modification enhanced the myo -inositol production. • The production level of myo -inositol (1054.8 mg/L) from CO 2 set up the record. Bioconversion of sustainable feedstocks to commodity chemicals is considered as an effective solution for transforming the fossil-based economy into a carbon–neutral model. Here, the CO 2 -fixing bacterium Cupriavidus necator H16 was exploited for myo -inositol production from renewable substrates. First, by introducing the glucose transportation system, the glucose consumption route was established. Second, two key enzymes involved in myo -inositol biosynthesis were screened and evaluated. A myo -inositol-producing strain was constructed via overexpression of myo -inositol-3-phosphate synthase from Saccharomyces cerevisiae and inositol monophosphatase from Escherichia coli. Finally, carbon flux redirection was achieved through disruption of Entner-Doudoroff pathway and poly(3-hydroxybutyrate) synthesis pathway, resulting in a final myo -inositol production of 520.2, 1076.3 and 1054.8 mg/L from glucose, glycerol and CO 2 , respectively. The myo -inositol production level from CO 2 achieved here set up the record. This study underlines the potential of C. necator to be utilized as microbial factory for upcycling the renewable feedstocks and CO 2 to high-value biochemicals. [ABSTRACT FROM AUTHOR]

The aerodynamic reduced order model (ROM) is an effective tool for predicting unsteady aerodynamics and aeroelastic responses with high accuracy and low computational costs. However, traditional aerodynamic ROMs with respect to different flow conditions are lack of robustness. How to enhance dramatically the generalization capability of aerodynamic ROMs should be further studied. This paper presents three parametric ROMs based on the least squares support vector regression algorithm (LS-SVR) and two incremental learning algorithms. LS-SVR is used to establish the relationship between aerodynamic inputs and outputs based on training data from high-fidelity flow simulations. And the Mach number is considered as an additional system input to account for varying flow conditions. The main contribution of incremental learning algorithms based on LS-SVR is that it does not need to reconstruct the ROM when adding sample data. For incremental learning algorithm with forgetting mechanism, training samples are added in the manner of a time-window to improve training efficiency. To illustrate the performance of these ROMs, the aerodynamic and aeroelastic responses of a NACA 0012 airfoil with two degrees of freedom are investigated. The simulation results show that both unsteady aerodynamic results and aeroelastic responses computed by using the three ROM-based models agree well with the results of the high-fidelity simulation. The three proposed ROMs have better generalization capacity and modeling efficiency. [ABSTRACT FROM AUTHOR]

Retinoblastoma binding protein 4 (RBBP4) is a nuclear protein with four WD-repeat sequences and thus belongs to a highly conserved subfamily of proteins with such domains. This retinoblastoma-binding protein plays an important role in nucleosome assembly and histone modification, which influences gene transcription and regulates cell cycle and proliferation. Artemia sinica (brine shrimp) undergoes an unusual diapause process under stress conditions of high salinity and low temperature. However, the role of RBBP4 in diapause termination of embryo development in A. sinica remains unknown. Here, the full-length cDNA of the As-rbbp4 gene was obtained from A. sinica and found to contain 1411 nucleotides, including a 1281 bp open reading frame (ORF), 63 bp 5′-untranslated region (UTR) and a 67-bp 3′-UTR, which encodes a 427 amino acid (48 kDa) protein. Bioinformatic analysis indicated As -RBBP4 to be mainly located in the nucleus, with a theoretical isoelectric point of 4.79. Protein sequence domain analysis showed that As -RBBP4 is a conserved protein, especially in the WD40 domain. No specificity in expression of this gene was observed in tissues or organs by in situ hybridization. Real-time quantitative PCR and Western blot analyses of As -RBBP4 gene and protein expression, respectively, showed notably high levels at 10 h and a subsequent downward trend. Obvious trends in upregulation of As -RBBP4 were observed under conditions of low temperature and high salinity stress. As- E2F1 and As- CyclinE also presented similar trends as that of As- RBBP4 in Western blots. Analysis of the RBBP4 expression in early embryonic development of A. sinica indicated that this protein plays an important role in diapause termination and cell cycle regulation. [ABSTRACT FROM AUTHOR]