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In this study, a sustainable water resources management (WRM) model with scenario-based mixed fuzzy-stochastic method with Green Z-score criterion method (SFGZ) is developed for coordinatin...

To elucidate whether miRNA-27a-3p can promote osteogenic differentiation of hMSCs by targeting ATF3, thus alleviating osteoporosis symptoms.The serum levels of miRNA-27a-3p in osteoporosis patients (n=20) and normal controls (n=20) were detected by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). Human bone marrow mesenchymal stem cells (hMSCs) were subjected to osteogenic differentiation for 1, 3 and 7 days. Subsequently, mRNA levels of miRNA-27a-3p, ALP, and Bglap in hMSCs were determined by qRT-PCR. The regulatory effects of miRNA-27a-3p levels and the mRNA levels of ALP, Bglap, and Runx2 were detected. After the overexpression or knockdown of miRNA-27a-3p, we evaluated the changes in the osteogenic differentiation by alizarin red staining and ALP staining. Through Dual-Luciferase Reporter Gene Assay, we verified the binding relationship between miRNA-27a-3p and ATF3. Rescue experiments were finally conducted to prove whether miRNA-27a-3p regulated the osteogenic differentiation by targeting ATF3.The serum level of miRNA-27a-3p remained lower in osteoporosis patients relative to controls. With the prolongation of osteogenic differentiation, the mRNA levels of miRNA-27a-3p, ALP, and Bglap gradually increased. The overexpression of miRNA-27a-3p upregulated mRNA and the protein levels of osteogenesis-related genes, increased ALP activity, and enhanced mineralization capacity. The knockdown of miRNA-27a-3p obtained the opposite trends. MiRNA-27a-3p could target ATF3, and the overexpression of ATF3 reversed the promotive effects of miRNA-27a-3p on osteogenic differentiation.MiRNA-27a-3p promotes the differentiation of hMSCs into osteoblasts by targeting ATF3, thus alleviating osteoporosis symptoms.

The thermal conductivity of a representative endothermic hydrocarbon aviation kerosene fuel RP-3 was accurately measured using the classical transient hot-wire method at sub- and supercritical pressures. The measured data cover a temperature range of 285 K to 513 K and a pressure range of 0.1 MPa to 5 MPa. The expanded uncertainty of the experiment was less than 3.0 % based on an uncertainty analysis. Furthermore, the measured data were correlated using a polynomial equation to analyze the deviations; 97.6 % of the measured data were within a 2 % error band. The average absolute deviation (AAD) and maximum absolute deviation (MAD) of the fitted thermal-conductivity data were 0.209 % and 2.31 % for all values, respectively.

Thermodynamic and kinetic analysis was performed in order to study the interfacial reaction mechanism of cubic boron nitride (CBN) abrasive grains and Ti activated Ag–Cu filler alloy during high temperature brazing. Meanwhile, microstructure of the interfacial layer was experimentally detected using scanning electron microscope (SEM), energy dispersion spectrometer (EDS) and X-ray diffraction (XRD) in the present paper. The results indicate that according to the thermodynamic theory, the interfacial reaction has been proved feasible, and during brazing the special active element Ti concentrated to and reacted with the CBN abrasive to form TiB2 and TiN, which joined hard the abrasive grain and steel substrate. Furthermore, the diffusion activation energy of the growing process in the interfacial reaction layer has discovered that the layer growth largely depends on the new formed TiN under conditions of 1153–1193 K and 5–30 min.

This paper summarizes our studies on transport and biodegradation of azo dyes in aerobic biofilms. Three lab-scale rotating drum biofilm reactors (RDBRs) were used to culture the biofilms. synthetic, municipal-type wastewater, spiked with several azo dyes, was continuously fed into the RDBRs. The study has revealed that Acid Orange 7 (AO7) and Acid Orange 8 (AO8) can be degraded aerobically in an efficient and effective manner under properly controlled operating conditions. The other dyes tested, however, are essentially non-degradable in an aerobic reactor. Microelectrodes and a microslicing technique have been used to elucidate changes in the structure of biofilms with depth and to determine the influence of these changes on mass transport and transformation processes. The results show that biofilms are non-homogeneous and highly stratified. Accordingly, biofilm is usually characterized by aerobic and anaerobic zones, with the anaerobic part used to break the azo bond and the aerobic surface layer to achieve the mineralization of anaerobically recalcitrant intermediates. Results concerning the inhibition effect of azo dyes on biofilm COD removal and respiration rate are also presented in this paper.

Direct measurement of unsteady-state variation of oxygen concentrations inside deactivated biofilm at intervals of 100 μm was conducted with oxygen microelectrodes. The diffusivity of each layer was estimated using an explicit finite-difference method. The results show that the distribution of the biofilm effective oxygen diffusivity varies from 25% Dw at the substratum of the biofilm to 90% Dw at the surface of the biofilm. This information provides experimental evidence necessary for biofilm modelling that could not be approached in the past, and will create a new dimension for evaluation of biofilm processes.

Competitions in biofilms for substrate and space have been studied by using a microelectrode technique and a microslicing technique. Three different kinds of biofilms, cultured by laboratory-scale rotating drum biofilm reactors (RDBR) with synthetic wastewater, have been used as test materials. Oxygen, ammonium-nitrogen, nitrate-nitrogen, and pH concentration profiles in the biofilms were measured using microelectrodes. Experimental results showed that: 1) an increase of organic loading rate would result in a decrease of DO concentration in the biofilm. However, after the organic loading rate exceeded a certain value, the oxygen profiles within the biofilm did not change any more; 2) Heterotrophs competed for oxygen with nitrifiers, which resulted in the inhibition of nitrification because of the shortage of oxygen. Glucose itself, however, did not inhibit the nitrification processes; and 3) The competition for substrate in biofilms resulted in a stratified biofilm structure. Experiments showed that competition in biofilms resulted in non-uniform spatial distributions of bacterial populations and metabolically active bacteria. The spatial distributions of biotic and abiotic components in turn affected the substrate transfer and substrate competition within the biofilm. Traditional biofilm modelling will fail in many cases if they are based on substrate removal kinetics and uniform distributions of biofilm properties.

Objective: Chromosome segregation during mitosis requires a physically large proteinaceous structure called the kinetochore to generate attachments between chromosomal DNA and spindle microtubules. It is essential for kinetochore components to be carefully regulated to guarantee successful cell division. Depletion, mutation or dysregulation of kinetochore proteins results in mitotic arrest and/or cell death. HEC1 (high expression in cancer) has been reported to be a kinetochore protein, depletion of which, by RNA interference, results in catastrophic mitotic exit. Materials and methods and results: To investigate how HEC1 protein is controlled post‐translation, we analysed the role of anaphase‐promoting complex/cyclosome (APC/C)‐Cdh1 in degradation of HEC1 protein. In this study, we show that HEC1 is an unstable protein and can be targeted by endogenous ubiquitin‐proteasome system in HEK293T cells. Results of RNA interference and in vivo ubiquitination assay indicated that HEC1 could be ubiquitinated and degraded by APC/C‐hCdh1 E3 ligase. The evolutionally conserved D‐box at the C‐terminus functioned as the degron of HEC1, destruction of which resulted in resistance to degradation mediated by APC/C‐Cdh1. Overexpression of non‐degradable HEC1 (D‐box destroyed) induced accumulation of cyclin B protein in vivo and triggered mitotic arrest. Conclusion: APC/C‐Cdh1 controls stability of HEC1, ensuring normal cell cycle progression.

In the present paper, a detailed analysis is given for the study of antihydrogen formation inP +Ps collisions in the presence of a purely monochromatic, linearly polarized laser field. The dressing effects are considered by the treatment of the dipole approximation and the perturbation approach up to first order. The angular distributions have been calculated for a few typical cases. It is shown that laser fields can produce significant modifications on the angular distributions.