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Objective This research was designed to investigate the function of miR-1275 in hypoxia/reoxygenation (H/R)-induced myocardial injury and its in-depth mechanism. Methods Firstly, the differential expression of miR-1275 in patients with heart failure and healthy control were analyzed based on Gene Expression Omnibus (GEO) database. Then H/R model was constructed in vitro with AC16 cells. The qRT-PCR assay was performed to analyze the expression of miR-1275 in H/R-treated cells. Afterwards, CCK-8 assay and flow cytometry assay were carried out to detect the cells viability and apoptosis. Bioinformatics prediction, western blotting and dual-luciferase reporter assays were set to check the target gene of miR-1275. Finally, we used an Elisa to test the effect of miR-1275/HK2 axis on inflammatory factors. Results We found that miR-1275 was highly expressed in patients with heart failure and H/R treated AC16 cells than that in control group, and inhibition of miR-1275 can alleviate induced-decrease of cell viability. Subsequently, we revealed that HK2 was a downstream target gene of miR-1275, which was lowly expressed in patients with heart failure. Furthermore, our data also suggested that inhibition of miR-1275 can significantly alleviate H/R-induced myocardial injury, which can also markedly decrease the concentration of pro-inflammatory factors TNF-α, IL-1 β and increase the concentration of anti-inflammatory factors IL-10 in H/R-treated AC16 cells, while knockdown of HK2 canceled the effect caused by miR-1275 deletion. Conclusions In summing, our results illustrated that miR-1275/HK2 axis act as a potential regulator to against H/R-induced AC16 cells injury through anti-inflammatory effect.

The “dolomite problem” is a key issue in research on carbonate diagenesis, and it is still a controversial scientific problem. The origin of the Neogene dolostones in the Xisha Islands has remained disputed until now. However, the geochemical characteristics of dolomite-hosted fluid inclusions can potentially provide a relatively direct record of the origin and evolution of their dolomitizing fluid. In this article, based on the samples selected from the well “Xike-1” (also known as “ZK-1” and “XK-1”) reef core of the Xisha Islands, the hydrogen isotopic compositions and gas and liquid compositions of the fluid inclusions hosted in calcite and dolomite were analyzed. Meanwhile, the isotopic compositions of carbon and oxygen in the calcite and dolomite minerals were also tested. The origin of the dolomitizing fluid was traced in detail, which provided important evidence for establishing the dolomitization model of the primary dolomites in the study area. The main gas compositions of the dolomite-hosted fluid inclusions are CO2, H2O, N2, and O2, which are similar to those of the atmosphere, indicating that the dolomites in this area experienced a partly oxygenated diagenetic environment. From high to low, the cation concentrations of the liquid component in the dolomite-hosted fluid inclusions are Mg2+, Ca2+, Na+, and K+, whereas their main anion compositions are SO42−, Cl−, and F−, which are characterized by high SO42− concentrations and low Cl/Br ratios. The δ13C values (PDB) of the dolomites range from 1.9‰ to 3.0‰, and their δ18O values (PDB) range from 2.1‰ to 4.7‰. The calculated Z values (which can be used to trace the salinity of diagenetic fluid) based on the δ13C and δ18O values of the dolomites range from 133.0 to 135.8, which are higher than that of modern seawater (approximately 120). These data indicate that the dolomitizing fluid of the primary dolomites in the Xisha Islands is the high-salinity concentrated seawater derived from a surface environment. In addition, the model of seepage-reflux dolomitization can better interpret the dolomitizing process of the primary dolomites in the Xisha Islands.

The present work aimed at evaluating the performance of a gas engine driven heat pump (GEHP) for cooling and hot water supply. A test prototype working with R134a was built, and the cooling performance with hot water supply were experimented in a range of evaporator water inlet temperature from 12 °C to 22 °C, ambient air temperature from 24.2 °C to 37 °C, and gas engine speeds from 1400 rpm to 2000 rpm. The results show that the effects of evaporator water inlet temperature and gas engine speed on the system performance are more significant than those of ambient air temperature. Average hot water outlet temperatures between 40.7 °C and 61.7 °C are obtained over the considered range of the external operating parameters and this met the temperature demand of domestic water for shaving, residential dish washing, and laundry. Moreover, the primary energy ratio (PER2) of GEHP system is between 1.14 and 1.45 with waste heat recovery.

The present work is aimed at exploring the performance characteristics of a gas engine heat pump (GEHP) system in the aspect of the heating and domestic hot water. A test prototype was established using R134a as working fluid. The performance characteristics of the gas engine and the GEHP system working were studied by experiments in heating mode. The results showed that the output efficiency of the gas engine increased when the gas engine speed is constant. The coefficient of performance (COP) and primary energy ratio (PER) of the GEHP system decreased with the growing of the gas engine speed, but increased with increasing condenser water inlet temperature and ambient air temperature. And the PER of the GEHP system was between 1.23 and 1.48 under experimental condition. In addition, the energy of heat recovery accounted for about 30%–45% of the total heating capacity of the GEHP system, and the temperature of the domestic hot water which was heated by the waste heat could reach 40 °C–60 °C, thus ordinary families' demands for domestic hot water could be satisfied.

To achieve cascade utilization of waste heat of gas engine, a parallel gas engine compression-absorption heat pump (GECAHP) combined a compression-type heat pump and an absorption-type heat pump was proposed and modeled. The compression-type heat pump is driven by the motive power from the gas engine and the absorption-type heat pump is activated by the waste heat of exhaust gas. Based on the simplified model, the heating performance of the GECAHP system and the energy-saving potential compared with conventional gas engine heat pump (GEHP) system are simulated. The results show that as the gas engine speed increases from 1500 rpm to 2500 rpm, the total heating capacity and primary energy consumption increase by 54.5% and 64.9%, respectively, while the primary energy ratio decreases by 5.5%. It has a smaller effect on the performance of GECAHP for exhaust gas outlet temperature compared with the water inlet temperature and ambient air temperature. In this work, the maximum primary energy ratio of GECAHP system is greater than 1.5 considering the energy consumption of the fans and solution pump. Compared with conventional GEHP system, GECAHP system can produce more than 6% of heating capacity and save around 5% of primary energy.

Background: Allogeneic chimeric antigen receptor T (CAR-T) cells receive activation signals from both T cell receptors (TCR) and CARs, which may possess stronger activity in anti-leukemia cells. However, the safety and efficacy of donor-derived CAR-T cells in treating relapsed patients with B-cell acute lymphoblastic leukemia (B-ALL) after allo-HSCT are not yet clear. Methods: Relapsed patients with CD19-positive B-ALL after allo-HSCT in this respective study received donor-derived CD19.CAR-T cells treatment. The safety and long-term outcomes that related to demographic, clinical, and disease characteristics were analyzed. Findings: 43 patients received CD19.CAR-T cell treatment. Complete remission was observed in 79.07% of the patients. Cytokine release syndrome (CRS) of any grade occurred in 38 of 43 patients (88.37%); 2 patients died. Patients with low disease burden (

Ag/Ti3AlC2 composites prepared by equal channel angular pressing (ECAP) exhibit preferential alignment of Ti3AlC2. Arc erosion behaviors of the Ag/Ti3AlC2 with the alignment of Ti3AlC2 particles parallel (ECAPed//) and perpendicular (ECAPed⊥) to contact surface were investigated. The ECAPed// sample shows superior arc erosion resistance to the ECAPed⊥ one according to the results on surface and cross section examinations, and mass, area and thickness losses. The mechanisms responsible for arc erosion behaviors are discussed in terms of thermodynamic calculations and lattice anisotropic considerations on the oxidation process of Ti3AlC2. The present work provides practical guidance in designing high-performance Ag/MAX electrical contacts.

The present work aims to explore a new energy supply way for users with chilled and hot water demand in summer. To achieve this goal, a water source gas engine-driven heat pump (WSGHP) system with R134a was developed. The WSGHP system used evaporator to product chilled water, at the same time, made use of condensing heat and engine waste heat to product domestic hot water. The impact of engine speed, evaporator/condenser water inlet temperature on the gas consumption, cooling capacity, heat recovery, and system energy efficiency had been researched in detail. Testing results indicated that the WSGHP system was able to perform stably under various conditions. The primary energy ratio without heat recovery (PER1) of system is from 0.61 to 0.85. However, when the condensing heat and engine waste heat are recovery, its primary energy ratio (PER2) is 2.09–2.34. The cooling capacity, condensing heat and engine waste heat account for 31.5%, 40.0%, and 28.5% of the total capacity of the system, respectively. Therefore, the new energy supply system has great significance to the development of energy-saving and environmental protection.

SiCp/2024Al composite foams were manufactured by powder metallurgical methods using foaming agent CaCO3 in order to enrich the foam fabrication process and promote its development and extensive application. The effects of CaCO3 and SiC volume fractions on the foaming behaviours were investigated by means of SEM and Magiscan-2A image analysis technique. The influence of SiC content on the compressive behaviour was analyzed using Gleeble 1500 thermal simulation testing machine. The experimental results show that with increasing the foaming agent, the porosity and pore dimension increase first and decrease later. With increasing the reinforcement content, the porosity and pore dimension decrease. The compressive curves reveal that the introduction of SiC particles can improve compressive yield strength and energy absorption capacity. Meanwhile, it is found that SiCp/2024Al composite foams are the brittle foam materials.

SiC p /Al-Ti foils were prepared by hot-pressing and hot rolling. The diffusion reaction between Ti and SiC p /Al was investigated and multi-layers of intermetallics formed during reaction annealing at 1 200°C. The microstructure and the composition in each intermetallic layer were characterized using scanning electron microscope (SEM) equipped with energy dispersive spectroscope (EDS). The products from the reaction between SiC and titanium aluminides were determined by X-ray diffractometer (XRD) and the thermodynamics of the reaction was investigated using differential thermal analysis (DTA). The results show that different reactive layers form in the sample and SiC particles disappear with the formation of intermetallic layers after annealing. Intermetallic multi-layers are determined to be Ti 3 Al, TiAl and TiAl 3 . SiC particles react with titanium aluminide during reaction annealing to form Ti 3 AlC, TiC, Ti 5 Si 3 and Ti 3 SiC 2 .

Calcitriol, the active form of vitamin D, exerts important immunoregulatory effects. After rat liver allografting, calcitriol suppresses acute rejection. The aim of this study was to investigate whether calcitriol regulates hepatocyte apoptosis, in parallel with its inhibition of acute rejection in rat liver allografts. Liver allografts were transplanted in a high responder strain combination (SD to Wistar rats) and calcitriol was administered to the recipients, while control recipients received no immunosuppressant. Graft specimens were harvested on postoperative days 1, 3, 5 and 7 for histological analysis and protein assay. Hepatocyte apoptosis was assessed by the TUNEL method. Levels of intragraft Bcl-2, Bcl-xL, Bax, TNF-alpha and IFN-gamma proteins were measured by Western blot analysis. Expression of Fas, Fas ligand and caspase-3 was determined by immunohistochemical analysis. Calcitriol markedly inhibited hepatocyte apoptosis. In the calcitriol-treated allografts, Bcl-2 and Bcl-xL levels increased while Bax and caspase-3 levels significantly decreased. The expression of Fas ligand was clearly reduced while Fas remained unchanged. TNF-alpha and IFN-gamma proteins were also significantly decreased in the presence of calcitriol. These results show that calcitriol acts as a promoter of the anti-apoptosis genes Bcl-2 and Bcl-xL and an inhibitor of the pro-apoptosis genes Bax and caspase-3. These effects may be related to its suppression of the Fas/Fas ligand pathway and its inhibition of cytotoxic T lymphocyte products.

Three kinds of A1-11%Si (mass fraction) alloy samples with different processes were produced to investigate the effect of microstructures on its superplasticity. Among them, the as-ECAP sample pressed 16 passes has ultrafine grains (300 nm) and the finest secondary particles. The ECAP-T6 sample, with ECAP 16 passes followed by T6 treatment, has fine secondary particles (3 μm) but the largest grains (8 μm). Contrarily, the T6-ECAP sample, with T6 treatment followed by ECAP 16 passes, has ultrafine grains and the large secondary particles (7 μm). The tensile testing results show that the as-ECAP sample exhibits superplasticity at high strain rate of 5.75 × 10−1s−1 due to its fine secondary particles and ultrafine grains. The ECAP-T6 sample, however, does not exhibit superplasticity at the same high strain rate of 5.75×10−1 s−1 because it has relatively large secondary particles and large grains. Remarkably, the T6-ECAP sample does not have superplasticity even at the lower strain rate of 1.15 × 10−1 s−1, attributing to its comparatively large secondary particles. When most secondary particles are larger than 7 μm, the high strain rate superplasticity could not be obtained even if this sample has ultrafine grains.

Two new selenidostannates [M(tepa)]2(μ2-Sn2Se6) (tepa = tetraethylenepentamine, M = Fe2+ 1 and Co2+ 2) were prepared by solvothermal reaction at 157 °C. Compounds 1 and 2 are isostructural. The M2+ ion has a distorted octahedral geometry comprised of five N atoms from tepa ligands and one terminal Se atom of the Sn 2 Se 6 4 - anion. As a bridging ligand, Sn 2 Se 6 4 - anion connects two transition metal complex cations by trans terminal Se atoms to form neutral centrosymmetric [M(tepa)]2(μ2-Sn2Se6) moieties. Their thermal and optical properties were studied.

Al-11%Si (mass fraction) alloy was transformed into a ductile material by equal-channel angular pressing (ECAP) with a rotary die. Two mechanisms at impact test, slip deformation by dislocation motion and grain boundary sliding, were discussed. The ultrafine grains with modified grain boundaries and the high content of fine particles (

A complete set of match calculation method for optimum sizing of a PV/wind hybrid system is presented. In this method, more accurate mathematic models for characterizing components as well as models for estimating the available natural resources are adopted; in order to find the optimum configuration which meets the energy demand at the minimum cost, firstly by fixing the capacity of wind generator, the optimum PV/wind/battery combination corresponding to this capacity of wind generator is determined; then by changing the capacity of the wind generator, the optimized PV/wind/battery combinations corresponding to different capacities of wind generators are determined similarly; finally by comparing their initial equipment costs, the optimum configuration which meets the energy demand with the minimum cost can be uniquely determined. According to this match calculation method, a calculation example is given by using the hourly meteorological data of the Waglan island of Hong Kong.