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Objective. Ischemic heart disease (IHD) has always been the focus of attention of many researchers in cardiovascular disease, and its pathogenesis is also very complicated. Ferroptosis may be involved in the occurrence and development of IHD. Methods. First, primary cardiomyocytes were treated with H2O2 to simulate the IHD in vitro model. After pretreatment with different concentrations of ferrostatin-1, cell survival rate was detected by MTT method, cell apoptosis was detected by TUNEL staining and flow cytometry, and the expression of oxidative stress, ferroptosis, and related molecules of Nrf2/ARE pathway was detected by Western blotting (WB) and quantitative real-time polymerase chain reaction (qRT-PCR). Results. The mortality of primary cardiomyocytes in the H2O2 group was obviously increased. Ferrostatin-1 treatment can effectively inhibit cell death, improve antioxidant enzyme activity, inhibit the expression of ferroptosis-related molecules, and activate Nrf2/ARE pathway expression. Conclusion. Ferroptosis-specific inhibitor ferrostatin-1 relieves H2O2-induced redox imbalance in primary cardiomyocytes through the Nrf2/ARE pathway, inhibits ferroptosis, and thereby slows cardiomyocyte death.

We report that quasi-inorganic inks and interface engineering trigger a large enhancement of thermoelectric performance in 3D-printed Bi2Te3-based materials.

Objective This study collected randomized controlled trials (RCTs) published in the social sciences in China and assessed their risk of bias and reporting quality. Study Design and Setting Three databases were systematically searched for publications from January 2000 to June 2020 for RCTs in the social sciences published by Chinese researchers. The risk of bias was assessed using the Cochrane Collaboration Risk of Bias Tool (CCRBT), and reporting quality was assessed using the Consolidated Standards of Reporting Trials for Social and Psychological Interventions (CONSORT-SPI). Results A total of 316 RCTs were identified, including 204 articles in English and 112 articles in Chinese. The most frequently researched interventions focused on education (33.9%), and the most frequently studied population were students (32.9%). Eighty-seven percent of RCTs had intermediate reporting quality. Twenty-four of the 43 CONSORT-SPI sub-items had a compliance rate of less than 50%. Most RCTs had an unclear risk of bias for blinding outcome assessors (84.5%), blinding participants and personnel (82.9%), allocation concealment (73.1%), and random sequence generation (68.0%). A low proportion of CONSORT-SPI items were reported and, high proportion of the papers had unclear risk of bias. Conclusion The quality and reporting of RCTs in the social sciences needs improvement in China, especially for reporting methods and results. Most studies had an unclear risk of bias as they lacked important methodological information.

Recently discovered magnetic van der Waals (vdW) materials provide an ideal platform to explore low-dimensional magnetism and spin transport. Its vdW interaction nature opens up unprecedented opportunities to build vertically stacked heterostructures with novel properties and functionalities. By engineering the planar structure as an alternative degree of freedom, herein we demonstrate an antisymmetric magnetoresistance (MR) in a vdW Fe3GeTe2 flake with a step terrace that breaks the planar symmetry. This antisymmetric MR originates from a sign change of the anomalous Hall effect and the continuity of the current transport near the boundary of magnetic domains at the step edge. A repeatable domain wall due to the unsynchronized magnetization switching is responsible for this sign change. Such interpretation is supported by the observation of field-dependent domain switching, and the step thickness, temperature, and magnetic field orientation dependent MR. This work opens up new opportunities to encode magnetic information by controlling the planar domain structures in vdW magnets.

In order to solve the problem of agglomeration of graphene in preparation of composites, GN-CeO2 powders with even dispersion were obtained by a hydrothermal reduction method, which involved modify...

Objectives To assess the reporting and methodological quality of COVID-19 systematic reviews, and to analyze trends and gaps in the quality, clinical topics, author countries, and populations of the reviews using an evidence mapping approach. Study Design and Setting A structured search for systematic reviews concerning COVID-19 was performed using PubMed, Embase, Cochrane Library, Campbell Library, Web of Science, CBM, WanFang Data, CNKI, and CQVIP from inception until June 2020. The quality of each review was assessed using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) checklist and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. Results In total, 243 systematic reviews met the inclusion criteria, over 50% of which (128, 52.7%) were from 14 developing countries, with China contributing the most reviews (76, 31.3%). In terms of methodological quality of the studies, 30 (12.3%) were of moderate quality, 63 (25.9%) were of low quality, and 150 (61.7%) were of critically low quality. In terms of reporting quality, the median (interquartile range) PRISMA score was 14 (10–18). Regarding the topics of the reviews, 24 (9.9%) focused on the prevalence of COVID-19, 69 (28.4%) focused on the clinical manifestations, 30 (12.3%) focused on etiology, 43 (17.7%) focused on diagnosis, 65 (26.7%) focused on treatment, 104 (42.8%) focused on prognosis, and 25 (10.3%) focused on prevention. These studies mainly focused on general patients with COVID-19 (161, 66.3%), followed by children (22, 9.1%) and pregnant patients (18, 7.4%). Conclusion This study systematically evaluated the methodological and reporting quality of systematic reviews of COVID-19, summarizing and analyzing trends in their clinical topics, author countries, and study populations.

When preparing nano silicon powder by high-energy ball milling, the grain size of the obtained nano silicon powder varies with different technical parameters set in the ball milling process. In ord...

The manipulation of two-dimensional (2D) ferromagnetic materials by spin current is emerging as the central theme of 2D spintronics research. A paradigm of spintronic devices, the spin Hall magneto...

In this work, Mn/Eu co-doped Zn–Mg-Ge-O composite system was prepared by high temperature solid phase method. After 375 nm external excitation, Zn–Mg-Ge-O system emitted four visual colors of red, orange, yellow and green afterglow. Phase analysis proved that these four visual colors were derived from both red long afterglow emitted from Mn/Eu co-doped MgGeO3 (expressed as MgGeO3:Mn,Eu) and green afterglow from Mn/Eu co-doped Zn2GeO4 (Zn2GeO4:Mn,Eu). The change of Zn content could modulate the intensity ratio of red and green afterglow, ultimately resulted in different visual colors. The luminescence mechanism of MgGeO3:Mn,Eu and Zn2GeO4:Mn,Eu was quantitatively studied by DFT simulation. Although the emission centers of MgGeO3:Mn,Eu and Zn2GeO4:Mn,Eu were same Mn ion, electron-hole separation and electronic transition path of emission were different. The electron-hole separation of MgGeO3:Mn, Eu occurred at the 6A1(S) level of Mn ion, and that of Zn2GeO4:Mn,Eu occurred in the valence band (VB). Downward transition path of electrons in MgGeO3:Mn,Eu was 4T2(D)→6A1(S), while that in Zn2GeO4:Mn,Eu was 4T2(D)→VB. In addition, Eu ion in no matter MgGeO3 or Zn2GeO4 worked as trap center, however the trap depth was different.

Recently developed deep learning-based image inpainting methods have suggested their potential applications in filling large missing regions displaying plausible content. Nevertheless, most existing studies either merely considered the external information of the missing regions or relied on the region context to yield semantically coherent patches while overlooking the semantic relevance and feature continuity exhibited by missing regions; these demerits are likely to cause a discontinuous contextual structure and blurry texture details. In this work, a novel inside-outside attention layer (IOA) was proposed, capable of exploiting unmasked image features as references as well as learning the affinity between hole features to predict more consistent semantic information. The adversarial loss attributed exclusively on the natural image level cannot adequately generate a sharp texture detail. To address this problem, a texture component discriminator was introduced via wavelet decomposition to enhance the specific performance. Several experiments were performed on the CelebA and Places2 datasets. As revealed from the results, in contrast to the existing research, the proposed method is capable of restoring images with complex structures and significantly enhancing plausible structure and visual quality.

Objective. Studies have shown that long noncoding RNAs (lncRNAs) play crucial roles in multiple tumor types and regulate various biological processes. The present study tried to study lncRNA TFAP2A-AS1 in HBV infection hepatocellular carcinoma. Methods. The level of TFAP2A-AS1 and miR-933 in HCC cell and samples were detected by qRT-PCR assay. Luciferase reporter gene assay was carried out to study the mechanism of TFAP2A-AS1 and miR-933. Cell proliferation was measured by CCK-8 assay. HBV DNA replication was detected by RT-qPCR. Results. We firstly demonstrated that TFAP2A-AS1 was downregulated in HCC cell lines and HBV-infected HCC samples compared with nontumor tissues. However, miR-933 was upregulated in HCC cell lines and HBV-infected HCC samples compared with nontumor tissues, and miR-933 was negatively associated with the expression of TFAP2A-AS1 in HBV-correlated HCC samples. TFAP2A-AS1 and HDAC11 expression was decreased and miR-933 was upregulated in the HBV-infected cell HepG2.2.15. TFAP2A-AS1 acted as a sponge for miR-933 and HDAC11 was one direct target gene for miR-933. Overexpression of TFAP2A-AS1 suppressed cell growth, HBV DNA replication, HbeAg, and HbsAg expression, while knockdown of TFAP2A-AS1 enhanced cell proliferation, HBV DNA replication, HbeAg, and HbsAg expression in HepG2.2.15 cell. In addition, ectopic expression of miR-933 promoted cell growth, HBV DNA replication, HbeAg, and HbsAg expression in HepG2.2.15 cell. TFAP2A-AS1 suppressed HBV replication and infection through regulating HDAC11. Conclusion. These data demonstrated that TFAP2A-AS1 acted crucial roles in the modulation of HbeAg and HbsAg expression and HBV replication and may be one potential target for HBV infection treatment.

Long non-coding RNA SOX2 overlapping transcript (SOX2OT) is closely related to heart failure and myocardial damage. We attempted to investigate its role in endotoxin lipopolysaccharide (LPS) injury in cardiomyocytes.Cell viability, apoptosis rate, and levels of pro-inflammatory cytokines and apoptosis- and oxidative stress-related proteins were measured by MTS assay kit, flow cytometry, western blotting, and commercial kits. Physical interactions were confirmed by dual-luciferase report assay and RNA immunoprecipitation assay.Silencing SOX2OT and reinforcing miRNA (miR)-215-5p protected human AC16 cardiomyocytes from LPS-induced oxidative and inflammatory injuries by inhibiting intercellular adhesion molecule 1 (ICAM1). SOX2OT directly interacted with miR-215-5p, and miR-215-5p could target ICAM1.Inhibiting SOX2OT/miR-215-5p/ICAM1 axis might be a possible approach to treat myocardial damage.Lipopolysaccharide (LPS) is an endotoxin from some bacteria including Escherichia coli, and it can cause inflammation in different tissues/cells including myocardia/cardiomyocytes, resulting in diseases such as myocarditis, cardiomyopathy, and cardiac hypertrophy. The underlying mechanism was not completely clarified, but known to include the dysregulation of non-coding RNAs. Herein, we demonstrated the biological role of long non-coding RNA SOX2 overlapping transcript (SOX2OT) in LPS-infected cardiomyocytes. Eventually, we found that inhibiting the expression of SOX2OT could mitigate LPS-induced a series of injuries in human cardiomyocytes, and SOX2OT interacts with a microRNA named as miR-215-5p. Besides, restoring miR-215-5p elicited similar effects to SOX2OT knockdown. Collectively, we concluded that SOX2OT binding to miR-215-5p might protect cardiomyocytes from LPS infection through regulating an important protein named ICAM1. This study suggested SOX2OT/miR-215-5p might be novel potential treatment targets in bacterial infection-related myocardial damages.

Facile electro-thermal igniters based on freestanding carbon nanotubes (CNTs) films are investigated for exploring the use of igniting energetic materials. Increases in electro-thermal temperature, dynamic pictures of ignition process, and temporal changes of voltage, current and resistance as well as the ignition ability of freestanding CNTs film–based igniters with different film thickness are compared with their counterparts with paper-like substrate. The results demonstrated that freestanding CNTs film–based igniters had faster rise in electro-thermal temperature and better ignition ability than their counterparts. The ignition delay of loaded energetic materials employing freestanding CNTs film based–igniters was only 40%–67% of their counterparts depending on the film thickness. Freestanding CNTs film–based igniters with larger thicknesses were more suitable for the rapid ignition of energetic materials. The shortest ignition delay for igniters of 8 × 8 mm bridge area under 20 V was less than 80 ms. The initial temperature rise rate of igniters was crucial for deciding the ignition delays of loaded energetic materials. The presence of substrates in CNTs film–based igniters impeded their temperature rise rate and thus increased the ignition delay of loaded energetic materials. Moreover, due to the property of negative resistance-temperature coefficient, freestanding CNTs film–based igniters are favourable for the realization of low voltage ignition of energetic materials.

Perovskite/silicon tandem solar cells are promising avenues for achieving high-performance photovoltaics with low costs. However, the highest certified efficiency of perovskite/silicon tandem devices based on economically matured silicon heterojunction technology (SHJ) with fully textured wafer is only 25.2% due to incompatibility between the limitation of fabrication technology which is not compatible with the production-line silicon wafer. Here, a molecular-level nanotechnology is developed by designing NiO

In this work, we propose a novel technique based on wavelength dispersive in situ fluorescence spectroscopy (WDIFS) for diagnosing the wavelength-dependent directional charge transportation and Rayleigh scattering enhanced in-band quantum yield. For the first time, it is clearly demonstrated that the formation of the 2D electron gas in CuO/ZnO and upward Schottky barriers in ZnO/Ag facilitate the photocatalytic performance in the ultraviolet spectral range, and that utilization of the visible spectrum relies on the band alignment between the energy level of the dopants and the Fermi level of Ag. Moreover, it is shown that the wavelength-dependent in-band quantum yield can be controlled through particle size photon scattering, in which the strong Rayleigh scattering based photon harvesting brings about a significant increase in the photocatalytic performance in the ultraviolet spectrum. Eventually, it is forecast that systematic use of the proposed technique for a systematic diagnosis should help towards the production of efficient ZnO-based photocatalysts.

A highly efficient Rhodamine B (RhB) adsorbent based on a gel-like ZnO/Zr-metal-organic framework (ZnO/Zr-MOF) composite was prepared by reacting ZnO nanoparticles with glacial-acetic-acid-modulated Zr-MOF(bpy) via a sample solvothermal method. Introduction of ZnO greatly improved the texture properties of the parent Zr-MOF(bpy), and the resulting material exhibited an agglomerate morphology consisting of numerous quadrate nanoparticles, which is quite different from the cubo-polyhedron morphology of Zr-MOF(bpy). In this way, this composite showed a considerable RhB absorption capacity from aqueous solution in a wide pH range. The adsorption kinetics, isotherms and thermodynamics of the RhB adsorption by ZnO/Zr-MOF(bpy) were discussed and confirmed that this adsorption process satisfied pseudo-second-order kinetics and the Langmuir model, and was a spontaneous exothermic process. Moreover, the excellent adsorption performance is likely related to the synergism of hydrogen bonding, electrostatic interactions and π–π interactions between the ZnO/Zr-MOF(bpy) nanocomposite and RhB. The excellent texture properties of ZnO/Zr-MOF(bpy) promote the adsorption and diffusion of RhB on it, which is also crucial during the adsorption process.

Recently, Metal-organic framework (MOF) has attracted general attention as self-sacrificial template to produce metal oxide semiconductor (MOS) for gas sensing. In this work, we fabricated a porous cubic microstructure of Co 3O4 through the facile pyrolysis of ZIF-67. The obtained Co3O4 sustained a similar cubic morphology with ZIF-67 template, but much improved pore structure was achieved. Moreover, we attempted to modify the Co 3O4 with Au nanoparticles . Through a facile post-synthesis adsorption & pyrolysis, the Au nanoparticles with an average size of 15–20 nm were evenly dispersed on the surface of Co 3O4. Then the obtained samples were investigated for acetone gas-sensing. Results showed that both Co3O4 and its Au doped structure could be used for acetone detection, while due to the existence of metal-semiconductor heterojunction and the catalysis and spillover functions of Au nanoparticles, the prepared Au/Co 3O4 composite showed much improved acetone response and much shortened response-recovery time than that of the bare Co3O4 structure.

In numerous applications of optoelectronic devices , MoS 2 is an appealing candidate because of the presence of a finite band gap. However, small ratio of electrical to thermal conductivity limits the developing in thermoelectric applications of MoS 2. Here, by using first-principles calculation, we investigated the thermoelectric performance of p-type monolayer MoS2 and the influence of strain on its thermal as well as thermoelectric properties. The thermoelectric conductivity can be reduced by tensile strain , while the Seebeck coefficient decreases at the same time, as a result of this the thermoelectric performance deteriorates. The underlying mechanism is also discussed in this paper.

By combining hydrogen bubbles dynamics template with electrodeposition, we successfully synthesized bulk open porous microstructure tin foam in several 10 sec. With the control of salt concentration and current density, we realized the well-controlled tuning of pore sizes and inter-pore distances, then eventually tuned the morphology and density of the as-synthesized tin foams. We have also investigated the structure and chemical composition of the as-synthesized tin foams by the scanning electron microscopy, X-ray diffraction and energy dispersive spectrometer. A formation mechanism of bulk tin foams was also proposed in this paper. Our studies imply that the parameters of current density, main salt concentration, and the surfactant play critical roles on the successful synthesis of desired bulk tin foams.

Two europium(III)-based metal–organic frameworks (MOFs) (Eu-BDC and Eu-BTC) have been synthesized by a solvothermal method with high sensitivity. It was found that the sensitivity of both Eu-BDC (0.065 vol%), which consists of flower-like microcrystals constructed by abundant nanoparticles, and Eu-BTC (0.06 vol%), which comprises nanolayer bunches, is below the occupational exposure limit of acetone (0.075 vol%) stipulated by the American Conference of Governmental Industrial Hygienists. In addition, Eu-BDC and Eu-BTC have good chemical stability and are promising for detection of acetone content in the environment. The fluorescence-quenching mechanism for Eu-BDC and Eu-BTC may be the fluorescence inner filter effect. Furthermore, the morphology of Eu-MOFs, that is, the specific surface area and pore size distribution, may be one of the factors affecting the fluorescence intensity and sensitivity of Eu-MOFs to acetone.

At present, direct generation of an ultrafast laser with a pulse width shorter than 10 ps in the visible spectral region has been very rarely demonstrated. In this work, we focus on this issue by operating an InGaN blue-diode-pumped Kerr-lens mode-locked Pr:LiYF4 laser. Using an undoped CaGdAlO4 crystal as an additional Kerr medium in the resonator for providing enhanced third-order nonlinearity, a stable mode-locked Pr:LiYF4 laser with red emission at 639 nm is achieved with the shortest pulse duration of 2.6 ps at a repetition rate of 49.7 MHz. The maximum average output power, single pulse energy, and peak power reach 68.4 mW, 1.38 nJ, and 530 W, respectively. To the best of our knowledge, this is the shortest pulse width that has ever been achieved in this specific emission line of Pr3+ ions.