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AbstractObjective: Treatment with c-kit-positive cardiac cells (CPCs) has been shown to improve the prognosis of ischemic heart disease. MicroRNAs (miRNAs) confer protection by enhancing the cardiac repair process, but their specific functional mechanisms remain unclear. This study aimed to screen for differentially expressed miRNAs in CPCs under hypoxia and explore their effects on the function of CPCs.Methods: We harvested CPCs from C57 adult mice and later performed a high-throughput miRNA sequencing for differential expression profiling analysis. Subsequently, we intervened with the differentially expressed gene miR-210-3p in CPCs and detected changes in the secretion of angiogenesis-related factors through a protein-chip analysis. Finally, we applied CPC supernatants of different groups as conditioned medium to treat mouse cardiac microvascular endothelial cells (CMECs) and further investigated the functional effects of miR-210-3p on c-kit+CPCs under ischemia and hypoxia conditions.Results: The miR-210-3p was highly increased in hypoxia-treated CPCs. Protein-chip detection revealed that CPCs expressed cytokines such as FGF basic, angiogenin, and vascular endothelial growth factor (VEGF) and that hypoxia enhanced their release. Silencing miR-210-3p resulted in a reduction in the release of these angiogenesis-related factors. In addition, the conditioned medium of hypoxia-treated CPCs promoted the proliferation, migration, and tube-forming capabilities of CMECs. In contrast, the conditioned media of CPCs with silenced miR-210-3p after hypoxia decreased the proliferation, migration, and tube-forming ability of CMEC.Conclusions: The CPCs exert proangiogenic effects via paracrine pathways mediated by miR-210-3p. Upregulation of miR-210-3p in hypoxia-treated CPCs may enhance their paracrine function by regulating the secretion of angiogenic factors, thereby promoting angiogenesis in ischemic heart disease.

Abstract Hypertension (HTN) is getting more prevalent in China, but the HTN's status in Guangxi remains unclear. Our study started from 2013 to 2015 and was dedicated to better acknowledging the status of HTN in Guangxi. The study enrolled 17,100 residents aged ≥ 15 years across Guangxi, from 2013 to 2015, using a stratified multistage random sampling method. Parameters including blood pressure (BP), height, and weight were measured by validated devices. HTN was defined as the average systolic BP (SBP) ≥ 140 mm Hg and/or average diastolic BP (DBP) ≥ 90 mm Hg, or any usage of antihypertensive medications within two weeks. The awareness, treatment, and control were defined as a self-reported history of HTN, a self-reported current usage of antihypertensive medications, and a BP lower than 140/90 mm Hg, respectively. The age and sex-standardized prevalence, awareness, treatment, control rates of HTN for the population aged ≥ 15 years in Guangxi were 15.80%, 16.48%, 11.99%, 3.62%, respectively. Prevalence and control rates were the same for men and women (P > 0.05), while women’s awareness and treatment rates were higher than those of men (P

Abstract Calcaneal quantitative ultrasonography (QUS) is a useful prescreening tool for osteoporosis, while the dual-energy X-ray absorptiometry (DXA) is the mainstream in clinical practice. We evaluated the correlation between QUS and DXA in a Taiwanese population. A total of 772 patients were enrolled and demographic data were recorded with the QUS and DXA T-score over the hip and spine. The correlation coefficient of QUS with the DXA-hip was 0.171. For DXA-spine, it was 0.135 overall, 0.237 in females, and 0.255 in males. The logistic regression model using DXA-spine as a dependent variable was established, and the classification table showed 66.2% accuracy. A receiver operating characteristic (ROC) analyses with Youden’s Index revealed the optimal cut-off point of QUS for predicting osteoporosis to be 2.72. This study showed a meaningful correlation between QUS and DXA in a Taiwanese population. Thus, it is important to pre-screen for osteoporosis with calcaneus QUS.

The malformation of sheet metal tapping screw threads in the screw threading process increases the cost of screw threading dies and their maintenance. Die factories do not reveal their screw threading die design techniques, so production and maintenance processes are established by trial-and-error or worker experience and passing down such techniques and documenting quality control is difficult. In this study, screw thread forming design and process analysis were carried out by combining computer-aided design software with computer-aided metal forming analysis software. Simulation results were verified in an actual forming process. The sheet metal tapping screw forging size error was less than 0.90%, except at a sharp angle, which was associated with an error of 3.075%, thereby demonstrating the accuracy of the simulated forming process. The numerical analysis process can be utilized to shorten forming development time; to reduce the number of die tests, and to improve product quality and die service life, reducing the cost of development and promoting the overall competitiveness of the company.

Surface oxidation frequently occurs in non-oxide antimony chalcogenides, which is a double-edged sword for their (opto)electronic properties and applications. Here we report that the photoelectronic performance of Sb2Se3 nanorods (NRs) can be improved through an appropriate degree of surface oxidation. During the synthesis, the volume ratio of oleic acid (OA)/oleylamine (OLA) was varied to control the oxidation degrees of the Sb2Se3 NRs, which span 1.20–51.49% with increasing OA ratio as revealed by X-ray photoelectron spectroscopy (XPS) analysis. A medium level of surface oxidation, typically 20–30% found here, is beneficial to the enhancement of the photocurrent, on/off ratios and photostability of the Sb2Se3 NRs when evaluated in a sandwich-type ITO/Sb2Se3/ITO photoconductor device. Surface hydroxylation, which is boosted by the presence of Sb–oleate and trace H2O remaining in the reaction system, is suggested to facilitate the formation of Sb–OH bonds and the OA-volume dependent oxidation at the surface of Sb2Se3. [ABSTRACT FROM AUTHOR]

Composition engineering is an active topic of research for optical and electronic (nano)crystals and functional materials. We here demonstrate the control over the ratios and distributions of selenium and sulfur in ternary Sb2(Se,S)3 alloy nanorods (NRs), which were synthesized from a molecular chalcogen precursor, selenium disulfide (SeS2). By increasing the anion/cation precursor ratios (SeS2/SbCl3) from 0.5 : 1 to 1 : 1 and 1.5 : 1, an increase in both the Se fractions and the lengths × diameters of NRs is achieved with the Se and S distributions in Sb2(Se,S)3 varying from homogeneity to inhomogeneity. Within the inhomogeneous NRs obtained at high SeS2/SbCl3 ratios containing excessive chalcogen (Se + S), S decreases but Se increases from the center to the periphery as revealed by EDS elemental analyses performed on individual NRs. In particular, the 1D growth anisotropy of NRs allows for a large chalcogen concentration gradient along the axial direction of the resulting NRs from their middle to the two ends. Such non-uniform Se and S distributions can be rationally interpreted by analyzing the growth kinetics and processes of Sb2(Se,S)3 NRs and would give rise to uncommon (opto)electronic properties towards future nanowire-based devices. [ABSTRACT FROM AUTHOR]

Antimony selenide (Sb2Se3) is a low-toxic, element-abundant, narrow bandgap (Eg = ∼1.1–1.3 eV) semiconductor that shows potential for UV-Visible-Near-infrared optoelectronic applications. This paper reports the use of potassium selenocyanate (KSeCN) as a novel molecular selenium source to synthesize Sb2Se3 uniform nanorods. The resulting nanorods have been carefully characterized and are found to exhibit decent photoconductivity as well as broad-spectrum optical absorption with an Eg value of ∼1.35 eV. A molecular reaction mechanism is rationally proposed and evidenced for forming Sb2Se3, which is related to the thermal decomposition of selenocyanate (SeCN−) anions through the cleaving of Se–CN bonds to elemental Se(0), followed by its reduction to Se2− anions. Our work using KSeCN offers an alternative method for the synthesis of metal selenides with desirable nanostructures and properties. [ABSTRACT FROM AUTHOR]

The Sn-NaY zeolite catalysts, Sn-NaY-gas and Sn-NaY-liq, were prepared by two-step post-synthesis methods, through hydrothermal dealumination and the post-incorporation of Sn species using chemical vapor deposition and impregnation separately. The Sn-ion incorporation and the physicochemical properties of the catalysts were characterized by various techniques. The amount of Sn species that were incorporated into the zeolite framework depended closely on the Sn introduction method. Sn-NaY-gas was found to have more Lewis-acid tetracoordinated Sn sites, which led to a better catalytic performance in the Baeyer-Villiger oxidation of cyclohexanone. The higher Sn loadings in the Sn-NaY-liq (3.4%) resulted in many inactive amorphous extra-framework Sn species, which also caused partial blockage of the zeolite pores and led to a loss in catalytic efficiency. Therefore, chemical vapor deposition could be used to form more active Lewis acidic Sn sites. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Semiconductor-sensitized TiO 2 thin films with long-term air stability are attractive for optoelectronic devices and applications. Herein, we demonstrate the potential of the TiO 2 thin film (∼800 nm in thickness) sensitized with a Sb 2 Se 3 layer (∼350 nm) grown from solution spin coating and processed by annealing recrystallization at 300 °C for high-performance optical detection. The type-II band alignment, p-Sb 2 Se 3 /n-TiO 2 heterojunction, and narrow band gap of Sb 2 Se 3 (∼1.25 eV) endow the film photodetector with a large photocurrent, high switching stability and on/off ratio (>10 3 ), and fast response speeds (<20 ms) under the broadband visible-near-infrared irradiation in a zero-bias self-powered photovoltaic mode. In particular, the photodetector shows notable resistance to oxidation and moisture for long-term operation, which is linked to the modest surface oxidation (Sb-O) of Sb 2 Se 3 , as verified by X-ray photoelectron spectroscopy. The first-principles calculations show that a low and medium concentration of oxygen substitution for Se (O Se ) and oxygen interstitial (O i ) with negative formation energies can lead to such a moderate surface oxidation but do not generate impurity states or just introduce a shallow-level acceptor state in the electronic structures of Sb 2 Se 3 without degrading its optoelectronic performance. Our theoretical results offer a rational explanation for the air-stable and oxidation/moisture-resistant characteristics in moderately oxidized Sb 2 Se 3 and may shed light on the surface oxidation-property relationship studies of other nonoxide semiconductor-sensitized devices.

Nanoscale chemical transformations based on partial cation exchange reactions are known as a component-increased, shape-maintaining means for the design and tunable preparation of ternary or multinary metal chalcogenide compounds. Herein, we present a new material couple, Bi 2 S 3 -AgBiS 2 , to detail the binary-ternary chemical transformation via partial cation exchange and its reaction thermodynamics and kinetics. The preformed Bi 2 S 3 nanorods (NRs) act as both the reactant and the parent template, within which the partial exchange of Bi 3+ with Ag + cations proceeds under a silver-rich, diffusion-controlled regime, leading to the formation of energetically favorable AgBiS 2 . The NR shape preservation involving sulfur sublattice rearrangement is due to the proper diameter thickness (∼12 nm) of parent Bi 2 S 3 NRs and the rapid establishment of equilibrium-phase AgBiS 2 , as supported by X-ray diffraction measurements and the pseudobinary Ag 2 S-Bi 2 S 3 phase diagram. Interestingly, the finding of a AgBiS 2 -Bi 2 S 3 -AgBiS 2 intermediate with axially segmented heterostructures reveals the real NR-to-NR conversion trajectory and the shape-induced exchange reaction anisotropy at the ends and middle of Bi 2 S 3 NRs. Additionally, the resultant AgBiS 2 NRs with a measured band gap of ∼0.86 eV exhibit potential for photoelectronic applications because of their impressive visible-near-infrared absorption and photoconductivity.