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Aims: Secondary bleeding and further hematoma expansion (HE) aggravate brain injury after intracerebral hemorrhage (ICH). The majority of HE results from hypertensive ICH. Previous study reported higher iron content in the brains of hypertensive patients. Iron overload exacerbates the risk of hemorrhagic transformation in thromboembolic stroke mice. Whether iron overload during the process of hypertension participates in secondary bleeding of hypertensive ICH remains unclear. Methods: Hypertension was induced by continuous infusion of angiotensin II (Ang II) with an osmotic pump into C57BL/6 mice. ICH was simulated by intrastriatal injection of the liquid polymer Onyx‐18. Iron chelation and iron overload was achieved by deferoxamine mesylate or iron dextran injection. Secondary bleeding was quantified by measuring the hemoglobin content in the ipsilateral brain hemisphere. Results: Ang II‐induced hypertensive mice showed increased iron accumulation in the brain and expanded secondary hemorrhage after ICH modeling. Moreover, iron chelation suppressed while iron overload aggravated secondary bleeding. Mechanistically, iron exacerbated the loss of contractile cerebral vascular smooth muscle cells (VSMCs), aggravated blood–brain barrier (BBB) leakage in Ang II‐induced hypertensive mice, and increased glial and MMP9 accumulation after ICH. Conclusion: Iron overload plays a key role in secondary bleeding after ICH in Ang II‐induced hypertensive mice. Iron chelation during the process of Ang II‐induced hypertension suppresses secondary bleeding after ICH. [ABSTRACT FROM AUTHOR]

Background: Inflammation plays an essential role in secondary brain injury after intracerebral hemorrhage (ICH). Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II receptor blockers (ARBs) have been suggested to suppress neuroinflammation after central nervous system (CNS) damage in animal models. However, the role of ACEIs and ARBs in ICH patients with hypertension remains unresolved in clinic. The aim of the present study is to evaluate the effect of ACEIs/ARBs on ICH patients with hypertension using a retrospective, single-center data analysis. Methods: ICH patients diagnosed by computerized tomographic (CT) at Southwest Hospital, Third Military Medical University were included in the present research from January 2015 to December 2019. According to the medical history for the usage of antihypertensive drugs, patients were assigned into either ACEIs/ARBs group or non-ACEIs/ARBs group. Demographics, clinical baseline, radiological documents and treatments were collected and these data were statistically analyzed between the two groups. Results: A total of 635 ICH patients with hypertension were included and allocated into 2 groups according to the usage of antihypertensive drugs: 281 in the ACEIs/ARBs group and 354 in the non-ACEIs/ARBs group. The results presented that the 3-months mortality and prevalence of ICH-associated pneumonia were lower in ACEIs/ARBs group than that in non-ACEIs/ARBs group (5.0% vs 11.9%, p=0.002; 58.4% vs 66.7%, p=0.031). While, there was no significant difference in favorable outcome (40.2% vs 33.9%, p=0.101) between the two groups. Furthermore, patients in ACEIs/ARBs group exhibited significantly less perihematomal edema volume on days 3 (23.5 ± 14.4 versus 28.7 ± 20.1 mL, p=0.045) and 7 (21.0 ± 13.7 versus 25.7 ± 17.6 mL, p=0.044), compared to that in non- ACEIs/ARBs group. Conclusion: The usage of ACEIs/ARBs helps decrease mortality, perihematomal edema volume, and prevalence of ICH-associated pneumonia in ICH patients with hypertension. [ABSTRACT FROM AUTHOR]

Aims: Hypertension is a leading cause of cerebral small vessel disease (CSVD). Currently, treatments for CSVD are limited. Nicotinamide riboside (NR) can protect against vascular injury and cognitive impairment in neurodegenerative diseases. In this study, the protective effects of NR against angiotensin ‐ (Ang ‐)–induced CSVD were evaluated. Methods: To explore the effects of NR in CSVD, C57BL/6 mice were infused with Ang ‐, and NR was added to the food of the mice for 28 days. Then, short‐term memory, blood‐brain barrier (BBB) integrity, and endothelial function were detected. Arteriole injury and glial activation were also evaluated. Results: Our data showed that mice infused with Ang ‐ exhibited decreased short‐term memory function and BBB leakage due to decreased claudin‐5 expression and increased caveolae‐mediated endocytosis after 28 days. Furthermore, Ang ‐ decreased the expression of α‐smooth muscle actin (α‐SMA) and increased the expression of proliferating cell nuclear antigen (PCNA) in arterioles and decreased the expression of neurofilament 200 (NF200) and myelin basic protein (MBP) in the white matter. These CSVD‐related damages induced by Ang ‐ were inhibited by NR administration. Moreover, NR administration significantly reduced glial activation around the vessels. Conclusion: Our results indicated that NR administration alleviated Ang ‐–induced CSVD by protecting BBB integrity, vascular remodeling, neuroinflammation, and white matter injury (WMI)–associated cognitive impairment. [ABSTRACT FROM AUTHOR]

Abstract: Uniform MoS2 nanosheets/C hybrid microspheres with mean diameter of 320nm have been successfully synthesized via a facile one-pot hydrothermal route by sodium molybdate reacting with sulfocarbamide in d-glucose solutions. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). XRD patterns showed that the MoS2 was kept as a two-dimensional nanosheet crystal and C was retained as amorphous even after their annealing treatment at 800°C. TEM and SEM images indicated that the MoS2 nanosheets were uniformly dispersed in the amorphous carbon. The experiment results also revealed that the appropriate amount of d-glucose had an obvious effect on the formation of uniform MoS2 nanosheets/C hybrid microspheres. A possible formation process of MoS2 nanosheets/C hybrid microspheres was preliminarily presented. [Copyright &y& Elsevier]

Abstract: SnS2/SnO2 composites were prepared in a microwave-assisted reaction of a mixture solution of SnCl4 and l-cysteine and were characterised by XRD, TEM, SEM and EDX. The influence of the mole ratio of SnCl4 to l-cysteine (l-cys) on the sample was investigated. It was found that using a microwave method, SnS2/SnO2 composites were formed, and SnS2/SnO2 nanoparticles were obtained when the mole ratio of SnCl4 to l-cysteine was 1:2. With higher contents of l-cys, when the mole ratio of SnCl4 to l-cys was 1:4, the products were nanosheets instead of nanoparticles. Electrochemical tests demonstrated that the SnS2/SnO2 composites with layer structure exhibited high reversible capacities and good cycling performances when used as anode materials of Li-ion batteries. When the mole ratio of SnCl4 to l-cys was 1:6, the initial reversible capacity of products was 593mAh/g, and the retention capacity that was maintained was over 88%. Besides, the retention capacity of products was still excellent at high current charge/discharge. [Copyright &y& Elsevier]

Abstract: MoS2 nanostructures with different morphologies, such as agaric-like, sphere-like and flower-like, were successfully synthesized via a facile ionic liquid-assisted hydrothermal route. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), Raman spectroscopy and energy dispersive X-ray analysis (EDX). XRD patterns showed that the layered structures of the as-prepared MoS2 samples did not completely form, and after their annealing treatment at 800°C for 2h in the atmosphere of N2/H2, the MoS2 products had good crystallinities with well-stacked layered structures. The influences of the ionic liquid on the sizes and morphologies of the MoS2 nanostructures were discussed. It was found that the as-prepared MoS2 nanostructures were assembled by nanosheets and the ionic liquid played a crucial role on the formation of the MoS2 nanostructures in our experiment. A possible formation mechanism of the sphere-like MoS2 nanostructures was preliminarily presented. [Copyright &y& Elsevier]

Abstract: A facile hydrothermal route assisted by Na2H2EDTA (ethylenediaminetetraacetic acid disodium) has been successfully developed to prepare uniform cerium phosphate (CePO4) aggregates with different morphologies, such as peanut-like and spindle-like. It was found that the as-prepared uniform CePO4 aggregates were constructed with many nearly parallel aligned nanorods. The molar ratio of EDTA/Ce3+, solution pH and reaction time had great influences on the morphologies and sizes of the CePO4 samples. In our process of synthesis, Na2H2EDTA played important roles as complexing reagent and inducing agent on the formation of CePO4 aggregates. The possible growth mechanism for CePO4 aggregates was presented. Ce0.9Tb0.1PO4 aggregates with different morphologies were also prepared and their photoluminescence properties were characterized. [Copyright &y& Elsevier]

Abstract: Highly uniform and monodisperse disk-like CeF3 particles with diameter about 230 nm and thickness about 76 nm were successfully synthesized via a mild and facile microwave irradiation assisted by a complexing reagent, ethylenediamine tetraacetic acid disodium salt (Na2H2EDTA). The morphologies and crystal structure of the products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and scanning electron microscopy (SEM). XRD patterns showed that the as-prepared CeF3 products have hexagonal structure and high crystallinity. SEM images showed that these disk-like CeF3 nanocrystals had rough surfaces which were covered with many sheet-like structures. It was found that the reaction time and the complexing reagent played crucial roles on formation of uniform disk-like CeF3 particles. A possible formation mechanism of the disk-like CeF3 particles was preliminarily presented. [Copyright &y& Elsevier]

Abstract: High-purity Pr(OH)3 nanorods with uniform diameter were synthesized in large scale by microwave-assisted heating method, and Pr6O11 nanorods were obtained by subsequent thermal decomposition of the as-prepared Pr(OH)3 nanorods at 500°C for 6h. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). It was found that the hydroxide nanorods with hexagonal phase and oxide nanorods with cubic phase have high crystallinity and purity. The influences of the KOH concentration and microwave heating time on the size and morphologies of Pr(OH)3 nanorods were discussed. The mechanism for the formation of Pr(OH)3 nanorods under microwave heating process was preliminarily proposed. [Copyright &y& Elsevier]

Abstract: PrF3 hollow nanoparticles were synthesized by the microwave-assisted heating hydrothermal treatment of the corresponding colloidal rare earth fluorides precipitates. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM). The TEM imaging showed that the PrF3 nanoparticles prepared in this way had hollow sphere-like morphology with the mean particle size of about 31 nm. XRD showed that the PrF3 hollow nanoparticles had high purity and high crystallinity. [Copyright &y& Elsevier]

Abstract: The 31Δg and 41Δg Rydberg states of Na2, which dissociate to Na(3s)+Na(4d) and Na(3s)+Na(4f), respectively, have been observed by using high-resolution cw optical–optical double resonance spectroscopy. The potential minima of these two states are separated by 129.74cm−1 and they have an avoided crossing at 4.09Å implying significant interaction making them a pair of twins. The results of our observation agree very well with the ab initio calculations. [Copyright &y& Elsevier]

Abstract: The Ru/C nanocomposites with Ru loadings of 20∼60 wt.% were prepared by the polyol process in the presence of XC-72 carbon. TEM observations indicated that Ru nanoparticles were uniform with the average size of about 3.1∼3.5 nm, and highly dispersed on the carbon surface. After electrochemically oxidization from Ru nanoparticles to the pseudocapacitive oxide–hydroxide form, the specific capacitances of these composites were calculated by cyclic voltammetry. It was found that these composites exhibited much higher specific capacitances in comparison with the XC-72 carbon. [Copyright &y& Elsevier]

Pt and PtRu nanoparticles supported on HNO3-treated carbon nanotubes (CNTs) were prepared by microwave-assisted heating of polyol process and characterized by XRD and TEM. It was found that the metal nanoparticles were uniform in shape and size and well dispersed on the carbon nanotubes. The average metal diameters were about 3.0–3.1 nm for Pt and 2.8 nm for PtRu. [Copyright &y& Elsevier]

Nanocomposites of carbon nanotubes (CNTs) with Sb and SnSb0.5 particles were prepared by chemical reduction of SnCl2 and SbCl3 precursors in the presence of CNTs. SEM and TEM imaging showed that the Sb and SnSb0.5 particles are uniformly deposited on the CNT exterior and in the CNT web. These CNT–metal composites are active anode materials for lithium ion batteries, showing improved cyclability compared to unsupported Sb and Sn–Sb particles and higher reversible specific capacities than CNTs. The reversible capacities were as high as 462 mAh/g for CNT–36 wt.% Sb and 518 mAh/g for CNT–56 wt.% SnSb0.5. After 30 cycles, the capacity was 62.1% of the initial capacity for the former and 67.2% of the initial capacity for the later. In comparison Sb and SnSb0.5 could only retain 17.7 and 23.5%, respectively of their initial capacities in the same number of cycles. The improvement in cyclability may be attributed to the nanoscale dimension of the metal particles and CNTs’ role as a buffer in relieving the mechanical stress induced by specific volume changes in electrochemical lithium insertion and extraction reactions. [Copyright &y& Elsevier]

Nanocomposites of carbon nanotubes (CNTs) with Sn2Sb alloy nanoparticles were prepared by KBH4 reduction of SnCl2 and SbCl3 precursors in the presence of CNTs. SEM and TEM examinations showed that most of the Sn–Sb alloy nanoparticles were present in high dispersion in the CNT web, while others were deposited directly on the outside surface of the carbon nanotubes. Constant current charge and discharge tests using the nanocomposites as Li+ storage compounds showed higher specific capacities than pristine CNTs and better cyclability than unsupported Sn2Sb particles. The first cycle de-lithiation capacity of 580 mAh/g from a CNT–56 wt%Sn2Sb nanocomposite was nevertheless reduced to 372 mAh/g after 80 deep charge and discharge cycles. The uniform dispersion of Sn2Sb alloy in the CNT web and on the surface of CNTs have substantially improved the usability of the Sn2Sb particles to the extent that the nanocomposites of CNTs and Sn2Sb may be considered as a candidate anode material for Li-ion batteries. [Copyright &y& Elsevier]

Abstract: Novel flower-like CeF3 nanostructures with a mean diameter of 190nm were successfully synthesized via a rapid and facile microwave irradiation route using ethylenediaminetetraacetic acid disodium as the complexing reagent. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and photoluminescence (PL). XRD patterns showed that the CeF3 nanoflowers were hexagonal phase and had good crystallinity and purity. TEM and SEM images showed that the as-prepared CeF3 samples displayed 3D flower-like nanostructures and had uniform sizes and morphologies. The experimental results revealed that the as-prepared CeF3 nanoflowers might be assembled by nanodisks. The formation process of the CeF3 nanoflowers was preliminarily investigated. [Copyright &y& Elsevier]

Abstract: MoS2 microspheres were successfully synthesized via a facile hydrothermal route assisted by an ionic liquid [BMIM][BF4]. The products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). XRD patterns showed that the layered structure of the as-prepared MoS2 did not completely form, and after their annealing at 800 °C for 2 h in the atmosphere of N2/H2, the MoS2 microspheres had good crystallinity with well-stacked layered structure. SEM images showed that the MoS2 microspheres had uniform sizes with mean diameter about 2.1 μm. The MoS2 microspheres had rough surfaces and were constructed with sheet-like structures. Ionic liquid played a crucial role as a templating reagent in the formation of MoS2 microspheres. A possible formation mechanism of MoS2 microspheres was preliminarily presented. [Copyright &y& Elsevier]

Abstract: LaPO4:Re (Re=Ce3+, Eu3+ and Tb3+) nanorods have been successfully synthesized on a large scale by a facile and rapid microwave heating method. The structure, morphology and physical properties of the as-prepared products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and photoluminescence spectroscopy (PL). XRD patterns showed that the as-prepared products had hexagonal structure and high crystallinity and purity. TEM images showed that these LaPO4:Re nanorods have a high yield and an obvious one-dimensional structure with diameter from 6 nm to 30 nm and length up to 400 nm. The luminescence spectra of the products indicated that different rare-earth ions had been successfully doped in LaPO4 matrix via the microwave heating method and the actual doping amounts of Re ions were determined by the inductively coupled plasma (ICP). [Copyright &y& Elsevier]

Abstract: MoS2/C nanocomposites were synthesized by a facile hydrothermal route employing sulfocarbamide, sodium molybdate and D-grouse as starting materials. XRD analysis showed that the MoS2 was a two-dimensional nanosheet crystal and C was retained as amorphous after their calcinations at 800 °C. TEM images showed that MoS2 was uniformly dispersed in the amorphous carbon. The MoS2/C composites exhibited high reversible capacity and excellent cyclic performance when used as Li-intercalation electrodes. The improvements in electrochemical performance are attributed to the incorporation of amorphous carbon, which can suppress the aggregation and pulverization of active materials, and keep the active materials electrically connected. [Copyright &y& Elsevier]

MoS 2 microflowers are fabricated by a facile hydrothermal route with polyquaternary ammonium salt (Polyquaternium-11, PQA) as a soft template. The experimental results indicate that the MoS 2 microflowers are of hexagonal phases and have a hierarchical flower-like morphology, which are assembled by numerous few-layered nanosheets. A probable assembly process is proposed to illustrate the formation of the MoS 2 microflowers. Additionally, as an electrode material for supercapacitor, the resultant MoS 2 microflowers demonstrate a superior electrochemical property which could be attributed to their robust hierarchical architectures and few-layered feature. [ABSTRACT FROM AUTHOR]

Abstract: A B2O3-doped SnO2 thin film was prepared by a novel experimental procedure combining the electrodeposition and the hydrothermal treatment, and its structure and electrochemical properties were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) analysis, energy dispersive X-ray (EDX) spectroscopy and galvanostatic charge–discharge tests. It was found that the as-prepared modified SnO2 film shows a porous network structure with large specific surface area and high crystallinity. The results of electrochemical tests showed that the modified SnO2 electrode presents the largest reversible capacity of 676mAhg−1 at the fourth cycle, close to the theoretical capacity of SnO2 (790mAhg−1); and it still delivers a reversible Li storage capacity of 524mAhg−1 after 50 cycles. The reasons that the modified SnO2 film electrode shows excellent electrochemical properties were also discussed. [Copyright &y& Elsevier]

Abstract: Flower-like MoS2 microspheres with high purity were successfully synthesized via a facile hydrothermal route by adding sodium silicate as an additive. The products were characterized by X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). XRD patterns showed that the MoS2 microspheres had good crystallinity with well-stacked layered structure. TEM and SEM images showed that the MoS2 microspheres had uniform sizes with mean diameter about 480 nm and were constructed with MoS2 sheets with thickness of several nanometers. It was found that the possible precursor H4SiMo12O40 obtained by sodium silicate reacting with sodium molybdate played a crucial role in the formation of the flower-like MoS2 microspheres in our experiment. A possible formation mechanism of MoS2 microspheres was preliminarily presented. [Copyright &y& Elsevier]