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Pulmonary arterial hypertension (PAH) is a disease in which stenosis or obstruction of the pulmonary arteries (PAs) causes an increase in PA pressure, leading to right-sided heart failure and death. Basic research has revealed a decrease in the levels of endogenous vasodilators, such as prostacyclin, and an increase in the levels of endogenous vasoconstrictors, such as endothelin, in patients with PAH, leading to the development of therapeutic agents. Currently, therapeutic agents for PAH target three pathways that are selective for PAs: the prostacyclin, endothelin, and nitric oxide pathways. These treatments improve the prognosis of PAH patients. In this review, we introduce new drug therapies and provide an overview of the current therapeutic agents. [ABSTRACT FROM AUTHOR]

The surface potentials and local conductivity of self-assembled monolayers (SAMs) formed using aromatic molecules covalently bonded to n-type silicon (111) via Si–C and Si–O bonds were measured using Kelvin probe force microscopy (KPFM) and conductive AFM (CAFM). Surface potential measurements were done using micropatterned SAMs with hexadecyl SAM as a reference to eliminate surface potential variations due to the cantilever tips. Micropatterning was conducted via vacuum ultraviolet photolithography at λ = 172 nm. Ellipsometry, X-ray photoelectron spectroscopy, static water contact angle and atomic force microscopy tests show that the aromatic SAMs were well-organized despite the short molecular lengths of the precursors. KPFM results show that Si–C bonded SAMs have higher surface potentials compared to Si–O SAMs, which is in agreement with dipole moments estimated by Molecular Orbital Package semi-empirical computations. CAFM scans showed conductive domains for the aromatic SAM regions, and Si–O SAMs exhibited a higher current than Si–C SAMs. [ABSTRACT FROM AUTHOR]

Electrochemical exfoliation of graphite is a method for synthesizing graphene oxide (GO) with fewer structural defects than GO synthesized by conventional chemical oxidation. Photoreduction of GO has been focused on due to their facile procedures, and environmental friendliness. In this report, electrochemically-exfoliated graphene oxide (EGO) was irradiated by vacuum ultraviolet (VUV) light at 140 °C under a high vacuum environment, named thermal-assisted VUV light treatment. Conductive atomic force microscopy was used to investigate the electrical characteristics of individual sheets on the nanometer scale. The electrical conductivity of the treated sheet (1.4 × 105 S m−1) was higher than the pristine EGO by an order of magnitude. The chemical and structural analysis showed that the EGO was reduced and their π -conjugated domains were restored through a hybrid of photochemical and thermal treatment. These results indicate that our hybrid approach has the potential for reducing the EGO. [ABSTRACT FROM AUTHOR]

Water-in-salt (WiS), which contains salt with a high salt concentration (>5 mol kg−1), is attractive for novel electrolytes in electrochemical applications such as lithium-ion batteries and electrochemical deposition because of its high electrochemical stability. Structural analysis on the WiS/solid interfaces would be beneficial for understanding these processes. In this study, we investigated interfacial solvation structures of WiSs by frequency modulation atomic force microscopy utilizing a quartz tuning fork sensor. Two types of WiSs, a lithium bis(trifluoromethanesulfonyl) imide (LiTFSI)-WiS and a LiCl-WiS, were prepared. We found that the interfacial solvation structures of the WiSs on mica surfaces were quite different by using a 2D frequency shift mapping technique. We discussed the differences in their interfacial solvation structures by comparing their bulk solution properties measured by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Ionic liquid (IL)/solid interfaces are relevant to a broad range of physicochemical phenomena and technological processes such as catalysis, corrosion, electrochemistry, and lubrication. Hence, understanding the effect of substrate surface nature on the interfacial properties has a significant impact on improving technological processes in which interfacial properties are dominant. In this work, we investigated interfacial structures between 1-butyl-3-methylimidazolium hexafluorophosphate (BMI-PF6) IL and KBr crystal surfaces by frequency modulation atomic force microscopy utilizing a quartz tuning fork sensor. KBr(100) and (111) surfaces were used as the substrates, where the (100) surface is electrically neutral, and the (111) surface is highly charged. We investigated the influence of surface charge on their surface structures and interfacial solvation structures by atomic-scale topographic imaging and frequency shift versus distance curve measurement. The behavior of IL at these two interfaces was found to be significantly different due to these different surface properties. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) form layered solvation structures at IL/electrode interfaces relevant to many electrochemical applications. Recently, we observed a partially disturbed solvation structure at the 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI)/spinel lithium titanate oxide (Li4Ti5O12, LTO) electrode interface containing Li-salt and considered the Li+-ion transfer occurring at the interface as one plausible reason for this partial destruction. In this study, we investigated EMI-TFSI/LTO(111) interfaces with the addition of K-salt or Mg-salt by frequency modulation atomic force microscopy utilizing a quartz tuning fork. It is assumed that no ion-transfer occurs at these two interfaces. The laterally consecutive solvation structures were observed at both interfaces, which strongly supported our hypothesis. Additionally, a kink in the solvation structure was observed at the interface containing Mg-salt. These results offer a comprehensive understanding of the perplexing IL/electrode interfaces with an addition of metal salt. [ABSTRACT FROM AUTHOR]

Chemical etching of silicon assisted by a number of catalysts is attracting increasing attention in the fabrication of silicon micro–nanostructures. In practical applications, metal-free catalysts, including carbon materials, have been focused on as alternative materials for the assisted etching of silicon. Although this anisotropic etching process is suitable for the fabrication of silicon micro–nanostructures due to its simplicity and cost effectiveness, a number of challenges remain, such as the formation of a porous layer and peeling of the catalyst by the gases produced during the etching process. We herein report vapor-phase etching assisted by graphene oxide and its mechanism in terms of reaction kinetics. By optimizing etching conditions, graphene oxide enhances the etching reaction in the vapor phase without the formation of a porous layer. We also demonstrated the formation of micrometer-sized pores in the desired areas by combining the microcontact printing of graphene oxide with silicon etching in the vapor phase. [ABSTRACT FROM AUTHOR]

A method whereby several molecules can be arranged at one time onto spatially defined positions in the near-molecular scale, is reported. The approach is based on scanning probe lithography (SPL) with self-assembling of organosilane molecules. The SPL process was used to locally remove a trimethylsilyl ((CHsub3)sub3Si-), TMS monolayer on a silicon substrate.

This study aimed at identifying the clinical characteristics and in-hospital outcomes of patients treated with polytetrafluorethylene (PTFE)-covered stents after coronary interventions in a multicenter registry. Subjects with coronary artery perforation were selected from 31,262 consecutive patients who underwent coronary interventions in the hospital registries. Subjects were divided into two groups: those with a PTFE-covered stent implantation and those without a PTFE-covered stent implantation. Clinical characteristics and in-hospital outcomes were compared between the two groups. Data for 82 consecutive coronary perforations (15 PTFE-covered stents and 67 non-PTFE-covered stents) were extracted from each hospital registry. The PTFE-covered stent group had a higher prevalence of perforations due to pre-dilatation before stenting or post-dilatation after stenting (80% vs. 10.4%; p < 0.001), more Ellis classification III perforations (66.6% vs. 28.4%; p = 0.019), longer perforation to hemostasis time (74 min vs. 10 min; p < 0.001), lower hemostatic success rates (73.3% vs. 94.0%; p = 0.015), and higher in-hospital mortality (26.7% vs. 6.0%; p = 0.015) than the non-PTFE-covered stent group. Although the prevalence of intravascular ultrasound (IVUS) usage was high during coronary interventions (86.7%), IVUS was performed in less than half the cases just before coronary perforations (47%) in the PTFE-covered stent group. Patients requiring PTFE-covered stents are more likely to be observed after balloon dilatation before or after stenting and have a poor prognosis. Careful coronary intervention is needed when IVUS image acquisition is not achieved in addition to proper evaluation of IVUS. Furthermore, if coronary artery perforation occurs, it is important to determine the need for a prompt PTFE-covered stent. [ABSTRACT FROM AUTHOR]

Ionic liquids (ILs) have been intensively studied as one promising candidate for an electrolyte in lithium ion batteries (LIBs). Structural analysis of interfaces between an IL-based electrolyte and a LIB electrode would provide beneficial information for improving LIBs. In this study, we investigated the interfacial structures between an IL, 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl)imide (EMI-TFSI), and a spinel-type lithium titanate (Li4Ti5O12) electrode in the presence and absence of Li-salt by frequency modulation atomic force microscopy (FM-AFM) utilizing a quartz tuning fork sensor. Solvation structures on the interface were successfully visualized by two-dimensional frequency shift mapping. Electrochemical impedance spectroscopy measurement was also performed to measure the rate of Li+-ion insertion/extraction on the interface and we found that the interfacial ion-transfer may prevent the formation of layered solvation structure. [ABSTRACT FROM AUTHOR]

Surface potential contrasts were measured for n-type silicon (111) modified with 1-alkene self-assembled monolayers (SAMs) of varying hydrocarbon chain lengths (n = 10–20) using Kelvin probe force microscopy (KPFM). Micropatterned SAMs were used in KPFM analysis, with hexadecyl SAM acting as a reference to avoid possible variations due to different KPFM cantilever tips used for analysis. Micropatterning was performed via vacuum ultraviolet photolithography at λ = 172 nm. Individual samples were also analyzed by ellipsometry, X-ray photoelectron spectroscopy, static water contact angle tests and atomic force microscopy to determine SAM quality. Surface potential changes observed between the different SAMs were attributed to differences in the dipole moment of the precursor molecules, changes in SAM dielectric properties due to differences in molecular packing, and varying oxygen content at the surface. [ABSTRACT FROM AUTHOR]

Soaking of an irradiated sample in an aqueous solution of dye molecules facilitates the selective incorporation of dye molecules on the laser fabricated surface of poly(methyl methacrylate), with laser fluence controlling the selectivity. ESR spectroscopic study identifies a metastable molecular species of a propagating radical in the irradiated sample and X-ray photoelectron spectroscopy reveals the presence of oxygen containing-compounds. Only cationic dye molecules are incorporated due to the interaction with polar chemical species on the fabricated surface.