BACKGROUND: Despite recent advances the prognosis of pulmonary hypertension remains poor and warrants novel therapeutic options. Extensive studies, including ours, have revealed that hypoxia-induced pulmonary hypertension is associated with high oxidative stress. Cerium oxide nanozyme or nanoparticles (CeNPs) have displayed catalytic activity mimicking both catalase and superoxide dismutase functions and have been widely used as an anti-oxidative stress approach. However, whether CeNPs can attenuate hypoxia-induced pulmonary vascular oxidative stress and pulmonary hypertension is unknown.
RESULTS: In this study, we designed a new ceria nanozyme or nanoparticle (AuCeNPs) exhibiting enhanced enzyme activity. The AuCeNPs significantly blunted the increase of reactive oxygen species and intracellular calcium concentration while limiting proliferation of pulmonary artery smooth muscle cells and pulmonary vasoconstriction in a model of hypoxia-induced pulmonary hypertension. In addition, the inhalation of nebulized AuCeNPs, but not CeNPs, not only prevented but also blunted hypoxia-induced pulmonary hypertension in rats. The benefits of AuCeNPs were associated with limited increase of intracellular calcium concentration as well as enhancement of extracellular calcium-sensing receptor (CaSR) activity and expression in rat pulmonary artery smooth muscle cells. Nebulised AuCeNPs showed a favorable safety profile, systemic arterial pressure, liver and kidney function, plasma Ca2+ level, and blood biochemical parameters were not affected.
CONCLUSIONS: We conclude that AuCeNPs is an improved reactive oxygen species scavenger that effectively prevents and treats hypoxia-induced pulmonary hypertension.

The damage threshold of an Au-coated flat mirror, one of the reflective optics installed on the FEL-2 beamline of the Dalian Coherent Light Source, China, upon far-UV free-electron laser irradiation is evaluated. The surface of the coating is characterized by profilometer and optical microscope. A theoretical approach of the phenomenon is also presented, by application of conventional single-pulse damage threshold calculations, a one-dimensional thermal diffusion model, as well as finite-element analysis with ANSYS.

The application of Neurospora sp., a fungus that commonly thrives on complex agricultural and plant wastes, has proven successful in utilizing citrus peel waste as a source of naringin. A UV-Vis spectrophotometric method proved the biotransformation of naringin, with an absorption maximum (λmax) observed at 310 nm for the biotransformed product, naringenin (NAR). Further verification of the conversion of naringin was provided through thin layer chromatography (TLC). The Neurospora crassa mediated biotransformation of naringin to NAR was utilized for the rapid (within 5 min) synthesis of silver (Ag) and gold (Au) nanoconjugates using sunlight to accelerate the reaction. The synthesized NAR-nano Ag and NAR-nano Au conjugates exhibited monodispersed spherical and spherical as well as polygonal shaped particles, respectively. Both of the nanoconjugates showed average particle sizes of less than 90 nm from TEM analysis. The NAR-Ag and NAR-Au nanoconjugates displayed potential enhancement of the antimicrobial activities, including antibacterial and nematicidal properties over either standalone NAR or Ag or Au NPs. This study reveals the potential of naringinase-producing Neurospora sp. for transforming naringin into NAR. Additionally, the resulting NAR-Ag and NAR-Au nanoconjugates showed promise as sustainable antibiotics and biochemical nematicides.

MnPt\'s exceptional stability and extremely high Néel temperature have generated a lot of interest in data storage applications. Previously, it was reported experimentally that the MnPt alloy shows ferromagnetic (FM) behavior at room temperature. In this study, the effects of partial substitution of Pt with Pd, Au, and Ag on magnetic properties is investigated using density functional theory. The stability of Mn50Pt50-xMx (M = Pd, Au, Ag, x = 6.25, 12.5, 18.75) alloys was assessed by determining their thermodynamic, magnetic, and mechanical properties. The calculated lattice constants of Mn50Pt50 agree well with available theoretical results. The Mn50Pt50-xMx alloys\' formability was assessed by measuring the thermodynamic stability using the heat of formation. It was found that B2 Mn50Pt50-xPdx alloys (0 ≤ x ≤ 18.75) are thermodynamically stable due to the negative heat of formation close to that of a pristine MnPt alloy. Based on the elasticity results, the B2 Mn50Pt50-xPdx is most likely to undergo martensitic transformation for the entire considered composition range. From the calculated values of the Poisson\'s ratio, it is shown that an increase in Pd, Ag, and Au effectively improves the ductility of the B2 Mn50Pt50-xMx compounds. It was revealed that ferromagnetism is maintained with Pd addition but significantly reduced in the case of Au and Ag. Thus, this work showed that density functional theory can be exploited to propose new possible compositions for future magnets in spintronic applications.

The current binary understanding of membership in international organizations (IOs), especially regional organizations (ROs), creates blind spots and biases in our understanding of who matters in IOs, as well as why and how they matter. Existing scholarship primarily looks at full member-states or non-state actors to capture who influences such organizations. Associated states are often portrayed as passive receivers of IO rules instead of active contributors. We address this blind spot and resulting analytical bias by exploring what types of association relationships exist and how they impact IOs. We propose a novel conceptualization of membership that we call memberness. On the level of IOs, memberness is based on the relative openness of organizational boundaries and stratified access via material and ideational contributions. On the level of states, memberness captures associated states\' individual choices to contribute materially and/or ideationally to an IO. Memberness moves away from a purely rights-based understanding of membership (or who you are in an IO) to include a capacity-based understanding (or what you do in an IO). This shift in focus uncovers new channels of influence on IOs. Associated states\' material and ideational contributions to IOs constitute three memberness types: payroller, sponsor, and advisor. We argue that these memberness types impact IOs\' vitality, design, and performance in previously unrecognized ways. We illustrate these types with empirical examples from ROs across the globe and discuss the implications of memberness for IO research programs.

Photocatalytic CO2 conversion is a prospective way to mitigate greenhouse effect. In2O3 is widely used in the resource conversion of CO2, but still exists a few drawbacks containing limited CO2 capture and activation, narrow light absorption range, low charge separation and utilization. To overcome these disadvantages, an NH2-UiO-66/Au/In2O3 composite photocatalyst is built, with Au nanoparticles and NH2-UiO-66 decorated on the surface of In2O3 nanorods. Significantly, the improved carrier separation ability is attributed to the Schottky junction at the Au/In2O3 interface and the heterostructure between In2O3 and NH2-UiO-66. And the widened light absorption is attributed to the plasmon effect caused by Au nanoparticles. Moreover, the increase of CO2 adsorption and activation is mainly due to the porosity of NH2-UiO-66, thereby greatly improving photocatalytic CO2RR efficiency of NH2-UiO-66/Au/In2O3 nanorods. The CO yield of NH2-UiO-66/Au/In2O3 is 8.56 μmol g-1 h-1, which is nearly 45 times that of In2O3. This work will present a novel idea to design high-efficient composite photocatalysts for CO2 reduction by multifunctional component synergistic enhancement.

Plasmonic metal-semiconductor hybrid photocatalysts have received much attention because of their wide light harvesting range and efficient charge carrier generation capability originating from plasmon energy transfer. Here, we introduce a plasmonic metal-semiconductor hybrid nanostructure consisting of a Au core-satellite assembly and crystalline TiO2. The formation of Au@TiO2-Au core-satellite assemblies using TiO2 as a spacer and the subsequent growth of outer TiO2 shells on the core-satellite assemblies, followed by calcination, successfully generated Au core-satellite assembly@TiO2 nanostructures. Exquisite control over the growth of the TiO2 interlayer enabled the regulation of the gap distance between the core and satellite Au nanocrystals within the same hybrid morphology. Due to the structural controllability of the present approach, the gap-distance-dependent plasmonic and photocatalytic properties of the hybrid nanostructures could be explored. The nanostructures possessing the most closely arranged Au nanocrystals showed high photocatalytic activity under visible to near-infrared light irradiation, which can be attributed to strong plasmon coupling between the core and satellite Au nanocrystals that can expedite the formation of intense plasmon energy and its transfer to TiO2.

Full and partial restorations in dentistry must replicate the characteristics of the patient\'s natural teeth. Materials must have good mechanical properties and be non-toxic and biocompatible. Microbes, which can form biofilms, are constantly in contact with restorations. In this study, we investigate how well Candida albicans adheres to a polymethyl methacrylate (PMMA) resin base with gold (Au) nanoparticles. We synthesized Au nanoparticles and characterized them. The average size of Au nanoparticles embedded in PMMA was 11 nm. The color difference ΔE between PMMA and PMMA/Au composites was 2.7 and was still esthetically acceptable to patients. PMMA/Au surfaces are smoother and more hydrophilic than pure PMMA surfaces, and the isoelectric point of both types of surfaces was 4.3. Above the isoelectric point, PMMA/Au surfaces are more negatively charged than PMMA surfaces. The added Au nanoparticles decreased the tensile strength, while the hardness did not change significantly. Adhesion measurements showed that PMMA surfaces modified with Au nanoparticles reduced the extent of microbial adhesion of Candida albicans.

Au decorated with type I collagen (Col) was used as a core material to cross-link with stromal cell-derived factor 1α (SDF1α) in order to investigate biological performance. The Au-based nanoparticles were subjected to physicochemical determination using scanning electron microscopy (SEM), dynamic light scattering (DLS) and ultraviolet-visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR). Mesenchymal stem cells (MSCs) were used to evaluate the biocompatibility of this nanoparticle using the MTT assay and measuring reactive oxygen species (ROS) production. Also, the biological effects of the SDF-1α-conjugated nanoparticles (Au-Col-SDF1α) were assessed and the mechanisms were explored. Furthermore, we investigated the cell differentiation-inducing potential of these conjugated nanoparticles on MSCs toward endothelial cells, neurons, osteoblasts and adipocytes. We then ultimately explored the process of cell entry and transportation of the nanoparticles. Using a mouse animal model and retro-orbital sinus injection, we traced in vivo biodistribution to determine the biosafety of the Au-Col-SDF1α nanoparticles. In summary, our results indicate that Au-Col is a promising drug delivery system; it can be used to carry SDF1α to improve MSC therapeutic efficiency.

Direct and selective oxidation of benzene to phenol is a long-term goal in industry. Although great efforts have been made in homogenous catalysis, it still remains a huge challenge to drive this reaction via heterogeneous catalysts under mild conditions. Herein, a single-atom Au loaded MgAl-layered double hydroxide (Au1 -MgAl-LDH) with a well-defined structure, in which the Au single atoms are located on the top of Al3+ with Au-O4 coordination as revealed by extended x-ray-absorption fine-structure (EXAFS)and density-functional theory (DFT)calculation is reported. The photocatalytic results prove the Au1 -MgAl-LDH is capable of driving benzene oxidation reaction with O2 in water, and exhibits a high selectivity of 99% for phenol. While contrast experiment shows a ≈99% selectivity for aliphatic acid with Au nanoparticle loaded MgAl-LDH (Au-NP-MgAl-LDH). Detailed characterizations confirm that the origin of the selectivity difference can be attributed to the profound adsorption behavior of substrate benzene with Au single atoms and nanoparticles. For Au1 -MgAl-LDH, single Au-C bond is formed in benzene activation and result in the production of phenol. While for Au-NP-MgAl-LDH, multiple AuC bonds are generated in benzene activation, leading to the crack of CC bond.