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Summary: Background: Stroke and dementia are the leading causes of neurological disease burden. Detrimental effects of air pollution on both conditions are increasingly recognised, while the impacts on the dynamic transitions have not yet been explored, and whether critical time intervals exist is unknown. Methods: This prospective study was conducted based on the UK Biobank. Annual average air pollution concentrations at baseline year 2010 estimated by land-use regression models were used as a proxy for long-term air pollution exposure. Associations between multiple air pollutants (PM2.5, PM2.5-10, and NO2) indicated by air pollution score and the dynamic transitions of stroke and dementia were estimated, and the impacts during critical time intervals were explored. The date cutoff of this study was February 29, 2020. Findings: During a median follow-up of 10.9 years in 413,372 participants, 6484, 3813, and 376 participants developed incident stroke, dementia, and comorbidity of stroke and dementia. For the overall transition from stroke to comorbid dementia, the hazard ratio (HR) for each interquartile range (IQR) increase in air pollution score was 1.38 (95% CI, 1.15, 1.65), and the risks were limited to two time intervals (within 1 year and over 5 years after stroke). As for the transition from dementia to comorbid stroke, increased risk was only observed during 2–3 years after dementia. Interpretation: Our findings suggested that air pollution played an important role in the dynamic transition of stroke and dementia even at concentrations below the current criteria. The findings provided new evidence for alleviating the disease burden of neurological disorders related to air pollution during critical time intervals. Funding: The State Scholarship Fund of China Scholarship Council.

Changes in Polycomb repression during interphase transition modulate the ability of pluripotent cells to enter cell differentiation.

Objectives: Recent studies have linked exposure to road traffic noise or air pollution with incident type 2 diabetes (T2D), but investigation on their co-exposure was limited and underlying mechanisms remain unclear. We hypothesized that long-term co-exposure to road traffic noise and air pollution increases the risk of incident T2D via the development of metabolic syndrome (MetS). Methods: This prospective study included 390,834 participants in UK Biobank. Cumulative risk index (CRI), the health-based weighted levels of multiple exposures, was applied to characterize the co-exposure to 24-hour road traffic noise (Lden), particulate matter with aerodynamic diameter ≤ 2.5 µm (PM2.5), and nitrogen dioxide (NO2). Lden was modeled by the Common Noise Assessment Methods in Europe and air pollutant levels were measured by the Land Use Regression model at participants’ residential addresses. Incident T2D was ascertained through linkages to inpatient hospital records. MetS was defined by five (central obesity, triglycerides, HDL cholesterol, glucose, and blood pressure) or six factors (C-reactive protein additionally). Cox proportional hazard models were used to assess the association between environmental exposures and incident T2D, and mediation analyses were applied to investigate the role of MetS. Results: After a median of 10.9 years of follow-up, 13,214 (3.4%) incident T2D cases were ascertained. The exposure to Lden, PM2.5, and NO2, as well as their co-exposure, were significantly associated with an elevated risk of incident T2D, with HRs of 1.03 (95%CI: 1.00, 1.05) per 3.5 dB(A) increase in Lden, 1.05 (95%CI: 1.01, 1.10) per 1.3 μg/m3 increase in PM2.5, 1.07 (95%CI: 1.02, 1.11) per 9.8 μg/m3 increase in NO2, and 1.06 (95%CI: 1.02, 1.09) per interquartile range increase in CRI. MetS significantly mediated 43.5%− 54.7% of the CRI-T2D relationship. Conclusions: Long-term co-exposure to road traffic noise and air pollution is associated with an elevated risk of incident T2D, which may partly be mediated by MetS.

In order to clarify the effect of Fe-based amorphous alloy on the separation mechanism and corrosion behavior of Cu-based immiscible coatings, 10 wt% Fe-based amorphous powder was designed into 90 wt% pure Cu powder to produce the amorphous alloy reinforced Cu-based immiscible coatings by laser melting deposition. The self-organized microstructure and corrosion behavior of immiscible coatings with different laser energy densities were investigated. When the different laser energy densities are adopted, many carbides (M23C6 and M12C) are dispersed in the lower α-Fe layer and large amounts of α-Fe particles containing carbides are embedded in the upper ε-Cu layer due to liquid phase separation. With increasing laser energy density (LED), the α-Fe dendrites are coarser and the area of carbides decrease. The interface of coating and substrate experiences a transition from “poor bonding (gaps) to “good bonding” and “crack debonding”. Moreover, the corrosion characteristics of immiscible coatings also experience a transformation from “crevice corrosion” to “enhanced protection of passive films” and “reduced protection of passive films”. As a result, the corrosion resistance increases first then decreases and the immiscible coating deposited by the LED of 31.25 J/mm2 exhibits the highest corrosion resistance.

Oxidative stress plays a key role in the progress of acute lung injury (ALI), which is an acute, progressive respiratory failure characterized by alveolar capillary injury caused by various external and internal factors other than cardiogenic factors. Pulmonary vascular endothelial cells are the main target cells during ALI, and therefore the mitochondrial targeting antioxidant derivative triphenylphosphine-melatonin (TPP-MLT) was encapsulated in VCAM-1 antibodies-conjugated nanostructured lipid carriers (VCAM@TPP-MLT NLCs) for lung targeting delivery. VCAM@TPP-MLT NLCs could be preferentially internalized by inflammatory endothelial cells in lung tissues, and then the released TPP-MLT from NLCs effectively eliminated the excessive reactive oxide species (ROS) and ameliorated cell apoptosis. Overall, the results suggested that VCAM@TPP-MLT NLCs exhibited remarkable in vitro and in vivo therapeutic effect on ALI, and could be a promising and efficient strategy for the treatment of ALI.

Plain language summary Gestational diabetes mellitus (GDM) is a common pregnancy complication affecting up to 1 in 6 pregnant women worldwide. Whilst the condition usually resolves soon after delivery, women are at high risk of developing type 2 diabetes mellitus (T2DM). In this study, we asked women living in Chengdu, a city in western China, about what they knew about their risk of diabetes and how they felt about participating in interventions after birth to prevent T2DM. After listening to the views of 20 women, we concluded that in this setting most women are happy to attend T2DM screening programs after birth, and would be willing to consider participating in interventions and research after birth to prevent T2DM. The interventions most preferred were those that aimed at lifestyle changes, and many women said would like to receive this information through their smartphone, for example through an app or social media channel. Women were reluctant to take medications to prevent T2DM. The main factors that influenced how women felt towards interventions to prevent T2DM were: (1) their experiences with the health system during pregnancy; (2) whether the home environment was supportive to make changes to diet and lifestyle; (3) any experiences of T2DM in family members; (4) their knowledge of diabetes and perception of risk; (5) concerns about personal and baby health; (6) feelings and emotions in the postnatal period, and (7) lifestyle constraints making it difficult to make dietary changes.

Programmable mechanochromic systems hold important roles in designing advanced bionic robots and colorimetric devices. Herein, the authors report the development of magnetic-plasmonic hybrid nanorods that can be integrated into thin polymer films with controlled orientations to display programmable mechanochromism.

The metal-halide ionic octahedron is the optoelectronic unit for halide perovskites, and a crown ether–assisted supramolecular assembly approach can pack various ionic octahedra into tunable symmetries. In this work, we demonstrate near-unity photoluminescence quantum yield (PLQY) blue and green emission with the supramolecular assembly of hafnium (Hf) and zirconium (Zr) halide octahedral clusters. (18C6@K)2HfBr6 powders showed blue emission with a near-unity PLQY (96.2%), and green emission was also achieved with (18C6@K)2ZrCl4Br2 powders at a PLQY of 82.7%. These highly emissive powders feature facile low-temperature solution-based synthesis conditions and maintain high PLQY in solution-processable semiconductor inks under ambient conditions, and they were used in thin-film displays and emissive three-dimensional–printed architectures that exhibited high spatial resolution. [ABSTRACT FROM AUTHOR]

Phase transitions in halide perovskites triggered by external stimuli generate significantly different material properties, providing a great opportunity for broad applications. Here, we demonstrate an In-based, charge-ordered (In+/In3+) inorganic halide perovskite with the composition of Cs2In(I)In(III)Cl6 in which a pressure-driven semiconductor-to-metal phase transition exists. The single crystals, synthesized via a solid-state reaction method, crystallize in a distorted perovskite structure with space group I4/m with a = 17.2604(12) Ã…, c = 11.0113(16) Ã… if both the strong reflections and superstructures are considered. The supercell was further confirmed by rotation electron diffraction measurement. The pressure-induced semiconductor-to-metal phase transition was demonstrated by high-pressure Raman and absorbance spectroscopies and was consistent with theoretical modeling. This type of charge-ordered inorganic halide perovskite with a pressure-induced semiconductor-to-metal phase transition may inspire a range of potential applications. [ABSTRACT FROM AUTHOR]

A numerical method for the analysis of the fields in highly oversized waveguides is proposed in this paper. This method allows the simulation of the fields on waveguide walls with arbitrary surface deformations in the case that the waveguide is highly oversized, and the wall deformations are shallow and smooth. Combined with the analysis method, an algorithm has been developed for synthesizing the waveguide wall to provide a desired field distribution. As an example, a 309.6-mm-long wave- guide launcher has been designed for a 170-GHz coaxial-cavity gyrotron to transform the TE34,19 cavity mode to a fundamental Gaussian distribution. An efficiency of transformation to the desired fundamental Gaussian mode of 96.3% has been obtained at the launcher aperture, whereas the transformation efficiency is just 86% using a conventional dimpled-wall launcher with a length of 660 mm. [ABSTRACT FROM AUTHOR]

This paper presents the investigation of a mirror system of a quasi-optical (QO) mode converter for a high-power coaxial-cavity gyrotron. The mirror system consists of three mirrors. The first mirror is a quasi-elliptical one. Based on the Katsenelenbaum-Semenov Algorithm (KSA), the second and the third mirrors are iteratively optimized as adapted phase-correcting mirrors to transform the outgoing wave beam into a fundamental Gaussian structure. The investigation shows that the focal length of the quasi-elliptical mirror has a great influence on the optimized conversion efficiency, and, hence, it should be chosen to match the asymptotic beam growth (ABG) angle well in order to obtain high conversion efficiency. The design of a mirror system has been performed for a 2 MW, continuous wave (CW), 170 GHz, and TE34,19-mode coaxial-cavity gyrotron, which is under development at Forschungszentrum Karlsruhe, Germany. Taking into account the size of the mirrors and the conversion efficiency, a mirror system has been designed with a conversion efficiency of 98.3%. [ABSTRACT FROM AUTHOR]

This paper investigates the antenna waveguide (launcher), the main component of the quasi-optical mode converter of a 2-MW 170-GHz TE34,19 coaxial cavity gyrotron, which is under development within the European Union. For coaxial gyrotrons operating in very high-order cavity modes like the TE34,19, due to the ratio of the caustic to cavity radius of 0.323, the transformation of the high-order cavity mode into a nearly Gaussian distribution cannot be done as good as for gyrotron modes where the ratio of caustic to cavity radius is approximately 0.5. The simulation results for the TE34,19 mode show that the average and peak values of the power density at the edges of the cuts of a conventional dimpled-wall launcher are approximately 32.3 W/cm² and 63.8, respectively, which will produce diffraction losses and reflection of power from the cuts. This paper reports on an advanced launcher for which average and peak values of power density of 1.9 and 5.4 W/cm² at the edges of the cuts are achieved, and a well-focused field at the aperture with a scalar Gaussian mode content of 94.8 % is obtained. [ABSTRACT FROM AUTHOR]

As the social public resources,the value and function of government data has become a global consensus,but the construction of our local open government data platforms is still in a preliminary stage.Taking the Guiyang open government data platform as an example,the design and construction scheme of open government data platform was introduced from various modes,general framework,potential data acquisition mode,data quality management and metadata construction.The meaningful reference for the construction of our local open government data platform was provided.

Gyrotron R&D within the EUROfusion Work Package Heating and Current Drive (WPHCD) is addressing the challenging requirements posed on gyrotrons by the European concept for a demonstration fusion power plant (EU DEMO). These requirements, as specified within WPHCD, ask for highly reliable and robust long-pulse operation of the gyrotron, delivering 2 MW of microwave power at frequencies above 200 GHz with a high overall efficiency above 60% and the option for fast frequency step-tunability. To meet these targets, which are clearly beyond today’s state-of-the-art, the R&D activities within WPHCD are organized in five main branches: these are the experimental verification of the advanced coaxial gyrotron technology at long pulses, the development of a coaxial gyrotron meeting the EU DEMO requirements, the development of multi-stage depressed collectors for enhanced energy recovery, the development of large broadband diamond windows to allow fast frequency tunability of the gyrotron, and the studies on further innovations and improvement of critical gyrotron components, in view of optimization of performance, reliability, and industrialization. The paper presents the progress made on these activities, the recent results, and the near-term planning. The major recent achievements include (i) the experimental validation of the fabrication of the new, water-cooled components for the longer-pulse coaxial gyrotron at Karlsruhe Institute of Technology, by demonstrating 2.2 MW at 170 GHz with 33% efficiency without depressed collector, (ii) the design of key components for a 2 MW, 170/204 GHz dual-frequency coaxial gyrotron, (iii) the design of a two-stage depressed collector with 77% efficiency, (iv) the first-ever production, in an industrial plasma reactor, of large chemical vapor deposition diamond wafers of 180 mm diameter, (v) the procurement of an advanced electron gun with coated emitter edges, and (vi) advances in the theoretical and numerical modelling for investigating improved concepts for the gyrotron beam tunnel and cavity. [ABSTRACT FROM AUTHOR]

High-power, high-frequency gyrotrons for electron cyclotron resonance heating and current drive, such as proposed for the demonstration thermonuclear fusion reactor DEMO, require operating modes of very high order. As it is shown, the selection of the operating modes for such gyrotrons can be based on multi-frequency operability. A general selection strategy is derived, suitable for multi-purpose multi-frequency gyrotrons with quasi-optical mode converter and single-disc output window. Two examples, one of them relevant for future DEMO gyrotron designs, are discussed. [ABSTRACT FROM AUTHOR]

Ferroelectric semiconductors are rare materials with both spontaneous polarizations and visible light absorptions that are promising for designing functional photoferroelectrics, such as optical switches and ferroelectric photovoltaics. The emerging halide perovskites with remarkable semiconducting properties also have the potential of being ferroelectric, yet the evidence of robust ferroelectricity in the typical three-dimensional hybrid halide perovskites has been elusive. Here, we report on the investigation of ferroelectricity in all-inorganic halide perovskites, CsGeX3, with bandgaps of 1.6 to 3.3 eV. Their ferroelectricity originates from the lone pair stereochemical activity in Ge (II) that promotes the ion displacement. This gives rise to their spontaneous polarizations of ~10 to 20 C/cm2, evidenced by both ab initio calculations and key experiments including atomic-level ionic displacement vector mapping and ferroelectric hysteresis loop measurement. Furthermore, characteristic ferroelectric domain patterns on the well-defined CsGeBr3 nanoplates are imaged with both piezo-response force microscopy and nonlinear optical microscopic method. [ABSTRACT FROM AUTHOR]

The article offers information on successful synthesis of a series of blue-emissive two-dimensional Ruddlesden-Popper phase single crystals and their high–color purity blue-emitting LED demonstrations. Topics include a series of bandgap emissions based on the different layer thicknesses; and the elucidation of temperature-induced device degradation by investigation of crystal structural and spectral evolution dynamics via in situ temperature-dependent single-crystal x-ray diffraction.