Return connectedness and multiscale spillovers across clean energy indices and grain commodity markets around COVID-19 crisis.

The aim of this paper is to examine the return connectedness and multiscale spillovers between the Clean Energy Index and the grain commodity market around COVID-19. Using daily data from January 4, 2017 to July 1, 2022, a time-varying parametric vector autoregressive (TVP-VAR) connectedness approach is first used to reveal connectedness patterns before and during COVID-19. We further used Baruník and Křehlík (2018)'s frequency domain spillover method to assess connectedness in different domain horizons.

Wilforol A inhibits human glioma cell proliferation and deactivates the PI3K/AKT signaling pathway.

Objectives: To study the anti-proliferation activity of wilforol A against glioma cells and its possible molecular mechanisms.

Methods: Human glioma cell lines U118 MG and A172, human tracheal epithelial cells (TECs) and astrocytes (HAs) were exposed to various concentrations of wilforol A and evaluated for viability, apoptosis, and levels of proteins using WST-8 assay, flow cytometry and Western blot analysis, respectively.

Results: Wilforol A inhibited the growth of U118 MG and A172 cells, but not TECs and HAs, in a concentration-dependent manner and the estimated IC50 were 6 to 11 μM after 4 h-exposure.

Dependence and spillover among oil market, China's stock market and exchange rate: new evidence from the Vine-Copula-CoVaR and VAR-BEKK-GARCH frameworks.

We first employ the method of multivariate GARCH models and Vine-Copula-CoVaR to analyse relationships between dependence, systematic risk spillover, and volatility spillover between the USD/CNY exchange rate and the returns on WTI crude oil futures and the Chinese stock market since China's 2005 foreign exchange reform. We utilise daily data from 2005 to 2020. We find a more complex dependence of the USD/CNY exchange rate on stock markets and WTI crude oil prices.

Diamond coated artificial cardiovascular devices.

Ultrananocrystalline diamond (UNCD), an extremely smooth, low cost diamond coating was successfully developed herein for antithrombogenic application which requires high biocompatibility, low wear, low friction, and chemical inertness. The substrate materials utilized in the Jarvik 2000 ventricular assist device (VAD), silicon carbide and titanium alloy, provide an excellent substrate match for UNCD integration. The paper addresses the development of medical-quality UNCD films to significantly improve the knowledge base regarding the defect mechanisms of UNCD films, to reduce or eliminate known wear-inducing imperfections in the film, and to thoroughly characterize and test the films as well as assembled UNCD-coated VADs.

Ultrananocrystalline Diamond Integration with Pyrolytic Carbon Components of Mechanical Heart Valves.

In this report, an idea of integrating ultrananocrystalline diamond (UNCD) with pyrolytic carbon (PyC) -based mechanical heart valves, has been demonstrated. The report addresses the strategies to avoid graphitization and film delamination during the diamond coating. Raman and scratch tests showed that a UNCD film with high purity could adhere to the PyC substrate strongly.

The effect of electrode size and surface heterogeneity on electrochemical properties of ultrananocrystalline diamond microelectrode.

We report here the effect of electrode size on electrochemical properties of boron-doped ultrananocrystalline diamond (UNCD) microelectrodes using electrochemical impedance spectroscopy (EIS). By reducing microelectrode size from 250-μm to 10-μm diameter (), the shape of impedance spectra changes from linear line to two-arcs. The fitting of experimental data to electrochemical circuit model suggests that each arc likely corresponds to UNCD grains and grain boundary phases.

Polyetherimide-grafted Fe₃O₄@SiO2₂ nanoparticles as theranostic agents for simultaneous VEGF siRNA delivery and magnetic resonance cell imaging.

Engineering a safe and high-efficiency delivery system for efficient RNA interference is critical for successful gene therapy. In this study, we designed a novel nanocarrier system of polyethyleneimine (PEI)-modified Fe3O4@SiO2, which allows high efficient loading of VEGF small hairpin (sh)RNA to form Fe3O4@SiO2/PEI/VEGF shRNA nanocomposites for VEGF gene silencing as well as magnetic resonance (MR) imaging. The size, morphology, particle stability, magnetic properties, and gene-binding capacity and protection were determined.

Characterization of ultrananocrystalline diamond microsensors for dopamine detection.

We show the technical feasibility of coating and micro patterning boron-doped ultrananocrystalline diamond (UNCD) on metal microwires and of applying them as microsensors for the detection of dopamine using fast-scan cyclic voltammetry. UNCD electrode surface consistently generated electrochemical signals with high signal-to-noise ratio of >800 using potassium ferrocyanide-ferricyanide redox couple. Parylene patterned UNCD microelectrodes were effectively applied to detect dopamine reliably using flow injection analysis with a detection limit of 27 nM and in the striatum of the anesthetized rat during electrical stimulation of dopamine neurons.

A quantitative study of detection mechanism of a label-free impedance biosensor using ultrananocrystalline diamond microelectrode array.

It is well recognized that label-free biosensors are the only class of sensors that can rapidly detect antigens in real-time and provide remote environmental monitoring and point-of-care diagnosis that is low-cost, specific, and sensitive. Electrical impedance spectroscopy (EIS) based label-free biosensors have been used to detect a wide variety of antigens including bacteria, viruses, DNA, and proteins due to the simplicity of their detection technique. However, their commercial development has been hindered due to difficulty in interpreting the change in impedance upon antigen binding and poor signal reproducibility as a result of surface fouling and non-specific binding.

Control of Nanoscale Environment to Improve Stability of Immobilized Proteins on Diamond Surfaces.

Immunoassays for detection of bacterial pathogens rely on the selectivity and stability of bio-recognition elements such as antibodies tethered to sensor surfaces. The search for novel surfaces that improve the stability of biomolecules and assay performance has been pursued for a long time. However, the anticipated improvements in stability have not been realized in practice under physiological conditions because the surface functionalization layers on commonly used substrates, silica and gold, are themselves unstable on time scales of days.

[Effect of phosphor on accumulation and chemical forms of cadmium, and physiological characterization in different varieties of Capsicum annuum L].

Pot experiments were carried out to investigate the influence of different Phosphor (P) levels (0, 0.3% and 0.5%) on the plant growth, activities of antioxidant enzymes, accumulation and chemical forms of cadmium (Cd) in Capsicum annuum L.

Surface functionalization of thin-film diamond for highly stable and selective biological interfaces.

Carbon is an extremely versatile family of materials with a wide range of mechanical, optical, and mechanical properties, but many similarities in surface chemistry. As one of the most chemically stable materials known, carbon provides an outstanding platform for the development of highly tunable molecular and biomolecular interfaces. Photochemical grafting of alkenes has emerged as an attractive method for functionalizing surfaces of diamond, but many aspects of the surface chemistry and impact on biological recognition processes remain unexplored.

[Effect of different zinc levels on accumulation and chemical forms of cadmium, and physiological characterization in Capsicum annuum L].

Pot experiments were carried out to investigate the influence of different zinc (Zn) levels (0, 100, 200, 400 and 600 micromol x L(-1)) on the plant growth,activities of antioxidant enzymes, contents of chlorophyll a and b, accumulation and chemical forms of cadmium (Cd) in Capsicum annuum L. when exposed to Cd (20 mg x kg(-1)). The results showed that dry weights of leaf, stem, fruit and root, and contents of chlorophyll a and b in Capsicum annuum L.

Wear-resistant diamond nanoprobe tips with integrated silicon heater for tip-based nanomanufacturing.

We report exceptional nanoscale wear and fouling resistance of ultrananocrystalline diamond (UNCD) tips integrated with doped silicon atomic force microscope (AFM) cantilevers. The resistively heated probe can reach temperatures above 600 degrees C. The batch fabrication process produces UNCD tips with radii as small as 15 nm, with average radius 50 nm across the entire wafer.

Rapid thermal lysis of cells using silicon-diamond microcantilever heaters.

This paper presents the design and application of microcantilever heaters for biochemical applications. Thermal lysis of biological cells was demonstrated as a specific example. The microcantilever heaters, fabricated from selectively doped single crystal silicon, provide local resistive heating with highly uniform temperature distribution across the cantilevers.

Nanofabrication in cellulose acetate.

We have demonstrated nanofabrication with commercialized cellulose acetate. Cellulose acetate is used for bulk nanofabrication and surface nanofabrication. In bulk nanofabrication, cellulose acetate reacts with an e-beam and permanent patterns are formed in it instead of being transferred to other substrates.

Micro/nanosized refractive lens arrays formed by means of conformal thin film deposition.

We provide a 'growing' method for fabricating a microlens array with lateral size of a few microns or less. Instead of using complicated etching techniques, the method forms a spherical profile of the lens using conformal chemical vapor deposition. We have fabricated two lens arrays.