Evaluation of the effect of nitrate and chloride on Cd(II)-induced cell oxidative stress by scanning electrochemical microscopy.

Cadmium (Cd) is one of the most prevalent toxic metal pollutants, which is widely distributed in various environmental media and organisms. Literature studies have documented that Cd could stimulate cellular oxidative stress, and the increased intracellular reactive oxygen species (ROS) might destroy certain proteins and DNA and subsequently lead to cell apoptosis. Although several studies have studied the co-exposure between cadmium and other metals, information on the potential effects of Cd and its counterions is still lacking.

Anionic N Macrocycles and a Polynitrogen Double Helix in Novel Yttrium Polynitrides YN and Y N at 100 GPa.

Two novel yttrium nitrides, YN and Y N , were synthesized by direct reaction between yttrium and nitrogen at 100 GPa and 3000 K in a laser-heated diamond anvil cell. High-pressure synchrotron single-crystal X-ray diffraction revealed that the crystal structures of YN and Y N feature a unique organization of nitrogen atoms-a previously unknown anionic N macrocycle and a polynitrogen double helix, respectively. Density functional theory calculations, confirming the dynamical stability of the YN and Y N compounds, show an anion-driven metallicity, explaining the unusual bond orders in the polynitrogen units.

Metagenomics illuminated the mechanism of enhanced nitrogen removal and vivianite recovery induced by zero-valent iron in partial-denitrification/anammox process.

In this study, a novel strategy of zero-valent iron (ZVI) combined with acetic acid was proposed to optimize partial-denitrification/anammox (PD/A) process, and enhanced nitrogen removal mechanism was elucidated through metagenomics. Results showed that the optimal nitrogen and phosphorus removal were as high as 99.50% and 98.

Repeated Exposure of Macrophages to Synthetic Amorphous Silica Induces Adaptive Proteome Changes and a Moderate Cell Activation.

Synthetic amorphous silica (SAS) is a nanomaterial used in a wide variety of applications, including the use as a food additive. Two types of SAS are commonly employed as a powder additive, precipitated silica and fumed silica. Numerous studies have investigated the effects of synthetic amorphous silica on mammalian cells.

The response of metal mobilization and redistribution to reoxygenation in Baltic Sea anoxic sediments.

To bring life back to anoxic coastal and sea basins, reoxygenation of anoxic/hypoxic zones has been proposed. This research focuses on the metals released during the oxidization of sediments from two locations in the anoxic Eastern Gotland Basin under a laboratory-scale study. Triplicate experimental cores and reference cores were collected from the North and South Eastern Gotland Basins.

Bidirectional Hydrogen Electrocatalysis on Epitaxial Graphene.

The climate change due to human activities stimulates the research on new energy resources. Hydrogen has attracted interest as a green carrier of high energy density. The sustainable production of hydrogen is achievable only by water electrolysis based on the hydrogen evolution reaction (HER).

Substrate-Modulated Synthesis of Metal-Organic Hybrids by Tunable Multiple Aryl-Metal Bonds.

Assembly of semiconducting organic molecules with multiple aryl-metal covalent bonds into stable one- and two-dimensional (1D and 2D) metal-organic frameworks represents a promising route to the integration of single-molecule electronics in terms of structural robustness and charge transport efficiency. Although various metastable organometallic frameworks have been constructed by the extensive use of single aryl-metal bonds, it remains a great challenge to embed multiple aryl-metal bonds into these structures due to inadequate knowledge of harnessing such complex bonding motifs. Here, we demonstrate the substrate-modulated synthesis of 1D and 2D metal-organic hybrids (MOHs) with the organic building blocks (perylene) interlinked solely with multiple aryl-metal bonds via the stepwise thermal dehalogenation of 3,4,9,10-tetrabromo-1,6,7,12-tetrachloroperylene and subsequent metal-organic connection on metal surfaces.

Transition Metal Carbo-Chalcogenide "TMCC:" A New Family of 2D Materials.

Here, a new family of 2D transition metal carbo-chalcogenides (TMCCs) is reported, which can be considered a combination of two well-known families, TM carbides (MXenes) and TM dichalcogenides (TMDCs), at the atomic level. Single sheets are successfully obtained from multilayered Nb S C and Ta S C using electrochemical lithiation followed by sonication in water. The parent multilayered TMCCs are synthesized using a simple, scalable solid-state synthesis followed by a topochemical reaction.

Inhibitory effects of zinc chloride (ZnCl), n-acetyl-L-cysteine (NAC), and calcium/calmodulin dependent protein kinase II inhibitor (KN93) on Cd-induced abnormal cell morphology and membrane permeability.

Cadmium (Cd) could reduce abnormal cell morphology and membrane permeability, however, there are few studies on the detoxification of Cd-reduced cell membrane toxicity. In the present study, we firstly studied the effects of zinc chloride (ZnCl), n-acetyl-L-cysteine (NAC), and calcium/calmodulin dependent protein kinase II inhibitor (KN93) on cell membrane permeability, respectively; then, we studied the inhibitory effects of ZnCl, NAC, and KN93 on Cd-induced abnormal cell membrane permeability by scanning electrochemical microscopy (SECM) scanning imaging, transverse scanning curve and DPV technology. Our results showed that 10 μmol·L ZnCl, 0.

Vanadium-catalyzed Oxidative Conversion of Primary Aromatic Alcohols into Amides and Nitriles with Molecular Oxygen.

Amides or nitriles are important building blocks because of the widespread occurrence in chemistry and biology. The development of green and efficient catalytic approaches to introduce nitrogen functionality is highly desired. Herein, a vanadium-based material V-N-C-700 was prepared via a simple and convenient method and employed for liquid-phase catalytic ammoxidation of alcohols with molecular oxygen.

Microscopic Insights into Cation-Coupled Electron Hopping Transport in a Metal-Organic Framework.

Electron transport through metal-organic frameworks by a hopping mechanism between discrete redox active sites is coupled to diffusion-migration of charge-balancing counter cations. Experimentally determined apparent diffusion coefficients, , that characterize this form of charge transport thus contain contributions from both processes. While this is well established for MOFs, microscopic descriptions of this process are largely lacking.

Termination-Accelerated Electrochemical Nitrogen Fixation on Single-Atom Catalysts Supported by MXenes.

The synthesis of ammonia (NH) from nitrogen (N) under ambient conditions is of great significance but hindered by the lack of highly efficient catalysts. By performing first-principles calculations, we have investigated the feasibility for employing a transition metal (TM) atom, supported on TiCT MXene with O/OH terminations, as a single-atom catalyst (SAC) for electrochemical nitrogen reduction. The potential catalytic performance of TM single atoms is evaluated by their adsorption behavior on the MXene, together with their ability to bind N and to desorb NH molecules.

Low-cost and rapid prototyping of integrated electrochemical microfluidic platforms using consumer-grade off-the-shelf tools and materials.

We present a low-cost, accessible, and rapid fabrication process for electrochemical microfluidic sensors. This work leverages the accessibility of consumer-grade electronic craft cutters as the primary tool for patterning of sensor electrodes and microfluidic circuits, while commodity materials such as gold leaf, silver ink pen, double-sided tape, plastic transparency films, and fabric adhesives are used as its base structural materials. The device consists of three layers, the silver reference electrode layer at the top, the PET fluidic circuits in the middle and the gold sensing electrodes at the bottom.

Invertebrate Species for the Bioavailability and Accumulation Assessment of Manufactured Polymer-Based Nano- and Microplastics.

Bioaccumulation tests with invertebrates have recently been discussed as a suitable alternative to bioaccumulation tests with metal- or metal oxide-based nanoparticles in fish for regulatory assessment. In the present study, as a first step, we investigated the suitability of three invertebrate species for bioaccumulation tests with nano- and microplastics. In a laboratory approach the freshwater bivalve Corbicula fluminea, the freshwater amphipod Hyalella azteca, and the terrestrial isopod Porcellio scaber were exposed to fluorescently labeled nano- and microplastics to evaluate their suitability to estimate the bioavailability and bioaccumulation of these test items.

Chemoselective Transamidation of Thioamides by Transition-Metal-Free N-C(S) Transacylation.

Thioamides represent highly valuable isosteric in the strictest sense "single-atom substitution" analogues of amides that have found broad applications in chemistry and biology. A long-standing challenge is the direct transamidation of thioamides, a process which would convert one thioamide bond (R-C(S)-NR R ) into another (R-C(S)-NR N ). Herein, we report the first general method for the direct transamidation of thioamides by highly chemoselective N-C(S) transacylation.

Biochemical Characterization of Two Rhamnogalacturonan Lyases From ATCC 8483 With Preference for RG-I Substrates.

Rhamnogalacturonan lyase (RGL) cleaves backbone α-1,4 glycosidic bonds between L-rhamnose and D-galacturonic acid residues in type I rhamnogalacturonan (RG-I) by β-elimination to generate RG oligosaccharides with various degrees of polymerization. Here, we cloned, expressed, purified and biochemically characterized two RGLs (Bo3128 and Bo4416) in the PL11 family from ATCC 8483. Bo3128 and Bo4416 displayed maximal activity at pH 9.

Niche differentiation of sulfur-oxidizing bacteria (SUP05) in submarine hydrothermal plumes.

Hydrothermal plumes transport reduced chemical species and metals into the open ocean. Despite their considerable spatial scale and impact on biogeochemical cycles, niche differentiation of abundant microbial clades is poorly understood. Here, we analyzed the microbial ecology of two bathy- (Brothers volcano; BrV-cone and northwest caldera; NWC) and a mesopelagic (Macauley volcano; McV) plumes on the Kermadec intra-oceanic arc in the South Pacific Ocean.

Simulations of x-ray absorption spectra for CO desorbing from Ru(0001) with transition-potential and time-dependent density functional theory approaches.

The desorption of a carbon monoxide molecule from a Ru(0001) surface was studied by means of X-ray Absorption Spectra (XAS) computed with Transition Potential (TP-DFT) and Time Dependent (TD-DFT) DFT methods. By unraveling the evolution of the CO electronic structure upon desorption, we observed that at 2.3 Å from the surface, the CO molecule has already predominantly gas-phase character.

Electrical Tuning of Plasmonic Conducting Polymer Nanoantennas.

Nanostructures of conventional metals offer manipulation of light at the nanoscale but are largely limited to static behavior due to fixed material properties. To develop the next frontier of dynamic nano-optics and metasurfaces, this study utilizes the redox-tunable optical properties of conducting polymers, as recently shown to be capable of sustaining plasmons in their most conducting oxidized state. Electrically tunable conducting polymer nano-optical antennas are presented, using nanodisks of poly(3,4-ethylenedioxythiophene:sulfate) (PEDOT:Sulf) as a model system.

Evaluation of the Antiviral Activity against Infectious Pancreatic Necrosis Virus (IPNV) of a Copper (I) Homoleptic Complex with a Coumarin as Ligand.

The aquatic infectious pancreatic necrosis virus (IPNV) causes a severe disease in farmed salmonid fish that generates great economic losses in the aquaculture industry. In the search for new tools to control the disease, in this paper we show the results obtained from the evaluation of the antiviral effect of [Cu(NN)](ClO) Cu(I) complex, synthesized in our laboratory, where the NN ligand is a synthetic derivate of the natural compound coumarin. This complex demonstrated antiviral activity against IPNV at 5.

Fullerene binding effects in Al(III)/Zn(II) Porphyrin/Phthalocyanine photophysical properties and charge transport.

We evaluate the fullerene C binding effect; through the metal (Al) and through the ligand (Pc,TPP), on the photophysical and charge transport properties of M-porphyrin(TPP)/phthalocyanine(Pc) (M = Al(III), Zn(II)). We perform density functional theory (DFT) and time-dependent DFT calculations for the macrocycle-C dyads, showing that all systems studied are thermodynamically favorable. The C binding effect on the absorption spectrum is a red-shift of the Q and Soret (B) bands of TPPs and Pcs.

A Novel 3D Hierarchical Plasmonic Functional Cu@CoO@Ag Array as Intelligent SERS Sensing Platform with Trace Droplet Rapid Detection Ability for Pesticide Residue Detection on Fruits and Vegetables.

Rapid and effective detection of pesticide residues from complex surfaces of fruits and vegetables has important significance. Herein, we report a novel three-dimensional (3D) hierarchical porous functional surface-enhanced Raman scattering (SERS) substrate, which is fabricated by successive two-step hydrothermal synthesis strategy of silver nanoparticles (Ag NPs) and cobalt oxide nanowires (CoO NWs) on the 3D copper foam framework as Cu@CoO@Ag-H. The strategy offers a new avenue for localized plasmonic materials distribution and construction, which exhibits better morphology regulation ability and SERS activity (or hotspots engineering) than physical spurring obtained Cu@CoO@Ag-S.

Effects of x-ray free-electron laser pulse intensity on the Mn K x-ray emission spectrum in photosystem II-A case study for metalloprotein crystals and solutions.

In the last ten years, x-ray free-electron lasers (XFELs) have been successfully employed to characterize metalloproteins at room temperature using various techniques including x-ray diffraction, scattering, and spectroscopy. The approach has been to outrun the radiation damage by using femtosecond (fs) x-ray pulses. An example of an important and damage sensitive active metal center is the MnCaO cluster in photosystem II (PS II), the catalytic site of photosynthetic water oxidation.