Current Status of Indole-Derived Marine Natural Products: Synthetic Approaches and Therapeutic Applications.

Indole is a versatile pharmacophore widely distributed in bioactive natural products. This privileged scaffold has been found in a variety of molecules isolated from marine organisms such as algae and sponges. Among these, indole alkaloids represent one of the biggest, most promising family of compounds, having shown a wide range of pharmacological properties including anti-inflammatory, antiviral, and anticancer activities.

Quantum interference enhances the performance of single-molecule transistors.

Quantum effects in nanoscale electronic devices promise to lead to new types of functionality not achievable using classical electronic components. However, quantum behaviour also presents an unresolved challenge facing electronics at the few-nanometre scale: resistive channels start leaking owing to quantum tunnelling. This affects the performance of nanoscale transistors, with direct source-drain tunnelling degrading switching ratios and subthreshold swings, and ultimately limiting operating frequency due to increased static power dissipation.

Modes of the Dark Ages 21 cm field accessible to a lunar radio interferometer.

At redshifts beyond [Formula: see text], the 21 cm line from neutral hydrogen is expected to be essentially the only viable probe of the three-dimensional matter distribution. The lunar far-side is an extremely appealing site for future radio arrays that target this signal, as it is protected from terrestrial radio frequency interference, and has no ionosphere to attenuate and absorb radio emission at low frequencies (tens of MHz and below). We forecast the sensitivity of low-frequency lunar radio arrays to the bispectrum of the 21 cm brightness temperature field, which can in turn be used to probe primordial non-Gaussianity generated by particular early universe models.

Engineering Domain Variants in 0.7Pb(MgNb)-0.3PbTiO Single Crystals Using High-Frequency AC Poling.

Single crystals of (001)-oriented 0.7Pb(MgNb)-0.3PbTiO (PMN-30PT) with a composition near the morphotropic phase boundary have attracted considerable attention due to their superior dielectric and electromechanical performance.

Plastics in the environment in the context of UV radiation, climate change and the Montreal Protocol: UNEP Environmental Effects Assessment Panel, Update 2023.

This Assessment Update by the Environmental Effects Assessment Panel (EEAP) of the United Nations Environment Programme (UNEP) considers the interactive effects of solar UV radiation, global warming, and other weathering factors on plastics. The Assessment illustrates the significance of solar UV radiation in decreasing the durability of plastic materials, degradation of plastic debris, formation of micro- and nanoplastic particles and accompanying leaching of potential toxic compounds. Micro- and nanoplastics have been found in all ecosystems, the atmosphere, and in humans.

Liquid metals for boosting stability of zeolite catalysts in the conversion of methanol to hydrocarbons.

Methanol-to-hydrocarbons (MTH) process has been considered one of the most practical approaches for producing value-added products from methanol. However, the commonly used zeolite catalysts suffer from rapid deactivation due to coke deposition and require regular regeneration treatments. We demonstrate that low-melting-point metals, such as Ga, can effectively promote more stable methanol conversion in the MTH process by slowing coke deposition and facilitating the desorption of carbonaceous species from the zeolite.

Not All Binding Sites Are Equal: Site Determination and Folding State Analysis of Gas-Phase Protein-Metallodrug Adducts.

Modern approaches in metallodrug research focus on compounds that bind protein targets rather than DNA. However, the identification of protein targets and binding sites is challenging. Using intact mass spectrometry and proteomics, we investigated the binding of the antimetastatic agent RAPTA-C to the model proteins ubiquitin, cytochrome c, lysozyme, and myoglobin.

Radiometric survey of sediments and health risk assessments from the southern coastal area of Delta State, Nigeria.

Over the years, the release of potential radiological components around the oil exploration environment has increased with potential health implications.Yet; the mechanism and health associated assessment have remained fuzzy to most experimental scientists. The current study determines the activity concentration of radionuclides in sediments and the corresponding health risk assessments from the hydrocarbon exploration environment of the southern coastal area of Delta State, Nigeria.

How heat propagates in liquid He.

In Landau's Fermi liquid picture, transport is governed by scattering between quasi-particles. The normal liquid He conforms to this picture but only at very low temperature. Here, we show that the deviation from the standard behavior is concomitant with the fermion-fermion scattering time falling below the Planckian time, and the thermal diffusivity of this quantum liquid is bounded by a minimum set by fundamental physical constants and observed in classical liquids.

Connections to the Electrodes Control the Transport Mechanism in Single-Molecule Transistors.

When designing a molecular electronic device for a specific function, it is necessary to control whether the charge-transport mechanism is phase-coherent transmission or particle-like hopping. Here we report a systematic study of charge transport through single zinc-porphyrin molecules embedded in graphene nanogaps to form transistors, and show that the transport mechanism depends on the chemistry of the molecule-electrode interfaces. We show that van der Waals interactions between molecular anchoring groups and graphene yield transport characteristic of Coulomb blockade with incoherent sequential hopping, whereas covalent molecule-electrode amide bonds give intermediately or strongly coupled single-molecule devices that display coherent transmission.

Electronic origin of negative thermal expansion in samarium hexaboride revealed by X-ray diffraction and total scattering.

Samarium hexaboride, SmB, is a negative thermal expansion (NTE) material whose structure is similar to other known NTE materials such as the family of Prussian blues. In the Prussian blues, NTE is due to a phonon mechanism, but we recently showed from DFT calculations that this is unlikely in SmB (Li , . 2023, , 10749).

Application of coal fly ash based ceramic membranes in wastewater treatment: A sustainable alternative to commercial materials.

The continued increase in the global population has resulted in increased water demand for domestic, agricultural, and industrial purposes. These activities have led to the generation of high volumes of wastewater, which has an impact on water quality. Consequently, more practical solutions are needed to improve the current wastewater treatment systems.

Fabrication of Potassium- and Rubidium-Doped Formamidinium Lead Bromide Nanocrystals for Surface Defect Passivation and Improved Photoluminescence Stability.

The past decade has seen a rapid development in metal halide perovskite nanocrystals (NCs), which has been witnessed by their potential applications in nanotechnology. The inimitable chemical nature behind their unique photoluminescence characteristics has attracted a growing body of researchers. However, the low intrinsic stability and surface defects of perovskite NCs have hampered their widespread applications.

Crystal Engineering of a New Hexafluorogermanate Pillared Hybrid Ultramicroporous Material Delivers Enhanced Acetylene Selectivity.

Hybrid ultramicroporous materials (HUMs), metal-organic platforms that incorporate inorganic pillars, are a promising class of porous solids. A key area of interest for such materials is gas separation, where HUMs have already established benchmark performances. Thanks to their ready compositional modularity, we report the design and synthesis of a new HUM, , incorporating the ligand (4-(3,5-dimethyl-1-pyrazol-4-yl)pyridine, ) and GeF pillaring anions.

Chemical elements in Elaeis guineensis materials and derived oil.

The production of oil palm (Elaeis guineensis) in Southeast Asia is vital to the economies of Indonesia and Malaysia. Both fertilisers and pesticides used in palm production can contain elevated concentrations of Trace Elements (TEs) which may accumulate in soils and leaf tissues of plants. We hypothesised that leaves from oil palms may be deficient in essential elements, while containing elevated concentrations of non-essential TEs commonly found in agrichemicals.

Structure-Property Relationships for the Electronic Applications of Bis-Adduct Isomers of Phenyl-C Butyric Acid Methyl Ester.

Higher adducts of a fullerene, such as the bis-adduct of PCBM (bis-PCBM), can be used to achieve shallower molecular orbital energy levels than, for example, PCBM or C Substituting the bis-adduct for the parent fullerene is useful to increase the open-circuit voltage of organic solar cells or achieve better energy alignment as electron transport layers in, for example, perovskite solar cells. However, bis-PCBM is usually synthesized as a mixture of structural isomers, which can lead to both energetic and morphological disorder, negatively affecting device performance. Here, we present a comprehensive study on the molecular properties of 19 pure bis-isomers of PCBM using a variety of characterization methods, including ultraviolet photoelectron spectroscopy, thermal gravimetric analysis, differential scanning calorimetry, single crystal structure, and (time-dependent) density functional theory calculation.

Magnetocapacitance at the Ni/BiInO Schottky Interface.

We report the observation of a magnetocapacitance effect at the interface between Ni and epitaxial nonpolar BiInO thin films at room temperature. A detailed surface study using X-ray photoelectron spectroscopy (XPS) reveals the formation of an intermetallic Ni-Bi alloy at the Ni/BiInO interface and a shift in the Bi 4f and In 3d core levels to higher binding energies with increasing Ni thickness. The latter infers band bending in BiInO, corresponding to the formation of a p-type Schottky barrier.

Performance of point charge embedding schemes for excited states in molecular organic crystals.

Modeling excited state processes in molecular crystals is relevant for several applications. A popular approach for studying excited state molecular crystals is to use cluster models embedded in point charges. In this paper, we compare the performance of several embedding models in predicting excited states and S1-S0 optical gaps for a set of crystals from the X23 molecular crystal database.

In Situ Incorporation of Atomically Precise Au Nanoclusters within Zeolites for Ambient Temperature CO Oxidation.

Preserving ultrasmall sizes of metal particles is a key challenge in the study of heterogeneous metal-based catalysis. Confining the ultrasmall metal clusters in a well-defined crystalline porous zeolite has emerged as a promising approach to stabilize these metal species. Successful encapsulation can be achieved by the addition of ligated metal complexes to zeolite synthesis gel before hydrothermal synthesis.

Comparative Investigation of the Microstructure of MgCl Aqueous Solutions Using Different X-ray Scattering Sources, Raman Spectroscopy, and Atomistic Simulations.

Aqueous solutions of magnesium chloride (MgCl(aq)) are often used to test advances in the theory of electrolyte solutions because they are considered an ideal strong 2:1 electrolyte. However, there is evidence that some ion association occurs in these solutions, even at low concentrations. Even a small ion-pairing constant can have a significant impact on the chemical speciation of ions, so it is important to determine whether ion pairing actually occurs.

The collagen-like protein employs a unique binding mechanism for the recognition of host glycosaminoglycans.

Bacterial adhesion is a fundamental process which enables colonisation of niche environments and is key for infection. However, in , the causative agent of Legionnaires' disease, these processes are not well understood. The collagen-like protein (Lcl) is an extracellular peripheral membrane protein that recognises sulphated glycosaminoglycans (GAGs) on the surface of eukaryotic cells, but also stimulates bacterial aggregation in response to divalent cations.

Studies on 2-((2, 4-dihydroxybenzylidene) amino)-3-phenylpropanoic acid include antimicrobial, antidiabetic, antioxidant, anticancer, hemolysis, and theoretical QSAR.

Studies show that microorganisms resistant to numerous antibiotics spread infections, lengthen hospital stays, and increase fatalities. Amplification factors increase the demand for innovative drug-resistant disease-fighting chemicals. This research synthesised the chiral L-phenyl alanine condensed with a 2, 4-dihydroxy benzaldehyde Schiff base for biological efficacy investigations such as antimicrobial, antidiabetic, DPPH free radical, MTT assay against HeLa cells and hemolysis studies after the characterization.

The impact of stoichiometry on the initial steps of crystal formation: Stability and lifetime of charged triple-ion complexes.

Minerals form in natural systems from solutions with varying ratios of their lattice ions, yet non-stoichiometric conditions have generally been overlooked in investigations of new formation (nucleation) of ionic crystals. Here, we investigated the influence of cation:anion ratio in the solution on the initial steps of nucleation by studying positively and negatively charged triple ion complexes and subsequent particle size evolution. Our model systems are carbonates and sulfates of calcium and barium, as it was recently shown that solution stoichiometry affects the timing and rate of their nucleation.

Long-range atmospheric transport of microplastics across the southern hemisphere.

Airborne microplastics (MPs) can undergo long range transport to remote regions. Yet there is a large knowledge gap regarding the occurrence and burden of MPs in the marine boundary layer, which hampers comprehensive modelling of their global atmospheric transport. In particular, the transport efficiency of MPs with different sizes and morphologies remains uncertain.