Heterogeneous micellar solubilization within lyotropic liquid crystals interfaces.

The solubilization of sodium diclofenac (Na-DFC) in a glycerol monooleate-based emulsion triggers series of structural changes. Incorporation of Na-DFC, leads to formation of a reverse hexagonal mesophase between 2 and 5 wt% Na-DFC. Between 6 and 9 wt% Na-DFC, the hexagonal symmetry gradually transitions to a disordered lamellar mesophase.

Magnetic Resonance Study of Bulky CVD Diamond Disc.

Diamonds produced using chemical vapor deposition (CVD) have found many applications in various fields of science and technology. Many applications involve polycrystalline CVD diamond films of micron thicknesses. However, a variety of optical, thermal, mechanical, and radiation sensing applications require more bulky CVD diamond samples.

Light-Induced Self-Assembled Polydiacetylene/Carbon Dot Functional "Honeycomb".

The design of functional supramolecular assemblies from individual molecular building blocks is a fundamental challenge in chemistry and material science. We report on the fabrication of "honeycomb" films by light-induced coassembly of diacetylene derivatives and carbon dots. Specifically, modulating noncovalent interactions between the carbon dots, macrocyclic diacetylene, and anthraquinone diacetylene facilitates formation of thin films exhibiting a long-range, uniform pore structure.

Dynamic Thermodynamic Resolution of Racemic 1,1'-Binaphthyl-2,2'-diol (BINOL).

A dynamic thermodynamic resolution method for converting (/)-BINOL (1,1'-binaphthyl-2,2'-diol) into ()-BINOL in 100% theoretical yield is reported. This technique involves mixing (/)-BINOL with -benzyl cinchonidinium bromide (1 equiv) and a [Cu(tmeda)(μ-OH)]Br (2.5 mol %) redox catalyst in acetonitrile.

Ultrasound features of benign paediatric lumps: radiology-pathology correlation.

Ultrasonography is an appropriate first-line imaging technique for the characterisation of paediatric lumps, given its relative accessibility and absence of radiation exposure. Together with a thorough history and examination, ultrasonography can help to distinguish benign lesions from malignancy. It can also aid further characterisation of benign lesions to inform onward investigation and management.

Multicopper Clusters Enable Oxidative Phenol Macrocyclization (OxPM) of Peptides.

The biosynthesis of glycopeptide antibiotics such as vancomycin and other biologically active biaryl-bridged and diaryl ether-linked macrocyclic peptides includes key enzymatic oxidative phenol macrocyclization(s) of linear precursors. However, a simple and step-economical biomimetic version of this transformation remains underdeveloped. Here, we report highly efficient conditions for preparing biaryl-bridged and diaryl ether-linked macrocyclic peptides based on multicopper(II) clusters.

Optical and electronic spin properties of fluorescent micro- and nanodiamonds upon prolonged ultrahigh-temperature annealing.

High-temperature annealing is a promising but still mainly unexplored method for enhancing spin properties of negatively charged nitrogen-vacancy (NV) centers in diamond particles. After high-energy irradiation, the formation of NV centers in diamond particles is typically accomplished via annealing at temperatures in the range of 800-900 °C for 1-2 h to promote vacancy diffusion. Here, we investigate the effects of conventional annealing (900 °C for 2 h) against annealing at a much higher temperature of 1600 °C for the same annealing duration for particles ranging in size from 100 nm to 15 m using electron paramagnetic resonance and optical characterization.

Photoelectrochemical alcohols oxidation over polymeric carbon nitride photoanodes with simultaneous H production.

The photoelectrochemical oxidation of organic molecules into valuable chemicals is a promising technology, but its development is hampered by the poor stability of photoanodic materials in aqueous solutions, low faradaic efficiency, low product selectivity, and a narrow working pH range. Here, we demonstrate the synthesis of value-added aldehydes and carboxylic acids with clean hydrogen (H) production in water using a photoelectrochemical cell based solely on polymeric carbon nitride (CN) as the photoanode. Isotope labeling measurements and DFT calculations reveal a preferential adsorption of benzyl alcohol and molecular oxygen to the CN layer, enabling fast proton abstraction and oxygen reduction, which leads to the synthesis of an aldehyde at the first step.

All-inorganic ferric wheel based on hexaniobate-anion linkers.

Utilizing the inherent ability of Lindquist-type hexaniobate cluster-anions, [NbO], to serve as oxo-donor ligands in complexes with transition-metal cations, we report the synthesis and characterization of the first all-inorganic "ferric" wheel, Li[(NbO)Fe(OH)]·88HO, comprised of eight Fe atoms linked by eight hexaniobate cluster-anion ligands. Bond valence sum analysis of the X-ray structure and the synthesis conditions themselves indicate that the Fe atoms are in the +3 oxidation state. This is confirmed by magnetic susceptibility and electron paramagnetic resonance (EPR) measurements which indicate the presence of high spin ( = 5/2) Fe(III) ions.

Triphenyllead Hydroperoxide: A 1D Coordination Peroxo Polymer, Single-Crystal-to-Single-Crystal Disproportionation to a Superoxo/Hydroxo Complex, and Application in Catalysis.

The synthesis, transformation, and application in catalysis of triphenyllead hydroperoxide, the first dioxygen lead complex, are described. Triphenyllead hydroperoxide is characterized by Pb nuclear magnetic resonance (NMR), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, and single-crystal X-ray diffraction, revealing the first one-dimensional (1D) coordination peroxo polymer. Photolytic isomorphous transformation of PhPbOOH yields a mixed hydroxo/superoxo crystalline structure, the first nonalkali superoxo crystalline metal salt, which is stable up to 100 °C.

A role for synaptonemal complex in meiotic mismatch repair.

A large subset of meiotic recombination intermediates form within the physical context of synaptonemal complex (SC), but the functional relationship between SC structure and homologous recombination remains obscure. Our prior analysis of strains deficient for SC central element proteins demonstrated that tripartite SC is dispensable for interhomolog recombination in Saccharomyces cerevisiae. Here, we report that while dispensable for recombination per se, SC proteins promote efficient mismatch repair at interhomolog recombination sites.

Soluble Complexes of Cobalt Oxide Fragments Bring the Unique CO Photoreduction Activity of a Bulk Material into the Flexible Domain of Molecular Science.

The deposition of metal oxides is essential to the fabrication of numerous multicomponent solid-state devices and catalysts. However, the reproducible formation of homogeneous metal oxide films or of nanoparticle dispersions at solid interfaces remains an ongoing challenge. Here we report that molecular hexaniobate cluster anion complexes of structurally and electronically distinct fragments of cubic-spinel and monoclinic CoO can serve as tractable yet well-defined functional analogues of bulk cobalt oxide.

Apoplexy in a previously undiagnosed pituitary macroadenoma in the setting of recent COVID-19 infection.

Pituitary apoplexy is an endocrine emergency, which commonly presents as hypopituitarism. Prompt diagnosis and treatment can be both life and vision saving. There are a growing number of published case reports postulating a link between COVID-19 and pituitary apoplexy.

PVP-coated Gd-grafted nanodiamonds as a novel and potentially safer contrast agent for in vivo MRI.

Purpose: Testing the potential use of saline suspension of polyvinylpyrrolidone (PVP)-coated gadolinium(Gd)-grafted detonation nanodiamonds (DND) as a novel contrast agent in MRI.

Methods: Stable saline suspensions of highly purified de-agglomerated Gd-grafted DND particles coated by a PVP protective shell were prepared. T and T proton relaxivities of the suspensions with varying gadolinium concentration were measured at 8 Tesla.

Room-temperature hyperpolarization of polycrystalline samples with optically polarized triplet electrons: pentacene or nitrogen-vacancy center in diamond?

We demonstrate room-temperature C hyperpolarization by dynamic nuclear polarization (DNP) using optically polarized triplet electron spins in two polycrystalline systems: pentacene-doped [carboxyl-C] benzoic acid and microdiamonds containing nitrogen-vacancy (NV) centers. For both samples, the integrated solid effect (ISE) is used to polarize the C spin system in magnetic fields of 350-400 mT. In the benzoic acid sample, the C spin polarization is enhanced by up to 0.

Identification of Barium Hydroxo-Hydroperoxostannate Precursor for Low-Temperature Formation of Perovskite Barium Stannate.

A breakthrough "superoxide colloidal solution route" for low-temperature synthesis of barium and strontium stannate perovskites and their doped analogues was recently introduced. The synthesis starts from hydrogen peroxide-rich stannate solutions and yields a so-called "crystalline superoxide molecular cluster" that is converted by low temperature (<300 °C) to the respective perovskites. In this paper, the so-called "crystalline superoxide molecular cluster" is identified as a superoxide-free, barium trihydroxo(hydroperoxo)peroxostannate, BaSn(OH)(OOH)(OO) phase (BHHPS).

Thiourea-Mediated Halogenation of Alcohols.

The halogenation of alcohols under mild conditions expedited by the presence of substoichiometric amounts of thiourea additives is presented. The amount of thiourea added dictates the pathway of the reaction, which may diverge from the desired halogenation reaction toward oxidation of the alcohol, in the absence of thiourea, or toward starting material recovery when excess thiourea is used. Both bromination and chlorination were highly efficient for primary, secondary, tertiary, and benzyl alcohols and tolerate a broad range of functional groups.

Mitochondria membrane transformations in colon and prostate cancer and their biological implications.

Mitochondria have emerged as important determinants in cancer progression and malignancy. However, the role of mitochondrial membranes in cancer onset and progression has not been thoroughly investigated. This study compares the structural and functional properties of mitochondrial membranes in prostate and colon cancer cells in comparison to normal mitochondria, and possible therapeutic implications of these membrane changes.

How to Identify, Attribute, and Quantify Triplet Defects in Ensembles of Small Nanoparticles.

Nanodiamonds containing negatively charged triplet (having an electron spin = 1) nitrogen-vacancy (NV) centers are an extraordinary room-temperature quantum system, whose electron spins may be polarized and read out optically even in a single nanocrystal. In this Viewpoint we promote a simple but reliable method to identify, attribute, and quantify these triplet defects in a polycrystalline sample using electron paramagnetic resonance (EPR) spectroscopy. The characterization relies on a specific "forbidden" transition ("Δ = 2"), which appears at about half the central magnetic field and shows a remarkably small anisotropy.

Examining relaxivities in suspensions of nanodiamonds grafted by magnetic entities: comparison of two approaches.

Objectives: Detonation nanodiamonds (DND) with Gd ions directly grafted to the DND surface have recently demonstrated enhanced relaxivity for protons in aqueous suspensions. Herewith, the relaxivity measurements were done on a series of suspensions with the gadolinium content varied by changing number of Gd ions grafted per each DND particle whereas the DND content in each suspension was kept the same. Such an approach to vary the contrast agent content differs from that commonly used in the relaxivity measurements.

Photoredox-Mediated Reaction of gem-Diborylalkenes: Reactivity Toward Diverse 1,1-Bisborylalkanes.

The use of gem-diborylalkenes as radical-reactive groups is explored for the first time. These reactions provide an efficient and general method for the photochemical conversion of gem-diborylalkenes to rapidly access 1,1-bisborylalkanes. This method exploits a novel photoredox decarboxylative radical addition to gem-diborylalkenes to afford α-gem-diboryl carbon-centered radicals, which benefit from additional stability by virtue of an interaction with the empty p-orbitals on borons.

Monodisperse Five-Nanometer-Sized Detonation Nanodiamonds Enriched in Nitrogen-Vacancy Centers.

Nanodiamonds containing negatively charged nitrogen-vacancy (NV) centers are versatile nanosensors thanks to their optical and spin properties. While currently most fluorescent nanodiamonds in use have at least a size of a few tens of nanometers, the challenge lies in engineering the smallest nanodiamonds containing a single NV defect. Such a tiny nanocrystal with a single NV center is an "optical spin label" for biomolecules, which can be detected in a fluorescence microscope.

Structural Characterization of Reconstituted Bioactive-Loaded Nanodomains after Embedding in Films Using Electron Paramagnetic Resonance and Self-Diffusion Nuclear Magnetic Resonance Techniques.

Pharmaceutical applications of microemulsions (MEs) as drug delivery vehicles are recently gaining scientific and practical interests. Most MEs are able to solubilize bioactive molecules, but, at present, they cannot guarantee either controlled release of the drugs or significant advantage in the bioavailability of the bioactives. This study proposes to incorporate the modified ME structures, or nanodomains, into a natural polymeric film, to be used as a stable and capacious reservoir of drug-loaded nanodomains.

Micro-characterization of modified microemulsions loaded with gossypol, pure and extracted from cottonseed.

Microemulsions (MEs) have gained increasing interest as carriers of hydrophobic bioactives in the last decades. However, it is still difficult to control the uptake and the release of bioactives directly extracted from plants. In this study, modified ME nanodroplets (nano-sized self-assembled liquids, NSSLs) were employed as extraction medium of gossypol, a toxic component of cottonseed.

Review Article: Synthesis, properties, and applications of fluorescent diamond particles.

Diamond particles containing color centers-fluorescent crystallographic defects embedded within the diamond lattice-outperform other classes of fluorophores by providing a combination of unmatched photostability, intriguing coupled magneto-optical properties, intrinsic biocompatibility, and outstanding mechanical and chemical robustness. This exceptional combination of properties positions fluorescent diamond particles as unique fluorophores with emerging applications in a variety of fields, including bioimaging, ultrasensitive metrology at the nanoscale, fluorescent tags in industrial applications, and even potentially as magnetic resonance imaging contrast agents. However, production of fluorescent nanodiamond (FND) is nontrivial, since it requires irradiation with high-energy particles to displace carbon atoms and create vacancies-a primary constituent in the majority color centers.