Endoscopy-induced complication of barotrauma with concomitant benign pneumoperitoneum.

Endoscopy is widely used for diagnostic and therapeutic purposes in modern clinical practice. Two of the less common complications are barotrauma and benign pneumoperitoneum. In isolation, these two complications have been successfully managed conservatively.

Obesity Is Associated with Attenuated Tissue Immunity in COVID-19.

Obesity affects 40% of U.S. adults, is associated with a proinflammatory state, and presents a significant risk factor for the development of severe coronavirus disease (COVID-19).

Cutaneous manifestations of phosphate solution extravasation.

Extravasation injuries are common in patients receiving multiple intravenous infusions. Although such injuries are closely associated with the infusion of cytotoxic chemotherapy, they have also been been associated with extravasation of noncytotoxic drugs. Extravasation injuries can lead to skin ulceration and nerve and tendon damage, and therefore to permanent disability.

Expanded porphyrin-like structures based on twinned triphenylenes.

Triphenylene twins are intriguing structures, and those bridged through their 3,6-positions by dipyrromethene units give a new class of macrocycles that can be viewed as rigid, expanded porphyrin derivatives in which coplanarity is enforced in a formally antiaromatic π system. Somewhat surprisingly, however, macrocyclization leads to significant overall stabilization of the dipyrromethene chromophores.

Unexpected phenol production from arylboronic acids under palladium-free conditions; organocatalyzed air oxidation.

An intriguing class of quinones that efficiently catalyze the air oxidation (overall hydroxylation) of arylboronic acids to the corresponding phenol is reported. Autocatalysis in the parent system is particularly efficient and leads to rapid, quantitative synthesis of quinones such as 4 from boronic acid 1 at room temperature using air as stoichiometric oxidant. The efficiency results from a balance between two-stage conjugate addition and migration with each step driven by aromatization of a naphthalene fragment.

Prediction of EPR spectra of liquid crystals with doped spin probes from fully atomistic molecular dynamics simulations: exploring molecular order and dynamics at the phase transition.

Liquid crystals spin their secrets: Electron paramagnetic resonance (EPR) spectra are predicted directly and completely from fully atomistic molecular dynamics (MD) simulations of 4-cyano-4-n-pentylbiphenyl (5CB) nematic liquid crystals with a doped nitroxide spin probe (depicted in yellow; red curve = simulated and blue curve = measured EPR spectrum).

Muon spin spectroscopy of the discotic liquid crystal HAT6.

Avoided level crossing muon spin resonance (ALC-muSR) has been used to study the cyclohexadienyl-type radicals produced by the addition of muonium (Mu) to the discotic liquid crystal HAT6 (2,3,6,7,10,11-hexahexyloxytriphenylene) in the crystalline (Cr) phase, the hexagonal columnar mesophase (Col(h)) and isotropic (I) phase. In the Cr phase unpaired electron spin density can be transferred from the radical to neighboring HAT6 molecules depending on the overlap of their pi-systems and hence on the relative orientation of the triphenylene rings. The two Delta(1) resonances in the ALC-muSR spectra of the Cr phase indicate that the neighboring HAT6 molecules have two preferred orientations with respect to the radical: one which results in negligible spin density transfer and a second where 17% of the unpaired spin density is transferred.

Antiaromatic twinned triphenylene discotics showing nematic phases and 2-dimensional pi-overlap in the solid state.

Construction of formally antiaromatic discotic twins based on dehydroannulene cores linked through non-adjacent positions on triphenylenes gives stable molecules with intriguing molecular and supramolecular properties and, unlike the majority of discotic triphenylenes and similar materials, the twins form nematic mesophases on heating.

Synthesis of crown ether-linked discotic triphenylenes.

Novel triphenylene dimers linked by a central crown ether core have been synthesized and characterized. The crown ether is most conveniently formed as a final step to permit purification and isolation of ion-free material, and extension of the protocol permits synthesis of triad structures linked though a 27-crown-9 macrocycle. The latter compounds present a new discotic motif that supports mesophase formation.

Probing the structural factors influencing columnar mesophase formation and stability in triphenylene discotics.

Series of structurally related substituted triphenylene derivatives were designed and synthesised to interrogate key features which determine mesophase formation and stability, and to challenge the general conclusions previously proposed by us and others. It is apparent that no single, simple principle can be universally applied.

Electron paramagnetic resonance spectra simulation directly from molecular dynamics trajectories of a liquid crystal with a doped paramagnetic spin probe.

We report simulation of EPR spectra directly and entirely from trajectories generated from molecular dynamics simulations. Results are reported for a model 3beta-DOXYL-5alpha-cholestane spin probe in a coarse-grained solvent representing a 5CB nematic host. The results are in excellent agreement with the experimental spectra.

A bromine catalysed dimerisation of alpha,alpha'-dihalomonopyrrolo-TTF.

Dihalomonopyrrolo-TTF undergoes a bromine catalysed dimerisation reaction to yield a novel type of extended TTF derivative.

Perylenophthalocyanines.

The first perylenophthalocyanines have been synthesised using a Diels-Alder reaction between dialkylperylenes and fumaronitrile as the key step towards the dinitrile precursors. As expected the octaalkylperylenophthalocyanines show red-shifted absorption spectra. They are high melting solids that do not display mesophase behaviour at accessible temperatures.

Aryl trihydroxyborates: easily isolated discrete species convenient for direct application in coupling reactions.

A conceptually and practically simple alternative approach to the use of arylboron species as the organometallic component in cross-coupling processes is described whereby trihydroxyborate salts are isolated and directly employed. The protocol derives practical benefit from the ease and convenience of the isolation and subsequent use of the discrete borate salts, eliminates the need for additional base, and aids the use of correct reaction stoichiometry.

Macrodiscotic triphenylenophthalocyanines.

The first heavily substituted triphenylenophthalocyanines have been synthesised and found to be mesogenic.