Barrels are patterned groups of neurons in rodent somatosensory cortex that correspond one to one with the animal's facial whiskers. Dirichlet domains are a class of convex polygon found frequently in nature, often arising by nucleation from center points. Analytic and graphical methods were devised to verify the hypothesis that Dirichlet domains accurately describe the adult barrel fields of n...

The recognition of β-barrel membrane proteins based on their sequence is more challenging than the recognition of α-helical membrane proteins. This goal could benefit from a better understanding of the physical determinants of transmembrane β-barrel structure. To that end, we first extend the IMM1 implicit membrane model in a way that allows the modeling of membrane proteins with an internal aq...

Cobalamin-independent methionine synthase (MetE) catalyzes the transfer of a methyl group from methyltetrahydrofolate to L-homocysteine (Hcy) without using an intermediate methyl carrier. Although MetE displays no detectable sequence homology with cobalamin-dependent methionine synthase (MetH), both enzymes require zinc for activation and binding of Hcy. Crystallographic analyses of MetE from T...

Compressive tests on clay tiles used in historical masonry timbrel vaults are hindered by the relatively small thickness of specimens, resulting buckling or confinement problems depending loading direction. This paper presents an experimental campaign and a numerical validation novel testing setup for estimating compressive strength thin vaults. The focuses two different types corresponding to ...

OmpW is an eight-stranded 21 kDa molecular-weight beta-barrel protein from the outer membrane of Gram-negative bacteria. It is a major antigen in bacterial infections and has implications in antibiotic resistance and in the oxidative degradation of organic compounds. OmpW from Escherichia coli was cloned and the protein was expressed in inclusion bodies. A method for refolding and purification ...

Abstract. This paper presents a part from one broader research project on ribbed vaults. The main goal is to generate parametric objects library for vaults, suitable both HBIM system, structural analysis or Cultural Heritage dissemination. Starting Treatises study we have analyzed different classification system and terminology used vaults components in languages, especially English, French, Sp...

Could propane from Alaska’s North Slope reduce energy costs for electric utilities and residential space heating, water heating, and cooking demands? We explored the hypothesis that propane is a viable alternative for fourteen selected communities along the Yukon and Kuskokwim Rivers, coastal Alaska, and Fairbanks. Our analysis forecasts propane and fuel prices at the wholesale and retail level...

α-Helical coiled coils are ubiquitous protein-protein-interaction domains. They share a relatively straightforward sequence repeat, which directs the folding and assembly of amphipathic α-helices. The helices can combine in a number of oligomerisation states and topologies to direct a wide variety of protein assemblies. Although in nature parallel dimers, trimers and tetramers dominate, the pot...

Substrate channeling has emerged as a common mechanism for enzymatic intermediate transfer. A conspicuous gap in knowledge concerns the use of covalent lysine imines in the transfer of carbonyl-group-containing intermediates, despite their wideuse in enzymatic catalysis. Here we show how imine chemistry operates in the transfer of covalent intermediates in pyridoxal 5'-phosphate biosynthesis by...