Structure of a bacterial type IV secretion core complex at subnanometre resolution

Type IV secretion (T4S) systems are able to transport DNAs and/or proteins through the membranes of bacteria. They form large multiprotein complexes consisting of 12 proteins termed VirB1-11 and VirD4. VirB7, 9 and 10 assemble into a 1.07 MegaDalton membrane-spanning core complex (CC), around which all other components assemble. This complex is made of two parts, the O-layer inserted in the outer membrane and the I-layer inserted in the inner membrane. While the structure of the O-layer has been solved by X-ray crystallography, there is no detailed structural information on the I-layer. Using high-resolution cryo-electron microscopy and molecular modelling combined with biochemical approaches, we determined the I-layer structure and located its various components in the electron density. Our results provide new structural insights on the CC, from which the essential features of T4S system mechanisms can be derived

Intensity-based dynamic speckle method for analysis of variable-rate dynamic events

We study efficiency of intensity-based dynamic speckle method for characterization of dynamic events which occur at variable rate in time within the temporal averaging interval. We checked ability of the method to describe the speed evolution by i) numerical simulation at variable speed, ii) processing of speckle patterns obtained from phase distributions fed to a SLM at controllable change of the temporal correlation radius of speckle intensity fluctuations and iii) conducting experiments with a polymer solution drying by using a hot-stage. The numerical and SLM simulation experiments allowed for modification of the used estimates in order to obtain relevant informatio

A Cationic Diode Based on Asymmetric Nafion® Film Deposits

A thin film of Nafion®, of approximately 5 microm thickness, asymmetrically deposited onto a 6 microm thick film of poly(ethylene terephthalate) (PET) fabricated with a 5, 10, 20, or 40 microm microhole, is shown to exhibit prominent ionic diode behaviour involving cation charge carrier ("cationic diode"). The phenomenon is characterized via voltammetric, chronoamperometric, and impedance methods. Phenomenologically, current rectification effects are comparable to those observed in nano-cone devices where space-charge layer effects dominate. However, for microhole diodes a resistive, a limiting, and an over-limiting potential domain can be identified and concentration polarization in solution is shown to dominate in the closed state.</p

Ionic diodes based on regenerated α-cellulose films deposited asymmetrically onto a microhole

Cellulose films of approximately 5 mm thickness, reconstituted from ionic liquid media onto a poly-ethylene-terephthalate (PET) film with a 5, 10, 20, or 40 mm diameter microhole, show current rectification when immersed in aqueous NaCl. For “asymmetric cellulose deposits” this rectification, or ionic diode behaviour, is then investigated as a function of ionic strength and microhole diameter. Future applications are envisaged in sustainable cellulose-based desalination, sensing, or energy harvesting processes<br/

A Population-based and Clinical Cohort Validation of the Novel Consensus Definition of Metabolic Hyperferritinemia

Background: There is limited data on the clinical significance of metabolic hyperferritinemia (MHF) based on the most recent consensus. We aimed to validate the clinical outcomes of MHF in general population and biopsy-proven metabolic dysfunction-associated fatty liver disease (MAFLD) patients. Methods: NHANES database and PERSONS cohort were included. MHF was defined as elevated serum ferritin with metabolic dysfunction (MD) and stratified into different grades according to ferritin (grade 1: 200 [females]/300 [males] - 550 ng/ml; grade 2: 550 - 1000 ng/ml; grade 3: &gt; 1000 ng/ml). The clinical outcomes, including all-cause death, comorbidities and liver histology were compared between non-MHF and MHF in adjusted models. Results: In NHANES, compared with non-MHF with MD, MHF was related to higher risks of advanced fibrosis (FIB-4, P = 0.036), elevated albumin-creatinine ratio (UACR, P = 0.001) and sarcopenia (P = 0.013). Although the association between all grades of MHF and mortality was insignificant (P = 0.122), grades 2/3 was associated with increased mortality (P = 0.029). While comparing with non-MHF without MD, the harmful effects of MHF were more significant in mortality (P &lt; 0.001), elevated UACR (P &lt; 0.001), cardiovascular disease (P = 0.028), and sarcopenia (P &lt; 0.001). In PERSONS cohort, MHF was associated with more advanced grades of steatosis (P &lt; 0.001), lobular inflammation (P &lt; 0.001), advanced fibrosis (P = 0.017), and more severe hepatocellular iron deposition (P &lt; 0.001). Conclusions: Both in general population and at-risk individuals with MAFLD, MHF was related with poorer clinical outcomes

ADVANCES IN GEOMETRY INDEPENDENT APPROXIMATIONS

We present recent advances in geometry independent field approximations. The GIFT approach is a generalisation of isogeometric analysis where the approximation used to describe the field variables no-longer has to be identical to the approximation used to describe the geometry of the domain. As such, the geometry can be described using usual CAD representations, e.g. NURBS, which are the most common in the CAD area, whilst local refinement and meshes approximations can be used to describe the field variables, enabling local adaptivity. We show in which cases the approach passes the patch test and present applications to various mechanics, fracture and multi-physics problems

Electron-phonon physics from first principles using the EPW code

EPW is an open-source software for $\textit{ab initio}$ calculations of electron-phonon interactions and related materials properties. The code combines density functional perturbation theory and maximally-localized Wannier functions to efficiently compute electron-phonon coupling matrix elements on ultra-fine Brillouin zone grids. This data is employed for predictive calculations of temperature-dependent properties and phonon-assisted quantum processes in bulk solids and low-dimensional materials. Here, we report on significant new developments in the code that occurred during the period 2016-2022, namely: a transport module for the calculation of charge carrier mobility and conductivity under electric and magnetic fields within the $\textit{ab initio}$ Boltzmann transport equation; a superconductivity module for the calculation of critical temperature and gap structure in phonon-mediated superconductors within the $\textit{ab initio}$ anisotropic multi-band Eliashberg theory; an optics module for calculations of phonon-assisted indirect transitions; a module for the calculation of small and large polarons without supercells using the $\textit{ab initio}$ polaron equations; and a module for calculating electron-phonon couplings, band structure renormalization, and temperature-dependent optical spectra using the special displacement method. For each capability, we outline the methodology and implementation, and provide example calculations. We describe recent code refactoring to prepare EPW for exascale architectures, we discuss efficient parallelization strategies, and report on extreme parallel scaling tests.Comment: 61 pages, 9 figure

A Cationic Diode Based on Asymmetric Nafion® Film Deposits

A thin film of Nafion®, of approximately 5 microm thickness, asymmetrically deposited onto a 6 microm thick film of poly(ethylene terephthalate) (PET) fabricated with a 5, 10, 20, or 40 microm microhole, is shown to exhibit prominent ionic diode behaviour involving cation charge carrier ("cationic diode"). The phenomenon is characterized via voltammetric, chronoamperometric, and impedance methods. Phenomenologically, current rectification effects are comparable to those observed in nano-cone devices where space-charge layer effects dominate. However, for microhole diodes a resistive, a limiting, and an over-limiting potential domain can be identified and concentration polarization in solution is shown to dominate in the closed state