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Nosocomial or hospital‐acquired infections (HAIs) have a major impact on mortality worldwide. Enterococcus and Staphylococcus are among the leading causes of HAIs and thus are important pathogens to control mainly due to their increased antibiotic resistance. The gold‐standard diagnostic methods for HAIs are time‐consuming, which hinders timely and adequate treatment. Therefore, the development of fast and accurate diagnostic tools is an urgent demand. In this study, we combined the sensitivity of magnetoresistive (MR) sensors, the portability of a lab‐on‐chip platform, and the specificity of phage receptor binding proteins (RBPs) as probes for the rapid and multiplex detection of Enterococcus and Staphylococcus. For this, bacterial cells were firstly labelled with magnetic nanoparticles (MNPs) functionalized with RBPs and then measured on the MR sensors. The results indicate that the RBP‐MNPS provided a specific individual and simultaneous capture of more than 70% of Enterococcus and Staphylococcus cells. Moreover, high signals from the MR sensors were obtained for these samples, providing the detection of both pathogens at low concentrations (10 CFU/ml) in less than 2 h. Overall, the lab‐on‐chip MR platform herein presented holds great potential to be used as a point‐of‐care for the rapid, sensitive and specific multiplex diagnosis of bacterial infections. [ABSTRACT FROM AUTHOR]

One of the critical issues in spintronics‐based technologies is to increase the data storage density. Current strategy is based on shrinking the devices size down to tens of nanometers, or several nanometers, which is reaching its limit. A new proposal is to use multi‐level cells (MLCs) to store more than two bits in each cell. In this work, the multi‐level switching is realized in CoFeB/MgO/CoFeB based nano‐scale single perpendicular magnetic tunnel junctions (p‐MTJs) with three or four stable resistance states. A large range of writing currents for each state is obtained, accompanying with a good repeatability of set‐reset operations between different states. The developed multi‐domain model perfectly matches the experimental results, reflecting the magnetic behaviors during multi‐level switching. Furthermore, current‐driven domain wall (DW) motion is revealed in the circular p‐MTJs, where the DW position can be reversibly manipulated by applied current. To design high‐performance multi‐level p‐MTJs, the parameter diagrams are calculated, suggesting various feasible strategies to improve the multi‐level switching through materials optimization and devices geometry. In summary, the demonstration of multi‐level switching in single p‐MTJ shows the high potential of realizing the new generation of p‐MTJ‐based multi‐level spintronic devices, such as multi‐level memories and spin‐neuron devices. [ABSTRACT FROM AUTHOR]

Directed cell migration is essential for many biological processes, such as embryonic development or cancer progression. Cell contractility and adhesion to the extracellular matrix are known to regulate cell locomotion machinery. However, the cross-talk between extrinsic and intrinsic factors at the molecular level on the biophysical mechanism of three dimensional (3D)-directed cell migration is still unclear. In this work, a novel physiologically relevant in vitro model of the extracellular microenvironment is used to reveal how the topological anisotropy of the extracellular matrix synergizes with actomyosin contractility to modulate directional cell migration morphodynamics. This study shows that cells seeded on polarized 3D matrices display asymmetric protrusion morphodynamics and in-vivo-like phenotypes. It is found that matrix anisotropy significantly enhances cell directionality, but strikingly, not the invasion distance of cells. In Rho-inhibited cells, matrix anisotropy counteracts the lack of actomyosin-driven forces to stabilize cell directionality suggesting a myosin-II-independent mechanism for cell guidance. Finally, this study shows that on isotropic 3D environments, cell directionality is independent of actomyosin contractility. Altogether, this study provides novel quantitative data on the biomechanical regulation of directional cell motion and shows the important regulatory role of matrix anisotropy and actomyosin forces to guide cell migration in 3D microenvironments. [ABSTRACT FROM AUTHOR]

In this study, the authors report on two different electronic interfaces for low‐power integrated circuits electric current monitoring through current‐to‐frequency (I–f) conversion schemes. This proposal displays the intrinsic advantages of the quasi‐digital systems regarding direct interfacing and self‐calibrating capabilities. In addition, as current‐sensing devices, they have made use of the giant magnetoresistance (GMR) technology because of its high sensitivity and compatibility with standard complementary metal oxide semiconductor processes. Single elements and Wheatstone bridges based on spin‐valves and magnetic tunnel junctions have been considered. In this sense, schematic‐level simulations for integration in Austria Microsystems 0.35 μm technology have been corroborated by means of experimental measurements with the help of printed circuit board prototypes and real GMR devices. Tables with relevant parameters (silicon area, power consumption, sensitivity etc.) have been constructed as practical tools for designers. Electric currents down to 2 μA have been resolved in this way. [ABSTRACT FROM AUTHOR]

Abstract: Osteocytes are organized in functional syncytia collectively referred to as the osteocytic lacunar–canalicular system (OLCS). The osteocytes are interconnected through gap junctions between their cytoplasmic processes, which pass through narrow passageways referred to as osteocytic canaliculi. There are two possible ways molecules can be transported throughout the OLCS: via the cytoplasmic processes and their gap junctions, and via the pericellular space in the osteocytic canaliculi. Transport of minerals and small molecules through a spatially well-organized OLCS is vital for bone mineral homeostasis, mechanosensing, and bone remodeling control. Recently, osteocyte-derived molecules – sclerostin, dentin matrix protein-1, fibroblast growth factor 23 (FGF23) – have been put in evidence as they may be related to osteocytic functions such as mechanosensing, regulation of bone remodeling, and so forth. FGF23 regulates serum phosphate concentration by affecting renal function, while sclerostin can inhibit osteoblastic activities. In our observations, FGF23 and sclerostin synthesis seemed to be associated with the spatial regularity of the OLCS. This review will introduce our recent morphological studies on the regularity of OLCS and the synthesis of osteocyte-derived FGF23 and sclerostin. [Copyright &y& Elsevier]