A new concept for the manipulation of superparamagnetic beads inside a microfluidic chip is presented in this paper. The concept allows for bead actuation orthogonal to the flow direction inside a microchannel. Basic manipulation functionalities were studied by means of finite element simulations and results were oval-shaped steady state oscillations with bead velocities up to 500 μm/s. The wid...

Moving objects produce trajectories. We describe a data model for trajectories and trajectory samples and an efficient way of modeling uncertainty via beads for trajectory samples. We study transformations of the ambient space for which important physical properties of trajectories, such as speed, are invariant. We also determine which transformations preserve beads. We give conceptually easy f...

DNA sequencing with a solid-state nanopore requires a reduction of the translocation speeds of single-stranded DNA (ssDNA) over 10 μs/base. In this study, we report that a nanometre-sized bead structure constructed around a nanopore can reduce the moving speed of ssDNA to 270 μs/base by adjusting the diameter of the bead and its surface chemical group. This decelerating effect originates from t...

Dielectrophoresis was used to stretch and suspend actin filaments across a trench etched between two electrodes patterned on a glass slide. Optical tweezers were used to bring a motor protein-coated bead into close proximity to a pre-selected, suspended actin filament, facilitating the attachment of the myosin-coated bead to the filament. The clearance beneath the filament allowed the bead to m...

Thermocouples are constructed of two dissimilar metals such as Chromel and Constantan (Type E) or Nicrosil and Nisil (Type N). The two dissimilar metals are bonded together on one end of both wires with a weld bead. This bead is exposed to the thermal environment of interest. If there is a temperature difference between the bead and the other end of the thermocouple wires, a voltage will appear...

Energy-dependent protein degradation is studied through the dual bead ClpXP motility assay. Processing of folded proteins involves recognition, unfolding, translocation, and degradation stages. A dual optical trap, in a passive force-clamp geometry, exhibits bead-to-bead displacements that directly follow subprocesses underlying protein degradation. Discrete nanometer-scale displacements of the...

A multi-response optimization problem was developed in search of an optimal parametric combination to yield favorable bead geometry of bead-on-plate weldments produced by submerged arc welding. Taguchi’s L25 orthogonal array design was employed to optimize the results within experimental limits. The objective functions were selected in terms of responses of bead geometry, viz. height of reinfor...

An empirical calibration method for fused bead analysis by XRF spectrometry with advanced corrections has been established. These calibrations include matrix effects, weighing inaccuracies, loss on ignition (LOI), gain on ignition (GOI), decomposition of oxidizing agent and evaporation of flux. The corrections for these common sources of error in the fusion method are incorporated into the basi...

An external force-assisted near-field illumination biosensor (EFA-NI biosensor) detects a target substance that is propelled through an evanescent field by an external force. The target substance is sandwiched between an antibody coupled to a magnetic bead and an antibody coupled to a polystyrene bead. The external force is supplied by a magnetic field. The magnetic bead propels the target subs...

Magnetic micro- and nanoparticles ('magnetic beads') have been used to advantage in many microfluidic devices for sensitive antigen (Ag) detection. Today, assays that use as read-out of the signal the number count of immobilized beads on a surface for quantification of a sample's analyte concentration have been among the most sensitive and have allowed protein detection lower than the fgmL(-1) ...