This paper presents a deterministic bead-in-droplet ejection (BIDE) technique that regulates the precise distribution of microbeads in an ejected droplet. The deterministic BIDE was realized through the effective integration of a microfluidic single-particle handling technique with a liquid dispensing system. The integrated bead dispenser facilitates the transfer of the desired number of beads ...

The tethered-particle method is a single-molecule technique that has been used to explore the dynamics of a variety of macromolecules of biological interest. We give a theoretical analysis of the particle motions in such experiments. Our analysis reveals that the proximity of the tethered bead to a nearby surface (the microscope slide) gives rise to a volume-exclusion effect, resulting in an en...

A number of welding parameters are responsible for the quality of welds. The modeling of weld bead shape is important for predicting the quality of welds. In this paper, an attempt has been made to develop a back-propagation neural network (BPNN) model for the prediction of reinforcement height and width of bead in GTA bead-on plate welding process. The experimental results were used as testing...

The aim of this study is to investigate the optimization process parameters for Metal inert gas welding (MIG). In the present work, bead-on -plate welds were carried out on MS 5986 Fe 410 carbon steel sheets using Gas Metal Arc Welding (GMAW) process. In this present investigation ER70S-6 solid wire having 1.2 mm diameter was used as an electrode with direct current electrode positive polarity....

In previous studies, we examined three-dimensiional images of a latex bead containing a surface layer of fluorescence whose thickness was determined by physical sectioning. Confocal images of the bead from six different microscopes all exhibited a significantly thicker fluorescent shell than actually present. In contrast, deconvolved wide-field images of the bead produced an image with the corr...

Using a “split –mix” synthesis approach, “One-Bead One-Compound” (OBOC) combinatorial libraries can be generated such that each bead displays only one chemical entity. Tens of thousands to millions of compound-beads can be screened concurrently using a variety of biochemical and cell-based screening methods. Positive beads are then physically isolated for structure determination. Peptide beads ...

A digital microfluidic platform for performing heterogeneous sandwich immunoassays based on efficient handling of magnetic beads is presented in this paper. This approach is based on manipulation of discrete droplets of samples and reagents using electrowetting without the need for channels where the droplets are free to move laterally. Droplet-based manipulation of magnetic beads therefore doe...

We study different configurations of permanent magnets and ferromagnetic circuit, in order to optimize the magnetic field for the so-called “magnetic tweezers” technique, for studing mechanical properties of DNA molecules. The magnetic field is used to pull and twist a micron-sized superparamagnetic bead, tethered to a microscope slide surface by a DNA molecule. The force applied to the bead mu...

RATIONALE Rapidly performing global proteomic screens is an important goal in the post-genomic era. Correlated matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and fluorescent imaging of photocleavable peptide-coded random bead-arrays was evaluated as a critical step in a new method for proteomic screening that combines many of the advantages of MS with fluorescence-base...

To the Editor: A bewildered 7-year-old girl presented with a smooth plastic bead impacted into the right ear canal. On examination the canal was swollen, irritated and tender owing to previous attempts to remove the bead. The bead, measuring 4 mm in diameter, was pushed almost against the eardrum. A further attempt to remove the bead resulted in an agonised yell — further attempts to remove the...