A device for closing a delivery head of a dispensing machine for delivering fluid products includes a stationary support, a drive shaft, which rotates with respect to the stationary support around a vertical axis, and can be moved with respect to the stationary support along the same vertical axis, a cup-shaped closing element carried at the distal end of an arm fixed to a lower end of the drive shaft, and a screw and nut mechanism which controls a translation of the closing element in the direction of the longitudinal axis and a rotation movement to the longitudinal axis using a single actuator.

A method for controlling drop collisions in a drop on demand printing apparatus, comprising discharging a first drop (101) from a first dispenser (111) to move along a first path (103) and discharging a second drop (102) from a second dispenser (112) to move along a second path (104) that crosses with the first path such that the drops are expected to collide and form a combined drop (105), characterized by: measuring the collision of the drops (101, 102); examining whether the collision was effected as expected; if the collision was not effected as expected, altering the parameters of dispensing of the drops (101, 102) from the dispensers (111, 112).

The present disclosure provides methods and compositions for detecting polynucleotides in a sample and for quantifying polynucleotide load in a sample. The polynucleotides can be associated with a disease, disorder, or condition. In some applications, methylated DNA is quantified, e.g., in order to determine the load of polynucleotides in a sample. The present disclosure also provides methods and compositions for determining the load of fetal polynucleotides in a biological sample, e.g., the load of fetal polynucleotides (e.g., DNA, RNA) in maternal plasma. The present disclosure provides methods and compositions for detecting cellular processes such as cellular viability, growth rates, and infection rates. This disclosure also provides compositions and methods for detecting differences in copy number of a target polynucleotide. In some embodiments, the methods and compositions provided herein are useful for diagnosis of fetal genetic abnormalities, when the starting sample is maternal tissue (e.g., blood, plasma). The methods and materials described apply techniques for allowing detection of small, but statistically significant, differences in polynucleotide copy number.

This invention provides compositions and methods for detecting differences in copy number of a target polynucleotide. In some cases, the methods and compositions provided herein are useful for diagnosis of fetal genetic abnormalities, when the starting sample is maternal tissue (e.g., blood, plasma). The methods and materials described apply techniques for allowing detection of small, but statistically significant, differences in polynucleotide copy number.

Methods for preparing all-aqueous emulsions, including stable emulsions or emulsions having high viscosity and/or ultra-low interfacial tension are described. The method includes mixing, combining, or contacting a first electrically charged phase containing a first solute (e.g., dispersed phase) with at least a second phase containing a second solute (e.g., continuous phase). The solutes are incompatible with each other. The electrostatic forces between the two phases induce the formation of droplets of a dispersed phase in a continuous phase. The dispersed and continuous phases contain oppositely charged molecules, such as surfactants or other macromolecules and colloids which stabilize the drops of the dispersed phase. Complex coacervation of the oppositely charged molecules or colloids at the interface of the two aqueous phases results in formation of a membrane or barrier which prevents coalescence or aggregation of the droplets. The membrane also prevents leakage of any encapsulated agents from the droplets.

Methods of partition-based analysis. In an exemplary method, a device having a port fluidically connected to a chamber may be selected. A sample-containing fluid may be placed into the port. The sample-containing fluid may be moved from the port to the chamber. Partitions of the sample-containing fluid may be formed. A monolayer of the partitions in the chamber may be created. At least a portion of the monolayer may be imaged.

Embodiments described herein may be useful for optofluidic devices. For example, optofluidic devices using dynamic fluid lens materials represent an ideal platform to create versatile, reconfigurable, refractive optical components. For example, the articles described herein may be useful as fluidic tunable compound micro-lenses. Such compound micro-lenses may be composed of two or more components (e.g., two or more inner phases) that form stable bi-phase emulsion droplets in outer phases (e.g., aqueous media). In some embodiments, the articles described herein may be useful as light emitting droplets. Advantageously, the plurality of droplets may be configured such that light rays may modified (e.g., via stimulation of the droplets, exposure to an analyte such as a pathogen) to have a detectable emission intensity and/or angle of maximum emission intensity under a particular set of conditions.

Methods of partition-based analysis. In an exemplary method, a device having a port fluidically connected to a chamber may be selected. A sample-containing fluid may be placed into the port. The sample-containing fluid may be moved from the port to the chamber. Partitions of the sample-containing fluid may be formed. A monolayer of the partitions in the chamber may be created. At least a portion of the monolayer may be imaged.

An example device includes a first droplet ejector including a first nozzle to eject droplets of a first fluid, a second droplet ejector including a second nozzle to eject droplets of a second fluid, and a target medium. The example device further includes a mixing volume positioned between the first and second droplet ejectors and the target medium. The mixing volume is to receive the droplets of the first fluid and the droplets of the second fluid, provide mixing of the droplets of the first fluid and the droplets of the second fluid, and provide a mixture to the target medium.

The invention generally relates to methods for forming mixed droplets. In certain embodiments, methods of the invention involve forming a droplet, and contacting the droplet with a fluid stream, wherein a portion of the fluid stream integrates with the droplet to form a mixed droplet.