Abstract: Systems and methods are provided for counting particles in a fluid flow. In an aspect, coordinates of particles are obtained from video data of particles in a fluid, the video data made up of a sequence of image frames. The particle positions are linked in each pair of consecutive image frames of the video data. The linked particle positions are used to calculate particle trajectories through sequential image frames of the video data, and the particles are counted based on the particle trajectory. In another aspect, the particle positons within each image frame are transformed to estimated positions within a common coordinate frame. The estimated particle positions of a particle are grouped into a cluster center, and the particle count is calculated based on the cluster centers.

Abstract: The field of the invention generally relates to sample collection, for example of a sample being an exhaled breath. In particular, an integrated device is disclosed herein comprising a silicon chip for sampling particulate matter from a sample and for analysis, preferably by a protocol using thermocycling, of the particulate matter as collected from the sample. Further, point-of-care (PoC) and self-use analysis systems compatible with the integrated device, and methods related to sample collection and/or analysis using the same, are also disclosed.

Abstract: There is provided a device (300;500;700) for collecting fluorescent light (322) emitted by particles (304) in a medium (302). The device (300;500;700) comprises a substrate (308) having a chamber (306) for holding the medium (302) including the particles (304) being capable of emitting fluorescent light (322). A first waveguide (310), which is arranged to receive and guide excitation light along a first direction (313), extends through the chamber (306). Fluorescent light (322) emitted by the particles (304) following an excitation is collected by the first waveguide (310). The device (300;500;700) further comprises a coupler (316;516) which includes a second waveguide (317) arranged to output collected fluorescent light (326) at one of its ends (318).

Abstract: The disclosure relates to an arrangement (100) in a capillary driven fluid system for metering a predetermined volume of sample fluid. The arrangement comprises a sample reservoir (SR) arranged to receive a sample fluid, a first channel (C1) which is in fluid communication with the sample reservoir (SR) and which branches off into a second channel (C2) ending at a first valve (V1) and a third channel (C3) ending at a second valve (V2). The second channel (C2) and the third channel (C3) together have a predetermined volume, and the first channel (C1) is arranged to draw sample fluid from the sample reservoir (SR) by use of capillary forces to fill the second channel (C2) and the third channel (C3) with the predetermined volume of sample fluid. By selectively opening the first valve (V1) and the second valve (V2), a capillary driven flow may be formed, thereby causing the predetermined volume of sample fluid to flow out through the first valve (V1).

Abstract: There is provided a microfluidic device for reversing a flow through a microfluidic channel. The microfluidic device comprises a first microfluidic channel extending between a first inlet and a first outlet, a second microfluidic channel which fluidically connects a first point of the first microfluidic channel to a second outlet via a first valve, a third microfluidic channel which fluidically connects a second point of the first microfluidic channel to a second inlet via a second valve, the second point being located between the first point and the first outlet, and at least one circuit for opening the first valve and the second valve. The first and the second valves are arranged to be initially closed, Upon opening of the first and the second valve during use, the flow direction through the first microfluidic channel between the first point and the second point is reversed.

Abstract: There is provided an arrangement (100) which allows for mixing a first fluid with a second fluid at a predetermined volume mixing ratio in a capillary driven fluidic system. The arrangement (100) allows filling an initially empty mixing chamber (110) with the first fluid. The arrangement then allows emptying a predetermined fraction of the first fluid from the mixing chamber (110) such as to form an empty space in the mixing chamber (110). The arrangement then allows filling the empty space of the mixing chamber (110) with the second fluid, thereby allowing a predetermined volume of the first fluid to mix with a predetermined volume of the second fluid over time.

Abstract: There is provided a connecting interface for fluidically interconnecting microfluidic channels. The connecting interface comprises one or more substrates which collectively define a first microfluidic channel which includes a connecting region for fluidically connecting the first microfluidic channel to a second microfluidic channel. The connecting interface further comprises at least one slit in an outer surface of one of the one or more substrates, wherein the at least one slit provides a fluid passage from the outer surface to the connecting region of the first microfluidic channel, and the at least one slit has at least one dimension extending beyond the connecting region along a direction parallel to the outer surface.

Abstract: Systems and methods are provided for counting particles in a fluid flow. In an aspect, coordinates of particles are obtained from video data of particles in a fluid, the video data made up of a sequence of image frames. The particle positions are linked in each pair of consecutive image frames of the video data. The linked particle positions are used to calculate particle trajectories through sequential image frames of the video data, and the particles are counted based on the particle trajectory. In another aspect, the particle positions within each image frame are transformed to estimated positions within a common coordinate frame. The estimated particle positions of a particle are grouped into a cluster center, and the particle count is calculated based on the cluster centers.

Abstract: The disclosure relates to an arrangement (100?) in a capillary driven fluidic system for preventing wicking of a fluid along an edge (105) between a first substrate (110?) and a second substrate (120?), said arrangement comprising: a first substrate (110?) including a microfluidic channel (114) arranged to house the fluid, a second substrate (120?) arranged to cover a portion of the first substrate (110?), wherein the microfluidic channel (134) of the first substrate (110?) meets the second structure (120?) at a position (124) along an edge (105) defined between the first (110?) and second (120?) substrates, wherein the first and the second substrate collectively define a trench (130) for stopping wicking of the fluid along the edge (105), said trench (130) being arranged in at least one of the first substrate (110?) and the second substrate (120?), and located at a distance from said position (124) along the edge (105) and intersecting the edge (105).

Abstract: There is provided a microfluidic device for reversing a flow through a microfluidic channel. The microfluidic device comprises a first microfluidic channel extending between a first inlet and a first outlet, a second microfluidic channel which fluidically connects a first point of the first microfluidic channel to a second outlet via a first valve, a third microfluidic channel which fluidically connects a second point of the first microfluidic channel to a second inlet via a second valve, the second point being located between the first point and the first outlet, and at least one circuit for opening the first valve and the second valve. The first and the second valves are arranged to be initially closed, Upon opening of the first and the second valve during use, the flow direction through the first microfluidic channel between the first point and the second point is reversed.

Abstract: There is provided an arrangement in a capillary driven microfluidic system for dissolving a reagent in a fluid. The arrangement (200) comprises a channel (102) for receiving a fluid at a first end, a valve (105) arranged at a second end of the channel so as to control a flow of the fluid to stop as it reaches the second end of the channel, and an actuator (108) for opening the valve (105) a predetermined time after receipt of the fluid by the channel (102). The arrangement further comprises one or more structures (106) for holding a dried reagent. The one or more structures (106) each has a width (W2) which is larger than a width (W1) of the channel (102), and the one or more structures are coupled to a side wall of the channel such that the fluid is allowed to enter the one or more structures from the channel, dissolve the dried reagent held therein, and diffuse back into the channel.

Abstract: A system for lens-free imaging includes a processor in communication with a lens-free image sensor. The processor is programmed to operate the image sensor to obtain a hologram ??. The processor is further programmed to generate, from the hologram, a reconstructed image X and phase W at a focal depth z using an assumption of sparsity.

Abstract: There is provided an optical system comprising a photonic integrated circuit which is integrated on a platform and an element having a first surface being attached to the platform. The element has a groove in the first surface, and the groove is filled with a medium having a refractive index which is different from that of the element. The groove has a surface with a normal that forms an angle with respect to a predetermined light direction, thereby allowing changing a direction of light which is incident on the platform along the predetermined light direction. The element and the medium filling the groove are transparent for a wavelength range of the light which is incident on the platform.

Abstract: There is provided an optical system for coupling light into a waveguide. The optical system comprising a coupler arranged at a portion of the waveguide. The coupler has a surface with a grating structure for directing light into the waveguide formed therein. A cladding layer embeds the coupler and an optical path changing structure is formed in the cladding layer. The optical path changing structure has a refractive surface and a reflective surface, each forming an acute angle with respect to the surface of the coupler. Light which enters the optical path changing structure through the refractive surface will be refracted and directed towards the reflective surface. The reflective surface is arranged to reflect the light such that it is directed towards the grating structure of the coupler along a direction suitable for efficient coupling of light into the waveguide.

Abstract: A method of directing a wavefront of coherent radiation through a sample of objects in a suspension, capturing an interference pattern between the wavefront of coherent radiation and a wavefront of the diffracted by the object with an image sensor, numerically determining the focal plane of at least one object, and numerically reconstructing a de-focused image of the at least one object from the interference pattern in an image plane which is substantially parallel to the image sensor and in a plane with a predetermined offset from the focal plane. The method further includes identifying at least one portion in the defocused image corresponding to the at least one object in the sample, and calculating from each of said portions at least one feature of the corresponding object.