Abstract: A respiratory monitoring system with improved detection of oxygen consumption is described. The system uses one or two mixing chambers and samples gases at selective locations for reliable detection of oxygen over extended periods of time with autonomous detection of calibration drift. The system can be used for indirect calorimetry and monitoring health of a subject.

Abstract: A cell selection chamber includes an inlet and an outlet, with a reservoir positioned therebetween and configured to allow for fluid flow from the inlet to the outlet. The reservoir contains a plurality of microbubbles, which are each at least partially coated with streptavidin. An upstream membrane is positioned between the inlet and the reservoir, while a downstream membrane is positioned between the outlet and the reservoir. The membranes include a plurality of pores each having a diameter that is less than a diameter of the microbubbles. In use, a heterogeneous population of cells is mixed with a biotinylated antibody additive and then conveyed into the cell selection chamber so as to cause target cells of the heterogeneous population of cells to become bound to the microbubbles and to cause other cells of the heterogeneous population of cells to flow out of the cell selection chamber as unbound cells.

Abstract: A conventional flow tube for a metabolic cart is usually a straight length of pipe whose inner diameter is fixed by the respiratory burden imposed by the flow tube on the user, with a smaller diameter imposing a higher respiratory burden. The ratio of the straight flow tube's length to diameter is fixed by fluid dynamics, so increasing the flow tube's diameter causes the flow tube's length to increase. As the flow tube gets longer, it exerts more torque on the user's neck and jaw, creating discomfort. Reducing the flow tube's length causes an undesired increase in the respiratory burden but increasing the flow tube's diameter to reduce the respiratory burden makes the flow tube less comfortable, making the flow tube unconformable, hard to breathe through, or both. Bending the flow tube makes it possible to increase the flow tube's propagation length without increasing the flow tube's lever arm length.

Abstract: A cell processing system includes at least one processor connectable to a source container filled with a biological fluid, the processor including a spinning membrane configured to receive and separate target cells from the biological fluid, the target cells exiting at a first outlet, first and second containers selectively connected to the first outlet; and a magnet. The system also includes a controller configured to operate the spinning membrane to receive biological fluid and to direct the target cells to the first container, to pause to permit magnetic particles to be associated with the target cells in the first container, to operate the spinning membrane to receive the contents of the first container with the magnet applied to the target cells associated with the magnetic particles, to remove or deactivate the magnet, and to transfer the target cells to the second container.

Abstract: Probability models of user behaviour are generated by tracking and recording user progress through health programs consisting of individual activities. Historical user engagement with a program or activities is aggregated into probability models that estimate future user behaviours and engagement with different activities. Using probability models, a next best engagement engine identifies and suggests health programs that have been determined to maximize the aggregate overall expected value to the user of being presented with an activity sequence. To model the probability of a user completing different activities in the future given past user behaviours, machine-learning techniques that train on input data sets observed over time are utilized.

Abstract: A conventional flow tube for a metabolic cart is usually a straight length of pipe whose inner diameter is fixed by the respiratory burden imposed by the flow tube on the user, with a smaller diameter imposing a higher respiratory burden. The ratio of the straight flow tube's length to diameter is fixed by fluid dynamics, so increasing the flow tube's diameter causes the flow tube's length to increase. As the flow tube gets longer, it exerts more torque on the user's neck and jaw, creating discomfort. Reducing the flow tube's length causes an undesired increase in the respiratory burden but increasing the flow tube's diameter to reduce the respiratory burden makes the flow tube less comfortable, making the flow tube unconformable, hard to breathe through, or both. Bending the flow tube makes it possible to increase the flow tube's propagation length without increasing the flow tube's lever arm length.

Abstract: A method of operating a magnetic selector is provided. The magnetic selector includes a housing including a floor having a floor surface, a magnet carrier disposed on an opposite side of the floor from the floor surface and having at least one magnet disposed thereon, the magnet carrier being moveable relative to the floor between a first state wherein the magnet carrier is adjacent the floor and a second state wherein the magnet carrier is spaced from the floor. The method includes disposing a container on the floor surface, moving the magnet carrier to the first state to apply a magnetic field to a fluid in the container, moving the magnet carrier to the second state from the first state to disengage the magnetic field from the container, and removing the container.

Abstract: A dilution refrigerator is provided. The dilution refrigerator includes a first thermal stage configured to be cooled to a first temperature, a second thermal stage configured to be cooled to a second temperature lower than the first temperature, and a vacuum chamber housing the first thermal stage and the second thermal stage. The dilution refrigerator also includes a first suspension system configured to suspend the first thermal stage from the vacuum chamber, and a second suspension system configured to suspend the second thermal stage from the vacuum chamber independently from the first thermal stage.

Abstract: A dilution refrigerator is provided. The dilution refrigerator includes an outer vacuum chamber comprising at least one substantially planar surface and an opening in the at least one substantially planar surface configured to provide access to an interior of the outer vacuum chamber.

Abstract: A distributed refrigeration system is provided. The distributed refrigeration system comprises a pre-cooling system configured to be thermally coupled to two or more cryogenic devices and to provide a first cooling stage to the two or more cryogenic devices. The two or more cryogenic devices may be two or more of a dilution refrigerator, a low-temperature microscopy system, a 3He refrigeration system, and/or a superconducting CMOS system.

Abstract: A dilution refrigerator is provided. The dilution refrigerator includes a plurality of thermal stages configured to be cooled to a plurality of temperatures. A coldest thermal stage of the plurality of thermal stages is disposed above warmer thermal stages of the plurality of thermal stages such that the coldest thermal stage is positioned furthest from a floor supporting the dilution refrigerator.

Abstract: A dilution refrigerator is provided. The dilution refrigerator includes a plurality of thermalization plates configured to be cooled to a plurality of temperatures, and a first thermalization plate of the plurality of thermalization plates includes an integrated heat exchanger. The integrated heat exchanger includes channels formed in the first thermalization plate, and the channels are configured to allow helium to flow through the first thermalization plate during operation of the dilution refrigerator to improve heat exchange and cooling power of the dilution refrigerator.

Abstract: A conventional flow tube for a metabolic cart is usually a straight length of pipe whose inner diameter is fixed by the respiratory burden imposed by the flow tube on the user, with a smaller diameter imposing a higher respiratory burden. The ratio of the straight flow tube's length to diameter is fixed by fluid dynamics, so increasing the flow tube's diameter causes the flow tube's length to increase. As the flow tube gets longer, it exerts more torque on the user's neck and jaw, creating discomfort. Reducing the flow tube's length causes an undesired increase in the respiratory burden but increasing the flow tube's diameter to reduce the respiratory burden makes the flow tube less comfortable, making the flow tube unconformable, hard to breathe through, or both. Bending the flow tube, e.g., in an L shape, makes it possible to increase the flow tube's propagation length without increasing the flow tube's lever arm length.

Abstract: A fluid dynamic valve passively allows fluid flow out of a moving stream in one flow direction and not in the reverse. This allows the collection of fluid from a single direction of an AC fluid flow. The siphoned portion of the flow has a flow rate proportional to the mainstream flow. This device can collect exhaled breath or selective entrenchment during inhale. In one orientation, it can meter aerosolized particles into an inhale breath stream for pulmonary delivery, without complicated breath timing or drug loss due to drug adsorption to the back of the throat. Alternatively, a user can breathe through the device and a proportional amount, relative to the volumetric flow rate, of each exhale can flow into an auxiliary chamber for analysis. In addition, the device has a low respiratory burden and is comfortable to use.

Abstract: A fluid dynamic valve passively allows fluid flow out of a moving stream in one flow direction and not in the reverse. This allows the collection of fluid from a single direction of an AC fluid flow. The siphoned portion of the flow has a flow rate proportional to the mainstream flow. This device can collect exhaled breath or selective entrenchment during inhale. In one orientation, it can meter aerosolized particles into an inhale breath stream for pulmonary delivery, without complicated breath timing or drug loss due to drug adsorption to the back of the throat. Alternatively, a user can breathe through the device and a proportional amount, relative to the volumetric flow rate, of each exhale can flow into an auxiliary chamber for analysis. In addition, the device has a low respiratory burden and is comfortable to use.

Abstract: A method is provided for isolating and labeling discrete features in a spectral radiographic image recorded as a set of images in different energy channels. The disclosed method involves creating a profile for each of at least some pixels in the spectral radiographic image. The profiles are sequences of pixel values, in which each pixel value is a photon count or a similar radiographic exposure value indicative of the attenuation of a portion of the scanning beam in a respective energy channel. Iterative hierarchical clustering is used to cluster the pixels on the basis of their respective profiles. Labels are assigned to one or more of the resulting clusters. In implementations, each label can be associated with an inferred material composition or with an inference that the material composition is unknown.

Abstract: Systems, apparatus, and methods related to modeling, monitoring, and/or managing metabolism of a subject include measuring a respiratory quotient (RQ) level in a subject and/or optimizing and executing a nonlinear feedback model to model energy substrate utilization in the subject based on at least one of a macronutrient composition and caloric value of food consumed by the subject, an intensity and duration of activity by the subject, a rate and maximum capacity of glycogen storage in the subject, a rate and maximum capacity of de novo lipogenesis in the subject, a quality and duration of sleep by the subject, and/or an RQ level in the subject.

Abstract: A fluid dynamic valve passively allows fluid flow out of a moving stream in one flow direction and not in the reverse. This allows the collection of fluid from a single direction of an AC fluid flow. The siphoned portion of the flow has a flow rate proportional to the mainstream flow. This device can collect exhaled breath or selective entrenchment during inhale. In one orientation, it can meter aerosolized particles into an inhale breath stream for pulmonary delivery, without complicated breath timing or possible large scale drug loss due to drug adsorption to the back of the throat. Alternatively, a user can breathe through the device and a proportional amount, relative to the volumetric flow rate, of each exhale can flow into an auxiliary chamber for analysis. In this arrangement, the fluid dynamic valve replaces the mechanical pump in a metabolic measurement apparatus. It collects a proportional volume of the exhale and none of the inhale for mixing-chamber breath analysis.

Abstract: A conventional flow tube for a metabolic cart is usually a straight length of pipe whose inner diameter is fixed by the respiratory burden imposed by the flow tube on the user, with a smaller diameter imposing a higher respiratory burden. The ratio of the straight flow tube's length to diameter is fixed by fluid dynamics, so increasing the flow tube's diameter causes the flow tube's length to increase. As the flow tube gets longer, it exerts more torque on the user's neck and jaw, creating discomfort. Reducing the flow tube's length causes an undesired increase in the respiratory burden but increasing the flow tube's diameter to reduce the respiratory burden makes the flow tube less comfortable, making the flow tube unconformable, hard to breathe through, or both. Bending the flow tube, e.g., in an L shape, makes it possible to increase the flow tube's propagation length without increasing the flow tube's lever arm length.

Abstract: A cell processing system includes at least one processor connectable to a source container filled with a biological fluid, the processor including a spinning membrane configured to receive and separate target cells from the biological fluid, the target cells exiting at a first outlet, first and second containers selectively connected to the first outlet; and a magnet. The system also includes a controller configured to operate the spinning membrane to receive biological fluid and to direct the target cells to the first container, to pause to permit magnetic particles to be associated with the target cells in the first container, to operate the spinning membrane to receive the contents of the first container with the magnet applied to the target cells associated with the magnetic particles, to remove or deactivate the magnet, and to transfer the target cells to the second container.