Aspects of the present disclosure include methods for determining a parameter of a photodetector (e.g., a photodetector in a particle analyzer). Methods according to certain embodiments include irradiating a photodetector positioned in a particle analyzer with a light source (e.g., a continuous wave light source) at a first intensity for a first predetermined time interval, irradiating the photodetector with the light source at a second intensity for a second predetermined time interval, integrating data signals from the photodetector over a period of time that includes the first predetermined interval and the second predetermined interval and determining one or more parameters of the photodetector based on the integrated data signals. Systems (e.g., particle analyzers) having light source and a photodetector for practicing the subject methods are also described. Non-transitory computer readable storage medium having instructions stored thereon for determining a parameter of a photodetector according to the subject methods are also provided.

Aspects of the present disclosure include methods for determining a parameter of a photodetector (e.g., a photodetector in a particle analyzer). Methods according to certain embodiments include irradiating a photodetector positioned in a particle analyzer with a light source (e.g., a continuous wave light source) at a first intensity for a first predetermined time interval, irradiating the photodetector with the light source at a second intensity for a second predetermined time interval, integrating data signals from the photodetector over a period of time that includes the first predetermined interval and the second predetermined interval and determining one or more parameters of the photodetector based on the integrated data signals. Systems (e.g., particle analyzers) having light source and a photodetector for practicing the subject methods are also described. Non-transitory computer readable storage medium having instructions stored thereon for determining a parameter of a photodetector according to the subject methods are also provided.

A simulation device for analyzing behavior of a granular material that includes a plurality of particles includes a first parameter acquisition unit that acquires a first parameter including a parameter relating to the granular material, a second parameter calculation unit that calculates a second parameter, when a particle group including the plurality of particles is coarsely viewed as a single coarse-view particle, the second parameter relating to the coarse-view particle, and a coarse-view particle behavior analysis unit that analyzes a behavior of the coarse-view particle based on the first parameter and the second parameter. The second parameter calculation unit calculates the second parameter by solving a characteristic equation that uses a relationship between an elastic energy of the particle group and an elastic energy of the coarse-view particle.

Generation and use of a focus quality metric that is intensity independent is described. In one example, the focus quality metric is generated by acquiring an image, such as an image of a patterned surface of a flow cell, and processing all or part (e.g., a sub-region or sub-image) to generate a Fourier transform of the respective image data. By way of example, in one embodiment a discrete Fourier transform may be applied to a sub-region of an image of a patterned flow cell surface. A focus quality metric that is intensity independent may be derived from the Fourier transform of the image data.

Methods for evaluating performance a diode laser are provided. In embodiments, methods include receiving a laser beam profile of a diode laser, determining first, second and third laser beam widths at first, second and third laser intensities, respectively, for the laser beam profile, computing a first ratio between the second and third laser beam widths, computing a second ratio between the first and second laser beam widths, evaluating laser performance based on the first and second ratios, and outputting a determination regarding the suitability of the laser for use in a flow cytometry setting. Devices for practicing the subject methods are also provided, and include first and second stages configured to receive a diode laser and beam profiler, respectively. Aspects of the invention further include flow cytometers incorporating a diode laser that has been evaluated by the subject method.

The fine particle measurement apparatus according to the present technology includes a detection section, a multiplication factor setting section, a correction factor calculation section, and a spectrum generation section. The detection section has a plurality of detectors for detecting light from fine particles. The multiplication factor setting section sets a multiplication factor for each of the plurality of detectors. The correction factor calculation section calculates a correction factor on the basis of the set multiplication factor. The spectrum generation section generates spectral data by correcting a value detected by the detector, with the calculated correction factor.

A measuring apparatus includes a flow cell through which a sample containing particles flows, a light source for irradiating light on the sample flowing through the flow cell, a fluorescence detector for detecting the fluorescence generated from the sample irradiated with light from the light source, and a control unit for flowing a positive control sample containing a fluorescent dye through the flow cell, measuring the fluorescence generated from the positive control sample irradiated by the light from the light source via the fluorescence detector, comparing the obtained measurement value and a reference value, and adjusting the detection sensitivity of the fluorescence detector according to the comparison result.

A method of identifying a target analyte in which a sample containing a light-emitting marker configured to bind to the target analyte is irradiated and emission from the light-emitting marker is detected. The light-emitting marker comprises a light-emitting material comprising a group of formula (I): X is one of N and B and Y is the other of N and B; Ar.sup.1 and Ar.sup.2 independently are an unsubstituted or substituted an aromatic or heteroaromatic group which is unsubstituted or substituted with one or more substituents. Ar1 and Ar2 bound to the same X group may be linked by a direct bond or a divalent group. The group of formula (I) may be a repeat unit of a light-emitting polymer. The light-emitting marker may be used in flow cytometry.

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Aspects of the present disclosure include methods for integrating data quality assessment with data acquisition with a flow cytometer. Methods according to certain embodiments include detecting light with a light detection system from a sample irradiated by a light source in a flow stream, generating event data signals in response to events detected with the light detection system, binning the generated event data signals in a plurality of binning windows having overlapping data bins and assessing the plurality of binning windows for outlier events in the generated data signals. Systems having a processor with memory having instructions for practicing the subject methods are also described. Non-transitory computer readable storage medium is also provided.

The present disclosure provides feeder hydrogel particles that can function to support the growth, proliferation, and/or activation of a target cell in culture. The present disclosure also provides methods of culturing target cells with feeder hydrogel particles.