A nonlinear optical signal-treating apparatus can suppress the distortion of pulse light to be inputted into an optical fiber to an allowable level or less. The breastpump assembly includes a substantially rigid plastic housing connected to the extending portion of the breast hood. As a result, flame stability and sensitivity of the detector can be maintained by the methods and apparatus of the present disclosure. The radiation generator includes a first group of light-emitting diodes to provide light pulses having a wavelength centered around approximately 640 nm, a second group of LEDs to provide light pulses having a wavelength centered around approximately 780 nm, and a third group of LEDs to provide light pulses having a wavelength centered around approximately 880 nm. A requisition from a requester for a target item is received.