Abstract: Certain aspects of the present disclosure provide a surgical cassette configured to engage a first plurality of rollers of a first roller head. The cassette comprises a face coupled to a first substrate, the face being at a first angle with respect to the first roller head's axis of rotation and a wall of first substrate being at a second angle with respect to the axis of rotation, wherein the first angle is different from the second angle. The cassette also comprises a first sheet positioned on the wall's surface, wherein the first sheet and the wall form first one or more pump segments configured to engage the first plurality of rollers in a position where force applied by each one of the first plurality of rollers on the first one or more pump segments has a direction that is not parallel to the first roller head's axis of rotation.

Abstract: A sensor assembly to measure particulate matter is described. The sensor assembly includes a voltage source, a sensor electrode, a grounded assembly, an integration capacitor, and a current meter. The sensor electrode is coupled to the voltage source to receive a voltage. The sensor electrode is disposed within a directed and controlled exhaust flow within the sensor assembly to facilitate particle agglomeration into particulate matter structures at a surface of the sensor electrode. The grounded assembly is coupled to a ground reference and disposed at a distance from the sensor electrode. The integration capacitor is coupled to a negative side of the voltage source. The integration capacitor is configured to integrate in time current pulses from charge transfers from the sensor electrode of the particulate matter structures.

Abstract: A system and method for blocking access by a network device to specific network resources by comparing a specific resource identifier against entries in a blacklist and facilitating a connection accordingly. A request for a connection to a specific network resource identified by a specific identifier is received and compared against entries in a stored blacklist. When the specific identifier matches one of the entries within the blacklist, the connection to the specific network resource is denied and when the specific identifier does not match one of the entries within the blacklist, then the connection to the specific network resource is allowed. The system further includes a blacklist database that maintains an updated copy of the blacklist and the network device retrieves an updated version upon the occurrence of specific events.