Abstract: Embodiments of the present invention provide an improved transformation method whereby the peripheral pulse waveform is filtered to separate different phases which make up the waveform. The separate phases are transformed before being re-combined to provide an estimated intra-arterial transfer function. For example, in one embodiment the peripheral pulse waveform is filtered by a first high pass filter, and a copy of the peripheral pulse waveform filtered by a second high pass filter, having a different cut-off frequency. The two filtered waveforms may then be further processed, for example by being added back to original wave-form, and are then multiplexed together in a time division manner to provide a final waveform.

Abstract: Embodiments of the present invention provide an improved transformation method whereby the peripheral pulse waveform is filtered to separate different phases which make up the waveform. The separate phases are transformed before being re-combined to provide an estimated intra-arterial transfer function. For example, in one embodiment the peripheral pulse waveform is filtered by a first high pass filter, and a copy of the peripheral pulse waveform filtered by a second high pass filter, having a different cut-off frequency. The two filtered waveforms may then be further processed, for example by being added back to original wave-form, and are then multiplexed together in a time division manner to provide a final waveform.

Abstract: Apparatus (2) for determining respiratory muscle endurance of a person, which apparatus (2) comprises a mouthpiece (4) through which the person inspires, load-providing means (6) for providing a pressure against which the person inspires, and pressure control means (8) for controlling the pressure, the pressure control means (8) being such that it controls the pressure in response to a breathing pattern of the person.

Abstract: A method of measuring endothelial function in a person (2), which method comprises applying pressure to one arm of the person (2) such as to restrict blood flow in the arm (6), releasing the pressure in order to cause an increase in blood flow in the arm (6) due to reactive hyperaemia, and then measuring the difference in pulse propagation time between the two arms (6, 8) of the person.

Abstract: A rotary variable orifice valve (42) comprising a cylindrical member (46), a sleeve (52) which is a rotational fit with respect to the cylindrical member (46), and an orifice (44). In one embodiment, the cylindrical member (46) has an aperture (50), and the sleeve (52) has the orifice (44). The aperture (50) and the orifice (44) are positioned such that they overlap as the sleeve (52) is rotated by a motor (12).

Abstract: Apparatus (2) for measuring the strength of a person's respiratory muscles, which apparatus (2) comprises a mouthpiece (4) for the person, a flow transducer, a pressure transducer (6), a variable orifice valve (10), a motor (12) for operating the variable orifice valve (10), and microprocessor control means (8), the microprocessor control means being such that it is able to control the motor (12) to cause the variable orifice valve (10) to vary its orifice size and thereby to maintain a constant predetermined pressure and enable the measurement of the flow rate generated by the person, or to maintain a constant predetermined flow rate and enable the measurement of the pressure generated by the person.

Abstract: A method of measuring endothelial function in a person (2), which method comprises applying pressure to one arm of the person (2) such as to restrict blood flow in the arm (6), releasing the pressure in order to cause an increase in blood flow in the arm (6) due to reactive hyperaemia, and then measuring the difference in pulse propagation time between the two arms (6, 8) of the person.