Abstract: A transducer system for a weighing scale having a flexure mode crystal resonator includes a parallelogram linkage for supporting the load platform of the scale, a mounting structure for mounting the crystal resonator between two pivotally connected mounting arms, and a coupling assembly for coupling force from the parallelogram linkage to one arm of the mounting structure.

Abstract: A human reproduction indexing device for indicating the calendar dates for days of a menstrual cycle on which the probability of conception is the greatest includes a generally rectangular member having indicia representing the calendar dates for the days of given months positioned in three separate columns on the member and indicator-index columns aligned and positioned adjacent each of the separate columns on the member. When the calendar date corresponding to the day of the onset of the menses is known, the indicator-index columns indicate the calendar dates for an eight day interval starting ten days after the indexed date to provide the time interval during which ovulation should occur and thus the days on which the probability of conception are maximized.

Abstract: A human reproduction indexing device for indicating the calendar dates for days of a menstrual cycle on which the probability of conception is the greatest includes a generally circular base member having indicia representing the calendar dates for the days of a given month disposed around the periphery thereof, and an index member rotatably secured to the base member and having an index and an indicator disposed thereon and configured so that when the index is aligned with the calendar date corresponding to the day of the onset of the menses, the indicator is positioned to indicate the calendar dates for a seven day interval starting ten days after the indexed date thereby indicating the time interval during which ovulation should occur and thus the days on which the probability of conception are the greatest.

Abstract: A system for purging the aperture and surrounding portions of a blood cell counter of dirt, debris, and previous sample liquid. A sample tube extends from a source of either sample liquid or cleansing solution to a small gap between the aperture and housing assembly. A purge line is connected between an annular portion surrounding the gap and a pump which supplies negative pressure. Due to the geometry of the sample tube, gap, annulus, and purge line, a high pressure drop occurs across the gap and the liquid flows at relatively high velocity past the aperture to facilitate cleaning.