Abstract: A data reproducing apparatus for reproducing data subjected to convolution by partial response, by using maximum likelihood, includes a memory including a plurality of memory arrays which respectively correspond to plural states that the data can take and each of which has a predetermined number of regions each corresponding to a time point. A detecting device periodically detects, from the data, states before the plural states have been shifted, and a control device causes values respectively representing the detected states before shifting to be sequentially stored in the regions of the memory arrays every time detection is performed by the detection device, causing the values previously stored in the memory arrays to be replaced in accordance with the detected states before shifting, and when all values stored in the regions of the memory arrays corresponding to the same time point match, reproducing the data on the basis of the matching value.

Abstract: An information reproducing apparatus for simultaneously reproducing information recorded on a recording medium such as a magneto-optical disk through a plurality of information channels by using a multibeam spot of a laser beam includes a circuit for generating a reproduction signal on the basis of a signal detected from one of the information channels and a signal detected from another information channel. The generating circuit includes a light source, a photodetective sensor, a waveform equalizing circuit, and a binarizing circuit provided in correspondence to each information channel and a data separator for generating reproduction data on the basis of an output of each binarizing circuit and a clock signal.

Abstract: A magnetic head drive device is provided with a magnetic head for generating a magnetic field, a pair of switching elements for switching a current flow direction in the magnetic head, and auxiliary coils respectively connected serially to the switching elements. The current in the magnetic head is controlled by on/off operations of the paired switching elements so as to generate a magnetic field modulated according to an information signal to be recorded. Additional switching elements are serially connected to the auxiliary coils, respectively. In magnetic field modulation recording, the additional switching elements are maintained in the on-state while the modulated magnetic field is generated by the on/off operations of the paired switching elements.

Abstract: An information reproducing apparatus includes a reproduction clock generating device for generating a reproduction clock on the basis of a multivalue signal of a reproduction signal reproduced from an information recording medium, and a reproduction data detecting device for detecting the multivalue signal by using the reproduction clock, and for generating reproduction data synchronized with the reproduction clock. The apparatus further includes a first waveform equalizer for performing waveform equalization of the reproduction signal which is suitable for generation of the reproduction signal, and a second waveform equalizer, arranged independently of the first waveform equalizer, for performing waveform equalization of the reproduction signal which is suitable for detection of the reproduction signal.

Abstract: Polyclonal and monoclonal antibodies are obtained specific to mevalonic acid, having low cross-reactivity with mevalonic acid analogues, such as glutaric acid, 3-methylglutaric acid and 3-hydroxy-3-methylglutaric acid. The antibodies may be used for determination of mevalonic acid providing an immunoassay excellent in sensitivity, specificity and reproducibility.

Abstract: In a magnetooptical recording apparatus, a light beam is radiated onto a magnetooptical recording medium while applying a bias magnetic field to the recording medium in such a manner that at least one of the light beam and the bias magnetic field is modulated according to an information signal. A current to be supplied from a DC power supply to the bias magnetic field applying device is switched by a switch element. The current switched by the switch element is smoothed by a smoothing circuit. The current to be supplied from the DC power supply to the bias magnetic field device is detected by a current detection element. A ratio between ON and OFF time periods of the switch element is changed in correspondence with an error between a value detected by the current detection element and a pre-set reference value.

Abstract: An information reproducing apparatus for reproducing digital information recorded in a recording medium. The apparatus includes a first binarizing unit for binarizing a reproduction signal read out of the recording medium, a differentiating unit for differentiating the reproduction signal read out of the recording medium, a second binarizing unit for binarizing a signal obtained by differentiating the reproduction signal in the differentiating unit, and a determining unit for determining the digital information in units of multiple bits, based on output signals from the first and second binarizing units.

Abstract: In an information recording/reproducing apparatus, a data train of 1 and 0 as recording information is precoded to be converted into a recording data train. The recording data is recorded on a recording medium. A reproduction signal from the recording medium on which the recording data is recorded is obtained by partial response waveform equalization. The recording information has at least one data change from 0 to 1 or 1 to 0 within a predetermined period.

Abstract: Polyclonal and monoclonal antibodies are obtained specific to mevalonic acid, having low cross-reactivity with mevalonic acid analogues, such as glutaric acid, 3-methylglutaric acid and 3-hydroxy-3-methylglutaric acid. The antibodies may be used for determination of mevalonic acid providing an immunoassay excellent in sensitivity, specificity and reproducibility.

Abstract: A drive circuit apparatus for driving a magnetic head includes a magnetic core, a coil wound around the magnetic core, and a unit for supplying current to the coil. The supplying unit includes first and second capacitors and a charging unit such that the second capacitor is charged while the current is supplied to the coil by a charge stored in the first capacitor.

Abstract: Disclosed is a method of recording information on a magnetooptical recording medium, which medium includes a first magnetic layer and a second magnetic layer having a lower Curie temperature and a higher coercive force at room temperature than those of the first magnetic layer. The second magnetic layer is exchange-coupled to the first magnetic layer. The first magnetic layer has a higher compensation temperature than the Curie temperature of the second magnetic layer. The method of recording information includes applying a magnetic field, which is modified in accordance with information from a magnetic head, to the medium to record information on the first magnetic layer and scanning the medium with a light beam to heat the medium to a temperature at least near the Curie temperature of the second magnetic layer so as to transfer the information recorded on the first magnetic layer to the second magnetic layer.

Abstract: A magnetic recording apparatus including a magnetic head having a core formed of a magnetic material is disclosed. If the size of a cross section of the core is A.times.B (A.gtoreq.B), the distance d between a core end surface and a recording layer of the recording medium is selected so as to satisfy the relationship:0.1.times.B<d<0.4.times.A.The magnetic field applied to the recording layer facing the core end surface is thereby made uniform. A method of applying a magnetic field to a magnetic recording carrier using such an apparatus also is disclosed.