Abstract:
Methods of detecting the presence or absence of a microorganism comprising detecting the presence or absence of microbiological target molecules in a test sample employing electrophoresis comprising immobilized capture probes are described. Methods for detecting mutation sites within a putative mutant target molecule are also disclosed.
Abstract:
Apparatus and method for determining at least one parameter, e.g., concentration, of at least one analyte, e.g., urea, of a biological sample, e.g., urine. A biological sample particularly suitable for the apparatus and method of this invention is urine. In general, spectroscopic measurements can be used to quantify the concentrations of one or more analytes in a biological sample. In order to obtain concentration values of certain analytes, such as hemoglobin and bilirubin, visible light absorption spectroscopy can be used. In order to obtain concentration values of other analytes, such as urea, creatinine, glucose, ketones, and protein, infrared light absorption spectroscopy can be used. The apparatus and method of this invention utilize one or more mathematical techniques to improve the accuracy of measurement of parameters of analytes in a biological sample. The invention also provides an apparatus and method for measuring the refractive index of a sample of biological fluid while making spectroscopic measurements substantially simultaneously.
Abstract:
A method and apparatus are provided for the determination of levels of components of coolants and heat exchange fluids, particularly monoethylene - and monopropylene - glycol content. Refractometric and gravimetric values are taken and the volume fraction of the individual components obtained by inverting a system of linear equations. A microprocessor controlled field test apparatus can compute the various values to be determined.
Abstract:
A refractometric apparatus and method for monitoring the percentage of water in hydraulic fluids employ a temperature sensitive device allowing a user to obtain accurate and correct readings of various measured properties. In particular, the temperature sensitive member comprises a prism-wedge-mirror combination in conjunction with a bimetallic strip. The combination ensures the proper angular displacement of a light beam inside the refractometric apparatus and, therefore, the correct reading of a parameter to be measured.
Abstract:
A differential refractometry apparatus that maintains optimal optical alignment of components while accurately providing differential refractometry measurement at elevated temperatures. The differential refractometry apparatus has a first thermal zone (10), a thermal isolation zone and a second thermal zone (14). The first thermal zone (10) is configured to be located in an oven and exposed to higher temperatures. The thermal isolation zone is located adjacent to the first thermal zone (10) and acts as a barrier to the conduction of heat from the first thermal zone (10) into the second thermal zone (14). The second thermal zone (14) is at a relatively lower temperature than the first thermal zone (10) and its temperature is regulated using a thermal electric cooler located at its base. A flow cell (22), a mirror (24) which reflects the incoming light beam, and an imaging lens are located in the first thermal zone. An LED and a photodiode detector are located in the second thermal zone and are encased in thermally stable blocks with low coefficients of thermal expansion.
Abstract:
A refractometer and a method for measuring the refractive index of a lens (80), wherein a thin insert (86) in the form of a pad of a flexible transparent material attached to a rigid transparent sheet (82), is lightly pressed onto a surface of the lens (80) under test, such that the pad surface effectively acquires the same profile as the lens surface. The focal length or power of the lens (80) is first measured without the insert, and the measurement is then repeated with the insert positioned first in contact with one surface of the lens (80), and then in contact with the other surface. The use of equations derived from the classical lens formula then enables the refractive index of the lens (80) to be easily and quickly determined. The apparatus and method also enables the measurement of the refractive index of lenses of low power.
Abstract:
A method/an apparatus for sorting products includes a flexible concertina-like shield (3) sealingly engaging a portion of the surface of the product (2) at one end to receive electromagnetic radiation transmitted through the product, at the other end of the shield electromagnetic radiation receiving means (4) is positioned and a control means to selectively position the shielding means at or about the product selected (fig.3).
Abstract:
The present invention consists of a method and apparatus for identifying articles, particularly fruit or vegetables. The technique involves analysing either the reflected or transmitted electromagnetic energy (preferably electromagnetic energy corresponding to the optical spectrum). The reflected or transmitted energy may be diffracted using a diffraction grating whereby the diffracted spectrum is compared with a number of pre-determined spectra. The electromagnetic energy source may be stepped laser, sequentially switched light emitting diodes or other suitable radiation source. Instead of using a particular frequency of electromagnetic energy for the energy source, the source may provide a relatively narrow band of electromagnetic energy with the detection means being sensitive to a wide band. Identification of the characteristics of the reflection or transmission could be by way of wavelength shift. The present invention may find application in fruit sorting (at the growing location and the retail location) or similar process control type situations involving articles such as fruit or vegetables.
Abstract:
A refractometric apparatus (10) and method for monitoring the percentage of water in hydraulic fluids employs a temperature sensitive device allowing a user to obtain accurate and correct readings of various measured properties on the reticle (92) of the apparatus (10). In particular, the temperature sensitive member comprises a prism-wedge-mirror combination (38, 58) in conjunction with a bimetallic strip (60). The combination ensures the proper angular displacement of a light beam inside the refractometric apparatus (10) and, therefore, the correct reading on the reticle (92).
Abstract:
In an analytic process using porous silicon, a substance is detected or its concentration in a fluid is determined, based on the change in optical properties of porous silicon as a function of the index of refraction of the substance or of the fluid containing the substance present in the pores of the porous silicon. An analytic device using porous silicon to detect a substance or determe the concentration of a substance in a fluid consists of a component which is at least partly made of porous silicon, the optical property of which is dependent on the index of refraction of the substance or of the fluid containing the substance, where a change in the optical property of porous silicon can be measured to indicate detection of the substance or to determine the concentration in the pores of the porous silicon.