Abstract: Nucleic acids may be labeled by complexing the alkylating moiety of a labeling reagent into a single-stranded nucleic acid to form a complex and activating the complex to cause covalent bonding between the reagent and the nucleic acid. Preferably, the labeled nucleic acid is a single-stranded hybridization probe for detecting nucleic acid sequences capable of hybridizing with a hybridizing region of the nucleic acid. Also preferably the label moiety is non-radioactive. The labeling reagent is of the formula:[A--[B--Lwhere A is an alkylating moiety, B is a divalent organic moiety of the formula: ##STR1## where Y is O, NH or N--CHO, x is a number from 1 to 4, y is a number from 2 to 4, and L is a monovalent label moiety, wherein B is exclusive of any portion of the alkylating and label moieties.Preferably A is a 4-methylene-substituted psoralen moiety, and most preferably A is a 4'-methylene-substituted-4,5',8-trimethylpsoralen moiety and L is biotin.

Abstract: Nucleic acids may be labeled by intercalating the alkylating intercalation moiety of a labeling reagent into a partially double-stranded nucleic acid to form a complex and activating the complex to cause covalent bonding between the reagent and the nucleic acid. Preferably, the labeled nucleic acid is a hybridization probe for detecting nucleic acid sequences capable of hybridizing with a hybridizing region of the nucleic acid. Also preferably the label moiety is non-radioactive. The labeling reagent is of the formula:[A--[B--Lwhere A is an alkylating intercalation moiety, B is a divalent organic moiety of the formula: ##STR1## where Y is O, NH or N--CHO, x is a number from 1 to 4, y is a number from 2 to 4, and L is a monovalent label moiety, wherein B is exclusive of any portion of the intercalation and label moieties.Preferably A is a 4-methylene-substituted psoralen moiety, and most preferably A is a 4'-methylene-substituted-4,5',8-trimethylpsoralen moeity and L is biotin.

Abstract: A radiant energy method and apparatus is used to determine a property such as thickness or weight per unit area of a material (14 or 40 or 170 or 238), e.g., a sheet, that is located or moving generally in a predetermined spatial relation to a first reference position (16a or 40a or 56a). A second reference position (22, 56 or 230) is defined. A sensor means (18 or 44; or 102, 112, 106 and 108; or 150, 154 and 158; or 214 and 216; or 236, 242 and 244) responds to a condition of the material. The relation of the sensor response to the material property is susceptible to change with changes in the distance relationship of the sensor means and one of the reference positions or the material. There is produced a distance response (26 or D.sub.2 (x) or 110 and 110 ' or .tau..sub.1 and .tau.'.sub.1 or D.sub.2 (.tau.) or D.sub.2 or 236, 236' or 258, 258') to changes in the distance from the sensor means to one of the reference positions. The distance response is systematically related (e.g.

Abstract: A non-contact optical gauging device in which a laser beam is deflected to produce a bidirectional scan. The beam is split; a measuring portion scans an object being inspected while the other portion scans a calibration reticle having alternating opaque and transparent bands. The alternating transmission and ocultation of the beam through the reticle is used to generate calibration pulses, each representing a predetermined increment of movement of the calibration beam. Ocultation of the measuring beam by the object being measured generates a signal which is used to control counting of the calibration pulses as an indication of the dimension being measured. Bidirectional averaging is employed to minimize errors due to object motion in the direction of beam scanning. Variations are disclosed in which two measuring beams and one or two calibration beams, are employed for measuring large objects or for dual axis measurement, the latter by orthogonal projection onto the object being measured.