Abstract: Sample processing methods that utilize a graphitised carbon matrix are useful for determining the relative amounts polyhalogenated biphenyls (PHBs), polyhalogenated dibenzofurans (PHDFs), and polyhalogenated dibenzo-p-dioxins (PHDDs) in a mixture of polyhalogenated diaromatic hydrocarbons (PHDHs). The methods are particularly useful when used in conjunction with cell-based assays for determining the toxicity of PHDH compounds.

Abstract: Sample processing methods that utilize a graphitised carbon matrix are useful for determining the relative amounts polyhalogenated biphenyis (PHBs), polyhalogenated dibenzofurans (PHDFs), and polyhalogenated dibenzo-p-dioxins (PHDDs) in a mixture of polyhalogenated diaromatic hydrocarbons (PHDHs). The methods are particularly useful when used in conjunction with cell-based assays for determining the toxicity of PHDH compounds.

Abstract: A recombinant cell line deposited at the American Type Culture Collection under ATCC accession number CRL-12286, also known as the mouse H1L1.1 cell line, has been made by using genetic engineering techniques for inserting dioxin responsive elements upstream of a luciferase reporter gene, and then, transfecting the resultant recombinant expression plasmid, identified as pGudLuc1.1, into mouse hepatoma cells. The mouse H1L1.1 cell line is useful in a method for the quantitative analysis of polyaromatic hydrocarbons in samples.

Abstract: In a communication system for transmitting information over a dispersive link, a transmitted message is assembled to contain alternately arranged known and unknown pluralities of data symbols. At the transmitter, the known data symbols may be produced by a maximal length PN sequence generator, with an identical generator being provided at the receiver for reproducing the known symbol sequences to enable data recovery to be achieved. In the received signal processing equipment, the received message is subjected to a prescribed data recovery algorithm containing a transversal filter function and a data estimate refinement scheme which takes advantage of the a priori knowledge of data symbols of those portions of the transmitted message between which unknown data symbols are located. A transmitted message contains a plurality of successive frame, each frame containing N known data symbols followed by M unknown data symbols.

Abstract: A variable speed drive for a riding lawn mower or the like has a double pulley variable speed sheave assembly coupled between a driving pulley and a driven pulley by first and second V-belts, respectively. The sheave assembly is carried at one end of a bell crank which is centrally pivoted to one end of a pivot arm. The pivot arm is pivotally connected to the vehicle frame and is biased to urge the sheave assembly toward an operating position with the belts under driving tension. A mechanical control linkage is connected to the other end of the bell crank, and is operable to shift the sheave assembly with respect to the driving and driven pulley to alter the sheave assembly drive ratio in a manner such that belt tension varies with variations in operating speed. The control linkage is operable to move the sheave assembly between a stopped position with both belts declutched and a range of low to high speed operating positions, and is springably biased to urge the sheave assembly toward said stopped position.

Abstract: A variable speed drive for a riding lawn mower or the like has a double pulley variable speed sheave assembly coupled between a driving pulley and a driven pulley by first and second V-belts, respectively. A mechanical control linkage is operable to shift the sheave assembly along the cam profile of a cam arm from a stopped position with both belts declutched to a range of low to high speed positions with the belts drivingly engaged. Said control linkage is springably biased to urge the sheave assembly toward the stopped position. The cam arm is also springably biased generally away from the driving and driven pulleys to maintain the belts under driving tension throughout the range of low to high speed positions in a manner such that belt tension varies with variations in operating speed.

Abstract: A variable speed drive for a riding lawn mower or the like has a double pulley variable speed sheave assembly coupled between a driving pulley and a driven pulley by first and second V-belts, respectively. The sheave assembly is carried on a pivot arm pivotally mounted on a frame for the vehicle. A mechanical control linkage connected to the pivot arm is operable to shift the sheave assembly with respect to the driving and driven pulleys from a stopped position with both belts declutched through a range of low to high speed drive positions with the belts drivingly engaged. An idler pulley is carried on a spring lever assembly for engaging and variably tensioning one of the belts throughout said range of speed positions to place the belts under variable driving tension in accordance with operating speed.

Abstract: A scale which has a frame that is freely movable about the floor defined by a base having forward and aft ends and a pair of spaced-apart upright posts connected to the base and disposed adjacent the aft end thereof. The weighing mechanism includes a carriage that is vertically movable along the posts and which has a pair of horizontal, forwardly projecting arms that support a weigh-board in its horizontal position. The weigh-board is pivotally attached to one of the arms and means is provided for releasably locking the weigh-board in its upright storage position. A guardrail is rigidly secured to the frame and positioned immediately forward of the carriage so that the scale, with the weigh-board in its horizontal position, can be pushed over a hospital bed for transferring a patient onto or from the weigh-board while preventing any contact between any portion of the weighing mechanism and the bed to prevent inaccurate weight measurements.