Abstract: A lifting device that has a carriage supported by a chain which passes over a sprocket-wheel disposed to rotate about an axis and features an equalizer system that reduces variations in the measurement, by a load cell, of a load supported by the carriage. To further enhance the accuracy of the measurement, the load cell is designed to accurately measure the load placed thereon independent of the position of the load on the cell. The equalizer system consists of providing the chain and the sprocket-wheel with the dimensions necessary so that each link of the chain subtends a predetermined portion of the sprocket-wheel's circumference.

Abstract: A method for coupling DNA to a glass substrate by aminating the glass substrate with an aminosilane, reacting DNA with a carbodiimide/imidazole solution to create a 5'-phosphorimidazolide, and reacting the aminated glass substrate and phosphorimidazolide to couple the DNA to the substrate.

Abstract: A zero power fuse circuit includes a latch means having two inputs, a first input being latched to ground and a second input being latched to V.sub.cc. The latch means is triggered either by a momentary contact of the first input to ground or by the momentary contact of the second input to V.sub.cc. A first embodiment includes two fuse element/capacitor pairs each coupled to one of the two inputs of the latch means. A second embodiment includes a pull-up transistor and a fuse element/capacitor pair, coupled to the first and second inputs respectively. A third embodiment includes a pull-down transistor and a fuse element/capacitor pair respectively coupled to the second and first inputs of the latch means.

Abstract: A capillary electrophoresis separation matrix for single-stranded nucleic acids, along with methods for using and preparing the matrix, are disclosed. The separation matrix provides denaturing conditions and contains hydroxyethyl cellulose (HEC) in combination with urea, and preferably also includes formamide. The separation matrix may be used for DNA sizing and sequencing applications and provides a single-base resolution to approximately 500 base pairs. The separation matrix is inexpensive, easy to prepare, requires no polymerization steps, and is of low enough viscosity to be pumped easily into and out of capillary tubes for electrophoresis. The low viscosity allows for high throughput of samples and reuse of the capillary tubes for numerous separations.

Abstract: An in-line roller skate includes a transducer portion capable of sensing the rotary movement of at least one wheel on the roller skate and transmitting information concerning the same to a receiver worn on a user's wrist. In the preferred embodiment, the transducer portion includes a magnet attached to one of the plurality of wheels and a sensor positioned in a shoe portion to detect the magnet and produce electrical pulses containing information corresponding to the angular velocity of the wheel. The transducer portion also includes a micro-controller, a transmitter and an antenna. The micro-controller creates a digital data stream containing information corresponding to the angular velocity of the wheel, which is then modulated onto a carrier wave produced by the transmitter. The transmitter transmits the coded signals to the receiver. The receiver demodulates the carrier wave, reproducing the digital data stream.

Abstract: A helical load cell is disclosed which is capable of accurately measuring axially applied forces, whether the force is applied axially within the diameter of the helical coil or outside of the coil diameter. A pair of strain gage modules are disposed on diametrically opposed surfaces of the coil. Each module includes a pair of transducer elements disposed orthogonally with respect to each other and at forty-five degrees relative to a neutral axis of the coil. The modules are coupled in an additive bridge circuit arrangement. In one embodiment, the modules are disposed along the outside diameter of the coil. In another embodiment, the modules are disposed along the inside diameter of the coil. In yet another embodiment, the modules are dispose on the upper or lower surface of the coil. In yet another embodiment, a second pair of strain gage modules is provided and coupled in a subtractive bridge circuit. The second pair of modules provides information as to the location of the applied load.

Abstract: The present invention is a single-ended Class A gain stage amplifier consisting of an active current source. A feedback path from an output node of the amplifier senses the direction and magnitude of the current going through a load coupled to the output node. The feedback path varies the output of the active current source in accordance with the sensed load current. By so doing, the efficiency of the amplifier of the present invention can be doubled as compared to prior art amplifiers operating in Class A mode. In addition, the present invention amplifier exhibits lower signal distortion.

Abstract: A digital signal processing system for executing instructions, including a program memory which stores the instructions and a program control unit for receiving and processing a sequence of the instructions to generate control signals for controlling operation of the system, and a loop circuit for use in such a program control unit. The loop circuit controls execution of a loop (preferably a nested loop) of a sequence of the instructions. Preferably, the loop circuit includes loop registers for storing loop start and end addresses and loop count values, and logic circuitry for implementing loops (including nested loops) in response to the addresses and count values in the loop registers. The loop circuit is initialized by loading appropriate addresses and values into the loop registers.

Abstract: The present invention relates to a substrate for ball-grid arrays. Bond sites are arranged around a die-attach region of the substrate. Signal traces connect the bond sites to vias disposed on the substrate, thus providing an electrical path between both sides of the substrate. Solder balls (solder bumps) are disposed on the other side of the substrate and arranged in a grid-like pattern. The generally linearly-arranged bond sites are sequentially numbered, as is the grid-like arrangement of solder balls. In a preferred embodiment, the bond sites are used only for carrying signals to and from the semiconductor die. In addition, only the solder bumps used for carrying signals are sequentially numbered. In another embodiment of the invention, some of the bond sites may be used for utilities such as ground and power. Such utility bond sites are not numbered. Likewise, utility solder balls are not numbered. The signal bond sites are coupled to vias by signal traces.

Abstract: A coupling member is disclosed for connecting together adjacent hanging file folders. An elongate member includes a flat surface for attachment to a folder. A longitudinally formed slot is formed along the full length of the elongate member and positioned to receive the lip of the opening of an adjacent folder. In a preferred embodiment, the slot is defined by two spaced-apart surfaces which extend into the interior region of the elongate member. The interior region may be solid or may be partially or fully hollow. The elongate member has any one of a number of cross-sectional profiles, including semi-circular, rectilinear, triangular and concave shaped profiles. In another embodiment of the present invention, the coupling member is integrally formed with a hanging file folder. In a preferred variation, the coupling member is formed with hanging means such as tangs to assist in hanging the folder.

Abstract: A semiconductor die attach arrangement which provides an increase in signal availability to and from the die without compromising the physical integrity of signal traces and integrity of the conducted signal. In a preferred embodiment, a circuit board includes a die-attach region surrounded by a boundary line that is spaced apart from the die-attach region, thereby defining an intermediate region which surrounds the die-attach region. Bond sites are arranged along the boundary line. In one embodiment, the bond sites are first trace ends of a plurality of signal traces, some of the signal traces extending in an outward direction away from the die-attach region into a signal trace region, and some of the signal traces being directed within the intermediate region. Signal vias are formed in both the signal trace region and the intermediate region, and are electrically coupled to the signal traces at second trace ends of the signal traces.

Abstract: A particle counter including a modulator to allow electronically determining calibration. The modulator is connected to a driving circuit of a source of light to cause the light to emit a beam of a constant amplitude, representing at least one particle of predefined size. Light transmitted along an optical axis changes in intensity in response to a signal produced by the modulator. A detector is positioned to sense the change in intensity to produce signals proportional to the light sensed. A displaying device, such as a pulse height analyzer, is in electrical communication to receive the signals produced by the detector to quantitatively display the change in intensity of the light.

Abstract: A method for calibrating topographic instruments, operating at sub-micrometer resolution levels, includes providing a calibration standard having a known one-dimensional power spectral density function. A roughness is calculated from the known one dimensional power spectral density function in relation to an atomic scale topographic dimension, .increment.z.sub.i. The roughness of the calibration standard is measured by detecting light scattering therefrom and computing an isotropic power spectral density curve over the effective spatial bandwidth of the topographic instrument being calibrated. The measured roughness is then compared against the calculated roughness to determine whether the two values of roughness coincide.