Abstract:
A bit retention apparatus for the use of retrieving the hammer bit in cases of shankage. The apparatus incorporates a dual sleeve design that fits over the chuck and the extended head section of the hammer bit. The first, “inner” sleeve has two or more ring pieces that fit onto the chuck and have the retention ring fitted into the lower section of the sleeve. The second, “outer” sleeve fits onto the chuck over the inner sleeve to provide protect to the inner sleeve while pulling the shanked bit out of the well bore. Attachment to the bit is accomplished by collars, knobs, or threads on the interior of the sleeves that correspond with holding bands, retention rings, or threads on the bit and chuck.
Abstract:
Normalization of experimental fragment patterns for nucleic acid polymers having putatively known sequences starts with obtaining at least one raw fragment pattern for the experimental sample. The raw fragment pattern represents the positions of a selected nucleic acid base within the polymer as a function of migration time or distance. This raw fragment pattern is conditioned using conventional baseline correction and noise reduction technique to yield a clean fragment pattern. The clean fragment pattern is then evaluated to determine one or more “normalization coefficients.” These normalization coefficients reflect the displacement, stretching or shrinking, and rate of stretching or shrinking of the clean fragment, or segments thereof, which are necessary to obtain a suitably high degree of correlation between the clean fragment pattern and a standard fragment pattern which represents the positions of the selected nucleic acid base within a standard polymer actually having the known sequence as a function of migration time or distance. The normalization coefficients are then applied to the clean fragment pattern to produce a normalized fragment pattern which is used for base-calling in a conventional manner. This method may be implemented in an apparatus comprising a computer processor programmed to determine normalization coefficients for an experimental fragment pattern. This computer may be separate from the electrophoresis apparatus, or part of an integrated unit.
Abstract:
Normalization of experimental fragment patterns for nucleic acid polymers having putatively known sequences starts with obtaining at least one raw fragment pattern for the experimental sample. The raw fragment pattern represents the positions of a selected nucleic acid base within the polymer as a function of migration time or distance. This raw fragment pattern is conditioned using conventional baseline correction and noise reduction technique to yield a clean fragment pattern. The clean fragment pattern is then evaluated to determine one or more "normalization coefficients." These normalization coefficients reflect the displacement, stretching or shrinking, and rate of stretching or shrinking of the clean fragment, or segments thereof, which are necessary to obtain a suitably high degree of correlation between the clean fragment pattern and a standard fragment pattern which represents the positions of the selected nucleic acid base within a standard polymer actually having the known sequence as a function of migration time or distance. The normalization coefficients are then applied to the clean fragment pattern to produce a normalized fragment pattern which is used for base-calling in a conventional manner. This method may be implemented in an apparatus comprising a computer processor programmed to determine normalization coefficients for an experimental fragment pattern. This computer may be separate from the electrophoresis apparatus, or part of an integrated unit.
Abstract:
A virtual DNA sequencer combines a plurality of individual DNA sequencers. Samples of DNA or other nucleic acid from subjects are prepared and allocated in real time to particular lanes or sets of lanes in electrophoresis plates of the individual sequencers, with records kept of the allocations. The data resulting from the electrophoresis runs is collected and collated according to the identities of the subjects. The individual sequencers are networked, and each individual sequencer is preferably equipped with a data buffer large enough to accommodate all or substantially all of a data run, thus protecting the virtual sequencer from loss of valuable data in the event that the network is disrupted for some portion of the time of the data run. In this way, a plurality of sequencers is virtually the same as a single sequencer with a very large number of tracks each of which can run for a much longer sequencing run than an individual sequencer.
Abstract:
A nonwoven fibrous structure and process for forming it, which is an interconnecting web of polyolefin filaments having filament widths greater than about 1 micrometer which are further interconnected with webs of smaller polyolefin filaments having filament widths less than about 1 micrometer, wherein the smaller polyolefin filaments comprise a majority of all filaments.