Tuft

Abstract: The two-dimensional flow interaction between the primary flow and the secondary flow (often called an electric wind or ionic wind) in the wire-duct electrostatic precipitator (ESP) has been investigated theoretically and experimentally in the past. However, the analysis was limited to the two-dimensional, which is acceptable only for the positive polarity and small tuft spacing. The negative corona, commonly used for the industrial ESPs, generates tufts along the corona wire and the point coronas on the discharge wire and requires three-dimensional analysis. Three-dimensional electric field and space-charge density distributions, and the flow interaction between the primary flow and secondary flow, i.e., electrohydrodynamics were investigated. The computational results show that the secondary flow distribution consists of a donut-shaped ring from each tuft or corona point, which was predicted by the first author 16 years ago. When the primary flow exists, a pair of spiral rings, like Goertler vortices, is formed in the direction of the primary flow. The flow interaction was described using dimensionless number N/sub EHD/, which is the ratio of the ionic wind velocity to the primary flow velocity. The effects of particle motion in the electrohydrodynamic field in the tuft/point corona ESPs are discussed.

Abstract: An apparatus and method for cleaning surfaces and crevices of teeth wherein at least one tuft of filaments is rotated in a controlled reciprocating manner whereby the tuft is rotated a number of revolutionsin one direction and then rotated the same number of revolutions in the opposite direction. An alternative embodiment comprises a plurality of tufts of filaments, each of which is rotated in a controlled reciprocating fashion about its own central axis. Furthermore, immediately adjacent tufts are contrarotated. Each tuft is rotated about its own central axis, and placed in contact with the teeth whereby the filaments develop a twisting action dynamically and serially progressing from the base of each tuft to the opposite free ends of the filaments. The plurality of tufts are positioned in two parallel rows, each of which has adjacent tufts staggered with respect to each other.

Abstract: This paper explores in detail new image enhancement techniques for assessing tuft geometry and concomitant appearance changes in new and worn carpets. Using im proved algorithms and more advanced tuft geometry, saxony tufted carpets of nylon and polyester BCF yams are capable of being extensively and reliably characterized as to texture and changes in appearance with laboratory or floor wear. While still using a relatively low resolution grey level imaging system, the newly developed al gorithms demonstrate how tuft size distribution, number of tufts, evenness of tuft spatial distribution, and aspect ratio (shape factor) of tufts can be objectively measured. Statistical analysis confirms that customary wear levels, and their visual appearance change in carpet, can be separated and correctly grouped by these new techniques. Some limitations of these and other texture-sensitive image analysis techniques are also discussed.

Abstract: Tuft cells are a rare chemosensory lineage that coordinates immune and neural responses to foreign pathogens in mucosal tissues1. Recent studies have also revealed tuft-cell-like human tumours2,3, particularly as a variant of small-cell lung cancer. Both normal and neoplastic tuft cells share a genetic requirement for the transcription factor POU2F3 (refs. 2,4), although the transcriptional mechanisms that generate this cell type are poorly understood. Here we show that binding of POU2F3 to the uncharacterized proteins C11orf53 and COLCA2 (renamed here OCA-T1/POU2AF2 and OCA-T2/POU2AF3, respectively) is critical in the tuft cell lineage. OCA-T1 and OCA-T2 are paralogues of the B-cell-specific coactivator OCA-B; all three proteins are encoded in a gene cluster and contain a conserved peptide that binds to class II POU transcription factors and a DNA octamer motif in a bivalent manner. We demonstrate that binding between POU2F3 and OCA-T1 or OCA-T2 is essential in tuft-cell-like small-cell lung cancer. Moreover, we generated OCA-T1-deficient mice, which are viable but lack tuft cells in several mucosal tissues. These findings reveal that the POU2F3-OCA-T complex is the master regulator of tuft cell identity and a molecular vulnerability of tuft-cell-like small-cell lung cancer.