Testing of turbulent seals for rotordynamic coefficients

A facility has been developed for dynamic testing of straight and convergent tapered seals with the capability of measuring the radial and tangential force components which result from a circular centered orbit. The test apparatus causes the seal journal to execute small-eccentricity centered circular orbits within its clearance circle. Dynamic measurements are made and recorded of the seal displacement-vector components, and of the pressure field. The pressure field is integrated to yield seal tangential and radial reaction-force components. Representative test data are provided and discussed for straight seals

A high-Reynolds-number seal test facility: Facility description and preliminary test data

A facility has been developed for testing the leakage and rotordynamic characteristics of interstage-seal configurations for the HPFTP (High Pressure Fuel Turbopump) of the SSME (Space Shuttle Main Engine). Axial Reynolds numbers on the order of 400,000 are realized in the test facility by using a Dupont freon fluid called Halon (CBrF3). The kinematic viscosity of Halon is of the same order as the liquid hydrogen used in the HPFTP. Initial testing has focused on the current flight configurations (a three-segment, stepped unit) and a convergent-taper candidate

Whitman and Worcester

Uses a recently discovered copy of Jospeh E. Worcester\u27s Universal and Critical Dictionary of the English Language (1849) signed by Whitman to argue for the likelihood of Whitman\u27s use of the book in his notebooks on language

AAV-MEDIATED GENE TRANSFER TO MODELS OF MUSCULAR DYSTROPHY: INSIGHTS INTO ASSEMBLY OF MULTI-SUBUNIT MEMBRANE PROTEINS.

The sarcoglycanopathies are a subset of the limb girdle muscular dystrophies (LGMD) caused by mutations in the sarcoglycan genes (alpha, beta, gamma and delta). In collaborative studies, delta-sarcoglycan was delivered to deficient hamsters using a recombinant adeno-associated virus (AAV), which rescued muscle biochemically, histologically, and functionally. Murine knockouts for the other sarcoglycans permitted us to pursue AAV-mediated gene delivery. AAV-mediated gene delivery of beta-sarcoglycan to deficient mice provided long-term biochemical and histological rescue. AAV-mediated gene delivery of alpha-sarcoglycan to deficient mice showed initial rescue of biochemical and histological defects, although expression was not persistent. Severe Combined Immune-Deficient (SCID) mouse studies indicated that alpha-sarcoglycan over-expression leads to cytotoxicity. The apparent cytotoxicity can be interpreted with emerging models of sarcoglycan complex assembly. These studies show that AAV-mediated delivery of even closely related proteins can lead to different outcomes, and aspects of protein biochemistry can alter efficacy of gene delivery.Inherited muscle disorders typically have defined primary biochemical defects. However, there are likely secondary responses that mitigate gene delivery success. To dissect such variables, we studied the immunostimulatory properties of dystrophic muscle. We hypothesized that immune cell infiltrate accompanying degeneration/regeneration could be immunostimulatory, which could elicit an immune response to delivered transgenes, hampering the success of gene delivery. To study this, we tested antibody response to and persistence of, beta-galactosidase in normal and dystrophic muscle. Consistent with our hypothesis, dystrophic muscle showed increased immune surveillance and recognition of beta-galactosidase, evidenced by antibody titers and clearance of transduced cells. Furthermore, biochemical rescue of the dystrophy quenched the immune response. This indicated that dystrophic muscle is more prone to immune responses and that aspects of tissue pathology influence the persistence and efficacy of gene delivery. Our results suggest that full biochemical rescue will attenuate immunostimulatory effects. We also address a hurdle facing AAV-mediated gene therapy; namely, delivery methods. We developed an injection manifold, which was used to safely, accurately, and consistently deliver genes to 20 mm2 regions of muscle. Taken together, these results more clearly define barriers to gene delivery. Future research will finely tune regulation of transgenes and enable full rescue of biochemical defects

When Can the Baseball Writers For the Hall of Fame Consider Cheating Through PED Use, Or Not?

When the 2013 MLB Hall of Fame Ballot was released this past November, the heated discussion began about which controversial candidates, if any at all, would be inducted into Cooperstown (HOF). while isolated athletes have come up in previous years, this year represents a first real tension between the modern ear of baseball - the steroid era - and traditional standards for admission into the Hall. The 537 baseball writers are, and should be, entrusted to weigh cheating and use of PEDs against the HOF\u27s criteria of character, sportsmanship and upholding the integrity of the game. These writers each will struggle, however, with a preliminary question that falls outside of their expertise: under which circumstances may a HOF voter consider, at all, a candidate\u27s connection to cheating and performance-enhancing drugs

When Can the Baseball Writers For the Hall of Fame Consider Cheating Through PED Use, Or Not?

When the 2013 MLB Hall of Fame Ballot was released this past November, the heated discussion began about which controversial candidates, if any at all, would be inducted into Cooperstown (HOF). while isolated athletes have come up in previous years, this year represents a first real tension between the modern ear of baseball - the steroid era - and traditional standards for admission into the Hall. The 537 baseball writers are, and should be, entrusted to weigh cheating and use of PEDs against the HOF\u27s criteria of character, sportsmanship and upholding the integrity of the game. These writers each will struggle, however, with a preliminary question that falls outside of their expertise: under which circumstances may a HOF voter consider, at all, a candidate\u27s connection to cheating and performance-enhancing drugs

Reading instruction in first-grade classrooms: Do basals control teachers?

This study describes first-grade teachers beliefs and practices about reading instruction. Drawing from interview and observational data, 16 teachers from four districts were placed on a continuum from skills-based to literature-based in relationship to their use of the basal. Only 2 teachers were found to rely solely on the basal, while 3 teachers enhanced the basal with literature, and 4 teachers used only literature in their reading instruction. Six teachers enhanced their basal use with additional skills and 1 teacher relied on skills only in her reading instruction. This diversity\u27 of teaching beliefs and practices was corroborated by questionnaire data from a larger sample of teachers. Next, a framework developed by Belenky, Clinchy, Goldberger, and Tarule (1986) was used to categorize teachers\u27 ways of knowing. The findings showed 1 teacher to be a silent knower, 6 were received knowers, 1 was a subjective knower, 7 were procedural knowers, and 1 was a connected knower. Results challenge Shannon\u27s (1987) hypothesis that basals deskill teachers while supporting Sosniak and Stodolskv\u27s (1993) view that teachers are more autonomous in their use of textbook materials