Rotation and Color Properties of the Nucleus of Comet 2P/Encke

We present results from CCD observations of comet 2P/Encke acquired at Steward Observatory's 2.3m Bok Telescope on Kitt Peak obtained in Oct. 2002, when the comet was near aphelion. Rotational lightcurves in B, V and R-filters were acquired over two nights of observations, and analysed to study the physical and color properties of the nucleus. The average apparent R-filter magnitude across both nights corresponds to a mean effective radius of 3.95 +/- 0.06 km. The rotational lightcurve results in a nucleus axial ratio a/b >= 1.44 +/- 0.06 and semi-axes lengths of [3.60 +/- 0.09] x [5.20 +/- 0.13] km. Our data includes the first detailed time series multi-color measurements of a cometary nucleus, and significant color variations were seen. The average color indices across both nights are: (V-R) = 0.39 +/- 0.06 and (B-V) = 0.73 +/- 0.06 (R_mean = 19.76 +/- 0.03). We linked our data with the September 2002 data from Fernandez et al. (2005) - taken just 2-3 weeks before the current data set - and we show that a rotation period of 11.083 +/- 0.003hours works extrememly well for the combined data set.Comment: Accepted for publication in Icarus (Dec 2006). 27 page

Predicting uncertainty in sediment transport and landscape evolution - the influence of initial surface conditions

© 2015. Numerical landscape evolution models were initially developed to examine natural catchment hydrology and geomorphology and have become a common tool to examine geomorphic behaviour over a range of time and space scales. These models all use a digital elevation model (DEM) as a representation of the landscape surface and a significant issue is the quality and resolution of this surface. Here we focus on how subtle perturbations or roughness on the DEM surface can produce alternative model results. This study is carried out by randomly varying the elevations of the DEM surface and examining the effect on sediment transport rates and geomorphology for a proposed rehabilitation design for a post-mining landscape using multiple landscape realisations with increasing magnitudes of random changes. We show that an increasing magnitude of random surface variability does not appear to have any significant effect on sediment transport over millennial time scales. However, the random surface variability greatly changes the temporal pattern or delivery of sediment output. A significant finding is that all simulations at the end of the 10,000 year modelled period are geomorphologically similar and present a geomorphological equifinality. However, the individual patterns of erosion and deposition were different for repeat simulations with a different sequence of random perturbations. The alternative positions of random perturbations strongly influence local patterns of hillslope erosion and evolution together with the pattern and behaviour of deposition. The findings demonstrate the complex feedbacks that occur even within a simple modelled system

Neuraminidase Activity in \u3cem\u3eDiplococcus pneumoniae\u3c/em\u3e

Kelly, R. T. (Marquette University School of Medicine, Milwaukee, Wis.), D. Greiff, and S. Farmer. Neuraminidase activity in Diplococcus pneumoniae. J. Bacteriol. 91:601–603. 1966.—A method for the quantitation of neuraminidase in the presence of N-acetylneuraminic acid aldolase is described. The neuraminidase content of Diplococcus pneumoniae was found to be dependent on the media employed for growth; the highest enzyme activity per milligram of bacterial protein was obtained with Todd-Hewitt broth. Neuraminidase production was stimulated in D. pneumoniae by the addition of N-acetylneuraminlactose, N-acetylneuraminic acid, or N-acetylmannosamine to the growth medium. Three rough strains of D. pneumoniae, which were nonpathogenic for mice, lacked neuraminidase activity. Seven of 12 smooth strains contained neuraminidase; enzyme activity was not detected in the remaining 5 smooth strains. There was no correlation between the presence of neuraminidase activity and the capsular type or between neuraminidase production and animal virulence

Effect of Source of Pig, Housing System, and Receiving Diet on Performance of Purchased Feeder Pigs

An experiment was conducted to determine the effect of source of pig, housing system and receiving diet on performance of purchased feeder pigs. Pigs purchased from distant auction markets (DM) gained slower for the first 13 d post-arrival (P\u3c.01, trials 1 and 2) than pigs of similar size purchased from local, one-owner sources (LS)

Monoamine oxidase-A modulates apoptotic cell death induced by staurosporine in human neuroblastoma cells

Monoamine oxidases (MAOs) are mitochondrial enzymes which control the levels of neurotransmitters in the brain and dietary amines in peripheral tissues via oxidative deamination. MAO has also been implicated in cell signalling. In this study, we describe the MAO-A isoform as functional in apoptosis induced by staurosporine (STS) in human dopaminergic neuroblastoma cells (SH-SY5Y). Increased levels of MAO-A activity were induced by STS, accompanied by increased MAO-A protein and activation of the initiator of the intrinsic pathway, caspase 9, and the executioner caspase 3. MAO-A mRNA levels were unaffected by STS, suggesting that changes in MAO-A protein are due to post-transcriptional events. Two unrelated MAO-A inhibitors reduced caspase activation. STS treatment resulted in sustained activation of the mitogen-activated protein kinase pathway enzymes extracellular regulated kinase, c-jun terminal kinase and p38, and depletion of the anti-apoptotic protein Bcl-2. These changes were significantly reversed by MAO inhibition. Production of reactive oxygen species was increased following STS exposure, which was blocked by both MAO inhibition and the antioxidant N-acetylcysteine. Therefore our data provide evidence that MAO-A, through its production of reactive oxygen species as a by-product of its catalytic activity on the mitochondrial surface, is recruited by the cell to enhance apoptotic signalling

Bingham Dai, Adolf Storfer, and the tentative beginnings of psychoanalytic culture in China, 1935-1941.

This paper looks at the work of two figures who, while marginal to theoretical developments within the history of psychoanalysis, each briefly played an important role in the dissemination of analytical ideas in China, contributing to an early psychoanalytic culture there. Bingham Dai, a native of China, while studying for a PhD in sociology at Chicago, received instruction from Harry Stack Sullivan and a psychoanalytic training under Karen Horney's supervision. However, the neo-Freudian outlook with which this experience imbued him had its roots in an earlier encounter with his experiments in personality education first conducted on students in a Tientsin high school, and later in Shantung under the direction of the conservative Confucian scholar and reformer, Liang Shu Ming. These experiences convinced him that a less orthodox psychoanalytic perspective was what Chinese patients with psychological problems required. He returned in 1935 to teach medical psychology to doctors at Peking Union Medical College, taking a few into analysis and treating some patients. However, the Sino-Japanese war brought these activities to a close and he left in 1939, just a few months after the former Freud publisher and Viennese émigré, Adolf Storfer, arrived. Storfer set about publishing "Gelbe Post," a German language periodical replete with articles on psychoanalysis, linguistics and Chinese culture. But limited finances, severe competition from a rival publisher, plus his own ill health, forced him to abandon this in spite of the support offered him through the many contributors in the international psychoanalytic community whose articles he published. The paper concludes by considering the relative historiographic fate of the men upon whom subsequent scholarship has been very unevenly focused.published_or_final_versio

Rotation of Cometary Nuclei New Lightcurves and an Update of the Ensemble Properties of Jupiter-Family Comets

We report new lightcurves and phase functions for nine Jupiter-family comets (JFCs). They were observed in the period 2004-2015 with various ground telescopes as part of the Survey of Ensemble Physical Properties of Cometary Nuclei (SEPPCoN) as well as during devoted observing campaigns. We add to this a review of the properties of 35 JFCs with previously published rotation properties. The photometric time-series were obtained in Bessel R, Harris R and SDSS r' filters and were absolutely calibrated using stars from the Pan-STARRS survey. This specially-developed method allowed us to combine data sets taken at different epochs and instruments with absolute-calibration uncertainty down to 0.02 mag. We used the resulting time series to improve the rotation periods for comets 14P/Wolf, 47P/Ashbrook-Jackson, 94P/Russell, and 110P/Hartley 3 and to determine the rotation rates of comets 93P/Lovas and 162P/Siding-Spring for the first time. In addition to this, we determined the phase functions for seven of the examined comets and derived geometric albedos for eight of them. We confirm the known cut-off in bulk densities at $\sim$0.6 g $\mathrm{cm^{-3}}$ if JFCs are strengthless. Using the model of Davidsson (2001) for prolate ellipsoids with typical density and elongations, we conclude that none of the known JFCs require tensile strength larger than 10-25 Pa to remain stable against rotational instabilities. We find evidence for an increasing linear phase function coefficient with increasing geometric albedo. The median linear phase function coefficient for JFCs is 0.046 mag/deg and the median geometric albedo is 4.2 per cent.Comment: 38 pages, accepted for publication in MNRA

Interactions of asbestos-activated macrophages with an experimental fibrosarcoma

Supernatants from in vivo asbestos-activated macrophages failed to show any cytostatic activity against a syngeneic fibrosarcoma cell line in vitro. UICC chrysotile-induced peritoneal exudate cells also failed to demonstrate any growth inhibitory effect on the same cells in Winn assays of tumor growth. Mixing UICC crocidolite with inoculated tumor cells resulted in a dose-dependent inhibition of tumor growth; this could, however, be explained by a direct cytostatic effect on the tumor cells of high doses of crocidolite, which was observed in vitro