2,530 research outputs found
The Surface Brightness Fluctuations and Globular Cluster Populations of M87 and its Companions
Using the surface brightness fluctuations in HST WFPC-2 images, we determine
that M87, NGC 4486B, and NGC 4478 are all at a distance of ~16 Mpc, while NGC
4476 lies in the background at ~21 Mpc. We also examine the globular clusters
of M87 using archived HST fields. We detect the bimodal color distribution, and
find that the amplitude of the red peak relative to the blue peak is greatest
near the center. This feature is in good agreement with the merger model of
elliptical galaxy formation, where some of the clusters originated in
progenitor galaxies while other formed during mergers.Comment: 5 pages, 2 figure
Inhibitor regulation of tissue kallikrein activity in the synovial fluid of patients with rheumatoid athritis
Tissue kallikrein (TK) and 1-antitrypsin (AT)/TK complexes can be detected in SF from patients with RA if components of the fluids which interfere with the detection of TK are removed. 2-Macroglobulin (2-M) in SF was demonstrated to contain trapped proteases which were still active in amidase assays. Removal of 2-M from RA SF reduced their amidase activity. However, at least some of the remaining activity was due to TK because it was soya bean trypsin inhibitor resistant and trasylol sensitive and was partly removed by affinity chromatography on anti-TK sepharose. Removal of RF from the fluids reduced the values obtained for TK levels by ELISA. Addition of SF to human urinary kallikrein (HUK) considerably reduced the levels of TK detected suggesting the presence of a TK ELISA inhibitor in the fluids. Removal of components of >300 kDa from SF markedly reduced the TK ELISA inhibitory activity and increased the values for both the TK and l-AT/TK levels in fluids as measured by ELISA. It is considered this novel inhibitor does not bind to the active site of TK but rather binds to the site reactive with anti-TK antibodies
Vertical Distribution, Persistence, and Activity of Entomopathogenic Nematodes (Nematoda: Heterorhabditidae and Steinernematidae) in Alfalfa Snout Beetle- (Coleoptera: Curculionidae) Infested Fields
The vertical movement, persistence, and activity of four isolates of entomopathogenic nematodes, Heterorhabditis bacteriophora Poinar (Oswego), Heterorhabditis bacteriophora Poinar (NC), Steinernema carpocapsae (Weiser) (NY001),and an undescribed Steinernema species (NY008-2E), were evaluated for 24 mo at field locations in northern New York. Nematodes were released into three alfalfa fields naturally infested with alfalfa snout beetle, Otiorhynchus ligustici (L.). Each field differed in soil type and soil textural composition: silt loam, sandy loam, and loamy sand. Nematodes were recovered from soil using trap insects, Galleria mellonella larvae, and their vertical distribution was monitored at 5-cm intervals to depths of 20 cm for Steinernena species and 35 cm for Heterorhabditis species. All nematodes persisted (no significant reduction in percentage of infection of G. mellonella) for 6 mo after the initial application in all soil types. However, by the end of the second growing season (17 mo after application), all nematodes showed significant reductions in infection rates of G. mellonella except H. bacteriophora (Oswego) which showed high levels of infection for 24 mo. Nematode vertical movement was affected by soil type and varied by isolate. S. carpocapsae (NY00l)and Steinernema sp. (NY008-2E) remained primarily in soil depths <15 cm, whereas both heterorhabditids dispersed to soil depths of 35 cm. Vertical movement of H. bacteriophera (Oswego) was greatest in loamy sand and vertical movement of Steinernema sp. (NY008-2E) was greatest in sandy loam. Percentage of infection of G. mellonella by H. bacteriophora (Oswego) and S. carpocapsae (NY00l)was significantly correlated with rising soil temperatures in early spring. H. bacteriophora (Oswego) and S. carpocapsae (NYOOl)infected G. mellonella larvae in the field at soil temperatures between 15 and 18°C. Steinernema sp. (NY008-2E)infected G. mellonella larvae in the field at soil temperatures between 13 and 15°
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