Magnetic structure of free cobalt clusters studied with Stern-Gerlach deflection experiments

We have studied the magnetic properties of free cobalt clusters in two semi-independent Stern-Gerlach deflection experiments at temperatures between 60 and 307 K. We find that clusters consisting of 13 to 200 cobalt atoms exhibit behavior that is entirely consistent with superparamagnetism, though complicated by finite-system fluctuations in cluster temperature. By fitting the data to the Langevin function, we report magnetic moments per atom for each cobalt cluster size and compare the results of our two measurements and all those performed previously. In addition to a gradual decrease in moment per atom with increasing size, there are oscillations that appear to be caused by geometrical shell structure. We discuss our observations in light of the two competing models for Langevin-like magnetization behavior in free clusters, superparamagnetism and adiabatic magnetization, and conclude that the evidence strongly supports the superparamagnetic model

Microfauna of the Colorado Shale in the Sunburst Dome Area, Montana

It has been hoped that a micropaleontological study of the shales of the Upper Cretaceous Colorado Group in northern Montana would reveal certain faunal zones which would serve as markers in an otherwise drab, undifferentiated, 1800 feet of grey, fissile shale. This paper presents the results of a study of the microfauna in certain samples from this shale in the Sunburst Dome area north of Shelby, Montana

DWM07 global empirical model of upper thermospheric storm-induced disturbance winds

We present a global empirical disturbance wind model (DWM07) that represents average geospace-storm-induced perturbations of upper thermospheric (200-600 km altitude) neutral winds. DWM07 depends on the following three parameters: magnetic latitude, magnetic local time, and the 3-h Kp geomagnetic activity index. The latitude and local time dependences are represented by vector spherical harmonic functions ( up to degree 10 in latitude and order 3 in local time), and the Kp dependence is represented by quadratic B-splines. DWM07 is the storm time thermospheric component of the new Horizontal Wind Model (HWM07), which is described in a companion paper. DWM07 is based on data from the Wind Imaging Interferometer on board the Upper Atmosphere Research Satellite, the Wind and Temperature Spectrometer on board Dynamics Explorer 2, and seven ground-based Fabry-Perot interferometers. The perturbation winds derived from the three data sets are in good mutual agreement under most conditions, and the model captures most of the climatological variations evident in the data

Relative concentrations of haemostatic factors and cytokines in solvent/detergent-treated and fresh-frozen plasma

Background Indications, efficacy, and safety of plasma products are highly debated. We compared the concentrations of haemostatic proteins and cytokines in solvent/detergent-treated plasma (SDP) and fresh-frozen plasma (FFP). Methods Concentrations of the following parameters were measured in 25 SDP and FFP samples: fibrinogen (FBG), factor (F) II, F V, F VII, F VIII, F IX, F X, F XIII, von Willebrand factor (vWF), D-Dimers, ADAMTS-13 protease, tumour necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, IL-8, and IL-10. Results Mean FBG concentrations in SDP and FFP were similar, but in FFP, the range was larger than in SDP (P<0.01). Mean F II, F VII, F VIII, F IX, and F XIII levels did not differ significantly. Higher concentrations of F V (P<0.01), F X (P<0.05), vWF (P<0.01), and ADAMTS-13 (P<0.01) were found in FFP. With the exception of F VIII and F IX, the range of concentrations for all of these factors was smaller (P<0.05) in SDP than in FFP. Concentrations of TNF-α, IL-8, and IL-10 (all P<0.01) were higher in FFP than in SDP, again with a higher variability and thus larger ranges (P<0.01). Conclusions Coagulation factor content is similar for SDP and FFP, with notable exceptions of less F V, vWF, and ADAMTS-13 in SDP. Cytokine concentrations (TNFα, IL-8, and IL-10) were significantly higher in FFP. The clinical relevance of these findings needs to be established in outcome studie

An Instrument for Lunar Surface Chemical Analysis

Instrument for lunar surface chemical analysis that uses interactions with matter of monoenergetic alpha particle