A study of the temporal changes recorded by ERTS and their geological significance

The temporal changes that are recorded by ERTS were evaluated for an area around Bathurst Inlet in the North West Territories. The seasons represented by the images included: early winter, spring, early summer, summer, and fall. Numerous surface characteristics (vegetation, drainage patterns, surface texture, lineament systems and topographic relief, etc.) were used to relate the change in observable features with the different seasons. It was found that the time of year when an observation is made has a strong control over the amount and type of information that can be derived by an experienced interpreter. It was concluded that a detailed study of temporal changes is an important part of any ERTS interpretation for geology

Propfan experimental data analysis

A data reduction method, which is consistent with the performance prediction methods used for analysis of new aircraft designs, is defined and compared to the method currently used by NASA using data obtained from an Ames Res. Center 11 foot transonic wind tunnel test. Pressure and flow visualization data from the Ames test for both the powered straight underwing nacelle, and an unpowered contoured overwing nacelle installation is used to determine the flow phenomena present for a wind mounted turboprop installation. The test data is compared to analytic methods, showing the analytic methods to be suitable for design and analysis of new configurations. The data analysis indicated that designs with zero interference drag levels are achieveable with proper wind and nacelle tailoring. A new overwing contoured nacelle design and a modification to the wing leading edge extension for the current wind tunnel model design are evaluated. Hardware constraints of the current model parts prevent obtaining any significant performance improvement due to a modified nacelle contouring. A new aspect ratio wing design for an up outboard rotation turboprop installation is defined, and an advanced contoured nacelle is provided

Description of an experimental (hydrogen peroxide) rocket system and its use in measuring aileron and rudder effectiveness of a light airplane

A hydrogen peroxide fueled rocket system, which is to be used as a research tool in flight studies of stall and spin maneuvers, was installed on a light, four place general aviation airplane. The pilot controlled rocket system produces moments about either the roll or the yaw body axis to augment or oppose the aerodynamic forces and inertial moments acting on the airplane during various flight maneuvers, including the spin. These controlled moments of a known magnitude can be used in various ways to help analyze and interpret the importance of the various factors which influence airplane maneuvers. The rocket system and its installation in the airplane are described, and the results of flight rests used to measure rudder and aileron effectiveness at airspeeds above the stall are presented. These tests also serve to demonstrate the operational readiness of the rocket system for future research operations

Spectral Models of Convection-Dominated Accretion Flows

For small values of the dimensionless viscosity parameter, namely $\alpha\lesssim 0.1$, the dynamics of non-radiating accretion flows is dominated by convection; convection strongly suppresses the accretion of matter onto the central object and transports a luminosity $\sim 10^{-3}-10^{-2} \dot M c^2$ from small to large radii in the flow. A fraction of this convective luminosity is likely to be radiated at large radii via thermal bremsstrahlung emission. We show that this leads to a correlation between the frequency of maximal bremsstrahlung emission and the luminosity of the source, $\nu_{\rm peak} \propto L^{2/3}$. Accreting black holes with X-ray luminosities $10^{-4} L_{Edd}\gtrsim L_X(0.5-10{\rm keV}) \gtrsim 10^{-7}L_{Edd}$ are expected to have hard X-ray spectra, with photon indices $\Gamma\sim2$, and sources with $L_X\lesssim 10^{-9}L_{Edd}$ are expected to have soft spectra, with $\Gamma\sim3.5$. This is testable with {\it Chandra} and {\it XMM}.Comment: final version accepted by ApJ; significant modifications from previous versio

Why is Family Medicine Different?

An understanding of the role and function of Family Medicine in the healthcare system can provide important insights for Enterprise Architecture. It is often stated that the thought process utilized by Family Medicine physicians is different from that of specialty physicians, but heretofore there has been little or no analysis of what that difference is. This article examines that difference from the perspective of the complex adaptive system that is healthcare today, and shows how it is that Family Medicine physicians perform the vital function of decreasing the entropy or disorder in the patient care system via decision loops, as opposed to the decision trees of linear or classical logic. The generalist function of Family Medicine physicians results in the integration and coordination of the various specialty functions in healthcare

B cells are capable of independently eliciting rapid reactivation of encephalitogenic CD4 T cells in a murine model of multiple sclerosis

<div><p>Recent success with B cell depletion therapies has revitalized efforts to understand the pathogenic role of B cells in Multiple Sclerosis (MS). Using the adoptive transfer system of experimental autoimmune encephalomyelitis (EAE), a murine model of MS, we have previously shown that mice in which B cells are the only MHCII-expressing antigen presenting cell (APC) are susceptible to EAE. However, a reproducible delay in the day of onset of disease driven by exclusive B cell antigen presentation suggests that B cells require optimal conditions to function as APCs in EAE. In this study, we utilize an <i>in vivo</i> genetic system to conditionally and temporally regulate expression of MHCII to test the hypothesis that B cell APCs mediate attenuated and delayed neuroinflammatory T cell responses during EAE. Remarkably, induction of MHCII on B cells following the transfer of encephalitogenic CD4 T cells induced a rapid and robust form of EAE, while no change in the time to disease onset occurred for recipient mice in which MHCII is induced on a normal complement of APC subsets. Changes in CD4 T cell activation over time did not account for more rapid onset of EAE symptoms in this new B cell-mediated EAE model. Our system represents a novel model to study how the timing of pathogenic cognate interactions between lymphocytes facilitates the development of autoimmune attacks within the CNS.</p></div