Determination of longitudinal and lateral directional aerodynamic characteristics of the B19B pressure-fed booster and the B19B booster/040A orbiter launch configuration

The 0.003366 scale models of the space shuttle pressure-fed booster and booster/orbiter configurations were tested in the MSFC 14-inch trisonic wind tunnel. The test was conducted as a static stability and control investigation over a Mach range of 0.60 to 5.00. The booster alone configuration was tested with various tail sizes, tail wedge angles, tail flaps, spoilers, and a body flare drag skirt. Two launch configurations were tested; one being the MSC orbiter location on the booster tank and the other being the North American Rockwell orbiter location. Orbiter buildup, longitudinal position, incidence angle, and booster tail on and off were the variables for launch configuration. Booster alone models were pitched over an angle of attack range of -4 to +14 and +20 to +60 deg at zero deg yaw angle and yawed over an angle of sideslip range of -10 to +10 deg at 52 deg angle of attack. Launch configuration models were yawed -10 to +10 deg at zero degrees angle of attack and yawed -10 to +10 deg at zero and -6 deg angle of attack. All models were rolled 45 deg during selected runs

Space shuttle: Verification of booster transition characteristics for transonic and supersonic Mach numbers (M equals 0.6 - 5.0)

The results of the booster verification wind tunnel test are presented. These tests were conducted in a 14 x 14-inch trisonic wind tunnel utilizing a .0035 scale model. The nominal Mach numbers tested were 0.6, 0.9, 0.95, 1.0, 1.05, 1.20, 1.50, 2.0, 2.74, 3.00, 4.50 and 5.0. The angle of attack range was +5 to 40 deg. The yaw data was obtained over a range of -10 to +10 deg at fixed angles of attack of 0, 6, 15, 25, and 30 deg. The Reynolds number range was 4.2 to 6.9 million per foot. Results include elevon and canard effectiveness in pitch, and rudder, aileron, body flap, and tail effectiveness in yaw

Sugar beets in Minnesota

12 pages; includes photographs. This archival publication may not reflect current scientific knowledge or recommendations. Current information available from the University of Minnesota Extension: https://www.extension.umn.edu

INSTABILITY STUDIES WITH EBR-I, MARK III

The results of instability studies suggest that the operational characteristics of the fully ribbed and rigid Mark III loading are governed by feedback processes that guarantee safe and stable operation under normal operating condiiions. No evidence of positive reactivity effects was noted for the fully-ribbed rigid core. Logical extrapolations of full-power full-flow test data indicate that the reactor could be brought into a resonant condition for power levels exceeding 1000 Mw. Strong nonlinearities were observed in power coefficients and were considered to pose no serious operational problems above 200 kw in the power range associated with the tests. An application of the Nyquist stability criterion to the extrapolated fully sheared data results in the conclusion that the reactor would attain resonance instability at full flow at - 11 Mw. Logical extrapolations of test data for one-third flow results in resonance instability at -10 Mw, a power level -20 times that designed for onethird flow. Rib shearing was shown to result in an unexpected and unexplained increase in the magnitude of the delayed structural power coefficient component. An empirical fit of feedback data to a model describing the dynamic and static behavior of the partially sheared core resulted in ihe values for the respective prompt negative, rod-bowing, and delayed structural power coefficient components of -2.21 x 10/sup -6/ +0.543 x 10/sup -6/ and -0.873 x 10/sup -6/4 delta /k/kw. The over all behavior of the Mark III core, whether fully ribbed and rigid, fully ribbed and loose, or even partially or fully sheared, is one of extreme stability. The inclusion of stabilizing ribs and a system of tightening rods in the Mark lII design elimuinated, or at least reduced to a point beyond detection, the prompt positive rod-bowing component that existed in the Mark II. (B.O.G.

The phantom midge menace: Migratory Chaoborus larvae maintain poor ecosystem state in eutrophic inland waters

Chaoborus spp. (phantom midge) are prevalent in eutrophic lakes with methane-rich, oxygen depleted hypolimnion and sediments, and the methane-poor, oxygen-rich epilimnion. Using a combination of experiments and system modelling, we demonstrated that the larvae’s burrowing activities in and out of the sediment perturbed the sediment and reintroduced sequestered phosphorus into the overlying water, thereby exacerbating internal nutrient loading in the water column. Fluxes of sediment methane and other reduced solutes enhanced by the larval bioturbation sustain the hypoxic/anoxic condition below the thermocline. Migrating larvae also directly transported methane in their gas vesicles from the deep water and release it in the surface water, potentially contributing to methane emission to air. As nutrient pollution and climate warming persist or worsen in the coming decades, proliferation of Chaoborus could intensify this positive feedback loop and delay lake recovery

Precision measurements of the total and partial widths of the psi(2S) charmonium meson with a new complementary-scan technique in antiproton-proton annihilations

We present new precision measurements of the psi(2S) total and partial widths from excitation curves obtained in antiproton-proton annihilations by Fermilab experiment E835 at the Antiproton Accumulator in the year 2000. A new technique of complementary scans was developed to study narrow resonances with stochastically cooled antiproton beams. The technique relies on precise revolution-frequency and orbit-length measurements, while making the analysis of the excitation curve almost independent of machine lattice parameters. We study the psi(2S) meson through the processes pbar p -> e+ e- and pbar p -> J/psi + X -> e+ e- + X. We measure the width to be Gamma = 290 +- 25(sta) +- 4(sys) keV and the combination of partial widths Gamma_e+e- * Gamma_pbarp / Gamma = 579 +- 38(sta) +- 36(sys) meV, which represent the most precise measurements to date.Comment: 17 pages, 3 figures, 3 tables. Final manuscript accepted for publication in Phys. Lett. B. Parts of the text slightly expanded or rearranged; results are unchange

CSI 2264: Probing the inner disks of AA Tauri-like systems in NGC 2264

Context. The classical T Tauri star (CTTS) AA Tau has presented photometric variability that was attributed to an inner disk warp, caused by the interaction between the inner disk and an inclined magnetosphere. Previous studies of the young cluster NGC 2264 have shown that similar photometric behavior is common among CTTS. Aims. The goal of this work is to investigate the main causes of the observed photometric variability of CTTS in NGC 2264 that present AA Tau-like light curves, and verify if an inner disk warp could be responsible for their observed variability. Methods. In order to understand the mechanism causing these stars’ photometric behavior, we investigate veiling variability in their spectra and u − r color variations and estimate parameters of the inner disk warp using an occultation model proposed for AA Tau. We also compare infrared Spitzer IRAC and optical CoRoT light curves to analyze the dust responsible for the occultations. Results. AA Tau-like variability proved to be transient on a timescale of a few years. We ascribe this variability to stable accretion regimes and aperiodic variability to unstable accretion regimes and show that a transition, and even coexistence, between the two is common. We find evidence of hot spots associated with occultations, indicating that the occulting structures could be located at the base of accretion columns. We find average values of warp maximum height of 0.23 times its radial location, consistent with AA Tau, with variations of on average 11% between rotation cycles. We also show that extinction laws in the inner disk indicate the presence of grains larger than interstellar grains. Conclusions. The inner disk warp scenario is consistent with observations for all but one star with AA Tau-like variability in our sample. AA Tau-like systems are fairly common, comprising 14% of CTTS observed in NGC 2264, though this number increases to 35% among systems of mass 0.7 M_⊙ ≲ M ≲ 2.0 M_⊙. Assuming random inclinations, we estimate that nearly all systems in this mass range likely possess an inner disk warp. We attribute this to a possible change in magnetic field configurations among stars of lower mass

Characteristics of Family Lives in Central Europe

In this chapter, authors give a picture of families in individual countries, which participated in the survey, so from the Czech Republic, Slovakia, Germany, Poland, Ukraine and Latvia. They pay attentionmainly to the family changes after the year 1990. There is mainly demographic situation. Furthermore, there are features which present contemporary family such as an increase of democratization in family coexistence in connection with the shifts of roles and disintegration in a family life linked with overall individualism manifested by automation, where one creates his/her own way of life. The contemporary family is more likely affected in all countries by progressive social differentiation; in a different level of unemployment, certain isolation and changes are always seen in intergeneration relationships. The authors also pay attention to family social policy and housing situation when starting a family

Nonlinear Network Dynamics on Earthquake Fault Systems

Earthquake faults occur in networks that have dynamical modes not displayed by single isolated faults. Using simulations of the network of strike-slip faults in southern California, we find that the physics depends critically on both the interactions among the faults, which are determined by the geometry of the fault network, as well as on the stress dissipation properties of the nonlinear frictional physics, similar to the dynamics of integrate-and-fire neural networks.Comment: 12 pages, 4 figure

Genomic structure and alterations of homeobox gene CDX2 in colorectal carcinomas

Expression of CDX2, a caudal-related homeobox gene, was found to be decreased in colorectal carcinomas. Heterozygous null mutant mice as to Cdx2 develop multiple intestinal adenomatous polyps. To clarify the role of CDX2 in colorectal carcinogenesis, we determined its genomic structure, and searched for mutations of CDX2 in 49 sporadic colorectal carcinomas and ten hereditary non-polyposis colorectal cancers (HNPCC) without microsatellite instability. None of them exhibited a mutation. We further examined 19 HNPCC carcinomas with microsatellite instability for mutations in a (G)7 repeat site within CDX2. One of them (5.3%) exhibited one G insertion. Loss of heterozygosity was observed in 2 of the 20 (10%) informative sporadic carcinomas, and in one of the three (33.3%) informative HNPCC cancers. These data indicate that CDX2 may play only a minor role in colorectal carcinogenesis. © 1999 Cancer Research Campaig