Flight-test nacelles

Design modifications for acoustically absorbing flight test nacelles of DC-8 turbofan engin

Do children use different forms of verbal rehearsal in serial picture recall tasks? A multi-method study

Use of verbal rehearsal is a key issue in memory development. However, we still lack detailed and triangulated information about the early development and the circumstances in which different forms of rehearsal are used. To further understand significant factors that affect children’s use of various forms of rehearsal, the present study involving 108 primary school children adopted a multi-method approach. It combined a carefully chosen word length effect method with a self-paced presentation time method to obtain behavioural indicators of verbal rehearsal. In addition, subsequent trial-by-trial self-reports were gathered. Word length effects in recall suggested that phonological recoding (converting images to names - a necessary precursor for rehearsal) took place, with evidence of more rehearsal among children with higher performance levels. According to self-paced presentation times, cumulative rehearsal was the dominant form of rehearsal only for children with higher spans on difficult trials. The combined results of self-paced times and word length effects in recall suggest that ‘naming’ as simple form of rehearsal was dominant for most children. Self-reports were in line with these conclusions. Additionally, children used a mixture of strategies with considerable intra-individual variability, yet strategy use was nevertheless linked to age as well as performance levels

Visual orbit for the low-mass binary Gliese 22 AC from speckle interferometry

Based on 14 data points obtained with near-infrared speckle interferometry and covering an almost entire revolution, we present a first visual orbit for the low-mass binary system Gliese 22 AC. The quality of the orbit is largely improved with respect to previous astrometric solutions. The dynamical system mass is 0.592 +- 0.065 solar masses, where the largest part of the error is due to the Hipparcos parallax. A comparison of this dynamical mass with mass-luminosity relations on the lower main sequence and theoretical evolutionary models for low-mass objects shows that both probably underestimate the masses of M dwarfs. A mass estimate for the companion Gliese 22 C indicates that this object is a very low-mass star with a mass close to the hydrogen burning mass limit.Comment: Accepted by Astronomy and Astrophysics, 6 pages, 2 figure

Investigation to determine the effects of long-term bed rest on G-tolerance and on psychomotor performance Final report

Prolonged bed rest effects on gravity tolerance and psychomotor performance of human

The Flow of South Carolina Harvested Seafood Products through South Carolina Markets

Marketing,

A Super-Earth Orbiting the Nearby Sun-like Star HD 1461

We present precision radial velocity data that reveal a Super-Earth mass planet and two probable additional planets orbiting the bright nearby G0V star HD 1461. Our 12.8 years of Keck HIRES precision radial velocities indicate the presence of a 7.4M_Earth planet on a 5.77-day orbit. The data also suggest, but cannot yet confirm, the presence of outer planets on low-eccentricity orbits with periods of 446.1 and 5017 days, and projected masses (M sin i) of 27.9 and 87.1M_Earth, respectively. Test integrations of systems consistent with the radial velocity data suggest that the configuration is dynamically stable. We present a 12.2-year time series of photometric observations of HD 1461, which comprise 799 individual measurements, and indicate that it has excellent long-term photometric stability. However, there are small amplitude variations with periods comparable to those of the suspected 2nd and 3rd signals in the radial velocities near 5000 and 446 days, thus casting some suspicion on those periodicities as Keplerian signals. If the 5.77-day companion has a Neptune-like composition, then its expected transit depth is of order ~0.5 millimags. The geometric a priori probability of transits is ~8%. Phase-folding of the ground-based photometry shows no indication that transits of the 5.77-day companion are occurring, but high-precision follow-up of HD 1461 during upcoming transit phase windows will be required to definitively rule out or confirm transits. This new system joins a growing list of solar-type stars in the immediate galactic neighborhood that are accompanied by at least one Neptune- (or lower) mass planets having orbital periods of 50 days or less.Comment: 33 pages, 7 figure

Revealing the Young Starburst in Haro 3 with Radio and Infrared Imaging

The Wolf-Rayet galaxy Haro 3 (Mrk 35, NGC 3353) was observed at the near-IR and radio wavelengths as part of ongoing program to study the earliest stages of starbursts. These observations confirm that the current episode of star formation is dominated by a single region (region A). While there are knots of recent (~10 Myr) star formation outside of region A, the sources of ionizing radiation as observed in both radio and Br-gamma observations are almost exclusively associated with region A. The derived ionizing flux implies a star formation rate of ~0.6 solar masses per year localized within a radius of ~0.1 kpc. A comparison with observations from HST indicates that one or more of the star clusters in region A are optically obscured. The star clusters in region A have ages at least as young as ~5 Myr, and possibly as young as ~0.1 Myr. The star cluster that appears to be the youngest also exhibits a near-IR excess in its colors, possibly indicating natal dust in very close proximity to the ionizing stars. The difference between optical- and radio-determined ionizing fluxes as well as the near-IR colors indicate an average extinction value of A_V ~2.5 in region A. The total stellar mass associated with the current starburst in region A is inferred from both the near-IR and radio observations to be ~10^6 solar masses. The other main stellar concentrations observed in the near-IR (Regions B1 and B2) are somewhat older than region A, with ages ~8-10 Myr, and the near-IR observations indicate they have stellar masses of ~8x10^4 and ~2x10^4 solar masses, respectively.Comment: 17 pages, 3 figures, to appear in AJ August 200

On the interactions of lipids and proteins in the red blood cell membrane

The effects of temperature and of the action of a purified phospholipase C enzyme preparation on human red blood cell membranes has been investigated by chemical analyses, circular dichroism, and proton magnetic resonance measurements. The results indicate that a substantial fraction of the phospholipids and the proteins of the membranes can change structure independently of one another, suggesting a mosaic pattern for the organization of the lipids and proteins in membranes

A comparative study of CO adsorption on flat, stepped and kinked Au surfaces using density functional theory

Our ab initio calculations of CO adsorption energies on low miller index (111), (100), stepped (211), and kinked (532) gold surfaces show a strong dependence on local coordination with a reduction in Au atom coordination leading to higher binding energies. We find trends in adsorption energies to be similar to those reported in experiments and calculations for other metal surfaces. The (532) surface provides insights into these trends because of the availability of a large number of kink sites which naturally have the lowest coordination (6). We also find that, for all surfaces, an increase in CO coverage triggers a decrease in the adsorption energy. Changes in the work-function upon CO adsorption, as well as the frequencies of the CO vibrational modes are calculated, and their coverage dependence is reported.Comment: 18 pages, 4 figure

Probing jet properties via two particle correlation method

The formulae for calculating jet fragmentation momentum, $$, and parton transverse momentum,$$, and conditional yield are discussed in two particle correlation framework. Additional corrections are derived to account for the limited detector acceptance and inefficiency, for cases when the event mixing technique is used. The validity of our approach is confirmed with Monte-carlo simulation.Comment: Proceeding for HotQuarks2004 conference. 11 pages, 8 figures, corrected for typo