Report of the Terrestrial Bodies Science Working Group. Volume 3: Venus

The science objectives of Pioneer Venus and future investigations of the planet are discussed. Concepts and payloads for proposed missions and the supporting research and technology required to obtain the desired measurements from space and Earth-based observations are examined, as well as mission priorities and schedules

Seasonality of Social Behaviour Among Immature Belugas (Delphinapterus leucas) in Managed Care

Belugas ( Delphinapterus leucas ) in managed care have been reported to show seasonal variation in socio-sexual behaviour, hormone levels and respiration rates; however, little is known about the social interactions of wild belugas when they are not in summer, near-shore congregations. To better understand if belugas show seasonal variation in social interactions, this study recorded the behaviour of 10 belugas (five females, five males, ranging from birth to 10 years of age) housed in managed care. Social interactions typically peaked in the summer months but persisted at very low levels during the rest of the year. Sea - sonal variation was most dramatic for socio-sexual behaviour but was generally mirrored in pattern by agonistic and affiliative interactions. Subjects closer to maturity displayed more seasonal variation than younger subjects, and males displayed more seasonal variation compared to females. The peak in social interactions found in this study aligns rather closely with wild belugas’ sum - mer, near-shore congregations, where belugas have increased opportunities for socializing. Although belugas in managed care do not experience a seasonal change in habitat, they do show seasonal changes in social behaviour, which are likely driven by seasonal fluctuations in hormone levels. It is therefore expected that wild beluga populations would show similar behavioural pat - terns if they were observed throughout the remainder of the year. This research has applications for belugas in managed care and may provide a framework for understanding the social behaviour of wild belugas

Report of the Terrestrial Bodies Science Working Group. Volume 7: The Galilean satellites

The formational and evolutionary history of natural satellites, their mineralogical composition and other phenomena of scientific interest are discussed. Key scientific questions about IO, Ganymede, Callisto, and Europa are posed and the measurements and instruments required for a Galilean satellite lander in the 1980's are described

Hermitian Young Operators

Starting from conventional Young operators we construct Hermitian operators which project orthogonally onto irreducible representations of the (special) unitary group.Comment: 15 page

HAMSTRING MUSCLE ACTIVATION DIFFERENCES BETWEEN GENDERS WHILE PERFORMING SINGLE LEG LANDINGS

Women are 2-10 times more likely to incur an ACL injury compared to males. Hamstring neuromuscular differences between genders may contribute to genu valgum, a posture that is unfavorable to ACL integrity. The intention of this study was to examine hamstring activation patterns between genders when executing single leg landings. Ten male and ten female recreationally active subjects performed three repetitions of a single leg drop landing onto each leg. Surface EMG data were obtained from the medial and lateral hamstrings. A 2X2X2 repeated measures ANOVA indicated there were no main effects for gender, side, or muscle on the dependent variables (p > 0.05). Results of this study suggest that males and females exhibit similar medial/lateral hamstring neuromuscular activation strategies when landing from a jump

EFFECT OF BILATERAL OR SINGLE LEG LANDING ON KNEE KINEMATICS

Non-contact anterior cruciate ligament (ACL) injury has been shown to be more common in women than men, occurring at a rate of 6-8 times that of men (Hughes et al. (2008). Causes for this discrepancy are unknown, but differences in knee landing angle have been suggested as a possibility. Kinematic variables have been shown to be a major predictor in peak anterior tibial shear force (Schultz et al., 2009). Hughes et al. (2008) found that women display greater valgus angles and range of motion than men in a two legged landing. While Elvin et al. (2007) reported that knee contact angle was correlated to ground reaction forces and segment axial accelerations. Thus while it appears that knee kinematics are an important factor determining the stress on the knee in bilateral drop landings, in many cases, individuals cannot land on both legs and instead are forced to landing on a single leg. However, there is information lacking comparing knee joint angle and acceleration when landing on one versus two legs and these variables affect soft tissue forces on the knee. The purpose of this study was to compare knee joint range of motion and angular acceleration of the right and left leg during bilateral and single leg landings for males and females

The stellar dynamics and mass of NGC 1316 using the radial velocities of planetary nebulae

We present a study of the kinematics of the outer regions of the early-type galaxy NGC 1316, based on radial velocity measurements of 43 planetary nebulae as well as deep integrated-light absorption line spectra. The smoothed velocity field of NGC 1316 indicates fast rotation at a distance of 16 kpc, possibly associated with an elongated feature orthogonal to the inner dust lanes. The mean square stellar velocity is approximately independent of radius, and the estimated total mass of the system is 2.6 x 10^11 M_sun within a radius of 16 kpc, implying an integrated mass-to-light ratio of M/L_B = 8.Comment: 39 pages, 14 figures, in press on The Astrophysical Journal n. 50

Characteristics of Tenure-Line Faculty in Leadership Preparation Programs: An Analysis of Academic Preparation and Administrative Experience

This study investigated the credentials of 755 tenure-line educational leadership faculty members, using data collected through an online questionnaire. Findings disclosed that research institutions were significantly more likely than doctoral or comprehensive institutions to hire faculty with a PhD from a research university and who identified research as their primary professional strength. A greater proportion of faculty in comprehensive universities had served as school administrators before entering academe than was the case for those at research universities. These findings have significant implications for the field, given that an increasing number of school leaders nationally are prepared at comprehensive institutions

Unraveling the Helix Nebula: Its Structure and Knots

Through HST imaging of the inner part of the main-ring of the Helix Nebula together with CTIO 4-m images of the fainter outer parts, we have an unprecedented-quality view of the nearest bright planetary nebula. These images have allowed determination that the main-ring of the nebula is composed of an inner-disk of about 499\arcsec diameter (0.52 pc) surrounded by an outer-ring (in reality a torus) of 742\arcsec diameter (0.77 pc) whose plane is highly inclined to the plane of the disk. This outer-ring is surrounded by an outermost-ring of 1500\arcsec (1.76 pc) diameter which is flattened on the side colliding with the ambient interstellar medium. The inner-disk has an extended distribution of low density gas along its rotational axis of symmetry and the disk is optically thick to ionizing radiation, as is the outer-ring. Published radial velocities of the knots provides support for the two-component structure of the main-ring of the nebula and to the idea that the knots found there are expanding along with the nebular material from which it recently originated. There is a change in the morphology of the knots as a function of the distance from the local ionization front. This supports a scenario in which the knots are formed in or near the ionization front and are then sculpted by the stellar radiation from the central star as the ionization front advances beyond them.Comment: 30 pages, 20 figures, many figures have reduce fidelity for astroph preprint. Note: URLs in preprint were change