Helping the Transition Through Building New Friendships: A Psychological Perspective on Supporting International Students\u27 Acculturation and Social Integration

In the present research, I developed a program that paired newcomer international students with Canadian student mentors. These pairs met weekly throughout the year. Analysis of pilot quantitative data suggested international student participants did not experience changes in attitudes towards Canadian students or feelings of integration at university as they got to know their mentors, contrary to what I had initially hypothesized. After conducting focus group interviews and reforming the survey measures for the main study, I found that program participants experienced positive changes in sociocultural and psychological adaptation, and a reduction in acculturative stress over time. At the conclusion of the program, program participants also showed higher levels of psychological adaptation and lower levels of acculturative stress than control participants, who had not participated in the program. These findings make an important contribution to the empirical literature on the acculturation of international students and provide foundations for future research

Evolution of the Electron Yield Curves of Insulators as a Function of Impinging Electron Fluence and Energy

Electron emission and concomitant charge accumulation near the surface of insulators is central to understanding spacecraft charging. A study of changes in electron emission yields as a result of internal charge buildup due to electron dose is presented. Evolution of total, backscattered, and secondary yield results over a broad range of incident energies are presented for two representative insulators, Kapton and Al2O3. Reliable yield curves for uncharged insulators are measured, and quantifiable changes in yields are observed due to \u3c100-fC/mm2 fluences. Excellent agreement with a phenomenological argument based on insulator charging predicted by the yield curve is found; this includes a decrease in the rate of change of the yield as incident energies approach the crossover energies and as accumulated internal charge reduces the landing energy to asymptotically approach a steady state surface charge and unity yield. It is also found that the exponential decay of yield curves with fluence exhibit an energy-dependent decay constant alpha(E). Finally, physics-based models for this energy dependence are discussed. Understanding fluence and energy dependence of these charging processes requires knowledge of how charge is deposited within the insulator, the mechanisms for charge trapping and transport within the insulator, and how the profile of trapped charge affects the transport and emission of charges from insulator

Non-Intrusive Sensor for In-Situ Measurement of Recession Rate of Ablative and Eroding Materials

A non-intrusive sensor for in-situ measurement of recession rate of heat shield ablatives. An ultrasonic wave source is carried in the housing. A microphone is also carried in the housing, for collecting the reflected ultrasonic waves from an interface surface of the ablative material. A time phasing control circuit is also included for time-phasing the ultrasonic wave source so that the waves reflected from the interface surface of the ablative material focus on the microphone, to maximize the acoustic pressure detected by the microphone and to mitigate acoustic velocity variation effects through the material through a de-coupling process that involves a software algorithm. A software circuit for computing the location off of which the ultrasonic waves scattered to focus back at the microphone is also included, so that the recession rate of the heat shield ablative may be monitored in real-time through the scan-focus approach

Low-fluence Electron Yields of Highly Insulating Materials

Electron-induced electron yields of high-resistivity high-yield materials - ceramic polycrystalline aluminum oxide and polymer polyimide (Kapton HN) - were made by using a low-fluence pulsed incident electron beam and charge neutralization electron source to minimize charge accumulation. Large changes in the energy-dependent total yield curves and yield decay curves were observed, even for incident electron fluences of \u3c 3 fC/mm2. The evolution of the electron yield as charge accumulates in the material is modeled in terms of electron recapture based on an extended Chung-Everhart model of the electron emission spectrum. This model is used to explain the anomalies measured in highly insulating high-yield materials and to provide a method for determining the limiting yield spectra of uncharged dielectrics. The relevance of these results to spacecraft charging is also discussed

Helping the Transition: Mentorship to Support International Students in Canada

We developed a program that paired newcomer international students with Canadian student mentors. These pairs met weekly throughout a semester and international student participants completed measures at both the beginning and end of the program. We found that program participants experienced positive changes in sociocultural and psychological adaptation, and a reduction in acculturative stress over time. At the conclusion of the program, program participants also showed higher levels of psychological adaptation and lower levels of acculturative stress than control participants, who had not participated in the program. These findings make an important contribution to the empirical literature on the acculturation of international students and provide foundations for future research

Current status and future directions of precision aerial application for site-specific crop management in the USA

The first variable-rate aerial application system was developed about a decade ago in the USA and since then, aerial application has benefitted from these technologies. Many areas of the United States rely on readily available agricultural airplanes or helicopters for pest management, and variable-rate aerial application provides a solution for applying field inputs such as cotton growth regulators, defoliants, and insecticides. In the context of aerial application, variable-rate control can simply mean terminating spray over field areas that do not require inputs, terminating spray near pre-defined buffer areas determined by Global Positioning, or applying multiple rates to meet the variable needs of the crop. Prescription maps for aerial application are developed using remote sensing, Global Positioning, and Geographic Information System technologies. Precision agriculture technology has the potential to benefit the agricultural aviation industry by saving operators and farmers time and money

Development and prospect of unmanned aerial vehicle technologies for agricultural production management

Unmanned aerial vehicles have been developed and applied to support agricultural production management. Compared with piloted aircraft, an Unmanned Aerial Vehicle (UAV) can focus on small crop fields at lower flight altitudes than regular aircraft to perform site-specific farm management with higher precision. They can also “fill in the gap” in locations where fixed winged or rotary winged aircraft are not readily available. In agriculture, UAVs have primarily been developed and used for remote sensing and application of crop production and protection materials. Application of fertilizers and chemicals is frequently needed at specific times and locations for site-specific management. Routine monitoring of crop plant health is often required at very high resolution for accurate site-specific management as well. This paper presents an overview of research involving the development of UAV technology for agricultural production management. Technologies, systems and methods are examined and studied. The limitations of current UAVs for agricultural production management are discussed, as well as future needs and suggestions for development and application of the UAV technologies in agricultural production management

The Conductor-Dielectric Junctions in a Low Density Plasma

A conductor-dielectric junction exposed to the space environment is a frequent spacecraft design feature. Due to spacecraft charging and/or solar array operation, the conductor can acquire a high potential with respect to the surrounding plasma. If this potential is positive the insulators adjacent to exposed conductors can collect current as if they were conductors themselves. This phenomenon, called snapover, results in a substantial increase in current collection, and may even result in a glow discharge if the potential is high enough. If a conductor has a negative potential, arcing can occur at the site of a junction. Both of these phenomena negatively affect spacecraft operation. To prevent negative consequences, the physical mechanisms of snapover and arc inception require investigation. In this paper, results are presented of an experimental and theoretical study of snapover, glow discharge, and arc phenomena for different materials immersed in argon or xenon plasmas. The effect of snapover is investigated for several metal-dielectric junctions: copper-teflon, copper-Kapton, copper-glass, aluminum-teflon, aluminum-Kapton, steelteflon, anodized aluminum with pinholes, and copper-ceramics. I-V curves are measured and snapover inception voltages, essential parameters (increase in current and collection area due to secondary electrons), and glow discharge inception thresholds are determined. Optical spectra are obtained for glow discharges in both argon and xenon plasmas. These spectra provide information regarding atomic species entrapped in the glow region. Some spectral lines can be used to estimate plasma parameters in the discharge area. A videocamera and linear array were used to confirm that snapover inception is accompanied by very low intensity visible light emission. This result seems to be important for the estimate of the light pollution around spacecraft. Optical spectra (wavelengths 380-650 nm) of arcs are also obtained on a negatively biased chromic acid anodized aluminum plate immersed in low density argon and xenon plasmas. Analysis of these spectra confirms our earlier findings that aluminum atoms are ejected from the arc site. Moreover, it is found that chromium atoms are also quite abundant in the arc plasma. It is believed that the latter results contribute considerably to the understanding of processes of plasma contamination caused by arcing

More than 50% of players sustained a time-loss injury (>1 day of lost training or playing time) during the 2012 Super Rugby Union Tournament : a prospective cohort study of 17 340 player-hours

BACKGROUND : Professional rugby union is a contact sport with a high risk of injury. OBJECTIVE : To document the incidence and nature of time-loss injuries during the 2012 Super Rugby tournament. DESIGN : Prospective cohort study SETTING : 2012 Super Rugby tournament (Australia, New Zealand, South Africa) PARTICIPANTS : 152 players from 5 South African teams METHODS : Team physicians collected daily injury data through a secure, web-based electronic platform. Data included size of the squad, type of day, main player position, training or match injury, hours of play (training and matches), time of the match injury, mechanism of injury, main anatomical location of the injury, specific anatomical structure of the injury, the type of injury, the severity of the injury (days lost). RESULTS : The proportion (%) of players sustaining a time-loss injury during the tournament (IPP) was 55%, and 25% of all players sustained >1 injury. The overall incidence rate (IR per 1000 player-hours) of injuries was 9.2. The IR for matches (83.3) was significantly higher than for training (2.1) and the IR was similar for forwards and backs. Muscle/tendon (50%) and joint/ligament (32.7%) injuries accounted for >80% of injuries. Most injuries occurred in the lower (48.1%) and upper limb (25.6%). 42% of all injuries were moderate (27.5%) or severe (14.8%), and tackling (26.3%) and being tackled (23.1%) were the commonest mechanisms of injury. The IR of injuries was unrelated to playing at home compared with away (locations > 6 hours time difference). CONCLUSION : 55% of all players were injured during the 4-month Super Rugby tournament (1.67 injuries / match). Most injuries occurred in the lower (knee, thigh) or upper limb (shoulder, clavicle). 42% of injuries were severe enough for players to not play for > 1 week.Clinical Sport and Exercise Medicine Research Fund (partial funding) International Olympic Committee (IOC) Research Center (Cape Town) (partial funding) South African Rugby Football Union (partial funding)http://bjsm.bmj.com/hb201