A Closer Look at Relational Aggression

This research examines relational aggression and its increasing prominence in our culture today, specifically with school-aged children. Relational aggression, behaviors that inflict harm through manipulating, damaging, or controlling of relationships, has been proven to be an issue, but it is not easily recognized. Research has found a majority of schools do not mention relational aggression in their bullying contracts. Rather, schools focus on physical aggression, which leads to uneducated students and adults on the issue examined. This research discusses the definition, affects, causes, and needed preventions of relational aggression. Studies found that many aspects of an individual’s life work together to create relationally aggressive tendencies. This research looks at those aspects closely in attempts to educate and implement prevention plans for school-aged children

Pre-Heated Isentropic Gas in Groups of Galaxies

We confirm that the standard assumption of isothermal, shock-heated gas in cluster potentials is unable to reproduce the observed X-ray luminosity- temperature relation of groups of galaxies. As an alternative, we construct a physically motivated model for the adiabatic collapse of pre-heated gas into an isothermal potential that improves upon the original work of Kaiser (1991). The luminosity and temperature of the gas is calculated, assuming an appropriate distribution of halo formation times and radiation due to both bremsstrahlung and recombination processes. This model successfully reproduces the slope and dispersion of the luminosity-temperature relation of galaxy groups. We also present calculations of the temperature and luminosity functions for galaxy groups under the prescription of this model. This model makes two strong predictions for haloes with total masses M<10^13 M_sun, which are not yet testable with current data: (1) the gas mass fraction will increase in direct proportion to the halo mass; (2) the gas temperature will be larger than the virial temperature of the mass. The second effect is strong enough that group masses determined from gas temperatures will be overestimated by about an order of magnitude if it is assumed that the gas temperature is the virial temperature. The entropy required to match observations can be obtained by heating the gas at the turnaround time, for example, to about 3 X 10^6 K at z=1, which is too high to be generated by a normal rate of supernova explosions. This model breaks down on the scale of low mass clusters, but this is an acceptable limitation, as we expect accretion shocks to contribute significantly to the entropy of the gas in such objects.Comment: Final, refereed version, accepted by MNRAS. One new figure and several clarifying statements have been added. Uses mn.a4.sty (hacked mn.sty). Also available from http://astrowww.phys.uvic.ca/~balogh/entropy.ps.g

Phonons in a Nanoparticle Mechanically Coupled to a Substrate

The discrete nature of the vibrational modes of an isolated nanometer-scale solid dramatically modifies its low-energy electron and phonon dynamics from that of a bulk crystal. However, nanocrystals are usually coupled--even if only weakly--to an environment consisting of other nanocrystals, a support matrix, or a solid substrate, and this environmental interaction will modify the vibrational properties at low frequencies. In this paper we investigate the modification of the vibrational modes of an insulating spherical nanoparticle caused by a weak {\it mechanical} coupling to a semi-infinite substrate. The phonons of the bulk substrate act as a bath of harmonic oscillators, and the coupling to this reservoir shifts and broadens the nanoparticle's modes. The vibrational density of states in the nanoparticle is obtained by solving the Dyson equation for the phonon propagator, and we show that environmental interaction is especially important at low frequencies. As a probe of the modified phonon spectrum, we consider nonradiative energy relaxation of a localized electronic impurity state in the nanoparticle, for which good agreement with experiment is found.Comment: 10 pages, Revte

Neutrinos from beta processes in a presupernova: probing the isotopic evolution of a massive star

We present a new calculation of the neutrino flux received at Earth from a massive star in the $\sim 24$ hours of evolution prior to its explosion as a supernova (presupernova). Using the stellar evolution code MESA, the neutrino emissivity in each flavor is calculated at many radial zones and time steps. In addition to thermal processes, neutrino production via beta processes is modeled in detail, using a network of 204 isotopes. We find that the total produced $\nu_{e}$ flux has a high energy spectrum tail, at $E \gtrsim 3 - 4$ MeV, which is mostly due to decay and electron capture on isotopes with $A = 50 - 60$. In a tentative window of observability of $E \gtrsim 0.5$ MeV and $t < 2$ hours pre-collapse, the contribution of beta processes to the $\nu_{e}$ flux is at the level of $\sim90\%$ . For a star at $D=1$ kpc distance, a 17 kt liquid scintillator detector would typically observe several tens of events from a presupernova, of which up to $\sim 30\%$ due to beta processes. These processes dominate the signal at a liquid argon detector, thus greatly enhancing its sensitivity to a presupernova.Comment: 14 pages, 5 figure

A review of attitudes towards sharing geotechnical data and the use of geospatial data portals in Hong Kong and the U.K.: lessons for Europe

Reusing existing subsurface data can greatly cut the time and financial costs of site investigations, and reduce uncertainty regarding ground conditions that can result in delays and overspend. In Hong Kong SAR it is common practice for consultancies to deposit records in the form of factual and interpretive reports, borehole logs and laboratory test data with the Geotechnical Engineering Office (GEO) who make this information openly available to access for future investigative works. In addition to these deposits, other datasets available at GEO include, amongst others, landslide records, aerial photographs and as-built records. These archives are the first source of information about development sites in Hong Kong and no investigation takes place without a thorough desk study. Increasingly these data are digital, and can be accessed through a GIS-based online portal. In the U.K. the British Geological Survey (BGS) acts as a custodian for geoscience data deposited by the public and private sectors on a voluntary basis, and encourages organisations to make their data publicly available through the BGS online data portals. The facility to deposit digital data via the BGS website has recently been launched and should increase uptake of data sharing in the U.K. as it becomes easier for users to batch upload records digitally. Issues regarding data ownership and confidentiality are being overcome by the establishment, in some cities, of knowledge exchange networks where members who sign up to view data are expected under the terms of membership to deposit data. This has received backing from local government in some areas. The U.K. may not have the density of existing data that Hong Kong has but as knowledge exchange gathers momentum the BGS datasets are expected to grow rapidly. In Europe there appears to be a reluctance to share data. However, escalating demand for land, greater redevelopment of brownfield sites and an ever-growing need to ensure future construction and infrastructure projects are sustainable and compliant with European environmental targets means reusing data may have a role to play in increased subsurface knowledge, the reduction of unforeseen ground conditions and ultimately saving money. Data in .ags format is particularly favourable due to its uniform nature. First-hand experience of the approach towards disseminating geospatial data in Hong Kong and the U.K. will be presented, examining the difference in attitudes regarding data sharing in the two territories, and highlighting how it benefits ground investigations and geohazard assessment with the hope that Europe can learn lessons for the future and change old habits. The different systems of data sharing used in Hong Kong and the U.K. will be discussed, and their strengths and weaknesses evaluated with the aim of fostering a methodology for sharing geoscience data within Europe that benefits from the combined successes of both approaches and builds upon existing expertise

Flight tests of a direct lift control system during approach and landing

Flight tests of modified aileron direct lift control system during approach and landing of F8-C aircraf