Kinetic Monte Carlo simulations of oscillatory shape evolution for electromigration-driven islands

The shape evolution of two-dimensional islands under electromigration-driven periphery diffusion is studied by kinetic Monte Carlo (KMC) simulations and continuum theory. The energetics of the KMC model is adapted to the Cu(100) surface, and the continuum model is matched to the KMC model by a suitably parametrized choice of the orientation-dependent step stiffness and step atom mobility. At 700 K shape oscillations predicted by continuum theory are quantitatively verified by the KMC simulations, while at 500 K qualitative differences between the two modeling approaches are found.Comment: 7 pages, 6 figure

Assessment feedback to enhance student development as effective construction industry practitioners

Assessment feedback has been identified as playing a key role in enhancing student learning and academic success, and effective feedback can also promote selfregulating learners which in turn translates to more effective practitioners. There is a considerable amount of literature concerning assessment feedback, however most of the research is generic and does not focus on the needs of particular academic disciplines, nor of relevant professional practice. For built environment students, assessment feedback can strengthen links between academic learning and professional practice, supporting the development of effective construction industry practitioners. To evaluate assessment feedback within this context, a study focusing on links between assessment feedback and professional practice is being undertaken. Early findings are presented here, based on content analysis of assessment feedback on submitted assignments. Data was analysed using a numeric approach, recording frequency of key words. Findings suggest there is scope to enhance practice via the use of revised documents and thus enhance the student learning experience as well as promoting deep learning and development of reflective practitioners. This preliminary study indicates the need to re-consider wording of key documents provided to students

Male Reading Teachers: Effects on Inner-city Boys

Eighteen inner-city first and second grade boys participated in a pilot study on the effect of sex of reading teacher on boys’ attitudes toward and performance in reading. Each boy participated with either a male or a female research assistant in a 22-week Paired Reading intervention using texts shown to be of high interest to boys. Findings suggest that these contexts yield significant increases in boys’ reading performance, sense of physiological well-being while reading, and their sense of reading progress regardless of the sex of their reading teacher

Analysis of an ecotourist based management strategy: Crystal Cave, Yanchep National Park, Western Australia

Ecotourism has quickly become one of the most influential and prominent terms used within the tourism industry today. With its many obscure definitions ecotourism has also been used to support a great number of unsustainable tourist developments. This study examined whether ecotourism had the ability to ensure ecological and financial sustainability through increased public exposure and appreciation to an ecologically sensitive area. One place in which this notion is being put to the test is in Crystal Cave, a popular tourist destination inside Yanchep National Park, 50 kilometres north of Perth. This cave is named after the beautiful reflections off the groundwater pool within the Cave. However, tourist numbers have dropped in recent years due to the diminished aesthetical appeal of this cave as a result of the lowering of the groundwater pool. More importantly still has been the discovery of a new amphipod life form living within the groundwater pool of Crystal Cave. An intense effort is now being made by government agencies to save the species by artificially rejuvenating the pool within the Cave until its original levels can be restored through water conservation measures. Instead of excluding tourists from this environmentally sensitive area during the project, an ecotourist based model has been developed to increase tourist numbers, and therefore revenue, in order to subsidise a majority of the project. If properly managed, this ecotourist based management model has the ability to provide and exceptional example of an ecologically and financially sustainable project payed for by increased public exposure to an environmentally sensitive area

Geo-Ethics: What to do When Approval Authority Decisions Contradict Sound Science?

Three case studies in Canada are evaluated where a regulatory authority ruled that measures considered by some professionals to be without scientific basis and less protective of human health or the environment were the required courses of action. The three projects were in the field of environmental geoscience. In all three cases, the solution proposed by a Professional Geoscientist (P.Geo.) was opposed by a representative of a regulatory body that held authority for approval. The final outcomes that were approved by the regulator were less protective of human health (increased exposure to potential contaminants) and/or the environment (more resources used; higher contaminant exposure). In two of the three cases, the solutions were also more expensive to the client and the taxpayer.   This paper explores the practice of professionalism in geoscience versus regulatory authorities that hold jurisdiction over geoscience in a broad sense. In each of the three cases, the professional opinions and analysis of the P.Geo. working for a private sector client were overridden by a professional (P.Geo. or Professional Engineer) in an approval authority. These three studies highlight the ethical decisions required by professional geoscientists in the face of regulators who hold control over areas of geoscience. Although the training of professionals is similar, regulators appear to be influenced by perceived risk as opposed to actual risk based on scientific evidence. Similarly, some policies do not have a solid scientific basis. As a result, sound scientific reasoning and resulting rational decisions may be hindered in regulatory decision-making.RÉSUMÉTrois études de cas canadiens sont évaluées, où une autorité règlementaire a statué comme requises des mesures qui avaient été déclarées par des professionnels comme étant sans fondements scientifiques et moins protectrices pour la santé humaine ou les milieux de vie. Il s’agit de trois projets du domaine des géosciences des milieux de vie. Dans les trois cas, la solution proposée par un géologue professionnel (P.Geo.) a été contestée par un représentant d'un organisme règlementaire décisionnel. Les résultats définitifs approuvés par l'organisme règlementaire protégeait moins la santé humaine (augmentation de l'exposition aux contaminants potentiels) et/ou le milieu de vie (plus de ressources utilisées; augmentation de l'exposition aux contaminants). Dans deux des trois cas, les solutions étaient également plus coûteuses pour le client et le contribuable.   Le présent article explore la pratique professionnelle en géosciences par rapport à celle des autorités règlementaires qui ont juridiction dans le domaine des géosciences en général. Dans chacun de ces trois cas, les avis professionnels et l'analyse de P.Geo. travaillant pour un client du secteur privé ont été supplantés par celui d’un professionnel (P.Geo. ou ingénieur professionnel) œuvrant a sein d’une autorité règlementaire. Ces trois études mettent en lumière des décisions éthiques attendues de géoscientifiques professionnels face à des autorités règlementaires décisionnelles en certains domaines géoscientifiques. La formation de ces professionnels est similaire, mais il semble que les régulateurs soient influencés par le risque perçu plutôt que par le risque réel établi scientifiquement. De même, certaines politiques n'ont pas une base scientifique solide. Il s’en suit qu’un raisonnement scientifique solide et des décisions rationnelles qui en résultent peuvent être contrecarrés par une décision règlementaire

The species composition of Antarctic phytoplankton interpreted in terms of Tilman's competition theory

An attempt was made, to test for the impact of resource competition on Antarctic marine phytoplankton. According to theory, species composition near competitive equilibrium should be determined by the ratios of limiting resources. Enrichment bioassays identified silicon and nitrogen as limiting nutrients for some of the most important phytoplankton species during early austral summer in the region near the Antarctic Peninsula. Together with the generally acknowledged limiting resource light, this gave three meaningful ratios of essential resources (Si:N, Si:light, N:light) and one ratio of substitutable resources (NO sub(3):NH sub(4)). Phytoplankton species assemblages were found to be well separated by the ratios of the essential resources and by mixing depth