259 research outputs found
Uniform Laws or State Immunity? The Constitutionality of Section 106(a) After Seminole, 39 J. Marshall L. Rev. 969 (2006)
Bonding of reusable surface insulation with low density silicone foams
The development and evaluation of a reduced density, high reliable foamed bond strain isolation system for attaching reusable surface insulation to the space shuttle structure are reported. Included are data on virgin materials as well as on materials that received 100 cycles of exposure to 650 F for approximately 20 minutes per cycle. Room temperature vulcanizing silicon elastomers meet all the requirments for an adhesive bonding system
Leadership and Trust in Partially Distributed Software Development Teams
Partially distributed teams (PDTs) are common as organizations collaborate across distances. A PDT has at least one collocated subteam and at least two geographically dispersed subteams. We describe a large-scale experiment that examines student global PDTs working on software requirements for an emergency MIS; the teams comprised one U.S. subteam and one Dutch subteam. Leadership configuration was varied so that some teams had only a team leader; some had only subteam leaders; and some had both. However most teams chose to select subteam leaders, regardless of instructions. Trust has been found to be important for team functioning in traditional and virtual teams. This paper focuses on the experimental results related to leadership and trust in PDTs. Results indicate that while there is no evidence that trust varies by leadership configuration, the type of leader (subteam/team) matters and that trust is associated with leader effectiveness and perceptions of team and subteam performance
Nanopatterning Gold by Templated Solid State Dewetting on the Silica Warp and Weft of Diatoms
The diatom, Nitzschia palea, exhibits complex silica shell (frustule) topography that resembles the warp and weft pattern of woven glass. The surface is perforated with a rhombic lattice of roughly oblong pores between periodically undulating transverse weft costae. Exfoliated frustules can be used to template gold nanoparticles by thermally induced dewetting of thin gold films. Acting as templates for the process, the frustules give rise to two coexisting hierarchies of particle sizes and patterned distributions of nanoparticles. By examining temperature dependent dewetting of 5, 10, and 15 nm Au films for various annealing times, we establish conditions for particle formation and patterning. The 5 nm film gives distributions of small particles randomly distributed over the surface and multiple particles at the rhombic lattice points in the pores. Thicker films yield larger faceted particles on the surface and particles that exhibit shapes that are roughly conformal with the shape of the pore container. The pores and costae are sources of curvature instabilities in the film that lead to mass transport of gold and selective accumulation in the weft valleys and pores. We suggest that, with respect to dewetting, the frustule comprises 2-dimensional sublattices of trapping sites. The pattern of dewetting is radically altered by interposing a self-assembled molecular adhesive of mercaptopropyltrimethoxysilane between the Au film overlayer and the frustule. By adjusting the interfacial energy in this manner, a fractal-like overlay of Au islands coexists with a periodic distribution of nanoparticles in the pores
Online teacher development: collaborating in a virtual learning environment
Over recent years educational institutions have been making increasing use of virtual environments to set up collaborative activities for learners. While it is recognized that teachers play an important role in facilitating learner collaboration online they may not have the necessary skills to do so successfully. Thus, a small scale professional development programme was set up and piloted by two distance universities. The aims were to develop teachers’ experience of online group work; to trial a set of pilot activities which would raise awareness of factors contributing to successful collaborative online activity; and to identify professional development needs in this area. This article reports on the hands-on experience of a group of 20 teachers, examines some of the competences that are needed to successfully collaborate in virtual environments, and presents the skills that teachers need to foster online collaborative learning in the virtual classroom. Quantitative and qualitative data were collected, examining the levels of participation among participants, the collaborative activity of two groups, and teacher perception of the collaboration which took place. The skills identified include planning and managing the collaboration, designing appropriate activities, giving clear instructions and getting students to negotiate ground rules for participation, moderating at the right level, and choosing the right environment and the appropriate tool(s). While this study was carried out with language teachers, many of the findings are applicable to other subject areas where growing emphasis is placed on the development of collaborative skills
Online collaboration and cooperation : the recurring importance of evidence, rationale and viability
This paper investigates collaboration in teaching and learning and draws out implications for the promotion of collaboration within online environments. It is divided into four sections. First the case for collaboration, including specifically cooperative approaches, is explored. This case revolves around the impact of collaboration on the quality of learning and on learning outcomes. Collaboration is seen as constrained by context but, if structured and rewarded, it will bring important motivational and cognitive benefits. Next, the case for online collaboration is examined. This is based on longstanding arguments about the benefits of working together albeit in an environment which offers greater reach; a mix of media; and archives of interaction. The third section of the paper compares perspectives on online collaboration with a longer tradition of research into collaboration in general; it critiques the idea that online mediation offers a paradigm change in teaching and learning. The fourth section of the paper considers future directions for promoting online collaboration
Group Support Systems: experiments with an online system and implications for same-time/different places working
This is the author accepted manuscript. The final version is available from Springer via the DOI in this recordWe present an analysis of the Group Explorer Group Support System (GSS) from the perspective of its implementation as technology that can support same-time/different-places group workshops. The purpose of the chapter is to report on our experiences with using a same-time/different places GSS, introduce issues that arise from these experiences, and discuss future prospects. The chapter commences by reviewing our current understanding of GSS and how they support the use of distributed Problem Structuring Methods (PSMs) in both single organization and multi-organization settings. The configuration and use of a cloud-based online version of the GSS is presented that highlights some of the key technological, organisational and facilitation issues involved in supporting distributed PSM workshops. The future development of such online GSS is discussed with a particular focus on two emerging research questions; the future role of the facilitator in online GSS, and the commonalities between online GSS and social media platforms as different-times/different-places group working, such as crowdsourcing, become prevalent in the context of increasing globalisation and the ongoing decentralisation of work environments.Engineering and Physical Sciences Research Council (EPSRC)Natural Environment Research Council (NERC)European Union FP7European Union Horizon 202
Rich pictures : Researching the role of peer interaction for pupils using the Internet
Electronic information resources, including the Internet, provide young people with opportunities to interact with each other and with vast quantities of information. Research has indicated that learning and cognitive development are intricately linked to opportunities to process and interact with relevant information and the medium used to deliver this information may well have an impact on these opportunities. This research aimed to inform policymaking and contribute to locally situated, and global, knowledge. In order to achieve these aims a constructivist approach, focusing on sixteen, in-depth, holistic case studies was used to produce ‘rich pictures’. These rich pictures revealed a variety of ways in which access to the Internet can provide valuable learning opportunities in relation to cognitive, affective and social variables. Peer interaction in the electronic environment plays a significant part in contributing to cognitive development, this paper concentrates on that interaction and discusses ways in which it can impact positively on learning opportunities for young people
Advancing Research for the Management of Long-Lived Species: A Case Study on the Greenland Shark
Long-lived species share life history traits such as slow growth, late maturity, and low fecundity, which lead to slow recovery rates and increase a population’s vulnerability to disturbance. The Greenland shark (Somniosus microcephalus) has recently been recognized as the world’s longest-lived vertebrate, but many questions regarding its biology, physiology, and ecology remain unanswered. Here we review how current and future research will fill knowledge gaps about the Greenland shark and provide an overall framework to guide research and management priorities for this species. Key advances include the potential for specialized aging techniques and demographic studies to shed light on the distribution and age-class structure of Greenland shark populations. Advances in population genetics and genomics will reveal key factors contributing to the Greenland shark’s extreme longevity, range and population size, and susceptibility to environmental change. New tagging technologies and improvements in experimental and analytical design will allow detailed monitoring of movement behaviors and interactions among Greenland sharks and other marine species, while shedding light on habitat use and susceptibility to fisheries interactions. Interdisciplinary approaches, such as the combined use of stable isotope analysis and high-tech data-logging devices (i.e., accelerometers and acoustic hydrophones) have the potential to improve knowledge of feeding strategies, predatory capabilities, and the trophic role of Greenland sharks. Measures of physiology, including estimation of metabolic rate, as well as heart rate and function, will advance our understanding of the causes and consequences of long lifespans. Determining the extent and effects of current threats (as well as potential mitigation measures) will assist the development of policies, recommendations, and actions relevant for the management of this potentially vulnerable species. Through an interdisciplinary lens, we propose innovative approaches to direct the future study of Greenland sharks and promote the consideration of longevity as an important factor in research on aquatic and terrestrial predators
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