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Organic light-emitting diodes (OLEDs) fabricated on flexible plastic substrates are the focus of increasing attention due to their broad potential applications in portable devices such as cellular phones, personal digital assistants (PDAs), and laptops, etc., which require light weight and mechanical durability. [1,2] Heeger and co-workers first reported flexible OLEDs, fabricated from a conducting polymer electrode deposited on poly(ethylene terephthalate) (PET).[3] It was generally thought at the time that mechanical flexibility could only be achieved with a polymeric electrode. However, Forrest and co-workers subsequently demonstrated flexible, vacuum-deposited, small-molecule OLEDs fabricated on indium tin oxide (ITO)-coated PET and having the structure PET/ITO/ TPD/Alq/MgAg/AgÐanalogous to those of conventional glass-based devices, and capable of repeated flexing.[4] Subsequently, small-molecule OLEDs have been fabricated on several kinds of plastic or plastic/inorganic hybrid substrates, pre-coated with a transparent conductive oxide (TCO) such as ITO, by conventional pulsed-laser deposition or sputtering. [2,5,6] TCO growth on plastic remains a significant challenge for the fabrication of truly efficient flexible OLEDs, due to the poor thermal and mechanical properties of typical polymeric substrates. This is illustrated in ITO film growth on glass, where relatively high deposition and/or post-annealing temperatures (>200 C) are typically required to achieve reasonable electrical conductivity, optical transparency, and longterm stability. Conventionally, ITO film growth on plastic has been achieved by low-temperature deposition techniques such as sputtering. However, such films are typically amorphous, leading to poor conductivity, transparency, and adhesion properties, and underscoring the need for an improved growth technique. In contrast to simple sputtering, ion-assisted deposition (IAD) is uniquely suited for producing smooth, adherent, and microstructurally dense thin oxide films at remarkably low temperatures.[7] IAD employs two ion beams to effect simultaneous film deposition, oxidation, and crystallization, resulting in smooth, dense, coherent films at low temperatures. In addition, the assisting ion bombardment generates fresh surfaces during the pre-and in-situ cleaning/activation process, creating strong interfacial adhesion and removal of voids that can trap loosely bound/physisorbed O 2 , which may degrade OLED performance. These attractions raise the interesting question of whether IAD could be effectively employed in low-temperature ITO depositions for OLEDs, especially on plastics, because ITO's physical properties, such as work function, conductivity, morphology, and surface composition, etc., which significantly influence OLED performance, are strongly dependent on the specific deposition process and post-treatment. [8] To date, there have been no reports of OLED fabrication with IAD-deposited ITO. [9] We report here the growth and characteristics of high-quality ITO thin films on bo...

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In archaeology, we are accustomed to investing great effort into collecting data from fieldwork, museum collections, and other sources, followed by detailed description, rigorous analysis, and in many cases ending with publication of our findings in short, highly concentrated reports or journal articles. Very often, these publications are all that is visible of this lengthy process, and even then, most of our journal articles are only accessible to scholars at institutions paying subscription fees to the journal publishers. While this traditional model of the archaeological research process has long been effective at generating new knowledge about our past, it is increasingly at odds with current norms of practice in other sciences. Often described as ‘open science’, these new norms include data stewardship instead of data ownership, transparency in the analysis process instead of secrecy, and public involvement instead of exclusion. While the concept of open science is not new in archaeology (e.g., see Lake 2012 and other papers in that volume), a less transparent model often prevails, unfortunately. We believe that there is much to be gained, both for individual researchers and for the discipline, from broader application of open science practices. In this article, we very briefly describe these practices and their benefits to researchers. We introduce the Society of American Archaeology’s Open Science Interest Group (OSIG) as a community to help archaeologists engage in and benefit from open science practices, and describe how it will facilitate the adoption of open science in archaeology.

Neutral models are foundational in the archaeological study of cultural transmission. Applications have assumed that archaeological data represent synchronic samples, despite the accretional nature of the archaeological record. Using numerical simulations, I document the circumstances under which time-averaging alters the distribution of model predictions. Richness is inflated in long-duration assemblages, and evenness is "flattened" compared to unaveraged samples. Tests of neutrality, employed to differentiate between biased and unbiased models, suffer serious problems with Type I error under time-averaging. Estimation of populationlevel innovation rates, which feature in many archaeological applications, are biased even without time averaging, but have sharply increased bias given longer assemblage durations. Finally, the time scale over which time averaging alters predictions is determined by the mean trait lifetime, providing a way to evaluate the impact of these effects upon archaeological samples.