Relaxation of Surface Profiles by Evaporation Dynamics

We present simulations of the relaxation towards equilibrium of one dimensional steps and sinusoidal grooves imprinted on a surface below its roughening transition. We use a generalization of the hypercube stacking model of Forrest and Tang, that allows for temperature dependent next-nearest-neighbor interactions. For the step geometry the results at T=0 agree well with the t^(1/4) prediction of continuum theory for the spreading of the step. In the case of periodic profiles we modify the mobility for the tips of the profile and find the approximate solution of the resulting free boundary problem to be in reasonable agreement with the T=0 simulations.Comment: 6 pages, Revtex, 5 Postscript figures, to appear in PRB 15, October 199

Emerging vehicle safety technologies and their potential benefits: discussion of expert opinions

The aim of this study was to consult experts from Australia and overseas about their views on emerging technologies, the likely uptake of these technologies and their potential to reduce the number of crashes or crash severity. Interviews were conducted with a cross-section of vehicle and road safety experts. The topics discussed included the most promising technologies, implementation issues, time frame, limitations, and opinions on future technologies, 20 - 30 years from now. In total, 16 interviews were conducted, with nine Australian-based experts and seven international experts. The experts' responses are discussed in the context of research literature on the technologies. The experts suggested that the most important emerging vehicle safety technologies are primary safety systems that provide increasing levels of automation. Autonomous Emergency Braking (AEB) was consistently identified as having the most potential in the near future, and this was confirmed in the literature. Early introduction of vehicle safety systems that are effective at preventing injury crashes will result in significant and cumulative financial and societal savings. This paper provides a brief overview of the more promising vehicle safety technologies, a summary of the opinions of the experts interviewed and potential mechanisms for accelerating uptake of vehicle safety technologies.Daniel Searson, Giulio Ponte, T Paul Hutchinson, Robert Anderson and Mary Lydo

Fundamental studies of passivity and passivity breakdown

This report summarizes the findings of our fundamental research program on passivity and passivity breakdown. During the past three and one half years in this program (including the three year incrementally-funded grant prior to the present grant), we developed and experimentally tested various physical models for the growth and breakdown of passive films on metal surfaces. These models belong to a general class termed point defects models'' (PDMs), in which the growth and breakdown of passive films are described in terms of the movement of anion and cation vacancies

Simultaneous Isolation of Circulating Nucleic Acids and EV-Associated Protein Biomarkers From Unprocessed Plasma Using an AC Electrokinetics-Based Platform.

The power of personalized medicine is based on a deep understanding of cellular and molecular processes underlying disease pathogenesis. Accurately characterizing and analyzing connections between these processes is dependent on our ability to access multiple classes of biomarkers (DNA, RNA, and proteins)-ideally, in a minimally processed state. Here, we characterize a biomarker isolation platform that enables simultaneous isolation and on-chip detection of cell-free DNA (cfDNA), extracellular vesicle RNA (EV-RNA), and EV-associated proteins in unprocessed biological fluids using AC Electrokinetics (ACE). Human biofluid samples were flowed over the ACE microelectrode array (ACE chip) on the Verita platform while an electrical signal was applied, inducing a field that reversibly captured biomarkers onto the microelectrode array. Isolated cfDNA, EV-RNA, and EV-associated proteins were visualized directly on the chip using DNA and RNA specific dyes or antigen-specific, directly conjugated antibodies (CD63, TSG101, PD-L1, GPC-1), respectively. Isolated material was also eluted off the chip and analyzed downstream by multiple methods, including PCR, RT-PCR, next-generation sequencing (NGS), capillary electrophoresis, and nanoparticle size characterization. The detection workflow confirmed the capture of cfDNA, EV-RNA, and EV-associated proteins from human biofluids on the ACE chip. Tumor specific variants and the mRNAs of housekeeping gene PGK1 were detected in cfDNA and RNA isolated directly from chips in PCR, NGS, and RT-PCR assays, demonstrating that high-quality material can be isolated from donor samples using the isolation workflow. Detection of the luminal membrane protein TSG101 with antibodies depended on membrane permeabilization, consistent with the presence of vesicles on the chip. Protein, morphological, and size characterization revealed that these vesicles had the characteristics of EVs. The results demonstrated that unprocessed cfDNA, EV-RNA, and EV-associated proteins can be isolated and simultaneously fluorescently analyzed on the ACE chip. The compatibility with established downstream technologies may also allow the use of the platform as a sample preparation method for workflows that could benefit from access to unprocessed exosomal, genomic, and proteomic biomarkers

A global ocean atlas of eukaryotic genes

While our knowledge about the roles of microbes and viruses in the ocean has increased tremendously due to recent advances in genomics and metagenomics, research on marine microbial eukaryotes and zooplankton has benefited much less from these new technologies because of their larger genomes, their enormous diversity, and largely unexplored physiologies. Here, we use a metatranscriptomics approach to capture expressed genes in open ocean Tara Oceans stations across four organismal size fractions. The individual sequence reads cluster into 116 million unigenes representing the largest reference collection of eukaryotic transcripts from any single biome. The catalog is used to unveil functions expressed by eukaryotic marine plankton, and to assess their functional biogeography. Almost half of the sequences have no similarity with known proteins, and a great number belong to new gene families with a restricted distribution in the ocean. Overall, the resource provides the foundations for exploring the roles of marine eukaryotes in ocean ecology and biogeochemistry

Online social media — a vehicle for city branding in China: the case of Sponge City Program (SCP)

The shift of academic attention from city marketing to city branding heralds a new era of representation and signification of cities as brands. Conscious practices of nationwide program implementation could be used not only for improving urban resilience but for city brands promotion. In China, to cope with the frequent occurrence of urban water issues, a nationwide initiative called Sponge City Program (SCP) has been launched since 2013. Given the significant impact of online social media on brand image, various levels of the Chinese Governments have begun to use online social media for city program promotion. In particular, brand community formed by stakeholders on online social media can significantly influence the brand image by co-creating contents. In this paper, we first analyze the current application of online social media for city marketing in China based on the SCP implementation. Next, we propose a framework/typology to inform how Chinese’ social media could be used for effective city branding. Finally, we conclude by discussing the implications of online social media use in China

Finite-size effects in bismuth nanowires

Arrays of semimetallic Bi nanowires, fabricated by electrodeposition, exhibit strong finite-size effects in transport properties as the carrier mean-free path is limited by the wire dimensions. We have observed a resistivity enhancement, a very large positive magnetoresistance, and a resistance maximum that depends on the strength and orientation of the magnetic field and the nanowire diameter. These results demonstrate electrodeposited Bi nanowires as a new medium for studying the intricate physics in Bi nanostructures. © 1998 The American Physical Society