Three-dimensional in situ observations of compressive damage mechanisms in syntactic foam using X-ray microcomputed tomography

Royal Society Grant number RG140680 Lloyd's Register Foundation (GB) Oil and Gas Academy of Scotland Open access via Springer Compact AgreementPeer reviewedPublisher PD

A meteorological overview of the ARCTAS 2008 mission

The <i>A</i>rctic <i>R</i>esearch of the <i>C</i>omposition of the <i>T</i>roposphere from <i>A</i>ircraft and <i>S</i>atellites (ARCTAS) mission was a multi-aircraft project whose major objective was to investigate the factors driving changes in the Arctic's atmospheric composition and climate. It was conducted during April and June–July 2008. The summer ARCTAS deployment was preceded by a week of flights over and around California to address state issues of air quality and climate forcing. This paper focuses on meteorological conditions during the ARCTAS Spring and Summer campaigns. We examine mission averaged large-scale flow patterns at the surface, 500 hPa, and 300 hPa and determine their departures from climatology. Results from runs of the <i>W</i>eather <i>R</i>esearch and <i>F</i>orecasting (WRF) model are used to describe meteorological conditions on individual days. Our WRF configuration included a nested grid approach that provided horizontal spacing as small as 5 km. Trajectories calculated from the WRF output are used to determine transport pathways to the Arctic, including their origins and the altitudes at which they reach 70° N. We also present backward trajectories from selected legs of individual ARCTAS flights. Finally, the FLEXPART Lagrangian particle dispersion model, with the high resolution WRF data as input, is used to determine the paths of anthropogenic and biomass burning-derived CO. Results show that there was frequent and widespread transport to the Arctic during both phases of ARCTAS and that the three ARCTAS aircraft sampled air having a multitude of origins, following a myriad of paths, and experiencing many types of meteorological conditions

HLA-Associated viral mutations are common in human immunodeficiency virus type 1 elite controllers

Elite controllers (EC) of human immunodeficiency virus type 1 (HTV-1) maintain viremia below the limit of detection without antiretroviral treatment. Virus-specific cytotoxic CD8+ T lymphocytes are believed to play a crucial role in viral containment, but the degree of immune imprinting and compensatory mutations in EC is unclear. We obtained plasma gag, pol, and nef sequences from HLA-diverse subjects and found that 30 to 40% of the predefined HLA-associated polymorphic sites show evidence of immune selection pressure in EC., compared to approximately 50% of the sites in chronic progressors. These data indicate ongoing viral replication and escape from cytotoxic T lymphocytes are present even in strictly controlled HTV-1 infection

The Scottish economy [July 1981]

The current economic situation is extremely depressed and recent events suggest that, without significant increases in economic activity, the political and social fabric of this country may be several strained. However, as argued in the UK section, the prospects for recovery are bleak and reliance on a purely financial strategy to restore growth is in itself inadequate. The source of real economic growth lies in the ability of labour, capital and enterprise to come together in a manner conducive to increased productivity over time. It is therefore worthwhile examining these factors of production to determine the effect of current policies upon them

Review of the quarter's economic trends [October 1981]

In the second quarter of 1981 the index of industrial production for the United Kingdom was 8% below its level for the corresponding period in 1980. This notwithstanding, there do appear to be signs that the bottom of the output trough may now have been reached. This brief section will seek to understand the latest UK and world economic data to determine current economic conditions and forecasts future trends

Thirty Years After Michael E. Porter: What Do We Know About Business Exit?

Although a business exit is an important corporate change initiative, the buyer’s side seems to be more appealing to management researchers than the seller’s because acquisitions imply growth, i.e., success. Yet from an optimistic viewpoint, business exit can effectively create value for the selling company. In this paper we attempt to bring the relevance of the seller’s side back into our consciousness by asking: What do we know about business exit? We start our exploration with Porter (1976), focusing on literature that investigates the antecedents of, barriers to, and outcomes of business exit. We also include studies from related fields such as finance and economics.1 Through this research we determine three clusters of findings: factors promoting business exit, exit barriers, and exit outcomes. Overall, it is the intention of this paper to highlight the importance of business exit for research and practice. Knowing what we know about business exits and their high financial value we should bear in mind that exit need not mean failure but a new beginning for a corporation

Quasi-probability representations of quantum theory with applications to quantum information science

This article comprises a review of both the quasi-probability representations of infinite-dimensional quantum theory (including the Wigner function) and the more recently defined quasi-probability representations of finite-dimensional quantum theory. We focus on both the characteristics and applications of these representations with an emphasis toward quantum information theory. We discuss the recently proposed unification of the set of possible quasi-probability representations via frame theory and then discuss the practical relevance of negativity in such representations as a criteria for quantumness.Comment: v3: typos fixed, references adde

Longitudinal community plasma HIV-1 RNA concentrations and incidence of HIV-1 among injecting drug users: prospective cohort study

Objective To examine the relation between plasma HIV-1 RNA concentrations in the community and HIV incidence among injecting drug users

MicroRNAs Are Involved in the Development of Morphine-Induced Analgesic Tolerance and Regulate Functionally Relevant Changes in Serpini1.

Long-term opioid treatment results in reduced therapeutic efficacy and in turn leads to an increase in the dose required to produce equivalent pain relief and alleviate break-through or insurmountable pain. Altered gene expression is a likely means for inducing long-term neuroadaptations responsible for tolerance. Studies conducted by our laboratory (Tapocik et al., 2009) revealed a network of gene expression changes occurring in canonical pathways involved in neuroplasticity, and uncovered miRNA processing as a potential mechanism. In particular, the mRNA coding the protein responsible for processing miRNAs, Dicer1, was positively correlated with the development of analgesic tolerance. The purpose of the present study was to test the hypothesis that miRNAs play a significant role in the development of analgesic tolerance as measured by thermal nociception. Dicer1 knockdown, miRNA profiling, bioinformatics, and confirmation of high value targets were used to test the proposition. Regionally targeted Dicer1 knockdown (via shRNA) had the anticipated consequence of eliminating the development of tolerance in C57BL/6J (B6) mice, thus supporting the involvement of miRNAs in the development of tolerance. MiRNA expression profiling identified a core set of chronic morphine-regulated miRNAs (miR\u27s 27a, 9, 483, 505, 146b, 202). Bioinformatics approaches were implemented to identify and prioritize their predicted target mRNAs. We focused our attention on miR27a and its predicted target serpin peptidase inhibitor clade I (Serpini1) mRNA, a transcript known to be intricately involved in dendritic spine density regulation in a manner consistent with chronic morphine\u27s consequences and previously found to be correlated with the development of analgesic tolerance. In vitro reporter assay confirmed the targeting of the Serpini1 3′-untranslated region by miR27a. Interestingly miR27a was found to positively regulateSerpini1 mRNA and protein levels in multiple neuronal cell lines. Lastly, Serpini1 knockout mice developed analgesic tolerance at a slower rate than wild-type mice thus confirming a role for the protein in analgesic tolerance. Overall, these results provide evidence to support a specific role for miR27a and Serpini1 in the behavioral response to chronic opioid administration (COA) and suggest that miRNA expression and mRNA targeting may underlie the neuroadaptations that mediate tolerance to the analgesic effects of morphine

Einstein, incompleteness, and the epistemic view of quantum states

Does the quantum state represent reality or our knowledge of reality? In making this distinction precise, we are led to a novel classification of hidden variable models of quantum theory. Indeed, representatives of each class can be found among existing constructions for two-dimensional Hilbert spaces. Our approach also provides a fruitful new perspective on arguments for the nonlocality and incompleteness of quantum theory. Specifically, we show that for models wherein the quantum state has the status of something real, the failure of locality can be established through an argument considerably more straightforward than Bell's theorem. The historical significance of this result becomes evident when one recognizes that the same reasoning is present in Einstein's preferred argument for incompleteness, which dates back to 1935. This fact suggests that Einstein was seeking not just any completion of quantum theory, but one wherein quantum states are solely representative of our knowledge. Our hypothesis is supported by an analysis of Einstein's attempts to clarify his views on quantum theory and the circumstance of his otherwise puzzling abandonment of an even simpler argument for incompleteness from 1927.Comment: 18 pages, 8 figures, 1 recipe for cupcakes; comments welcom