67 research outputs found

    Why Do Molecules Echo Atomic Periodicity?

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    Franck–Condon factors are investigated for sequences of free main-group diatomic molecules. Theory-based Condon loci (parabolas) and Morse-potential loci are plotted on Deslandres tables to verify if they, indeed, follow the largest Franck–Condon factors. Then, the inclination angles of the Condon loci are determined. Thus, entire band systems are quantified by one variable, the angle. For all available isoelectronic sequences, this angle increases from a central minimum toward magic-number molecular boundaries. The theory for the Condon locus gives the angle in terms of the ratio of the upperstate to the lower-state force constants. It is concluded that the periodicity is caused due to the fact that this ratio becomes larger as rare-gas molecules are approached, a trend that probably points to the extreme cases of the rare-gas molecules themselves. Thus, molecular periodicity echoes atomic periodicity in that data plots have extrema at molecules with magic-number atoms, yet it does not echo the details of atomic periodicity in series between those molecules

    Directed Attention and Stereotype Threat in Interracial Interactions.

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    This research combines stereotype threat theory and attention restoration theory in an attempt to develop an intervention for stereotype threat. Applying stereotype threat to interracial communication provides a framework for understanding how Whites may have a more difficult time communicating about a race-related topic than another topic. Attention restoration theory contributes a potential intervention through the possibility of increasing cognitive resources available to threatened individuals in both a traditional stereotype threat paradigm and in an interracial communication paradigm. Study 1 tested the hypothesis that Whites may experience stereotype threat in interracial communication when discussing a race-related topic, and that this stereotype threat diminishes both speaking ability and recall of a partner's statement. Results supported this hypothesis, with participants exhibiting a higher rate of speech disfluencies and recalling fewer details of the partner's statements when the topic was race-related. Study 2 tested the hypothesis that restoring capacity for directed attention improves performance for women taking a math test under stereotype threat. Results did not support this hypothesis; the intervention did not improve participants' performance under stereotype threat, although it did have a positive impact on performance for those who were not under stereotype threat and for whom math performance was important. Lastly, Study 3 tested the hypothesis that increasing capacity for directed attention improves communication for Whites discussing a race-related topic. Results did not support this hypothesis, as the directed attention manipulation did not appear to have any effect on communication performance. The topic manipulation replicated the recall effects demonstrated in Study 1 but not the speech disfluency effects. The role of regulatory strategies in determining the effectiveness of manipulating directed attention is also discussed.Ph.D.PsychologyUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/64628/1/travist_1.pd

    A feeling for what's best: landscape aesthetics and notions of appropriate residential architecture in Dartmoor National Park, England

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    In England's national parks, the design of new dwellings represents a significant and contested part of landscape planning, inseparable from park conservation ideologies and policies. Within public discourse, new housing proposals can be praised for enhancing the landscape or decried for destroying it, while the decisions of planning authorities legitimise or marginalise different points-of-view. Set in Dartmoor National Park, this paper explores the competing aesthetic interpretations of landscape and the rural as represented within the design and planning of two separate residential sites that were redeveloped between 1998 and 2008. Discourse analysis of interviews (with architects, planners and clients), policies, and written accounts (planning applications and associated correspondence) investigates the positions of various stakeholders in response to these housing projects and to their protected rural landscape settings. Results reveal how notions of landscape context and aesthetics vary across different stakeholder groups, with design quality, sympathetic scale and landscape enhancement proving to be key areas of contention. Differing interpretations of national park planning policy, the problematic nature of communicating and judging qualitative aspects of ‘contemporary’ architecture, and the ongoing emphasis on visual aspects of landscape aesthetics mean that incorporating new housing design within national park landscapes remains challenging

    Transarterial Chemoembolization of Metastatic Colorectal Carcinoma with Drug-Eluting Beads, Irinotecan (DEBIRI): Multi-Institutional Registry

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    The purpose of this study was to evaluate the patient tolerance and efficacy of delivering locoregional chemotherapy to metastatic colorectal (MC) hepatic metastases via hepatic trans-arterial approach using irinotecan loaded drug eluting beads. This open-label, multi-center, single arm study included 30 MC patients, who had failed first line therapy. Of the 57 total embolization sessions, 12 (21% of sessions) were associated with adverse reactions during or after the treatment. After a median followup of 9 months, response rates by modified RECIST were 75% at 3 months and 66% at 6 months. Hepatic trans-arterial therapy using Irinotecan loaded DC BeadTM was safe and effective in the treatment of MCC as demonstrated by a minimal complication rate and acceptable tumor response

    Identifying Criegee intermediates as potential oxidants in the troposphere

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    Abstract and poster presented at the AGU Fall meeting, San Francisco 2015.Criegee intermediates (CI) are formed during the ozonolysis of unsaturated compounds and have been intensively studied in the last few years due to their possible role as oxidants in the troposphere. Stabilised CI (SCI) are now known to react very rapidly, k(298 K) = 10-12 to 10-10 cm3 molecule-1 s-1, with a large number of trace gases (SO2, NO2, organic acids, water dimers). Still, it remains challenging to assess their effective oxidative capacity, as CI chemistry is complex, spans a large range of rate coefficients for different SCI conformers reacting with water dimers and trace gases, and in addition no reliable measurement technique able to detect ambient SCI concentrations is currently available. In this study, we examine the extensive dataset from the HUMPPA-COPEC 2010 and the HOPE 2012 field campaigns, aided by literature data, to estimate the abundance of SCI in the lower troposphere. The budget of SCI is analyzed using four different approaches: 1) based on an observed yet unexplained H2SO4 production; 2) from the measured concentrations of unsaturated volatile organic compounds (VOC); 3) from OH reactivity measurements; 4) from the unexplained production rate of OH. A SCI concentration range between 5 x 103 and 2 x 106 molecule cm-3 is calculated for the two environments. The central weighted estimate of the SCI concentration over the boreal forest of ~ 5 x 104 molecules cm-3 implies a significant impact on the conversion of SO2 into H2SO4. In addition, we present measurements obtained using our inlet pre-injector laser-induced fluorescence assay by gas expansion technique (IPI-LIF-FAGE) for the above-mentioned campaigns. A recent laboratory study performed with the same instrumental setup showed that the IPI-LIF-FAGE system is sensitive to the detection of the OH formed from unimolecular decomposition of SCI. Building on these measurements, the background OH (OHbg) measured during the two field campaigns is investigated in comparison with many other trace gases to assess if the observations in controlled conditions are transferable to ambient conditions

    Estimating the atmospheric concentration of Criegee intermediates and their possible interference in a FAGE-LIF instrument

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    We analysed the extensive dataset from the HUMPPA-COPEC 2010 and the HOPE 2012 field campaigns in the boreal forest and rural environments of Finland and Germany, respectively, and estimated the abundance of stabilised Criegee intermediates (SCIs) in the lower troposphere. Based on laboratory tests, we propose that the background OH signal observed in our IPI-LIF-FAGE instrument during the aforementioned campaigns is caused at least partially by SCIs. This hypothesis is based on observed correlations with temperature and with concentrations of unsaturated volatile organic compounds and ozone. Just like SCIs, the background OH concentration can be removed through the addition of sulfur dioxide. SCIs also add to the previously underestimated production rate of sulfuric acid. An average estimate of the SCI concentration of similar to 5.0 x 10(4) molecules cm(-3) (with an order of magnitude uncertainty) is calculated for the two environments. This implies a very low ambient concentration of SCIs, though, over the boreal forest, significant for the conversion of SO2 into H2SO4. The large uncertainties in these calculations, owing to the many unknowns in the chemistry of Criegee intermediates, emphasise the need to better understand these processes and their potential effect on the self-cleaning capacity of the atmosphere.Peer reviewe

    Identifying Criegee intermediates as potential oxidants in the troposphere

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    Discussion started 24/10/16We analysed the extensive dataset from the HUMPPA-COPEC 2010 and the HOPE 2012 field campaigns in the boreal forest and rural environments of Finland and Germany, respectively, and estimated the abundance of stabilised Criegee intermediates (SCI) in the lower troposphere. Based on laboratory tests, we propose that the background OH signal observed in our IPI-LIF-FAGE instrument during the afore-mentioned campaigns is caused at least partially by SCI. This hypothesis is based on observed correlations with temperature and with concentrations of unsaturated volatile organic compounds and ozone. The background OH concentration also complements the previously underestimated production rate of sulfuric acid and is consistent with its scavenging through the addition of sulphur dioxide. A central estimate of the SCI concentration of ~ 5 × 104 molecules cm−3 (with an order of magnitude uncertainty) is calculated for the two environments. This implies a very low ambient concentration of SCI, though, over the boreal forest, significant for the conversion of SO2 into H2SO4. The large uncertainties in these calculations, owing to the many unknowns in the chemistry of Criegee intermediates, emphasise the need to better understand these processes and their potential effect on the self-cleaning capacity of the atmosphere

    Finishing the euchromatic sequence of the human genome

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    The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

    Systematics and Prediction in Franck-Condon Factors

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