The pursuit of isotopic and molecular fire tracers in the polar atmosphere and cryosphere

We present an overview of recent multidisciplinary, multi-institutional efforts to identify and date major sources of combustion aerosol in the current and paleoatmospheres. The work was stimulated, in part, by an atmospheric particle \u27sample of opportunity\u27 collected at Summit, Greenland in August 1994, that bore the 14C imprint of biomass burning. During the summer field seasons of 1995 and 1996, we collected air filter, surface snow and snowpit samples to investigate chemical and isotopic evidence of combustion particles that had been transported from distant fires. Among the chemical tracers employed for source identification are organic acids, potassium and ammonium ions, and elemental and organic components of carbonaceous particles. Ion chromatography, performed by members of the Climate Change Research Center (University of New Hampshire), has been especially valuable in indicating periods at Summit that were likely to have been affected by the long range transport of biomass burning aerosol. Univariate and multivariate patterns of the ion concentrations in the snow and ice pinpointed surface and snowpit samples for the direct analysis of particulate (soot) carbon and carbon isotopes. The research at NIST is focusing on graphitic and polycyclic aromatic carbon, which serve as almost certain indicators of fire, and measurements of carbon isotopes, especially 14C, to distinguish fossil and biomass combustion sources. Complementing the chemical and isotopic record, are direct \u27visual\u27 (satellite imagery) records and less direct backtrajectory records, to indicate geographic source regions and transport paths. In this paper we illustrate the unique way in which the synthesis of the chemical, isotopic, satellite and trajectory data enhances our ability to develop the recent history of the formation and transport of soot deposited in the polar snow and ice

Hachimoji DNA and RNA: A genetic system with eight building blocks

Reported here are DNA and RNA-like systems built from eight (hachi-) nucleotide letters (-moji) that form four orthogonal pairs. This synthetic genetic biopolymer meets the structural requirements needed to support Darwinism, including a polyelectrolyte backbone, predictable thermodynamic stability, and stereoregular building blocks that fit a Schrödinger aperiodic crystal. Measured thermodynamic parameters predict the stability of hachimoji duplexes, allowing hachimoji DNA to double the information density of natural terran DNA. Three crystal structures show that the synthetic building blocks do not perturb the aperiodic crystal seen in the DNA double helix. Hachimoji DNA was then transcribed to give hachimoji RNA in the form of a functioning fluorescent hachimoji aptamer. These results expand the scope of molecular structures that might support life, including life throughout the cosmos

Lignin biomarkers as tracers of mercury sources in lakes water column

This study presents the role of specific terrigenous organic compounds as important vectors of mercury (Hg) transported from watersheds to lakes of the Canadian boreal forest. In order to differentiate the autochthonous from the allochthonous organic matter (OM), lignin derived biomarker signatures [Lambda, S/V, C/V, P/(V ? S), 3,5-Bd/V and (Ad/Al)v] were used. Since lignin is exclusively produced by terrigenous plants, this approach can give a non equivocal picture of the watershed inputs to the lakes. Moreover, it allows a characterization of the source of OM and its state of degradation. The water column of six lakes from the Canadian Shield was sampled monthly between June and September 2005. Lake total dissolved Hg concentrations and Lambda were positively correlated, meaning that Hg and ligneous inputs are linked (dissolved OM r2 = 0.62, p\0.0001; particulate OM r2 = 0.76, p\0.0001). Ratios of P/(V ? S) and 3,5-Bd/V from both dissolved OM and particulate OM of the water column suggest an inverse relationship between the progressive state of pedogenesis and maturation of the OM in soil before entering the lake, and the Hg concentrations in the water column. No relation was found between Hg levels in the lakes and the watershed flora composition—angiosperm versus gymnosperm or woody versus non-woody compounds. This study has significant implications for watershed management of ecosystems since limiting fresh terrestrial OM inputs should reduce Hg inputs to the aquatic systems. This is particularly the case for largescale land-use impacts, such as deforestation, agriculture and urbanization, associated to large quantities of soil OM being transferred to aquatic systems

Does inequality erode generalized trust? Evidence from Romanian youths

Generalized trust is a critical component of liberal democratic citizenship. We evaluate the extent to which exposure to socioeconomic inequality erodes trust among Romanian youths. Using national survey data of Romanian eighth-grade and high school students, we evaluate this effect as a product of socioeconomic diversity within the classroom, controlling for the social status of the students as well as socioeconomic inequality within the community where the school is located. Our analysis shows that generalized trust is higher for students in higher grades. However, despite this maturing effect, students exposed to greater levels of socioeconomic diversity have significantly lower levels of trust. The effect is particularly acute for students in the ninth grade. This finding holds when controlling for socioeconomic diversity and polarization in the community. The result reinforces the idea that generalized trust develops early in one’s life and is quite stable, although a major life transformation, such as entering high school, may alter trust depending on the social context

Immune Responses to Plague Infection in Wild Rattus rattus, in Madagascar: A Role in Foci Persistence?

Plague is endemic within the central highlands of Madagascar, where its main reservoir is the black rat, Rattus rattus. Typically this species is considered susceptible to plague, rapidly dying after infection inducing the spread of infected fleas and, therefore, dissemination of the disease to humans. However, persistence of transmission foci in the same area from year to year, supposes mechanisms of maintenance among which rat immune responses could play a major role. Immunity against plague and subsequent rat survival could play an important role in the stabilization of the foci. In this study, we aimed to investigate serological responses to plague in wild black rats from endemic areas of Madagascar. In addition, we evaluate the use of a recently developed rapid serological diagnostic test to investigate the immune response of potential reservoir hosts in plague foci.We experimentally infected wild rats with Yersinia pestis to investigate short and long-term antibody responses. Anti-F1 IgM and IgG were detected to evaluate this antibody response. High levels of anti-F1 IgM and IgG were found in rats one and three weeks respectively after challenge, with responses greatly differing between villages. Plateau in anti-F1 IgM and IgG responses were reached for as few as 500 and 1500 colony forming units (cfu) inoculated respectively. More than 10% of rats were able to maintain anti-F1 responses for more than one year. This anti-F1 response was conveniently followed using dipsticks.Inoculation of very few bacteria is sufficient to induce high immune response in wild rats, allowing their survival after infection. A great heterogeneity of rat immune responses was found within and between villages which could heavily impact on plague epidemiology. In addition, results indicate that, in the field, anti-F1 dipsticks are efficient to investigate plague outbreaks several months after transmission

Embedding cultural competence in faculty : a mixed-methods evaluation of an applied Indigenous proficiency workshop

One of the most pressing issues in Australian society is the gap between Indigenous and non-Indigenous health and life expectancies (Marmot, 2017). Australia agreed with the World Health Organisation’s 2008 Closing the Gap in a Generation report (WHO, 2008), spending approximately 5.6% of government expenditure towards ameliorating this gap (Gardiner-Garden & Simon-Davies, 2012), yet there have been only minimal positive outcomes (Alford, 2015; Gannon, 2018). In applied terms, this means Indigenous people are still dying younger (Anderson et al., 2016), scoring higher on psychological distress (Markwick, Ansari, Sullivan, & McNeil, 2015) and suffering poorer indices on all chronic diseases (e.g. Walsh & Kangaharan, 2016; Thompson, Talley, & Kong, 2017). The level of complexity involved in addressing these “wicked” or seemingly “impossible to solve” health problems is made worse by the lack of any pan-national strategic planning and/or intervention evaluation (Lokuge et al., 2017), even though there has been a plethora of programs and projects designed to improve Indigenous health (see for example, AGPC, 2016). Leaders in health and educational institutions must consider why there is a lack of progress in closing the gap in Indigenous health and life expectancies. Addressing the inequities in Indigenous health requires a determinant of health approach (Mitrou et al., 2014), as 39% of the gap in health outcomes can be explained by social determinates (AIHW, 2017; Markwick, Ansari, Sullivan, Parsons, & McNeil, 2014). The social determinant considered to most reliably predict Indigenous poor health is racism (Kelaher, Ferdinand, & Paradies, 2014; Paradies, 2006; Paradies & Cunningham, 2009; Paradies et al., 2015; Paradies, Truong, & Priest, 2014)

Flexible mapping of homology onto structure with Homolmapper

<p>Abstract</p> <p>Background</p> <p>Over the past decade, a number of tools have emerged for the examination of homology relationships among protein sequences in a structural context. Most recent software implementations for such analysis are tied to specific molecular viewing programs, which can be problematic for collaborations involving multiple viewing environments. Incorporation into larger packages also adds complications for users interested in adding their own scoring schemes or in analyzing proteins incorporating unusual amino acid residues such as selenocysteine.</p> <p>Results</p> <p>We describe homolmapper, a command-line application for mapping information from a multiple protein sequence alignment onto a protein structure for analysis in the viewing software of the user's choice. Homolmapper is small (under 250 K for the application itself) and is written in Python to ensure portability. It is released for non-commercial use under a modified University of California BSD license. Homolmapper permits facile import of additional scoring schemes and can incorporate arbitrary additional amino acids to allow handling of residues such as selenocysteine or pyrrolysine. Homolmapper also provides tools for defining and analyzing subfamilies relative to a larger alignment, for mutual information analysis, and for rapidly visualizing the locations of mutations and multi-residue motifs.</p> <p>Conclusion</p> <p>Homolmapper is a useful tool for analysis of homology relationships among proteins in a structural context. There is also extensive, example-driven documentation available. More information about homolmapper is available at <url>http://www.mcb.ucdavis.edu/faculty-labs/lagarias/homolmapper_home/homolmapper%20web%20page.htm</url>.</p

Evolving the theory and praxis of knowledge translation through social interaction: a social phenomenological study

Background: As an inherently human process fraught with subjectivity, dynamic interaction, and change, social interaction knowledge translation (KT) invites implementation scientists to explore what might be learned from adopting the academic tradition of social constructivism and an interpretive research approach. This paper presents phenomenological investigation of the second cycle of a participatory action KT intervention in the home care sector to answer the question: What is the nature of the process of implementing KT through social interaction? Methods: Social phenomenology was selected to capture how the social processes of the KT intervention were experienced, with the aim of representing these as typical socially-constituted patterns. Participants (n = 203), including service providers, case managers, administrators, and researchers organized into nine geographically-determined multi-disciplinary action groups, purposefully selected and audiotaped three meetings per group to capture their enactment of the KT process at early, middle, and end-of-cycle timeframes. Data, comprised of 36 hours of transcribed audiotapes augmented by researchers\u27 field notes, were analyzed using social phenomenology strategies and authenticated through member checking and peer review. Results: Four patterns of social interaction representing organization, team, and individual interests were identified: overcoming barriers and optimizing facilitators; integrating \u27science push\u27 and \u27demand pull\u27 approaches within the social interaction process; synthesizing the research evidence with tacit professional craft and experiential knowledge; and integrating knowledge creation, transfer, and uptake throughout everyday work. Achieved through relational transformative leadership constituted simultaneously by both structure and agency, in keeping with social phenomenology analysis approaches, these four patterns are represented holistically in a typical construction, specifically, a participatory action KT (PAKT) model. Conclusion: Study findings suggest the relevance of principles and foci from the field of process evaluation related to intervention implementation, further illuminating KT as a structuration process facilitated by evolving transformative leadership in an active and integrated context. The model provides guidance for proactively constructing a \u27fit\u27 between content, context, and facilitation in the translation of evidence informing professional craft knowledge

Stable Carbon and Nitrogen Isotopes in a Peat Profile Are Influenced by Early Stage Diagenesis and Changes in Atmospheric CO2 and N Deposition

In this study, we test whether the δ13C and δ15N in a peat profile are, respectively, linked to the recent dilution of atmospheric δ13CO2 caused by increased fossil fuel combustion and changes in atmospheric δ15N deposition. We analysed bulk peat and Sphagnum fuscum branch C and N concentrations and bulk peat, S. fuscum branch and Andromeda polifolia leaf δ13C and δ15N from a 30-cm hummock-like peat profile from an Aapa mire in northern Finland. Statistically significant correlations were found between the dilution of atmospheric δ13CO2 and bulk peat δ13C, as well as between historically increasing wet N deposition and bulk peat δ15N. However, these correlations may be affected by early stage kinetic fractionation during decomposition and possibly other processes. We conclude that bulk peat stable carbon and nitrogen isotope ratios may reflect the dilution of atmospheric δ13CO2 and the changes in δ15N deposition, but probably also reflect the effects of early stage kinetic fractionation during diagenesis. This needs to be taken into account when interpreting palaeodata. There is a need for further studies of δ15N profiles in sufficiently old dated cores from sites with different rates of decomposition: These would facilitate more reliable separation of depositional δ15N from patterns caused by other processes